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1

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. PMID:15258091

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

2004-01-01

2

Similarity Criteria for the Laboratory Simulation of Supernova Hydrodynamics  

Microsoft Academic Search

The conditions for validity and the limitations of experiments intended to simulate astrophysical hydrodynamics are discussed, with application to some ongoing experiments. For systems adequately described by the Euler equations, similarity criteria required for properly scaled experiments are identified. The conditions for the applicability of the Euler equations are formulated, based on the analysis of localization, heat conduction, viscosity, and

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

1999-01-01

3

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

2012-07-01

4

29 CFR 1620.18 - Jobs performed under similar working conditions.  

Code of Federal Regulations, 2011 CFR

...Jobs performed under similar working conditions. 1620.18 Section 1620...Jobs performed under similar working conditions. (a) In general. ...to be performed under similar working conditions. It should be noted...

2011-07-01

5

29 CFR 1620.18 - Jobs performed under similar working conditions.  

Code of Federal Regulations, 2010 CFR

...Jobs performed under similar working conditions. 1620.18 Section 1620...Jobs performed under similar working conditions. (a) In general. ...to be performed under similar working conditions. It should be noted...

2010-07-01

6

Laboratory modeling of hypersonic flight conditions  

NASA Astrophysics Data System (ADS)

One of the key issues for vehicles in hypersonic flight and during atmospheric reentry is radio blackout due to weakly-ionized air plasma formation. When a spacecraft enters Earth's atmosphere or a vehicle travels through the atmosphere at hypersonic velocities, a shock wave is formed in front of the vehicle. The shock wave converts much of the vehicle's kinetic energy into heat and as a result the air molecules are dissociated and ionized. This plasma layer prevents normal telemetry transmission. This work considers a new approach to model the conditions of hypersonic flight in laboratory environment. The approach utilizes hypersonic plasma jet created by vacuum arc that hits immovable object intended to model a hypersonic vehicle. Heating of the object by the arc causes immediate re-evaporation of the jet's metal ions being deposited on the object's surface. This mimics absence of attachment of the air molecules to the vehicle in hypersonic flight. The plasma parameters and object temperatures are measured using electrostatic Langmuir probes and thermocouples respectively. The results of these experiments can be also used as calibration tool for tuning and debugging of numerical codes intended to predict and mitigate the blackout problem.

Shashurin, Alexey; Kundrapu, Madhusudhan; Loverich, John; Beilis, Isak; Keidar, Michael

2012-10-01

7

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

NASA Astrophysics Data System (ADS)

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

Garcia, M. H.

2011-12-01

8

42 CFR 494.130 - Condition: Laboratory services.  

Code of Federal Regulations, 2010 CFR

...FOR COVERAGE FOR END-STAGE RENAL DISEASE FACILITIES Patient Care § 494.130 Condition: Laboratory services. The dialysis facility must provide, or make available, laboratory services (other than tissue pathology and histocompatibility) to meet...

2010-10-01

9

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

Code of Federal Regulations, 2010 CFR

9 ? Animals and Animal Products ? 2 ? 2010-01-01 ? 2010-01-01 ? false ? Specimens for laboratory examination and similar purposes. ? 327.19 ? Section 327.19 ? Animals and Animal Products ? FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ? AGENCY ORGANIZATION AND TERMINOLOGY;...

2010-01-01

10

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

11

42 CFR 494.130 - Condition: Laboratory services.  

Code of Federal Regulations, 2014 CFR

...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION CONDITIONS FOR COVERAGE FOR END-STAGE RENAL DISEASE FACILITIES Patient Care § 494.130 Condition: Laboratory services. The dialysis facility must...

2014-10-01

12

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

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing moderate complexity testing; testing personnel. 493.1421 Section 493.1421 Public... LABORATORY REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity...

2010-10-01

13

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. 493.1487 Section 493.1487 Public... LABORATORY REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing...

2010-10-01

14

Extension of laboratory-measured soil spectra to field conditions  

NASA Technical Reports Server (NTRS)

Spectral responses of two glaciated soils, Chalmers silty clay loam and Fincastle silt loam, formed under prairie grass and forest vegetation, respectively, were measured in the laboratory under controlled moisture equilibria using an Exotech Model 20C spectroradiometer to obtain spectral data in the laboratory under artificial illumination. The same spectroradiometer was used outdoors under solar illumination to obtain spectral response from dry and moistened field plots with and without corn residue cover, representing the two different soils. Results indicate that laboratory-measured spectra of moist soil are directly proportional to the spectral response of that same field-measured moist bare soil over the 0.52 micrometer to 1.75 micrometer wavelength range. The magnitudes of difference in spectral response between identically treated Chalmers and Fincastle soils are greatest in the 0.6 micrometers to 0.8 micrometer transition region between the visible and near infrared, regardless of field condition or laboratory preparation studied.

Stoner, E. R.; Baumgardner, M. F.; Weismiller, R. A.; Biehl, L. L.; Robinson, B. F.

1982-01-01

15

A quasi-solution approach to Blasius similarity equation with general boundary conditions  

E-print Network

A recently developed method \\cite{Costinetal}, \\cite{Dubrovin}, and \\cite{BlasiusCT} is used to find an analytic approximate solution with rigorous error bounds to the classical Blasius similarity equation with general boundary conditions. This provides detailed proofs for the results reported in \\cite{Kim}.

Tae Eun Kim

2014-04-08

16

Seal formation in arid soil under natural and laboratory conditions  

NASA Astrophysics Data System (ADS)

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

Sarah, Pariente; Sachs, Eyal

2013-04-01

17

Laboratory simulations of NAT formation approaching stratospheric conditions  

NASA Technical Reports Server (NTRS)

Previous laboratory studies have established the stability conditions of nitric acid trihydrate (NAT), of which type 1 polar stratospheric cloud (PSC 1) particles are thought to be composed. However, NAT samples in lab studies were almost always formed under conditions very different from those of the stratosphere. In order to better understand the in situ growth of PSC 1 particle populations, samples of water and nitric acid were deposited under conditions of temperature and pressure which more closely approximate the polar stratosphere. The compositions of the solids, measured shortly after deposition, depended on the H2O:HNO3 ratio in the vapor from which the solids were condensed. Solids formed from vapor mixtures that approached stratospheric contained significantly less HNO3 than the 25 mol percent expected of NAT.

Marti, James; Mauersberger, Konrad

1994-01-01

18

Effects of experimental housing conditions on recovery of laboratory mice.  

PubMed

The beneficial effects of environment and social support during disease recovery in humans are widely accepted. Because laboratory mice are social animals and are highly motivated to interact with each other and with their environment, it is very likely that environmental and social factors are also beneficial to their recovery from experimental interventions or spontaneous diseases. The beneficial effects of enriched environments have been particularly well analyzed in the field of brain disorders, but several studies suggest that positive social contact and a complex and familiar environment may also support recovery from injury, from invasive procedures such as surgery or from spontaneously occurring diseases. The author reviews relevant publications on the effects of environment and social housing on recovery from disease or surgery in laboratory mice and other rodents. She concludes that in addition to promoting animal welfare, provision of optimal experimental housing conditions might also contribute to the clinical relevance of preclinical animal models by more closely simulating the environmental and social characteristics of disease recovery in humans. PMID:25602397

Jirkof, Paulin

2015-01-20

19

Hind limb unloading, a model of spaceflight conditions, leads to decreased B lymphopoiesis similar to aging.  

PubMed

Within the bone marrow, the endosteal niche plays a crucial role in B-cell differentiation. Because spaceflight is associated with osteoporosis, we investigated whether changes in bone microstructure induced by a ground-based model of spaceflight, hind limb unloading (HU), could affect B lymphopoiesis. To this end, we analyzed both bone parameters and the frequency of early hematopoietic precursors and cells of the B lineage after 3, 6, 13, and 21 d of HU. We found that limb disuse leads to a decrease in both bone microstructure and the frequency of B-cell progenitors in the bone marrow. Although multipotent hematopoietic progenitors were not affected by HU, a decrease in B lymphopoiesis was observed as of the common lymphoid progenitor (CLP) stage with a major block at the progenitor B (pro-B) to precursor B (pre-B) cell transition (5- to 10-fold decrease). The modifications in B lymphopoiesis were similar to those observed in aged mice and, as with aging, decreased B-cell generation in HU mice was associated with reduced expression of B-cell transcription factors, early B-cell factor (EBF) and Pax5, and an alteration in STAT5-mediated IL-7 signaling. These findings demonstrate that mechanical unloading of hind limbs results in a decrease in early B-cell differentiation resembling age-related modifications in B lymphopoiesis.-Lescale, C., Schenten, V., Djeghloul, D., Bennabi, M., Gaignier, F., Vandamme, K., Strazielle, C., Kuzniak, I., Petite, H., Dosquet, C., Frippiat, J.-P., Goodhardt, M. Hind limb unloading, a model of spaceflight conditions, leads to decreased B lymphopoiesis similar to aging. PMID:25376832

Lescale, Chloé; Schenten, Véronique; Djeghloul, Dounia; Bennabi, Meriem; Gaignier, Fanny; Vandamme, Katleen; Strazielle, Catherine; Kuzniak, Isabelle; Petite, Hervé; Dosquet, Christine; Frippiat, Jean-Pol; Goodhardt, Michele

2014-11-01

20

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

PubMed

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

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

2012-06-01

21

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

ERIC Educational Resources Information Center

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

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

22

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

NASA Astrophysics Data System (ADS)

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

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

23

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

24

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

NASA Astrophysics Data System (ADS)

We derive the integrability conditions of nonautonomous nonlinear Schrödinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painlevé method. We show that while the Painlevé 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 Painlevé method are retrieved as a special case of our general integrability conditions. We also derive the integrability conditions of nonautonomous nonlinear Schrödinger equations for two- and three-spacial dimensions.

Al Khawaja, U.

2010-05-01

25

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

26

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

27

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

Code of Federal Regulations, 2010 CFR

...Reinstatement of laboratories performing nonwaived testing. 493.807 Section 493.807 Public...REQUIREMENTS Participation in Proficiency Testing for Laboratories Performing Nonwaived Testing § 493.807 Condition:...

2010-10-01

28

DO TIE LABORATORY BASED METHODS REALLY REFLECT FIELD CONDITIONS  

EPA Science Inventory

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

29

Aspects of bulk atmospheric boundary layer similarity under free-convective conditions  

Microsoft Academic Search

For many hydrologic and atmospheric dynamic purposes the turbulent surface fluxes of sensible and latent (or evaporative) energy and of momentum must be formulated over areas covering a wide range of spatial scales; these are characteristically the scales of river basins and of the grid sizes for integration in current atmospheric circulation models. The bulk atmospheric boundary layer (ABL) similarity

Wilfried Brutsaert

1999-01-01

30

Similarities between exercise-induced hypoalgesia and conditioned pain modulation in humans.  

PubMed

Pain inhibitory mechanisms are often assessed by paradigms of exercise-induced hypoalgesia (EIH) and conditioned pain modulation (CPM). In this study it was hypothesized that the spatial and temporal manifestations of EIH and CPM were comparable. The participants were 80 healthy subjects (40 females), between 18 and 65 years of age in this randomized, repeated-measures cross-over trial that involved data collection on 2 different days. CPM was assessed by 2 different cold pressor tests (hand and foot). EIH was assessed by 2 intensities of aerobic bicycling exercises and 2 intensities of isometric muscle contraction exercises (arm and leg). Pressure pain thresholds (PPTs) were recorded before, during, after, and 15 minutes after conditioning/exercise at sites local to and remote from the extremity used for cold pressor stimulation and exercise. PPTs increased at local as well as at remote sites during both cold pressor tests and after all of the exercise conditions except low-intensity bicycling. EIH after bicycling was higher in women than in men. CPM and the EIH responses after isometric exercises were comparable in men and women and were not affected by age. The EIH response was larger in the exercising body part compared with nonexercising body parts for all exercise conditions. High-intensity exercise produced greater EIH responses than did low-intensity exercise. The change in PPTs during cold pressor tests and the change in PPTs after exercises were not correlated. The CPM response was not dominated by local manifestations, and the effect was seen only during the stimulation, whereas exercise had larger local manifestations, and the effects were also found after exercise. PMID:24076045

Vaegter, Henrik Bjarke; Handberg, Gitte; Graven-Nielsen, Thomas

2014-01-01

31

Exploring the nature of collisionless shocks under laboratory conditions  

PubMed Central

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

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

2014-01-01

32

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

PubMed

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

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

2014-11-01

33

Impact of hairy vetch cover crop on herbicide transport under field and laboratory conditions.  

PubMed

This study was conducted to evaluate the effect of hairy vetch cover crop residue on runoff losses of atrazine and metolachlor under both no-till corn field plots and from a laboratory runoff system. A 2-year field study was conducted in which losses of atrazine and metolachlor from vetch and non-vetch field plots were determined from the first runoff event after application (5 and 25 days after application in 1997 and 1998, respectively). A laboratory study was conducted using soil chambers, designed to simulate field soil, water, vegetation, and herbicide treatment conditions, subjected to simulated rain events of 5, 6, 20 and 21 days after application, similar to the rainfall pattern observed in the field study. Atrazine losses ranged from 1.2 to 7.2% and 0.01 to 0.08% and metolachlor losses ranged from 0.7 to 3.1% and 0.01 to 0.1% of the amount applied for the 1997 and 1998 runoff events, respectively. In the laboratory study, atrazine runoff losses ranged from 6.7 to 22.7% and 4.2 to 8.5% and metolachlor losses ranged from 3.6 to 9.8% and 1.1 to 4.7% of the amount applied for the 5-6 and 20-21 day events, respectively. The lower losses from the field study were due to smaller rainfall amounts and a series of small rains prior to the runoff event that likely washed herbicides off crop residue and into soil where adsorption could occur. Runoff losses of both herbicides were slightly higher from non-vetch than vetch field plots. Losses from the laboratory study were related to runoff volume rather than vegetation type. PMID:11444292

Sadeghi, A M; Isensee, A R

2001-07-01

34

Carbofuran promotes biochemical changes in carp exposed to rice field and laboratory conditions.  

PubMed

Effects of carbofuran commercial formulation on oxidative stress parameters were studied in carps (Cyprinus carpio) exposed to 50µg/L for 7 and 30 days under rice field and laboratory conditions. Thiobarbituric acid reactive substance (TBARS) levels were increased in the brain of fish after 7 and 30 days under rice field and laboratory conditions. In the liver and muscle, TBARS levels increased after 7 and 30 days under laboratory conditions, whereas in rice field the levels increased only after 30 days. Protein carbonyl content in the liver increased after 7 and 30 days under both experimental conditions. Acetylcholinesterase (AChE) activity was decreased in the brain and muscle after 7 and 30 days under both experimental conditions evaluated. The superoxide dismutase (SOD) activity increased in the liver after 7 and 30 days under rice field condition, whereas under laboratory condition this enzyme increased only after 30 days. The catalase (CAT) activity in the liver decreased after 30 days under rice field condition, whereas no changes were observed under laboratory conditions. In rice field, glutathione S-transferase (GST) decreased after 7 days but increased after 30 days, whereas no change was observed in fish exposed to carbofuran under laboratory conditions. These results suggest that environmental relevant carbofuran concentrations may cause oxidative stress, affecting biochemical and enzymatic parameters on carps. Some parameters could be used as biomarkers to carbofuran exposure. PMID:24507130

Clasen, Bárbara; Leitemperger, Jossiele; Murussi, Camila; Pretto, Alexandra; Menezes, Charlene; Dalabona, Fabrícia; Marchezan, Enio; Adaime, Martha Bohrer; Zanella, Renato; Loro, Vania Lucia

2014-03-01

35

Can natural phenotypic variances be estimated reliably under homogeneous laboratory conditions?  

E-print Network

and four size traits of neonates from eggs incubated in the laboratory and those left in situ. Mean size turtles (Chelydra serpentina) to a split-family design to evaluate the variability in incubation time measurements were similar between the laboratory and the field, but incubation time was systematically longer

Janzen, Fredric

36

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

NASA Technical Reports Server (NTRS)

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

Steffes, P. G.

1985-01-01

37

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

2013-01-01

38

Analyzing Fault Gouge Under Seismic Conditions in Laboratory Experiments  

NASA Astrophysics Data System (ADS)

The slip along a fault zone during an earthquake is associated with dense granular flow of the fault gouge. The gouge is a mixture of powder formed during prior slip as well as the dynamic rupture in the process zone of the propagating earthquake. Experimental tests of dense granular flow are usually conducted under low to moderate shear-rates and under low to vanishing normal stresses, and commonly without confinement. These experimental conditions do not match the conditions of natural earthquakes: slip of a few meters; normal stress of tens to hundreds MPa; slip velocity of ~1 m/s; rise time < 1 sec; and elevated, undrained fluid pressure. We build an apparatus for testing the mechanical behavior of fault gouge (and other dense granular materials) under these natural conditions. The apparatus has the following capabilities: (1) Control of fluid pore pressure in the gouge by leak-proof design for dry, wet, or partially saturated experiments, and control of pore pressure in wet experiments; (2) Continuously variable speed control 0.01- 1.5 m/s: (3) Cumulative slip up to 10 m; (4) Normal stress up to 30 MPa; (5) fast step-loading (short rise- time); and (6) Testing either gouge or solid rocks. We use this instrument to test weakening mechanisms during earthquake slip. Preliminary experimental results will be presented.

Reches, Z.; Lockner, D. A.; Young, J.; Eshkol, E.; Hamilton, M. E.; Fagan, J.

2008-12-01

39

Extracting phosphoric iron under laboratorial conditions smelting bog iron ores  

NASA Astrophysics Data System (ADS)

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

Török, B.; Thiele, A.

2013-12-01

40

Weathering rates of marble in laboratory and outdoor conditions  

SciTech Connect

In the modern urban atmosphere SO{sub 2} and NO{sub 2} attack calcite (CaCO{sub 3}) in marble exposed at rain-sheltered surfaces creating largely gypsum (CaSO{sub 4}{center_dot}2H{sub 2}O) crusts that eventually exfoliate. In combination with CO{sub 2} these gases erode the marble at unsheltered surfaces. the authors report the development of mathematical models to predict the rate of growth of crust and the rate of surface recession. To determine the rate of growth of crust the kinetic rate constant, diffusion rate, and the order of reaction were determined by the application of the shrinking-core model applied to data generated in laboratory experiments. Based on these parameters /and average ambient levels of 10 parts per billion (ppb) SO{sub 2} and 25 ppb NO{sub 2} in Louisville, Ky., the rate of crust formation for this metro area was calculated to be 1.8 {micro}m in the first year. However, the rate of recession was modeled from data obtained by exposing marble slabs to rainfalls. A surface recession of 15 {micro}m/yr was calculated. The models predicted well the rate of growth of crust observed at several sites in Louisville and the predicted surface recession compared well with values reported in the literature.

Yerrapragada, S.S.; Chirra, S.R.; Jaynes, J.H.; Bandyopadhyay, J.K.; Gauri, K.L. [Univ of Louisville, KY (United States); Li, S. [Metro Services Lab., Louisville, KY (United States)

1996-09-01

41

Development and application of a preference test system to evaluate housing conditions for laboratory rats  

Microsoft Academic Search

Improved knowledge of the ethological needs of laboratory animals can be used not only to verify current guidelines on laboratory animal housing, but also to refine these guidelines if desirable. Carefully chosen experiments can provide valid information about preferences or aversions towards specific housing conditions. The results of preference tests should be interpreted carefully and considered with results from direct

H. J. M. Blom; G. Van Tintelen; V. Baumans; J. Van Den Broek; A. C. Beynen

1995-01-01

42

Training of astronauts in laboratory-aircraft under weightless conditions for work in space  

NASA Technical Reports Server (NTRS)

Analyses of occupational activities of astronauts in laboratory-aircraft flights simulating weightlessness conditions permit the development of training methods and optimization of the interaction of man with various spacecraft designs.

Khrunov, Y. V.; Chekidra, I. F.; Kolosov, I. A.

1975-01-01

43

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 -7°C and -13°C, 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 -10°C. For temperatures below -10°C, 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.

ÁVila, Eldo E.; Lighezzolo, Rafael A.; Castellano, Nesvit E.; Pereyra, Rodolfo G.; Bürgesser, Rodrigo E.

2013-06-01

44

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

NASA Astrophysics Data System (ADS)

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

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

2012-06-01

45

Cross-polarization microwave radar return at severe wind conditions: laboratory model and geophysical model function.  

NASA Astrophysics Data System (ADS)

Satellite remote sensing is one of the main techniques of monitoring severe weather conditions over the ocean. The principal difficulty of the existing algorithms of retrieving wind based on dependence of microwave backscattering cross-section on wind speed (Geophysical Model Function, GMF) is due to its saturation at winds exceeding 25 - 30 m/s. Recently analysis of dual- and quad-polarization C-band radar return measured from satellite Radarsat-2 suggested that the cross-polarized radar return has much higher sensitivity to the wind speed than co-polarized back scattering [1] and conserved sensitivity to wind speed at hurricane conditions [2]. Since complete collocation of these data was not possible and time difference in flight legs and SAR images acquisition was up to 3 hours, these two sets of data were compared in [2] only statistically. The main purpose of this paper is investigation of the functional dependence of cross-polarized radar cross-section on the wind speed in laboratory experiment. Since cross-polarized radar return is formed due to scattering at small-scale structures of the air-sea interface (short-crested waves, foam, sprays, etc), which are well reproduced in laboratory conditions, then the approach based on laboratory experiment on radar scattering of microwaves at the water surface under hurricane wind looks feasible. The experiments were performed in the Wind-wave flume located on top of the Large Thermostratified Tank of the Institute of Applied Physics, where the airflow was produced in the flume with the straight working part of 10 m and operating cross section 0.40?0.40 sq. m, the axis velocity can be varied from 5 to 25 m/s. Microwave measurements were carried out by a coherent Doppler X-band (3.2 cm) scatterometer with the consequent receive of linear polarizations. Experiments confirmed higher sensitivity to the wind speed of the cross-polarized radar return. Simultaneously parameters of the air flow in the turbulent boundary layer (friction velocity and roughness height) were retrieved by velocity profiling and subsequent data processing based on self-similarity of the turbulent boundary layer and 10-m wind speed was calculated. The wind wave field parameters in the flume were measured by three wire gauges. The measured data on wind waves were used for estimation of the short wave spectra and slope probability density function for "long waves" within composite Bragg theory of microwave radar return. Estimations showed that for co-polarized radar returns the difference between measurements and the predictions of the model is about 1-2 dB and it can be explained by our poor knowledge about the short wave part of the spectrum. For cross-polarized return the difference exceeds 10 dB, and it indicates that some non-Bragg mechanisms (short-crested waves, foam, sprays, etc) are responsible for the depolarization of the returned signal. It seems reasonable then to suppose that the cross-polarized radar return in X- and C-bands will demonstrate similar dependence on wind speed. We compared the dependence of cross-polarized X-band radar cross-section on 10-m wind speed obtained in laboratory conditions with the similar dependence obtained in [2] from the field data for C-band radar cross-section and found out that the laboratory data follow the median of the field data with the constant bias -11 dB. Basing on laboratory data an empirical polynomial geophysical model function was suggested for retrieving wind speed up to 40 m/s from cross-polarized microwave return, which is in good agreement with the direct measurements. This work was carried out under financial support of the RFBR (project codes ¹ 13-05-00865, 12-05-12093) and by grant from the Government of the Russian Federation (project code 11.G34.31.0048). References [1] B. Zhang, W. Perrie Bull. Amer. Meteor. Soc., 93, 531-541, 2012. [2] G.-J. van Zadelhoff, et.al. Atmos. Meas. Tech. Discuss., 6, 7945-7984, doi:10.5194/amtd-6-7945-2013, 2013.

Troitskaya, Yuliya; Abramov, Victor; Ermoshkin, Alexey; Zuikova, Emma; Kazakov, Vassily; Sergeev, Daniil; Kandaurov, Alexandr

2014-05-01

46

Sandy beach macrofaunal communities on the western coast of Portugal - Is there a steady structure under similar exposed conditions?  

NASA Astrophysics Data System (ADS)

The structure of macrofaunal communities at two similar exposed sandy beaches on the western coast of Portugal was monitored for approximately 18 months by sampling all the beach area, from the shoreline to the base of the dunes. The beaches' physical environment, as well as community density and composition, seasonal variations and the potential relationships between biological data and environmental parameters were studied. The two beaches had similar exposure to wave action, but differed in terms of sediment grain size, extent of the intertidal area, sediment moisture content and, especially, in the potential food availability in the form of allochthonous debris. Differences were observed with regard to the communities' structure, namely regarding composition and relative contribution of the dominant species. Seasonality, especially temperature variations, and the interaction between seasons and the beach zones (supralittoral vs. intertidal) also had a strong influence on communities: controlling dominant species' density and the horizontal distribution of the dominant species, and promoting a differential utilization of the beach by several resident macrofaunal animals. The present study allows the identification of key species in exposed sandy beaches of western Portugal and demonstrates that a steady community structure does not persist in the similarly exposed conditions observed, which may be mainly a response to distinct detritus subsidies, combined with differences in sediment grain size, sediment moisture content and extent of the intertidal area.

Gonçalves, Sílvia C.; Anastácio, Pedro M.; Pardal, Miguel A.; Cardoso, Patrícia G.; Ferreira, Susana M.; Marques, João C.

2009-03-01

47

Can natural phenotypic variances be estimated reliably under homogeneous laboratory conditions?  

PubMed

The phenotypic variance is assumed to be greater in a more heterogeneous environment. The validity of this assumption is important for microevolutionists to extrapolate results from the laboratory to field environments. We subjected clutches of eggs from common snapping turtles (Chelydra serpentina) to a split-family design to evaluate the variability in incubation time and four size traits of neonates from eggs incubated in the laboratory and those left in situ. Mean size measurements were similar between the laboratory and the field, but incubation time was systematically longer in the field. We found no tendency among clutches for hatchlings resulting from eggs incubated in laboratory or field environments to demonstrate greater variability. Also contrary to expectation, clutches that experienced greater thermal variation in the field did not exhibit greater variation in phenotypic traits. Consequently, extrapolating results from the laboratory to the field may not always be problematic for microevolutionary analyses. PMID:17584235

St Juliana, J R; Janzen, F J

2007-07-01

48

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

NASA Technical Reports Server (NTRS)

Laboratory measurements were conducted to evaluate properties of atmospheric gases under simulated conditions for the outer planets. A significant addition to this effort was the capability to make such measurements at millimeter wavelengths. Measurements should soon be completed on the millimeter wave absorption from ammonia under Jovian conditions. Also studied will be the feasibility of measuring the microwave and millimeter wave properties of phosphine (PH3) under simulated Jovian conditions. Further analysis and application of the laboratory results to microwave and millimeter wave absorption data for the outer planet, such as Voyager Radio Occultation experiments, will be pursued.

Steffes, Paul G.

1987-01-01

49

Similarities Between Cometary, Meteoritic, and Laboratory Analog Dust: Hints from the Attribution of the 10-micrometer Band  

NASA Astrophysics Data System (ADS)

It is well known that the infrared emission of many comets is characterized by a broad feature at 10 micrometers, that has been attributed to a Si-O stretching resonance in amorphous and/or hydrated silicate grains. In the case of comets Halley [1,2], Bradfield [3] and Levy [4] two spectral components have been observed: the wide peak centered at 9.8 micrometers and a sharp feature at 11.3 micrometers. This last band has been interpreted with crystalline olivine silicatic grains [1,2,5]. However, recently, it has been pointed out [6] that the laboratory data frequently used in the fits refer to grains embedded in a matrix, which should produce a significant shift of the peak position, according to Mie computations. We have performed laboratory experiments on various silicatic samples with the perspective of determining their optical properties, to study experimentally the influence of matrix effects, and to use the final spectra to perform comparisons with observations. The samples are four terrestrial materials, olivine forsterite, jadeite pyroxene, andesite feldspar and impactite glass, and two meteoritic samples, chondrite (Zacatecas, Mexico) and pallasite (Atacama, Chile). Fine powders of the bulk materials were obtained by grinding calibrated mass amounts of the various samples in an agata mill. The morphological characterization of the samples was performed by means of S.E.M. (scanning electron microscopy) technique. EDX analysis was also performed to determine elemental composition. IR transmission spectra were obtained by using a double beam spectrophotometer that covers the spectral range 2.5-50 micrometers. The standard pellet technique was used by embedding dust samples in KBr or CsI matrices. For comparison, measurements were also performed by depositing small amounts of dust onto KBr windows. In this last case, dust-matrix interaction should be practically absent as grains are simply sitting onto the matrix. The data obtained from the spectroscopic analysis have allowed us to evidence the following main results. Matrix effects do not appear as relevant as suggested by computations performed by the Mie theory. In particular, the peak shift observed for crystalline olivine is from 11.3 micrometers in CsI (n(sub)o = 1.7) to 11.2 micrometers in vacuum (n(sun)o = 1.0). On the other hand, jadeite and andesite grains present main peaks around 10 micrometers, in contrast to cometary spectra. We can, therefore, conclude that crystalline olivine grains are good candidates to simulate the cometary 11.3 micrometer sharp feature, even when matrix effects are accounted for. The impactite sample presents a main broad band around 9.2 micrometers, due to its mainly amorphous composition. This band could resemble the broad 10 micron cometary band; however, its profile is rather broader than that observed for cometary dust. Concerning the meteoritic samples, both chondrite and pallasite show a well defined main peak at 11.3-11.4 micrometers, comparable to cometary spectra. Again, chondrite band profile is too broad. On the contrary, pallasite appears to be a good candidate to reproduce observations. This result appears reasonable if one considers that the sample is formed by small olivine crystals embedded in a iron matrix. In conclusion, the comparison between the spectra of olivine-rich meteoritic grains and cometary dust could suggest either a common origin of the two classes of materials or, at least, a similarity in the processes experienced by them during past evolution. This result appears very relevant because it could imply that the systematic study in the laboratory of meteoritic materials can provide information about the past history of comets. Acknowledgements: This work was partly supported by ASI, CNR, and MURST 40% and 60%. References: [1] Bregman J. D. et al. (1987) Astron. Astrophys., 187, 616. [2] Campins H. and Ryan E. V. (1989) Ap. J., 341, 1059. [3] Hanner M. S. et al. (1990) Ap. J., 348, 312. [4] Lynch D. K. et al. (1990) 22nd annual meeting of the division for planetary sciences, Charlottesville, Virgin

Colangeli, L.; Mennella, V.; Bussoletti, E.; Merluzzi, P.; Rotundi, A.; Palumbo, P.; di Marino, C.

1993-07-01

50

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

PubMed Central

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

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

2000-01-01

51

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

USGS Publications Warehouse

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

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

1981-01-01

52

FGFR3-related condition: a skeletal dysplasia with similarities to thanatophoric dysplasia and SADDAN due to Lys650Met.  

PubMed

Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene account for six related skeletal dysplasia conditions: achondroplasia, hypochondroplasia, thanatophoric dysplasia types 1 and 2, SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans), and platyspondylic lethal skeletal dysplasia, San Diego type. This group of disorders has very characteristic clinical and radiologic features, which distinguish them from other skeletal dysplasias. They display a spectrum of severity in the skeletal findings, ranging from relatively mild hypochondroplasia to lethal thanatophoric dysplasia. We report a patient who has the missense FGFR3 mutation, Lys650Met, previously reported in association only with SADDAN, who exhibits some findings similar to both thanatophoric dysplasia (types 1 and 2) in addition to those findings characteristic of SADDAN. PMID:25119967

Farmakis, Shannon G; Shinawi, Marwan; Miller-Thomas, Michelle; Radmanesh, Alireza; Herman, Thomas E

2015-03-01

53

Particle flows in a dc discharge in laboratory and microgravity conditions  

E-print Network

We describe a series of experiments on dust particles flows in a positive column of a horizontal dc discharge operating in laboratory and microgravity conditions. The main observation is that the particle flow velocities in laboratory experiments are systematically higher than in microgravity experiments, for otherwise identical discharge conditions. The paper provides an explanation for this interesting and unexpected observation. The explanation is based on a physical model, which properly takes into account main plasma-particle interaction mechanisms relevant to the described experimental study. Comparison of experimentally measured particle velocities and those calculated using the proposed model demonstrates reasonable agreement, both in laboratory and microgravity conditions, in the entire range of discharge parameters investigated.

Khrapak, S A; Chaudhuri, M; Morfill, G E; Zobnin, A V; Usachev, A D; Petrov, O F; Fortov, V E

2013-01-01

54

Mating frequency of the male cactus moth Cactoblastis cactorum (Lepidoptera:Pyralidae), under laboratory conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study evaluated the number of times that males of the invasive cactus moth Cactoblastis cactorum (Berg) mate under laboratory conditions. Virgin females were provided to each male at 24 h intervals until male death. Females removed from the containers were dissected to ascertain their mating ...

55

Recreation of Marine Atmospheric Corrosion Condition on Weathering Steel in Laboratory  

NASA Astrophysics Data System (ADS)

Salt spray test, autoclave corrosion test, SO2 salt spray test, and Relative humidity test are generally used to assess atmospheric corrosion in laboratories at accelerated rates. However, no test can absolutely simulate the service condition. One can get only approximate corrosion rates using the aforesaid tests which serve as an indicative of corrosion behavior of the material in a service condition. The present work is aimed at creating specific environmental condition in laboratory to get the corrosion test done in short duration to compare with on field exposure test which would otherwise take years to complete. In this work recreation of atmospheric environment of Digha was tried and it was simulated in such a manner that the results of laboratory test could be compared with long time field exposure at Digha. Weathering steel (WS) was taken for experimentations. Potentiostatic electrochemical tests route was adopted to simulate atmospheric condition of Digha. Laboratory test results compared well with 18 month field exposure data in terms of corrosion rate, SEM and Ramon Spectroscopy matching.

Guchhait, S. K.; Dewan, S.; Saha, J. K.; Mitra, P. K.

2014-04-01

56

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

NASA Astrophysics Data System (ADS)

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

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

2003-01-01

57

Fludarabine Melphalan reduced-intensity conditioning allotransplanation provides similar disease control in lymphoid and myeloid malignancies: analysis of 344 patients.  

PubMed

This was an Australasian Bone Marrow Transplant Recipient Registry (ABMTRR)-based retrospective study assessing the outcome of Fludarabine Melphalan (FluMel) reduced-intensity conditioning between 1998 and 2008. Median follow-up was 3.4 years. There were 344 patients with a median age of 54 years (18-68). In all, 234 patients had myeloid malignancies, with AML (n=166) being the commonest indication. There were 110 lymphoid patients with non-hodgkins lymphoma (NHL) (n=64) the main indication. TRM at day 100 was 14% with no significant difference between the groups. OS and disease-free survival (DFS) were similar between myeloid and lymphoid patients (57 and 50% at 3 years, respectively). There was no difference in cumulative incidence of relapse or GVHD between groups. Multivariate analysis revealed four significant adverse risk factors for DFS: donor other than HLA-identical sibling donor, not in remission at transplant, previous autologous transplant and recipient CMV positive. Chronic GVHD was associated with improved DFS in multivariate analysis predominantly due to a marked reduction in relapse (HR:0.44, P=0.003). This study confirms that FluMel provides durable and equivalent remissions in both myeloid and lymphoid malignancies. Disease stage and chronic GVHD remain important determinants of outcome for FluMel allografting. PMID:24056743

Bryant, A; Nivison-Smith, I; Pillai, E S; Kennedy, G; Kalff, A; Ritchie, D; George, B; Hertzberg, M; Patil, S; Spencer, A; Fay, K; Cannell, P; Berkahn, L; Doocey, R; Spearing, R; Moore, J

2014-01-01

58

Hydrochemical differences between Carpathian streams with similar physico-geographical conditions of catchments (the Polish Flysch Carpathians)  

NASA Astrophysics Data System (ADS)

The study was conducted during one hydrological year (2012/2013) in two Jaszcze and Jamne catchments (11.39 km2 and 8.95 km2, respectively) located in the Gorce Mountains with environmental features representative for the Western Flysch Carpathians (in 2012/2013 hydrological year). The Jaszcze and Jamne streams (9.3 km and 6.4 km long, respectively), are left tributaries of the Ochotnica river. Both catchments are in the range of the Magura nappe of the Carpathian Flysch. The Jaszcze and Jamne valleys are located in two climatic vertical zones: 1) a temperate cold zone (of a mean annual temperature of 4-6 ºC) and 2) a cold zone (2-4ºC), above 1,100 m a.s.l. Mean annual precipitation for this region in the years 1958-2008 was 841 mm. The aim of the research was to determine differences in the physicochemical properties between streams, the valleys of which are characterised by similar physico-geographical conditions. The discussed valleys are alike because of their proximity, and the similarity manifests itself through the occurrence of the same geology, relief and exposure of both valleys, as well as inclination and soil cover. The climatic conditions and circulation of groundwater are also similar. In both valleys, forest is the dominant land use form (the Jaszcze catchment - 77% and the Jamne - 55%). The research showed that the Jaszcze stream is characterised by a higher discharge throughout the year than the Jamne stream. In spring, the mean water flow rate calculated for the entire longitudinal profile of the Jaszcze stream was 1.6 times higher than the rate obtained for the Jamne stream. In summer and autumn, this rate was respectively 1.8 and 2.2 times higher in the Jaszcze stream than in the Jamne stream. The mean annual temperature of water in the Jamne stream is higher by 0.8 °C than the temperature of water in the Jaszcze stream. This is caused by the higher temperature of groundwater (even by up to 2-3 °C) and the lower discharge (the temperature increases more quickly). The pH values in the Jaszcze and Jamne streams show only slight variation in the annual cycle and along the longitudinal profiles of the streams, and amount to 8.4-8.9. The Jamne stream, due to the lower discharge, is also characterised by greater conductivity of water in comparison to the Jaszcze stream. The mean value of conductivity of water in the Jamne stream is higher throughout year by around 60 microsiemens. During the 2012/2013 hydrological year, the total mineralization of water in the Jamne stream was greater than in the Jaszcze stream. The differences in the values ranged from 4.65 mg/l (in spring) to 13.88 mg/l (in autumn). The analysis of chemical composition showed that apart from the bicarbonate ions, the water in the Jaszcze and Jamne streams is rich in calcium and sulphates ions. The study also observed a relatively large percentage of iron ions in the overall chemical composition. The project is funded by the National Science Center (NN 306 659 940).

Buca?a, Anna; Wiejaczka, ?ukasz

2014-05-01

59

Longevity and survival curves of Rhinella icterica (Anura, Bufonidae) under laboratory conditions.  

PubMed

Life tables and survival curves of tadpoles from Rhinella icterica species were studied in the laboratory, under abiotic conditions controlled by a purification filter, a timer and a chiller. The survival curve for larval stage confirms a great mortality trend in the initial stages, which decreases when reaching the mature morphological condition (r = -0.94). Stages 37, 38, 39, 40 and 41 showed gradual values for their age structures, while stages 42, 43 and 44 presented high variations. Based on the results under laboratory conditions, it can be concluded that the maturity of R. icterica tadpoles development between 37 and 44 stages has a negative correlation and their predicted life expectancy is a logarithmic growth curve (y=-761.96Ln(x)+5298.5). PMID:25166328

Lima, M S C S; Pederassi, J; Souza, C A S

2014-05-01

60

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

NASA Technical Reports Server (NTRS)

Laboratory measurements of microwave and millimeter wave properties of the simulated atmosphere of the outer planets and their satellites has continued. One of the focuses is on the development of a radiative transfer model of the Jovian atmosphere at wavelengths from 1 mm to 10 cm. This modeling effort led to laboratory measurements of the millimeter wave opacity of hydrogen sulfide (H2S) under simulated Jovian conditions. Descriptions of the modeling effort, the Laboratory experiment, and the observations are presented. Correlative studies of measurements with Pioneer-Venus radio occultation measurements with longer wavelength emission measurements have provided new ways for characterizing temporal and spatial variations in the abundance of both gases H2SO4 and SO2, and for modeling their roles in the subcloud atmosphere. Laboratory measurements were conducted on 1.35 cm (and 13 cm) opacity of gaseous SO2 and absorptivity of gaseous SO2 at the 3.2 mm wavelength under simulated Venus conditions. Laboratory measurements were completed on millimeter wave dielectric properties of liquid H2SO4, in order to model the effects of the opacity of the clouds of Venus onto millimeter wave emission spectrum.

Steffes, Paul G.

1991-01-01

61

The effects of changing deposition conditions on the similarity of sputter-deposited fluorocarbon thin films to bulk PTFE  

NASA Astrophysics Data System (ADS)

Solid lubrication of space-borne mechanical components is essential to their survival and the continued human exploration of space. Recent discoveries have shown that PTFE when blended with alumina nanofillers exhibits greatly improved physical performance properties, with wear rates being reduced by several orders of magnitude. The bulk processes used to produce the PTFE-alumina blends are limiting. Co-sputter deposition of PTFE and a filler material overcomes several of these limitations by enabling the reduction of particle size to the atomic level and also by allowing for the even coating of the solid lubricant on relatively large areas and components. The goal of this study was to establish a baseline performance of the sputtered PTFE films as compared to the bulk material, and to establish deposition conditions that would result in the most bulk-like film possible. In order to coax change in the structure of the sputtered films, sputtering power and deposition temperature were increased independently. Further, post-deposition annealing was applied to half of the deposited film in an attempt to affect change in the film structure. Complications in the characterization process due to increasing film thickness were also examined. Bulk-like metrics for characterization processes the included Fourier transform infrared spectroscopy (FTIR), X-ray spectroscopy (XPS), nanoindentation via atomic force microscopy, and contact angle of water on surface measurements were established. The results of the study revealed that increasing sputtering power and deposition temperature resulted in an increase in the similarity between the fluorocarbon films and the bulk PTFE, at a cost of affecting the potential of the film thicknesses, either by affecting the deposition process directly, or by decreasing the longevity of the sputtering targets.

Zandona, Philip

62

Mechanical design, analysis, and laboratory testing of a dental implant with axial flexibility similar to natural tooth with periodontal ligament.  

PubMed

At the interface between the jawbone and the roots of natural teeth, a thin, elastic, shock-absorbing tissue, called the periodontal ligament, forms a cushion which provides certain flexibility under mechanical loading. The dental restorations supported by implants, however, involve comparatively rigid connections to the jawbone. This causes overloading of the implant while bearing functional loading together with neighboring natural teeth, which leads to high stresses within the implant system and in the jawbone. A dental implant, with resilient components in the upper structure (abutment) in order to mimic the mechanical behavior of the periodontal ligament in the axial direction, was designed, analyzed in silico, and produced for mechanical testing. The aims of the design were avoiding high levels of stress, loosening of the abutment connection screw, and soft tissue irritations. The finite element analysis of the designed implant revealed that the elastic abutment yielded a similar axial mobility with the natural tooth while keeping stress in the implant at safe levels. The in vitro mechanical testing of the prototype resulted in similar axial mobility predicted by the analysis and as that of a typical natural tooth. The abutment screw did not loosen under repeated loading and there was no static or fatigue failure. PMID:25378380

Pekta?, Ömer; Tönük, Ergin

2014-11-01

63

Laboratory versus industrial cutting force sensor in tool condition monitoring system  

NASA Astrophysics Data System (ADS)

Research works concerning the utilisation of cutting force measures in tool condition monitoring usually present results and deliberations based on laboratory sensors. These sensors are too fragile to be used in industrial practice. Industrial sensors employed on the factory floor are less accurate, and this must be taken into account when creating a tool condition monitoring strategy. Another drawback of most of these works is that constant cutting parameters are used for the entire tool life. This does not reflect industrial practice where the same tool is used at different feeds and depths of cut in sequential passes. This paper presents a comparison of signals originating from laboratory and industrial cutting force sensors. The usability of the sensor output was studied during a laboratory simulation of industrial cutting conditions. Instead of building mathematical models for the correlation between tool wear and cutting force, an FFBP artificial neural network was used to find which combination of input data would provide an acceptable estimation of tool wear. The results obtained proved that cross talk between channels has an important influence on cutting force measurements, however this input configuration can be used for a tool condition monitoring system.

Szwajka, K.

2005-01-01

64

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

NASA Technical Reports Server (NTRS)

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

Steffes, Paul G.

1987-01-01

65

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...

66

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

67

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

NASA Technical Reports Server (NTRS)

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

Steffes, P. G.

1985-01-01

68

Transmission of Demodex flagellurus (Acari: Demodicidae) in the house mouse, Mus musculus , under laboratory conditions  

Microsoft Academic Search

Transmission ofDemodex flagellurus Bukva, 1985 inhabiting the preputial and clitoral glands of the house mouse,Mus musculus L., was studied in mating experiments using pairs of infested, feralXmite-free, white laboratory mice. Spontaneous transfer of mites between sexually active hosts of the opposite sex, presumably through copulation, is reported for the first time for the hair-follicle mites under controlled conditions. Transfer of

V. Bukva

1990-01-01

69

Breeding of wild-caught rodent cricetidae Holochilus brasiliensis under laboratory conditions.  

PubMed

The breeding of wild-caught rodent Holochilus brasiliensis (Desmarest, 1819) was studied under laboratory conditions. The mean gestation length was 28.4 days. Litter size ranged from one to five. Males matured at 2-3 months and females at 2-4.5 months of age. The oestrous cycle lasted 6-8 days. Eleven pairs observed over 6-13 months increased to a population of 276 individuals (153 males and 123 females). PMID:3540447

Mello, D A

1986-07-01

70

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 (50°C, 21°C, 5°C, and -10°C) 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

71

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

72

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

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and earth-based radio astronomical observations can be used to infer abundances of microwave absorbing 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.

1997-01-01

73

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

NASA Astrophysics Data System (ADS)

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

Marcucci, Emma C.; Hynek, Brian M.

2014-03-01

74

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

75

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

2011-05-01

76

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

SciTech Connect

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{sub 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.

Abichou, Tarek, E-mail: abichou@eng.fsu.edu [Florida State University, Tallahassee, FL 32311 (United States); Mahieu, Koenraad; Chanton, Jeff [Florida State University, Tallahassee, FL 32311 (United States); Romdhane, Mehrez; Mansouri, Imane [Unite de Recherche M.A.C.S., Ecole Nationale d'Ingenieurs de Gabes, Route de Medenine, 6029 Gabes (Tunisia)

2011-05-15

77

Laboratory rearing conditions for improved growth of juvenile Helix aspersa Müller snails.  

PubMed

A laboratory rearing system in semi-controlled conditions is proposed to facilitate the behavioural rhythms of the edible snail (Helix aspersa) and to produce a high growth rate with low variability. The growth data were used to construct a model for weight estimation based on age. The animals' live weights showed low variability (<17%) and normal distribution. The best model for estimating weight from age is the logistic model, with a high corelation coefficient (>90%), and a high level of significance for the coefficient (P < 0.0001). PMID:16803649

García, A; Perea, J M; Mayoral, A; Acero, R; Martos, J; Gómez, G; Peña, F

2006-07-01

78

Anaerobic growth of Candida albicans does not support biofilm formation under similar conditions used for aerobic biofilm.  

PubMed

C. albicans is an opportunistic fungus causing life-threatening systemic infections particularly in immunocompromised individuals. The organism is a commensal in humans and grows either aerobically, e.g., the oral cavity, or anaerobically, e.g., the gut. We studied anaerobic growth of C. albicans in a defined yeast nitrogen base dextrose medium after adaptation and subculturing in an anaerobic chamber. At 37 degrees C in suspension culture, much slower growth was observed anaerobically with a generation time of 248 min compared to 98 min for aerobic growth. Although the organism grew well on solid medium, shaking increased the growth rate in suspension culture at 37 degrees C. Growth was enhanced at acidic pH compared to neutral or alkaline pH. Cells grown anaerobically produced hyphae, but did not produce biofilm on plastic surface or denture acrylic under either static conditions or with mild shaking, conditions that support aerobic biofilm formation. PMID:15991052

Biswas, Swarajit K; Chaffin, W LaJean

2005-08-01

79

Dynamics of genetic variability in Anastrepha fraterculus (Diptera: Tephritidae) during adaptation to laboratory rearing conditions  

PubMed Central

Background Anastrepha fraterculus is one of the most important fruit fly plagues in the American continent and only chemical control is applied in the field to diminish its population densities. A better understanding of the genetic variability during the introduction and adaptation of wild A. fraterculus populations to laboratory conditions is required for the development of stable and vigorous experimental colonies and mass-reared strains in support of successful Sterile Insect Technique (SIT) efforts. Methods The present study aims to analyze the dynamics of changes in genetic variability during the first six generations under artificial rearing conditions in two populations: a) a wild population recently introduced to laboratory culture, named TW and, b) a long-established control line, named CL. Results Results showed a declining tendency of genetic variability in TW. In CL, the relatively high values of genetic variability appear to be maintained across generations and could denote an intrinsic capacity to avoid the loss of genetic diversity in time. Discussion The impact of evolutionary forces on this species during the adaptation process as well as the best approach to choose strategies to introduce experimental and mass-reared A. fraterculus strains for SIT programs are discussed. PMID:25471362

2014-01-01

80

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

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments, entry probe radio signal absorption measurements, and earth-based 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 taken under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. For example, laboratory measurements completed recently by Kolodner and Steffes (ICARUS 132, pp. 151-169, March 1998, attached as Appendix A) under this grant (NAGS-4190), have shown that the opacity from gaseous H2SO4 under simulated Venus conditions is best described by a different formalism than was previously used. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both spacecraft entry probe and orbiter radio occultation experiments and by radio astronomical observations, and over a range of frequencies which correspond to those used in such experiments, 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.

1998-01-01

81

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

82

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

83

Redox conditions and the efficiency of chlorinated ethene biodegradation: Laboratory studies  

USGS Publications Warehouse

The potential for biodegradation of highly reduced groundwater contaminants is greatest under aerobic conditions and least under CO2-reducing (methanogenic) conditions. Laboratory studies conducted using [1,2-14C] vinyl chloride (VC) indicate the same pattern applies to the anaerobic oxidation of relatively reduced chloroethylenes. Recent studies, showing that CH4 can be a significant product of microbial degradation of VC under methanogenic conditions, clarified mechanisms underlying anaerobic VC mineralization and emphasized the redox dependence of this process. A microcosm study conducted with stream bed sediments demonstrated rapid degradation of [1,2-14C] VC and simultaneous production of 14CO2 and 14CH4. The results of acetate mineralization studies indicated that these sediments contained active acetotrophic methanogens. VC degradation involved an initial transformation to acetate via oxidative acetogenesis followed by acetotrophic methanogenesis to yield CO2 and CH4 as final products. Based on these recent results, a conceptual model for anaerobic microbial degradation of VC to non-chlorinated products can be proposed.

Bradley, P.M.; Chapelle, F.H.

2000-01-01

84

A Comprehensive Subcellular Proteomic Survey of Salmonella Grown under Phagosome-Mimicking versus Standard Laboratory Conditions  

PubMed Central

Towards developing a systems-level pathobiological understanding of Salmonella enterica, we performed a subcellular proteomic analysis of this pathogen grown under standard laboratory and phagosome-mimicking conditions in vitro. Analysis of proteins from cytoplasmic, inner membrane, periplasmic, and outer membrane fractions yielded coverage of 25% of the theoretical proteome. Confident subcellular location could be assigned to over 1000 proteins, with good agreement between experimentally observed location and predicted/known protein properties. Comparison of protein location under the different environmental conditions provided insight into dynamic protein localization and possible moonlighting (multiple function) activities. Notable examples of dynamic localization were the response regulators of two-component regulatory systems (e.g., ArcB and PhoQ). The DNA-binding protein Dps that is generally regarded as cytoplasmic was significantly enriched in the outer membrane for all growth conditions examined, suggestive of moonlighting activities. These observations imply the existence of unknown transport mechanisms and novel functions for a subset of Salmonella proteins. Overall, this work provides a catalog of experimentally verified subcellular protein locations for Salmonella and a framework for further investigations using computational modeling. PMID:22900174

Brown, Roslyn N.; Sanford, James A.; Park, Jea H.; Deatherage, Brooke L.; Champion, Boyd L.; Smith, Richard D.; Heffron, Fred; Adkins, Joshua N.

2012-01-01

85

A Comprehensive Subcellular Proteomic Survey of Salmonella Grown under Phagosome-Mimicking versus Standard Laboratory Conditions  

SciTech Connect

Towards developing a systems-level pathobiological understanding of Salmonella enterica, we performed a subcellular proteomic analysis of this pathogen grown under standard laboratory and infection-mimicking conditions in vitro. Analysis of proteins from cytoplasmic, inner membrane, periplasmic, and outer membrane fractions yielded coverage of over 30% of the theoretical proteome. Confident subcellular location could be assigned to over 1000 proteins, with good agreement between experimentally observed location and predicted/known protein properties. Comparison of protein location under the different environmental conditions provided insight into dynamic protein localization and possible moonlighting (multiple function) activities. Notable examples of dynamic localization were the response regulators of two-component regulatory systems (e.g., ArcB, PhoQ). The DNA-binding protein Dps that is generally regarded as cytoplasmic was significantly enriched in the outer membrane for all growth conditions examined, suggestive of moonlighting activities. These observations imply the existence of unknown transport mechanisms and novel functions for a subset of Salmonella proteins. Overall, this work provides a catalog of experimentally verified subcellular protein location for Salmonella and a framework for further investigations using computational modeling.

Brown, Roslyn N.; Sanford, James A.; Park, Jea H.; Deatherage, Brooke L.; Champion, Boyd L.; Smith, Richard D.; Heffron, Fred; Adkins, Joshua N.

2012-06-01

86

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

PubMed

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

Fritt-Rasmussen, Janne; Brandvik, Per Johan

2011-08-01

87

Residual bioassay to assess the toxicity of Acaricides against Aceria guerreronis (Acari: Eriophyidae) under laboratory conditions.  

PubMed

Aceria guerreronis Keifer (Acari: Eriophyidae) is considered a major pest of the coconut (Cocos nucifera L.), and the use of pesticides is the current method to control it. However, no standard toxicological tests exist to select and assess the efficiency of molecules against the coconut mite. The aim of this study was to develop a methodology that allows for the evaluation of the relative toxicity of acaricides to A. guerreronis through rapid laboratory procedures. We confined A. guerreronis on arenas made out of coconut leaflets and tested two application methods: immersing the leaf fragments in acaricides and spraying acaricides on the leaf fragments under a Potter spray tower. In the latter application method, we sprayed leaf fragments both populated with and devoid of mites. We evaluated the comparative toxicity of two populations (Itamaracá and Petrolina, Pernambuco, Brazil) by spraying on leaflets without mites and submitted the mortality data to probit analysis after 24 h of exposure. No difference was observed in the LC50, regardless of whether the leaflets were immersed or sprayed with acaricide (abamectin, chlorfenapyr or fenpyroximate). The toxicity of chlorfenapyr and fenpyroximate did not differ, irrespective of whether it was applied directly to the leaflet or to the mite; however, the toxicity of abamectin was higher when applied directly to the mite. Chlorpyrifos and abamectin toxicities were lower for the Petrolina population than for the Itamaracá population. Immersing and spraying coconut leaflets can be used to assess the mortality of A. guerreronis under laboratory conditions. PMID:22928324

Monteiro, Vaneska B; Lima, Debora B; Gondim, Manoel G C; Siqueira, Herbert A A

2012-08-01

88

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

NASA Technical Reports Server (NTRS)

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

Steffes, Paul G.

1992-01-01

89

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

SciTech Connect

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

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

1986-08-01

90

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

NASA Astrophysics Data System (ADS)

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

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

2014-08-01

91

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

PubMed Central

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

Ozanne, Gérard; Huot, Roger; Montpetit, Claude

1993-01-01

92

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

93

Abilities of Helophyte Species to Release Oxygen into Rhizospheres with Varying Redox Conditions in Laboratory-Scale Hydroponic Systems  

Microsoft Academic Search

Plantlets of the wetland species cattail (Typha latifolia), reed (Phragmites australis), rush (Juncus effusus), and yellow flag (Iris pseudacorus) grown from seedlings or cuttings were investigated in laboratory-scale hydroponic systems in order to determine the intensity of oxygen release into the rhizosphere under various redox conditions. The initial redox conditions of the rhizosphere were modified by adding different amounts of

A. Wießner; P. Kuschk; M. Kästner; U. Stottmeister

2002-01-01

94

Cryogenic trapping of atmospheric organic acids under laboratory and field conditions  

NASA Astrophysics Data System (ADS)

A new and easy to handle method for the sampling of atmospheric organic acids is presented. The acids are cryogenically cotrapped with atmospheric water, using a specially designed siliconised glass trap, constantly cooled to - 70°C. A constant air flow is chosen ranging between 2 and 8 l min -1 Samples are analysed by ion chromatography. With this method several acids may be detected, such as formic, acetic, lactic, oxalic, propionic and pyruvic acids. Sampling efficiency was tested for formic and acetic acid for different sample volumes, sampling times and flow rates, all performed under typical ambient conditions (relative humidity 67 ± 3°; temperature 25.5 ± 0.5°C; mixing ratios: 0.87 ± 0.015 and 1.07 ± 0.023 ppbv for acetic acid and formic acid, respectively). For both acids sampling efficiency was found to be 100 (± 3)%. Errors for parallel samples were 3% maximum. ZEFLUOR filters, used to separate particles from the gas stream, showed no impact on the composition and concentration of formic, acetic and propionic acids, whereas oxalic acid showed severe losses on the filter. Field measurements confirmed the reliability of the method. Under varying field conditions the relative accuracy seemed to be lower than in the laboratory tests but still lied in a satisfying range. Typical concentrations (averages of field measurements) yield relative errors of 6.4% for formic acid, 6.1% for acetic acid and 7.1% for propionic acid.

Hofmann, U.; Weller, D.; Ammann, Ch.; Jork, E.; Kesselmeier, J.

95

Active personal dosemeters in interventional radiology: tests in laboratory conditions and in hospitals.  

PubMed

The work package 3 of the ORAMED project, Collaborative Project (2008-11) supported by the European Commission within its seventh Framework Programme, is focused on the optimisation of the use of active personal dosemeters (APDs) in interventional radiology and cardiology (IR/IC). Indeed, a lack of appropriate APD devices is identified for these specific fields. Few devices can detect low-energy X rays (20-100 keV), and none of them are specifically designed for working in pulsed radiation fields. The work presented in this paper consists in studying the behaviour of some selected APDs deemed suitable for application in IR/IC. For this purpose, measurements under laboratory conditions, both with continuous and pulsed X-ray beams, and tests in real conditions on site in different European hospitals were performed. This study highlights the limitations of APDs for this application and the need of improving the APD technology so as to fulfil all needs in the IR/IC field. PMID:21186215

Clairand, I; Bordy, J-M; Daures, J; Debroas, J; Denozière, M; Donadille, L; Ginjaume, M; Itié, C; Koukorava, C; Krim, S; Lebacq, A-L; Martin, P; Struelens, L; Sans-Mercé, M; Tosic, M; Vanhavere, F

2011-03-01

96

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

SciTech Connect

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

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

1989-07-02

97

The Formation of Sulfate and Elemental Sulfur Aerosols Under Varying Laboratory Conditions: Implications for Early Earth  

NASA Technical Reports Server (NTRS)

The presence of sulfur mass-independent fractionation (S-MIF) in sediments more than 2.45 x 10(exp 9) years old is thought to be evidence for an early anoxic atmosphere. Photolysis of sulfur dioxide (SO2) by UV light with lambda < 220 nm has been shown in models and some initial 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 (S8) and sulfuric acid (H2S04) aerosols. Here, we use real-time aerosol mass spectrometry to directly detect the sulfur-containing aerosols formed when SO2 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 (H2) or methane (CH4), increased the formation of S8. With UV photolysis, formation of S8 aerosols is highly dependent on the initial SO2 pressure; and S8 is only formed at a 2% SO2 mixing ratio and greater in the absence of a reductant, and at a 0.2% SO2 mixing ratio and greater in the presence of 1000 ppmv CH4. We also found that organosulfur compounds are formed from the photolysis of CH4 and moderate amounts of SO2, The implications for sulfur aerosols on early Earth are discussed.

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

2010-01-01

98

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

99

Temperature management during semen processing: Impact on boar sperm quality under laboratory and field conditions.  

PubMed

Freshly collected boar spermatozoa are sensitive to a fast reduction in temperature because of lipid phase transition and phase separation processes. Temperature management during semen processing may determine the quality of stored samples. The aim of this study was to evaluate the influence of isothermic and hypothermic semen processing protocols on boar sperm quality under laboratory and field conditions. In the laboratory study, ejaculates (n = 12) were first diluted (1:1) with Beltsville Thawing Solution (BTS) at 32 °C, then processed either with isothermic (32 °C) or hypothermic (21 °C) BTS, stored at 17 °C, and assessed on days 1, 3, and 6. Temperature curves showed that 150 minutes after the first dilution, semen doses of both groups reached the same temperature. Two-step hypothermic processing resulted in lower sperm motility on days 1 and 6 (P < 0.05). Concomitantly, hypothermally processed samples contained less membrane intact sperm on days 3 and 6 (P < 0.05). Using AndroStar Plus extender instead of BTS reduced the negative effect of hypothermic processing. In the field study, 15 semen samples from each of 23 European artificial insemination studs were evaluated as part of an external quality control program. Semen quality based on motility, membrane integrity, mitochondrial activity, and a thermoresistance test was higher for stations using one-step isothermic dilutions (n = 7) compared with artificial insemination centers using two-step hypothermic protocols (n = 16). Both studies show that chilling injury associated with hypothermic dilution results in lower quality of stored boar semen compared with isothermic dilution and that the type of semen extender affects the outcomes. PMID:23987989

Schulze, M; Henning, H; Rüdiger, K; Wallner, U; Waberski, D

2013-12-01

100

Conditions Similar to Alcohol Impairment  

E-print Network

paramedics to your position. Situations Requiring Emergency Transportation? · Heart attacks & severe chest for breathing movements. A rate of 12 20 breaths per minute is normal. Alcohol Poisoning · Other Possible Signs

Stuart, Steven J.

101

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

PubMed Central

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

2013-01-01

102

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

PubMed Central

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

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

2013-01-01

103

Effect of puddling intensity on physical properties of a silty clay soil under laboratory and field conditions  

Microsoft Academic Search

Conventional tillage and planting method for rice (Oryza sativa L.) production in northern Iran is wet tillage (puddling). Effect of different puddling intensities on physical properties\\u000a of a silty clay soil (Typic Haplodalfs) was investigated under laboratory and field conditions. Changes in soil physical parameters\\u000a and water requirement for puddling were measured. For laboratory experiments, undisturbed cylindrical soil samples (diameter

S. F. Mousavi; S. Yousefi-Moghadam; B. Mostafazadeh-Fard; A. Hemmat; M. R. Yazdani

2009-01-01

104

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

PubMed

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

Brar, Pardeepinder Kaur; Danyluk, Michelle D

2013-08-01

105

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

106

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

NASA Astrophysics Data System (ADS)

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

Bellotti, Amadeo; Steffes, Paul G.

2014-11-01

107

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

PubMed Central

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

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

2012-01-01

108

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 ¹/? and ¹/??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 (½ of LC??) of pretilachlor and pendimethalin, respectively. Juveniles of Xenylla welchi exposed to ¹/?, ¹/? and ¹/??th LC?? for pretilachlor (12.1, 9.1, 7.3 g a.i/ha) and ¹/? and ¹/??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

2011-06-01

109

Photochemical degradation of a brominated flame retardant (tetrabromobisphenol A) in ice under field and laboratory conditions  

NASA Astrophysics Data System (ADS)

Studies of brominated flame retardants have raised awareness of their potential environmental impact as toxic compounds. Because these compounds are now globally distributed, including in the Polar Regions, it is important to assess their potential fate in the environment. It has been shown that active photochemistry occurs in sunlit snow and ice, but there is little information regarding potential photochemical degradation of brominated flame retardants in snow and ice. The purpose of this research is to investigate the direct and indirect photochemical transformation pathways of a widely used brominated flame retardant, tetrabromobisphenol A (TBBPA). We have conducted field-based experiments in Barrow, Alaska to investigate the potential photochemical degradation of TBBPA in snow and ice under environmentally-relevant conditions. Field-based results show that TBBPA is efficiently degraded under direct photolysis conditions in frozen aqueous samples under natural Barrow sunlight. In aqueous solution the light absorption properties of TBBPA are pH dependent. Therefore, the photodegradation of TBBPA in snow and ice will be highly pH dependent. Reactions that are pH dependent may be affected by the nature of the liquid-like layers in snow/ice as well as the presence of other solutes that may indirectly affect the local pH experienced by TBBPA in snow and ice samples. In order to establish how the effective pH of liquid-like regions in ice might impact the degradation of TBBPA, various salts (sodium chloride, sodium fluoride, sodium bromide, ammonium chloride, ammonium acetate and ammonium sulfate) were added to aqueous solutions of TBBPA. Upon freezing, these different salts will induce pH differences in the liquid-like regions of the sample due to a phenomenon known as the freezing potential. Observed reactivity differences upon addition of these salts will be evaluated and discussed. Additionally, the presence of natural dissolved organic matter (DOM), an effective environmentally-relevant photosensitizer, has the potential to cause indirect photochemical degradation of TBBPA and this degradation pathway was also evaluated under laboratory conditions. The potential for both commercially-derived DOM and DOM isolated from Arctic snow samples to photosensitize TBBPA degradation in liquid and ice will be evaluated and discussed.

Waligroski, G.; Grannas, A. M.

2013-12-01

110

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

PubMed Central

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

2014-01-01

111

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

Microsoft Academic Search

A laboratory reactor planted with Juncus effusus treating an artificial wastewater was used to investigate the short-term and long-term variations and interactions in the redox conditions as well as the removal efficiency of C and the N turnover. The permanent circulation of the process water enabled the micro-gradient processes to be evaluated for an operating period of 20 months.Steady-state conditions

A. Wießner; U. Kappelmeyer; P. Kuschk; M. Kästner

2005-01-01

112

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

NASA Astrophysics Data System (ADS)

Amendments can control the runoff and soil loss by protecting the soil surface. However, scale effects on runoff and soil loss control have not been considered yet. The present study has been formulated to determine the efficiency of two plot sizes of 6 and 0.25 m2 covered by 0.5 kg m-2 of straw mulch with regard to changing the time to runoff, runoff coefficient, sediment concentration and soil loss under laboratory conditions. The study used a sandy-loam soil taken from summer rangeland, Alborz Mountains, northern Iran, and was conducted under simulated rainfall intensities of 50 and 90 mm h-1 and in three replicates. The results of the study showed that the straw mulch had a more significant effect on reducing the runoff coefficient, sediment concentration and soil loss on a 0.25 m2 plot scale. The maximum effectiveness in time to runoff for both the scales was observed at a rainfall intensity of 90 mm h-1. The maximum increasing and decreasing rates in time to runoff and runoff coefficient were observed at a rainfall intensity of 90 mm h-1, with 367.92 and 96.71% for the 0.25 m2 plot and 110.10 and 15.08% for the 6 m2 plot. The maximum reduction in the runoff coefficient was in the 0.25 m2 plot for the two rainfall intensities of 50 and 90 mm h-1, with rates of -89.34 and -96.71%. The maximum change in soil loss at the intensities of both 50 and 90 mm h-1 occurred in the 0.25 m2 plot, with 100%, whereas in the 6 m2 plot, decreasing rates of soil loss for the intensities of both 50 and 90 mm h-1 were 46.74 and 63.24%, respectively.

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

2015-01-01

113

A Comparison of Entomopathogenic Nematode Longevity in Soil under Laboratory Conditions  

PubMed Central

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

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

2006-01-01

114

Pre-processing of Xeva-XS imagery for determining spectral reflectance coefficients in laboratory conditions  

NASA Astrophysics Data System (ADS)

There are two different methodologies which can be used to acquire imagery from which it would be possible to obtain spectral reflectance characteristics - the first based on images of a scene in which a reference panel had been included, and the second based on precisely selected exposure parameters. This paper is concerned with the first of these two methods based on experiments conducted using a 14bit XEVA XS-1.7.320 infrared sensor. The paper firstly describes the effect of different exposure settings on the accuracy with which we can later determine the spectral reflectance coefficients. The next step when working with such imagery in laboratory conditions is to eliminate the effect of the uneven distribution of illumination. In the paper we present two proposed methods for eliminating the uneven distribution of illumination - an additive method and a quotient method. After that it is essential to stretch the DN values. Once again we investigated two possible methods of doing this - firstly, by stretching the data using only the white reference panel, adjusting the maxDN value of the image of the surface of the reference panel to 95%. The second method additionally adds a second reference point - a black reference panel which reflects 5% of incident radiation. The spectral reflectance coefficients of chosen samples acquired using all of the above mentioned methods are compared with reference data obtained using a spectroradiometer. Establishing the most optimal methodologies will greatly increase the accuracy of obtained spectral response coefficients, which at the same time will increase the accuracy with which, in this case, water pollutants will be identified.

Walczykowski, P.; Orych, A.; Kedzierski, M.; Fryskowska, A.

2014-11-01

115

Similarity Measures  

Microsoft Academic Search

With complex multimedia data, we see the emergence of database systems in which thefundamental operation is similarity assessment. Before database issues can be addressed, it isnecessary to give a definition of similarity as an operation.In this paper we develop a similarity measure, based on fuzzy logic, that exhibit severalfeatures that match experimental findings in humans. The model is dubbed Fuzzy

Simone Santini; Ramesh Jain

1999-01-01

116

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

EPA Science Inventory

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

117

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 ...

118

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 -21°C) 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 Student’s 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

119

Laboratory modelling of shear behaviour of soft joints under constant normal stiffness conditions  

Microsoft Academic Search

Shear behaviour of regular sawtooth rock joints produced from casting plaster are investigated under constant normal stiffness (CNS) conditions. Test results obtained in this investigation are also compared with the constant normal load (CNL) tests. It is observed that the peak shear stress obtained under CNL conditions always underestimates the peak shear stress corresponding to the CNS condition. Plots of

B. Indraratna; A. Haque; N. Aziz

1998-01-01

120

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

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The key activity for this grant year has continued to be laboratory measurements of the microwave and millimeter-wave properties of the simulated atmospheres of the outer planets and their satellites. A Fabry-Perot spectrometer system capable of operation from 32 to 41 GHz was developed. Initially this spectrometer was used to complete laboratory measurements of the 7.5 to 9.3 mm absorption spectrum of ammonia. Laboratory measurements were begun at wavelengths near 3.2 mm, where a large number of observations of the emission from the outer planets were made. A description of this system is presented.

Steffes, Paul G.

1988-01-01

121

Development, growth and survival of the larvae of queen conch Strombus gigas under laboratory conditions  

Microsoft Academic Search

The development, growth and survival of Strombus gigas (Linné, 1758) larvae were studied over a period of 30 days in laboratory culture. The fertilized egg masses used for the larval culture experiment were collected in Alacran's Reef from March to September. Experiments were conducted at 29±1 °C. Veligers were reared at 200 larvae l?1 in 4-l containers. Larvae were fed

Nancy Brito-Manzano; Dalila Aldana Aranda

2004-01-01

122

The effectiveness of mosquito coils containing esbiothrin under laboratory and field conditions.  

PubMed

Tests were made to correlate the chemical content of mosquito coils with the knockdown and bite-inhibitory action of the smoke in the laboratory and with the protective effect in field use. Smoke from a blank coil, containing no pyrethroid, gave no knockdown, 10% inhibition of biting in the laboratory using Aedes aegypti, and 39% protection in field tests in village huts on the Kenyan coast with a mixed population of mosquitoes including 71% Anopheles gambiae. Coils containing low experimental contents of 0.044% and 0.099% Esbiothrin, an isomer blend rich in the D-allethrolone ester of D-trans-chrysanthemic acid, gave rapid knockdown in both small chamber and 25 m3 room tests, and 71% and 94% inhibition of biting respectively in the laboratory. In the field they gave 74% and 84% protection from mosquitoes alighting. Chemical content was therefore a good guide to knockdown and bite inhibition in the laboratory and also to the considerable protection found in the field. PMID:2891344

Birley, M H; Mutero, C M; Turner, I F; Chadwick, P R

1987-04-01

123

A Comparison of Factors Involved in Starch Degradation in Barley Germination Under Laboratory and Malting Conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Grains of the malting barley cultivar Legacy were laboratory germinated (LG) or micromalted (MM) and sampled daily from 0 to 5 days after imbibition/steeping. Alpha-amylase and beta-amylase activities and protein levels along with starch, osmolyte concentration (OC), and sugar (glucose, sucrose, fr...

124

Conditions for Building a Community of Practice in an Advanced Physics Laboratory  

ERIC Educational Resources Information Center

We use the theory of communities of practice and the concept of accountable disciplinary knowledge to describe how a learning community develops in the context of an upper-division physics laboratory course. The change in accountable disciplinary knowledge motivates students' enculturation into a community of practice. The enculturation…

Irving, Paul W.; Sayre, Eleanor C.

2014-01-01

125

Effect of temperature on development and growth of the raptorial cladoceran Leptodora kindtii under laboratory conditions  

Microsoft Academic Search

1. Leptodora is a key species in many temperate freshwater systems, but so far its role in the food web could not be properly evaluated because detailed information about its secondary production was lacking. As we wanted to estimate the secondary production of Leptodora, we measured its development and growth rates in the laboratory. 2. Employing improved methods to estimate

Jacobus Vijverberg; Hans Peter Koelewijn

2004-01-01

126

Mating frequency of the male cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae), under laboratory conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study evaluated the effects of three constant temperatures (20°, 25° and 30°C) on the rate of development and life history of the invasive cactus moth Cactoblastis cactorum (Berg). Results from these laboratory experiments were used to predict C. cactorum rate of development in the field during...

127

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

EPA Science Inventory

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

128

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

PubMed Central

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

Aïzoun, Nazaire; Azondekon, Roseric; Aïkpon, Rock; Gnanguenon, Virgile; Osse, Razaki; Asidi, Alex; Akogbéto, Martin

2014-01-01

129

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

130

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

131

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

Microsoft Academic Search

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

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

2000-01-01

132

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

PubMed

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

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

2014-08-01

133

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

134

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

PubMed Central

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

Flores-Miranda, Brisa Marisol; Espinosa-Plascencia, Angelica; Gómez-Jiménez, Silvia; López-Zavala, Alonso Alexis; González-Carrillo, Haydé Hayamaí; Bermúdez-Almada, María del Carmen

2012-01-01

135

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

2012-01-20

136

Organic intermediates in the anaerobic biodegradation of coal to methane under laboratory conditions  

USGS Publications Warehouse

Organic intermediates in coal fluids produced by anaerobic biodegradation of geopolymers in coal play a key role in the production of methane in natural gas reservoirs. Laboratory biodegradation experiments on sub-bituminous coal from Texas, USA, were conducted using bioreactors to examine the organic intermediates relevant to methane production. Production of methane in the bioreactors was linked to acetate accumulation in bioreactor fluid. Long chain fatty acids, alkanes (C19-C36) and various low molecular weight aromatics, including phenols, also accumulated in the bioreactor fluid and appear to be the primary intermediates in the biodegradation pathway from coal-derived geopolymers to acetate and methane. ?? 2010.

Orem, W.H.; Voytek, M.A.; Jones, E.J.; Lerch, H.E.; Bates, A.L.; Corum, M.D.; Warwick, P.D.; Clark, A.C.

2010-01-01

137

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

NASA Technical Reports Server (NTRS)

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

Steffes, Paul G.

1989-01-01

138

Influence of material properties and laboratory test conditions on SOHIC at line pipe carbon steels  

SciTech Connect

Stress oriented hydrogen induced cracking (SOHIC) is a cracking mechanism typical for of low strength line pipe carbon steels. The paper reports on investigations to find experimental conditions suitable to study medium and materials related parameters influencing the SOHIC susceptibility of steel. It was not possible to identify medium conditions that produce SOHIC at stressed, unnotched samples under 1 bar (0.1 MPa) hydrogen sulfide. Increasing the test severity by filming 4-point bend or tensile specimens with a low concentrated aqueous salt solution instead of submerging them in this solution yielded appropriate SOHIC test conditions, the severity of which can be easily modified with the H{sub 2}S partial pressure. It was exemplified that the concentration of nonmetallic inclusions, cold deformation (e.g. specimens preparation by flattening of curved coupons) and banded microstructures significantly contribute to the SOHIC susceptibility. Uniaxial tensile testing can evaluate critical stress levels for SOHIC development under given hydrogen sulfide partial pressures.

Siegmund, G.; Bruckhoff, W. [BEB Erdgas und Erdol GmbH, Hannover (Germany); Schmitt, G.; Pankoke, U.; Sadlowsky, B. [Iserlohn Univ. of Applied Sciences (Germany). Lab. for Corrosion Protection

1998-12-31

139

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 1.8·10(-3) to 8.2·10(-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-García, N; Zafra-Gómez, A; Navalón, A; González-López, J; Hontoria, E; Vílchez, J L

2013-05-15

140

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

NASA Astrophysics Data System (ADS)

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 laboratory incubation study over 18 months to monitor total litter dry mass, carbon, nitrogen, and Hg mass and concentrations, and the respective stochiometric ratios, of 100 well characterized litter samples. Fresh surface litter samples (~ 30 g) of four different forest types (mixed deciduous, aspen, pine, and blue Oak) were incubated in acid-cleaned glass jars covered by Teflon filters to allow gas exchange while avoiding particulate and dust deposition. Litter samples were kept at 25 degree celcius in the dark and kept moist by occasional addition of Hg free water. Samples were also extracted for soluble Hg to assess how decomposition may affect aqueous-phase Hg mobility. Additional litter samples were placed in the field to compare laboratory results to in situ field decomposition. Initial results after six months of decomposition show that dry mass of the four litter types decreased by 2-8% after 3 months and 3-11% after 6 months as compared to initial dry mass. Total Hg mass showed inconsistent patterns after 3 months (+3% to -6% mass change), but started to show consistent decreases (from 2 to 16%) after 6 months of incubation. Total amounts of soluble Hg extracted from litter samples showed decreasing solubility of Hg with increasing duration of incubation. Hence, our results show that dry mass and C losses during decomposition (through losses of CO2) did not lead to equal losses of atmospheric Hg during initial stages of decomposition, but that some losses of Hg are becoming visible after six months, albeit strongly dependent on litter types. Decomposition of surface litter may hence be source of Hg to the atmosphere, thereby recycling atmospheric mercury previously fixed by leaves and deposited by litterfall.

Pokharel, A. K.; Obrist, D.

2009-12-01

141

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

PubMed

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

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

2014-01-01

142

Effect of population density on reproduction in Microtus fortis under laboratory conditions.  

PubMed

Between December 2011 and March 2012, the reproductive characteristics of Microtus fortis reared in the laboratory at different population densities were assessed. In all, 258 male and female voles were randomly divided into 4 groups and reared at densities of 2, 4, 6, and 8 animals per cage (sex ratio: 1:1). The results showed that the pregnancy rate (?2 = 21.671, df = 3, P < 0.001) and first farrowing interval (F = 12.355, df = 3, P < 0.001) were significantly different among the different population density groups, but the mean litter size (mean ± SD) was not (F = 2.669, df = 3, P > 0.05). In particular, the reproductive index and sex hormone levels showed a significant difference among the different density groups studied. PMID:24873906

Han, Qunhua; Zhang, Meiwen; Guo, Cong; Shen, Guo; Wang, Yong; Li, Bo; Xu, Zhenggang

2014-06-01

143

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

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

144

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

145

Laboratory measurements of the 7.5-9.38-mm absorption of gaseous ammonia (NH3) under simulated Jovian conditions  

NASA Technical Reports Server (NTRS)

An attempt is made to infer the abundance and distribution of ammonia from RF emission measurements more accurately than heretofore, on the basis of the results of laboratory measurements for the mm-wave opacity of gaseous ammonia under simulated Jovian atmosphere conditions. The measurements were conducted at various frequencies in the 32-40 GHz range at 2 atm and 203 K; the atmospheric mixture was 88.34 percent H2, 9.81 percent He, and 1.85 percent NH3. Experimental results are found to be readily modeled by the Gross (1955) line-shape factor, rather than that of Van Vleck and Weisskopf (1945).

Joiner, Joanna; Steffes, Paul G.; Jenkins, Jon M.

1989-01-01

146

Nitrogen storage and remobilization in ash ( Fraxinus excelsior ) under field and laboratory conditions  

Microsoft Academic Search

Storage and remobilization of nitrogen (N) were studied in ash trees (Fraxinus excelsior) under both field and greenhouse conditions. Experiments in the greenhouse providing 15N labelled fertilizer to the trees showed that the major quantity of N remobilized during subsequent spring was from the roots,\\u000a and only a small amount from the stem. This corresponded with a loss of soluble

Peter Marmann; Renate Wendler; Peter Millard; H. Heilmeier

1997-01-01

147

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

NASA Technical Reports Server (NTRS)

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 atmospheric model.

Steffes, P. G.

1984-01-01

148

Role of drainage conditions in deformation and fracture of porous rocks under triaxial compression in the laboratory  

NASA Astrophysics Data System (ADS)

In order to investigate the role of drainage conditions in deformation and fracture behaviors of porous rocks, the authors carried out a series of rock fracture tests under triaxial compression in the laboratory. The detailed space-time distribution of acoustic emission due to microcracking was used to examine pre-failure damage and failure behavior in Berea sandstone, which has a porosity of ?20% and a permeability of ?100 mD. The pore pressures or flow rates at the ends of the test sample were precisely controlled to simulate different drainage conditions. Experimental results indicate that drainage conditions play a governing role in deformation and fracture. The well-established dilatancy-hardening effect can be greatly suppressed by dilatancy-driven fluid flowing under good drainage conditions. Fast diffusion of pore pressure leads to a significant reduction in rock strength and stabilization of the dynamic rupture process. Furthermore, good drainage conditions have the potential to enlarge the nucleation dimension and duration, thereby improving the predictability of the final catastrophic failure. In addition, compaction bands, which were observed in porous rocks under higher confining pressure, were also observed at low confining pressure (corresponding to a depth of ?1 km) in undrained tests. These results are particularly important for research fields in which fluid migration or pore pressure diffusion is expected to play a role, such as hydrocarbon reservoirs, enhanced geothermal systems, geological storage of CO2.

Lei, Xinglin; Tamagawa, Tetsuya; Tezuka, Kazuhiko; Takahashi, Manabu

2011-12-01

149

Functional response analysis of Anisops sardea (Hemiptera: Notonectidae) against Culex quinquefasciatus in laboratory condition  

PubMed Central

Background & objectives: Culex quinquefasciatus is the principal vector of lymphatic filariasis (LF). Application of alternative vector control methodologies are aimed at reduction of mosquito breeding sites and biting activity through the use of biological control methods. In the present study, functional response of aquatic Hemipteran backswimmer, Anisops sardea was assessed against Cx. quinquefasciatus larvae in laboratory bioassay. Methods: The functional respons of A. sardea was assessed against IIIrd instar larvae of Cx. quinquefasciatus. Respective handling times and coefficient of attack rates were determined by a non linear polynomeal regression equation. Results: The results of rates of predation in variable prey densities exhibited a ‘linear rise to plateau curve’, associated with ‘Type -II’ functional response. The logistic regression estimated a significant negative linear parameter (P1<0) which also supported the same observation. Associated ‘attack rates’ and ‘handling times’ were also calculated using the Holling Disc Equation. Interpretation & conclusions: The results of present experiments indicate that A. sardea can be used as a biocontrol agent against the larval forms of Cx. quinquefasciatus in temporarily available breeding places of mosquito with relatively clear water. However, a detailed field study has to be done to confirm these findings. PMID:25488451

Mondal, Rajendra Prasad; Ghosh, Anupam; Bandyopadhyay, Subhasis; Chandra, Goutam

2014-01-01

150

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

151

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

USGS Publications Warehouse

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

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

1988-01-01

152

Soil mercury and CO2 emissions and their relationship under controlled laboratory conditions: Effects of oxygen depletion and soil sterilization  

NASA Astrophysics Data System (ADS)

Terrestrial carbon (C) pools play an important role in uptake, deposition, sequestration, and emission of atmospheric mercury (Hg). Thus, we investigated the fate of Hg during C mineralization processes using a laboratory flux set-up to evaluate to what degree decomposition of organic matter leads to emission and re- emission of Hg to the atmosphere, increased mobilization within terrestrial ecosystems, or long-term sequestration. Our laboratory system was supplied by air from pressurized tanks and allowed concurrent measurements of Hg and CO2 fluxes from 6 replicate soils chambers under controlled environmental conditions. Experimental treatments of flux samples included manipulations of C mineralization rates (by means of O2 depletion, sterilization, etc.). Results showed an excellent control on soil fluxes and highly accurate and replicable measurements of soil Hg and CO2 (i.e., mineralization) fluxes and little direct relationships between soil mineralization and Hg emission rates. Surprisingly though, soil Hg emissions increased in soils under anaerobic conditions (depletion of O2) indicating that low soil redox potential and/or anaerobic microbes might enhance Hg emission from terrestrial soils.

Berger, C.; Fain, X.; Obrist, D.

2008-12-01

153

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

PubMed Central

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

Harrison, F L; Lam, J R

1986-01-01

154

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

155

Laboratory simulations of the interaction between ozone and chloroacetic acids in the conditions close to stratospheric  

NASA Astrophysics Data System (ADS)

The interaction between ozone and mono-, di-, and trichloroacetic acids are studied using a flow vacuum gas discharge setup in a regime close to stratospheric conditions (in the temperature range of 77 to 250 K, at pressures of 10-3 to 0 Torr, and in the presence of ice). The interaction between ozone and trichloroacetic acid starts at 77 K, while interaction with monochloroacetic acid begins when the temperature is raised to 200 K. The reactions are assumed to proceed via different mechanisms: chlorine oxides of different composition are the reaction products, as is shown using low-temperature IR spectroscopy. Preliminary adsorption of the acids on a surface of ice raises the temperature of interaction to 190 K.

Strokova, N. E.; Savilov, S. V.; Morozov, I. I.; Yagodovskaya, T. V.; Lunin, V. V.

2015-01-01

156

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

SciTech Connect

The National Electrostatics Corporation's (NEC) Toroidal Volume Ion Source (TORVIS) source is known for exceptionally high proton currents with minimal service downtime as compared to traditional sputter sources. It has been possible to obtain over 150{mu}A of proton current from the source, with over 70{mu}A on the target stage. However, beam fluxes above {approx}1 Multiplication-Sign 10{sup 17}/m2-s may have many undesirable effects, especially for insulators. This may include high temperature gradients at the surface, sputtering, surface discharge, cracking or even disintegration of the sample. A series of experiments were conducted to examine the role of high current fluxes in a suite of ceramics and insulating materials. Results will show the optimal proton irradiation conditions and target mounting strategies needed to minimize unwanted macro-scale damage, while developing a procedure for conducting preliminary radiation experiments.

Wetteland, C. J.; Field, K. G.; Gerczak, T. J. [Materials Science Program, University of Wisconsin, Madison, WI 53706 (United States); Eiden, T. J.; Maier, B. R.; Albakri, O.; Sridharan, K.; Allen, T. R. [Department of Engineering Physics, University of Wisconsin, Madison, WI 53706 (United States)

2013-04-19

157

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

PubMed

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

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

2009-12-01

158

Effects of two biorational insecticides, spinosad and methoxyfenozide, on Spodoptera littoralis (Lepidoptera: Noctuidae) under laboratory conditions.  

PubMed

The toxicity of two biorational insecticides, spinosad (Tracer) and methoxyfenozide (RH-2485), was tested against eggs, larvae, and pupae of the noctuid Spodoptera littoralis (Boisduval). In the first experiment, filter paper circles containing egg masses of two different age classes, young (<24 h old) and old (24-48 h old), were dipped in different concentrations of each insecticide diluted in either water or acetone. No ovicidal activity was recorded when insecticides were diluted in water. In contrast, when insecticides were diluted in acetone, both egg age classes generally showed a concentration-dependent response for both compounds. Mortality of larvae that hatched from both egg age classes was significantly increased, compared with control larvae, at all concentrations of both insecticides when diluted in water or acetone alike. The prevalence of mortality was similar with each insecticide. In the second experiment, third instars of S. littoralis were fed semisynthetic diet containing different concentrations of both insecticides. According to LC50 values, no significant differences were observed between spinosad (2.11 mg [AI]/kg diet) and methoxyfenozide (3.98 mg [AI]/kg diet) after 48 h of treatment, based on the overlap of 95% CL. Toxic effects on the mortality of pupae, adult emergence, and the prevalence of deformed adults after topical application on young pupae also were examined. Only methoxyfenozide caused pupal mortality and deformed adults. Our results suggest that spinosad and methoxyfenozide are potentially potent compounds for control of S. littoralis. PMID:15666743

Pineda, Samuel; Budia, Flor; Schneider, Marcela Inés; Gobbi, Antonio; Viñuela, Elisa; Valle, Javier; Del Estal, Pedro

2004-12-01

159

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

160

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

161

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

PubMed

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

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

2002-06-01

162

Impacts of Bt rice expressing Cry1C or Cry2A protein on the performance of nontarget leafhopper, Nephotettix cincticeps (Hemiptera: Cicadellidae), under laboratory and field conditions.  

PubMed

Transgenic rice expressing Bacillus thuringiensis Berliner (Bt) protein can effectively control target insects including stem borers and leaf folders. However, the potential effects of Bt rice on nontarget organisms including nontarget herbivores have not been fully evaluated. In the current study, ecological fitness parameters of the nontarget herbivore, Nephotettix cincticeps (Uhler) (Hemiptera: Cicadellidae), fed on T1C-19 (Cry1C) or T2A-1 (Cry2A) rice were compared with non-Bt rice (MH63) under laboratory conditions. A 2-yr field trial was also conducted to monitor the population dynamics of N. cincticeps in the Bt and control rice plots using the vacuum-suction machine and yellow sticky card traps. Laboratory results showed that there were no significant differences in some of biological parameters including egg developmental duration, adult fresh weight, adult longevity, and oviposition period when N. cincticeps fed on Bt or non-Bt rice was compared. However, the survival rate of N. cincticeps nymphs fed on T2A-1 Bt rice plants was significantly higher than that on the control. When N. cincticeps fed on T1C-19 Bt rice plants, its nymphal duration was significantly longer and fecundity significantly lower compared with those fed on both T2A-1 Bt and non-Bt rice plants; the preoviposition period of N. cincticeps fed on T1C-19 and T2A-1 Bt rice was also significantly shorter than those on non-Bt rice. Nonetheless, both seasonal density and population dynamics of N. cincticeps adults and nymphs were similar between Bt (T1C-19 and T2A-1) and non-Bt rice plots under field conditions. In conclusion, our results indicate that our two tested Bt rice lines would not lead to higher population of N. cincticeps. Long-term experiments to monitor the population dynamics of N. cincticeps at large scale need to be carried out to confirm the current results. PMID:24472210

Lu, Z B; Tian, J C; Wang, W; Xu, H X; Hu, C; Guo, Y Y; Peng, Y F; Ye, G Y

2014-02-01

163

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

PubMed

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

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

2014-03-01

164

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

PubMed Central

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

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

2012-01-01

165

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

PubMed Central

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

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

2012-01-01

166

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

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and...Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests, and...diagnostic tests. All diagnostic x-ray tests, diagnostic laboratory...

2013-10-01

167

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

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and...Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests, and...diagnostic tests. All diagnostic x-ray tests, diagnostic laboratory...

2014-10-01

168

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

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and...Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests, and...diagnostic tests. All diagnostic x-ray tests, diagnostic laboratory...

2011-10-01

169

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, and...Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests, and...diagnostic tests. All diagnostic x-ray tests, diagnostic laboratory...

2010-10-01

170

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

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and...Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests, and...diagnostic tests. All diagnostic x-ray tests, diagnostic laboratory...

2012-10-01

171

Similar names for similar biologics.  

PubMed

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

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

2014-10-01

172

Comparison of longevity between a laboratory strain and a natural population of Anastrepha Fraterculus (Diptera: Tephritidae) under field cage conditions  

SciTech Connect

The South American fruit fly Anastrepha fraterculus (Wiedemann) is one of the most destructive fruit pests in this region, infesting major fruit crops. Implementation of the sterile insect technique (SIT) as part of an area-wide integrated approach against this species requires information on the survival of mass-reared and sterilized insects in the field and their ability to mate with wild females. The survival rates in field cages of both non-irradiated and irradiated laboratory flies were compared with that of wild flies. Both types of laboratory flies survived longer than their wild counterparts over the 8 days under the experimental conditions. The irradiation dose (70 Gy) did not affect survival of the laboratory reared flies. Our results improve the prospect of integrating the SIT into the control of A. fraterculus populations in Argentina. (author) [Spanish] Anastrepha fraterculus (Wiedemann), la mosca sudamericana de la fruta, es una de las plagas mas destructivas en la region que infesta a los principales cultivos de frutas. La implementacion de la Tecnica del Insecto Esteril (TIE) como parte de un manejo integrado en areas extensivas contra esta especie requiere ensayos que demuestren que los insectos producidos en forma masiva y esterilizados son capaces de sobrevivir en el campo y aparearse con las hembras silvestres. Se comparo la supervivencia de individuos de una linea de laboratorio, tanto irradiados como no irradiados con la de individuos de una poblacion natural. Los dos tratamientos de moscas de laboratorio sobrevivieron mas tiempo que las salvajes durante los 8 dias y en las condiciones ensayadas. La dosis de radiacion (70 Gy.) no afecto la supervivencia de las moscas criadas en laboratorio. Nuestros resultados mejoran las perspectivas de integrar la TIE en el control de las poblaciones argentinas de A. fraterculus. (author)

Gomez Cendra, P.; Vilardi, J. [Depto. Ecologia, Genetica y Evolucion, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, (1428) Buenos Aires (Argentina); Segura, D.; Cladera, J. [Instituto de Genetica, INTA Castelar, CC25, (1712), Buenos Aires (Argentina); Allinghi, A. [Comision Nacional de Energia Atomica, CNEA, Buenos Aires (Argentina)

2007-03-15

173

Clinician Perspectives about Molecular Genetic Testing for Heritable Conditions and Development of a Clinician-Friendly Laboratory Report  

PubMed Central

The use of molecular genetic tests for heritable conditions is expected to increase in medical settings, where genetic knowledge is often limited. As part of a project to improve the clarity of genetic test result reports to minimize misunderstandings that could compromise patient care, we sought input about format and content from practicing primary care clinicians. In facilitated workgroup discussions, clinicians from pediatric, obstetrics-gynecology, and family practice provided their perspectives about molecular genetic testing with a focus on the laboratory reporting of test results. Common principles for enhancing the readability and comprehension of test result reports were derived from these discussions. These principles address the presentation of patient- and test-specific information, the test result interpretation, and guidance for future steps. Model test result reports for DNA-based cystic fibrosis testing are presented that were developed based on workgroup discussions, previous studies, and professional guidelines. The format of these model test reports, which are applicable to a variety of molecular genetic tests, should be useful for communicating essential information from the laboratory to health care professionals. PMID:19197001

Lubin, Ira M.; McGovern, Margaret M.; Gibson, Zoe; Gross, Susan J.; Lyon, Elaine; Pagon, Roberta A.; Pratt, Victoria M.; Rashid, Jamila; Shaw, Colleen; Stoddard, Lander; Trotter, Tracy L.; Williams, Marc S.; Amos Wilson, Jean; Pass, Kenneth

2009-01-01

174

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

PubMed

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

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

2005-01-01

175

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

176

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

177

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

2013-02-01

178

Effects of greenhouse pesticides on the soil-dwelling predatory mite Stratiolaelaps scimitus (Acari: Mesostigmata: Laelapidae) under laboratory conditions.  

PubMed

Knowledge of the effects of pesticides on biological control agents is required for the successful implementation of integrated pest management (IPM) programs in greenhouse production systems. Laboratory assays were conducted to assess the effects of an acaricide (dicofol), two insecticides (chlorpyrifos and pyriproxyfen), and two fungicides (fosetyl-Al and mefenoxam) on Stratiolaelaps scimitus (Womersley), a soil-dwelling predatory mite widely marketed in North America under the name Hypoaspis miles (Berlese) as a biological control agent of dark-winged fungus gnats (Bradysia spp.). Eggs, larvae, protonymphs, deutonymphs, and adult male and female mites were first assayed using dicofol, an acaricide used in the experiments as a positive control, applied to filter paper in an enclosed arena. Protonymphs were assayed for lethal and sublethal effects against the remaining pesticides at maximum label-recommended rates applied to filter paper, by using dicofol as a positive control and water as a negative control. The larva and protonymph were the life stages most susceptible to dicofol, with estimated 24-h LC50 values of 9 and 26 mg m(-2), respectively. Chlorpyrifos was highly toxic to the protonymphs of S. scimitus, causing >95% mortality after 24-h exposure and 100% mortality after 48 h. In contrast, the insect growth regulator (IGR) pyriproxyfen was much less toxic to protonymphs of S. scimitus; pyriproxyfen caused no significant mortality, compared with <5% mortality in the water control. Mortality caused by the fungicides was also relatively low; 72-h exposure to fosetyl-Al and mefenoxam resulted in 17.4 and 27.5% mortality, respectively. The IGR and fungicides increased the duration of the protonymphal stage by 1.2-1.8-fold, but they had no effect on the duration of subsequent life stages, nor on the duration of preoviposition, oviposition, and postoviposition periods of adult females. Total numbers and viability of eggs laid by mites exposed to the IGR and fungicides did not differ from the negative control, although the average rate of egg production during the oviposition of mites exposed to fosetyl-Al was increased. Pyriproxyfen, fosetyl-Al, and mefenoxam are likely to be compatible with S. scimitus under field conditions, because these pesticides caused little mortality of protonymphs, and they did not negatively affect the development and reproduction of S. scimitus under extreme laboratory conditions. In contrast, the use of chlorpyrifos in conjunction with S. scimitus is not recommended unless more comprehensive testing under semifield or field conditions demonstrates compatibility. PMID:15279255

Cabrera, Ana R; Cloyd, Raymond A; Zaborski, Edmond R

2004-06-01

179

Conditions?  

Microsoft Academic Search

Research interests in feral hogs typically involve their negative impacts on ecosystems or their potential as a disease reservoir, especially with disease transmission to domestic swine. Authors within scientific literature state that feral hogs were captured as part of their research, but usually fail to mention specific conditions in which hogs were captured. Novice researchers of feral hogs must rely

A. Christy Wyckoff; Scott E. Henke; Kurt C. VerCauteren

180

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

181

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

PubMed Central

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

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

2013-01-01

182

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

SciTech Connect

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

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

2013-08-15

183

The residual life of bendiocarb on different substrates under laboratory and field conditions in Benin, Western Africa  

PubMed Central

Background The efficacy of bendiocarb against pyrethroid resistant An. gambiae and the residual life of this insecticide on different substrates were evaluated under laboratory and field conditions. Methods Bioassays according to the WHO (World Health Organization) standard protocol were carried out on different substrates impregnated with bendiocarb. Data were analyzed using a binomial regression model with R software. Results A good efficacy of the bendiocarb against pyrethroid resistant An. gambiae and a high variation of its residual life according to the surfaces treated was observed. The probability that a female mosquito died after exposure to a treated substrate was below 80% after 13 weeks for the teak wood; 7 weeks for the wall made with a mixture of sand and cement and 6 weeks for walls made with red clay and those made with a mixture of the red clay and cement. Conclusions Considering the residual life of bendiocarb on walls made with red clay, the main substrates treated during IRS campaigns in rural areas in Benin, more than 2 treatments rounds per year would be necessary to achieve a long term efficacy of IRS using bendiocarb in these areas. Financial and logistical resources required to achieve such levels of coverage need more political will from leaders of African endemic countries. While waiting for innovative malaria control tool, alternative insecticides or combinations of insecticides have to be used for insecticide resistance management in Benin. PMID:24220151

2013-01-01

184

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

USGS Publications Warehouse

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

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

2011-01-01

185

Triboelectric Charging of Fine Particles: Understanding Sample Transport Under Simulated Martian Conditions for the Mars Science Laboratory  

NASA Astrophysics Data System (ADS)

We report on the nature of fine particle (lees than 150 micron) transport under simulated Martian conditions, in order to better understand the Mars Science Laboratory's sample acquisition, processing and handling subsystem (SA/SPaH). We find that triboelectric charging due to particle movement may have to be controlled in order for successful transport of fines that are created within the drill, processed through the sample handing system (CHIMERA), and delivered to the SAM and CheMin instruments. These fines will be transferred to the portioner, a 3 mm diameter, 8 mm deep distribution center where they will drop ~ 2 cm to the instrument inlet funnels. In our experiments, charging of the simulant (Mars Mojave Simulant - MMS) resulted in 1.5 to 3 nanocoulombs of charge for a 3g aliquot. Due to electrostatics, this process may result in clumping or charge repulsion of fines, which can result in particle sorting. Both of these results can potentially result in an inaccurate sample analysis for the onboard instruments.

Anderson, R. C.; Peters, G. H.; Beegle, L. W.; Manatt, K. S.; Fleming, G.; Sollitt, L.

2008-12-01

186

Insecticidal activity of cerrado plant extracts on Rhodnius milesi Carcavallo, Rocha, Galvão & Jurberg (Hemiptera: Reduviidae), under laboratory conditions.  

PubMed

Chagas' disease is chiefly transmitted by feces of haematophagous bugs (Triatominae) that ingested Trypanosoma cruzi from blood of infected people or animals. Pyrethroids have been the main insecticides used against these insects. However, some populations of insects have shown significant levels of resistance to several pyrethroids, indicating the need of new insecticides for the control of triatomines. Insecticidal activity of 24 Cerrado plant extracts belonging to five species of four families were assayed on fourth instar nymphs of Rhodnius milesi Carcavallo, Rocha, Galvão & Jurberg (Hemiptera: Reduviidae), under laboratory conditions. For the extract application on triatomines, 50 microg of the extract were topically applied in duplicate on dorsal tergites of ten insects. Insects topically treated with acetone, ethanol, as well as insects with no treatment were used as controls. Triatomines were observed over a 28-day period. Hexanic and ethanolic extracts of Simarouba versicolor, Guarea kunthiana, Guarea guidonia and Talauma ovata caused mortality between 20% and 95% of R. milesi in comparison with the controls, which showed no insect mortality. These preliminary data suggest that the ethanolic extract of the root bark of S. versicolor and the hexanic extract of the root of G. guidonia, responsible for a 95% and 75% insect mortality, respectively, should be chemically investigated and monitored through biological assays in order to determine their insecticidal components, that could be used as a molecular model or as biorational compounds for use in insect control programmes. PMID:17352079

Coelho, André A M; de Paula, José E; Espíndola, Laila S

2006-01-01

187

YUCCA Mountain Project - Argonne National Laboratory, Annual Progress Report, FY 1997 for activity WP 1221 unsaturated drip condition testing of spent fuel and unsaturated dissolution tests of glass.  

SciTech Connect

This document reports on the work done by the Nuclear Waste Management Section of the Chemical Technology Division of Argonne National Laboratory in the period of October 1996 through September 1997. Studies have been performed to evaluate the behavior of nuclear waste glass and spent fuel samples under the unsaturated conditions (low-volume water contact) that are likely to exist in the Yucca Mountain environment being considered as a potential site for a high-level waste repository. Tests with actinide-doped waste glasses, in progress for over 11 years, indicate that the transuranic element release is dominated by colloids that continuously form and span from the glass surface. The nature of the colloids that form in the glass and spent fuel testing programs is being investigated by dynamic light scattering to determine the size distribution, by autoradiography to determine the chemistry, and by zeta potential to measure the electrical properties of the colloids. Tests with UO{sub 2} have been ongoing for 12 years. They show that the oxidation of UO{sub 2} occurs rapidly, and the resulting paragenetic sequence of secondary phases forming on the sample surface is similar to that observed for uranium found in natural oxidizing environments. The reaction of spent fuel samples in conditions similar to those used with UO{sub 2} have been in progress for over six years, and the results suggest that spent fuel forms many of the same alteration products as UO{sub 2}. With spent fuel, the bulk of the reaction occurs via a through-grain reaction process, although grain boundary attack is sufficient to have reacted all of the grain boundary regions in the samples. New test methods are under development to evaluate the behavior of spent fuel samples with intact cladding: the rate at which alteration and radionuclide release occurs when water penetrates fuel sections and whether the reaction causes the cladding to split. Alteration phases have been formed on fine grains of UO{sub 2} in contact with small volumes of water within a several month period when the radiolysis product H{sub 2}O{sub 2} is added to the groundwater solution. The test setup has been mocked up for operation with spent fuel in the hot-cell.

Bates, J. K.; Buck, E. C.; Emery, J. W.; Finch, R. J.; Finn, P. A.; Fortner, J.; Hoh, J. C.; Mertz, C.; Neimark, L. A.; Wolf, S. F.; Wronkiewicz, D. J.

1998-09-18

188

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

SciTech Connect

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

DUNCAM JB; GUTHRIE MD; LUECK KJ; AVILA M

2007-07-18

189

Gamma butyrolactone (GBL) and gamma valerolactone (GVL): similarities and differences in their effects on the acoustic startle reflex and the conditioned enhancement of startle in the rat.  

PubMed

Gamma butyrolactone (GBL) is metabolized to gamma hydroxybutyrate (GHB) in the body. GHB is a DEA Schedule 1 compound; GBL is a DEA List 1 chemical. Gamma valerolactone (GVL) is the 4-methyl analog of GBL; GVL is metabolized to 4-methyl-GHB; GVL is NOT metabolized to GBL or GHB. The effects of GBL (18.75-150 mg/kg), GVL (200-1600 mg/kg) or vehicle on the acoustic startle reflex (ASR), and the classically-conditioned enhancement of startle, the Startle Anticipated Potentiation of Startle (SAPS) response were studied in male rats. Both compounds produced a dose-dependent reduction of ASR, with GBL 5-7 times more potent than GVL. In contrast, GBL treatment significantly reduced SAPS at doses that exerted only moderate effects on ASR, whereas GVL exerted little or no effect on the SAPS, except at doses that produced pronounced reductions in Noise Alone ASR. In a second experiment, rats were tested for Noise Alone ASR behavior following treatment with a single mid-range dose of GBL (75 mg/kg), GVL (400mg/kg) or vehicle; immediately following startle testing the animals were sacrificed and their brains and blood were collected for determination of GHB, 4-methyl-GHB, GBL and GVL. GHB was found in measurable concentrations in all of the blood specimens and 6 (of 8) of the brain specimens from the GBL-treated subjects. 4-Methyl-GHB was found in measurable concentrations in all of the blood and brain specimens of the GVL-treated subjects; the change in startle amplitude was inversely correlated to the brain concentrations of these compounds. These findings confirm the differences in the metabolic fate of GBL and GVL as pro-drugs for the formation of GHB and 4-methyl-GHB, respectively. Moreover, the dissimilarity in effect profile for GBL and GVL on ASR versus SAPS behaviors suggests that different receptor(s) may be involved in mediating these behavioral effects. PMID:22349589

Marinetti, Laureen J; Leavell, Bonita J; Jones, Calleen M; Hepler, Bradford R; Isenschmid, Daniel S; Commissaris, Randall L

2012-06-01

190

Dynamic similarity in erosional processes  

USGS Publications Warehouse

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

Scheidegger, A.E.

1963-01-01

191

[Conditioning studies in the Pavlov's laboratory during 75 years of its existence (on the 150th birthday of Ivan Petrovich Pavlov)].  

PubMed

The paper reviews experimental and clinical data obtained on physiology and pathology of the higher nervous system by the Laboratory founded by I. P. Pavlov during 75 years of its existence: the principle of systemic organisation of the brain structures activity, the role of separate subcortical structures in organisation of behaviour, theoretical development of experimental pathology problems, inner inhibition, the role of sympathetic nervous system in conditioning, possible neurophysiological and neurochemical mechanisms of conditioning. PMID:10641258

Suvorov, N F; Vo?lokova, N L

1999-01-01

192

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

PubMed

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

Imoulan, Abdessamad; Elmeziane, Abdellatif

2014-03-01

193

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

194

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

PubMed Central

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

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

2013-01-01

195

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

NASA Astrophysics Data System (ADS)

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

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

2014-11-01

196

The effect of metals on condition and pathologies of European eel (Anguilla anguilla): in situ and laboratory experiments.  

PubMed

Forty-nine wild eels (Anguilla anguilla) caught in the Albufera Lake (Spain), measuring 24.0-75.0 cm in length and 25.0-637.7 g in weight, were examined for metals (Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb, Se and Zn), condition (CI and HSI indices), as well as for diseases (Anguillicola infestation; bacterial infections). Total metal load significantly increased in eel liver tissue parallel to total length and body weight (log), while silvering females (W(B) > 200 g; L ? 500 mm) exhibited the highest amounts of Co, Cu, Hg, Se and Zn. Diverse effects may be expected in these big eels due to long-term metal exposure. In fact, IMBI (individual mean (multi-metal) bioaccumulation index) and copper load (Ln) in particular, were significantly related with a decrease in the HSI, reflecting lower eel fitness. In addition, most silvering females (75%) showed a CI below 0.2, and this size group presented the highest prevalence of chronic diseases, at significant levels, that are non-lethal in the short term, but degenerative in the long term. Amounts of hepatic iron were not correlated with eel size; however, a significant, strong negative correlation between this metal (Ln) and HSI and CI was found for wild eels suffering from diseases of any aetiology. This also included small eels (W(B) <67 g; L < 350 mm), as this size group presented a significant prevalence of acute diseases caused by single virulent bacterial pathogens (i.e. Edwardsiella tarda and Vibrio vulnificus biotype 2). To assess the effect of metals on susceptibility to disease, yellow eels were maintained and exposed to iron, copper, and pathogens, in captivity under laboratory conditions. Co-exposure of eels to iron (9 ?g of Fe/g of fish) and bacterial pathogens by intraperitoneal injection (IP), yielded a hundred-fold reduction in the LD50 of all bacteria assayed (i.e. E. tarda, V. vulnificus, and motile Aeromonas), and also the time taken to cause eel death. Short-term aqueous exposure of eels to 0.4, 0.7, 1.7 and 3.9 ?M of copper, yielded increasing mortality among eels IP challenged by a single dose of 1.90 × 10(6) E. tarda cells, and this effect was significant for 1.7 ?M of copper. These results suggest a synergistic interaction among copper and iron, and bacterial disease agents, with respect to their effect on eel health, considering sublethal levels of metals that are currently found in natural waters. PMID:22030412

Esteve, Consuelo; Alcaide, Elena; Ureña, Rocio

2012-03-01

197

A review of hydrologic and geologic conditions related to the radioactive solid-waste burial grounds at Oak Ridge National Laboratory, Tennessee  

USGS Publications Warehouse

Solid waste contaminated by radioactive matter has been buried in the vicinity of Oak Ridge National Laboratory since 1944. By 1973, an estimated six million cubic feet of such material had been placed in six burial grounds in two valleys. The practice initially was thought of as a safe method for permanently removing these potentially hazardous substances from man's surroundings, but is now que.3tionable at this site because of known leaching of contaminants from the waste, transport in ground water, and release to the terrestrial and fluvial environments. This review attempts to bring together in a single document information from numerous published and unpublished sources regarding the past criteria used for selecting the Oak Ridge burial-ground sites, the historical development and conditions of these facilities as of 1974, the geologic framework of the Laboratory area and the movement of water and water-borne contaminants in that area, the effects of sorption and ion exchange upon radionuclide transport, and a description and evaluation of the existing monitoring system. It is intended to assist Atomic Energy Commission (now Energy Research and Development Administration) officials in the formulation of managerial decisions concerning the burial grounds and present monitoring methods. Sites for the first three burial grounds appear to have been chosen during and shortly after World War II on the basis of such factors as safety, security, and distance from sources of waste origin. By 1950, geologic criteria had been introduced, and in the latter part of that decade, geohydrologic criteria were considered. While no current criteria have been defined, it becomes evident from the historical record that the successful containment of radionuclides below land surface for long periods of time is dependent upon a complex interrelationship between many geologic, hydrologic, and geochemical controls, and any definition of criteria must include consideration of these factors. For the most part, the burial grounds have been developed by a simple cut and fill procedure similar to the operation of a municipal landfill. Low permeability of the residuum, high rainfall, shallow depth to ground water, the excavation of trenches below the water table, and other practices, have contributed to a condition of waste leaching in probably all of the burial grounds. Despite these conditions, only very small concentrations of radionuclides have been found in wells or otherwise attributed to the initial three, small sites in Bethel Valley. This fact, however, may be due in part to the scant extent of site monitoring of those burial grounds for transport of radionuclides in ground water, and to the discharge of liquid radioactive waste to the drainage in concentrations that probably would have masked the presence of contaminants derived from these burial grounds. In comparison to the Bethel Valley sites, larger amounts of radioactive contaminants have been found in wells, seeps, trench overflow, and the drainages that drain Burial Grounds 4 and 5 in Melton Valley. The movement of radionuclides from the trenches to the drainages show that the latter sites are not suitable for the retention of all contaminants under existing conditions, and invalidates the operational concept of long-term or permanent retention of all radionuclides in the geologic environment. The transport of many radioactive ions leached from the waste has been retarded by the very high sorptive and ion exchange capacity of the residuum with which the radionuclides have had contact. Not all radionuclides, though, will be retained in the subsurface by adsorption, absorption, or ion exchange. Among those radioactive contaminants that may be problematical with respect to trench burial at Oak Ridge are tritium and other negatively-charged nuclides, positively-charged radionuclides included in some of the complexed molecules, radioactive ions that have chemical properties si

Webster, D.A.

1976-01-01

198

Measurement of copper release rates from antifouling paint under laboratory and in situ conditions: implications for loading estimation to marine water bodies.  

PubMed

The release of biocides, such as copper (Cu), from antifouling (AF) coatings on vessel hulls represents a significant proportion of overall Cu loading in those harbors and estuaries where substantial numbers of small craft or large vessels are berthed. Copper release rates were measured on several self-polishing, tin-free coatings and an ablative Cu reference coating applied to steel panels using three measurement methods. The panels were exposed in natural seawater in San Diego Bay, and release rates were measured both in the laboratory and field over 2 years. Results with the static (20 cm x 30 cm) panels indicated that Cu release rates were initially high (25-65 microg Cu cm(-2)day(-1)), with a large range of values between paint types. Release rates declined to substantially lower rates (8-22 microg cm(-2)day(-1)) with reduced variability within 2 months. Release rates continued to decrease over time for approximately 6 months when relatively constant release rates were observed for most coatings. Over time, relative differences in Cu release rates measured by three exposure methods decreased, with all coatings exhibiting similar behavior toward the end of the study. Lowest overall Cu release rates were observed with the self-polishing experimental paint no. 7 in static-dynamic and in situ treatments. The highest periodic release rates were measured from panels that experienced periods of both static and dynamic exposure (8.7 ms(-1) rotation). The lowest release rates were measured from panels that experienced static, constant depth exposure, and where release rates were evaluated in situ, using a novel diver-deployed measurement system. Results from this in situ technique suggests that it more closely reflects actual Cu release rates on vessel hulls measured with intact natural biofilms under ambient conditions than measurements using standardized laboratory release rate methods. In situ measurements made directly on the AF surface of vessels demonstrated typically lower release rates than from the panel studies, averaging 8.2 microg cm(-2)day(-1) on pleasure craft, and 3.8 microg cm(-2)day(-1) on Navy vessels. The data suggest that the presence of an established biofilm likely serves to moderate the release of Cu from field-exposed antifouling coatings both on panels and hull surfaces. PMID:12787585

Valkirs, Aldis O; Seligman, Peter F; Haslbeck, Elizabeth; Caso, Joaquin S

2003-06-01

199

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

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

2013-07-01

200

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

Code of Federal Regulations, 2014 CFR

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

2014-07-01

201

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

Code of Federal Regulations, 2012 CFR

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

2012-07-01

202

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

Code of Federal Regulations, 2011 CFR

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

2011-07-01

203

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

Microsoft Academic Search

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

R. Rajendran; R. S. Prasad

1992-01-01

204

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

PubMed

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

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

2014-03-01

205

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...

206

Flue gas conditioning for improved particle collection in electrostatic precipitators. First topical report, Results of laboratory screening of additives  

SciTech Connect

Several tasks have been completed in a program to evaluate additives to improve fine particle collection in electrostatic precipitators. Screening tests and laboratory evaluations of additives are summarized in this report. Over 20 additives were evaluated; four were found to improve flyash precipitation rates. The Insitec particle analyzer was also evaluated; test results show that the analyzer will provide accurate sizing and counting information for particles in the size range of {le} 10 {mu}m dia.

Durham, M.D.

1993-04-16

207

Effects of ultraviolet radiation on early larval stages of the Alpine newt, Triturus alpestris , under natural and laboratory conditions  

Microsoft Academic Search

Although Alpine newts (Triturus alpestris) are found at altitudes up to 2500 m, their larvae proved to be extremely sensitive to UV radiation when exposed in clear\\u000a tapwater to natural sunlight or to comparable artificial UV-B radiation in the laboratory. The experiments revealed severe\\u000a skin damages (lysis of epithelial cells) and mortality after a few days of exposure. In their

Alexander M. Nagl; Rudolf Hofer

1997-01-01

208

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

...Uses G Appendix G to Subpart A of Part 82 Protection of Environment ENVIRONMENTAL... Production and Consumption Controls Pt. 82, Subpt. A, App. G Appendix G to Subpart A of Part 82—UNEP Recommendations for Conditions...

2010-07-01

209

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

210

ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE  

SciTech Connect

The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability of the new generator. The thermal vacuum test chamber is the first of its kind capable of testing a fueled power system to temperature that accurately simulate space. This paper outlines the new test and set up capabilities at the INL.

J. C. Giglio; A. A. Jackson

2012-03-01

211

Composed Computational Verb Similarities  

Microsoft Academic Search

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

Tao Yang

2009-01-01

212

Effect of water deficit on microbial characteristics in soil amended with sewage sludge or inorganic fertilizer under laboratory conditions.  

PubMed

The potential impact of different types of organic (sewage sludge) or inorganic (mineral fertilizer) amendments to a basic soil was investigated under dry conditions. A soil incubation experiment was carried out over 64 days; there were two fertility treatments: sewage sludge (SS) (140 t ha(-1)), mineral fertilizer (M) and an unamended control (C). Two levels of irrigation were imposed: (1) well-watered, kept at 60% of its water holding capacity, and (2) water-deficit at 6%. Available N-NO3-, N-NH4+ and P, and electrical conductivity (EC) increased in SS and M-treated soils. Under well-watered conditions activities of some enzymes (protease-BAA, phosphatase and beta-glucosidase), and microbiological properties (microbial biomass carbon, basal respiration and dehydrogenase activity) were stimulated in SS-treated soils. Under water-deficit conditions, protease-BAA, phosphatase and beta-glucosidase activities, and basal respiration were more reduced in SS than in C and M. Results showed that under severe dry conditions, soil microbial activity always remained higher in organic amended soils than when mineral fertilizer was added. PMID:16427275

Pascual, Inmaculada; Antolín, M Carmen; García, Carlos; Polo, Alfredo; Sánchez-Díaz, Manuel

2007-01-01

213

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

NASA Astrophysics Data System (ADS)

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

Kwak, Jihyun; Lee, Sunyoup; Lee, Seokhwan

2014-11-01

214

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

215

Similar Triangle Proof Theorems  

NSDL National Science Digital Library

This lesson will teach you three theorems that are used to prove two triangles similar to each other. Now that you understand similarity, you need some additional tools (or theorems) to PROVE that two triangles are similar to each other. Take notes on the following lesson: Similar Triangle Proof Notes Here is an interactive site that will help to solidify your understanding of proving triangles similar: Similar Triangle Proofs Class Zone Activity Here are some "real life" applications of these ...

Mrs. Neubert

2011-01-01

216

Plastic repair of the deferent duct with a silicone tubular prosthesis under conditions of a chronic experiment on laboratory animals  

Microsoft Academic Search

A connective tissue capsule consisting of a thin layer of the connective tissue envelopes the prosthesis by the end of week\\u000a 1 after replacement of a part of the deferent duct with a silicone tubular prosthesis under conditions of a chronic experiment.\\u000a By days 17–20 postoperation, two layers are clearly differentiated in the capsule: the outer layer consisted of a

A. A. Artyukhin

2007-01-01

217

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 methane’s 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

218

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

219

Effect of density on larval development and female productivity of Tisbe holothuriae (Copepoda, Harpacticoida) under laboratory conditions  

NASA Astrophysics Data System (ADS)

The harpacticoid copepod Tisbe holothuriae has been cultivated in the Helgoland laboratory for more than 20 years. The effects of density on the larval development and the female productivity were studied by comparing two culture systems: (1) enclosed system, and (2) running-water system. In both systems, a nutritious mixed diet of Dunaliella tertiolecta, Skeletonema costatum, and granulated Mytilus edulis was offered. Larval mortality, larval development and female productivity are found to be significantly dependent on both the population density and specificity of the culture system. Increasing density causes higher larval mortality, longer larval development time, and a reduction in female productivity. In comparison with the enclosed system, the running-water system shows decisive advantages: larval mortality is about 20% lower, the rate of larval development is about two days shorter, and there is a very high rate of nauplii production. The sex ratio exhibits high variations, but in general, there is no clear relationship between sex ratio and population density. Nevertheless, when reared in the running-water system, a relatively high percentage of females (>45%) was found at lower densities.

Zhang, Qian; Uhlig, G.

1993-06-01

220

Towards a Laboratory Determination of Microphysical Properties of H2O Ice Clouds Under Mars Atmospheric Conditions  

NASA Astrophysics Data System (ADS)

Recent observations by the Mars Global Surveyor (MGS) and Mars Odyssey (MO) suggest that water ice clouds have a fundamental role within the Mars climate system, which caused the Mars modeling community to include water ice clouds in global climate studies. However, simulation results depend strongly on cloud properties such as cloud particle size and number. These properties depend on the nucleation, which is dependent on the contact parameter, m, and the saturation ratio, S. As homogenous nucleation of most vapors requires very high levels of saturation, it is believed that heterogeneous nucleation is the most important microphysical process for water ice clouds in Martian atmospheric conditions. The proposed experiment will assess important cloud properties in order to improve models of both the current and past Martian hydrological cycles to be modeled. S, defined as the ratio of the partial vapor pressure to the equilibrium pressure, will be determined using IR spectrometry and pressure. This will allow m, the contact parameter between the water cluster and the simulated Mars dust, to be calculated. A contact parameter of m = 0.95 between the aerosol and water vapor has been assumed in some models. Typical values of m between liquid water and soil in terrestrial conditions range from m = 0.36 to 0.42. Water ice formed between 110 K and 150 K can either be amorphous or crystalline. These two phases of ice are spectrally distinct in the infrared, so the ice phase will be measured under these temperature conditions. The experimental design and parameters for six scenarios, representing the observed regional and seasonal where water ice cloud formation occurs, will be presented.

Reed, R. J.; Iraci, L. T.; Colaprete, A.

2006-12-01

221

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

222

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

NASA Technical Reports Server (NTRS)

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

Steffes, Paul G.; Jenkins, Jon M.

1987-01-01

223

The effect of conditioning rice during the laboratory milling process on the quality of the milled sample  

E-print Network

sample was conditioned by: (1) aerating with forced air maintained at seven different relative humidities, ranging from 0 to 100 percent; and (2) injecting liquid nitrogen through: (a) the mill roll only; and (b) both the mill roll and the rice sample.... There were significant increases in whole-kernel yields for all samples of both long- and medium-grain rice which were aerated during milling. However, the relative humidity of the air used had no significant effect on whole-kernel yields. This implied...

Childers, Roy Eugene

2012-06-07

224

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

PubMed

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

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

2014-04-01

225

Laboratory measurements of the microwave properties of H2S under simulated Jovian conditions with an application to Neptune  

NASA Technical Reports Server (NTRS)

H2S opacity may significantly affect the brightness temperatures of Uranus and Neptune due to possible depletion of ammonia in the tropospheres of those planets (de Pater et al. 1991). Though the rotational line centers of H2S are in the millimeter wavelengths region, significant absorption is also present at centimeter wavelengths due to pressure broadening of the lines. Accordingly, the properties of H2S under Jovian conditions have been measured in order to constrain further the constituents' abundances on these planets. These absorptivity measurements show values that are significantly greater than values predicted by the Van Vleck-Weisskopf models traditionally used at centimeter wavelengths. In order to better model the opacity due to H2S under Jovian conditions a Ben-Reuven lineshape formalism has therefore been developed and is presented. This formalism provides a possible constraint on the relative abundances of H2S and NH3 on Neptune based on Voyager 2 radio occultation results (Lindal 1992).

Deboer, David R.; Steffes, Paul G.

1994-01-01

226

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

PubMed

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

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

2013-03-01

227

Eta Carinae: An Astrophysical Laboratory to Study Conditions During the Transition Between a Pseudo-Supernova and a Supernova  

NASA Astrophysics Data System (ADS)

A major puzzle in the studies of supernovae is the pseudo-supernova, or the near-supernovae state. It has been found to precede, in timespans ranging from months to years, a number of recently-detected distant supernovae. One explanation of these systems is that a member of a massive binary underwent a near-supernova event shortly before the actual supernova phenomenon. Luckily, we have a nearby massive binary, Eta Carinae, that provides an astrophysical laboratory of a near-analog. The massive, highly-eccentric, colliding-wind binary star system survived a non-terminal stellar explosion in the 1800's, leaving behind the incredible bipolar, 10"x20" Homunculus nebula. Today, the interaction of the binary stellar winds 1") is resolvable by the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST). Using HST/STIS, several three-dimensional (3D) data cubes (2D spatial, 1D velocity) have been obtained at selected phases during Eta Carinae's 5.54-year orbital cycle. The data cubes were collected by mapping the central 1-2" at 0.05" intervals with a 52"x0.1" aperture. Selected forbidden lines, that form in the colliding wind regions, provide information on electron density of the shocked regions, the ionization by the hot secondary companion of the primary wind and how these regions change with orbital phase. By applying various analysis techniques to these data cubes, we can compare and measure temporal changes due to the interactions between the two massive winds. The observations, when compared to current 3D hydrodynamic models, provide insight on Eta Carinae's recent mass-loss history, important for determining the current and future states of this likely nearby supernova progenitor.

McKinnon, Darren; Gull, T. R.; Madura, T.

2014-01-01

228

Preliminary Results for the 2-4 Millimeter Wavelength Continuum Opacity of Ammonia based on New Laboratory Measurements under Simulated Jovian Conditions  

NASA Astrophysics Data System (ADS)

New high-precision laboratory measurements are now being conducted to measure the opacity of ammonia in a hydrogen/helium atmosphere in the 2-4 mm wavelength range. Previous single-wavelength measurements conducted at 3.2 mm (Joiner and Steffes, 1991 and Mohammed, 2005) gave little insight into the frequency dependence of ammonia opacity and were limited by the sensitivity of their equipment. New results have been obtained for the ammonia continuum using an enhanced high precision measurement system with a confocal mirror resonator. Preliminary measurements of the ammonia continuum opacity (2.5 - 4 mm wavelength range) under Jovian conditions have been made with a gas mixture consisting of 84.7% hydrogen, 13.3% helium and 2-4 % ammonia and at pressures of 1-3 bars at 290 K. Future measurements will be conducted at temperatures of 218K and 204K and shorter wavelengths extending down to 2 mm. These results will be used to verify which model best predicts the opacity of ammonia under Jovian conditions at these wavelengths. The 2-4 mm wavelength range has been extensively used for disk averaged emission measurements of the outer planets and for interferometric mapping of Saturn (Griffin and Orton 1993, Muhleman and Berge, 1991 and van de Tak et. al, 1999). These laboratory measurements could potentially influence the interpretation of these observations. This work is supported by the NASA Planetary Atmospheres Program under Grant NNG06GF34G.

Devaraj, Kiruthika; Steffes, P. G.

2007-10-01

229

Plastic repair of the deferent duct with a silicone tubular prosthesis under conditions of a chronic experiment on laboratory animals.  

PubMed

A connective tissue capsule consisting of a thin layer of the connective tissue envelopes the prosthesis by the end of week 1 after replacement of a part of the deferent duct with a silicone tubular prosthesis under conditions of a chronic experiment. By days 17-20 postoperation, two layers are clearly differentiated in the capsule: the outer layer consisted of a thin layer of connective tissue and the inner one consisted of compact connective tissue. The space between the silicone prosthesis and the connective tissue capsule is filled with the seminal fluid. Obturation of the deferent duct forms because of formation of internal spermatogranulomas and atypical growth of the deferent duct epithelium adhering to the prosthesis wall. PMID:18256763

Artyukhin, A A

2007-07-01

230

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

PubMed

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

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

2014-08-01

231

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

PubMed Central

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

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

2013-01-01

232

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

233

Comparison of cyanobacterial microcystin synthetase (mcy) E gene transcript levels, mcy E gene copies, and biomass as indicators of microcystin risk under laboratory and field conditions  

PubMed Central

Increased incidences of mixed assemblages of microcystin-producing and nonproducing cyanobacterial strains in freshwater bodies necessitate development of reliable proxies for cyanotoxin risk assessment. Detection of microcystin biosynthetic genes in water blooms of cyanobacteria is generally indicative of the presence of potentially toxic cyanobacterial strains. Although much effort has been devoted toward elucidating the microcystin biosynthesis mechanisms in many cyanobacteria genera, little is known about the impacts of co-occurring cyanobacteria on cellular growth, mcy gene expression, or mcy gene copy distribution. The present study utilized conventional microscopy, qPCR assays, and enzyme-linked immunosorbent assay to study how competition between microcystin-producing Microcystis aeruginosa CPCC 299 and Planktothrix agardhii NIVA-CYA 126 impacts mcyE gene expression, mcyE gene copies, and microcystin concentration under controlled laboratory conditions. Furthermore, analyses of environmental water samples from the Missisquoi Bay, Quebec, enabled us to determine how the various potential toxigenic cyanobacterial biomass proxies correlated with cellular microcystin concentrations in a freshwater lake. Results from our laboratory study indicated significant downregulation of mcyE gene expression in mixed cultures of M. aeruginosa plus P. agardhii on most sampling days in agreement with depressed growth recorded in the mixed cultures, suggesting that interaction between the two species probably resulted in suppressed growth and mcyE gene expression in the mixed cultures. Furthermore, although mcyE gene copies and McyE transcripts were detected in all laboratory and field samples with measureable microcystin levels, only mcyE gene copies showed significant positive correlations (R2 > 0.7) with microcystin concentrations, while McyE transcript levels did not. These results suggest that mcyE gene copies are better indicators of potential risks from microcystins than McyE transcript levels or conventional biomass proxies, especially in water bodies comprising mixed assemblages of toxic and nontoxic cyanobacteria. PMID:24838591

Ngwa, Felexce F; Madramootoo, Chandra A; Jabaji, Suha

2014-01-01

234

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

NASA Astrophysics Data System (ADS)

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

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

235

Effects of Bacillus thuringiensis Cry toxins on developmental and reproductive characteristics of the predator Orius albidipennis (Hemiptera: Anthocoridae) under laboratory conditions.  

PubMed

The effects of Cry toxins from Bacillus thuringiensis (Berliner) (Bt) on the anthocorid Orius albidipennis Reuter were studied under laboratory conditions. Tritrophic experiments were performed, in which Orius nymphs were fed Helicoverpa armigera (Hübner) larvae reared on a diet with Cry1Ac, Cry1Ab, or Cry2Ab toxins at different concentrations (0, 1, and 10 microg/ml), when supplemented with Ephestia kuehniella Zeller eggs. In complementary experiments, the Bt Cry1Ac toxin was directly fed to Orius nymphs at a very high concentration (1 mg/ml). No effects on prey consumption, developmental time, nymph survival, fecundity, and egg hatching of O. albidipennis were found in either experiment. It can be concluded that the toxins tested do not seem to pose a risk for the anthocorid O. albidipennis, especially when it is exposed through the prey. PMID:18284750

González-Zamora, J E; Camúñez, S; Avilla, C

2007-10-01

236

Effects of glyphosate-based herbicides on survival, development, growth and sex ratios of wood frog (Lithobates sylvaticus) tadpoles. II: agriculturally relevant exposures to Roundup WeatherMax® and Vision® under laboratory conditions.  

PubMed

Glyphosate-based herbicides are currently the most commonly used herbicides in the world. They have been shown to affect survival, growth, development and sexual differentiation of tadpoles under chronic laboratory exposures but this has not been investigated under more environmentally realistic conditions. The purpose of this study is (1) to determine if an agriculturally relevant exposure to Roundup WeatherMax®, a relatively new and understudied formulation, influences the development of wood frog tadpoles (Lithobates sylvaticus) through effects on the mRNA levels of genes involved in the control of metamorphosis; (2) to compare results to the well-studied Vision® formulation (containing the isopropylamine salt of glyphosate [IPA] and polyethoxylated tallowamine [POEA] surfactant) and to determine which ingredient(s) in the formulations are responsible for potential effects on development; and (3) to compare results to recent field studies that used a similar experimental design. In the present laboratory study, wood frog tadpoles were exposed to an agriculturally relevant application (i.e., two pulses) of Roundup WeatherMax® and Vision® herbicides as well as the active ingredient (IPA) and the POEA surfactant of Vision®. Survival, development, growth, sex ratios and mRNA levels of genes involved in tadpole metamorphosis were measured. Results show that Roundup WeatherMax® (2.89 mg acid equivalent (a.e.)/L) caused 100% mortality after the first pulse. Tadpoles treated with a lower concentration of Roundup WeatherMax® (0.21 mg a.e./L) as well as Vision® (2.89 mg a.e./L), IPA and POEA had an increased condition factor (based on length and weight measures in the tadpoles) relative to controls at Gosner stage (Gs) 36/38. At Gs42, tadpoles treated with IPA and POEA had a decreased condition factor. Also at Gs42, the effect on condition factor was dependent on the sex of tadpoles and significant treatment effects were only detected in males. In most cases, treatment reduced the normal mRNA increase of key genes controlling development in tadpoles between Gs37 and Gs42, such as genes encoding thyroid hormone receptor beta in brain, glucocorticoid receptor in tail and deiodinase enzyme in brain and tail. We conclude that glyphosate-based herbicides have the potential to alter mRNA profiles during metamorphosis. However, studies in natural systems have yet to replicate these negative effects, which highlight the need for more ecologically relevant studies for risk assessment. PMID:24912403

Lanctôt, C; Navarro-Martín, L; Robertson, C; Park, B; Jackman, P; Pauli, B D; Trudeau, V L

2014-09-01

237

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

238

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

239

Laboratory measurements of the 3.7-20 cm wavelength opacity of sulfur dioxide and carbon dioxide 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 (see, e.g., Devaraj, K. [2011]. The Centimeter- and Millimeter-Wavelength Ammonia Absorption Spectra under Jovian Conditions. PhD Thesis, Georgia Institute of Technology, Atlanta, GA). Since the emission morphology is related both to surface features and to deep atmospheric absorption from CO2 and SO2 (see, e.g., Butler, B.J., Steffes, P.G., Suleiman, S.H., Kolodner, M.A., Jenkins, J.M. [2001]. Icarus 154, 226-238), 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. Except for a single measurement campaign conducted at a single wavelength (3.2 cm) over 40 years ago (Ho, W., Kaufman, I.A., Thaddeus, P. [1966]. J. Geophys. Res. 71, 5091-5108), no measurements of the centimeter-wavelength properties of any Venus atmospheric constituent have been conducted under conditions characteristic of the deep atmosphere (pressures from 10 to 92 bars and temperatures from 400 to 700 K). New measurements of the microwave properties of SO2 and CO2 at wavelengths from 3.7 to 20 cm have been conducted under simulated conditions for the deep atmosphere of Venus, using a new high-pressure system. Results from this measurement campaign conducted at temperatures from 430 K to 560 K and at pressures up to 92 bars are presented. Results indicate that the model for the centimeter-wavelength opacity from pure CO2 (Ho, W., Kaufman, I.A., Thaddeus, P. [1966]. J. Geophys. Res. 71, 5091-5108), is valid over the entire centimeter-wavelength range under simulated conditions for the deep atmosphere of Venus. Additionally, the laboratory results indicate that both of the models for the centimeter-wavelength opacity of SO2 in a CO2 atmosphere from Suleiman et al. (Suleiman, S.H., Kolodner, M.A., Steffes, P.G. [1996]. J. Geophys. Res. 101, 4623-4635) and from Fahd and Steffes (Fahd, A.K., Steffes, P.G. [1992]. Icarus 97, 200-210) can reliably be used under conditions of the deep atmosphere of Venus.

Steffes, Paul G.; Shahan, Patrick; Christopher Barisich, G.; Bellotti, Amadeo

2015-01-01

240

Similarity and Group Performance  

ERIC Educational Resources Information Center

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

Civettini, Nicole H. W.

2007-01-01

241

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

PubMed Central

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

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

2014-01-01

242

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

243

Scale-up of Escherichia coli growth and recombinant protein expression conditions from microwell to laboratory and pilot scale based on matched k(L)a.  

PubMed

Fermentation optimization experiments are ideally performed at small scale to reduce time, cost and resource requirements. Currently microwell plates (MWPs) are under investigation for this purpose as the format is ideally suited to automated high-throughput experimentation. In order to translate an optimized small-scale fermentation process to laboratory and pilot scale stirred-tank reactors (STRs) it is necessary to characterize key engineering parameters at both scales given the differences in geometry and the mechanisms of aeration and agitation. In this study oxygen mass transfer coefficients are determined in three MWP formats and in 7.5 L and 75 L STRs. k(L)a values were determined in cell-free media using the dynamic gassing-out technique over a range of agitation conditions. Previously optimized culture conditions at the MWP scale were then scaled up to the larger STR scales on the basis of matched k(L)a values. The accurate reproduction of MWP (3 mL) E. coli BL21 (DE3) culture kinetics at the two larger scales was shown in terms of cell growth, protein expression, and substrate utilization for k(L)a values that provided effective mixing and gas-liquid distribution at each scale. This work suggests that k(L)a provides a useful initial scale-up criterion for MWP culture conditions which enabled a 15,000-fold scale translation in this particular case. This work complements our earlier studies on the application of DoE techniques to MWP fermentation optimization and in so doing provides a generic framework for the generation of large quantities of soluble protein in a rapid and cost-effective manner. PMID:17969169

Islam, R S; Tisi, D; Levy, M S; Lye, G J

2008-04-01

244

Gender similarities and differences.  

PubMed

Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research. PMID:23808917

Hyde, Janet Shibley

2014-01-01

245

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

2011-01-01

246

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 28°C, 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. PMID:22856645

2012-01-01

247

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

248

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

NASA Astrophysics Data System (ADS)

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

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

2002-05-01

249

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

250

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

2011-01-01

251

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

252

The influence of host fruit and temperature on the body size of adult Ceratitis capitata (Diptera: Tephritidae) under laboratory and field conditions.  

PubMed

The adult body size of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), varies in natural conditions. Body size is an important fitness indicator in the Mediterranean fruit fly; larger individuals are more competitive at mating and have a greater dispersion capacity and fertility. Both temperature during larval development and host fruit quality have been cited as possible causes for this variation. We studied the influence of host fruit and temperature during larval development on adult body size (wing area) in the laboratory, and determined body size variation in field populations of the Mediterannean fruit fly in eastern Spain. Field flies measured had two origins: 1) flies periodically collected throughout the year in field traps from 32 citrus groves, during the period 2003-2007; and 2) flies evolved from different fruit species collected between June and December in 2003 and 2004. In the lab, wing area of male and female adults varied significantly with temperature during larval development, being larger at the lowest temperature. Adult size also was significantly different depending on the host fruit in which larvae developed. The size of the flies captured at the field, either from traps or from fruits, varied seasonally showing a gradual pattern of change along the year. The largest individuals were obtained during winter and early spring and the smallest during late summer. In field conditions, the size of the adult Mediterannean fruit fly seems apparently more related with air temperature than with host fruit. The implications of this adult size pattern on the biology of C. capitata and on the application of the sterile insect technique are discussed. PMID:22251694

Navarro-Campos, C; Martínez-Ferrer, M T; Campos, J M; Fibla, J M; Alcaide, J; Bargues, L; Marzal, C; Garcia-Marí, F

2011-08-01

253

Accumulation and depuration rates of paralytic shellfish poisoning toxins in the shore crab Telmessus acutidens by feeding toxic mussels under laboratory controlled conditions.  

PubMed

Accumulation and depuration rates of paralytic shellfish poisoning toxins (PSP) in the crab Telmessus acutidens were investigated by feeding toxic and non-toxic mussels under laboratory controlled conditions. The crab accumulated toxins in the hepatopancreas in proportion to the amount of toxic mussels they ingested, and the toxicity in the crab hepatopancreas became 3.2 fold of that in the prey mussels after 20 days of feeding. During depuration, a fast reduction of the total toxicity was observed in the crab, and the retention rate of the toxicity after 5 days depuration with feeding of non-toxic mussels was 45.8+/-18.7%. The reduction of the toxicity was moderated in the later period of depuration, and the retention rates of the total toxicity after 10 and 20 days were 54.1+/-29.8% and 14.5+/-9.0%, respectively. The toxin profiles in the crab and mussel were investigated by high performance liquid chromatography, and reductive conversions of the toxins were observed when the toxins were transferred from the mussel to the crab. Consequently, high concentrations of GTX2 and GTX3, and STX that were not detected in the prey mussels, were found in the crab. PMID:15626365

Oikawa, Hiroshi; Satomi, Masataka; Watabe, Shugo; Yano, Yutaka

2005-02-01

254

Average velocity field of the air flow over the water surface in a laboratory modeling of storm and hurricane conditions in the ocean  

NASA Astrophysics Data System (ADS)

Laboratory experiments on studying the structure of the turbulent air boundary layer over waves were carried out at the Wind-Wave Channel of the Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), in conditions modeling the near-water boundary layer of the atmosphere under strong and hurricane winds and the equivalent wind velocities from 10 to 48 m/s at the standard height of 10 m. A modified technique of Particle Image Velocimetry (PIV) was used to obtain turbulent pulsation averaged velocity fields of the air flow over the water surface curved by a wave and average profiles of the wind velocity. The measurements showed that the logarithmic part of the velocity profile of the air flow in the channel was observed in the immediate vicinity from the water surface (at a distance of 30 mm) and could be detected only using remote methods (PIV). According to the measured velocity profiles, dependences of aerodynamic drag factors of the water surface on the wind velocity at a height of 10 m were retrieved; they were compared with results of contact measurements carried out earlier on the same setup. It is shown that they agree with an accuracy of up to 20%; at moderate and strong wind velocities the coincidence falls within the experimental accuracy.

Kandaurov, A. A.; Troitskaya, Yu. I.; Sergeev, D. A.; Vdovin, M. I.; Baidakov, G. A.

2014-07-01

255

Reconsolidation of Crushed Salt to 250°C Under Hydrostatic and Shear Stress Conditions Scott Broome, Frank Hansen, and SJ Bauer Sandia National Laboratories, Geomechanics Department  

NASA Astrophysics Data System (ADS)

Design, analysis and performance assessment of potential salt repositories for heat-generating nuclear waste require knowledge of thermal, mechanical, and fluid transport properties of reconsolidating granular salt. Mechanical properties, Bulk (K) and Elastic (E) Moduli and Poisson's ratio (?) are functions of porosity which decreases as the surrounding salt creeps inward and compresses granular salt within the rooms, drifts or shafts. To inform salt repository evaluations, we have undertaken an experimental program to determine K, E, and ? of reconsolidated granular salt as a function of porosity and temperature and to establish the deformational processes by which the salt reconsolidates. The experiments will be used to populate the database used in the reconsolidation model developed by Callahan (1999) which accounts for the effects of moisture through pressure solution and dislocation creep, with both terms dependent on effective stress to account for the effects of porosity. Mine-run salt from the Waste Isolation Pilot Program (WIPP) was first dried at 105 °C for a few days. Undeformed right-circular cylindrical sample assemblies of unconsolidated granular salt with an initial porosity of ~ 40%, nominally 10 cm in diameter and 17.5 cm in length, are jacketed in lead. Samples are placed in a pressure vessel and kept at test temperatures of 100, 175 or 250 °C; samples are vented to the atmosphere during the entire test procedure. At these test conditions the consolidating salt is always creeping, the creep rate increases with increasing temperature and stress and decreases as porosity decreases. In hydrostatic tests, confining pressure is increased to 20 MPa with periodic unload/reload loops to determine K. Volume strain increases with increasing temperature. In shear tests at 2.5 and 5 MPa confining pressure, after confining pressure is applied, the crushed salt is subjected to a differential stress, with periodic unload/reload loops to determine E and ?. At predetermined differential stress levels the stress is held constant and the salt consolidates. Displacement gages mounted on the samples show little lateral deformation until the samples reach a porosity of ~10%. Interestingly, vapor is vented in tests at 250°C and condenses at the vent port. Release of water is not observed in the lower two test temperatures. It is hypothesized that the water originates from fluid inclusions, which were made accessible by intragranular deformational processes including decrepitation. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Broome, S. T.

2012-12-01

256

Assessment of environmental stress by the micronucleus and comet assays on Limnoperna fortunei exposed to Guaíba hydrographic region samples (Brazil) under laboratory conditions.  

PubMed

The Guaíba Basin is a source of drinking water for Porto Alegre (RS, Brazil). The water from this basin receives industrial, urban, and rural waste from many sources. The mussel species Limnoperna fortunei was chosen based on population data, distribution, and sensitivity. Previous tests with comet assay and micronuclei frequency in this freshwater mussel have shown to be successful in biomonitoring studies. The aim of this study was to evaluate the genotoxic contamination of the Guaíba Lake Hydrographic Region, through the determination of damage by the micronuclei and comet assays in L. fortunei (golden mussel). Nine sampling sites were evaluated in three different seasons: five sites in the mouths of the main rivers that flow into Guaíba lake; one site at the mouth of a stream; one major site of sewage discharge; two sites at Guaíba lake, near a sewage discharge; and the control site in a preservation area. DNA damage was detected by the single cell gel assay, as well as the frequency of micronuclei in hemocytes of mussels exposed under laboratory conditions for 7 days to water and sediment samples. Significant results were found in different seasons in almost all sampling sites (P<0.05, ANOVA Dunnet's test). Most of the positive results were found in samples affected mainly by urban effluents. It was possible to observe that there was a weak relation between mutagenic and genotoxic responses and mussels inorganic elements contents. Seasonal variation was observed at different sampling sites, but always indicating a huge contamination near urban sewage discharge. These results are consistent with previous studies, allowing us to infer that urban contamination is the biggest problem in this region. It is also possible to infer that L. fortunei is a good sentinel organism for the Guaíba Basin. PMID:17267262

Villela, Izabel Vianna; de Oliveira, Iuri Marques; Silveira, Juliano Coelho; Dias, Johnny Ferraz; Henriques, João Antonio Pêgas; da Silva, Juliana

2007-04-01

257

Laboratory Evaluation of the Effect of HNO3 Uptake on Frost Point Hygrometer Measurement of Water Vapor under UT/LS Conditions  

NASA Astrophysics Data System (ADS)

Chilled mirror hygrometers (CMH) are widely used to measure water vapor in the troposphere and lower stratosphere from balloon-borne sondes. Systematic discrepancies among in situ water vapor instruments have been observed at low water vapor mixing ratios (< 5 ppm) in the upper troposphere and lower stratosphere (UT/LS). Understanding the source of the measurement discrepancies is important for a more accurate and reliable determination of water vapor abundance in this region. We have conducted a laboratory study to investigate the potential interference of gas-phase nitric acid (HNO3) with the measurement of frost point temperature, and consequently the water vapor mixing ratio, determined by CMH under conditions representative of operation in the UT/LS. No detectable interference in the measured frost point temperature was found for HNO3 mixing ratios of up to 2 ppb for exposure times up to 150 minutes. HNO3 was observed to co-condense on the mirror frost, with the adsorbed mass increasing linearly with time at constant exposure levels. Over the duration of a typical balloon sonde ascent (90-120 min), the maximum accumulated HNO3 amounts were comparable to monolayer coverage of the geometric mirror surface area, which likely corresponds to small fractional coverage of the actual frost layer surface area. This small amount of co-condensed HNO3 is consistent with the observed lack of HNO3 interference in the frost point measurement because the CMH utilizes significant reductions (>10%) in surface reflectivity by the condensate for the determination of H2O.

Thornberry, T.; Gierczak, T.; Gao, R.; Voemel, H.; Watts, L.; Burkholder, J. B.; Fahey, D. W.

2010-12-01

258

NCBI More Information: Similarity  

NSDL National Science Digital Library

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

Information, National C.

259

SIMILARITY NETWORK FOR SEMANTIC WEB SERVICES SUBSTITUTION  

E-print Network

SIMILARITY NETWORK FOR SEMANTIC WEB SERVICES SUBSTITUTION Chantal Cherifi LE2I Laboratory, Burgundy is performed on a benchmark of semantically annotated Web services. Results show that this approach allows a more detailed analysis of substitutable Web services. Keywords - Semantic Web services, Functional

Paris-Sud XI, Université de

260

Exploration Laboratory Analysis FY13  

NASA Technical Reports Server (NTRS)

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

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

2013-01-01

261

Self-similar energies on p.c.f. self-similar B.M. Hambly  

E-print Network

Self-similar energies on p.c.f. self-similar fractals B.M. Hambly V. Metz A. Teplyaev November 4, 2005 Abstract On a large class of p.c.f. (finitely ramified) self-similar fractals with possibly little such fractal, under a certain condition, there are corresponding refinement weights which support a unique self

Jordan, Jonathan

262

Self-similar energies on p.c.f. self-similar B.M. Hambly  

E-print Network

Self-similar energies on p.c.f. self-similar fractals B.M. Hambly V. Metz A. Teplyaev January 22, 2006 Abstract On a large class of p.c.f. (finitely ramified) self-similar fractals with possibly little such fractal, under a certain condition, there are corresponding refinement weights which support a unique self

Teplyaev, Alexander

263

Similarities to Lunar Highlands  

NASA Technical Reports Server (NTRS)

After passing Mercury the first time and making a trip around the Sun, Mariner 10 again flew by Mercury on September 21 at 1:59 PMPDT. This encounter brought the spacecraft in front of Mercury in the southern hemisphere.

Much of Mercury looks like the lunar highlands, a scene carved by billions of years of impact craters. This image (FDS 166724)was taken when Mariner 10 was near its closest approach to the planet during the second encounter, about 50,000 km. This image is found near the center of the area not imaged during the first encounter.

The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

Image Credit: NASA/JPL/Northwestern University

1974-01-01

264

Postembryonic development and food consumption of Dichroplus elongatus Giglio-Tos and Dichroplus maculipennis (Blanchard) (Orhtoptera: Acrididae: Melanoplinae) under laboratory conditions.  

PubMed

Dichroplus maculipennis (Blanchard) and D. elongatus Giglio-Tos are two of the most important melanoplines in Argentina, both ecologically and economically. The postembryonic development and forage loss (consumption of Bromus brevis Ness + fallen material) caused by older nymphs (instars IV, V, VI) and adults of both species were studied under controlled conditions (30ºC, 14L:10D, 40% RH). Five nymphal instars were recorded in D. elongatus, and six in D. maculipennis. Total nymphal development was similar in both species (D. elongatus: 32 ± 0.70 days; D. maculipennis: 34.5 ± 0.37 days). Daily consumption increased from nymphal instars to pre-reproductive adult stage. In both species, pre-reproductive females had higher consumption rates than other stages considered (D. elongatus: 30.6 ± 0.56 mg dry weight/day; D. maculipennis: 48.7 ± 0.74 mg dry weight/day). In the reproductive stage, consumption decreased significantly in both sexes. When feeding, D. maculipennis let some plant material to drop, increasing total loss. The percentage of fallen material was greater in reproductive adults, representing 3.9% and 2.9% of the total daily loss for males and females, respectively. Females and males of D. maculipennis were heavier than those of D. elongatus (P < 0.05), and daily consumption was significantly higher (P < 0.05). Regardless sex and reproductive status, adults of D. maculipennis consumed 29.1 ± 0.64 mg dry weight/day on average, while one of D. elongatus 20.0 ± 0.3 mg dry weight/ day. PMID:21584399

Mariottini, Y; de Wysiecki, M L; Lange, C E

2011-01-01

265

Zoophthora radicans (Zygomycetes: Entomophthorales) conidia production from naturally infected Empoasca kraemeri and dry-formulated mycelium under laboratory and field conditions  

Microsoft Academic Search

Laboratory and field studies were conducted to assess the effects of temperature on sporulation of a dried-mycelium formulation of the entomophthoralean fungus Zoophthora radicans and to compare sporulation of laboratory-produced\\/formulated fungus versus fungus occurring on cadavers of naturally infected Empoasca leafhoppers. Conidia production by the formulation increased from 3.1×104 to a maximum of 13.7×104 conidia\\/mg (dry weight) over the temperature

S. P Wraight; S Galaini-Wraight; R. I Carruthers; D. W Roberts

2003-01-01

266

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?¹, UN+NSC, UN+Na?S?O? and UN+CaCl? and incubated at 22°C 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?¹ was accumulated over 50 d (maximum 93 mg kg?¹) 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

2011-03-01

267

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

NASA Astrophysics Data System (ADS)

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

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

2014-10-01

268

Laboratory dynamos  

NASA Astrophysics Data System (ADS)

The magnetism of the planets, including Earth, is generated by dynamo action, i.e. self-generation of a magnetic field due to the fluid motion of liquid iron inside the planetary cores. During the last decades, laboratory experiments became an essential part of the research on dynamo action, complementing both observations and theory. In this talk, I will review some recent results of the Von-Karman Sodium (VKS) experiment. The VKS experiment has been designed to achieve dynamo action in a turbulent flow of liquid metal. In this experiment, 150 liters of liquid sodium are stirred by the counter-rotation of two bladed discs in a cylindrical tank. When the discs are rotating sufficiently fast, a dipolar magnetic field, aligned with the axis of rotation, is generated by dynamo action. In addition,a lot of dynamical regimes can be observed, like chaotic polarity inversions of the field very similar to geomagnetic reversals. In some cases, the experiment can also generate hemispherical dynamos similar to some planetary fields. These different behaviors will be described within the framework of simple theoretical models. I will discuss how these results, and the corresponding theoretical descriptions, can provide a better understanding of some aspects of the geomagnetic field dynamics. Finally, I will present current perspectives for the next generation of laboratory dynamo experiments.

Gissinger, Christophe

2014-05-01

269

Gibbs Paradox and Similarity Principle  

E-print Network

As no heat effect and mechanical work are observed, we have a simple experimental resolution of the Gibbs paradox: both the thermodynamic entropy of mixing and the Gibbs free energy change are zero during the formation of any ideal mixtures. Information loss is the driving force of these spontaneous processes. Information is defined as the amount of the compressed data. Information losses due to dynamic motion and static symmetric structure formation are defined as two kinds of entropies - dynamic entropy and static entropy, respectively. There are three laws of information theory, where the first and the second laws are analogs of the two thermodynamic laws. However, the third law of information theory is different: for a solid structure of perfect symmetry (e.g., a perfect crystal), the entropy (static entropy for solid state) S is the maximum. More generally, a similarity principle is set up: if all the other conditions remain constant, the higher the similarity among the components is, the higher the value of entropy of the mixture (for fluid phases) or the assemblage (for a static structure or a system of condensed phases) or any other structure (such as quantum states in quantum mechanics) will be, the more stable the mixture or the assemblage will be, and the more spontaneous the process leading to such a mixture or an assemblage or a chemical bond will be.

Shu-Kun Lin

2008-07-28

270

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

Microsoft Academic Search

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,

Frank Stanley Gulczinski III

1999-01-01

271

Similarity increases altruistic punishment in humans.  

PubMed

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

Mussweiler, Thomas; Ockenfels, Axel

2013-11-26

272

An update of hydrologic conditions and distribution of selected constituents in water, Snake River Plain aquifer, Idaho National Laboratory, Idaho, Emphasis 1999-2001  

USGS Publications Warehouse

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 underlying the INL. The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, maintains ground-water monitoring networks at the INL to determine hydrologic trends, and to delineate the movement of radiochemical and chemical wastes in the aquifer. This report presents an analysis of water-level and water-quality data collected from wells in the USGS ground-water monitoring networks during 1999-2001. Water in the Snake River Plain aquifer moves principally through fractures and interflow zones in basalt, generally flows southwestward, and eventually discharges at springs along the Snake River. The aquifer is recharged principally from infiltration of irrigation water, infiltration of streamflow, ground-water inflow from adjoining mountain drainage basins, and infiltration of precipitation. Water levels in wells rose in the northern and west-central parts of the INL by 1 to 3 feet, and declined in the southwestern parts of the INL by up to 4 feet during 1999-2001. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INL generally decreased or remained constant during 1999-2001. Decreases in concentrations were attributed to decreased rates of radioactive-waste disposal, radioactive decay, changes in waste-disposal methods, and dilution from recharge. Tritium concentrations in water samples decreased as much as 8.3 picocuries per milliliter (pCi/mL) during 1999-2001, ranging from 0.43?0.14 to 13.6?0.6 pCi/mL in October 2001. Tritium concentrations in five wells near the Idaho Nuclear Technology and Engineering Center (INTEC) increased a few picocuries per milliliter from October 2000 to October 2001. Strontium-90 concentrations decreased or remained constant during 1999-2001, ranging from 2.1?0.6 to 42.4?1.4 pCi/L in October 2001. During 1999-2001, concentrations of cesium-137, plutonium-238, and plutonium-239, -240 (undivided) were less than the reporting level in water samples from all wells sampled at the INL. The concentration of americium-241 in one sample was 0.003?0.001 pCi/L, the reporting level for that constituent. Cobalt-60 was not detected in any samples collected during 1999-2001. Changes in detectable concentrations of nonradioactive chemical constituents in water from the Snake River Plain aquifer at the INL varied during 1999-2001. In October 2001, water from one well south of the Reactor Technology Complex (RTC) [known as the Test Reactor Area (TRA) until 2005] contained 139 micrograms per liter (?g/L) of chromium, a decrease from the concentration of 168 ?g/L detected in October 1998. Other water samples contained from less than 16.7 to 21.3 ?g/L of chromium. In October 2001, concentrations of sodium in water samples from most of the wells in the southern part of the INL were larger than the background concentration of 10 mg/L, but were similar to or slightly less than October 1998 concentrations. The largest sodium concentration was 75 milligrams per liter (mg/L) in water from well USGS 113. In 2001, chloride concentrations in most water samples from the INTEC and the Central Facilities Area (CFA) exceeded ambient concentrations of 10 and 20 mg/L, respectively. Chloride concentrations in water from wells near the RTC were less than 20 mg/L. At the Radioactive Waste Management Complex (RWMC), chloride concentrations in water from wells USGS 88, 89, and 120 were 81, 40, and 23 mg/L, respectively. Concentrations of chloride in all other wells near the RWMC were less than 19 mg/L. During 2001, concentrations of sulfate in water from two wells near the RTC, two wells near the RWMC, and one well near the CFA exceeded 40 mg/L, the estimated background concentration of sulfate in the Snake River

Davis, Linda C.

2006-01-01

273

Similarity Measures for Structured Representations  

Microsoft Academic Search

A key concept in case-based reasoning is similarity. In this paper, we first propose a similarity measure for structured representations that is based on graph edit operations. Then we show how this similarity measure can be computed by means of state space search. Subsequently, subgraph isomorphism is considered as a special case of graph similarity and a new efficient algorithm

Horst Bunke; Bruno T. Messmer

1993-01-01

274

Preliminary Results for the 2-4 Millimeter Wavelength Continuum Opacity of Ammonia based on New Laboratory Measurements under Simulated Jovian Conditions  

Microsoft Academic Search

New high-precision laboratory measurements are now being conducted to measure the opacity of ammonia in a hydrogen\\/helium atmosphere in the 2-4 mm wavelength range. Previous single-wavelength measurements conducted at 3.2 mm (Joiner and Steffes, 1991 and Mohammed, 2005) gave little insight into the frequency dependence of ammonia opacity and were limited by the sensitivity of their equipment. New results have

Kiruthika Devaraj; P. G. Steffes

2007-01-01

275

Learning task-specific similarity  

E-print Network

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

Shakhnarovich, Gregory

2006-01-01

276

Self-Similar Abe Karplus  

E-print Network

-----------------------------------------------------------------------------------------References! 27 ~2~ #12;Introduction For my science fair project I am studying fractals. SeveralSelf-Similar Sierpinski Fractals Abe Karplus Science Fair 2008 ~1~ #12;Self-Similar Sierpinski

Karplus, Kevin

277

Interdisciplinary Interactions in Underground Laboratories  

Microsoft Academic Search

Many of underground facilities, ranging from simple cavities to fully equipped laboratories, have been established worldwide (1) to evaluate the impacts of emplacing nuclear wastes in underground research laboratories (URLs) and (2) to measure rare physics events in deep underground laboratories (DULs). In this presentation, we compare similarities and differences between URLs and DULs in focus of site characterization, in

J. S. Wang; A. Bettini

2010-01-01

278

Similarity queries in image databases  

Microsoft Academic Search

Query-by-content image database will be based on similarity, rather than on matching, where similarity is a measure that is defined and meaningful for every pair of images in the image space. Since it is the human user that, in the end, has to be satisfied with the results of the query, it is natural to base the similarity measure that

Simone Santini; Ramesh Jain

1996-01-01

279

Health and Survival of Red Abalone Haliotis rufescens from San Miguel Island, California, USA, in a Laboratory Simulation of La Niña and El Niño Conditions  

Microsoft Academic Search

The variability in Southern California's marine climate is dominated by the El Niño–Southern Oscillation, with cycling between El Niño events (characterized by warm water, low productivity, and frequent storms) and La Niña events (which exhibit the opposite conditions). Relative to the mainland and other Channel Islands, San Miguel Island (SMI) consistently maintains cooler water temperatures and supports significant populations of

James D. Moore; Blythe C. Marshman; Calvin S. Y. Chun

2011-01-01

280

Interruption-similarity effects during discourse processing  

PubMed Central

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

Ledoux, Kerry; Gordon, Peter C.

2006-01-01

281

Personalized recommendation with corrected similarity  

E-print Network

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

Zhu, Xuzhen; Cai, Shimin

2014-01-01

282

Why similar protein sequences encode similar three-dimensional structures?  

Microsoft Academic Search

Evolutionarily related proteins have similar sequences. Such similarity is called homology and can be described using substitution\\u000a matrices such as Blosum 60. Naturally occurring homologous proteins usually have similar stable tertiary structures and this\\u000a fact is used in so-called homology modeling. In contrast, the artificial protein designed by the Regan group has 50% identical\\u000a sequence to the B1 domain of

Szymon Kaczanowski; Piotr Zielenkiewicz

2010-01-01

283

Laboratory Measurments of the 3.7-20 cm Wavelength Opacity of Sulfur Dioxide and Carbon Dioxide 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. Except for a single measurement campaign conducted at a single wavelength (3.2 cm) over 40 years ago (Ho et al., JGR 71, 1966), no measurements of the centimeter-wavelength properties of any Venus atmospheric constituent have been conducted under conditions characteristic of the deep atmosphere (pressures from 10-92 Bars and temperatures from 400-700 K). New measurements of the microwave properties of SO2 and CO2 at wavelengths from 3.7-20 cm are now being conducted under simulated conditions for the deep atmosphere of Venus, using a new high-pressure system. Initial results from this measurement campaign conducted at 430 K and at pressures up to 92 Bars will be presented. This work is supported by the NASA Planetary Atmospheres Program under Grant NNX11AD66G.

Steffes, Paul G.; Barisich, C.

2012-10-01

284

The Baryonic Self Similarity of Dark Matter  

NASA Astrophysics Data System (ADS)

The cosmological simulations indicates that dark matter halos have specific self-similar properties. However, the halo similarity is affected by the baryonic feedback. By using momentum-driven winds as a model to represent the baryon feedback, an equilibrium condition is derived which directly implies the emergence of a new type of similarity. The new self-similar solution has constant acceleration at a reference radius for both dark matter and baryons. This model receives strong support from the observations of galaxies. The new self-similar properties imply that the total acceleration at larger distances is scale-free, the transition between the dark matter and baryons dominated regime occurs at a constant acceleration, and the maximum amplitude of the velocity curve at larger distances is proportional to M 1/4. These results demonstrate that this self-similar model is consistent with the basics of modified Newtonian dynamics (MOND) phenomenology. In agreement with the observations, the coincidence between the self-similar model and MOND breaks at the scale of clusters of galaxies. Some numerical experiments show that the behavior of the density near the origin is closely approximated by a Einasto profile.

Alard, C.

2014-06-01

285

Reading the Envelope: Understanding Visual Similarity Matrices Joseph A. Cottam  

E-print Network

Department, Indiana University Ben Martin Open Systems Laboratory, Indiana University Chris Mueller Open the characteristics of the visual similiarity matrix image. Keywords: Visual Similarity Matrix, Matrix Ordering similarity matrices (VSMs) are essentially a visual represen- tation of a graph's adjacency matrix. A dot

Lumsdaine, Andrew

286

Effects of methoxyfenozide, indoxacarb, and other insecticides on the beneficial egg parasitoid Trichogramma nr. brassicae (Hymenoptera: Trichogrammatidae) under laboratory and field conditions.  

PubMed

Trichogramma nr. brassicae is a common egg parasitoid of Helicoverpa species in Australian processing tomatoes, but its effectiveness can be severely curtailed by insecticide applications. To identify insecticides that are potentially compatible with this species, the effects of seven insecticides, including newly introduced compounds and a surfactant, were screened in laboratory and glasshouse assays for their toxicity to the wasps. Assays involved direct applications on adults, residual effects on adults, and applications on life stages still inside the host. Methoxyfenozide and indoxacarb were not toxic to Trichogramma in any assay when applied at field rates. Naled and chlorfenapyr caused 100% mortality when directly applied to adults, and 95% mortality when adults were exposed to residues of these chemicals within 24 h of application. The effects of naled residues were short lived (<48 h). Naled and chlorfenapyr were also toxic when applied to Trichogramma developing inside host eggs, reducing emergence of adults by >25%. Imidacloprid, emamectin, and tau-fluvalinate were toxic in some experiments; they caused >97% mortality in adults 1 h after direct application and in residue assays they caused 23-64% mortality during the first 24 h. In field trials, methoxyfenozide had no harmful effects on emergence from sprayed parasitized eggs, whereas indoxacarb had a small impact (<8%) on emergence. Methoxyfenozide and indoxacarb are potentially suitable for inclusion in integrated pest management strategies for management of Helicoverpa because they do not influence adult survival or development of immature stages, whereas other chemicals need to be treated cautiously. PMID:14503578

Hewa-Kapuge, Swarna; McDougall, Sandra; Hoffmann, Ary A

2003-08-01

287

Repellency of Cinnamomum cassia bark compounds and cream containing cassia oil to Aedes aegypti (Diptera: Culicidae) under laboratory and indoor conditions.  

PubMed

Patch and skin bioassays were used in laboratory and indoor tests to evaluate the repellency of (E)-cinnamaldehyde, identified in Cinnamomum cassia Blume bark and essential oil, and a cream containing 5% (w/w) cassia oil against Aedes aegypti (L.) females. Results were compared with those of a known C. cassia compound cinnamyl alcohol, N,N-diethyl-m-toluamide (DEET) and two commercial repellents: MeiMei cream containing citronella and geranium oils and Repellan S aerosol containing 19% DEET. In patch bioassay tests with A. aegypti females, (E)-cinnamaldehyde at 0.153 mg cm(-2) and DEET at 0.051 mg cm(-2) provided 93 and 89% protection at 40 min after exposure. In skin bioassay tests, (E)-cinnamaldehyde at 0.051 mg cm(-2) and DEET at 0.025 mg cm(-2) provided 87 and 95% protection at 30 min after application. (E)-Cinnamaldehyde was significantly more effective than cinnamyl alcohol in both bioassays. In indoor tests with four human volunteers, 5% cassia oil cream provided 94, 83 and 61% protection against A. aegypti females exposed for 30, 50 and 70 min after application respectively. Cassia oil cream was a slightly less effective repellent than MeiMei cream. Repellan S aerosol provided 91% repellency at 120 min after application. Products containing cassia oil merit further study as potential repellents for the protection of humans and domestic animals from blood-feeding vectors and the diseases they transmit. PMID:16894642

Chang, Kyu-Sik; Tak, Jun-Hyung; Kim, Soon-Il; Lee, Won-Ja; Ahn, Young-Joon

2006-11-01

288

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

289

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

NASA Technical Reports Server (NTRS)

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

Steffes, P. G.

1985-01-01

290

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

291

Similarity Queries in Image Database  

Microsoft Academic Search

Query-by-content image database will be based onsimilarity, rater than on matching, where similarity isa measure that is defined and meaningful for every pairof images in the image space. Since it is the humanuser that, in the end, has to be satisfied with the resultsof the query, it is natural to base the similarity measurethat we will use on the characteristics

Simone Santini; Ramesh Jain

1996-01-01

292

Similarity Search in Trajectory Databases  

Microsoft Academic Search

Trajectory Database (TD) management is a relatively new topic of database research, which has emerged due to the explosion of mobile devices and positioning technologies. Trajectory similarity search forms an important class of queries in TD with applications in trajectory data analysis and spatiotemporal knowledge discovery. In contrast to related works which make use of generic similarity metrics that virtually

Nikos Pelekis; Ioannis Kopanakis; Gerasimos Marketos; Irene Ntoutsi; Gennady L. Andrienko

2007-01-01

293

Multivariate Time Series Similarity Searching  

PubMed Central

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

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

2014-01-01

294

Environmental Conditions Environmental Conditions  

E-print Network

Environmental Conditions Environmental Conditions Appendix II The unique geology, hydrology and instream habitat. This chapter examines how environmental conditions in the Deschutes watershed affect, the discussion characterizes the environmental conditions within three watershed areas: the Lower Deschutes

295

Physiological and psychological responses to outdoor vs. laboratory cycling.  

PubMed

The purpose of this study was to determine the physiological and psychological responses to laboratory vs. outdoor cycling. Twelve recreationally trained male cyclists participated in an initial descriptive testing session and 2 experimental trials consisting of 1 laboratory and 1 outdoor session, in a randomized order. Participants were given a standardized statement instructing them to give the same perceived effort for both the laboratory and outdoor 40-km trials. Variables measured include power output, heart rate (HR), core temperature, skin temperature, body weight, urine specific gravity (USG), Rating of Perceived Exertion (RPE), attentional focus, and environmental conditions. Wind speed was higher in the outdoor trial than in the laboratory trial (2.5 ± 0.6 vs. 0.0 ± 0.0 m·s-1, p = 0.02) whereas all other environmental conditions were similar. Power output (208.1 ± 10.2 vs. 163.4 ± 11.8 W, respectively, p < 0.001) and HR (152 ± 4 and 143 ± 6 b·min-1, respectively, p = 0.04) were higher in the outdoor trial than in the laboratory trial. Core temperature was similar, whereas skin temperature was cooler during the outdoor trial than during the laboratory trial (31.4 ± 0.3 vs. 33.0 ± 0.2° C, respectively, p < 0.001), thus creating a larger thermal gradient between the core and skin outdoors. No significant differences in body weight, USG, RPE, or attentional focus were observed between trials. These data indicate that outdoor cycling allows cyclists to exercise at a higher intensity than in laboratory cycling, despite similar environmental conditions and perceived exertion. In light of this, cyclists may want to ride at a higher perceived exertion in indoor settings to acquire the same benefit as they would from an outdoor ride. PMID:24476776

Mieras, Molly E; Heesch, Matthew W S; Slivka, Dustin R

2014-08-01

296

Language Laboratories.  

ERIC Educational Resources Information Center

This history of the language laboratory and the factors influencing its growth are briefly traced. Materials and equipment are described, and the problems involved in a laboratory operation are indicated. Also considered is the use of the language laboratory as a teaching machine and as a research device for education in general. A bibliography…

Mathieu, Gustave

1962-01-01

297

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 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

2012-01-01

298

Subterranean microbial populations metabolize hydrogen and acetate under in situ conditions in granitic groundwater at 450 m depth in the Äspö 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

2012-07-01

299

Selection of USSR foreign similarity regions  

NASA Technical Reports Server (NTRS)

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

Disler, J. M. (principal investigator)

1982-01-01

300

An update of hydrologic conditions and distribution of selected constituents in water, Snake River Plain aquifer and perched groundwater zones, Idaho National Laboratory, Idaho, emphasis 2006-08  

USGS Publications Warehouse

Since 1952, radiochemical and chemical wastewater discharged to infiltration ponds (also called percolation ponds), evaporation ponds, and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the eastern Snake River Plain aquifer and perched groundwater zones underlying the INL. The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, maintains groundwater monitoring networks at the INL to determine hydrologic trends, and to delineate the movement of radiochemical and chemical wastes in the aquifer and in perched groundwater zones. This report presents an analysis of water-level and water-quality data collected from aquifer and perched groundwater wells in the USGS groundwater monitoring networks during 2006-08. Water in the Snake River Plain aquifer primarily moves through fractures and interflow zones in basalt, generally flows southwestward, and eventually discharges at springs along the Snake River. The aquifer primarily is recharged from infiltration of irrigation water, infiltration of streamflow, groundwater inflow from adjoining mountain drainage basins, and infiltration of precipitation. From March-May 2005 to March-May 2008, water levels in wells generally remained constant or rose slightly in the southwestern corner of the INL. Water levels declined in the central and northern parts of the INL. The declines ranged from about 1 to 3 feet in the central part of the INL, to as much as 9 feet in the northern part of the INL. Water levels in perched groundwater wells around the Advanced Test Reactor Complex (ATRC) also declined. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INL generally decreased or remained constant during 2006-08. Decreases in concentrations were attributed to decreased rates of radioactive-waste disposal, radioactive decay, changes in waste-disposal methods, and dilution from recharge and underflow. In April or October 2008, reportable concentrations of tritium in groundwater ranged from 810 ? 70 to 8,570 ? 190 picocuries per liter (pCi/L), and the tritium plume extended south-southwestward in the general direction of groundwater flow. Tritium concentrations in water from wells completed in shallow perched groundwater at the ATRC were less than the reporting levels. Tritium concentrations in deep perched groundwater exceeded the reporting level in 11 wells during at least one sampling event during 2006-08 at the ATRC. Tritium concentrations from one or more zones in each well were reportable in water samples collected at various depths in six wells equipped with multi-level WestbayTM packer sampling systems. Concentrations of strontium-90 in water from 24 of 52 aquifer wells sampled during April or October 2008 exceeded the reporting level. Concentrations ranged from 2.2 ? 0.7 to 32.7 ? 1.2 pCi/L. Strontium-90 has not been detected within the eastern Snake River Plain aquifer beneath the ATRC partly because of the exclusive use of waste-disposal ponds and lined evaporation ponds rather than using the disposal well for radioactive-wastewater disposal at ATRC. At the ATRC, the strontium-90 concentration in water from one well completed in shallow perched groundwater was less than the reporting level. During at least one sampling event during 2006-08, concentrations of strontium-90 in water from nine wells completed in deep perched groundwater at the ATRC were greater than reporting levels. Concentrations ranged from 2.1?0.7 to 70.5?1.8 pCi/L. At the Idaho Nuclear Technology and Engineering Center (INTEC), the reporting level was exceeded in water from two wells completed in deep perched groundwater. During 2006-08, concentrations of cesium-137, plutonium-238, and plutonium-239, -240 (undivided), and americium-241 were less than the reporting level in water samples from all wells and all zones in wells equipped with multi-level WestbayTM packer sampling systems

Davis, Linda C.

2010-01-01

301

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

302

Sibling similarity in family formation.  

PubMed

Sibling studies have been widely used to analyze the impact of family background on socioeconomic and, to a lesser extent, demographic outcomes. We contribute to this literature with a novel research design that combines sibling comparisons and sequence analysis to analyze longitudinal family-formation trajectories of siblings and unrelated persons. This allows us to scrutinize in a more rigorous way whether sibling similarity exists in family-formation trajectories and whether siblings' shared background characteristics, such as parental education and early childhood family structure, can account for similarity in family formation. We use Finnish register data from 1987 through 2007 to construct longitudinal family-formation trajectories in young adulthood for siblings and unrelated dyads (N = 14,257 dyads). Findings show that family formation is moderately but significantly more similar for siblings than for unrelated dyads, also after controlling for crucial parental background characteristics. Shared parental background characteristics add surprisingly little to account for sibling similarity in family formation. Instead, gender and the respondents' own education are more decisive forces in the stratification of family formation. Yet, family internal dynamics seem to reinforce this stratification such that siblings have a higher probability to experience similar family-formation patterns. In particular, patterns that correspond with economic disadvantage are concentrated within families. This is in line with a growing body of research highlighting the importance of family structure in the reproduction of social inequality. PMID:25367282

Raab, Marcel; Fasang, Anette Eva; Karhula, Aleksi; Erola, Jani

2014-12-01

303

Perturbations of self-similar Bondi accretion  

E-print Network

The question of stability of steady spherical accretion has been studied for many years and, recently, the concept of spatial instability has been introduced. Here we study perturbations of steady spherical accretion flows (Bondi solutions), restricting ourselves to the case of self-similar flow, as a case amenable to analytic treatment and with physical interest. We further restrict ourselves to its acoustic perturbations. The radial perturbation equation can be solved in terms of Bessel functions. We study the formulation of adequate boundary conditions and decide for no matter-flux-perturbation conditions (at the Bondi radius and at r=0). We also consider the problem of initial conditions and time evolution, in particular, of radial perturbations. No spatial instability at r=0 is found. The time evolution is such that perturbations eventually become ergodic-like and show no trace of instability or of acquiring any remarkable pattern.

Jose Gaite

2005-11-21

304

What Difference Reveals about Similarity  

ERIC Educational Resources Information Center

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

Sagi, Eyal; Gentner, Dedre; Lovett, Andrew

2012-01-01

305

Crowdsourced Trace Similarity with Smartphones  

E-print Network

traces to the query processor. SmartTrace+, relies on an in-situ data storage model and intelligent top than competitive approaches. Index Terms--Crowdsourcing, Trajectory Similarity Search, Smartphones for monetary or ethical (i.e., intellec- tual satisfaction) benefit through an open call. Examples

Zeinalipour, Demetris

306

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

307

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.

308

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

309

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

PubMed

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

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

2014-05-01

310

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Mycology. 493.1203 Section 493.1203...Testing § 493.1203 Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the...

2010-10-01

311

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Mycology. 493.1203 Section 493.1203...Testing § 493.1203 Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the...

2013-10-01

312

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Mycology. 493.1203 Section 493.1203...Testing § 493.1203 Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the...

2012-10-01

313

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Mycology. 493.1203 Section 493.1203...Testing § 493.1203 Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the...

2011-10-01

314

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: Mycology. 493.1203 Section 493.1203...Testing § 493.1203 Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the...

2014-10-01

315

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Toxicology. 493.1213 Section 493.1213...Testing § 493.1213 Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2011-10-01

316

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Toxicology. 493.1213 Section 493.1213...Testing § 493.1213 Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2012-10-01

317

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: Toxicology. 493.1213 Section 493.1213...Testing § 493.1213 Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2014-10-01

318

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Toxicology. 493.1213 Section 493.1213...Testing § 493.1213 Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2010-10-01

319

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Toxicology. 493.1213 Section 493.1213...Testing § 493.1213 Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2013-10-01

320

42 CFR 493.1221 - Condition: Cytology.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

321

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Virology. 493.1205 Section 493.1205...Testing § 493.1205 Condition: Virology. If the laboratory provides services in the subspecialty of Virology, the laboratory must meet the...

2011-10-01

322

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

323

Similarity Measures for Protein Ensembles  

PubMed Central

Analyses of similarities and changes in protein conformation can provide important information regarding protein function and evolution. Many scores, including the commonly used root mean square deviation, have therefore been developed to quantify the similarities of different protein conformations. However, instead of examining individual conformations it is in many cases more relevant to analyse ensembles of conformations that have been obtained either through experiments or from methods such as molecular dynamics simulations. We here present three approaches that can be used to compare conformational ensembles in the same way as the root mean square deviation is used to compare individual pairs of structures. The methods are based on the estimation of the probability distributions underlying the ensembles and subsequent comparison of these distributions. We first validate the methods using a synthetic example from molecular dynamics simulations. We then apply the algorithms to revisit the problem of ensemble averaging during structure determination of proteins, and find that an ensemble refinement method is able to recover the correct distribution of conformations better than standard single-molecule refinement. PMID:19145244

Lindorff-Larsen, Kresten; Ferkinghoff-Borg, Jesper

2009-01-01

324

BAYESIAN ALIGNMENT OF SIMILARITY SHAPES  

PubMed Central

We develop a Bayesian model for the alignment of two point configurations under the full similarity transformations of rotation, translation and scaling. Other work in this area has concentrated on rigid body transformations, where scale information is preserved, motivated by problems involving molecular data; this is known as form analysis. We concentrate on a Bayesian formulation for statistical shape analysis. We generalize the model introduced by Green and Mardia for the pairwise alignment of two unlabeled configurations to full similarity transformations by introducing a scaling factor to the model. The generalization is not straight-forward, since the model needs to be reformulated to give good performance when scaling is included. We illustrate our method on the alignment of rat growth profiles and a novel application to the alignment of protein domains. Here, scaling is applied to secondary structure elements when comparing protein folds; additionally, we find that one global scaling factor is not in general sufficient to model these data and, hence, we develop a model in which multiple scale factors can be included to handle different scalings of shape components. PMID:24052809

Mardia, Kanti V.; Fallaize, Christopher J.; Barber, Stuart; Jackson, Richard M.; Theobald, Douglas L.

2013-01-01

325

Hydromechanics Laboratory  

Microsoft Academic Search

The Hydromechanics Laboratory supports midshipmen education, as well as midshipmen, faculty and staff research, in the areas of naval architecture and ocean engineering. The laboratory facilities include a large towing tank (380-ft long, 26- ft wide, and 16-ft deep), a small towing tank (120-ft long, 8-ft wide, and 5-ft deep), a coastal engineering wave basin (52-ft long, 48-ft wide, and

David L. Kriebel

326

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

327

Do variables that affect similar bistable apparent-movement displays result in similar changes in perception?  

PubMed

Two bistable apparent-movement displays (i.e. ones that generate two qualitatively different kinds of movement percepts under different conditions) were compared. They were designed to be as similar as possible spatially, and were studied with identical stimulus manipulations to see whether changes in balance between their bistable percepts would be similar. Results show that the two displays had different response characteristics to the same stimulus manipulations. Two models of motion perception that have previously predicted at least one kind of bistable apparent motion were considered in terms of how well they address the current data. As yet, neither model has been shown to predict the motion states and bistable behavior of the two displays studied here. It is concluded that results of the type described here (specifically, differences in the psychophysical functions yielded by two structurally similar but qualitatively different bistable displays) present a challenge for theories of motion perception. PMID:12696857

Petersik, J Timothy; Schellinger, Aura R; Geiger, Sadie L

2003-01-01

328

When is Chemical Similarity Significant? The Statistical Distribution of Chemical Similarity Scores and Its Extreme Values  

PubMed Central

As repositories of chemical molecules continue to expand and become more open, it becomes increasingly important to develop tools to search them efficiently and assess the statistical significance of chemical similarity scores. Here we develop a general framework for understanding, modeling, predicting, and approximating the distribution of chemical similarity scores and its extreme values in large databases. The framework can be applied to different chemical representations and similarity measures but is demonstrated here using the most common binary fingerprints with the Tanimoto similarity measure. After introducing several probabilistic models of fingerprints, including the Conditional Gaussian Uniform model, we show that the distribution of Tanimoto scores can be approximated by the distribution of the ratio of two correlated Normal random variables associated with the corresponding unions and intersections. This remains true also when the distribution of similarity scores is conditioned on the size of the query molecules in order to derive more fine-grained results and improve chemical retrieval. The corresponding extreme value distributions for the maximum scores are approximated by Weibull distributions. From these various distributions and their analytical forms, Z-scores, E-values, and p-values are derived to assess the significance of similarity scores. In addition, the framework allows one to predict also the value of standard chemical retrieval metrics, such as Sensitivity and Specificity at fixed thresholds, or ROC (Receiver Operating Characteristic) curves at multiple thresholds, and to detect outliers in the form of atypical molecules. Numerous and diverse experiments carried in part with large sets of molecules from the ChemDB show remarkable agreement between theory and empirical results. PMID:20540577

Baldi, Pierre

2010-01-01

329

Reproduction of natural corrosion by accelerated laboratory testing methods  

SciTech Connect

Various laboratory corrosion tests have been developed to study the behavior of glass waste forms under conditions similar to those expected in an engineered repository. The data generated by laboratory experiments are useful for understanding corrosion mechanisms and for developing chemical models to predict the long-term behavior of glass. However, it is challenging to demonstrate that these test methods produce results that can be directly related to projecting the behavior of glass waste forms over time periods of thousands of years. One method to build confidence in the applicability of the test methods is to study the natural processes that have been taking place over very long periods in environments similar to those of the repository. In this paper, we discuss whether accelerated testing methods alter the fundamental mechanisms of glass corrosion by comparing the alteration patterns that occur in naturally altered glasses with those that occur in accelerated laboratory environments. This comparison is done by (1) describing the alteration of glasses reacted in nature over long periods of time and in accelerated laboratory environments and (2) establishing the reaction kinetics of naturally altered glass and laboratory reacted glass waste forms.

Luo, J.S.; Wronkiewicz, D.J.; Mazer, J.J.; Bates, J.K.

1996-05-01

330

FLUE GAS CONDITIONING  

EPA Science Inventory

The report gives results of a survey of available flue gas conditioning agents and user experience. Many existing chemicals have been used as conditioning agents in power plants or have been studied in the laboratory as potential agents. The particle collection efficiency of an e...

331

A new airway device for small laboratory animals.  

PubMed

There is a need for a device for improved management of the airway of small laboratory animals during general anaesthesia. This report introduces such a device, referred to here as the airway device (AD). The AD has some similarity to the laryngeal mask airway (LMA) developed for human patients, but the mask portion of the device is specifically designed for small laboratory animals. In addition, the device has an oesophageal extension and unlike the LMA does not have a cuff associated with the mask. This report also shares experience of tests of one prototype AD with six New Zealand white rabbits. The AD was used for administering isoflurane and its effectiveness was evaluated during conditions of spontaneous and controlled intermittent positive pressure ventilation. The results provide encouragement for further development of the AD for airway management of small laboratory animals. PMID:15703132

Imai, A; Eisele, P H; Steffey, E P

2005-01-01

332

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

2009-01-15

333

Self-similarity of the plasma edge fluctuations B. A. Carreras  

E-print Network

Self-similarity of the plasma edge fluctuations B. A. Carreras Oak Ridge National Laboratory, Oak, stellarators, and reversed-field pinch. The results reveal the self-similar character of the electrostatic fluctuations at the plasma edge with self-similarity parameters ranging from 0.62 to 0.72. These results show

van Milligen, Boudewijn

334

Self-similarity of the plasma edge fluctuations B. A. Carreras  

E-print Network

Self-similarity of the plasma edge fluctuations B. A. Carreras Oak Ridge National Laboratory, Oak devices such as tokamaks, stellarators, and reversed-field pinch. The results reveal the self-similar character of the electrostatic fluctuations at the plasma edge with self-similarity parameters ranging from

Newman, David

335

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

336

Imprecision and Structure in Modelling Subjective Similarity  

NASA Astrophysics Data System (ADS)

Similarity measures based on feature matching have been designed for modelling subjective similarity judgements. In this paper, the taxonomic presence-absence feature representation is extended to assess the similarity of objects whose attributes are described by partial satisfaction of predicates or by fuzzy sets. The principle of minimum specificity is used to obtain possibilistic bounds on the combination of similarity assessments. A priority hierarchy and bipolarity are incorporated into similarity measurement to utilize inter-attribute relationships in modelling similarity judgements.

Sudkamp, Thomas

337

Laboratory accreditation  

SciTech Connect

Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

Pettit, R.B.

1998-08-01

338

Cross-reactivity of steroid hormone immunoassays: clinical significance and two-dimensional molecular similarity prediction  

PubMed Central

Background Immunoassays are widely used in clinical laboratories for measurement of plasma/serum concentrations of steroid hormones such as cortisol and testosterone. Immunoassays can be performed on a variety of standard clinical chemistry analyzers, thus allowing even small clinical laboratories to do analysis on-site. One limitation of steroid hormone immunoassays is interference caused by compounds with structural similarity to the target steroid of the assay. Interfering molecules include structurally related endogenous compounds and their metabolites as well as drugs such as anabolic steroids and synthetic glucocorticoids. Methods Cross-reactivity of a structurally diverse set of compounds were determined for the Roche Diagnostics Elecsys assays for cortisol, dehydroepiandrosterone (DHEA) sulfate, estradiol, progesterone, and testosterone. These data were compared and contrasted to package insert data and published cross-reactivity studies for other marketed steroid hormone immunoassays. Cross-reactivity was computationally predicted using the technique of two-dimensional molecular similarity. Results The Roche Elecsys Cortisol and Testosterone II assays showed a wider range of cross-reactivity than the DHEA sulfate, Estradiol II, and Progesterone II assays. 6-Methylprednisolone and prednisolone showed high cross-reactivity for the cortisol assay, with high likelihood of clinically significant effect for patients administered these drugs. In addition, 21-deoxycortisol likely produces clinically relevant cross-reactivity for cortisol in patients with 21-hydroxylase deficiency, while 11-deoxycortisol may produce clinically relevant cross-reactivity in 11?-hydroxylase deficiency or following metyrapone challenge. Several anabolic steroids may produce clinically significant false positives on the testosterone assay, although interpretation is limited by sparse pharmacokinetic data for some of these drugs. Norethindrone therapy may impact immunoassay measurement of testosterone in women. Using two-dimensional similarity calculations, all compounds with high cross-reactivity also showed a high degree of similarity to the target molecule of the immunoassay. Conclusions Compounds producing cross-reactivity in steroid hormone immunoassays generally have a high degree of structural similarity to the target hormone. Clinically significant interactions can occur with structurally similar drugs (e.g., prednisolone and cortisol immunoassays; methyltestosterone and testosterone immunoassays) or with endogenous compounds such as 21-deoxycortisol that can accumulate to very high concentrations in certain disease conditions. Simple similarity calculations can help triage compounds for future testing of assay cross-reactivity. PMID:25071417

2014-01-01

339

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

Microsoft Academic Search

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

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

1983-01-01

340

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

341

Archimedes Laboratory  

NSDL National Science Digital Library

Proving that geometry can be more fun than a barrel of monkeys, Archimedes Laboratory is "an 'intuitive' puzzle site with fewer formulas and more visuals, which may encourage students learning this science or just constitute a platform for reflection." Probably the most strictly educational section of the site is Math to Discover, which contains discussions of the history of numbers and mathematical patterns, to name a few. Also of interest are the Puzzles to Make and Puzzles to Solve sections. Visitors can follow online instructions to create geometrical curiosities or browse a small selection of impossible object images.

342

Neuromuscular fatigue following isometric contractions with similar torque time integral.  

PubMed

Torque time integral (TTI) is the combination of intensity and duration of a contraction. The aim of this study was to compare neuromuscular alterations following different isometric sub-maximal contractions of the knee extensor muscles but with similar TTI. Sixteen participants performed 3 sustained contractions at different intensities (25%, 50%, and 75% of Maximal Voluntary Contraction (MVC) torque) with different durations (68.5±33.4?s, 35.1±16.8?s and 24.8±12.9?s, respectively) but similar TTI value. MVC torque, maximal voluntary activation level (VAL), M-wave characteristics and potentiated doublet amplitude were assessed before and immediately after the sustained contractions. EMG activity of the vastus lateralis (VL) and -rectus femoris (RF) muscles was recorded during the sustained contractions. MVC torque reduction was similar in the 3 conditions after the exercise (-23.4±2.7%). VAL decreased significantly in a similar extent (-3.1±1.3%) after the 3 sustained contractions. Potentiated doublet amplitude was similarly reduced in the 3 conditions (-19.7±1.5%), but VL and RF M-wave amplitudes remained unchanged. EMG activity of VL and RF muscles increased in the same extent during the 3 contractions (VL: 54.5±40.4%; RF: 53.1±48.7%). These results suggest that central and peripheral alterations accounting for muscle fatigue are similar following isometric contractions with similar TTI. TTI should be considered in the exploration of muscle fatigue during sustained isometric contractions. PMID:25285471

Rozand, V; Cattagni, T; Theurel, J; Martin, A; Lepers, R

2015-01-01

343

Laboratory Performance Testing of Residential Dehumidifiers (Presentation)  

SciTech Connect

Six residential vapor compression cycle dehumidifiers spanning the available range of capacities and efficiencies were tested in the National Renewable Energy Laboratory's Heating, Ventilating, and Air-Conditioning Systems Laboratory. Each was tested under a wide range of indoor air conditions to facilitate the development of performance curves for use in whole-building simulation tools.

Winkler, J.

2012-03-01

344

International standards in laboratory medicine  

Microsoft Academic Search

International standards play an important role in establishing quality systems. A considerable number of standards have been created by ISO and CEN for medical laboratories. Standards can be looked upon in a hierarchal manner but most standards are produced in similarly with iterative consultations and review by the intended users. Most standards are suggested by industry and national or international

Anders Kallner

2001-01-01

345

Collisionless laboratory astrophysics with lasers  

Microsoft Academic Search

Possibilities of laboratory simulation of various explosive phenomena in space and cosmic plasmas with magnetic fields are analyzed on the bases of similarity criteria, properties of collisionless interactions, and parameters of laser-produced plasmas. It is shown how the physics of such widely different phenomena as barium releases in Earth's magnetosphere, collisionless deceleration of supernova remnants, and related shock-wave generation in

Yuri P. Zakharov

2003-01-01

346

Modeling Laboratory Plasmas with Smoothed Particle Hydrodynamics  

NASA Astrophysics Data System (ADS)

Smoothed Particle Hydrodynamics (SPH) [1], a mesh-free Lagrangian method long used to study astrophysical systems, is increasingly used to study more terrestrial applications in engineering. Here we present results of simulations of plasmas created in the laboratory calculated using a variant of Smoothed Particle Magnetohydrodynamics (SPMHD) [2] to treat the equations of resistive magnetohydrodynamics. We discuss the challenges posed by boundary conditions and the treatment of fields in a vacuum; we then describe simple test problems used to demonstrate how the method handles these challenges. Finally, we show the results of a calculation modeling the acceleration of a plasma with electric currents similar to those created in the Compact Toroid Injection Experiment (CTIX) [3]. References: [1] J. J. Monaghan, Ann. Rev. Astron. Astrophys. 30, 543 (1992) [2] D. J. Price, J. J. Monaghan, MNRAS 348, 139 (2004) [3] K. L. Baker et al, Nucl. Fusion, 42, 94 (2002)

Johnson, Jeffrey; Owen, Michael

2008-11-01

347

Classical Conditioning  

NSDL National Science Digital Library

!!Classical Conditioning!! Classical conditioning is the use of Pavlovian conditioning procedures where a neutral stimulus becomes capable of evoking a response through pairing with an unconditioned stimulus. Click the link below to get an introduction into classical conditioning. Introduction to Classical Conditioning Now that you\\'ve been introduced to classical conditioning, view the clip at the link below, ...

Mrs. Palacios, Miss Miller, Mr. Rowser

2008-04-01

348

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.

349

Biosequence Similarity Search on the Mercury System  

E-print Network

Biosequence Similarity Search on the Mercury System Praveen Krishnamurthy, Jeremy Buhler, Roger Chamberlain, Mark Franklin, Kwame Gyang, and Joseph Lancaster, "Biosequence Similarity Search on the Mercury on the Mercury System Praveen Krishnamurthy, Jeremy Buhler, Roger Chamberlain, Mark Franklin, Kwame Gyang

Chamberlain, Roger

350

Imprecision and Structure in Modelling Subjective Similarity  

Microsoft Academic Search

Similarity measures based on feature matching have been designed for modelling subjective similarity judgements. In this paper,\\u000a the taxonomic presence-absence feature representation is extended to assess the similarity of objects whose attributes are\\u000a described by partial satisfaction of predicates or by fuzzy sets. The principle of minimum specificity is used to obtain possibilistic\\u000a bounds on the combination of similarity assessments.

Thomas Sudkamp

2008-01-01

351

Distances and Similarities of Saturated Computational Verbs  

Microsoft Academic Search

The distance and similarity between two computa- tional verbs are very important to many applications involving the comparison of computational verbs. For example, in computa- tional verb inferences, the similarities among computational verbs decide the firing levels of computational verb rules. In this paper, the comprehensive definitions of verb distance and similarity were given based on the saturated evolving functions

Tao Yang

2006-01-01

352

Impact of Similarity Measures on Webpage Clustering  

Microsoft Academic Search

Clustering of web documents enables (semi-)automatedcategorization, and facilitates certain types of search.Any clustering method has to embed the documentsin a suitable similarity space. While several clusteringmethods and the associated similarity measures havebeen proposed in the past, there is no systematic comparativestudy of the impact of similarity metrics oncluster quality, possibly because the popular cost criteriado not readily translate across qualitatively

Er Strehl; Joydeep Ghosh; Raymond Mooney

2000-01-01

353

Phonetic alignment and similarity Grzegorz Kondrak  

E-print Network

Phonetic alignment and similarity Grzegorz Kondrak Department of Computing Science University@cs.ualberta.ca April 4, 2003 Abstract. The computation of the optimal phonetic alignment and the phonetic similarity be that employs a scoring scheme for computing phonetic similarity between phonetic segments on the basis

Kondrak, Greg

354

Music Similarity Measures: What's the use?  

Microsoft Academic Search

Electronic Music Distribution (EMD) is in demand of robust, automatically extracted music descriptors. We introduce a timbral similarity measures for comparing music titles. This measure is based on a Gaussian model of cepstrum coefficients. We describe the timbre extractor and the corresponding timbral similarity relation. We describe experiments in assessing the quality of the similarity relation, and show that the

Jean-julien Aucouturier; François Pachet

2002-01-01

355

Optimal Invariant Similar Tests for Instrumental Variables Regression  

Microsoft Academic Search

This paper considers tests of the parameter on endogenous variables in an instrumental variables regression model. The focus is on determining tests that have certain optimal power properties. We start by considering a model with normally distributed errors and known error covariance matrix. We consider tests that are similar and satisfy a natural rotational invariance condition. We determine tests that

Donald W. K. Andrews; Marcelo Moreira; James H. Stock

2005-01-01

356

Auditory Attention to Space and Frequency Activates Similar Cerebral Systems  

Microsoft Academic Search

PET was used to test the hypothesis that similar neural systems are involved in attending to spectral and to spatial features of sounds. In each of four conditions subjects heard tones varying randomly in frequency and location and responded to either the low- or the high-frequency stimuli, ignoring location, or to stimuli on the left or right, ignoring frequency. In

Robert J. Zatorre; Todd A. Mondor; Alan C. Evans

1999-01-01

357

Diesel Exhaust Is Not a Pulmonary Carcinogen in CD1 Mice Exposed under Conditions Carcinogenic to F344 Rats  

Microsoft Academic Search

Differences among laboratory animal species in the pulmonary carcinogenicity of chronic inhalation exposure to diesel exhaust have raised several important interpretive issues. Under similar heavy exposure conditions, it is clear that diesel exhaust is a pulmonary carcinogen in rats, but not in Syrian hamsters. Previous reports give conflicting views of the response of mice, which is presently considered equivocal. This

Joe L. Mauderly; Deborah A. Banas; William C. Griffith; Fletcher F. Hahn; Rogene F. Henderson; ROGER O. MCCLELLANJ

1996-01-01

358

Enlarged similarity of nucleic acid sequences.  

PubMed

The concept of nucleic acid sequence base alternations is presented. The number of base alterations for the sequences of different length is established. The definition of "enlarged similarity" of nucleic acids sequences on the basis of sequence base alterations is introduced. Mutual information between sequences is used as a quantitative measure of enlarged similarity for two compared sequences. The method of mutual information calculation is developed considering the correlation of bases in compared sequences. The definitions of correlated similarity and evolution similarity between compared sequences are given. Results of the use of enlarged similarity approach for DNA sequences analysis are discussed. PMID:8905233

Korotkov, E V; Korotkova, M A

1996-06-30

359

A Laboratory Prototype and Simulation of Ground Constant Measurement of Circuit Breaker  

NASA Astrophysics Data System (ADS)

This paper presents a new method of finding ground constant of circuit breaker in the power system laboratory. Experimental set up has been implemented in a laboratory environment and results are found to be satisfactory. The proposed set up in the laboratory has been conceived, designed and implemented through senior design project, which leads to a very innovative design, similar to an actual circuit breaker in the transmission line. This gives the students, who subsequently performed the experiments as a part of their coursework, a real life feel of a power system. The proposed set up has been tested for different fault conditions along with various neutral and grounding system conditions. Also, a simulation of the proposed set up has been carried out in MATLAB environment. At the end, a comparative evaluation has been done on both the practical and the simulated results. It has been observed that practical value closely matches with the simulation results.

Shah, A. M.; Bhalja, B. R.

2014-07-01

360

The snowmaker: nature identical snow production in the laboratory  

NASA Astrophysics Data System (ADS)

Using natural snow for laboratory experiments can be tricky due to shortage of winter periods and snowfall, difficulties of sample casting and transport, and the great variability of natural snow due to the varying conditions of crystal growth in the clouds. This hinders repeatable laboratory experiments with reproducible specimen and microstructural characteristics. To minimize experimental uncertainties we designed an improved machine called snowmaker, which enables us to produce nature-identical snow in a cold laboratory under well defined conditions. The snowmaker is based on well-known principles: warm humid air from a heated water basin is advected into a cold nucleation chamber where the vapor resublimates on stretched Nylon wires. Crystals are automatically harvested by a motor driven brush rack and collected in a box, thereby several kilograms of snow can be produced per day with minimum maintenance. The excess vapor is collected in a moisture trap to avoid frost in the laboratory. The entire construction is designed as a rolling, modular assembly system which can easily carried out of the laboratory for defrosting. In addition to previous attempts we focus on the reproducibility of the samples and the comparison to natural snow down to the microscale. We show that the settings of water temperature and cold laboratory temperature facilitates the production of different crystal shapes like dendrites and needles in a reproducible way. Besides photography, we analyzed the microstructure of snowmaker crystals in aggregated specimen by X-ray microtomography. Depending on the settings we can create reproducible samples with density of 50-170 kg/m3 and specific surface areas of 50-80 mm-1. We briefly touch similarities between artificial and natural snow samples with respect to crystal habit, microstructural parameters and short-time metamorphism.

Schleef, S.; Jaggi, M.; Loewe, H.; Schneebeli, M.

2013-12-01

361

Using Reaction Mechanism to Measure Enzyme Similarity  

PubMed Central

Summary The concept of reaction similarity has been well-studied in terms of the overall transformation associated with a reaction, but not in terms of mechanism. We present the first method to give a quantitative measure of the similarity of reactions based upon their explicit mechanisms. Two approaches are presented to measure the similarity between individual steps of mechanisms: a fingerprint-based approach which incorporates relevant information on each mechanistic step, and an approach based only on bond formation, cleavage and changes in order. The overall similarity for two reaction mechanisms is then calculated using the Needleman-Wunsch alignment algorithm. An analysis of MACiE, a database of enzyme mechanisms, using our measure of similarity identifies some examples of convergent evolution of chemical mechanism. In many cases mechanism similarity is not reflected by similarity according to the EC system of enzyme classification. In particular, little mechanistic information is conveyed by the class level of the EC. PMID:17400244

O’Boyle, Noel M.; Holliday, Gemma L.; Almonacid, Daniel E.; Mitchell, John B.O.

2012-01-01

362

Laboratory prototype flash evaporator  

NASA Technical Reports Server (NTRS)

A laboratory prototype flash evaporator that is being developed as a candidate for the space shuttle environmental control system expendable heat sink is described. The single evaporator configuration uses water as an evaporant to accommodate reentry and on-orbit peak heat loads, and Freon 22 for terrestrial flight phases below 120,000 feet altitude. The design features, fabrication techniques used for the prototype unit, redundancy considerations, and the fluid temperature control arrangement are reported in detail. The results of an extensive test program to determine the evaporator operational characteristics under a wide variety of conditions are presented.

Gaddis, J. L.

1972-01-01

363

Regularities in transient modes in the seismic process according to the laboratory and natural modeling  

Microsoft Academic Search

Regularities in the excitation and relaxation of rock failure were revealed in a series of laboratory experiments. Similar\\u000a regularities are found also in natural conditions. A physical idea and its mathematical description are suggested for explaining\\u000a the obtained experimental data. The aim of the experiments was to understand the character of excitation of the failure, triggered\\u000a by the external impact,

V. B. Smirnov; A. V. Ponomarev; P. Benard; A. V. Patonin

2010-01-01

364

Metallic wear debris sensors: promising developments in failure prevention for wind turbine gearsets and similar components  

NASA Astrophysics Data System (ADS)

Wind turbines are frequently located in remote, hard-to-reach locations, making it difficult to apply traditional oil analysis sampling of the machine's critical gearset at timely intervals. Metal detection sensors are excellent candidates for sensors designed to monitor machine condition in vivo. Remotely sited components, such as wind turbines, therefore, can be comfortably monitored from a distance. Online sensor technology has come of age with products now capable of identifying onset of wear in time to avoid or mitigate failure. Online oil analysis is now viable, and can be integrated with onsite testing to vet sensor alarms, as well as traditional oil analysis, as furnished by offsite laboratories. Controlled laboratory research data were gathered from tests conducted on a typical wind turbine gearbox, wherein total ferrous particle measurement and metallic particle counting were employed and monitored. The results were then compared with a physical inspection for wear experienced by the gearset. The efficacy of results discussed herein strongly suggests the viability of metallic wear debris sensors in today's wind turbine gearsets, as correlation between sensor data and machine trauma were very good. By extension, similar components and settings would also seem amenable to wear particle sensor monitoring. To our knowledge no experiments such as described herein, have previously been conducted and published.

Poley, Jack; Dines, Michael

2011-04-01

365

THE OCCURRENCE IN VIRGINIA OF GREEN.GILLED OYSTERS SIMILAR TO THOSE OF MARENNES  

E-print Network

THE OCCURRENCE IN VIRGINIA OF GREEN.GILLED OYSTERS SIMILAR TO THOSE OF MARENNES By Philip H IN VIRGINIA OF GREEN.GILLED OYSTERS SIMILAR TO THOSE OF MARENNES. .:/-' By PHILIP H. MITCHELL and RAYMOND L- logical Laboratory of Brown University. INTRODUCTION. The appearance of green-gilled oysters in Lynnhaven

366

Simple Penning ion source for laboratory research and development applications  

NASA Astrophysics Data System (ADS)

A simple Penning ion generator (PIG) that can be easily fabricated with simple machining skills and standard laboratory accessories is described. The PIG source uses an iron cathode body, samarium cobalt permanent magnet, stainless steel anode, and iron cathode faceplate to generate a plasma discharge that yields a continuous 1mA beam of positively charged hydrogen ions at 1mTorr of pressure. This operating condition requires 5.4kV and 32.4W of power. Operation with helium is similar to hydrogen. The ion source is being designed and investigated for use in a sealed-tube neutron generator; however, this ion source is thoroughly described so that it can be easily implemented by other researchers for other laboratory research and development applications.

Rovey, Joshua L.; Ruzic, Brandon P.; Houlahan, Thomas J.

2007-10-01

367

Simple Penning ion source for laboratory research and development applications.  

PubMed

A simple Penning ion generator (PIG) that can be easily fabricated with simple machining skills and standard laboratory accessories is described. The PIG source uses an iron cathode body, samarium cobalt permanent magnet, stainless steel anode, and iron cathode faceplate to generate a plasma discharge that yields a continuous 1 mA beam of positively charged hydrogen ions at 1 mTorr of pressure. This operating condition requires 5.4 kV and 32.4 W of power. Operation with helium is similar to hydrogen. The ion source is being designed and investigated for use in a sealed-tube neutron generator; however, this ion source is thoroughly described so that it can be easily implemented by other researchers for other laboratory research and development applications. PMID:17979457

Rovey, Joshua L; Ruzic, Brandon P; Houlahan, Thomas J

2007-10-01

368

Measuring Similarity Between Dynamic Ensembles of Biomolecules  

PubMed Central

Methods for comparing ensembles of biomolecules assess the population overlap between distributions but fail to fully quantify structural similarity. We present a simple and general approach for quantifying population overlap and structural similarity between ensembles. This approach captures improvements in the quality of ensembles determined using increasing input experimental data that go undetected using conventional methods and reveals unexpected similarities between RNA ensembles determined using NMR and molecular dynamics simulations. PMID:24705474

Yang, Shan; Salmon, Loïc; Al-Hashimi, Hashim M.

2014-01-01

369

42 CFR 493.1210 - Condition: Routine chemistry.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Routine chemistry. 493.1210 Section 493.1210...493.1210 Condition: Routine chemistry. If the laboratory provides services in the subspecialty of Routine chemistry, the laboratory must meet the...

2012-10-01

370

42 CFR 493.1210 - Condition: Routine chemistry.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Routine chemistry. 493.1210 Section 493.1210...493.1210 Condition: Routine chemistry. If the laboratory provides services in the subspecialty of Routine chemistry, the laboratory must meet the...

2013-10-01

371

42 CFR 493.1210 - Condition: Routine chemistry.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Routine chemistry. 493.1210 Section 493.1210...493.1210 Condition: Routine chemistry. If the laboratory provides services in the subspecialty of Routine chemistry, the laboratory must meet the...

2011-10-01

372

42 CFR 493.1210 - Condition: Routine chemistry.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: Routine chemistry. 493.1210 Section 493.1210...493.1210 Condition: Routine chemistry. If the laboratory provides services in the subspecialty of Routine chemistry, the laboratory must meet the...

2014-10-01

373

42 CFR 493.1208 - Condition: General immunology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: General immunology. 493.1208 Section 493...493.1208 Condition: General immunology. If the laboratory provides services in the subspecialty of General immunology, the laboratory must meet the...

2011-10-01

374

42 CFR 493.1208 - Condition: General immunology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: General immunology. 493.1208 Section 493...493.1208 Condition: General immunology. If the laboratory provides services in the subspecialty of General immunology, the laboratory must meet the...

2010-10-01

375

42 CFR 493.1208 - Condition: General immunology.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: General immunology. 493.1208 Section 493...493.1208 Condition: General immunology. If the laboratory provides services in the subspecialty of General immunology, the laboratory must meet the...

2014-10-01

376

42 CFR 493.1208 - Condition: General immunology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: General immunology. 493.1208 Section 493...493.1208 Condition: General immunology. If the laboratory provides services in the subspecialty of General immunology, the laboratory must meet the...

2013-10-01

377

42 CFR 493.1208 - Condition: General immunology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: General immunology. 493.1208 Section 493...493.1208 Condition: General immunology. If the laboratory provides services in the subspecialty of General immunology, the laboratory must meet the...

2012-10-01

378

42 CFR 493.1220 - Condition: Oral pathology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Oral pathology. 493.1220 Section 493.1220... § 493.1220 Condition: Oral pathology. If the laboratory provides services in the subspecialty of Oral pathology, the laboratory must meet the...

2011-10-01

379

42 CFR 493.1220 - Condition: Oral pathology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Oral pathology. 493.1220 Section 493.1220... § 493.1220 Condition: Oral pathology. If the laboratory provides services in the subspecialty of Oral pathology, the laboratory must meet the...

2012-10-01

380

42 CFR 493.1220 - Condition: Oral pathology.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: Oral pathology. 493.1220 Section 493.1220... § 493.1220 Condition: Oral pathology. If the laboratory provides services in the subspecialty of Oral pathology, the laboratory must meet the...

2014-10-01

381

42 CFR 493.1220 - Condition: Oral pathology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Oral pathology. 493.1220 Section 493.1220... § 493.1220 Condition: Oral pathology. If the laboratory provides services in the subspecialty of Oral pathology, the laboratory must meet the...

2013-10-01

382

42 CFR 493.1207 - Condition: Syphilis serology.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Condition: Syphilis serology. 493.1207 Section...Testing § 493.1207 Condition: Syphilis serology. If the laboratory provides services in the subspecialty of Syphilis serology, the laboratory must...

2014-10-01

383

42 CFR 493.1207 - Condition: Syphilis serology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Syphilis serology. 493.1207 Section...Testing § 493.1207 Condition: Syphilis serology. If the laboratory provides services in the subspecialty of Syphilis serology, the laboratory must...

2013-10-01

384

42 CFR 493.1207 - Condition: Syphilis serology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Syphilis serology. 493.1207 Section...Testing § 493.1207 Condition: Syphilis serology. If the laboratory provides services in the subspecialty of Syphilis serology, the laboratory must...

2011-10-01

385

42 CFR 493.1207 - Condition: Syphilis serology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Syphilis serology. 493.1207 Section...Testing § 493.1207 Condition: Syphilis serology. If the laboratory provides services in the subspecialty of Syphilis serology, the laboratory must...

2010-10-01

386

42 CFR 493.1207 - Condition: Syphilis serology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Syphilis serology. 493.1207 Section...Testing § 493.1207 Condition: Syphilis serology. If the laboratory provides services in the subspecialty of Syphilis serology, the laboratory must...

2012-10-01

387

[Designing a clinical microbiology laboratory].  

PubMed

The microbiology laboratory should be a safe, efficient, and comfortable place for those working there, and a pleasant place for visitors. According to the ISO 15189 standard, it should be spacious enough for the workload to be carried out without jeopardizing quality or the safety of the persons present, whether workers or visitors, and provide optimal comfort to all occupants. In addition, the setup should respect the privacy of patients, and provide controlled access to the different laboratory areas and a safe place for storing clinical samples, manuals, and reagents. In the design of the facilities, the needs of specialists, technicians, and other personnel must converge, without forgetting patients, their relatives, and other visitors. The clinical microbiology laboratory has certain characteristics that make it different from other diagnostic laboratories. Its main activity involves isolation, propagation, and handling of pathogenic microorganisms that pose a risk to the laboratory personnel. To minimize this risk, the laboratory must meet a certain level of biosafety. Moreover, correct interpretation of microbiological cultures depends on the capacity of the laboratory to avoid or minimize the presence of contaminants; hence, proper handling of samples and cultures (aseptic conditions, biosafety cabinet) is mandatory. A number of documents and regulations, from very general to highly specific (biosafety), affect the design of the microbiology laboratory. The aim of this report is to establish the minimum requirements and recommendations for designing clinical microbiology laboratories, based on a review of current regulations. It is contemplated as an aid to microbiology specialists who are designing or planning to reform their laboratories. PMID:19740573

Alados, Juan Carlos; Alcaraz, María Jesús; Aller, Ana Isabel; Miranda, Consuelo; Pérez, José Luis; Romero, Patricia A

2010-01-01

388

Inquiring Scaffolds in Laboratory Tasks: An Instance of a "Worked Laboratory Guide Effect"?  

ERIC Educational Resources Information Center

The study explores if established support devices for paper-pencil problem solving, namely worked examples and incremental scaffolds, are applicable to laboratory tasks. N?=?173 grade eight students solved in dyads a physics laboratory task in one of three conditions. In condition A (unguided problem solving), students were asked to determine the…

Schmidt-Borcherding, Florian; Hänze, Martin; Wodzinski, Rita; Rincke, Karsten

2013-01-01

389

Experimental observations of self-similar plasma expansion  

NASA Technical Reports Server (NTRS)

The present investigation is concerned with measurements of the plasma potential profile of an expanding plasma, taking into account the demonstration of the self-similar behavior of such a plasma. The obtained experimental results are consistent with self-similar solutions reported by Crow et al. (1975). It is found that the quasi-neutrality condition breaks down early during the experiment. A consideration of the effect of charge separation is, therefore, required. Attention is given to the evolution of the potential profiles of the expanding plasma as a function of time, the accelerated ion fronts, and the sheath formation of the expanding plasma into a floating boundary.

Chan, C.; Hershkowitz, N.; Ferreira, A.; Intrator, T.; Nelson, B.; Lonngren, K.

1984-01-01

390

Similar mandibular osseous lesions in Tyrannosaurus rex and man.  

PubMed

This report identifies several cases of similar-appearing multiple lesions in the mandibles of both humans and the dinosaur Tyrannosaurus rex (T. rex). A diagnosis and potential etiologies are discussed. The appearance of these lesions in prehistoric fossils suggests that this pathology is an ancient affliction which predates humans and our mammalian ancestors. Lytic lesions of the oral structures have occurred in man and higher animals throughout time. The causes range from congenital anomalies, trauma, and infections to benign and metastatic neoplasms. Not only mammals suffer from these conditions; reptiles and birds experience similar diseases. PMID:16350345

Neiburger, E J

2005-01-01

391

Self-Similar Collapse of n Point Vortices  

NASA Astrophysics Data System (ADS)

A system of a finite number of linear vortices in self-similar motion and under suitable conditions that are related to the initial positions and circulations of the vortices can collapse to the point with finite time. It is shown how the initial positions that lead to the collapse can be found numerically. An explicit solution for the self-similar collapse of the trajectories is derived. Examples of a collapsing system of 3, 7, and 30 vortices are given. A description is given of how to obtain the curves of collapsing positions of vortices if one particular system of vortices has already been found. Examples of such curves are given.

Kudela, Henryk

2014-10-01

392

LABORATORY I FORCES AND EQUILIBRIUM  

E-print Network

LABORATORY I FORCES AND EQUILIBRIUM Lab I -1 In biological systems, most objects of interest are in or almost in equilibrium, either stationary or moving with a constant velocity. This important condition of equilibrium is the result of a balance among all of the different forces interacting with the object

Minnesota, University of

393

Does organisation by similarity assist image browsing?  

Microsoft Academic Search

In current systems for browsing image collections, users are presented with sets of thumbnail images arranged in some default order on the screen. We are investigating whether it benefits users to have sets of thumbnails arranged according to their mutual similarity, so images that are alike are placed together. There are, of course, many possible definitions of “similarity”: so far

Kerry Rodden; Wojciech Basalaj; David Sinclair; Kenneth R. Wood

2001-01-01

394

Hamming Embedding Similarity-based Image Classification  

E-print Network

Hamming Embedding Similarity-based Image Classification Mihir Jain INRIA Rennes mihir classification frame- work based on patch matching. More precisely, we adapt the Hamming Embedding technique the scores output by the Ham- ming Embedding matching technique into a proper similar- ity space. Comparative

Paris-Sud XI, Université de

395

Self-Similar Measures for Quasicrystals  

Microsoft Academic Search

We study self-similar measures of Hutchinson type, defined by compact families of contractions, both in a single and multi-component setting. The results are applied in the context of general model sets to infer, via a generalized version of Weyl's Theorem on uniform distribution, the existence of invariant measures for families of self-similarities of regular model sets.

Michael Baake; Robert V. Moody

2000-01-01

396

Similarities and distances in fuzzy regression modeling  

Microsoft Academic Search

Abstract We study the set of the solutions of a fuzzy regression model as a metric space. For each metric, we define a similarity ratio in order to compare,the spaces of solutions of a fuzzy regression model. We prove that the similarity ratios, that can be extracted from these different metrics, are all the same as in [4]. As an

Basil K. Papadopoulos; M. A. Sirpi

2004-01-01

397

Unsupervised Feature Selection Using Feature Similarity  

Microsoft Academic Search

In this article, we describe an unsupervised feature selection algorithm suitable for data sets, large in both dimension and size. The method is based on measuring similarity between features whereby redundancy therein is removed. This does not need any search and, therefore, is fast. A new feature similarity measure, called maximum information compression index, is introduced. The algorithm is generic

Pabitra Mitra; C. A. Murthy; Sankar K. Pal

2002-01-01

398

Searching for Self-Similarity in GPRS  

Microsoft Academic Search

Based on measurements in live GPRS networks, the degree of self- similarity for the aggregated WAP and WEB traffic is investigated by utilizing six well established Hurst parameter estimators. We show that in particular WAP traffic is long-range dependent and its scaling for time scales below the average page duration is not second order self similar. WAP over UDP can

Roger Kalden; Sami Ibrahim

2004-01-01

399

Non-Hermitian Hamiltonians and similarity transformations  

E-print Network

We show that a straightforward similarity transformation between an Hermitian operator and a non-Hermitian one enables one to prove the results obtained by other authors by means of a gauge-like transformation. The similarity transformation also reveals the connection with pseudo-Hermiticity

Francisco M. Fernández

2015-02-04

400

Searching Similar Modules in Protein Interaction Networks  

Microsoft Academic Search

We developed a new method to search protein networks functionally similar to a given query signal transduction pathway within protein interaction networks. This method consists of two parts: 1) a backtracking search algorithm to find topologically identical subgraphs and 2) a measurement of similarity between proteins by using Gene Ontology (1). For validation of our method, we implemented a software

Hiroyuki Ok; Masanori Arit

401

Fingerprint Matching Based on Global Comprehensive Similarity  

E-print Network

Fingerprint Matching Based on Global Comprehensive Similarity Yuliang He, Jie Tian, Senior Member in the representation of a fingerprint. Finally, we model the relationship between transformation and the comprehensive similarity between two fingerprints in terms of histogram for initial parameter estimation. Through

Tian, Jie

402

On similarity in the atmospheric boundary layer  

Microsoft Academic Search

A similarity theory for the atmospheric boundary layer is presented. The Monin-Obukhov similarity theory for the surface layer is a particular case of this new theory, for the case of z ? 0. Universal functions which are in agreement with empirical data are obtained for the stable and convective regimes.

Zbigniew Sorbjan

1986-01-01

403

Similarity indices, sample size and diversity  

Microsoft Academic Search

The effect of sample size and species diversity on a variety of similarity indices is explored. Real values of a similarity index must be evaluated relative to the expected maximum value of that index, which is the value obtained for samples randomly drawn from the same universe, with the diversity and sample sizes of the real samples. It is shown

Henk Wolda

1981-01-01

404

Predicting similarity and categorization from identification  

Microsoft Academic Search

In this article, the relation between the identification, similarity judgment, and categorization of multidimensional perceptual stimuli is studied. The theoretical analysis focused on general recognition theory (CRT), which is a multidimensional generalization of signal detection theory. In one application, 2 Ss first identified a set of confusable stimuli and then made judgments of their painvise similarity. The second application was

F. Gregory Ashby; W. William Lee

1991-01-01

405

Manipula math with Java : similar figures  

NSDL National Science Digital Library

Teachers can use this applet to give a visual demonstration of the idea of similar triangles or transformations. The applet could be used in whole class demonstrations to introduce the topic or provide varied examples of how different similar triangles can be.

IES, Inc

2003-01-01

406

Extreme Conditions Modeling Workshop Report  

SciTech Connect

Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

2014-07-01

407

When Is a Laboratory a Laboratory?  

ERIC Educational Resources Information Center

Gives advice on the legal necessity of safety planning for school science (or other) laboratories. Recommends looking into governmental definitions of the term "laboratory" to determine which educational activities should be covered by safety planning. (WRM)

Roy, Ken

1999-01-01

408

Laboratory simulations of Mars evaporite geochemistry  

Microsoft Academic Search

Evaporite-rich sedimentary deposits on Mars were formed under chemical conditions quite different from those on the Earth. Their unique chemistries record the chemical and aqueous conditions under which they were formed and possibly subsequent conditions to which they were subjected. We have produced evaporite salt mineral suites in the laboratory under two simulated Martian atmospheres: (1) present-day and (2) a

Jeffrey M. Moore; Mark A. Bullock; Horton Newsom; Melissa Nelson

2010-01-01

409

Comparison of Profile Similarity Measures for Genetic Interaction Networks  

PubMed Central

Analysis of genetic interaction networks often involves identifying genes with similar profiles, which is typically indicative of a common function. While several profile similarity measures have been applied in this context, they have never been systematically benchmarked. We compared a diverse set of correlation measures, including measures commonly used by the genetic interaction community as well as several other candidate measures, by assessing their utility in extracting functional information from genetic interaction data. We find that the dot product, one of the simplest vector operations, outperforms most other measures over a large range of gene pairs. More generally, linear similarity measures such as the dot product, Pearson correlation or cosine similarity perform better than set overlap measures such as Jaccard coefficient. Similarity measures that involve L2-normalization of the profiles tend to perform better for the top-most similar pairs but perform less favorably when a larger set of gene pairs is considered or when the genetic interaction data is thresholded. Such measures are also less robust to the presence of noise and batch effects in the genetic interaction data. Overall, the dot product measure performs consistently among the best measures under a variety of different conditions and genetic interaction datasets. PMID:23874711

Deshpande, Raamesh; VanderSluis, Benjamin; Myers, Chad L.

2013-01-01

410

Looking for Similarities Between Lowland (Flash) Floods  

NASA Astrophysics Data System (ADS)

On 26 August 2010 the eastern part of The Netherlands and the bordering part of Germany were struck by a series of rainfall events. Over an area of 740 km2 more than 120 mm of rainfall were observed in 24 h. We investigated the unprecedented flash flood triggered by this exceptionally heavy rainfall event (return period > 1000 years) in the 6.5 km2 Hupsel Brook catchment, which has been the experimental watershed employed by Wageningen University since the 1960s. This study improved our understanding of the dynamics of such lowland flash floods (Brauer et al., 2011). These observations, however, only show how our experimental catchment behaved and the results cannot be extrapolated directly to different floods in other (neighboring) lowland catchments. Therefore, it is necessary to use the information collected in one well-monitored catchment in combination with data from other, less well monitored catchments to find common signatures which could describe the runoff response during a lowland flood as a function of catchment characteristics. Because of the large spatial extent of the rainfall event in August 2010, many brooks and rivers in the Netherlands and Germany flooded. With data from several catchments we investigated the influence of rainfall and catchment characteristics (such as slope, size and land use) on the reaction of discharge to rainfall. We also investigated the runoff response in these catchments during previous floods by analyzing the relation between storage and discharge and the recession curve. In addition to the flood in August 2010, two other floods occurred in The Netherlands in recently. The three floods occurred in different parts of the country, after different types of rainfall events and with different initial conditions. We selected several catchments during each flood to compare their response and find out if these cases are fundamentally different or that they were produced by the same underlying processes and can be treated in a similar manner. Brauer, C. C., Teuling, A.J., Overeem, A., van der Velde, Y., Hazenberg, P., Warmerdam, P. M. M. and Uijlenhoet, R.: Anatomy of extraordinary rainfall and flash flood in a Dutch lowland catchment, Hydrol. Earth Syst. Sci., 15, 1991-2005, 2011.

Brauer, C.; Teuling, R.; Torfs, P.; Hobbelt, L.; Jansen, F.; Melsen, L.; Uijlenhoet, R.

2012-12-01

411

Gait Signal Analysis with Similarity Measure  

PubMed Central

Human gait decision was carried out with the help of similarity measure design. Gait signal was selected through hardware implementation including all in one sensor, control unit, and notebook with connector. Each gait signal was considered as high dimensional data. Therefore, high dimensional data analysis was considered via heuristic technique such as the similarity measure. Each human pattern such as walking, sitting, standing, and stepping up was obtained through experiment. By the results of the analysis, we also identified the overlapped and nonoverlapped data relation, and similarity measure analysis was also illustrated, and comparison with conventional similarity measure was also carried out. Hence, nonoverlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considered high dimensional data analysis was designed with consideration of neighborhood information. Proposed similarity measure was applied to identify the behavior patterns of different persons, and different behaviours of the same person. Obtained analysis can be extended to organize health monitoring system for specially elderly persons. PMID:25110724

Shin, Seungsoo

2014-01-01

412

Generalized similarity in finite range solar wind magnetohydrodynamic turbulence.  

PubMed

Extended or generalized similarity is a ubiquitous but not well understood feature of turbulence that is realized over a finite range of scales. The ULYSSES spacecraft solar polar passes at solar minimum provide in situ observations of evolving anisotropic magnetohydrodynamic turbulence in the solar wind under ideal conditions of fast quiet flow. We find a single generalized scaling function characterizes this finite range turbulence and is insensitive to plasma conditions. The recent unusually inactive solar minimum--with turbulent fluctuations down by a factor of approximately 2 in power--provides a test of this invariance. PMID:20366193

Chapman, S C; Nicol, R M

2009-12-11

413

Generalized Similarity in Finite Range Solar Wind Magnetohydrodynamic Turbulence  

SciTech Connect

Extended or generalized similarity is a ubiquitous but not well understood feature of turbulence that is realized over a finite range of scales. The ULYSSES spacecraft solar polar passes at solar minimum provide in situ observations of evolving anisotropic magnetohydrodynamic turbulence in the solar wind under ideal conditions of fast quiet flow. We find a single generalized scaling function characterizes this finite range turbulence and is insensitive to plasma conditions. The recent unusually inactive solar minimum - with turbulent fluctuations down by a factor of approx2 in power - provides a test of this invariance.

Chapman, S. C.; Nicol, R. M. [Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom)

2009-12-11

414

Wind Turbine Drivetrain Condition Monitoring - An Overview  

SciTech Connect

This paper provides an overview of wind turbine drivetrain condition monitoring based on presentations from a condition monitoring workshop organized by the National Renewable Energy Laboratory in 2009 and on additional references.

Sheng, S; Veers, P.

2011-10-01

415

Adaptive Similarity Measures for Material Identification in Hyperspectral Imagery  

NASA Astrophysics Data System (ADS)

Remotely-sensed hyperspectral imagery has become one the most advanced tools for analyzing the processes that shape the Earth and other planets. Effective, rapid analysis of high-volume, high-dimensional hyperspectral image data sets demands efficient, automated techniques to identify signatures of known materials in such imagery. In this thesis, we develop a framework for automatic material identification in hyperspectral imagery using adaptive similarity measures. We frame the material identification problem as a multiclass similarity-based classification problem, where our goal is to predict material labels for unlabeled target spectra based upon their similarities to source spectra with known material labels. As differences in capture conditions affect the spectral representations of materials, we divide the material identification problem into intra-domain (i.e., source and target spectra captured under identical conditions) and inter-domain (i.e., source and target spectra captured under different conditions) settings. The first component of this thesis develops adaptive similarity measures for intra-domain settings that measure the relevance of spectral features to the given classification task using small amounts of labeled data. We propose a technique based on multiclass Linear Discriminant Analysis (LDA) that combines several distinct similarity measures into a single hybrid measure capturing the strengths of each of the individual measures. We also provide a comparative survey of techniques for low-rank Mahalanobis metric learning, and demonstrate that regularized LDA yields competitive results to the state-of-the-art, at substantially lower computational cost. The second component of this thesis shifts the focus to inter-domain settings, and proposes a multiclass domain adaptation framework that reconciles systematic differences between spectra captured under similar, but not identical, conditions. Our framework computes a similarity-based mapping that captures structured, relative relationships between classes shared between source and target domains, allowing us apply a classifier trained using labeled source spectra to classify target spectra. We demonstrate improved domain adaptation accuracy in comparison to recently-proposed multitask learning and manifold alignment techniques in several case studies involving state-of-the-art synthetic and real-world hyperspectral imagery.

Bue, Brian D.

416

Similarity laws of lunar and terrestrial volcanic flows  

NASA Technical Reports Server (NTRS)

A mathematical model of a one dimensional, steady duct flow of a mixture of a gas and small solid particles (rock) was analyzed and applied to the lunar and the terrestrial volcanic flows under geometrically and dynamically similar conditions. Numerical results for the equilibrium two phase flows of lunar and terrestrial volcanoes under similar conditions are presented. The study indicates that: (1) the lunar crater is much larger than the corresponding terrestrial crater; (2) the exit velocity from the lunar volcanic flow may be higher than the lunar escape velocity but the exit velocity of terrestrial volcanic flow is much less than that of the lunar case; and (3) the thermal effects on the lunar volcanic flow are much larger than those of the terrestrial case.

Pai, S. I.; Hsu, Y.; Okeefe, J. A.

1977-01-01

417

Laboratory modelling of manganese biofiltration using biofilms of Leptothrix discophora.  

PubMed

Laboratory biofilters (pilot-scale, 20 l and laboratory-scale, 5l) were constructed in order to model the bioaccumulation of manganese (Mn) under flow conditions similar to those occurring in biofilters at groundwater treatment sites. The biofilters were operated as monocultures of Leptothrix discophora, the predominant organism in mature Mn oxidising biofilms. Biologically mediated Mn bioaccumulation was successfully modelled in both filter systems. The data obtained showed that in the small-scale biofilter, the Mn concentrations that gave the highest rate of Mn bioaccumulation, shortest maturation time, highest optical density (biomass) and growth rate were between 2000 and 3000 microg x l(-1). The non-problematic scale-up of the process from the laboratory-scale to the pilot-scale biofilter model suggests that Mn biofilters may be 'seeded' with laboratory grown cultures of L. discophora. By initially operating the biofilter as a re-circulating batch culture, with an initial Mn concentration of approximately 2500 microg x l(-1), it is hoped to reduce the filter maturation time from months to days. PMID:15026240

Hope, C K; Bott, T R

2004-04-01

418

Structural similarities between biogenic uraninites produced by phylogenetically and metabolically diverse bacteria.  

SciTech Connect

While the product of microbial uranium reduction is often reported to be“UO2”, a comprehensive characterization including stoichiometry and unit cell determination is available for only one Shewanella species. Here, we compare the products of batch uranyl reduction by a collection of dissimilatory metal- and sulfate-reducing bacteria of the genera Shewanella, Geobacter, Anaeromyxobacter, and Desulfovibrio under similar laboratory conditions. Our results demonstrate that U(VI) bioreduction by this assortment of commonly studied, environmentally relevant bacteria leads to the precipitation of uraninite with a composition between UO2.00 and UO2.075, regardless of phylogenetic or metabolic diversity. Coupled analyses, including electron microscopy, X-ray absorption spectroscopy, and powder diffraction, confirm that structurally and chemically analogous uraninite solids are produced. These biogenic uraninites have particle diameters of about 2-3 nm and lattice constants consistent with UO2.0 and exhibit a high degree of intermediate-range order. Results indicate that phylogenetic and metabolic variability within delta- and gamma-proteobacteria has little effect on nascent biouraninite structure or crystal size under the investigated conditions.

Sharp, Jonathan; Schofield, Eleanor J.; Veeramani, Harish; Suvorova, Elena; Kennedy, David W.; Marshall, Matthew J.; Mehta, Apurva; Bargar, John R.; Bernier-Latmani, Rizlan

2009-11-01

419

Chemistry Laboratory Safety Check  

ERIC Educational Resources Information Center

An accident prevention/safety check list for chemistry laboratories is printed. Included are checks of equipment, facilities, storage and handling of chemicals, laboratory procedures, instruction procedures, and items to be excluded from chemical laboratories. (SL)

Patnoe, Richard L.

1976-01-01

420

Asymptotically Self-Similar Propagation of Spherical Ionization Waves  

Microsoft Academic Search

It is shown that a new type of the self-similar spherical ionization waves\\u000amay exist in gases. All spatial scales and the propagation velocity of such\\u000awaves increase exponentially in time. Conditions for existence of these waves\\u000aare established, their structure is described and approximate analytical\\u000arelationships between the principal parameters are obtained. It is notable that\\u000aspherical ionization waves

A. S. Kyuregyan

2008-01-01

421

Asthma and COPD: Differences and Similarities  

MedlinePLUS

... My Membership About the AAAAI Share | Asthma and COPD: Differences and Similarities This article has been reviewed ... or you could have Chronic Obstructive Pulmonary Disease (COPD) , such as emphysema or chronic bronchitis. Because asthma ...

422

Self-similar dynamics of morphogen gradients  

NASA Astrophysics Data System (ADS)

Morphogen gradients are concentration fields of molecules acting as spatial regulators of cell differentiation in developing tissues and play a fundamental role in various aspects of embryonic development. We discovered a family of self-similar solutions in a canonical class of nonlinear reaction-diffusion models describing the formation of morphogen gradients. These solutions are realized in the limit of infinitely high production rate at the tissue boundary and are given by the product of the steady state concentration profile and a function of the diffusion similarity variable. We solved the boundary value problem for the similarity profile numerically and analyzed the implications of the discovered self-similarity on the dynamics of morphogenetic patterning.

Muratov, Cyrill B.; Gordon, Peter V.; Shvartsman, Stanislav Y.

2011-10-01

423

Exploring the Similarities between Potential Smoothing and  

E-print Network

Exploring the Similarities between Potential Smoothing and Simulated Annealing REECE K. HART,1 of Computational Chemistry, Vol. 21, No. 7, 531­552 (2000) c 2000 John Wiley & Sons, Inc. #12;HART, PAPPU

Ponder, Jay

424

HYPOTHESIS TESTING WITH THE SIMILARITY INDEX  

EPA Science Inventory

Mulltilocus DNA fingerprinting methods have been used extensively to address genetic issues in wildlife populations. Hypotheses concerning population subdivision and differing levels of diversity can be addressed through the use of the similarity index (S), a band-sharing coeffic...

425

Interpersonal Congruency, Attitude Similarity, and Interpersonal Attraction  

ERIC Educational Resources Information Center

As no experimental study has examined the effects of congruency on attraction, the present investigation orthogonally varied attitude similarity and interpersonal congruency in order to compare the two independent variables as determinants of interpersonal attraction. (Author/RK)

Touhey, John C.

1975-01-01

426

Conceptual combination: does similarity predict emergence?  

E-print Network

Conceptual combination is used as a paradigm for investigating the influence of similarity on emergence. Subjects were 180 undergraduates recruited from the psychology subject pool. Pairs of parent concepts were selected for study using a...

Wilkenfeld, Merryl Joy

2012-06-07

427

Self-similarity in Laplacian growth  

SciTech Connect

We consider Laplacian Growth of self-similar domains in different geometries. Self-similarity determines the analytic structure of the Schwarz function of the moving boundary. The knowledge of this analytic structure allows us to derive the integral equation for the conformal map. It is shown that solutions to the integral equation obey also a second-order differential equation which is the 1D Schroedinger equation with the sinh{sup -2}-potential. The solutions, which are expressed through the Gauss hypergeometric function, characterize the geometry of self-similar patterns in a wedge. We also find the potential for the Coulomb gas representation of the self-similar Laplacian growth in a wedge and calculate the corresponding free energy.

Mineev-weinstein, Mark [Los Alamos National Laboratory; Zabrodin, Anton [ITEP, MOSCOW, RUSSIA; Abanov, Artem [TEXAS A & M

2008-01-01

428

Background Knowledge, Category Labels, and Similarity Judgment  

E-print Network

proposes that labels are not essentially different from physical features: shared labels increase overall similarity between two items in the same way as shared physical features. The other view suggests that people have a naïve theory that shared labels...

Yu, Na-Yung

2011-10-21

429

Towards integrative gene functional similarity measurement  

PubMed Central

Background In Gene Ontology, the "Molecular Function" (MF) categorization is a widely used knowledge framework for gene function comparison and prediction. Its structure and annotation provide a convenient way to compare gene functional similarities at the molecular level. The existing gene similarity measures, however, solely rely on one or few aspects of MF without utilizing all the rich information available including structure, annotation, common terms, lowest common parents. Results We introduce a rank-based gene semantic similarity measure called InteGO by synergistically integrating the state-of-the-art gene-to-gene similarity measures. By integrating three GO based seed measures, InteGO significantly improves the performance by about two-fold in all the three species studied (yeast, Arabidopsis and human). Conclusions InteGO is a systematic and novel method to study gene functional associations. The software and description are available at http://www.msu.edu/~jinchen/InteGO. PMID:24564710

2014-01-01

430

Searching Similar Modules in Protein Interaction Netwo  

Microsoft Academic Search

Abstract Wedeveloped,a new ,method ,to search ,protein networks functionally similar to a ,given query signal transduction,pathway ,within ,protein ,interaction networks. This method ,consists of two ,parts: 1) a backtracking,search algorithm ,to find ,topologically identical subgraphs ,and ,2) a ,measurement ,of similarity between ,proteins by using ,Gene Ontology [1]. For validation of our method, we implemented a software tool and compared,its

Hiroyuki Oka; Masanori Arita

2005-01-01

431

The Similarity Index and DNA Fingerprinting  

Microsoft Academic Search

DNA-fingerprint similarity is being used increasingly to make inferences about levels of genetic variation within and between natural populations. It is shown that the similarity index-the average fraction of shared restriction fragments-provides upwardly biased estimates of population homozygosity but nearly unbiased estimates of the average identity-in-state for random pairs of individuals. A method is suggested for partitioning the DNA-fingerprint dissimilarity

Michael Lynch

432

Video abstraction based on asymmetric similarity values  

NASA Astrophysics Data System (ADS)

The paper addresses visual similarity measuring and hierarchical groping of the most representative frames for the purpose of video abstraction. Our approach concentrates on measuring similarity of image regions. To produce a visual similarity measure we used as primary information the color histograms in the YUV color space. The difference from previous histogram based approaches is that we divide the input images into rectangles whose sizes depend on the local 'structure' of the image. We assume that similar regions in two different images would have approximately the same rectangle structure. Therefore, it should ge enough to compare the color histogram of the pixels within these rectangles in order to determine the similarity of two regions in two different images. We measure similarity between regions by a similarity score that is asymmetric. Such a measure cannot be used in classical clustering techniques for grouping representative frames. Our approach is therefore based on graph theoretic techniques. First, we construct an oriented weighted graph having as vertices the original set of key-frames. Next, we construct the set of weighted edges, according to the similarity values computed for each ordered pair of key-frames. Finally, we transform this graph into a collection of two-level trees, whose root key-frames form an abstract of the original ones. For graph construction and transformation, we present here two algorithms. The experiments we performed with the proposed technique showed improvements with respect to the way the visual content is represented. This conclusion is based on subjective assessment of the result groupings and the selection of the most representative key-frame.

Iacob, Sorin M.; Lagendijk, Reginald L.; Iacob, M. E.

1999-08-01

433

Tool for defining catchment similarity matrix  

NASA Astrophysics Data System (ADS)

It is important to classify catchments for many reasons, for example, for prediction in ungauged basins, model parameterization and watershed development. There have been many studies on catchment classification, but no silver bullet exists for choosing the most relevant measure of catchment similarity. The aim of this study is to explore a new measure of similarity among catchments, using a data depth function. We used a similarity measure called "Depth-Depth plot" (DD-plot) which measures similarity in the catchment flow dynamics in multiple dimension. The area under the convex hull of DD-plot can be used as similarity matrix to any clustering technique. In this study we used Affinity propagation (AP) clustering algorithm for grouping the similar catchments. Catchment classifications based on flow and physical characteristics were compared. We evaluate whether the similarity based on depth-depth plots provides a better basis for transferring parameter sets of a hydrological model between catchments. We used a case study of 21 catchments located in the Bay of Plenty region in the North Island of New Zealand. The catchments have a wide range of topographic properties, response behaviours and geological features. The TopNet hydrological model was calibrated for all the catchments and the transferability of model parameters among the similar catchments was tested by transferring the parameters from within the cluster group and outside the group. The results of parameter transferred with in group based on Nash-Sutcliffe coefficient are promising. Results also show that clustering based on our proposed depth-depth measure, catchment characteristics, flow, and flow indices are different. The catchment classification of this study can be used to improve regional flood forecasting capabilities.

Singh, Shailesh Kumar; McMillan, Hilary; Bárdossy, András; Fateh, Chebana

2014-05-01

434

Predicting Odor Perceptual Similarity from Odor Structure  

PubMed Central

To understand the brain mechanisms of olfaction we must understand the rules that govern the link between odorant structure and odorant perception. Natural odors are in fact mixtures made of many molecules, and there is currently no method to look at the molecular structure of such odorant-mixtures and predict their smell. In three separate experiments, we asked 139 subjects to rate the pairwise perceptual similarity of 64 odorant-mixtures ranging in size from 4 to 43 mono-molecular components. We then tested alternative models to link odorant-mixture structure to odorant-mixture perceptual similarity. Whereas a model that considered each mono-molecular component of a mixture separately provided a poor prediction of mixture similarity, a model that represented the mixture as a single structural vector provided consistent correlations between predicted and actual perceptual similarity (r?0.49, p<0.001). An optimized version of this model yielded a correlation of r?=?0.85 (p<0.001) between predicted and actual mixture similarity. In other words, we developed an algorithm that can look at the molecular structure of two novel odorant-mixtures, and predict their ensuing perceptual similarity. That this goal was attained using a model that considers the mixtures as a single vector is consistent with a synthetic rather than analytical brain processing mechanism in olfaction. PMID:24068899

Weiss, Tali; Frumin, Idan; Khan, Rehan M.; Sobel, Noam

2013-01-01