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1

Syllable acoustics, temporal patterns, and call composition vary with behavioral context in Mexican free-tailed bats  

PubMed Central

Recent research has shown that some bat species have rich vocal repertoires with diverse syllable acoustics. Few studies, however, have compared vocalizations across different behavioral contexts or examined the temporal emission patterns of vocalizations. In this paper, a comprehensive examination of the vocal repertoire of Mexican free-tailed bats, T. brasiliensis, is presented. Syllable acoustics and temporal emission patterns for 16 types of vocalizations including courtship song revealed three main findings. First, although in some cases syllables are unique to specific calls, other syllables are shared among different calls. Second, entire calls associated with one behavior can be embedded into more complex vocalizations used in entirely different behavioral contexts. Third, when different calls are composed of similar syllables, distinctive temporal emission patterns may facilitate call recognition. These results indicate that syllable acoustics alone do not likely provide enough information for call recognition; rather, the acoustic context and temporal emission patterns of vocalizations may affect meaning.

Bohn, Kirsten M.; Schmidt-French, Barbara; Ma, Sean T.; Pollak, George D.

2008-01-01

2

Optimal design of large composite panels with varying loads  

Microsoft Academic Search

This paper presents an optimization formulation for the design of large composite panels when loads vary over the panel. A methodology termed “blending” is introduced and used to ensure that a panel is manufacturable. Two ways of specifying the blending rules in optimal design formulation are set forth and compared. A global optimization algorithm, Improving Hit-and-Run (IHR), is used to

Birna P. Kristinsdottir; Zelda B. Zabinsky; Mark E. Tuttle; Sudipto Neogi

2001-01-01

3

Call Combinations in Monkeys: Compositional or Idiomatic Expressions?  

ERIC Educational Resources Information Center

Syntax is widely considered the feature that most decisively sets human language apart from other natural communication systems. Animal vocalisations are generally considered to be holistic with few examples of utterances meaning something other than the sum of their parts. Previously, we have shown that male putty-nosed monkeys produce call

Arnold, Kate; Zuberbuhler, Klaus

2012-01-01

4

Composite laminates with spatially varying fiber orientations - 'Variable stiffness panel concept'  

NASA Technical Reports Server (NTRS)

A solution has been obtained to the plane elasticity problem for a symmetrically laminated composite panel with spatially varying fiber orientations. Since variation of the fiber angles along the length of a composite laminate results in stiffness properties that change as a function of location, the laminates are called variable stiffness panels. An analysis of the stiffness variation and its effect on the elastic response of the panel is presented here. A numerical solution has been obtained using an iterative collocation technique. Corresponding closed-form solutions are given for three different sets of boundary conditions. Two of the cases considered have exact solutions and thus serve to validate the numerical model.

Guerdal, Zafer; Olmedo, Reynaldo

1992-01-01

5

Female reciprocal calling in the Iberian midwife toad ( Alytes cisternasii) varies with male call rate and dominant frequency: implications for sexual selection  

NASA Astrophysics Data System (ADS)

Male midwife toads ( Alytes cisternasii) responded differently depending on the call frequency and call rate of other males. I tested female Iberian midwife toads with the same set of stimuli used earlier with males. Females responded faster to high call rates, and female vocal activity was greater in response to low-frequency male calls. Thus, in both sexes, the vocal response differs in the same direction according to signal frequency variation, but the magnitude of the response is greater in males than in females. In the light of these results, I discuss the implications for sexual selection of this reciprocal calling.

Bosch, Jaime

2001-10-01

6

Dictyostelium Cells Migrate Similarly on Surfaces of Varying Chemical Composition  

PubMed Central

During cell migration, cell-substrate binding is required for pseudopod anchoring to move the cell forward, yet the interactions with the substrate must be sufficiently weak to allow parts of the cell to de-adhere in a controlled manner during typical protrusion/retraction cycles. Mammalian cells actively control cell-substrate binding and respond to extracellular conditions with localized integrin-containing focal adhesions mediating mechanotransduction. We asked whether mechanotransduction also occurs during non-integrin mediated migration by examining the motion of the social amoeba Dictyostelium discoideum, which is thought to bind non-specifically to surfaces. We discovered that Dictyostelium cells are able to regulate forces generated by the actomyosin cortex to maintain optimal cell-surface contact area and adhesion on surfaces of various chemical composition and that individual cells migrate with similar speed and contact area on the different surfaces. In contrast, during collective migration, as observed in wound healing and metastasis, the balance between surface forces and protrusive forces is altered. We found that Dictyostelium collective migration dynamics are strongly affected when cells are plated on different surfaces. These results suggest that the presence of cell-cell contacts, which appear as Dictyostelium cells enter development, alter the mechanism cells use to migrate on surfaces of varying composition.

Wang, Chenlu; Losert, Wolfgang; Parent, Carole A.

2014-01-01

7

Device for producing a fluid stream of varying composition  

DOEpatents

A device for producing a fluid stream of varying composition comprises a chamber having an inlet at one end and outlet at the other. Between the inlet and outlet there are substantially planar pans or baffles positioned normal to the bulk flow of fluid between the inlet and the outlet. These pans are arranged in pairs. Each pan, except those of the pair most remote from the inlet, is spaced from the walls of the chamber to permit air to flow past it. The pans of each pair are also spaced from each other, in a direction parallel to their planes, leaving an empty space along the mid-plane of the chamber. This produces a circulation and mixing of fluid between the pairs of pans or baffles. A secondary stream of fluid is introduced between two pairs of baffles in the intermediate portion of the chamber, so that the composition of the fluid is different in the portion adjacent to the outlet and the portion adjacent to the inlet. In a specific embodiment, the device is an exposure chamber for experimental animals, and the pans or baffles are catch pans for excrement.

Moss, Owen R. (Kennewick, WA); Clark, Mark L. (Kennewick, WA); Rossignol, E. John (Richland, WA)

1982-01-01

8

Osteoblast response to dimethacrylate composites varying in composition, conversion and roughness using a combinatorial approach  

PubMed Central

Dimethacrylate polymers and composites are seeing increased usage in orthopedics. As these applications require the material to integrate with the surrounding tissues, direct contact cytotoxicity assays should be used to assess the biocompatibility. This study utilized a combinatorial testing platform to evaluate the cell response to dimethacrylate composites with a variety of properties on a single sample. MC3T3-E1 pre-osteoblasts were cultured directly on composites with varying filler content, filler type, degree of conversion (DC), and surface topography. Cell viability, density, and area depended on an interplay of the material properties, with low DC causing a reduction in cell area but having minimal effect on cell viability, high filler content causing an increase in cell density, and filler content/type altering the surface roughness as a function of DC. The combinatorial testing platform successfully quantified the effects of numerous material properties on several aspects of the osteoblast response.

Lin-Gibson, Sheng

2009-01-01

9

Model atmospheres for cool stars. [varying chemical composition  

NASA Technical Reports Server (NTRS)

This report contains an extensive series of model atmospheres for cool stars having a wide range in chemical composition. Model atmospheres (temperature, pressure, density, etc.) are tabulated, along with emergent energy flux distributions, limb darkening, and information on convection for selected models. The models are calculated under the usual assumptions of hydrostatic equilibrium, constancy of total energy flux (including transport both by radiation and convection) and local thermodynamic equilibrium. Some molecular and atomic line opacity is accounted for as a straight mean. While cool star atmospheres are regimes of complicated physical conditions, and these atmospheres are necessarily approximate, they should be useful for a number of kinds of spectral and atmospheric analysis.

Johnson, H. R.

1974-01-01

10

Masseter Myosin Heavy Chain Composition Varies With Mandibular Asymmetry  

PubMed Central

Human jaw dysmorphologies are frequent and often affect young patients, resulting in malocclusion of teeth and inappropriate jaw relationships. Treatment is performed by means of orthodontics with orthognathic surgery as required. Mandibular asymmetry is one of the most frequent dysmorphologies, but in many cases, the specific cause is unknown. In healthy patients who were undergoing orthognathic surgery for correction of malocclusion, we tested the hypothesis that masseter muscle phenotype composition, which determines contractile properties, was different between sides in patients with mandibular asymmetry but not in those without mandibular asymmetry. After cephalometric analysis, 50 patients from whom we obtained samples of both right and left masseter muscles were separated into 2 groups: with or without mandibular lateral deviation. Samples were immunostained with myosin-isoform–specific antibodies to identify 4 skeletal muscle fiber types, and their fiber areas and proportions were measured. Two-tailed Wilcoxon test for paired samples was used to compare the 4 fiber-type compositions by means of percent occupancy and mean fiber area on both sides. Patients with mandibular asymmetry were associated with a significant increase of type II fiber occupancy (P = 0.0035) on the same side as the deviation. This finding that masseter muscle phenotype is significantly linked to mandibular asymmetry is of relevance to physiotherapeutic and surgical managements of jaw discrepancies and merits further investigation in the light of its possible role in the etiology of this condition.

Raoul, Gwenael; Rowlerson, Anthea; Sciote, James; Codaccioni, Emmanuel; Stevens, Laurence; Maurage, Claude-Alain; Duhamel, Alain; Ferri, Joel

2014-01-01

11

CUTTING FORCES AND SURFACE ROUGHNESS IN MACHINING Al\\/SiCp COMPOSITES OF VARYING COMPOSITION  

Microsoft Academic Search

Knowing that the machined surface roughness of Al\\/SiCp composites is linked to its performance, this paper presents an elaborative experimentation using Taguchi methods on four composites to analyze the effects of size (15 ?m and 65 ?m) and volume fraction (20% and 30%) of reinforcements in the composites on machining forces and machined surface roughness. The independent variables in the experiment were:

Uday A. Dabade; Harshad A. Sonawane; Suhas S. Joshi

2010-01-01

12

Object oriented model for composite reliability evaluation including time varying load and wind generation  

Microsoft Academic Search

This paper presents a flexible object-oriented computational model for composite systems reliability evaluation based on Sequential and Non-Sequential Monte Carlo Simulation. The main focus of the model is in the representation of time varying components, such as the wind generation and the load. The modeling flexibility enables the representation of complex network components and the comparison of indices obtained by

Júlio Alberto Silva Dias; C. L. Tancredo Borges

2010-01-01

13

Forced torsional properties of PMR composites with varying nadic ester concentrations and processing histories  

NASA Technical Reports Server (NTRS)

PMR polyimide resin was prepared from 4,4'-methylenedianiline, the dimethyl ester of 3,3',4,4'-benzophenonetetracarboxylic acid and the monomethyl ester of 5-norbornene-2,3-dicarboxylic acid (NE). The NE group serves as a chain terminator and crosslinking site. PMR/Celion 6000 composites were fabricated from resins having varying NE concentrations using two molding processes, and the laminates characterized in forced torsion. Glass transition temperatures (T(g)) of 360-390 C were observed in the crosslinked resins, as compared with the literature value of 284 C reported for the uncrosslinked system. T(g) did not decrease with decreasing NE concentrations over the range from 2.0 to 1.25 moles. Stoichiometry, within the range studied, showed little influence on shear properties; however, a 25% variation in matrix shear modulus with processing was observed. The G(12) values determined in forced torsion were in excellent agreement with those reported from tensile tests of + or - 45 deg laminates. A branching and possible secondary crosslink mechanism is proposed based on dynamic mechanical behavior and infrared spectra of the composites.

Hurwitz, F. I.

1982-01-01

14

Controlled combustion tests and bottom ash analysis using household waste with varying composition.  

PubMed

The influence of the co-combustion of household waste with either sewage sludge, shredder fluff, electronic and electrical waste (WEEE) or PVC on the bottom ash quality and content was investigated under controlled laboratory conditions using a pot furnace. This laboratory approach avoids the interpretation problems related to large variations in input waste composition and combustion conditions that are observed in large scale MSW incinerators. The data for metals content, transfer coefficients and leaching values are presented relative to data for a base household waste composition that did not contain any of the added special wastes. The small WEEE invited direct measurement of precious metals content in the ashes, where measurement accuracy is facilitated by using only mobile phone scrap for small WEEE. The analyses were carried out for different particle size ranges that are of relevance to the recyclability of metals and minerals in the ashes. Positive correlations were found between elements content of the input waste and the bottom ashes, and also between increased levels of Cl, Mo and Cu in the input waste and their leaching in the bottom ashes. These correlations indicate that addition of PVC, small WEEE and shredder fluff in input waste can have a negative influence on the quality of the bottom ashes. Enrichment of Au and Ag occurred in the fractions between 0.15 and 6 mm. The precious metals content represents an economically interesting intrinsic value, even when the observed peak values are properly averaged over a larger volume of ashes. Overall, it has been shown that changes in quality and content of bottom ashes may be traced back to the varied input waste composition. PMID:20675114

Hu, Yanjun; Bakker, Maarten; Brem, Gerrit; Chen, Guanyi

2011-02-01

15

Controlled combustion tests and bottom ash analysis using household waste with varying composition  

SciTech Connect

The influence of the co-combustion of household waste with either sewage sludge, shredder fluff, electronic and electrical waste (WEEE) or PVC on the bottom ash quality and content was investigated under controlled laboratory conditions using a pot furnace. This laboratory approach avoids the interpretation problems related to large variations in input waste composition and combustion conditions that are observed in large scale MSW incinerators. The data for metals content, transfer coefficients and leaching values are presented relative to data for a base household waste composition that did not contain any of the added special wastes. The small WEEE invited direct measurement of precious metals content in the ashes, where measurement accuracy is facilitated by using only mobile phone scrap for small WEEE. The analyses were carried out for different particle size ranges that are of relevance to the recyclability of metals and minerals in the ashes. Positive correlations were found between elements content of the input waste and the bottom ashes, and also between increased levels of Cl, Mo and Cu in the input waste and their leaching in the bottom ashes. These correlations indicate that addition of PVC, small WEEE and shredder fluff in input waste can have a negative influence on the quality of the bottom ashes. Enrichment of Au and Ag occurred in the fractions between 0.15 and 6 mm. The precious metals content represents an economically interesting intrinsic value, even when the observed peak values are properly averaged over a larger volume of ashes. Overall, it has been shown that changes in quality and content of bottom ashes may be traced back to the varied input waste composition.

Hu Yanjun, E-mail: huyanjun@zjut.edu.cn [Zhejiang University of Technology, Chaowang Road 18, 310014 Hangzhou (China); Delft University of Technology, P.O. Box 5048, 2628 CN, Delft (Netherlands); Bakker, Maarten [Delft University of Technology, P.O. Box 5048, 2628 CN, Delft (Netherlands); Brem, Gerrit [University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); Chen Guanyi [Tianjin University, Weijin Road 92, Nankai District, 300072 Tianjin (China)

2011-02-15

16

Composition and properties of the so-called 'diamond-like' amorphous carbon films  

NASA Technical Reports Server (NTRS)

The composition of amorphous 'diamond-like' films made by direct low energy ion beam deposition, R.F. discharge and sputtering was determined by nuclear reaction analysis, IR spectroscopy and microcombustion chemical analysis. The nuclear reaction analysis showed very similar hydrogen depth profiles for all three types of samples. The atomic ratio of hydrogen to carbon was approximately 0.2 at the film surface and rose to approximately 1.0 at a depth of 500 A. The integrated intensity of the C-H stretching band at about 2900 per cm indicates that the amount of chemically bonded hydrogen is less than the total hydrogen content. Combustion analysis confirmed the overall atomic ratio of hydrogen to carbon determined by nuclear reaction analysis. The chemical state of the non-bonded hydrogen was not determined; however, the effective diffusion coefficient computed from the hydrogen depth profile was extremely low. This indicates either that the films are exceedingly impermeable or that the non-bonded hydrogen requires an additional activated step to leave the films, e.g., desorption or chemical reaction.

Angus, J. C.; Stultz, J. E.; Shiller, P. J.; Macdonald, J. R.; Mirtich, M. J.

1984-01-01

17

Identification and characterization of transcript polymorphisms in soybean lines varying in oil composition and content  

PubMed Central

Background Variation in seed oil composition and content among soybean varieties is largely attributed to differences in transcript sequences and/or transcript accumulation of oil production related genes in seeds. Discovery and analysis of sequence and expression variations in these genes will accelerate soybean oil quality improvement. Results In an effort to identify these variations, we sequenced the transcriptomes of soybean seeds from nine lines varying in oil composition and/or total oil content. Our results showed that 69,338 distinct transcripts from 32,885 annotated genes were expressed in seeds. A total of 8,037 transcript expression polymorphisms and 50,485 transcript sequence polymorphisms (48,792 SNPs and 1,693 small Indels) were identified among the lines. Effects of the transcript polymorphisms on their encoded protein sequences and functions were predicted. The studies also provided independent evidence that the lack of FAD2-1A gene activity and a non-synonymous SNP in the coding sequence of FAB2C caused elevated oleic acid and stearic acid levels in soybean lines M23 and FAM94-41, respectively. Conclusions As a proof-of-concept, we developed an integrated RNA-seq and bioinformatics approach to identify and functionally annotate transcript polymorphisms, and demonstrated its high effectiveness for discovery of genetic and transcript variations that result in altered oil quality traits. The collection of transcript polymorphisms coupled with their predicted functional effects will be a valuable asset for further discovery of genes, gene variants, and functional markers to improve soybean oil quality.

2014-01-01

18

Neutron Radiography and Fission Mapping Measurements of Nuclear Materials with Varying Composition and Shielding  

SciTech Connect

Neutron radiography and fission mapping measurements were performed on four measurement objects with varying composition and shielding arrangements at the Idaho National Laboratory's Zero Power Physics Reactor (ZPPR) facility. The measurement objects were assembled with ZPPR reactor plate materials comprising plutonium, natural uranium, or highly enriched uranium and were presented as unknowns for characterization. As a part of the characterization, neutron radiography was performed using a deuterium-tritium (D-T) neutron generator as a source of time and directionally tagged 14 MeV neutrons. The neutrons were detected by plastic scintillators placed on the opposite side of the object, using the time-correlation-based data acquisition of the Nuclear Materials Identification System developed at Oak Ridge National Laboratory. Each object was measured at several rotations with respect to the neutron source to obtain a tomographic reconstruction of the object and a limited identification of materials via measurement of the neutron attenuation. Large area liquid scintillators with pulse shape discrimination were used to detect the induced fission neutrons. A fission site map reconstruction was produced by time correlating the induced fission neutrons with each tagged neutron from the D-T neutron generator. This paper describes the experimental configuration, the ZPPR measurement objects used, and the neutron imaging and fission mapping results.

Mullens, James Allen [ORNL; McConchie, Seth M [ORNL; Hausladen, Paul [ORNL; Mihalczo, John T [ORNL; Grogan, Brandon R [ORNL; Sword, Eric D [ORNL

2011-01-01

19

Chemical composition and enzymatic digestibility of sugarcane clones selected for varied lignin content  

PubMed Central

Background The recalcitrance of lignocellulosic materials is a major limitation for their conversion into fermentable sugars. Lignin depletion in new cultivars or transgenic plants has been identified as a way to diminish this recalcitrance. In this study, we assessed the success of a sugarcane breeding program in selecting sugarcane plants with low lignin content, and report the chemical composition and agronomic characteristics of eleven experimental hybrids and two reference samples. The enzymatic digestion of untreated and chemically delignified samples was evaluated to advance the performance of the sugarcane residue (bagasse) in cellulosic-ethanol production processes. Results The ranges for the percentages of glucan, hemicellulose, lignin, and extractive (based on oven-dry biomass) of the experimental hybrids and reference samples were 38% to 43%, 25% to 32%, 17% to 24%, and 1.6% to 7.5%, respectively. The samples with the smallest amounts of lignin did not produce the largest amounts of total polysaccharides. Instead, a variable increase in the mass of a number of components, including extractives, seemed to compensate for the reduction in lignin content. Hydroxycinnamic acids accounted for a significant part of the aromatic compounds in the samples, with p-coumaric acid predominating, whereas ferulic acid was present only in low amounts. Hydroxycinnamic acids with ester linkage to the hemicelluloses varied from 2.3% to 3.6%. The percentage of total hydroxycinnamic acids (including the fraction linked to lignin through ether linkages) varied from 5.0% to 9.2%, and correlated to some extent with the lignin content. These clones released up to 31% of glucose after 72 hours of digestion with commercial cellulases, whereas chemically delignified samples led to cellulose conversion values of more than 80%. However, plants with lower lignin content required less delignification to reach higher efficiencies of cellulose conversion during the enzymatic treatment. Conclusion Some of the experimental sugarcane hybrids did have the combined characteristics of high biomass and high sucrose production with low lignin content. Conversion of glucan to glucose by commercial cellulases was increased in the samples with low lignin content. Chemical delignification further increased the cellulose conversion to values of more than 80%. Thus, plants with lower lignin content required less delignification to reach higher efficiencies of cellulose conversion during the enzymatic treatment.

2011-01-01

20

Three-dimensional Finite Element Analysis of Stress Distribution in Composite Resin Cores with Fiber Posts of Varying Diameters  

Microsoft Academic Search

Using three-dimensional finite element analysis (3D-FEA), stress distributions in the remaining radicular tooth structure were investigated under the condition of varying diameters of fiber post for fiber post-reinforced composite resin cores (fiber post and core) in maxillary central incisors. Four 3D-FEA models were constructed: (1) fiber post (?1.2, ?1.4, and ?1.6 mm) and composite resin core; and (2) gold-cast post

Kazuhiko OKAMOTO; Teruo INO; Naoki IWASE; Eitaroh SHIMIZU; Megumi SUZUKI; Goh SATOH; Shuji OHKAWA; Masanori FUJISAWA

2008-01-01

21

Composites for bone repair: phosphate glass fibre reinforced PLA with varying fibre architecture.  

PubMed

Internal fixation for bone fractures with rigid metallic plates, screws and pins is a proven operative technique. However, refracture's have been observed after rigid internal fixation with metal plates and plate fixation has been known to cause localised osteopenia under and near the plate. In the present study, resorbable composites comprising a PLA matrix reinforced with iron doped phosphate glass fibres were investigated. Non-woven random mat laminates of approximately 30% and 45% fibre volume fraction (V(f)) were produced, along with unidirectional and 0°-90° samples of approximately 20% V(f). The non-woven composite laminates achieved maximum values of 10 GPa modulus and 120 MPa strength. The 0-90º samples showed unexpectedly low strengths close to matrix value (~50 MPa) although with a modulus of 7 GPa. The UD specimens exhibited values of 130 MPa and 11.5 GPa for strength and modulus respectively. All the modulus values observed were close to that expected from the rule of mixtures. Samples immersed in deionised water at 37°C revealed rapid mechanical property loss, more so for the UD and 0-90º samples. It was suggested that continuous fibres wicked the degradation media into the composite plates which sped up the deterioration of the fibre-matrix interface. The effect was less pronounced in the non-woven random mat laminates due to the discontinuous arrangement of fibres within the composite, making it less prone to wicking. Random mat composites revealed a higher mass loss than the UD and 0°-90° specimens, it was suggested this was due to the higher fibre volume fractions of these composites and SEM studies revealed voidage around the fibres by day 3. Studies of pH of the degradation media showed similar profiles for all the composites investigated. An initial decrease in pH was attributed to the release of phosphate ions into solution followed by a gradual return back to neutral. PMID:21671001

Ahmed, I; Jones, I A; Parsons, A J; Bernard, J; Farmer, J; Scotchford, C A; Walker, G S; Rudd, C D

2011-08-01

22

An Experimental Study on the Fatigue of Cracked Aluminum Plate with Composite Patches Under Varied Temperatures  

Microsoft Academic Search

In this article, fatigue of cracked 2024-T3 aluminum plate repaired with composite patches has been experimentally investigated. In the study, different aluminum thicknesses, numbers of patch layers, and temperatures have been taken into account. The problem has been considered under plain stress and Mode I conditions. First, mechanical properties of the samples used in the experiments have been determined. Then,

Emin Ergun; Muzaffer Topcu; Suleyman Tasgetiren

2011-01-01

23

Attenuation of in situ UV radiation in Mackenzie Delta lakes with varying dissolved organic matter compositions  

NASA Astrophysics Data System (ADS)

In 2004, ultraviolet-B (UVB) and ultraviolet-A (UVA) attenuation were measured in Mackenzie Delta lakes spanning gradients in water renewal rate, dissolved organic carbon (DOC) concentration, and dissolved organic matter (DOM) composition. DOM compositions (ratio of chromophoric DOM (CDOM) to non-chromophoric DOM) in Delta lakes are complex, evolving seasonally via flooding, dilution, macrophyte production, photobleaching, and bacterial metabolism. Attenuation was more strongly related to CDOM absorption coefficients (a330; UVB r2 = 0.69, p < 0.0001; UVA r2 = 0.58, p < 0.0001) than to DOC concentrations due to variable DOM compositions. Attenuation in one set of lakes was well related (linear models) to a330 and total suspended solids (UVB R2 = 0.80, p < 0.0001; UVA R2 = 0.81, p < 0.0001). When these models were applied to other Delta lakes, however, attenuation of UVB was overestimated in 17 of 19 cases and attenuation of UVA was overestimated in all 18 cases. This bias indicates that models are not transferrable among Delta lakes, and likely cannot be applied in other circumpolar delta lakes with similarly complex DOM compositions. Although attenuation is high in Delta lakes (KdUVB 17.1-33.4 m-1; KdUVA 7.7-19.2 m-1), plankton and photoreactive solutes may be exposed to high levels of ultraviolet radiation (UVR) because Delta lakes are shallow, UVB and UVA penetrate the top 19% and 31% of water columns, respectively, and day lengths are extended during open water. Thus, climate change effects on DOM compositions may significantly alter in situ UVR environments in circumpolar delta lakes.

Gareis, Jolie A. L.; Lesack, Lance F. W.; Bothwell, Max L.

2010-09-01

24

FRIT DEVELOPMENT FOR HIGH LEVEL WASTE SLUDGE BATCH 5: COMPOSITIONAL TRENDS FOR VARYING ALUMINUM CONCENTRATIONS  

SciTech Connect

The objective of this study was to experimentally measure the properties and performance of a series of glasses with compositions that could represent Sludge Batch 5 (SB5) as processed at the Defense Waste Processing Facility (DWPF). The data was used to provide recommendations to the Liquid Waste Organization (LWO) regarding blending and washing strategies in preparing SB5 based on acceptability of the glass compositions. These data were also used to guide frit optimization efforts as the SB5 composition was finalized. Glass compositions for this study were developed by combining a series of SB5 composition projections with a group of frits. Three composition projections for SB5 were developed using a model-based approach at Savannah River National Laboratory (SRNL). These compositions, referred to as SB5 Cases B, C and D, projected removal of 25, 50 and 75% (respectively) of the aluminum in Tank 51 through the low temperature aluminum dissolution process. The frits for this study (Frits 530 through 537) were selected based on their predicted operating windows (i.e., ranges of waste loadings over which the predicted properties of the glasses were acceptable) and their potential (based on historical trends) to provide acceptable melt rates for SB5. Six additional glasses were designed to evaluate alternatives for uranium in DWPF-type glasses used for variability studies and some scoping studies. Since special measures are necessary when working with uranium-containing glasses in the laboratory, it is desirable as a cost and time saving measure to find an alternative for uranium to support frit optimization efforts. Hafnium and neodymium were investigated as potential surrogates for uranium, and other glasses were made by simply excluding the radioactive components and renormalizing the glass composition. The study glasses were fabricated and characterized at SRNL. Chemical composition analyses suggested only minor difficulties in meeting the targeted compositions for some of the oxides for some of the glasses. Although minor differences were observed, they did not have a significant impact on the conclusions made in this study. Several of the study compositions showed retention of more than 0.5 wt% SO{sub 4}{sup 2-} in glass. Trevorite (a spinel) was the only crystalline phase that was positively identified in a few of the study glasses after the canister centerline cooled (CCC) heat treatment. Spinels are not of concern as they have been shown to have little impact on the durability of high level waste glasses. The crystallization behavior of the surrogate glasses was generally the same as that of their U{sub 3}O{sub 8}-containing counterparts. There are two pairs that were exceptions: SB5-04 (amorphous) and SB5-24 (possible trevorite), along with SB5-07 (amorphous) and SB5-25 (trevorite). In these cases, the surrogate glasses (SB5-24 and SB5-25) appear to be more conservative (more prone to crystallization) than their U{sub 3}O{sub 8}-containing counterparts. Chemical durability was quantified using the Product Consistency Test (PCT). The normalized leachate (NL) values for B, Li, Na and Si for all of the study glasses were well below those of the Environmental Assessment (EA) benchmark glass, regardless of heat treatment or compositional view. This indicates that all of the glasses had very acceptable durability performance. The highest NL [B] for the study glasses was 0.914 g/L (the quenched version of glass SB5-13), normalized using the measured, bias-correct composition. There was little practical impact of the CCC heat treatment on the PCT responses of the study glasses. The measured PCT responses were predictable by the current {Delta}G{sub p} models. In general, the PCT responses for the surrogate glasses or the glasses without U{sub 3}O{sub 8} were quite similar to their U{sub 3}O{sub 8}-containing counterparts. The average percent error in NL [B] normalized by the measured, bias-corrected compositions for the surrogate glasses compared with their radioactive counterparts was 8.8%. The largest difference in NL

Fox, K; Tommy Edwards; David Best; Irene Reamer; Phyllis Workman

2008-08-28

25

Practical Analysis of materials with depth varying compositions using FT-IR photoacoustic spectroscopy (PAS)  

SciTech Connect

FT-IR photoacoustic spectroscopy (PAS) is discussed as a nondestructive method to probe the molecular composition of materials versus depth on the basis of the analysis of layers of experimentally controllable thickness, which are measured from the sample surface to depths of some tens of micrometers, depending on optical and thermal properties. Computational methods are described to process photoacoustic amplitude and phase spectra for both semi-quantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.

J.F. McClelland; R.W. Jones; Siquan Luo

2004-09-30

26

Composites for bone repair: phosphate glass fibre reinforced PLA with varying fibre architecture  

Microsoft Academic Search

Internal fixation for bone fractures with rigid metallic plates, screws and pins is a proven operative technique. However,\\u000a refracture’s have been observed after rigid internal fixation with metal plates and plate fixation has been known to cause\\u000a localised osteopenia under and near the plate. In the present study, resorbable composites comprising a PLA matrix reinforced\\u000a with iron doped phosphate glass

I. AhmedI; I. A. Jones; A. J. Parsons; J. Bernard; J. Farmer; C. A. Scotchford; G. S. Walker; C. D. Rudd

2011-01-01

27

Geochemical controls on microbial community composition from varied hot spring environments  

NASA Astrophysics Data System (ADS)

The microbial diversity of Yellowstone thermal features has been studied for decades; however, a majority of this research has been restricted to a handful of springs, or been focused on a single organism. Therefore, a synthesis of the factors determining the distribution and diversity of Yellowstone thermophiles parkwide has not been possible. The diversity of bacterial and archaeal 16S rRNA genes and the associated geochemistry of 104 Yellowstone thermal springs were surveyed to determine the relationship between geochemistry and microbial community composition. Bacterial or archaeal 16S rRNA genes were detected in 86 of our springs (temperature and pH ranged 35-95°C and 1.7-9.2, respectively). By combining phylogenetic analyses of the microbial communities with geochemical data, controls on the community composition were determined. The potential energy available to the microbial communities for reactions that are putative metabolic pathways are modeled. This modeling is based on thermodynamic disequilibrium calculations for coupled redox reactions. This information is used to infer energetically favorable reactions giving insight on what metabolisms are likely important in a spring. The communities sampled grouped into five general types based on organisms and likely terminal electron accepting processes. By combining molecular analysis of the microbial communities with geochemical measurements and energetic calculations, a more comprehensive view of life in thermal environments is presented.

Mitchell, K. R.; Hall, J. R.; Windman, T.; Shock, E. L.; Rodman, A. W.; Nordstrom, D.; Shanks, W.; Morgan, L. A.; Reysenbach, A.; Takacs-Vesbach, C. D.

2008-12-01

28

Thermal property characterization of single crystal diamond with varying isotopic composition  

SciTech Connect

The mirage-effect/thermal wave technique as a modern technique for thermal property characterization is described. The thermal diffusivity of a material is determined by measuring the time and space varying temperature distribution (thermal wave) in the material generated by an intensity modulated heating laser beam. These thermal waves are detected through the deflection of a probe laser beam due to modulation of gradient of the index of refraction (mirage effect) either in the air above the specimens (the in-air technique) or in the specimen itself (the in-solid technique). Three-dimensional theories, for both in-air and in-solid mirage techniques, are represented. In order to extract the material parameters by comparing the theory with experimental data, an extensive data analysis procedure based on multiparameter-least-squares has been developed. The experimental and data analysis details are discussed. Topics concerns with the quality and reliability of the measurements are addressed. This technique has been successfully applied to the thermal property characterization of single crystal diamond with varying isotope contents. The results showed a 50% enhancement in the thermal conductivity by removal of C[sup 13] content from 1.1% to 0.1% in diamond at room temperature. The technique has also been adapted to function in cryogenic temperatures. The temperature dependence of thermal conductivity in the temperature range 80-378K for natural IIA specimen and 187-375K for isotopically enriched specimen are obtained, the former results agree with previous works and the latter results demonstrate the isotope effect on the thermal conductivity of single crystal diamond consistently in a large temperature range. The physical source of this enhancement in diffusivity due to the isotope effect in diamond is discussed. The discussion is based on the full Callaway's theory with emphasizing the role of N-processes in the phonon scattering mechanism.

Wei, L.

1993-01-01

29

Modeled and Measured Dynamics of a Composite Beam with Periodically Varying Foam Core  

NASA Technical Reports Server (NTRS)

The dynamics of a sandwich beam with carbon fiber composite facesheets and foam core with periodic variations in material properties are studied. The purpose of the study is to compare finite element predictions with experimental measurements on fabricated beam specimens. For the study, three beams were fabricated: one with a compliant foam core, a second with a stiffer core, and a third with the two cores alternating down the length of the beam to create a periodic variation in properties. This periodic variation produces a bandgap in the frequency domain where vibrational energy does not readily propagate down the length of the beam. Mode shapes and natural frequencies are compared, as well as frequency responses from point force input to velocity response at the opposite end of the beam.

Cabell, Randolph H.; Cano, Roberto J.; Schiller, Noah H.; Roberts Gary D.

2012-01-01

30

[Pancreatic exocrine secretion to the introduction into the blood of amino acid mixtures of varying composition].  

PubMed

Tests conducted on dogs with a fistula of the pancreatic duct evidenced that various amino acids mixtures containing all the essential amino acids and differing mainly in the replaceable nitrogen dissimilarly act on the external secretion of the pancreas after their introduction into the blood. The most intensive secretion produces a mixture in which the replaceable nitrogen is represented by glycine alone. The mixture, one of its constituent is one of the dicarboxylic acids (glutamic) very poorly stimulates this function. At the same time, the action of all the studied amino acids mixtures is less pronounced than is the effect of the caseine hydrolysate. The commercial agent aminofusin L-600, containing all the essential amino acids with addition of polyols (xylitol and sorbitol) with no dicarboxylic amino acids in its composition, produces an intensive pancreatic secretion close to that caused by the caseine hydrolysate. PMID:28607

Sysoev, Iu A; Kremer, Iu N; Shlygin, G K

1978-01-01

31

Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages  

PubMed Central

Increasing algal cover on tropical reefs worldwide may be maintained through feedbacks whereby algae outcompete coral by altering microbial activity. We hypothesized that algae and coral release compositionally distinct exudates that differentially alter bacterioplankton growth and community structure. We collected exudates from the dominant hermatypic coral holobiont Porites spp. and three dominant macroalgae (one each Ochrophyta, Rhodophyta and Chlorophyta) from reefs of Mo'orea, French Polynesia. We characterized exudates by measuring dissolved organic carbon (DOC) and fractional dissolved combined neutral sugars (DCNSs) and subsequently tracked bacterioplankton responses to each exudate over 48?h, assessing cellular growth, DOC/DCNS utilization and changes in taxonomic composition (via 16S rRNA amplicon pyrosequencing). Fleshy macroalgal exudates were enriched in the DCNS components fucose (Ochrophyta) and galactose (Rhodophyta); coral and calcareous algal exudates were enriched in total DCNS but in the same component proportions as ambient seawater. Rates of bacterioplankton growth and DOC utilization were significantly higher in algal exudate treatments than in coral exudate and control incubations with each community selectively removing different DCNS components. Coral exudates engendered the smallest shift in overall bacterioplankton community structure, maintained high diversity and enriched taxa from Alphaproteobacteria lineages containing cultured representatives with relatively few virulence factors (VFs) (Hyphomonadaceae and Erythrobacteraceae). In contrast, macroalgal exudates selected for less diverse communities heavily enriched in copiotrophic Gammaproteobacteria lineages containing cultured pathogens with increased VFs (Vibrionaceae and Pseudoalteromonadaceae). Our results demonstrate that algal exudates are enriched in DCNS components, foster rapid growth of bacterioplankton and select for bacterial populations with more potential VFs than coral exudates.

Nelson, Craig E; Goldberg, Stuart J; Wegley Kelly, Linda; Haas, Andreas F; Smith, Jennifer E; Rohwer, Forest; Carlson, Craig A

2013-01-01

32

(1)H Nuclear Magnetic Resonance monitoring of the degradation of margarines of varied compositions when heated to high temperature.  

PubMed

In this study, (1)H Nuclear Magnetic Resonance was used to monitor the evolution of three margarines of varied compositions when submitted to heating at 180°C in an oven with aeration. Heating causes degradation of polyunsaturated acyl groups and this depends not only on their unsaturation degree, but also on the concentration of the different acyl groups. The evolution of monounsaturated groups varies depending on the disappearance rate of the groups with higher unsaturation degree. Heat treatment also causes hydrolysis reactions that lead to a reduction in 1-monoglycerides and an increase in 1,2-diglycerides, especially in the margarines with higher water content, as well as degradation of some vegetable sterols. Different types of aldehydes and epoxides were identified and quantified, above all in the margarine with the highest proportion of polyunsaturated groups, especially linoleic; some of these are toxic, such as 4-hydroxy- and 4,5-epoxy-2-alkenals. PMID:25038657

Ibargoitia, María L; Sopelana, P; Guillén, María D

2014-12-15

33

Oxygen Consumption Constrains Food Intake in Fish Fed Diets Varying in Essential Amino Acid Composition  

PubMed Central

Compromisation of food intake when confronted with diets deficient in essential amino acids is a common response of fish and other animals, but the underlying physiological factors are poorly understood. We hypothesize that oxygen consumption of fish is a possible physiological factor constraining food intake. To verify, we assessed the food intake and oxygen consumption of rainbow trout fed to satiation with diets which differed in essential amino acid (methionine and lysine) compositions: a balanced vs. an imbalanced amino acid diet. Both diets were tested at two water oxygen levels: hypoxia vs. normoxia. Trout consumed 29% less food under hypoxia compared to normoxia (p<0.001). Under both hypoxia and normoxia trout significantly reduced food intake by 11% and 16% respectively when fed the imbalanced compared to the balanced amino acid diet. Oxygen consumption of the trout per unit body mass remained identical for both diet groups not only under hypoxia but also under normoxia (p>0.05). This difference in food intake between diets under normoxia together with the identical oxygen consumption supports the hypothesis that food intake in fish can be constrained by a set-point value of oxygen consumption, as seen here on a six-week time scale.

Saravanan, Subramanian; Geurden, Inge; Figueiredo-Silva, A. Claudia; Nusantoro, Suluh; Kaushik, Sadasivam; Verreth, Johan; Schrama, Johan W.

2013-01-01

34

Characterization of the morphology of fast-tumbling bicelles with varying composition.  

PubMed

Small, fast-tumbling bicelles are frequently used in solution NMR studies of protein-lipid interactions. For this purpose it is critical to have information about the organization of the lipids within the bicelle structure. We have studied the morphology of small, fast-tumbling bicelles containing DMPC and DHPC as a function of temperature, lipid concentration, and the relative ratio (q value) of lipid (DMPC) to detergent (DHPC) amounts. Dynamic light scattering and cryo-transmission electron microscopy techniques were used to measure the size of the bicelles and to monitor the shape and dispersity of the particles in the samples. The stability and size of DMPC-containing bicelle mixtures were found to be highly dependent on temperature and the total lipid concentration for mixtures with q = 1 and q = 1.5. Stable DMPC/DHPC bicelles are only formed at low q values (0.5). Bicelle mixtures with q > 0.5 appear to be multidisperse containing more than one component, one with rH around 2.5 nm and one with rH of 6-8 nm. This is interpreted as a coexistence of small (possibly mixed micelles) bicelles and much larger bicelles. Incubating the sample at 37 °C increases the phase separation. Moreover, low total amphiphile concentrations and low q values lead to the formation of a temperature-independent morphology, interpreted as the formation of small particles in which the DHPC and DMPC are more mixed. On the basis of these results, we propose the existence of a critical bicelle concentration, a parameter that determines the existence of bilayered bicelles, which varies with q value. This polymorphism was not observed at any concentrations for q = 0.5 bicelles, for which a small but detectable temperature dependence was observed at high concentrations. The results demonstrate that q = 0.5 mixtures predominantly form "classical" bicelles, but that caution is needed when using fast-tumbling mixtures with q values higher than 0.5. PMID:24785902

Ye, Weihua; Lind, Jesper; Eriksson, Jonny; Mäler, Lena

2014-05-20

35

Pigment epithelium-Derived Factor (PEDF) Varies with Body Composition and Insulin Resistance in Healthy Young People  

PubMed Central

Context: Pigment epithelium-derived factor (PEDF) was recently implicated as a metabolic regulatory protein because plasma concentration was increased in obese or insulin resistant adults. To our knowledge, circulating PEDF values in children have not been reported. Because PEDF is a predictor of metabolic health in adults, it may have a similar impact on metabolic profiles in children. Objective: The objective of the study was to determine whether PEDF in normal-weight (NW) and overweight/obese (OW) children and young adults varies with age, sex, or body composition or is associated with clinical markers of metabolic disease. Setting: Volunteers were tested at the University of Oklahoma Health Sciences Center. Participants: Ninety-one NW (8–30 yr old) and 105 OW (8–35 yr old) males and females participated in the study. Main Outcome Measures: Body composition, blood pressure, arterial compliance, fasting plasma PEDF, glucose, insulin, (used for homeostasis model assessment of insulin resistance), triglycerides, cholesterol (total, low density lipoprotein, and high density lipoprotein), and C-reactive protein. Results: PEDF was 60% higher in the OW vs. NW participants but did not differ between males and females. PEDF was positively correlated with body mass, body mass index, fat and lean mass, fasting insulin, and homeostasis model assessment of insulin resistance in both the NW and OW groups. Multiple regression models revealed that fat and lean mass were significant predictors of circulating PEDF levels independent of age, sex, and body mass index category. Conclusions: Plasma PEDF is elevated in OW youth and is positively associated with insulin resistance. These findings suggest that PEDF may play a role in the development of cardiometabolic dysfunction in youth.

Sunderland, Kyle L.; Tryggestad, Jeanie B.; Wang, Joshua J.; Teague, April M.; Pratt, Lauren V.; Zhang, Sarah X.; Thompson, David M.

2012-01-01

36

Effect of varying carbohydrate and fat content of milk replacer on body composition of Holstein bull calves.  

PubMed

The objective of this study was to determine the effect of varying concentrations of dietary fat and carbohydrate on changes in body composition of Holstein bull calves fed under isocaloric and isonitrogenous intake conditions. Thirty-two calves were assigned to a randomized block design with three dietary treatments, eight calves per treatment, and one baseline group of eight calves. Animals were reared from birth to 85 kg live BW (SEM = 0.57). All calves began treatments between 2 and 6 d of age. Three different milk replacer treatment diets were designed to deliver 14.8 (low fat, LF), 21.6 (medium fat, MF), or 30.6% of DM (high fat, HF) fat; 55.3, 46.7, or 35.4% of DM lactose; and 23.5, 24.8, or 27.0% of DM CP, respectively. Gross energy values were 4.62, 5.09, and 5.77 Mcal/kg for the LF, MF, and HF milk replacers, respectively. From d 1 to 14, calves were offered 0.24 Mcal intake energy/kg BW(0.75), adjusted weekly based on increases in BW, and 0.28 Mcal intake energy/kg BW(0.75) from d 15 to slaughter. Dry feed was not offered. Dry matter, energy, CP, and fat intakes were 55.2 kg, 257.6 Mcal, 13.0 kg, and 8.2 kg; 52.8 kg, 268.8 Mcal, 13.1 kg, and 11.4 kg; and 46.8 kg, 270.3 Mcal, 12.6 kg, and 14.3 kg for the LF, MF and HF treatments, respectively. Energy and CP intakes did not differ among treatments (P = 0.63 and 0.79, respectively). Fat and DMI were different among treatments (P = 0.001 and 0.02, respectively). Empty BW gains were 0.61, 0.61, and 0.65 kg/d for LF, MF, and HF, respectively, and were not different among treatments (P = 0.27). Empty body CP, water, and ash gain were not different among treatments (P = 0.65, 0.99, and 0.57, respectively). Empty body retained energy and fat gain were 27.2 and 57.7% greater for calves fed the HF than for those fed the LF diet (P = 0.06 and 0.006, respectively). Fat as a percentage of the whole empty body on a water-free basis was lower for calves consuming the LF diet (28.6%) than for those fed the HF diet (34.6%), whereas percentage of CP on an empty body, water-free basis was greater for calves consuming the LF diet (59.2%) than for those fed the HF diet (54.9%) (P = 0.006). The results of this study demonstrated that, under isocaloric and isonitrogenous intake conditions, equivalent dietary energy from fat compared to carbohydrate, above 15% fat, has no beneficial purpose unless additional fat deposition is required in the animal. Further, the data demonstrate significant changes in body composition independent of growth rate. PMID:11583412

Tikofsky, J N; Van Amburgh, M E; Ross, D A

2001-09-01

37

The effect of neutron-irradiation on the shear properties of SiC\\/SiC composites with varied interface  

Microsoft Academic Search

The materials used in this study were unidirectional Hi-NicalonTM SiC fibers reinforced SiC matrix composites. SiC\\/SiC composites were fabricated by chemical vapor infiltration (CVI) method. Fibers were coated with either pyrolytic carbon, multiple SiC layers or `porous' SiC by CVI method prior to matrix deposition. They were irradiated in the High Flux Isotope Reactor at damage level of 0.5 dpa.

T. Hinoki; L. L. Snead; Y. Katoh; A. Kohyama; R. Shinavski

2000-01-01

38

The effect of neutron-irradiation on the shear properties of SiC/SiC composites with varied interface  

NASA Astrophysics Data System (ADS)

The materials used in this study were unidirectional Hi-Nicalon TM SiC fibers reinforced SiC matrix composites. SiC/SiC composites were fabricated by chemical vapor infiltration (CVI) method. Fibers were coated with either pyrolytic carbon, multiple SiC layers or `porous' SiC by CVI method prior to matrix deposition. They were irradiated in the High Flux Isotope Reactor at damage level of 0.5 dpa. Irradiation temperatures were either 300°C or 500°C. Interfacial shear properties and mechanical properties were evaluated. The correlation between interfacial shear properties and mechanical properties was examined. The `porous' SiC interface showed a strong bond when compared with the pyrolytic C and multiple SiC interface in the non-irradiated state. The interfacial shear properties were substantially degraded by irradiation with the `porous' SiC showing the most degradation.

Hinoki, T.; Snead, L. L.; Katoh, Y.; Kohyama, A.; Shinavski, R.

2000-12-01

39

Different Assembly Processes Drive Shifts in Species and Functional Composition in Experimental Grasslands Varying in Sown Diversity and Community History  

PubMed Central

Background The prevalence of different biotic processes (limiting similarity, weaker competitor exclusion) and historical contingency due to priority effects are in the focus of ongoing discussions about community assembly and non-random functional trait distributions. Methodology/Principal Findings We experimentally manipulated assembly history in a grassland biodiversity experiment (Jena Experiment) by applying two factorially crossed split-plot treatments to all communities: (i) duration of weeding (never weeded since sowing or cessation of weeding after 3 or 6 years); (ii) seed addition (control vs. seed addition 4 years after sowing). Spontaneous colonization of new species in the control treatment without seed addition increased realized species richness and functional richness (FRic), indicating continuously denser packing of niches. Seed addition resulted in forced colonization and increased realized species richness, FRic, functional evenness (FEve) and functional divergence (FDiv), i.e. higher abundances of species with extreme trait values. Furthermore, the colonization of new species led to a decline in FEve through time, suggesting that weaker competitors were reduced in abundance or excluded. Communities with higher initial species richness or with longer time since cessation of weeding were more restricted in the entry of new species and showed smaller increases in FRic after seed addition than other communities. The two assembly-history treatments caused a divergence of species compositions within communities originally established with the same species. Communities originally established with different species converged in species richness and functional trait composition over time, but remained more distinct in species composition. Conclusions/Significance Contrasting biotic processes (limiting similarity, weaker competitor exclusion) increase functional convergence between communities initially established with different species. Historical contingency with regard to realized species compositions could not be eradicated by cessation of weeding or forced colonization and was still detectable 5 years after application of these treatments, providing evidence for the role of priority effects in community assembly.

Roscher, Christiane; Schumacher, Jens; Gerighausen, Uta; Schmid, Bernhard

2014-01-01

40

THE INFLUENCE OF VARIED NITROGEN FERTILIZATION ON YIELD AND CHEMICAL COMPOSITION OF SWISS CHARD (Beta vulgaris L. var. cicla L.)  

Microsoft Academic Search

The examinations were aimed at determining the dependence between form and rate of applied nitrogen fertilizer vs. yield and chemical composition of leaves of Swiss chard cultivated in greenhouse in spring. Nitrogen was applied in a form of urea, potas- sium nitrate, and ammonium nitrate at three amounts: 0.2; 0.4; 0.6 g N·dm-3 of substrate. Following items were assessed: yield,

Katarzyna Dzida; Karolina Pitura

41

Archaeosomes varying in lipid composition differ in receptor-mediated endocytosis and differentially adjuvant immune responses to entrapped antigen  

PubMed Central

Archaeosomes prepared from total polar lipids extracted from six archaeal species with divergent lipid compositions had the capacity to deliver antigen for presentation via both MHC class I and class II pathways. Lipid extracts from Halobacterium halobium and from Halococcus morrhuae strains 14039 and 16008 contained archaetidylglycerol methylphosphate and sulfated glycolipids rich in mannose residues, and lacked archaetidylserine, whereas the opposite was found in Methanobrevibacter smithii, Methanosarcina mazei and Methanococcus jannaschii. Annexin V labeling revealed a surface orientation of phosphoserine head groups in M. smithii, M. mazei and M. jannaschii archaeosomes. Uptake of rhodamine-labeled M. smithii or M. jannaschii archaeosomes by murine peritoneal macrophages was inhibited by unlabeled liposomes containing phosphatidylserine, by the sulfhydryl inhibitor N-ethylmaleimide, and by ATP depletion using azide plus fluoride, but not by H. halobium archaeosomes. In contrast, N-ethylmaleimide failed to inhibit uptake of the four other rhodamine-labeled archaeosome types, and azide plus fluoride did not inhibit uptake of H. halobium or H. morrhuae archaeosomes. These results suggest endocytosis ofarchaeosomes rich in surface-exposed phosphoserine head groups via a phosphatidylserine receptor, and energy-independent surface adsorption of certain other archaeosome composition classes. Lipid composition affected not only the endocytic mechanism, but also served to differentially modulate the activation of dendritic cells. The induction of IL-12 secretion from dendritic cells exposed to H. morrhuae 14039 archaeosomes was striking compared with cells exposed to archaeosomes from 16008. Thus, archaeosome types uniquely modulate antigen delivery and dendritic cell activation.

Sprott, G. Dennis; Sad, Subash; Fleming, L. Perry; DiCaire, Chantal J.; Patel, Girishchandra B.; Krishnan, Lakshmi

2003-01-01

42

Nonlinear and Threshold Responses of Grassland Productivity and Species Composition to Increased CO2 Vary with Soil Type  

NASA Astrophysics Data System (ADS)

Climate change is likely to cause nonlinear responses in ecosystem function and threshold changes in species composition. Here we report aboveground net primary productivity (ANPP) responses to a continuous CO2 concentration gradient (250 to 500 ?L L-1,) in experimental grassland communities on three soils differing in water holding capacity and other properties. Communities consisting of four C4 grasses, two C3 forbs, and one legume were established on a lowland clay (vertisol, n=32), an upland clay (mollisol, n=32), and an alluvial sand (alfisol, n=16). The communities were positioned in a stratified random design in the CO2 gradient for five growing seasons, and were irrigated to mimic the average growing season rainfall regime for the study site in Central Texas. ANPP increased with CO2 almost two-fold more on the upland clay and alluvial sand than on the lowland clay (p < 0.0001), because of strong linear responses to CO2 on these soils (R2 = 0.50 to 0.59, p < 0.002) compared to a saturating response to CO2 on the lowland clay (R2 = 0.48, p= 0.01). On the two more responsive soils, the mesic tallgrass Sorghastrum nutans replaced the more drought adapted mid-grass Bouteloua curtipendula at elevated CO2, while B. curtipendula largely replaced S. nutans at low CO2, especially on the upland clay. Evidence for a similar composition change was not found on the lowland clay. Thus, two soils displayed a threshold change in community composition that accounted for up to 57% of variation in ANPP for those soils. Variation in ANPP and species composition with CO2 were accompanied by linear increases in soil water content (SWC, 0 - 20 cm, volumetric), most strongly on the alluvial sand (R2 = 0.39, p < 0.009) and by weak decreases with CO2 in soil N. Structural equation models explained 34 to 52% of the variation in ANPP, and indicated that CO2 effects on ANPP on the upland clay were primarily explained by CO2 effects on species composition, and on the alluvial sand by CO2 effects on SWC. Responses to elevated CO2 in SWC, ANPP, and species composition were explained by reduced stomatal conductance and increased photosynthetic water use efficiency (WUE) in both grasses. In addition, S. nutans gained more in WUE at elevated CO2 than B. curtipendula, while B. curtipendula at elevated CO2 had lower light saturated photosynthetic capacity, quantum use efficiency, and dark respiration than S. nutans. Thus, at elevated CO2, shading by the taller S. nutans likely lowered B. curtipendula carbon assimilation and growth. We conclude that elevated CO2 strongly increased ANPP on upland clay and alluvial sand soils where there were also gains in soil moisture and threshold changes in species composition driven by physiological differences in the two dominant grass species. As a result, CO2 effects on ANPP will likely differ with soil type across the landscape.

Fay, P. A.; Jin, V.; Jackson, R. B.; Gill, R. A.; Way, D.; Polley, W.

2011-12-01

43

Rhizosphere bacterial communities associated with long-lived perennial prairie plants vary in diversity, composition, and structure.  

PubMed

The goal of this research was to investigate the variation in rhizosphere microbial community composition, diversity, and structure among individual Andropogon gerardii Vitman (big bluestem) and Lespedeza capitata Michx. (bush clover). Bacterial communities from the rhizosphere of 10 plants of each species (n = 20 plants total) were explored using a culture-independent pipeline. Microbial communities associated with both host plants had high bacterial diversity within individual plant rhizosphere and taxa unique to individual rhizospheres. Bacterial communities associated with the rhizosphere of A. gerardii were consistently more diverse than those associated with L. capitata, and there were significant differences between plant species in rhizosphere bacterial community composition. Differences included microbial taxa with no known functional relationship with their preferred host species, including sulfide-methylating obligate anaerobes (Holophaga), complete denitrifiers (Rhodoplanes), sludge inhabitants (Ktedonobacter), and nitrate oxidizers (Nitrospira). These results suggest the potential for plant species to have significant impacts on a broad array of ecosystem functions (e.g., cycling of carbon, nitrogen sulfurs, metals, and trace elements) via their selective impacts on soil microbes. However, sequence-based community analysis and the corresponding lack of intact microbial cultures limits understanding of the potential influences of enriched microbial taxa on plant hosts and their roles in ecosystem functioning. PMID:23826959

Rosenzweig, N; Bradeen, J M; Tu, Z J; McKay, S J; Kinkel, L L

2013-07-01

44

Spectroscopic and thermodynamic study of charge transfer complex formation between cloxacillin sodium and riboflavin in aqueous ethanol media of varying composition  

NASA Astrophysics Data System (ADS)

Cloxacillin sodium has been shown to form a charge transfer complex of 2:1 stoichiometry with riboflavin (Vitamin B 2) in aqueous ethanol medium. The enthalpy and entropy of formation of this complex have been determined by estimating the formation constant spectrophotometrically at five different temperatures in pure water medium. Pronounced effect of dielectric constant of the medium on the magnitude of K has been observed by determining K in aqueous ethanol mixtures of varying composition. This has been rationalized in terms of ionic dissociation of the cloxacillin sodium (D -Na +), hydrolysis of the anion D - and complexation of the free acid, DH with riboflavin.

Roy, Dalim Kumar; Saha, Avijit; Mukherjee, Asok K.

2006-03-01

45

Differential uptake of liposomes varying in size and lipid composition by parenchymal and Kupffer cells of mouse liver  

SciTech Connect

Using liposomes differing in size and lipid composition, we have studied the uptake characteristics of the liver parenchymal and Kupffer cells. Desferal labeled with iron-59 was chosen as a radiomarker for the liposomal content, because Desferal in its free form does not cross cellular membranes.At various time intervals after an intravenous injection of liposomes into mice, the liver was perfused with collagenase, and the cells were separated in a Percoll gradient. It was found that large multilamellar liposomes (diameter of about 0.5 ..mu..m) were mainly taken up by the Kupffer cells. For these large liposomes, the rate of uptake by Kupffer cells was rapid, with maximum uptake at around 2 hours after liposme injection. Unexpectedly, small unilamellar liposomes (diameter of about 0.08 ..mu..m) were less effectively taken up by Kupffer cells, and the rate of uptake was slow, with a maximum uptake at about 10 hours after liposome injection. In contrast, parenchymal cells were more effective in taking up small liposmes and the uptake of large liposomes was negligible. In addition, liposomes made with a galactolipid as part of the lipid constituents appeared to have higher affinity to parenchymal cells than liposomes made without the galactolipid. These findings should be of importance in designing suitable liposomes for drug targeting.

Rahman, Y.E.; Cerny, E.A.; Patel, K.R.; Lau, E.H.; Wright, B.J.

1982-11-08

46

Differential uptake of liposomes varying in size and lipid composition by parenchymal and Kupffer cells of mouse liver  

SciTech Connect

Using liposomes differing in size and lipid composition, we have studied the uptake characteristics of the liver parenchymal and Kupffer cells. Desferal labeled with iron-59 was chosen as a radiomarker for the liposomal content, because Desferal in its free form does not cross cellular membranes. At various time intervals after an intravenous injection of liposomes into mice, the liver was perfused with collagenase, and the cells were separated in a Percoll gradient. It was found that large multilamellar liposomes (diameter of about 0.5 ..mu..m) were mainly taken up by the Kupffer cells. For these large liposomes, the rate of uptake by Kupffer cells was rapid, with maximum uptake at around 2 hours after liposome injection. In contrast, parenchymal cells were more effective in taking up small liposomes and the uptake of large liposomes was negligible. In addition, liposomes made with a galactolipid as part of the lipid constituents appeared to have higher affinity to parenchymal cells than liposomes made without the galactolipid. These findings should be of importance in designing suitable liposomes for drug targeting.

Rahman, Y.E.; Cerny, E.A.; Patel, K.R.; Lau, E.H.; Wright, B.J.

1982-01-01

47

Expanding the family of collagen proteins: Recombinant bacterial collagens of varying composition form triple-helices of similar stability  

PubMed Central

The presence of the (Gly-Xaa-Yaa)n open reading frames in different bacteria predicts the existence of an expanded family of collagen-like proteins. To further explore the triple-helix motif and stabilization mechanisms in the absence of hydroxyproline (Hyp), predicted novel collagen-like proteins from Gram-positive and -negative bacteria were expressed in Escherichia coli and characterized. Soluble proteins capable of successful folding and in vitro refolding were observed for collagen proteins from Methylobacterium sp 4-46, Rhodopseudomonas palustris and Solibacter usitatus. In contrast, all protein constructs from Clostridium perfringens were found predominantly in inclusion bodies. However, attachment of a heterologous N-terminal or C-terminal non-collagenous folding domain induced the Clostridium perfringens collagen domain to fold and become soluble. The soluble constructs from different bacteria had typical collagen triple-helical features and showed surprisingly similar thermal stabilities despite diverse amino acid compositions. These collagen-like proteins provide a resource for the development of biomaterials with new properties.

Xu, Chunying; Yu, Zhuoxin; Inouye, Masayori; Brodsky, Barbara; Mirochnitchenko, Oleg

2010-01-01

48

The effect of lipid supplements on ruminal bacteria in continuous culture fermenters varies with the fatty acid composition.  

PubMed

A single flow continuous culture fermenter system was used in this study to investigate the influence of dietary lipid supplements varying in their fatty acid content on the DNA concentration of selected rumen bacteria. Four continuous culture fermenters were used in a 4 × 4 Latin square design with four periods of 10 d each. Treatment diets were fed at 45 g/d (DM basis) in three equal portions during the day. The diets were: 1) control (CON), 2) control with animal fat source (SAT), 3) control with soybean oil (SBO), and 4) control with fish oil (FO). Lipid supplements were added at 3% of diet DM. The concentrations of total volatile fatty acids and acetate were not affected (P>0.05) by lipid supplements. Concentrations of propionate, iso-butyrate, valerate and iso-valerate were highest (P<0.05) with the FO diet compared with the other treatment diets. The concentration of til C18:l (vaccenic acid, VA) in effluents increased (P<0.05) with SBO and FO diets and was highest with the SBO diet. The concentrations of C18:0 in effluents were lowest (P<0.05) for the FO diet compared with the other treatment diets. Concentrations of DNA for Anaerovibrio lipolytica, and Butyrivibrio proteoclasticus in fermenters were similar (P>0.05) for all diets. The DNA concentrations of Butyrivibrio fibrisolvens and Ruminococcus albus in fermenters were lowest (P<0.05) with the FO diet but were similar (P>0.05) among the other treatment diets. Selenomonas ruminantium DNA concentration in fermenters was highest (P<0.05) with the FO diet. In conclusion, SBO had no effect on bacterial DNA concentrations tested in this study and the VA accumulation in the rumen observed on the FO diet may be due in part to FO influence on B. fibrisolvens, R. albus, and S. ruminantium. PMID:21538241

Potu, Ramesh B; AbuGhazaleh, Amer A; Hastings, Darcie; Jones, Karen; Ibrahim, Salam A

2011-04-01

49

Mineral particles of varying composition induce differential chemokine release from epithelial lung cells: importance of physico-chemical characteristics.  

PubMed

Presently, little is known about the potential health effects of mineral particles other than asbestos and quartz. In this study, a human epithelial lung cell line (A549), primary human small airway epithelial cells (SAECs) and primary rat type 2 (T2) cells were exposed to stone quarry particles of two size fractions (<10 and <2.5 microm) from nine different rock samples. The ability to induce the release of chemokines from lung cells was investigated and compared with the particles' mineral and element composition and the amount of soluble elements. The stone particles induced the release of only low levels of interleukin (IL)-8 from A549 cells. In contrast, some of the other particles induced the release of high levels of macrophage inflammatory protein (MIP)-2 from T2 cells, and high levels of IL-8 from SAECs. Differences in particle surface area could account for differences in activity between the <10 and <2.5 microm fractions of six out of the nine rock samples. For two samples the <2.5 microm fraction was most active and for one sample the <10 microm fraction was most active. Content of the mineral plagioclase displayed a strong, negative correlation with the potential to induce MIP-2, whereas the mineral pyroxene was positively correlated with MIP-2 induction. However, neither plagioclase nor pyroxene content was sufficient to explain differences in bioactivity between the particles. No statistically significant correlation was found between the amounts of total or soluble elements and MIP-2 release. In conclusion, the results suggest that mineral particles with a high content of plagioclase have a low potential to induce a pro-inflammatory response. However, a particular mineral or element responsible for eliciting strong increases in chemokine release could not be identified. Thus, at present it appears that analysing mineral and element content is insufficient to predict stone particle bioactivity, and that biological testing is a necessity. PMID:15640311

Ovrevik, J; Myran, T; Refsnes, M; Låg, M; Becher, R; Hetland, R B; Schwarze, P E

2005-04-01

50

Sediment accretion rates and sediment composition in Prairie Pothole wetlands under varying land use practices, Montana, United States  

USGS Publications Warehouse

Increased sedimentation and nutrient cycle changes in Prairie Pothole Region wetlands associated with agriculture threaten the permanence and ecological functionality of these important resources. To determine the effects of land use on sedimentation and nutrient cycling, soil cores were analyzed for cesium-137 (137Cs), lead-210 (210Pb), and potassium-40 (40K) activities; textural composition; organic and inorganic carbon (C); and total nitrogen (N) from twelve wetlands surrounded by cropland, Conservation Reserve Program (CRP) lands, or native prairie uplands. Separate soil cores from nine of these wetlands were also analyzed for phosphorus (P), nitrate (NO3), and ammonium (NH4) concentrations. Wetlands surrounded by cropland had significantly greater linear sediment accretion rates than wetlands surrounded by CRP or native prairie. Linear sediment accretion rates from wetlands surrounded by cropland were 2.7 and 6 times greater than wetlands surrounded by native prairie when calculated from the initial and peak occurrence of 137Cs, respectively, and 0.15 cm y?1 (0.06 in yr?1) greater when calculated from 210Pb. Relative to wetlands surrounded by CRP, linear sediment accretion rates for wetlands surrounded by cropland were 4.4 times greater when calculated from the peak occurrence of 137Cs. No significant differences existed between the linear sediment accretion rates between wetlands surrounded by native prairie or CRP uplands. Wetlands surrounded by cropland had increased clay, P, NO3, and NH4, and decreased total C and N concentrations compared to wetlands surrounded by native prairie. Wetlands surrounded by CRP had the lowest P and NO3 concentrations and had clay, NH4, C, and N concentrations between those of cropland and native prairie wetlands. We documented increased linear sediment accretion rates and changes in the textural and chemical properties of sediments in wetlands with cultivated uplands relative to wetlands with native prairie uplands. These findings demonstrate the value of the CRP at protecting wetland catchments to reduce sedimentation.

Preston, T. M.; Sojda, R. S.; Gleason, R. A.

2013-01-01

51

Varying constants.  

PubMed

We review properties of theories for the variation of gravitation and fine structure 'constants'. We highlight some general features of the cosmological models that exist in these theories with reference to recent quasar data that are consistent with time variation in the fine structure constant since a redshift of 3.5. The behaviour of a simple class of varying-alpha cosmologies is outlined in the light of all the observational constraints. PMID:16147502

Barrow, John D

2005-09-15

52

Strains of Bacillus cereus vary in the phenotypic adaptation of their membrane lipid composition in response to low water activity, reduced temperature and growth in rice starch.  

PubMed

The phenotypic adaptation of membrane lipids in seven strains of the food-poisoning bacterium Bacillus cereus, isolated from Bangladeshi rice, is reported in relation to their ability to grow under conditions of low water activity (a(w)), reduced temperature and the presence of soluble rice starch. The strains have different membrane phospholipid head-group and fatty acyl compositions, and they display individual differences in their responses to both low a(w) and reduced temperature. The extent of the increase in anionic membrane lipids in response to low a(w) varies from strain to strain, is solute specific and in one strain does not occur. Growth is stimulated by the presence of soluble rice starch and results in a large rise in the proportion of diphosphatidylglycerol (DPG) at the expense of phosphatidylglycerol (PG), without any change in the proportion of total anionic phospholipids. Growth at 15 degrees C compared with 37 degrees C increases the proportions of DPG and phosphatidylethanolamine at the expense of PG. At the lower temperature there are changes in phospholipid fatty acyl composition characteristic of those expected to maintain membrane fluidity, including increases in the amount of total branched fatty acids and the anteiso-/iso-branched ratio, and a decrease in the equivalent chain-length, but there are strain differences in how those changes were achieved. In contrast to some other bacilli, there are persistent large increases in the proportions of unsaturated fatty acyl chains in phospholipids during growth at 15 degrees C. PMID:15133101

Haque, Md Anwarul; Russell, Nicholas J

2004-05-01

53

Emotions and calls  

NSDL National Science Digital Library

Birds use different calls to understand each other. Birds can give distress calls and other calls to let other birds know how they feel. Similarly, humans can detect how other humans feel by the tone of voice they use. They can use their hearing abilities to assess the emotions and moods of others.

N/A N/A (None;)

2006-10-08

54

Callings and Organizational Behavior  

ERIC Educational Resources Information Center

Current literature on careers, social identity and meaning in work tends to understate the multiplicity, historical significance, and nuances of the concept of calling(s). In this article, we trace the evolution of the concept from its religious roots into secular realms and develop a typology of interpretations using occupation and religious…

Elangovan, A. R.; Pinder, Craig C.; McLean, Murdith

2010-01-01

55

Tradeoffs in the evolution of frog calls  

Microsoft Academic Search

All biological characteristics are subject to conflicting selection pressures. This is particularly true of those characteristics\\u000a that are subject to sexual selection. The classic example is the peacock’s tail. Others are the calls used by male frogs and\\u000a toads to attract their mates. The forces which have acted in the evolution of these calls are varied and the calls that

A Stanley Rand

1985-01-01

56

When lawyers call clinicians.  

PubMed

Every psychiatrist, psychologist, and psychotherapist gets calls from attorneys from time to time, often with a request involving a patient. Patients sometimes ask their clinicians to become involved in their legal matters. Such calls and requests may sound straightforward, but they are often misleading, incomplete, or misunderstood. One should avoid being reflexively "helpful" when a lawyer calls or a patient makes such a special request. There may be no obligation to respond, or to respond immediately, although subpoenas must not be ignored; promptly contacting an appropriate supervisor, facility risk manager, malpractice insurance carrier, or one's own attorney is often the best course of action. Office staff such as secretaries and receptionists should also be trained and cautioned regarding the principles discussed here. PMID:20644361

Reid, William H

2010-07-01

57

The effect of varying Al2O3 percentage in hydroxyapatite/Al2O3 composite materials: morphological, chemical and cytotoxic evaluation.  

PubMed

Hydroxyapatite (HA) and HA-alumina (HA/Al2O3) composites, with Al2O3 contents of 5, 10, 20, and 30%, were synthesized using a wet precipitation method and sintered at 900 and 1300 degrees C. We investigated the effect of sintering temperature and relative concentration of HA and Al2O3 on the chemical composition, surface morphology, and cytotoxicity of the composite powders. The XRD results show that in the 1300 degrees C composites, HA partially decomposed into CaO which combined with Al2O3 to form different calcium aluminates. For the 900 degrees C composites the CaO phase was not detected, though a Ca/P ratio larger than 1.67 measured by XPS suggests that CaO was present in trace amounts. SEM-EDX analysis indicated that the HA microstructure was affected by the sintering temperature, and this HA is present on the surface of Al2O3 particles. The cytotoxicity of the composites was assessed indirectly using the MTT assay. The short-term effect of leachables was quantified by exposing a L929 mouse fibroblast cell line to the degradation products released by the composites after immersion in the cell culture medium. Degradation products were less toxic to L-929 at lower extract concentrations (10, 50%) than at 100% concentration. Cell viability was also influenced by leachable size. PMID:17584892

Epure, L M; Dimitrievska, S; Merhi, Y; Yahia, L 'H

2007-12-15

58

Call Admission Control for Mobile Multimedia Wireless Networks  

Microsoft Academic Search

Call Admission Control (CAC) policies in mobile cellular wireless networks give priority to handoff requests over new call requests. In the guard channel policy, an integer number of channels are reserved for handoff calls, while the fractional guard channel policy rejects new calls with a probability that varies with the current channel occupancy. The effect of reservations on new and

Sundus Mahmod; Harsha Sirisena; Krzysztof Pawlikowski

59

Lightweight Remote Procedure Call  

Microsoft Academic Search

Lightweight Remote Procedure Call (LRPC) is a com- munication facility designed and optimized for commu- nication between protection domains on the (same ma- chine. In contemporary small-kernel operating systems, ex- isting RPC systems incur an unnecessarily high cost when used for the type of communication that pre- dominates - between protection domains on the same machine. This cost leads system

Brian N. Bershad; Thomas E. Anderson; Edward D. Lazowska; Henry M. Levy

1989-01-01

60

Lightweight remote procedure call  

Microsoft Academic Search

Lightweight Remote Procedure Call (LRPC) is a communication facility designed and optimized for communication between protection domains on the same machine. In contemporary small-kernel operating systems, existing RPC systems incur an unnecessarily high cost when used for the type of communication that predominates—between protection domains on the same machine. This cost leads system designers to coalesce weakly related subsystems into

Brian N. Bershad; Thomas E. Anderson; Edward D. Lazowska; Henry M. Levy

1990-01-01

61

Call of the Wild  

NSDL National Science Digital Library

Objective: Students will evaluate informational text and build background knowledge about the American Author Jack London. Procedures: Click on the links below and read the biographical information about Jack London, the historical time period in which he wrote, and his writing by reading a few excerpts from Call of The Wild, Sea Wolf, and more tales. London is highly demanding on his readers; ...

Whaley, Mrs.

2009-04-19

62

Wake-Up Call.  

ERIC Educational Resources Information Center

Focuses on the artist, Laquita Thomson, whose inspiration are the stars and space. Discusses her series called, "Celestial Happenings: Stars Fell on Alabama." Describes one event that inspired an art work when a meteor crashed into an Alabama home. Includes lessons for various subject areas. (CMK)

Sartorius, Tara Cady

2002-01-01

63

A Call for Professionalism.  

ERIC Educational Resources Information Center

Albert Shanker, President of the American Federation of Teachers (AFT), speaks about the national testing of teachers and calls for the creation of a new and better national examination for new teachers. While members of the AFT have a few differences with some of the current reform proposals, the AFT in general supports the overwhelming majority…

Shanker, Albert

64

Protein Allelic Composition, Dough Rheology, and Baking Characteristics of Flour Mill Streams from Wheat Cultivars with Known and Varied Baking Qualities 1  

Microsoft Academic Search

Cereal Chem. 79(5):720-725 Flour mill streams obtained by milling grain of 10 bread wheat cultivars grown in the Skopje region of Macedonia were analyzed for rheological and breadmaking quality characteristics and for composition of gliadins and HMW-GS. The objective of this study was to examine the relationships between the composition of gluten proteins and bread- making quality, as well as

M. Menkovska; D. Knezevic; M. Ivanoski

2002-01-01

65

Automated call tracking systems  

SciTech Connect

User Services groups are on the front line with user support. We are the first to hear about problems. The speed, accuracy, and intelligence with which we respond determines the user`s perception of our effectiveness and our commitment to quality and service. To keep pace with the complex changes at our sites, we must have tools to help build a knowledge base of solutions, a history base of our users, and a record of every problem encountered. Recently, I completed a survey of twenty sites similar to the National Energy Research Supercomputer Center (NERSC). This informal survey reveals that 27% of the sites use a paper system to log calls, 60% employ homegrown automated call tracking systems, and 13% use a vendor-supplied system. Fifty-four percent of those using homegrown systems are exploring the merits of switching to a vendor-supplied system. The purpose of this paper is to provide guidelines for evaluating a call tracking system. In addition, insights are provided to assist User Services groups in selecting a system that fits their needs.

Hardesty, C.

1993-03-01

66

Influence of varying hydrogen bond strength resulting from compositional variation on the vibration spectra of proton glasses: K1-x(NH4)xH2PO4  

NASA Astrophysics Data System (ADS)

Single crystal neutron diffraction investigation [Choudhury and Chitra, J. Phys. Condense Matter, 25 (2013) 075902] on four mixed crystals with composition (K1-x(NH4)xH2PO4) where x=0.0, 0.29, 0.67, and 1.0 belonging to the potassium dihydrogen phosphate family of hydrogen bonded ferroelectric crystals had revealed that the compositional variation results in subtle structural differences primarily in the hydrogen bonds of these crystals. The study indicated that there is a change in hydrogen bond strengths with the change in crystal composition. Spectral investigation of the same set of four mixed crystals is undertaken with an intention to study the influence of the varying hydrogen bond strength on the vibrational properties of the crystals. Room temperature Raman spectra for all the four crystals are recorded in the range 100-4000 cm-1. This Raman investigation correlates the structural changes observed from neutron diffraction investigations to the changes in the vibration spectra of the crystals. The varying N-H-O hydrogen bond strength in the mixed crystals is found to have an observable effect on the librational frequencies of the molecular components of these crystals. The strong OHO hydrogen bonds in these crystals give rise to four spectral bands in the 1500-3000 cm-1 spectral region; this is in accordance with the theoretical prediction from the tunneling model for the very strong OHO hydrogen bonds. These OHO bonds can be described by a low barrier double well potential; the vibrational energy levels of the potential are split due to quantum tunneling effects. It is observed that the varying OHO hydrogen bond strength of these crystals results in a variation in the splitting of the vibrational energy levels of the hydrogen bond potential. It is attempted to correlate the varying OHO hydrogen bond strength with the expected variation in the freezing temperature with composition of these proton glasses.

Choudhury, Rajul Ranjan; Chitra, R.; Abraham, Geogy J.

2014-07-01

67

The dynamics of top-down and bottom-up effects in food webs of varying prey diversity, composition, and productivity  

Microsoft Academic Search

Prey diversity is thought to mediate the strength of top-down and bottom-up effects, but few experiments directly test this hypothesis. I assembled food webs of bacteria and bacterivorous protist prey in laboratory microcosms with all combinations of five productivity levels, two top predator treatments (present or absent), and three prey compositions. Depauperate food chains contained one of two edible prey

Jeremy W. Fox

2007-01-01

68

Ultradeep 16S rRNA Sequencing Analysis of Geographically Similar but Diverse Unexplored Marine Samples Reveal Varied Bacterial Community Composition  

PubMed Central

Background Bacterial community composition in the marine environment differs from one geographical location to another. Reports that delineate the bacterial diversity of different marine samples from geographically similar location are limited. The present study aims to understand whether the bacterial community compositions from different marine samples harbour similar bacterial diversity since these are geographically related to each other. Methods and Principal Findings In the present study, 16S rRNA deep sequencing analysis targeting V3 region was performed using Illumina bar coded sequencing. A total of 22.44 million paired end reads were obtained from the metagenomic DNA of Marine sediment, Rhizosphere sediment, Seawater and the epibacterial DNA of Seaweed and Seagrass. Diversity index analysis revealed that Marine sediment has the highest bacterial diversity and the least bacterial diversity was observed in Rhizosphere sediment. Proteobacteria, Actinobacteria and Bacteroidetes were the dominant taxa present in all the marine samples. Nearly 62–71% of rare species were identified in all the samples and most of these rare species were unique to a particular sample. Further taxonomic assignment at the phylum and genus level revealed that the bacterial community compositions differ among the samples. Conclusion This is the first report that supports the fact that, bacterial community composition is specific for specific samples irrespective of its similar geographical location. Existence of specific bacterial community for each sample may drive overall difference in bacterial structural composition of each sample. Further studies like whole metagenomic sequencing will throw more insights to the key stone players and its interconnecting metabolic pathways. In addition, this is one of the very few reports that depicts the unexplored bacterial diversity of marine samples (Marine sediment, Rhizosphere sediment, Seawater) and the host associated marine samples (Seaweed and Seagrass) at higher depths from uncharacterised coastal region of Palk Bay, India using next generation sequencing technology.

Karutha Pandian, Shunmugiah

2013-01-01

69

What is called symptom?  

PubMed

There is one concept in medicine which is prominent, the symptom. The omnipresence of the symptom seems, however, not to be reflected by an equally prominent curiosity aimed at investigating this concept as a phenomenon. In classic, traditional or conventional medical diagnostics and treatment, the lack of distinction with respect to the symptom represents a minor problem. Faced with enigmatic conditions and their accompanying labels such as chronic fatigue syndrome, fibromyalgia, medically unexplained symptoms, and functional somatic syndromes, the contestation of the symptom and its origin is immediate and obvious and calls for further exploration. Based on a description of the diagnostic framework encompassing medically unexplained conditions and a brief introduction to how such symptoms are managed both within and outside of the medical clinic, we argue on one hand how unexplained conditions invite us to reconsider and re-think the concept we call a "symptom" and on the other hand how the concept "symptom" is no longer an adequate and necessary fulcrum and must be enriched by socio-cultural, phenomenological and existential dimensions. Consequently, our main aim is to expand both our interpretative horizon and the linguistic repertoire in the face of those appearances we label medically unexplained symptoms. PMID:23877313

Eriksen, Thor Eirik; Risør, Mette Bech

2014-02-01

70

Nectar-carbohydrate production and composition vary in relation to nectary anatomy and location within individual flowers of several species of Brassicaceae  

Microsoft Academic Search

.   Nectar-carbohydrate production and composition were investigated by high-performance liquid chromatography and enzymology\\u000a in nine species from five tribes of the Brassicaceae. In six species (Arabidopsis thaliana (L.) Heynh., Brassica napus L., B. rapa L., Lobularia maritima (L.) Desv., Raphanus sativus L., Sinapis arvensis L.) that produced nectar from both lateral nectaries (associated with the short stamens) and median nectaries

Arthur R. Davis; Jeffrey D. Pylatuik; Joelle C. Paradis; Nicholas H. Low

1998-01-01

71

You Call That Quantitative?  

PubMed Central

Any reasonably modern fluorescence microscope can produce beautiful images of your cells and tissues without too much effort. But would you believe me if I told you that up to half of the images taken on our microscopes are essentially unquantifiable!? Lurking behind those colourful facades are: Lamp/ laser intensity fluctuations (as bad as 20% in a 3-hr session!)Non-uniform illumination across the field-of view (15–30% variations!)Uncorrected background and bleedthroughDark craters on camera surfacesPoor shutter control, leading to varying degrees of photobleaching Despite the fact that these (and other) issues are surprisingly widespread, users of these instruments are blissfully unaware of any problems and will likely go on to analyze the resulting images. I'll present several Case Studies that illustrate the extent of these problems, and then I'll suggest 7 specific steps that users can follow to ensure they get quantitative data from their microscope images.

Jonkman, James

2013-01-01

72

Performance analysis of automatic call distributors with call waiting lamps  

Microsoft Academic Search

In various businesses there is often a need to match incoming calls with agents-for example, airline reservation systems, operator services, and catalog sales. This need is met through use of automatic call distributors (ACD). The simplest and most usual way for an ACD to match calls and agents is first in first out, i.e. the call that has waited the

M. Perry; A. Nilsson

1995-01-01

73

A call to revolution.  

PubMed

Americans will not succeed in containing healthcare costs until they make some radical changes in the way they think about life, death, and the pursuit of good health. This is the contention of Daniel Callahan, who, in his new book, What Kind of Life: The Limits of Medical Progress, calls for a revolution of sorts-a change in the nation's psychological and political foundations. In Callahan's brave new world, limits rather than aspirations, risks rather than benefits, and pitfalls rather than opportunities would be emphasized. Research projects with costly and likely limited social payoffs would be rare; Americans, accustomed to demanding the most advanced technology that medicine has to offer, would have to accept the inevitability of disease and death. Callahan presents an outline for establishing healthcare priorities and rationing services. He frames those priorities within a context of limits on extending longevity and pursuing individual cures. The outline is pyramidal. Fewer people generally would receive health services as they ascend the pyramid's six levels, and the cost per person would rise dramatically. In this milieu, children would have "some priority" over adults, particularly the elderly. PMID:10105573

Grimaldi, P L

1990-01-01

74

Disparity Analysis of Time-Varying Imagery.  

National Technical Information Service (NTIS)

An interactive program (called program DIDA) was developed to perform disparity analysis of time-varying imagery. The program consists of four sections: (1) image operations; (2) interesting point selection; (3) interesting point matching, and (4) image d...

F. D. Cooper

1981-01-01

75

Tailoring the electronic and elastic properties by varying the composition of the CuGa1-xAlxS2 chalcopyrite semiconductor  

NASA Astrophysics Data System (ADS)

The influence of composition and external hydrostatic pressure on the structural, electronic and optical properties of the CuGa1-xAlxS2 (x = 0, 0.25, 0.5, 0.75, 1.0) chalcopyrite semiconductor was analysed by means of the first-principles calculations. Dielectric functions and optical absorption spectra were calculated for all considered aluminum concentrations. The pressure coefficients of the calculated band gaps and the position of the lowest in energy absorption peaks were extracted from the calculated data. One of the main results is that substitution of 25% of gallium by aluminum (thus forming the CuGa0.75Al0.25S2 semiconductor) increases absorption in the visible part of the solar spectrum by about 6%, which can be important for solar cell applications.

Brik, M. G.; Ma, C. G.

2013-07-01

76

Time Varying Feature Data  

NASA Astrophysics Data System (ADS)

The infrastructure to gather, store and access information about our environment is improving and growing rapidly. The increasing amount of information allows us to get a better understanding of the current state of our environment, historical processes and to simulate and predict the future state of the environment. Finer grained spatial and temporal data and more reliable communications make it easier to model dynamic states and ephemeral features. The exchange of information within and across geospatial domains is facilitated through the use of harmonized information models. The Observations & Measurements (O&M) developed through OGC and standardised by ISO is an example of such a cross-domain information model. It is used in many domains, including meteorology, hydrology as well as the emergency management. O&M enables harmonized representation of common metadata that belong to the act of determining the state of a feature property, whether by sensors, simulations or humans. In addition to the resulting feature property value, information such as the result quality but especially the time that the result applies to the feature property can be represented. Temporal metadata is critical to modelling past and future states of a feature. The features, and the semantics of each property, are defined in domain specific Application Schema using the General Feature Model (GFM) from ISO 19109 and usually encoded following ISO 19136. However, at the moment these standards provide only limited support for the representation and handling of time varying feature data. Features like rivers, wildfires or gas plumes have a defined state - for example geographic extent - at any given point in time. To keep track of changes, a more complex model for example using time-series coverages is required. Furthermore, the representation and management of feature property value changes via the service interfaces defined by OGC and ISO - namely: WFS and WCS - would be rather complex. Keeping track of feature property value corrections or even feature (state change) cancellations for auditing purposes is also not easy to achieve. The aviation domain has strong requirements to represent and manage the state of aeronautical features through time. Being able to efficiently encode and manage feature state changes, keeping track of all changes for auditing purposes and being able to determine the future state of an aeronautical feature as currently known to the system are vital for aeronautical applications. In order to support these requirements, the Aeronautical Information Exchange Model (AIXM) which has been developed by the aviation domain is based on the so called AIXM Temporality Model (AIXM-TM). The AIXM-TM defines various rules for modeling, representing and handling the state of aeronautical features through time. This is a promising approach that can be incorporated into the GFM so that ultimately the modeling and management of time varying feature data is supported in an interoperable and harmonized way in all geospatial domains. This presentation gives an introduction to the main concepts of the AIXM-TM. It also shows how the GFM can be extended to support time varying feature data. Finally, the relationship of O&M and time varying features is discussed.

Echterhoff, J.; Simonis, I.; Atkinson, R.

2012-04-01

77

Is alarm calling risky? Marmots avoid calling from risky places  

PubMed Central

Alarm calling is common in many species. A prevalent assumption is that calling puts the vocalizing individual at increased risk of predation. If calling is indeed costly, we need special explanations for its evolution and maintenance. In some, but not all species, callers vocalize away from safety and thus may be exposed to an increased risk of predation. However, for species that emit bouts with one or a few calls, it is often difficult to identify the caller and find the precise location where a call was produced. We analyzed the spatial dynamics of yellow-bellied marmot (Marmota flaviventris) alarm calling using an acoustic localization system to determine the location from which calls were emitted. Marmots almost always called from positions close to the safety of their burrows, and, if they produced more than one alarm call, tended to end their calling bouts closer to safety than they started them. These results suggest that for this species, potential increased predation risk from alarm calling is greatly mitigated and indeed calling may have limited predation costs.

Collier, Travis C.; Blumstein, Daniel T.; Girod, Lewis; Taylor, Charles E.

2010-01-01

78

Composites  

NSDL National Science Digital Library

In this activity, learners explore how composites work by creating and testing their own composite for an imaginary company. This activity shows learners that composites are simply materials that are made up of two or more visibly distinct substances. Use this activity to talk about how composites are everywhere in our lives.

Research, Cornell C.

2003-01-01

79

Call-by-push-value: Decomposing call-by-value and call-by-name  

Microsoft Academic Search

We present the call-by-push-value (CBPV) calculus, which decomposes the typed call-by-value (CBV) and typed call-by-name (CBN) paradigms into fine-grain primitives. On the operational side, we give big-step semantics and a stack machine for CBPV, which leads to a straightforward push\\/pop reading of CBPV programs. On the denotational side, we model CBPV using cpos and, more generally, using algebras for a

Paul Blain Levy

2006-01-01

80

The information that receivers extract from alarm calls in suricates.  

PubMed Central

Field observations and acoustic analyses have shown that suricate (Suricata suricatta) alarm calls vary in their acoustic structure depending on predator type. In this study, we tested whether receivers respond appropriately when hearing a call in the absence of a predator. Although the only way for suricates to escape from predators is to retreat to boltholes, responses to playbacks could be divided into distinct categories. The subjects responded differently to alarm calls given in response to aerial or terrestrial predators and to recruitment calls emitted in response to snakes and deposits on the ground. Suricates also showed rather distinct responses to low, medium and high urgency aerial calls. Differences in the responses were less obvious for different levels of urgency in the terrestrial and recruitment calls. Suricate receivers thus gain information about both the predator type and level of urgency from the acoustic structures of their calls.

Manser, M B; Bell, M B; Fletcher, L B

2001-01-01

81

Face Recognition Under Varying Illumination Using Gradientfaces  

Microsoft Academic Search

In this correspondence, we propose a novel method to extract illumination insensitive features for face recognition under varying lighting called the gradient faces. Theoretical analysis shows gradient faces is an illumination insensitive measure, and robust to different illumination, including uncontrolled, natural lighting. In addition, gradient faces is derived from the image gradient domain such that it can discover underlying inherent

Taiping Zhang; Yuan Yan Tang; Bin Fang; Zhaowei Shang; Xiaoyu Liu

2009-01-01

82

CALL Essentials: Principles and Practice in CALL Classrooms  

ERIC Educational Resources Information Center

Computers and the Internet offer innovative teachers exciting ways to enhance their pedagogy and capture their students' attention. These technologies have created a growing field of inquiry, computer-assisted language learning (CALL). As new technologies have emerged, teaching professionals have adapted them to support teachers and learners in…

Egbert, Joy

2005-01-01

83

Surveys of calling amphibians in North Dakota  

USGS Publications Warehouse

Amphibians have received increased attention in recent years from the scientific community and general public alike. Many populations throughout the world have declined, or have been extirpated, often without an apparent cause. Concern about the status of amphibians has translated into a growing interest in systematic and statistically sound monitoring programs. Several extensive efforts to monitor populations of calling amphibians are in place, and more are under development. Necessary for the design of appropriate surveys is an understanding of the behavior, especially vocalization, of the various species, and how it varies by geographic location and environmental conditions. In 1995 we conducted roadside surveys of calling amphibians along 44 routes in North Dakota. We describe results of that survey, with special attention given to variables that influence detectability of calling amphibians. Unlike similar studies, we accounted for the amount of time observers spent listening for amphibians under different conditions. We found that the optimal conditions for a single survey for North Dakota in that year would be in early June, between the hours of 2300 and 0130, with ambient temperatures above 13 deg. C, and with no rain and little or no wind or moonlight. Multiple surveys in a year would yield better results, of course, especially for the wood frog (Rana sylvatica), which is most active earlier in the season. Studies such as ours should be replicated in space and time to ensure a well-designed survey.

Johnson, D. H.; Batie, R. D.

2001-01-01

84

Constructing the Procedure Call Multigraph  

Microsoft Academic Search

An algorithm for constructing a precise call multigraph for languages that permit procedure parameters, extending the method of B. Ryder for handling recursion, is presented. If it is assumed that there is a constant upper bound on the number of procedure parameters to any procedure in the program, then the algorithm is polynomial in the total number of procedures in

David Callahan; Alan Carle; Mary W. Hall; Ken Kennedy

1990-01-01

85

Varying-{alpha} monopoles  

SciTech Connect

We study static magnetic monopoles in the context of varying-{alpha} theories and show that there is a group of models for which the 't Hooft-Polyakov solution is still valid. Nevertheless, in general static magnetic monopole solutions in varying-{alpha} theories depart from the classical 't Hooft-Polyakov solution with the electromagnetic energy concentrated inside the core seeding spatial variations of the fine-structure constant. We show that Equivalence Principle constraints impose tight limits on the allowed variations of {alpha} induced by magnetic monopoles which confirms the difficulty to generate significant spatial variation of the fine-structure constant found in previous works. This is true even in the most favorable case where magnetic monopoles are the source for these variations.

Menezes, J.; Avelino, P.P.; Santos, C. [Centro de Fisica do Porto e Departamento de Fisica da Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto (Portugal)

2005-11-15

86

Call Performance for a PCS Network  

Microsoft Academic Search

It is well known that, due to the mobility of a portable and limited channel availability, calls of portables may not be completed due to being blocked or terminated during the call initiation or the handover process. The characteristics of the call-completion and call-holding times for both a complete call and an incomplete call are of critical importance for establishing

Yuguang Fang; Imrich Chlamtac; Yi-bing Lin

1997-01-01

87

Composite  

NASA Astrophysics Data System (ADS)

Particle distribution and hot workability of an in situ Al-TiCp composite were investigated. The composite was fabricated by an in situ casting method using the self-propagating high-temperature synthesis of an Al-Ti-C system. Hot-compression tests were carried out, and power dissipation maps were constructed using a dynamic material model. Small globular TiC particles were not themselves fractured, but the clustering and grain boundary segregation of the particles contributed to the cracking of the matrix by causing the debonding of matrix/particle interfaces and providing a crack propagation path. The efficiency of power dissipation increased with increasing temperature and strain rate, and the maximum efficiency was obtained at a temperature of 723 K (450 °C) and a strain rate of 1/s. The microstructural mechanism occurring in the maximum efficiency domain was dynamic recrystallization. The role of particles in the plastic flow and the microstructure evolution were discussed.

Kim, Su-Hyeon; Cho, Young-Hee; Lee, Jung-Moo

2014-06-01

88

Composites  

NASA Astrophysics Data System (ADS)

Ca3Co4O9 is one of the most promising p-type thermoelectric materials because of its high dimensionless figure of merit ZT. However, polycrystalline Ca3Co4O9 ceramics shows lower ZT value than that for single crystal Ca3 Co4O9 due to its higher electrical resistivity ?. Mikami et al. have reported that the addition of Ag to Ca3Co4O9 ceramics could successfully reduce ? and enhance the power factor. On the other hand, Ohtaki et al. reported that a composite structure could be highly effective to reduce ? for ZnO dually doped with Al and Ga. In this work, we tried to enhance the power factor and reduce ? by forming Ca3Co4O9/[Ca2(Co0.65Cu0.35)2O4]0.624CoO2 composite structure. As a result, the ZT value for Ca3Co4O9/[Ca2(Co0.65Cu0.35)2O4]0.624CoO2 composites reached 0.164 at 700 °C, which was 40 % higher than the value for Ca3Co4O9.

Obata, Kohei; Chonan, Yasunori; Komiyama, Takao; Abe, Kazunori; Aoyama, Takashi; Yamaguchi, Hiroyuki; Sugiyama, Shigeaki

2014-06-01

89

Comparison of acid-detergent lignin, alkaline-peroxide lignin, and acid-detergent insoluble ash as internal markers for predicting fecal output and digestibility by cattle offered bermudagrass hays of varying nutrient composition  

PubMed Central

Background The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle offered bermudagrass [Cynodon dactylon (L.) Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows (594?±?35.5 kg) were allocated randomly to 4 hay diets: low (L), medium low (ML), medium high (MH), and high (H) crude protein (CP) concentration (79, 111, 131, and 164 g CP/kg on a DM basis, respectively). Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08:00 and 16:00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake (DMI), DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results Forage DMI was affected by diet (P =?0.02), and DMI from MH and H was greater (P varying nutrient composition. These internal markers may facilitate studies involving large numbers of animals and forages. Results from such studies may be used to develop improved equations to predict energy values of forages based on the relationship of dietary components to digestibility across a wide range of forages.

2014-01-01

90

Blade pitch varying mechanism  

SciTech Connect

A gas turbine engine is described comprising: (a) a stationary member; (b) first and second rotating structures coaxially disposed about the stationary member; (c) an annular gas flowpath coaxial with the first and second rotating structures; (d) first and second rotor blades attached to the first and second rotating structures; (e) forward and aft rows of variable pitch propulsor blades coupled to and disposed radially outwardly of the first and second rotating structures respectively; (f) a first gear coaxially coupled to one of the propulsor blades whereby angular displacement of the first gear about a radius of the rotating structure varies the pitch of the propulsor blade with respect to the rotating structure; (g) a second gear rotatably coupled to the first gear; (h) a third gear rigidly coupled to the second gear; (i) a fourth gear rigidly coupled to the rotating structure and rotatably coupled to the thrid gear, (j) means for eccentrically revolving the second gear and the third gear with respect to the first gear and the fourth gear, respectively, whereby the first gear is angularly displaced with respect to the fourth gear.

Butler, L.

1988-04-19

91

Bridging a High School Science Fair Experience with First Year Undergraduate Research: Using the E-SPART Analyzer to Determine Electrostatic Charge Properties of Compositionally Varied Rock Dust Particles as Terrestrial Analogues to Mars Materials  

NASA Astrophysics Data System (ADS)

More is known about Mars from data collected in 2004. We present particle size and electrostatic data for particles derived from various terrestrial materials to provide analogue studies for what also appears to be present: sedimentary compositions.

Scott, A. G.; Williams, W. J. W.; Mazumder, M. K.; Biris, A.; Srirama, P. K.

2005-03-01

92

Caching function calls using precise dependencies  

Microsoft Academic Search

This paper describes the implementation of a purely func- tional programming language for building software systems. In this language, external tools like compilers and linkers are invoked by function calls. Because some function calls are extremely expensive, it is obviously important to reuse the results of previous function calls whenever possible. Caching a function call requires the language interpreter to

Allan Heydon; Roy Levin; Yuan Yu

2000-01-01

93

Competitive non-preemptive call control  

Microsoft Academic Search

We deal with randomized competitive algorithms for non-preemptive call control on tree-like switching networks. We give an O(log n) competitive algorithm for nonpreemptive call scheduling on trees. We then introduce the complexities of variable call rates, call durations, and arbitrary call benefits, resulting in a polylog competitive algorithm for the combined problem. We also show that many algorithms for similar

Baruch Awerbuch; Yair Bartalt; Amos Fiat; Adi Rosén

1994-01-01

94

[Bioacoustic of the advertisement call of Ceratophrys cranwelli (Anura: Ceratophryidae)].  

PubMed

The advertisement call plays an important role in the life history of anuran amphibians, mainly during the breeding season. Call features represent an important character to discriminate species, and sound emissions are very effective to assure or reinforce genetic incompatibility, especially in the case of sibling species. Since frogs are ectotherms, acoustic properties of their calls will vary with temperature. In this study, we described the advertisement call of C. cranwelli, quantifying the temperature effect on its components. The acoustic emissions were recorded during 2007 using a DAT record Sony TCD-100 with stereo microphone ECM-MS907 Sony and tape TDK DAT-RGX 60. As males emit their calls floating in temporary ponds, water temperatures were registered after recording the advertisement calls with a digital thermometer TES 1300+/-0.1 degreeC. Altogether, 54 calls from 18 males were analyzed. The temporal variables of each advertisement call were measured using oscillograms and sonograms and the analyses of dominant frequency were performed using a spectrogram. Multiple correlation analysis was used to identify the temperature-dependent acoustic variables and the temperature effect on these variables was quantified using linear regression models. The advertisement call of C. cranwelli consists of a single pulse group. Call duration, Pulse duration and Pulse interval decreased with the temperature, whereas the Pulse rate increased with temperature. The temperature-dependent variables were standardized at 25 degreeC according to the linear regression model obtained. The acoustic variables that were correlated with the temperature are the variables which emissions depend on laryngeal muscles and the temperature constraints the contractile properties of muscles. Our results indicated that temperature explains an important fraction of the variability in some acoustic variables (79% in the Pulse rate), and demonstrated the importance of considering the effect of temperature in acoustic components. The results suggest that acoustic variables show geographic variation to compare data with previous works. PMID:23894980

Valetti, Julián Alonso; Salas, Nancy Edith; Martino, Adolfo Ludovico

2013-03-01

95

Potential Paradigms and Possible Problems for CALL.  

ERIC Educational Resources Information Center

Describes three models of CALL (computer assisted language learning) activity--games, the expert system, and the prosthetic approaches. A case is made for CALL development within a more instrumental view of the role of computers. (Author/CB)

Phillips, Martin

1987-01-01

96

Hornbills can distinguish between primate alarm calls.  

PubMed

Some mammals distinguish between and respond appropriately to the alarm calls of other mammal and bird species. However, the ability of birds to distinguish between mammal alarm calls has not been investigated. Diana monkeys (Cercopithecus diana) produce different alarm calls to two predators: crowned eagles (Stephanoaetus coronatus) and leopards (Panthera pardus). Yellow-casqued hornbills (Ceratogymna elata) are vulnerable to predation by crowned eagles but are not preyed on by leopards and might therefore be expected to respond to the Diana monkey eagle alarm call but not to the leopard alarm call. We compared responses of hornbills to playback of eagle shrieks, leopard growls, Diana monkey eagle alarm calls and Diana monkey leopard alarm calls and found that they distinguished appropriately between the two predator vocalizations as well as between the two Diana monkey alarm calls. We discuss possible mechanisms leading to these responses. PMID:15209110

Rainey, Hugo J; Zuberbühler, Klaus; Slater, Peter J B

2004-04-01

97

What Constitutes a Typical Cell Phone Call.  

National Technical Information Service (NTIS)

A total of 21 young people completed a 35-multipart question survey about their use of cell phones. Of them, 15 completed logs of every call for a month and answered over 20 multipart questions about each call (depending on the call), covering a total of ...

J. George P. Green R. Jacob

2004-01-01

98

Anomaly Detection Using Call Stack Information  

Microsoft Academic Search

The call stack of a program execution can be a very good information source for intrusion detection. There is no pri or work on dynamically extracting information from call stack and effectively using it to detect exploits. In this paper, w e propose a new method to do anomaly detection using call stack information. The basic idea is to extract

Henry Hanping Feng; Oleg M. Kolesnikov; Prahlad Fogla; Wenke Lee; Weibo Gong

2003-01-01

99

Calling in Work: Secular or Sacred?  

ERIC Educational Resources Information Center

Recent scholarship indicates that people who view their work as a calling are more satisfied with their work and their lives. Historically, calling has been regarded as a religious experience, although modern researchers frequently have adopted a more expansive and secular conceptualization of calling, emphasizing meaning and personal fulfillment…

Steger, Michael F.; Pickering, N. K.; Shin, J. Y.; Dik, B. J.

2010-01-01

100

Perceiving a Calling, Living a Calling, and Job Satisfaction: Testing a Moderated, Multiple Mediator Model  

ERIC Educational Resources Information Center

The current study examined the relation between perceiving a calling, living a calling, and job satisfaction among a diverse group of employed adults who completed an online survey (N = 201). Perceiving a calling and living a calling were positively correlated with career commitment, work meaning, and job satisfaction. Living a calling moderated…

Duffy, Ryan D.; Bott, Elizabeth M.; Allan, Blake A.; Torrey, Carrie L.; Dik, Bryan J.

2012-01-01

101

An empirical analysis of the corporate call decision  

NASA Astrophysics Data System (ADS)

In this thesis we provide insights into the behavior of financial managers of utility companies by studying their decisions to redeem callable preferred shares. In particular, we investigate whether or not an option pricing based model of the call decision, with managers who maximize shareholder value, does a better job of explaining callable preferred share prices and call decisions than do other models of the decision. In order to perform these tests, we extend an empirical technique introduced by Rust (1987) to include the use of information from preferred share prices in addition to the call decisions. The model we develop to value the option embedded in a callable preferred share differs from standard models in two ways. First, as suggested in Kraus (1983), we explicitly account for transaction costs associated with a redemption. Second, we account for state variables that are observed by the decision makers but not by the preferred shareholders. We interpret these unobservable state variables as the benefits and costs associated with a change in capital structure that can accompany a call decision. When we add this variable, our empirical model changes from one which predicts exactly when a share should be called to one which predicts the probability of a call as the function of the observable state. These two modifications of the standard model result in predictions of calls, and therefore of callable preferred share prices, that are consistent with several previously unexplained features of the data; we show that the predictive power of the model is improved in a statistical sense by adding these features to the model. The pricing and call probability functions from our model do a good job of describing call decisions and preferred share prices for several utilities. Using data from shares of the Pacific Gas and Electric Co. (PGE) we obtain reasonable estimates for the transaction costs associated with a call. Using a formal empirical test, we are able to conclude that the managers of the Pacific Gas and Electric Company clearly take into account the value of the option to delay the call when making their call decisions. Overall, the model seems to be robust to tests of its specification and does a better job of describing the data than do simpler models of the decision making process. Limitations in the data do not allow us to perform the same tests in a larger cross-section of utility companies. However, we are able to estimate transaction cost parameters for many firms and these do not seem to vary significantly from those of PGE. This evidence does not cause us to reject our hypothesis that managerial behavior is consistent with a model in which managers maximize shareholder value.

Carlson, Murray Dean

102

Effect of Varying CO2 Partial Pressure on Photosynthesis and on Carbon Isotope Composition of Carbon-4 of Malate from the Crassulacean Acid Metabolism Plant Kalanchoë daigremontiana Hamet et Perr. 1  

PubMed Central

Intact leaves of Kalanchoë daigremontiana were exposed to CO2 partial pressures of 100, 300, and 1000 microbars. Malic acid was extracted, purified, and degraded in order to obtain isotopic composition of carbon-1 and carbon-4. From these data, it is possible to calculate the carbon isotope composition of newly fixed carbon in malate. In all three treatments, the isotopic composition of newly introduced carbon is the same as that of the CO2 source and is independent of CO2 partial pressures over the range tested. Comparison with numerical models described previously (O'Leary 1981 Phytochemistry 20: 553-567) indicates that we would expect carbon 4 of malate to be 4‰ more negative than source CO2 if diffusion is totally limiting or 7‰ more positive than source CO2 if carboxylation is totally limiting. Our results demonstrate that stomatal aperture adjusts to changing CO2 partial pressures and maintains the ratio of diffusion resistance to carboxylation resistance approximately constant. In this study, carboxylation and diffusion resistances balance so that essentially no fractionation occurs during malate synthesis. Gas exchange studies of the same leaves from which malate was extracted show that the extent of malate synthesis over the whole night is nearly independent of CO2 partial pressure, although there are small variations in CO2 uptake rate. Both the gas exchange and the isotope studies indicate that the ratio of external to internal CO2 partial pressure is the same in all three treatments. Inasmuch as a constant ratio will result in constant isotope fractionation, this observation may explain why plants in general have fairly invariable 13C contents, despite growing under a variety of environmental conditions.

Holtum, Joseph A. M.; O'Leary, Marion H.; Osmond, C. Barry

1983-01-01

103

Compositional C++: Compositional Parallel Programming  

Microsoft Academic Search

A compositional parallel program is a program constructed by composing component programs in parallel, where the composed program inherits properties of its components. In this paper, we describe a small extension of C++ called Compositional C++ or CC++ which is an object-oriented notation that supports compositional parallel programming. CC++ integrates different paradigms of parallel programming: data-parallel, task-parallel and object-parallel paradigms;

K. Mani Chandy; Carl Kesselman

1992-01-01

104

Varying /c and particle horizons  

NASA Astrophysics Data System (ADS)

We explore what restrictions may impose the second law of thermodynamics on varying speed of light theories. We find that the attractor scenario solving the flatness problem is consistent with the generalized second law at late time.

Chimento, L. P.; Jakubi, A. S.; Pavón, D.

2001-05-01

105

Development and Validation of the Calling and Vocation Questionnaire (CVQ) and Brief Calling Scale (BCS)  

ERIC Educational Resources Information Center

Research on work as a calling is limited by measurement concerns. In response, the authors introduce the multidimensional Calling and Vocation Questionnaire (CVQ) and the Brief Calling scale (BCS), instruments assessing presence of, and search for, a calling. Study 1 describes CVQ development using exploratory and confirmatory factor analysis…

Dik, Bryan J.; Eldridge, Brandy M.; Steger, Michael F.; Duffy, Ryan D.

2012-01-01

106

Staffing a call center with interactive voice response units and impatient calls  

Microsoft Academic Search

A call center consists of telephone trunk lines, a switching machine known as the automatic call distributor (ACD), an interactive voice recording unit (IVRU), and telephone sales agents. Calls enter the center whenever a trunk line is available; otherwise it is lost. Once a trunk line is seized, the call is instructed to choose among several options provided by the

Jinting Wang; Raj Srinivasan

2008-01-01

107

Calling in the Face of Danger  

Microsoft Academic Search

Birds raise their young under constant risk of predation, which shapes how parents and young communicate acoustically. Nestling begging calls extract care from parents but expose them to eavesdropping by predators, which selects for cryptic signal design. However, for largely unknown reasons, nestlings often call even when parents are absent and thus unavailable for defense. Nestlings can give distress and

Robert D. Magrath; Tonya M. Haff; Andrew G. Horn; Marty L. Leonard

2010-01-01

108

Promotion in Call Centres: Opportunities and Determinants  

ERIC Educational Resources Information Center

Purpose: The purpose of this paper is to examine the quality of jobs in call centres by focusing on the opportunities for promotion in this sector. More specifically, the research questions focus on discovering whether promotion is common practise in the call centre sector and on identifying the factors that affect this.…

Gorjup, Maria Tatiana; Valverde, Mireia; Ryan, Gerard

2008-01-01

109

Call admission control in DCA wireless network  

Microsoft Academic Search

A novel call admission control (CAC) scheme based on dynamic channel allocation (DCA) is proposed for cellular networks. The scheme combines the advantage of high channel availability of DCA with quality of service guarantees of CAC. Our scheme uses statistical bandwidth reservation for handoff events. A new call is rejected if the probability of the required bandwidth exceeds the available

Wong Yiu Ming; J. Misic; S. T. Chanson

1998-01-01

110

CALL for Beginners: A Case Study.  

ERIC Educational Resources Information Center

Provides a case study of a computer-assisted language learning (CALL) program for beginning learners of Spanish at the University of Bradford, England. The pros and cons of various software used in the program, as well student attitudes toward CALL, are discussed. (six references) (MDM)

White, Anne M.; Palfreyman, Rachel

1994-01-01

111

ALG: Automated Genotype Calling of Luminex Assays  

Microsoft Academic Search

Single nucleotide polymorphisms (SNPs) are the most commonly used polymorphic markers in genetics studies. Among the different platforms for SNP genotyping, Luminex is one of the less exploited mainly due to the lack of a robust (semi-automated and replicable) freely available genotype calling software. Here we describe a clustering algorithm that provides automated SNP calls for Luminex genotyping assays. We

Mathieu Bourgey; Mathieu Lariviere; Chantal Richer; Daniel Sinnett

2011-01-01

112

Eliminating Virtual Function Calls in C++ Programs  

Microsoft Academic Search

We have designed and implemented an optimizing source-to- source C++ compiler that reduces the frequency of virtual function calls. Our prototype implementation demonstrates the value of OO-specific optimization for C++. Despite some limitations of our system, and despite the low frequency of virtual function calls in some of the programs, optimization improves the performance of a suite of large C++

Gerald Aigner; Urs Hölzle

1996-01-01

113

Dynamic Call Admission Control in ATM Networks  

Microsoft Academic Search

The authors present dynamic call admission control using the distribution of the number of cells arriving during the fixed interval. This distribution is estimated from the measured number of cells arriving at the output buffer during the fixed interval and traffic parameters specified by users. Call acceptance is decided on the basis of online evaluation of the upper bound of

Hiroshi Saito; Kohei Shiomoto

1991-01-01

114

Policy support for H.323 call handling  

Microsoft Academic Search

The need for policies to control calls is justified by the changing face of communications. An overview is given of a general architecture and language for policies. It is then shown how these are adapted for control of calls using the H.323 multimedia communications standard. Policy support for H.323 was created by extending an open-source gatekeeper. The core policy language

Tingxue Huang; Kenneth J. Turner

2005-01-01

115

Using Software Design Methods in CALL  

ERIC Educational Resources Information Center

The phrase "software design" is not one that arouses the interest of many CALL practitioners, particularly those from a humanities background. However, software design essentials are simply logical ways of going about designing a system. The fundamentals include modularity, anticipation of change, generality and an incremental approach. While CALL

Ward, Monica

2006-01-01

116

Using software design methods in CALL  

Microsoft Academic Search

The phrase ‘software design’ is not one that arouses the interest of many CALL practitioners, particularly those from a humanities background. However, software design essentials are simply logical ways of going about designing a system. The fundamentals include modularity, anticipation of change, generality and an incremental approach. While CALL researchers and developers might consider software design as something that is

Monica Ward

2006-01-01

117

Call-by-name, call-by-value, call-by-need and the linear lambda calculus  

Microsoft Academic Search

Girard described two translations of intuitionistic logic into linear logic, one where A !B maps to (!A) \\\\Gammaffi B, and another where it maps to !(A \\\\Gammaffi B). We detail the action ofthese translations on terms, and show that the first corresponds to a call-by-name calculus,while the second corresponds to call-by-value. We further show that if the target of thetranslation

John Maraist; Martin Odersky; David N. Turner; Philip Wadler

1995-01-01

118

Time-Varying Contour Topology  

PubMed Central

The contour tree has been used to compute the topology of isosurfaces, generate a minimal seed set for accelerated isosurface extraction, and provide a user interface to segment individual contour components in a scalar field. In this paper, we extend the benefits of the contour tree to time-varying data visualization. We define temporal correspondence of contour components and describe an algorithm to compute the correspondence information in time-dependent contour trees. A graph representing the topology changes of time-varying isosurfaces is constructed in real-time for any selected isovalue using the precomputed correspondence information. Quantitative properties, such as surface area and volume of contour components, are computed and labeled on the graph. This topology change graph helps users to detect significant topological and geometric changes in time-varying isosurfaces. The graph is also used as an interactive user interface to segment, track. and visualize the evolution of any selected contour components over time.

Sohn, Bong-Soo; Bajaj, Chandrajit

2009-01-01

119

A scatter search algorithm for stacking sequence optimisation of laminate composites  

Microsoft Academic Search

This paper explores the metaheuristic approach called scatter search for lay-up sequence optimisation of laminate composite panels. Scatter search is an evolutionary method that has recently been found to be promising for solving combinatorial optimisation problems. The scatter search framework is flexible and allows the development of alternative implementations with varying degree of sophistication. The main objective of this paper

A. Rama Mohan Rao; N. Arvind

2005-01-01

120

INCORPORATING MANUFACTURING TOLERANCES IN NEAR-OPTIMAL DESIGN OF COMPOSITE STRUCTURES  

Microsoft Academic Search

When a composite structure is manufactured the design variables in the produced structure may vary from the intended design. These variations are called manufacturing tolerances. When optimization is used, the optimal design is often on an active constraint. This may cause the produced structure to fail, even though the variations from the intended design are within tolerances. In this paper

BIRNA P. KRISTINSDOTTIR; ZELDA B. ZABINSKY; MARK E. TUTTLE; TIBOR CSENDES

1996-01-01

121

Audience effects in chimpanzee copulation calls  

PubMed Central

Audience effects arise when the signaling behavior of animals is affected by the presence of others. Whilst this phenomenon has been documented in numerous animal species, very little research has addressed what effect the listening audience has in the mating context. In this article we discuss our recent findings that the production of chimpanzee copulation calls is effected by the presence of potentially eavesdropping females and males. We relate these results to understanding the function of primate copulation calls in addition to what more they can tell us about the cognitive processes underlying primate call production.

Zuberbuhler, Klaus

2009-01-01

122

Russian Prime Minister Calls the Station Crew  

NASA Video Gallery

Russian Prime Minister Vladimir Putin called the International Space Station from the Russian Mission Control Center in Korolev, Russia, on Jan. 11, 2011. Putin also offered his condolences to ISS ...

123

Segmental structure in banded mongoose calls  

PubMed Central

In complex animal vocalizations, such as bird or whale song, a great variety of songs can be produced via rearrangements of a smaller set of 'syllables', known as 'phonological syntax' or 'phonocoding' However, food or alarm calls, which function as referential signals, were previously thought to lack such combinatorial structure. A new study of calls in the banded mongoose Mungos mungo provides the first evidence of phonocoding at the level of single calls. The first portion of the call provides cues to the identity of the caller, and the second part encodes its current activity. This provides the first example known in animals of something akin to the consonants and vowels of human speech. See research article http://www.biomedcentral.com/1741-7007/10/97

2012-01-01

124

Genotype calling for the Illumina platform.  

PubMed

Genome-wide association studies have been made possible because of advancements in the design of genotyping technologies to assay a million or more single nucleotide polymorphisms (SNPs) simultaneously. This has resulted in the introduction of automated and unsupervised statistical approaches for translating the probe hybridization intensities into the actual genotype calls. This chapter aims to provide an introduction to this process of genotype calling, highlighting in particular the design and approach used for the Illumina BeadArray platforms that are commonly used in large-scale genetic studies. The chapter also provides detailed instructions for preparing the input files required as well as the actual Linux commands and options to execute the ILLUMINUS software. Finally, it concludes with a brief exposition on the different outcomes from genotype calling and the use of perturbation analysis for identifying SNPs with erroneous genotype calls. PMID:22307718

Teo, Yik Ying

2012-01-01

125

78 FR 76218 - Rural Call Completion  

Federal Register 2010, 2011, 2012, 2013

...have collaborated to propose industry solutions. For example, in...potential solutions. In 2012, the Alliance for Telecommunications Industry Solutions (ATIS) released...standards and practices of the industry relevant to ensuring call...

2013-12-17

126

OIG advisory opinion clarifies some call issues.  

PubMed

Although the advisory opinion issued by the Department of Health and Human Services' Office of Inspector General (OIG) specifically states it only applies to the pay-for-call arrangement at one hospital, experts say the ED manager can use the opinion to establish bench-marks for their own on-call arrangements. * At the very least, the OIG has made it clear that paying for on-call coverage is not in and of itself a violation of any statutes. * Any per diem rates paid to ensure that specialists agree to take call must be "reasonable" and meet "fair market value." * The fact that the specialists also may be paid for the services they provide may not necessarily mean your arrangement is improper. PMID:18074956

2007-11-01

127

ALG: Automated Genotype Calling of Luminex Assays  

PubMed Central

Single nucleotide polymorphisms (SNPs) are the most commonly used polymorphic markers in genetics studies. Among the different platforms for SNP genotyping, Luminex is one of the less exploited mainly due to the lack of a robust (semi-automated and replicable) freely available genotype calling software. Here we describe a clustering algorithm that provides automated SNP calls for Luminex genotyping assays. We genotyped 3 SNPs in a cohort of 330 childhood leukemia patients, 200 parents of patient and 325 healthy individuals and used the Automated Luminex Genotyping (ALG) algorithm for SNP calling. ALG genotypes were called twice to test for reproducibility and were compared to sequencing data to test for accuracy. Globally, this analysis demonstrates the accuracy (99.6%) of the method, its reproducibility (99.8%) and the low level of no genotyping calls (3.4%). The high efficiency of the method proves that ALG is a suitable alternative to the current commercial software. ALG is semi-automated, and provides numerical measures of confidence for each SNP called, as well as an effective graphical plot. Moreover ALG can be used either through a graphical user interface, requiring no specific informatics knowledge, or through command line with access to the open source code. The ALG software has been implemented in R and is freely available for non-commercial use either at http://alg.sourceforge.net or by request to mathieu.bourgey@umontreal.ca

Bourgey, Mathieu; Lariviere, Mathieu; Richer, Chantal; Sinnett, Daniel

2011-01-01

128

ALG: automated genotype calling of Luminex assays.  

PubMed

Single nucleotide polymorphisms (SNPs) are the most commonly used polymorphic markers in genetics studies. Among the different platforms for SNP genotyping, Luminex is one of the less exploited mainly due to the lack of a robust (semi-automated and replicable) freely available genotype calling software. Here we describe a clustering algorithm that provides automated SNP calls for Luminex genotyping assays. We genotyped 3 SNPs in a cohort of 330 childhood leukemia patients, 200 parents of patient and 325 healthy individuals and used the Automated Luminex Genotyping (ALG) algorithm for SNP calling. ALG genotypes were called twice to test for reproducibility and were compared to sequencing data to test for accuracy. Globally, this analysis demonstrates the accuracy (99.6%) of the method, its reproducibility (99.8%) and the low level of no genotyping calls (3.4%). The high efficiency of the method proves that ALG is a suitable alternative to the current commercial software. ALG is semi-automated, and provides numerical measures of confidence for each SNP called, as well as an effective graphical plot. Moreover ALG can be used either through a graphical user interface, requiring no specific informatics knowledge, or through command line with access to the open source code. The ALG software has been implemented in R and is freely available for non-commercial use either at http://alg.sourceforge.net or by request to mathieu.bourgey@umontreal.ca. PMID:21573116

Bourgey, Mathieu; Lariviere, Mathieu; Richer, Chantal; Sinnett, Daniel

2011-01-01

129

Varying prior information in Bayesian inversion  

NASA Astrophysics Data System (ADS)

Bayes' rule is used to combine likelihood and prior probability distributions. The former represents knowledge derived from new data, the latter represents pre-existing knowledge; the Bayesian combination is the so-called posterior distribution, representing the resultant new state of knowledge. While varying the likelihood due to differing data observations is common, there are also situations where the prior distribution must be changed or replaced repeatedly. For example, in mixture density neural network (MDN) inversion, using current methods the neural network employed for inversion needs to be retrained every time prior information changes. We develop a method of prior replacement to vary the prior without re-training the network. Thus the efficiency of MDN inversions can be increased, typically by orders of magnitude when applied to geophysical problems. We demonstrate this for the inversion of seismic attributes in a synthetic subsurface geological reservoir model. We also present results which suggest that prior replacement can be used to control the statistical properties (such as variance) of the final estimate of the posterior in more general (e.g., Monte Carlo based) inverse problem solutions.

Walker, Matthew; Curtis, Andrew

2014-06-01

130

Time varying Hierarchical Archimedean Copulae  

Microsoft Academic Search

There is increasing demand for models of time-varying and non-Gaussian dependencies for mul- tivariate time-series. Available models suffer from the curse of dimensionality or restrictive assumptions on the parameters and the distribution. A promising class of models are the hierarchical Archimedean copulae (HAC) that allow for non-exchangeable and non-Gaussian dependency structures with a small number of parameters. In this paper

Wolfgang Karl Härdle; Ostap Okhrin; Yarema Okhrin

2010-01-01

131

Close-Call Action Log Form  

NASA Technical Reports Server (NTRS)

"Close Call Action Log Form" ("CCALF") is the name of both a computer program and a Web-based service provided by the program for creating an enhanced database of close calls (in the colloquial sense of mishaps that were avoided by small margins) assigned to the Center Operations Directorate (COD) at Johnson Space Center. CCALF provides a single facility for on-line collaborative review of close calls. Through CCALF, managers can delegate responses to employees. CCALF utilizes a pre-existing e-mail system to notify managers that there are close calls to review, but eliminates the need for the prior practices of passing multiple e-mail messages around the COD, then collecting and consolidating them into final responses: CCALF now collects comments from all responders for incorporation into reports that it generates. Also, whereas it was previously necessary to manually calculate metrics (e.g., numbers of maintenance-work orders necessitated by close calls) for inclusion in the reports, CCALF now computes the metrics, summarizes them, and displays them in graphical form. The reports and all pertinent information used to generate the reports are logged, tracked, and retained by CCALF for historical purposes.

Spuler, Linda M.; Ford, Patricia K.; Skeete, Darren C.; Hershman, Scot; Raviprakash, Pushpa; Arnold, John W.; Tran, Victor; Haenze, Mary Alice

2005-01-01

132

Determination of optimal call admission control policy in wireless networks  

Microsoft Academic Search

This paper investigates the optimal call admission control (CAC) policy for non-priority scheme (NPS) and reserved channel scheme (RCS) in wireless networks, respectively. Both new call and handoff call arrival processes are assumed to be Poisson processes, and the call holding times are exponentially distributed with different rate for new call and handoff calls. Admitting each call would bring a

Wenlong Ni; Wei Li; Mansoor Alam

2009-01-01

133

Speech privacy in customer service call centers  

NASA Astrophysics Data System (ADS)

Customer service call centers are a special type of open plan office with different design considerations and different acoustical goals. Workers want a high degree of visual and verbal contact with adjacent members of their team, but customers do not want to hear crosstalk from other conversations. Achieving the correct balance between these conflicting goals is a challenge for the architect and acoustic consultant. This paper will present several case studies of different call centers with acoustic measurements, user comments, and other subjective assessment methods.

Foulkes, Timothy

2005-09-01

134

Wireless world widens nurse call options.  

PubMed

With wireless technology now an integral part of all our lives, and miniaturisation of computing power having made even hand-held portable devices such as mobile phones powerful tools in their own right, HEJ editor, Jonathan Baillie, spoke to specialist in wireless nurse call systems, Courtney-Thorne, to discuss some of its key recent product innovations, and see what impact it feels developments such as 'cloud' technology will have on the bringing of more technology into the nurse call sector as 'nurse and carer tools'. PMID:24516936

Baillie, Jonathan

2014-01-01

135

Model-based automated detection of echolocation calls using the link detector.  

PubMed

The link detector combines a model-based spectral peak tracker with an echo filter to detect echolocation calls of bats. By processing calls in the spectrogram domain, the links detector separates calls that overlap in time, including call harmonics and echoes. The links detector was validated by using an artificial recording environment, including synthetic calls, atmospheric absorption, and echoes, which provided control of signal-to-noise ratio and an absolute ground truth. Maximum hit rate (2% false positive rate) for the links detector was 87% compared to 1.5% for a spectral peak detector. The difference in performance was due to the ability of the links detector to filter out echoes. Detection range varied across species from 13 to more than 20 m due to call bandwidth and frequency range. Global features of calls detected by the links detector were compared to those of synthetic calls. The error in all estimates increased as the range increased, and estimates of minimum frequency and frequency of most energy were more accurate compared to maximum frequency. The links detector combines local and global features to automatically detect calls within the machine learning paradigm and detects overlapping calls and call harmonics in a unified framework. PMID:18646980

Skowronski, Mark D; Fenton, M Brock

2008-07-01

136

Business roundtable calls for smarter regulation''  

Microsoft Academic Search

The Business Roundtable has decided that if industry can reengineer itself, the government can do the same to the regulatory process. Late last month, the Washington, D.C. based lobbying group issued a white paper calling for a more rational approach to government regulation of industry. The white paper, titled Toward Smarter Regulation'', was sparked by the increasing cost to companies

Storck

1994-01-01

137

Modeling Learning Processes in Lexical CALL.  

ERIC Educational Resources Information Center

Studies the performance of a novice Spanish student using a Computer-assisted language learning (CALL) system designed for vocabulary enlargement. Results indicate that introspective evidence may be used to validate performance data within a theoretical framework that characterizes the learning approach as "surface" or "deep." (25 references)…

Goodfellow, Robin; Laurillard, Diana

1994-01-01

138

Optimized call admission control in wireless networks  

Microsoft Academic Search

Traditional traffic rate regulation\\/degradation schemes in call admission control (CAC) seldom take rate degradation optimization into consideration, thus can not obtain the perfect grade of service (GoS) in session layer. In this paper, we propose an enhanced rate degradation CAC (ERDCAC) scheme in multimedia wireless networks, which is an extension and optimization of the rate regulation CAC scheme. We introduce

Shengdong Xie; Meng Wu

2008-01-01

139

Call admission control in wireless multimedia networks  

Microsoft Academic Search

This paper addresses the call admission control problem for the multimedia services that characterize the third generation of wireless networks. In the proposed model each cell has to serve a variety of classes of requests that differ in their traffic parameters, bandwidth requirements and in the priorities while ensuring proper quality of service levels to all of them. A semi

Novella Bartolini; Imrich Chlanitac

2002-01-01

140

What is This Work Called Teaching?  

ERIC Educational Resources Information Center

In discussing the work of teachers, this paper highlights two books, William Ayers's "To Become a Teacher" and David Hansen's "The Call to Teach," examining the philosophical roots of their analyses; how they define and characterize teaching and its place in public and private spheres; and what metaphors shape and define their visions of teachers…

Irwin-DeVitis, Linda; DeVitis, Joseph L.

1998-01-01

141

Web-Based CALL to Listening Comprehension  

ERIC Educational Resources Information Center

This study investigated effectiveness of Web-based CALL on listening comprehension. Both students' academic performance and attitudes were examined. T-tests were used to analyze the results of students' academic performance. Descriptive statistics interpreted students' attitudes toward this learning. Students' participation was also recorded.…

Chen, Li-Mei; Zhang, Ruiming

2010-01-01

142

Easy system call tracing for Plan 9.  

SciTech Connect

Tracing system calls makes debugging easy and fast. On Plan 9, traditionally, system call tracing has been implemented with acid. New systems do not always implement all the capabilities needed for Acid, particularly the ability to rewrite the process code space to insert breakpoints. Architecture support libraries are not always available for Acid, or may not work even on a supported architecture. The requirement that Acid's libraries be available can be a problem on systems with a very small memory footprint, such as High Performance Computing systems where every Kbyte counts. Finally, Acid tracing is inconvenient in the presence of forks, which means tracing shell pipelines is particularly troublesome. The strace program available on most Unix systems is far more convenient to use and more capable than Acid for system call tracing. A similar system on Plan 9 can simplify troubleshooting. We have built a system calling tracing capability into the Plan 9 kernel. It has proven to be more convenient than strace in programming effort. One can write a shell script to implement tracing, and the C code to implement an strace equivalent is several orders of magnitude smaller.

Minnich, Ronald G.

2010-09-01

143

Distributed call processing for personal communications services  

Microsoft Academic Search

The authors present a control architecture, procedures, and a signaling system to support advanced personal communication services (PCS). They describe the current cellular system architecture, and its algorithms and data management schemes for providing services. They present review how current cellular systems operate with a focus on mobility management and call and connection control. The benefits of this architecture include

Thomas F. La Porta; Malathi Veeraraghavan; Philip A. Treventi; Ramachandran Ramjee

1995-01-01

144

gprof: a Call Graph Execution Profiler  

Microsoft Academic Search

Large complex programs are composed of many small routines that implement abstractions for the routines that call them. To be useful, an execution profiler must attribute execution time in a way that is significant for the logical structure of a program as well as for its textual decomposition. This data must then be displayed to the user in a convenient

Susan L. Graham; Peter B. Kessler; Marshall K. McKusick

1982-01-01

145

Why We Like to Call Ourselves Latinas  

ERIC Educational Resources Information Center

This article discusses the complex and subtle reasons why many people of Spanish-speaking ancestry, both Latin Americans and Spaniards, like to call themselves Latinos. Among other things, this word, coined by the Mediterranean countries to resist Anglo dominance in the 19th century, is currently being used by people of Spanish-speaking ancestry…

Gonzlez, Christina; Gandara, Patricia

2005-01-01

146

HARDROCK MINING 2002 CALL FOR ABSTRACTS: ANNOUNCEMENT  

EPA Science Inventory

NRMRL-CIN-1539 Martin, A. Hardrock Mining 2002 Call for Abstracts. Hardrock Mining 2002, Westminster, CO, 5/7-9/2002. EPA/625/F- 01/003. and future environmental issues shaping the mining industry with emphasis on case study analysis and technology verification. This flyer is a...

147

A Call for School Counseling Practitioner Research  

ERIC Educational Resources Information Center

Despite the repeated call to increase the number of practitioner research manuscripts being published in counseling publications, practitioner research accounts for less than five percent of all manuscripts published. This article describes the challenges faced by practitioners seeking to publish their research, defines practitioner research, and…

Kaffenberger, Carol J.

2012-01-01

148

Call admission control schemes: a review  

Microsoft Academic Search

Over the last few years, a substantial number of call admission control (CAC) schemes have been proposed for ATM networks. We review the salient features of some of these algorithms. Also, we quantitatively compare the performance of three of these schemes

Harry G. Perros; Khaled M. Elsayed

1996-01-01

149

Hemodialysis access failure: A call to action  

Microsoft Academic Search

Hemodialysis access failure: A call to action. Recent evidence suggests that the cost as well as the morbidity associated with the maintenance of hemodialysis access is increasing rapidly; currently, the cost exceeds 1 billion dollars and access related hospitalization accounts for 25% of all hospital admissions in the U.S.A. This increase in cost and morbidity has been associated with several

Raymond Hakim; Jonathan Himmelfarb

1998-01-01

150

Calling Careers: Overview and Accompanying Teachers' Manual.  

ERIC Educational Resources Information Center

CALLING CAREERS is a televised series of fifteen 20-minute lessons intended to acquaint fourth through eighth grade students with twelve vocational clusters and to demonstrate the opportunities contained within them, the relationships between them, and the personal characteristics and work habits they require. The series also demonstrates how jobs…

Pinson, Nancy M.

151

CALL FOR ABSTRACTS - PIT LAKES 2004  

EPA Science Inventory

This call for abstracts is for the 11/16-18/2004 Pit Lakes 2004 meeting held in Reno, NV. This conference will provide a forum for the exchange of scientific information on current domestic and international pit lake approaches, including pit lakes from arid and wet regions throu...

152

Components of a CALL Teacher Training Workshop.  

ERIC Educational Resources Information Center

A 2-day teacher training workshop in computer-assisted language learning (CALL) designed for teachers of English as a Second Language (ESL) is described. Program objectives included the following: awareness of computer uses consistent with current principles of second language learning; direct experience with computers, emphasizing what can go…

Baltra, Armando

153

Emotions analysis of speech for call classification  

Microsoft Academic Search

Most existing research in the area of emotions recognition has focused on short segments or utterances of speech. In this paper we propose a machine learning system for classifying the overall sentiment of long conversations as being Positive or Negative. Our system has three main phases, first it divides a call into short segments, second it applies machine learning to

Esraa Ali Hassan; Neamat El Gayar; M. Ghanem Moustafa

2010-01-01

154

Relabeling the medications we call antidepressants.  

PubMed

This paper raises the question about whether the data on the medications we call antidepressants justify the label of antidepressant. The authors argue that a true antidepressant should be clearly superior to placebo, should offer a risk/benefit balance that exceeds that of alternative treatments, should not increase suicidality, should not increase anxiety and agitation, should not interfere with sexual functioning, and should not increase depression chronicity. Unfortunately, these medications appear to fall short on all of these dimensions. Many of the "side effects" of these medications have larger effect sizes than the antidepressant effect size. To call these medications antidepressants may make sense from a marketing standpoint but may be misleading from a scientific perspective. Consumers deserve a label that more accurately reflects the data on the largest effects and helps them understand the range of effects from these medications. In other words, it may make just as much sense to call these medications antiaphrodisiacs as antidepressants because the negative effects on libido and sexual functioning are so common. It can be argued that a misleading label may interfere with our commitment to informed consent. Therefore, it may be time to stop calling these medications antidepressants. PMID:24278764

Antonuccio, David; Healy, David

2012-01-01

155

School-Turnaround Call Points Up Challenges  

ERIC Educational Resources Information Center

The U.S. secretary of education's call to "turn around" the nation's 5,000 worst-performing schools has found a warm welcome among educators and policymakers who see that focus as long overdue. But it has also sparked debate about how--and whether--such an enormous leadership and management challenge can be accomplished. Secretary of Education…

Gewertz, Catherine

2009-01-01

156

Hierarchical optimization of microcellular call handoffs  

Microsoft Academic Search

This paper presents a novel hierarchical optimization handoff algorithm (HOHA) which has superior performance over the conventional 1- and 2-threshold handoff algorithms. The proposed algorithm scans through layers of call handoff options and determines the best candidate based on a heuristic that synchronises reciprocal handoffs in adjacent cells and maximises the spare channel capacity in the destination cells. Computer simulation

B. L. Lim; W. C. Wong

1993-01-01

157

Hierarchical optimization of microcellular call handoffs  

Microsoft Academic Search

In this paper, we present a novel hierarchical optimization handoff algorithm (HOHA) which has superior performance over the conventional one- and two-threshold handoff algorithms. Our proposed algorithm scans through layers of call handoff options and determines the best candidate based on a heuristic that synchronizes reciprocal handoffs in adjacent cells and maximizes the spare channel capacity in the destination cells.

B. L. Lim; Lawrence W. C. Wong

1999-01-01

158

Call by Contract for Cryptographic Protocols.  

National Technical Information Service (NTIS)

A compositional approach to protocol design and analysis is recognized as advantageous. We wish to perform design decomposition in a way that permits independent design and verification of components, and preserves security and correctness goals when the ...

J. Millen J. Guttman J. Ramsdell J. Sheehy B. Sniffen

2006-01-01

159

Contextualized Approach to Language and Literacy (Project CALL): Capitalizing on Varied Activities and Contexts to Teach Early Literacy Skills  

ERIC Educational Resources Information Center

In a federally funded early literacy project, various instructional activities were embedded into an array of classroom contexts to provide supplemental literacy instruction and to contrast children's engagement and participation in different contexts and participant structures. The study was conducted with English- and Spanish-speaking children…

Culatta, Barbara; Hall, Kendra; Kovarsky, Dana; Theadore, Geraldine

2007-01-01

160

A micro-geography of fear: learning to eavesdrop on alarm calls of neighbouring heterospecifics.  

PubMed

Many vertebrates eavesdrop on alarm calls of other species, which is a remarkable ability, given geographical variation in community composition and call diversity within and among species. We used micro-geographical variation in community composition to test whether individuals recognize heterospecific alarm calls by: (i) responding to acoustic features shared among alarm calls; (ii) having innate responses to particular heterospecific calls; or (iii) learning specific alarm calls. We found that superb fairy-wrens (Malurus cyaneus) fled to cover to playback of noisy miner (Manorina melanocephala) aerial predator alarm calls only in locations where miners were present, suggesting that learning rather than acoustic structure determines response. Sites with and without miners were well within the dispersal distance of fairy-wrens, and philopatric males and dispersing females showed the same pattern, so that local genetic adaptation is extremely unlikely. Furthermore, where miners were present, fairy-wrens responded appropriately to different miner calls, implying eavesdropping on their signalling system rather than fleeing from miners themselves. Learned eavesdropping on alarm calls enables individuals to harvest ecologically relevant information from heterospecifics on an astonishingly fine spatial scale. Such phenotypic plasticity is valuable in a changing world, where individuals can be exposed to new species. PMID:21849313

Magrath, Robert D; Bennett, Thomas H

2012-03-01

161

A micro-geography of fear: learning to eavesdrop on alarm calls of neighbouring heterospecifics  

PubMed Central

Many vertebrates eavesdrop on alarm calls of other species, which is a remarkable ability, given geographical variation in community composition and call diversity within and among species. We used micro-geographical variation in community composition to test whether individuals recognize heterospecific alarm calls by: (i) responding to acoustic features shared among alarm calls; (ii) having innate responses to particular heterospecific calls; or (iii) learning specific alarm calls. We found that superb fairy-wrens (Malurus cyaneus) fled to cover to playback of noisy miner (Manorina melanocephala) aerial predator alarm calls only in locations where miners were present, suggesting that learning rather than acoustic structure determines response. Sites with and without miners were well within the dispersal distance of fairy-wrens, and philopatric males and dispersing females showed the same pattern, so that local genetic adaptation is extremely unlikely. Furthermore, where miners were present, fairy-wrens responded appropriately to different miner calls, implying eavesdropping on their signalling system rather than fleeing from miners themselves. Learned eavesdropping on alarm calls enables individuals to harvest ecologically relevant information from heterospecifics on an astonishingly fine spatial scale. Such phenotypic plasticity is valuable in a changing world, where individuals can be exposed to new species.

Magrath, Robert D.; Bennett, Thomas H.

2012-01-01

162

Comparing responses of four ungulate species to playbacks of baboon alarm calls.  

PubMed

A growing body of evidence suggests that a wide range of animals can recognize and respond appropriately to calls produced by other species. Social learning has been implicated as a possible mechanism by which heterospecific call recognition might develop. To examine whether familiarity and/or shared vulnerability with the calling species might influence the ability of sympatric species to distinguish heterospecific alarm calls, we tested whether four ungulate species (impala: Aepyceros melampus; tsessebe: Damaliscus lunatus; zebra: Equus burchelli; wildebeest: Connochaetes taurinus) could distinguish baboon (Papio hamadryas ursinus) alarm calls from other loud baboon calls produced during intra-specific aggressive interactions ('contest' calls). Overall, subjects' responses were stronger following playback of alarm calls than contest calls. Of the species tested, impala showed the strongest responses and the greatest difference in composite response scores, suggesting they were best able to differentiate call types. Compared with the other ungulate species, impala are the most frequent associates of baboons. Moreover, like baboons, they are susceptible to both lion and leopard attacks, whereas leopards rarely take the larger ungulates. Although it seems possible that high rates of association and/or shared vulnerability may influence impala's greater ability to distinguish among baboon call types, our results point to a stronger influence of familiarity. Ours is the first study to compare such abilities among several community members with variable natural histories, and we discuss future experiments that would more systematically examine development of these skills in young ungulates. PMID:20607576

Kitchen, Dawn M; Bergman, Thore J; Cheney, Dorothy L; Nicholson, James R; Seyfarth, Robert M

2010-11-01

163

47 CFR 80.225 - Requirements for selective calling equipment.  

Code of Federal Regulations, 2010 CFR

...for voluntary digital selective calling (DSC) equipment and selective calling equipment...Standards for Digital Selective Calling (DSC) Equipment Providing Minimum Distress and Safety...Class âDâ Digital Selective Calling (DSC)âMethods of testing...

2010-10-01

164

47 CFR 80.225 - Requirements for selective calling equipment.  

Code of Federal Regulations, 2010 CFR

...for voluntary digital selective calling (DSC) equipment and selective calling equipment...Standards for Digital Selective Calling (DSC) Equipment Providing Minimum Distress and Safety...Class âDâ Digital Selective Calling (DSC)âMethods of testing...

2009-10-01

165

Generalized theory of varying alpha  

NASA Astrophysics Data System (ADS)

In this paper, we formulate a generalization of the simple Bekenstein-Sandvik-Barrow-Magueijo theory of varying alpha by allowing the coupling constant ? for the corresponding scalar field ? to depend on ?. We focus on the situation where ? is exponential in ? and find the late-time behaviors that occur in matter-dominated and dark-energy dominated cosmologies. We also consider the situation when the background expansion scale factor of the Universe evolves in proportion to an arbitrary power of the cosmic time. We find the conditions under which the fine-structure “constant” increases with time, as in the Bekenstein-Sandvik-Barrow-Magueijo theory, and establish a cosmic no-hair behavior for accelerating universes. We also find the conditions under which the fine-structure constant can decrease with time and compare the whole family of models with astronomical data from quasar absorption spectra.

Barrow, John D.; Lip, Sean Z. W.

2012-01-01

166

Intra- and interspecific responses to Rafinesque’s big-eared bat (Corynorhinus rafinesquii) social calls.  

SciTech Connect

Bats respond to the calls of conspecifics as well as to calls of other species; however, few studies have attempted to quantify these responses or understand the functions of these calls. We tested the response of Rafinesque’s big-eared bats (Corynorhinus rafinesquii) to social calls as a possible method to increase capture success and to understand the function of social calls. We also tested if calls of bats within the range of the previously designated subspecies differed, if the responses of Rafinesque’s big-eared bats varied with geographic origin of the calls, and if other species responded to the calls of C. rafinesquii. We recorded calls of Rafinesque’s big-eared bats at two colony roost sites in South Carolina, USA. Calls were recorded while bats were in the roosts and as they exited. Playback sequences for each site were created by copying typical pulses into the playback file. Two mist nets were placed approximately 50–500 m from known roost sites; the net with the playback equipment served as the Experimental net and the one without the equipment served as the Control net. Call structures differed significantly between the Mountain and Coastal Plains populations with calls from the Mountains being of higher frequency and longer duration. Ten of 11 Rafinesque’s big-eared bats were caught in the Control nets and, 13 of 19 bats of other species were captured at Experimental nets even though overall bat activity did not differ significantly between Control and Experimental nets. Our results suggest that Rafinesque’s big-eared bats are not attracted to conspecifics’ calls and that these calls may act as an intraspecific spacing mechanism during foraging.

Loeb, Susan, C.; Britzke, Eric, R.

2010-07-01

167

House Calls and the ACGME Competencies  

Microsoft Academic Search

Background: The Accreditation Council for Graduate Medical Education (ACGME) “core competencies” (patient care, medical knowledge, interpersonal and communication skills, practice-based learning, and systems-based practice) are challenging to achieve in today's complex, high-acuity, hospital-based setting. House calls provide unique clinical exposure to opportunities for learning the ACGME competencies in a single integrated experience. We review the medical literature on the educational

Jennifer Hayashi; Colleen Christmas

2009-01-01

168

Designing a Call Center with Impatient Customers  

Microsoft Academic Search

The most common model to support workforce management of telephone call centers is the M\\/M\\/N\\/B model, in particular its special cases M\\/M\\/N (Erlang C, which models out busy signals) and M\\/M\\/N\\/N (Erlang B, disallowing waiting). All of these models lack a central prevalent feature, namely, that impatient customers might decide to leave (abandon) before their service begins. In this paper,

O. Garnet; A. Mandelbaum; M. Reiman

2002-01-01

169

Selective Call Out and Real Time Bidding  

Microsoft Academic Search

Ads on the Internet are increasingly sold via ad exchanges such as\\u000aRightMedia, AdECN and Doubleclick Ad Exchange. These exchanges allow real-time\\u000abidding, that is, each time the publisher contacts the exchange, the exchange\\u000a``calls out'' to solicit bids from ad networks. This aspect of soliciting bids\\u000aintroduces a novel aspect, in contrast to existing literature. This suggests\\u000adeveloping a

Tanmoy Chakraborty; Eyal Even-Dar; Sudipto Guha; Yishay Mansour; S. Muthukrishnan

2010-01-01

170

Anomaly Detection in Emergency Call Data The First Step to the Intelligent Emergency Call System Management  

Microsoft Academic Search

A collaborative Emergency call taking information system in the Czech Republic processes calls on the European 112 emergency number. Amounts of various incident records are stored in its databases. The data can be used for mining spatial and temporal anomalies. When such an anomalous situation is detected so that the system could suffer from local or temporal performance decrease, either

Petr Klement; V. Snasel

2009-01-01

171

Calling dynamics and call synchronization in a local group of unison bout callers.  

PubMed

In many species of chorusing frogs, callers can rapidly adjust their call timing with reference to neighboring callers so as to maintain call rate while minimizing acoustic interference. The rules governing the interactions, in particular, who is listening to whom are largely unknown, presumably influenced by distance between callers, caller density, and intensities of interfering calls. We report vocal interactions in a unison bout caller, the green tree frog (Hyla cinerea). Using a microphone array, we monitored bouts from a local group of six callers embedded in a larger chorus. Data were analyzed in a 21-min segment at the peak of the chorus. Callers within this group were localized and their voices were separated for analysis of spatio-temporal interactions. We show that callers in this group: (1) synchronize with one another, (2) prefer to time their calls antiphonally, almost exactly at one-third and two-thirds of the call intervals of their neighbors, (3) tolerate call collision when antiphonal calling is not possible, and (4) perform discrete phase-hopping between three preferred phases when tracking other callers. Further, call collision increases and phase-locking decreases, with increasing inter-caller spacing. We conclude that the precise phase-positioning, phase-tracking, and phase-hopping minimizes acoustic jamming while maintaining chorus synchrony. PMID:24249152

Jones, Douglas L; Jones, Russell L; Ratnam, Rama

2014-01-01

172

Call progress time measurement in IP telephony  

NASA Astrophysics Data System (ADS)

Usually a voice call is established through multiple stages in IP telephony. In the first stage, a phone number is dialed to reach a near-end or call-originating IP-telephony gateway. The next stages involve user identification through delivering an m-digit user-id to the authentication and/or billing server, and then user authentication by using an n- digit PIN. After that, the caller is allowed (last stage dial tone is provided) to dial a destination phone number provided that authentication is successful. In this paper, we present a very flexible method for measuring call progress time in IP telephony. The proposed technique can be used to measure the system response time at every stage. It is flexible, so that it can be easily modified to include new `tone' or a set of tones, or `voice begin' can be used in every stage to detect the system's response. The proposed method has been implemented using scripts written in Hammer visual basic language for testing with a few commercially available IP telephony gateways.

Khasnabish, Bhumip

1999-11-01

173

Adoption activities on the Internet: a call for regulation.  

PubMed

There is a growing practice of adoption services on the Internet with varying degrees of regulation, depending on whether it is domestic infant adoption, public foster care adoption, or international adoption. Regulation is particularly lacking in domestic infant adoptions, with Web sites connecting prospective birth and adoptive parents, sometimes through an adoption brokerage service. International adoptions can also be plagued by unethical practices as the Internet has become available in both developed and developing countries. These activities, although offering the benefits of privacy and convenience, also pose serious problems of potential fraud, exploitation, and, most important, lack of professional consideration of the child's best interest. In this article, the authors review the landscape of current Internet-based adoption activities, examine the benefits and risks of Internet-based adoption activities, and call for social work self-regulation and leadership. PMID:20632655

Roby, Jini L; White, Holly

2010-07-01

174

Adult Vampire Bats Produce Contact Calls When Isolated: Acoustic Variation by Species, Population, Colony, and Individual  

PubMed Central

Background Bat pups produce individually distinct isolation calls to facilitate maternal recognition. Increasing evidence suggests that, in group-living bat species, adults often use similar calls to maintain contact. We investigated if isolated adults from all three species of the highly cooperative vampire bats (Phyllostomidae: Desmodontinae) would produce vocally distinct contact calls when physically isolated. Methods/Principal Findings We assessed variation in contact calls recorded from isolated captive and wild-caught adult common vampire bats (Desmodus rotundus), white-winged vampire bats (Diaemus youngi) and hairy-legged vampire bats (Diphylla ecaudata). We compared species-typical contact call structure, and used information theory and permuted discriminate function analyses to examine call structure variation, and to determine if the individuality of contact calls is encoded by different call features across species and populations. We found that isolated adult vampire bats produce contact calls that vary by species, population, colony, and individual. However, much variation occurred within a single context and individual. We estimated signature information for captive Diaemus (same colony), captive Desmodus (same colony), and wild Desmodus (different colonies) at 3.21, 3.26, and 3.88 bits, respectively. Contact calls from a captive colony of Desmodus were less individually distinct than calls from wild-caught Desmodus from different colonies. Both the degree of individuality and parameters encoding individuality differed between the bats from a single captive colony and the wild-caught individuals from different groups. This result is consistent with, but not sufficient evidence of, vocal convergence in groups. Conclusion Our results show that adult vampire bats of all three species produce highly variable contact calls when isolated. Contact calls contain sufficient information for vocal discrimination, but also possess more intra-individual variation than is required for the sole purpose of identifying individuals.

Carter, Gerald G.; Logsdon, Ryane; Arnold, Bryan D.; Menchaca, Angelica; Medellin, Rodrigo A.

2012-01-01

175

Calling patterns in human communication dynamics  

PubMed Central

Modern technologies not only provide a variety of communication modes (e.g., texting, cell phone conversation, and online instant messaging), but also detailed electronic traces of these communications between individuals. These electronic traces indicate that the interactions occur in temporal bursts. Here, we study intercall duration of communications of the 100,000 most active cell phone users of a Chinese mobile phone operator. We confirm that the intercall durations follow a power-law distribution with an exponential cutoff at the population level but find differences when focusing on individual users. We apply statistical tests at the individual level and find that the intercall durations follow a power-law distribution for only 3,460 individuals (3.46%). The intercall durations for the majority (73.34%) follow a Weibull distribution. We quantify individual users using three measures: out-degree, percentage of outgoing calls, and communication diversity. We find that the cell phone users with a power-law duration distribution fall into three anomalous clusters: robot-based callers, telecom fraud, and telephone sales. This information is of interest to both academics and practitioners, mobile telecom operators in particular. In contrast, the individual users with a Weibull duration distribution form the fourth cluster of ordinary cell phone users. We also discover more information about the calling patterns of these four clusters (e.g., the probability that a user will call the cr-th most contact and the probability distribution of burst sizes). Our findings may enable a more detailed analysis of the huge body of data contained in the logs of massive users.

Jiang, Zhi-Qiang; Xie, Wen-Jie; Li, Ming-Xia; Podobnik, Boris; Zhou, Wei-Xing; Stanley, H. Eugene

2013-01-01

176

In Brief: Geosciences call to action  

NASA Astrophysics Data System (ADS)

The U.S. National Science Foundation's (NSF) Advisory Committee for Geosciences has issued a call to action to the geosciences community. “Over the next decade, the geosciences community commits to developing a framework to understand and predict responses of the Earth as a system—from the space-atmosphere boundary to the core, including the influences of humans and ecosystems,” states a report, “GEO Vision: Unraveling Earth's Complexities Through the Geosciences,” issued by the committee on 15 October. The report presents three major challenges: understanding and forecasting the behavior of a complex and evolving Earth system, reducing vulnerability and sustaining life, and growing the geosciences workforce of the future.

Showstack, Randy

2009-10-01

177

Mobbing calls signal predator category in a kin group-living bird species.  

PubMed

Many prey species gather together to approach and harass their predators despite the associated risks. While mobbing, prey usually utter calls and previous experiments have demonstrated that mobbing calls can convey information about risk to conspecifics. However, the risk posed by predators also differs between predator categories. The ability to communicate predator category would be adaptive because it would allow other mobbers to adjust their risk taking. I tested this idea in Siberian jays Perisoreus infaustus, a group-living bird species, by exposing jay groups to mounts of three hawk and three owl species of varying risks. Groups immediately approached to mob the mount and uttered up to 14 different call types. Jays gave more calls when mobbing a more dangerous predator and when in the presence of kin. Five call types were predator-category-specific and jays uttered two hawk-specific and three owl-specific call types. Thus, this is one of the first studies to demonstrate that mobbing calls can simultaneously encode information about both predator category and the risk posed by a predator. Since antipredator calls of Siberian jays are known to specifically aim at reducing the risk to relatives, kin-based sociality could be an important factor in facilitating the evolution of predator-category-specific mobbing calls. PMID:19474047

Griesser, Michael

2009-08-22

178

Probabilistic base calling of Solexa sequencing data  

PubMed Central

Background Solexa/Illumina short-read ultra-high throughput DNA sequencing technology produces millions of short tags (up to 36 bases) by parallel sequencing-by-synthesis of DNA colonies. The processing and statistical analysis of such high-throughput data poses new challenges; currently a fair proportion of the tags are routinely discarded due to an inability to match them to a reference sequence, thereby reducing the effective throughput of the technology. Results We propose a novel base calling algorithm using model-based clustering and probability theory to identify ambiguous bases and code them with IUPAC symbols. We also select optimal sub-tags using a score based on information content to remove uncertain bases towards the ends of the reads. Conclusion We show that the method improves genome coverage and number of usable tags as compared with Solexa's data processing pipeline by an average of 15%. An R package is provided which allows fast and accurate base calling of Solexa's fluorescence intensity files and the production of informative diagnostic plots.

Rougemont, Jacques; Amzallag, Arnaud; Iseli, Christian; Farinelli, Laurent; Xenarios, Ioannis; Naef, Felix

2008-01-01

179

Apoptosis: Calling Time on Apoptosome Activity  

NSDL National Science Digital Library

Apoptosis is a controlled form of cellular demolition, catalyzed by a family of cysteine proteases called caspases. In response to diverse proapoptotic stimuli, caspase-9 is recruited and activated within an oligomeric complex called the apoptosome. The apoptosome drives autocatalytic processing of caspase-9, triggering a proteolytic caspase cascade that results in the biochemical and morphological changes characteristic of cell death. It is unclear why caspase-9 undergoes autocatalytic processing following apoptosome recruitment, because interdomain processing is dispensable for caspase-9 activity. A study has shed light on this issue by demonstrating that caspase-9 processing within the apoptosome promotes its displacement from the complex, leading to inactivation of this protease. Thus, autoprocessing of caspase-9 within the apoptosome serves as a “molecular timer” that limits the proteolytic activity of this complex through displacement of bound caspase-9 molecules. This timer mechanism may enable cells to prevent low amounts of apoptosome activation from spiraling out of control unless sufficient numbers of apoptosomes are assembled within a particular time window, which would drive full-blown caspase activation and apoptosis.

Colin Adrain (Cambridge;Medical Research Council Laboratory of Molecular Biology REV); Seamus J. Martin (Ireland.;Trinity College REV)

2009-10-06

180

Time varying networks and the weakness of strong ties  

PubMed Central

In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the temporal evolution of users' egocentric networks. We encode this observation in a reinforcement process defining a time-varying network model that exhibits the emergence of strong and weak ties. We study the effect of time-varying and heterogeneous interactions on the classic rumour spreading model in both synthetic, and real-world networks. We observe that strong ties severely inhibit information diffusion by confining the spreading process among agents with recurrent communication patterns. This provides the counterintuitive evidence that strong ties may have a negative role in the spreading of information across networks.

Karsai, Marton; Perra, Nicola; Vespignani, Alessandro

2014-01-01

181

Time varying networks and the weakness of strong ties.  

PubMed

In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the temporal evolution of users' egocentric networks. We encode this observation in a reinforcement process defining a time-varying network model that exhibits the emergence of strong and weak ties. We study the effect of time-varying and heterogeneous interactions on the classic rumour spreading model in both synthetic, and real-world networks. We observe that strong ties severely inhibit information diffusion by confining the spreading process among agents with recurrent communication patterns. This provides the counterintuitive evidence that strong ties may have a negative role in the spreading of information across networks. PMID:24510159

Karsai, Márton; Perra, Nicola; Vespignani, Alessandro

2014-01-01

182

OnlineCall: fast online parameter estimation and base calling for illumina's next-generation sequencing  

PubMed Central

Motivation: Next-generation DNA sequencing platforms are becoming increasingly cost-effective and capable of providing enormous number of reads in a relatively short time. However, their accuracy and read lengths are still lagging behind those of conventional Sanger sequencing method. Performance of next-generation sequencing platforms is fundamentally limited by various imperfections in the sequencing-by-synthesis and signal acquisition processes. This drives the search for accurate, scalable and computationally tractable base calling algorithms capable of accounting for such imperfections. Results: Relying on a statistical model of the sequencing-by-synthesis process and signal acquisition procedure, we develop a computationally efficient base calling method for Illumina's sequencing technology (specifically, Genome Analyzer II platform). Parameters of the model are estimated via a fast unsupervised online learning scheme, which uses the generalized expectation–maximization algorithm and requires only 3 s of running time per tile (on an Intel i7 machine @3.07GHz, single core)—a three orders of magnitude speed-up over existing parametric model-based methods. To minimize the latency between the end of the sequencing run and the generation of the base calling reports, we develop a fast online scalable decoding algorithm, which requires only 9 s/tile and achieves significantly lower error rates than the Illumina's base calling software. Moreover, it is demonstrated that the proposed online parameter estimation scheme efficiently computes tile-dependent parameters, which can thereafter be provided to the base calling algorithm, resulting in significant improvements over previously developed base calling methods for the considered platform in terms of performance, time/complexity and latency. Availability: A C code implementation of our algorithm can be downloaded from http://www.cerc.utexas.edu/OnlineCall/ Contact: hvikalo@ece.utexas.edu Supplementary information: Supplementary data are available at Bioinformatics online.

Das, Shreepriya; Vikalo, Haris

2012-01-01

183

Testing Composites  

NASA Technical Reports Server (NTRS)

A device for testing composites for strength characteristics has been developed by Acoustic Emission Technology Corporation. Called the Model 206AU, the system is lightweight and portable. It is comprised of three sections. The "pulser" section injects ultrasonic waves into the material under test. A receiver picks up the simulated stress waves as they pass through the material and relays the signals to the acoustic emission section, where they are electronically analyzed.

1981-01-01

184

Call Admission Control Approaches in Beyond 3G Networks Using Multi Criteria Decision Making  

Microsoft Academic Search

The next generation wireless networks (NGWN) should cater the varied requirements of the user and applications. The call admission control (CAC) is one of the radio resource management (RRM) technique used in the wireless networks. Unlike the CAC in homogeneous wireless networks the CAC in next generation wireless networks is very complex. In the next generation heterogeneous wireless networks, a

H. S. R. Babu; G. Shankar; P. S. Satyanarayana

2009-01-01

185

From nestling calls to fledgling silence: adaptive timing of change in response to aerial alarm calls  

PubMed Central

Young birds and mammals are extremely vulnerable to predators and so should benefit from responding to parental alarm calls warning of danger. However, young often respond differently from adults. This difference may reflect: (i) an imperfect stage in the gradual development of adult behaviour or (ii) an adaptation to different vulnerability. Altricial birds provide an excellent model to test for adaptive changes with age in response to alarm calls, because fledglings are vulnerable to a different range of predators than nestlings. For example, a flying hawk is irrelevant to a nestling in a enclosed nest, but is dangerous to that individual once it has left the nest, so we predict that young develop a response to aerial alarm calls to coincide with fledging. Supporting our prediction, recently fledged white-browed scrubwrens, Sericornis frontalis, fell silent immediately after playback of their parents' aerial alarm call, whereas nestlings continued to calling despite hearing the playback. Young scrubwrens are therefore exquisitely adapted to the changing risks faced during development.

Magrath, Robert D; Platzen, Dirk; Kondo, Junko

2006-01-01

186

Call Admission Control in OFDM Wireless Multimedia Networks  

Microsoft Academic Search

Call admission control is an effective mechanism to guarantee robust services in wireless networks. In this paper, we present several call admission control algorithms and queueing models for the subcarrier allocation in the OFDM-based wireless multimedia networks. Call connection requests are differentiated into narrow-band call and wide-band call. For either class of calls, the traffic process is characterized as batch

Yan Zhang

2008-01-01

187

Call recognition in the bullfrog, Rana catesbeiana: Generalization along the duration continuum  

NASA Astrophysics Data System (ADS)

Male bullfrogs emit multicroak, quasiharmonic advertisement calls that function in mate attraction and neighbor recognition. The degree of variability of acoustic features in these calls can influence perceptual decisions by conspecific receivers. Analysis of duration of individual croaks in spontaneous advertisement calls of a sample of males shows considerable intraindividual variability in this feature, even within short chorusing bouts. The influence of this intraindividual variability on behavior was examined in a series of evoked calling experiments. When presented with synthetic calls whose croak durations varied over the range of the natural variability in this feature, males responded similarly to intermediate and long duration croaks, but significantly less to short duration croaks. When presented with playbacks of calls with croak durations outside the natural range of variability, males again responded significantly less to shorter durations. The response gradient for duration is thus asymmetrical, with stimuli at the shorter end of the continuum evoking fewer responses than stimuli at the longer end. This asymmetry may be related to the biological demands of rejecting perception of heterospecific advertisement calls, and of mediating appropriate responses to conspecific aggressive calls. The shape of the response gradient for duration may reflect a process of stimulus generalization.

Simmons, Andrea Megela

2004-03-01

188

Sharing programming resources between Bio* projects through remote procedure call and native call stack strategies.  

PubMed

Open-source software (OSS) encourages computer programmers to reuse software components written by others. In evolutionary bioinformatics, OSS comes in a broad range of programming languages, including C/C++, Perl, Python, Ruby, Java, and R. To avoid writing the same functionality multiple times for different languages, it is possible to share components by bridging computer languages and Bio* projects, such as BioPerl, Biopython, BioRuby, BioJava, and R/Bioconductor. In this chapter, we compare the two principal approaches for sharing software between different programming languages: either by remote procedure call (RPC) or by sharing a local call stack. RPC provides a language-independent protocol over a network interface; examples are RSOAP and Rserve. The local call stack provides a between-language mapping not over the network interface, but directly in computer memory; examples are R bindings, RPy, and languages sharing the Java Virtual Machine stack. This functionality provides strategies for sharing of software between Bio* projects, which can be exploited more often. Here, we present cross-language examples for sequence translation, and measure throughput of the different options. We compare calling into R through native R, RSOAP, Rserve, and RPy interfaces, with the performance of native BioPerl, Biopython, BioJava, and BioRuby implementations, and with call stack bindings to BioJava and the European Molecular Biology Open Software Suite. In general, call stack approaches outperform native Bio* implementations and these, in turn, outperform RPC-based approaches. To test and compare strategies, we provide a downloadable BioNode image with all examples, tools, and libraries included. The BioNode image can be run on VirtualBox-supported operating systems, including Windows, OSX, and Linux. PMID:22399473

Prins, Pjotr; Goto, Naohisa; Yates, Andrew; Gautier, Laurent; Willis, Scooter; Fields, Christopher; Katayama, Toshiaki

2012-01-01

189

Calibrating passive acoustic monitoring: correcting humpback whale call detections for site-specific and time-dependent environmental characteristics.  

PubMed

This paper demonstrates the importance of accounting for environmental effects on passive underwater acoustic monitoring results. The situation considered is the reduction in shipping off the California coast between 2008-2010 due to the recession and environmental legislation. The resulting variations in ocean noise change the probability of detecting marine mammal vocalizations. An acoustic model was used to calculate the time-varying probability of detecting humpback whale vocalizations under best-guess environmental conditions and varying noise. The uncorrected call counts suggest a diel pattern and an increase in calling over a two-year period; the corrected call counts show minimal evidence of these features. PMID:24181982

Helble, Tyler A; D'Spain, Gerald L; Campbell, Greg S; Hildebrand, John A

2013-11-01

190

Pathological aspects of so called "hilar cholangiocarcinoma".  

PubMed

Cholangiocarcinoma (CC) arising from the large intrahepatic bile ducts and extrahepatic hilar bile ducts share clinicopathological features and have been called hilar and perihilar CC as a group. However, "hilar and perihilar CC" are also used to refer exclusively to the intrahepatic hilar type CC or, more commonly, the extrahepatic hilar CC. Grossly, a major distinction can be made between papillary and non-papillary tumors. Histologically, most hilar CCs are well to moderately differentiated conventional type (biliary) carcinomas. Immunohistochemically, CK7, CK20, CEA and MUC1 are normally expressed, being MUC2 positive in less than 50% of cases. Two main premalignant lesions are known: biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the biliary tract (IPNB). IPNB includes the lesions previously named biliary papillomatosis and papillary carcinoma. A series of 29 resected hilar CC from our archives is reviewed. Most (82.8%) were conventional type adenocarcinomas, mostly well to moderately differentiated, although with a broad morphological spectrum; three cases exhibited a poorly differentiated cell component resembling signet ring cells. IPNB was observed in 5 (17.2%), four of them with an associated invasive carcinoma. A clear cell type carcinoma, an adenosquamous carcinoma and two gastric foveolar type carcinomas were observed. PMID:23919110

Castellano-Megías, Víctor M; Ibarrola-de Andrés, Carolina; Colina-Ruizdelgado, Francisco

2013-07-15

191

Pathological aspects of so called "hilar cholangiocarcinoma"  

PubMed Central

Cholangiocarcinoma (CC) arising from the large intrahepatic bile ducts and extrahepatic hilar bile ducts share clinicopathological features and have been called hilar and perihilar CC as a group. However, “hilar and perihilar CC” are also used to refer exclusively to the intrahepatic hilar type CC or, more commonly, the extrahepatic hilar CC. Grossly, a major distinction can be made between papillary and non-papillary tumors. Histologically, most hilar CCs are well to moderately differentiated conventional type (biliary) carcinomas. Immunohistochemically, CK7, CK20, CEA and MUC1 are normally expressed, being MUC2 positive in less than 50% of cases. Two main premalignant lesions are known: biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the biliary tract (IPNB). IPNB includes the lesions previously named biliary papillomatosis and papillary carcinoma. A series of 29 resected hilar CC from our archives is reviewed. Most (82.8%) were conventional type adenocarcinomas, mostly well to moderately differentiated, although with a broad morphological spectrum; three cases exhibited a poorly differentiated cell component resembling signet ring cells. IPNB was observed in 5 (17.2%), four of them with an associated invasive carcinoma. A clear cell type carcinoma, an adenosquamous carcinoma and two gastric foveolar type carcinomas were observed.

Castellano-Megias, Victor M; Ibarrola-de Andres, Carolina; Colina-Ruizdelgado, Francisco

2013-01-01

192

Calling under pressure: short-finned pilot whales make social calls during deep foraging dives  

PubMed Central

Toothed whales rely on sound to echolocate prey and communicate with conspecifics, but little is known about how extreme pressure affects pneumatic sound production in deep-diving species with a limited air supply. The short-finned pilot whale (Globicephala macrorhynchus) is a highly social species among the deep-diving toothed whales, in which individuals socialize at the surface but leave their social group in pursuit of prey at depths of up to 1000 m. To investigate if these animals communicate acoustically at depth and test whether hydrostatic pressure affects communication signals, acoustic DTAGs logging sound, depth and orientation were attached to 12 pilot whales. Tagged whales produced tonal calls during deep foraging dives at depths of up to 800 m. Mean call output and duration decreased with depth despite the increased distance to conspecifics at the surface. This shows that the energy content of calls is lower at depths where lungs are collapsed and where the air volume available for sound generation is limited by ambient pressure. Frequency content was unaffected, providing a possible cue for group or species identification of diving whales. Social calls may be important to maintain social ties for foraging animals, but may be impacted adversely by vessel noise.

Jensen, Frants H.; Perez, Jacobo Marrero; Johnson, Mark; Soto, Natacha Aguilar; Madsen, Peter T.

2011-01-01

193

Introducing psychometrical validation of questionnaires in CALL research: the case of measuring attitude towards CALL  

Microsoft Academic Search

The great majority of questionnaires measuring non-observable constructs such as attitude towards CALL are often developed from a specific point of view and are seldom followed by psychometrical validation. Psychometrical properties of the questionnaire, such as construct validity and reliability, then remain unanswered too often, laying a heavy burden upon the generalizability of the obtained results. In light of recent

M. Vandewaetere; P. Desmet

2009-01-01

194

Jackup placement calls for extreme care  

SciTech Connect

Jackup drilling rigs are exceedingly useful tools for exploration. The integrity of the jackup rig is very dependent on the specific location at which the unit is operating. Therefore, an accurate assessment of the environment for the location is essential. For safe operations, independent assessments should be made to establish the safety of the rig for specific sites and environments. While it is the task of the designer and the builder to produce a jackup which is suitable for the rigors of operation, it is the responsibility of the owner to operate the unit within an acceptable level of risk. When owners rely upon marine surveyors, with the aid of their organizations' criteria, to decide the safety of a jackup on a location, they should be acutely aware of the criteria and assumptions in which they are placing their faith. When a drilling contractor instructs his marine surveyor to assess the suitability of a rig for a location by performing a site-specific analysis, the assumptions made in the calculations can make the results vary widely.

Sharples, B.P.M.; Gorman, M.T.; Firstenberg, C.E.

1986-05-01

195

Buckling response of laminates with spatially varying fiber orientations  

NASA Technical Reports Server (NTRS)

The buckling response of a symmetrically laminated composite panel with a spatially varying fiber orientation has been analyzed. Variation of the fiber orientation angle as a function of the position in the panel results in a composite laminate with stiffness properties that are functions of the panel coordinates. The laminates are therefore termed variable stiffness panels. The fiber orientation is assumed to vary only in one spatial direction, although the analysis can be extended to fiber orientations that vary in two spatial directions. The Ritz Method has been used to find the buckling loads and buckling modes for the variable stiffness panels for two different cases. In one of the cases the fiber orientation is assumed to change in the direction of the applied load. The other case is the one in which the fiber orientation varies in a direction perpendicular to the loading direction. Improvements in the buckling load of up to 80 percent over straight fiber configurations were found. Results for three different panel aspect ratios are presented.

Olmedo, Reynaldo; Gurdal, Zafer

1993-01-01

196

Workload characterization using lightweight system call tracing and reexecution  

Microsoft Academic Search

This paper shows how system call traces can be obtained with minimal interference to the system being characterized, and used as realistic, repeatable workloads for experiments to evaluate operating system and file system designs and configuration alternatives. Our system call trace mechanism, called ULTra, captures a complete trace of each UNIX process's calls to the operating system. The performance impact

Ariel N. Burton; Paul H. J. Kelly

1998-01-01

197

Tracing and reexecuting operating system calls for reproducible performance experiments  

Microsoft Academic Search

This paper shows how system call traces can be obtained with minimal interference to the system being characterized, and used as realistic, repeatable workloads for experiments to evaluate operating system and file system designs and configuration alternatives. Our system call trace mechanism, called ULTra, captures a complete trace of each UNIX process’s calls to the operating system. The performance impact

Ariel N Burton; Paul H. J Kelly

2000-01-01

198

Integration of pricing with call admission control for wireless networks  

Microsoft Academic Search

Traditional call admission control (CAC) schemes that mainly focus on the trade off between new call blocking probability and handoff call blocking probability can not solve the problem of congestion in wireless networks. We investigate the role of pricing as an additional dimension of the call admission control process in order to efficiently and effectively control the use of wireless

Jiongkuan Hou; Jie Yang; Symeon Papavassiliou

2001-01-01

199

Fairness optimization of thinning Call Admission Control in wireless networks  

Microsoft Academic Search

Resource reservation call admission control (CAC) schemes constitute an efficient solution for prioritizing high priority calls. Issues concerning fairness among calls arise during the implementation of CAC. In this paper, a new optimization model selecting the admission probability in thinning schemes is proposed to provide fairness in resource sharing among different input call stream flows. The existence of an optimal

Georgios I. Tsiropoulos; Dimitrios G. Stratogiannis; John D. Kanellopoulos; Panayotis G. Cottis

2009-01-01

200

Optimal Call Admission Control Policy In Wireless Networks  

Microsoft Academic Search

It is well known that the call admission policy has a big impact on the performance of a wireless network. Due to the nonlinear dependence between new calls and handoff calls, it becomes quite difficult to exactly model a wireless network. In this paper, we take all the incoming calls to a single cell of a wireless network as one

Wenlong Ni; Wei Li; Mansoor Alam

2008-01-01

201

Insensitive Call Admission Control for Wireless Multiservice Networks  

Microsoft Academic Search

WO important quality of service measures for wireless networks are the fraction of new and handover calls that are blocked due to the lack of enough free resources. As handover blocking is more annoying than new call blocking for subscribers, efficient call admission control (CAC) strategies can be used to reject new calls in order to reserve resources for future

Jorge Martinez-Bauset; Vicent Pla; Elena Bernal-Mor

2011-01-01

202

Linking Calling Orientations to Organizational Attachment via Organizational Instrumentality  

ERIC Educational Resources Information Center

Despite an emerging interest in callings, researchers know little about whether calling orientations matter in the workplace. We explore the under-examined relationship between a calling orientation and employees' attachment to their organizations. Although some theory suggests that callings may be negatively related to organizational attachment,…

Cardador, M. Teresa; Dane, Erik; Pratt, Michael G.

2011-01-01

203

Neural correlates of threat perception: neural equivalence of conspecific and heterospecific mobbing calls is learned.  

PubMed

Songbird auditory areas (i.e., CMM and NCM) are preferentially activated to playback of conspecific vocalizations relative to heterospecific and arbitrary noise. Here, we asked if the neural response to auditory stimulation is not simply preferential for conspecific vocalizations but also for the information conveyed by the vocalization. Black-capped chickadees use their chick-a-dee mobbing call to recruit conspecifics and other avian species to mob perched predators. Mobbing calls produced in response to smaller, higher-threat predators contain more "D" notes compared to those produced in response to larger, lower-threat predators and thus convey the degree of threat of predators. We specifically asked whether the neural response varies with the degree of threat conveyed by the mobbing calls of chickadees and whether the neural response is the same for actual predator calls that correspond to the degree of threat of the chickadee mobbing calls. Our results demonstrate that, as degree of threat increases in conspecific chickadee mobbing calls, there is a corresponding increase in immediate early gene (IEG) expression in telencephalic auditory areas. We also demonstrate that as the degree of threat increases for the heterospecific predator, there is a corresponding increase in IEG expression in the auditory areas. Furthermore, there was no significant difference in the amount IEG expression between conspecific mobbing calls or heterospecific predator calls that were the same degree of threat. In a second experiment, using hand-reared chickadees without predator experience, we found more IEG expression in response to mobbing calls than corresponding predator calls, indicating that degree of threat is learned. Our results demonstrate that degree of threat corresponds to neural activity in the auditory areas and that threat can be conveyed by different species signals and that these signals must be learned. PMID:21909363

Avey, Marc T; Hoeschele, Marisa; Moscicki, Michele K; Bloomfield, Laurie L; Sturdy, Christopher B

2011-01-01

204

Call for Papers: Photonics in Switching  

NASA Astrophysics Data System (ADS)

Call for Papers: Photonics in Switching

Guest Editors:

Lena Wosinska, Royal Institute of Technology (KTH) / ICT Sweden Madeleine Glick, Intel Research, Cambridge, UK

Technologies based on DWDM systems allow data transmission with bit rates of Tbit/s on a single fiber. To facilitate this enormous transmission volume, high-capacity and high-speed network nodes become inevitable in the optical network. Wideband switching, WDM switching, optical burst switching (OBS), and optical packet switching (OPS) are promising technologies for harnessing the bandwidth of WDM optical fiber networks in a highly flexible and efficient manner. As a number of key optical component technologies approach maturity, photonics in switching is becoming an increasingly attractive and practical solution for the next-generation of optical networks. The scope of this special issue is focused on the technology and architecture of optical switching nodes, including the architectural and algorithmic aspects of high-speed optical networks.

Scope of Submission

The scope of the papers includes, but is not limited to, the following topics:
  • WDM node architectures
  • Novel device technologies enabling photonics in switching, such as optical switch fabrics, optical memory, and wavelength conversion
  • Routing protocols
  • WDM switching and routing
  • Quality of service
  • Performance measurement and evaluation
  • Next-generation optical networks: architecture, signaling, and control
  • Traffic measurement and field trials
  • Optical burst and packet switching
  • OBS/OPS node architectures
  • Burst/Packet scheduling and routing algorithms
  • Contention resolution/avoidance strategies
  • Services and applications for OBS/OPS (e.g., grid networks, storage-area networks, etc.)
  • Burst assembly and ingress traffic shaping
  • Hybrid OBS/TDM or OBS/wavelength routing

Manuscript Submission

To submit to this special issue, follow the normal procedure for submission to JON and select ``Photonics in Switching' in the features indicator of the online submission form. For all other questions relating to this feature issue, please send an e-mail to jon@osa.org, subject line ``Photonics in Switching.' Additional information can be found on the JON website: http://www.osa-jon.org/journal/jon/author.cfm. Submission Deadline: 15 September 2006

Wosinska, Lena; Glick, Madeleine

2006-04-01

205

Composite Fasteners  

NASA Technical Reports Server (NTRS)

Flexible composite fasteners made of polyvinyl chloride or other resilient synthetic material designed for joining together various materials which may vary slightly in thickness during use. Fasteners easily installed and removed by hand and maintain approximately same tension in bonding materials together, regardless of subsequent movements of materials. Design and choice of material of new fasteners enables variety of uses, as book binders, hole sealers, insulating fasteners for electronic circuitry, or break-away energy-absorbing fasteners for vehicles in crashes.

Ng, G. S.

1986-01-01

206

Multi-component separation and analysis of bat echolocation calls.  

PubMed

The vast majority of animal vocalizations contain multiple frequency modulated (FM) components with varying amounts of non-linear modulation and harmonic instability. This is especially true of biosonar sounds where precise time-frequency templates are essential for neural information processing of echoes. Understanding the dynamic waveform design by bats and other echolocating animals may help to improve the efficacy of man-made sonar through biomimetic design. Bats are known to adapt their call structure based on the echolocation task, proximity to nearby objects, and density of acoustic clutter. To interpret the significance of these changes, a method was developed for component separation and analysis of biosonar waveforms. Techniques for imaging in the time-frequency plane are typically limited due to the uncertainty principle and interference cross terms. This problem is addressed by extending the use of the fractional Fourier transform to isolate each non-linear component for separate analysis. Once separated, empirical mode decomposition can be used to further examine each component. The Hilbert transform may then successfully extract detailed time-frequency information from each isolated component. This multi-component analysis method is applied to the sonar signals of four species of bats recorded in-flight by radiotelemetry along with a comparison of other common time-frequency representations. PMID:23297925

DiCecco, John; Gaudette, Jason E; Simmons, James A

2013-01-01

207

Hydride compositions  

DOEpatents

Disclosed are a composition for use in storing hydrogen and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the H equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to H, and then heating below the softening temperature of any of the constituents. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P{sub H}{sub 2} and determining H/M from the isothermic function of the composition.

Lee, Myung, W.

1994-01-01

208

The So-Called 'Face on Mars'  

NASA Technical Reports Server (NTRS)

(Released 13 April 2002) The Science The so called 'Face on Mars' can be seen slightly above center and to the right in this THEMIS visible image. This 3-km long knob, located near 10o N, 40o W (320o E), was first imaged by the Viking spacecraft in the 1970's and was seen by some to resemble a face carved into the rocks of Mars. Since that time the Mars Orbiter Camera on the Mars Global Surveyor spacecraft has provided detailed views of this hill that clearly show that it is a normal geologic feature with slopes and ridges carved by eons of wind and downslope motion due to gravity. A similar-size hill in Phoenix, Arizona resembles a camel lying on the ground, and Phoenicians whimsically refer to it as Camelback Mountain. Like the hills and knobs of Mars, however, Camelback Mountain was carved into its unusual shape by thousands of years of erosion. The THEMIS image provides a broad perspective of the landscape in this region, showing numerous knobs and hills that have been eroded into a remarkable array of different shapes. Many of these knobs, including the 'Face', have several flat ledges partway up the hill slopes. These ledges are made of more resistant layers of rock and are the last remnants of layers that once were continuous across this entire region. Erosion has completely removed these layers in most places, leaving behind only the small isolated hills and knobs seen today. Many of the hills and ridges in this area also show unusual deposits of material that occur preferentially on the cold, north-facing slopes. It has been suggested that these deposits were 'pasted' on the slopes, with the distinct, rounded boundary on their upslope edges being the highest remaining point of this pasted-on layer. In several locations, such as in the large knob directly south of the 'Face', these deposits occur at several different heights on the hill. This observation suggests the layer once draped the entire knob and has since been removed from all but the north-facing slopes. The presence of water ice in these layers is a likely possibility to account for their preservation only on the colder surfaces. Alternatively, these unique features could be the result of the slow downslope motion of the surface layer, possibly enhanced by the presence of ground ice. One argument against downslope motion is the observation that the uppermost rounded boundary of these layers typically occurs at approximately the same distance below the ridge crest. This would suggest the (seemingly) unlikely possibility that all of these layers had moved downslope the same amount regardless of where they are located. In either case, ground ice likely plays an important role in the formation and preservation of these deposits because they only occur on the cold slopes facing away from the Sun where ground ice is more stable and may still be present today. The Story Nature is an imaginative artist, creating all kinds of wonderful landforms, cloud shapes, and other patterned features that remind people of familiar things in our lives. We see a 'man in the moon' when it is full in the night sky, and dream of a dromedary-dotted desert when coming upon Arizona's Camelback Mountain or Colorado's 'Kissing Camels' in the 'Garden of the Gods.' Near Ludlow, California, a lonely prospector once noticed that the appealing outline of the mountains resembled a reclining woman, and named the place Sleeping Beauty. And this naming delight isn't limited to Earth. The Mars Pathfinder mission team couldn't help but name the rocks at the landing site, including a bear-headed-looking one named Yogi. Part of the fun of exploration is not just visiting a strange world, but relating to it in human terms. On Mars, we've already seen a valentine heart-shaped crater, a happy-faced crater, and even a murky and mysterious 'face' on Mars. This face (seen here about halfway down the image and to the right) is really just a hill with slopes and ridges that are shadowed in a way that can sometimes resemble a face from far away. The first picture of

2002-01-01

209

KRLMM: an adaptive genotype calling method for common and low frequency variants  

PubMed Central

Background SNP genotyping microarrays have revolutionized the study of complex disease. The current range of commercially available genotyping products contain extensive catalogues of low frequency and rare variants. Existing SNP calling algorithms have difficulty dealing with these low frequency variants, as the underlying models rely on each genotype having a reasonable number of observations to ensure accurate clustering. Results Here we develop KRLMM, a new method for converting raw intensities into genotype calls that aims to overcome this issue. Our method is unique in that it applies careful between sample normalization and allows a variable number of clusters k (1, 2 or 3) for each SNP, where k is predicted using the available data. We compare our method to four genotyping algorithms (GenCall, GenoSNP, Illuminus and OptiCall) on several Illumina data sets that include samples from the HapMap project where the true genotypes are known in advance. All methods were found to have high overall accuracy (> 98%), with KRLMM consistently amongst the best. At low minor allele frequency, the KRLMM, OptiCall and GenoSNP algorithms were observed to be consistently more accurate than GenCall and Illuminus on our test data. Conclusions Methods that tailor their approach to calling low frequency variants by either varying the number of clusters (KRLMM) or using information from other SNPs (OptiCall and GenoSNP) offer improved accuracy over methods that do not (GenCall and Illuminus). The KRLMM algorithm is implemented in the open-source crlmm package distributed via the Bioconductor project (http://www.bioconductor.org).

2014-01-01

210

Quantum Capacity under Adversarial Quantum Noise: Arbitrarily Varying Quantum Channels  

NASA Astrophysics Data System (ADS)

We investigate entanglement transmission over an unknown channel in the presence of a third party (called the adversary), which is enabled to choose the channel from a given set of memoryless but non-stationary channels without informing the legitimate sender and receiver about the particular choice that he made. This channel model is called an arbitrarily varying quantum channel (AVQC). We derive a quantum version of Ahlswede's dichotomy for classical arbitrarily varying channels. This includes a regularized formula for the common randomness-assisted capacity for entanglement transmission of an AVQC. Quite surprisingly and in contrast to the classical analog of the problem involving the maximal and average error probability, we find that the capacity for entanglement transmission of an AVQC always equals its strong subspace transmission capacity. These results are accompanied by different notions of symmetrizability (zero-capacity conditions) as well as by conditions for an AVQC to have a capacity described by a single-letter formula. In the final part of the paper the capacity of the erasure-AVQC is computed and some light shed on the connection between AVQCs and zero-error capacities. Additionally, we show by entirely elementary and operational arguments motivated by the theory of AVQCs that the quantum, classical, and entanglement-assisted zero-error capacities of quantum channels are generically zero and are discontinuous at every positivity point.

Ahlswede, Rudolf; Bjelakovi?, Igor; Boche, Holger; Nötzel, Janis

2013-01-01

211

A Varying-e Brane World Cosmology  

NASA Astrophysics Data System (ADS)

We study a varying electric charge brane world cosmology in the RS2 model obtained from a varying-speed-of-light brane world cosmology by redefining the system of units. We elaborate conditions under which the flatness problem and the cosmological constant problem can be resolved by such cosmological model.

Youm, Donam

212

Novel shock absorber features varying yield strengths  

NASA Technical Reports Server (NTRS)

A shock absorbent webbing of partially drawn synthetic strands is arranged in sections of varying density related to the varying mass of the human body. This is contoured to protect the body at points of contact, when subjected to large acceleration or deceleration forces.

Geier, D. J.

1964-01-01

213

New varying speed of light theories  

Microsoft Academic Search

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying-c, dispelling the myth that the constancy of c is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity

João Magueijo

2003-01-01

214

Real-world solutions for orthopaedic on-call problems.  

PubMed

An increasing percentage of emergency departments are reporting an inadequate number of on-call specialists. This situation is causing a growing crisis in emergency department on-call coverage for patients requiring orthopaedic care. Many orthopaedic surgeons are electing to opt out of emergency department on-call service. For many reasons, including a dwindling supply of eager participants, more medical groups are finding it difficult to fulfill their on-call obligations. This problem demands a variety of strategies to address the multiple causative factors that occur in practice settings. Initially, it may be necessary to incentivize on-call service so more surgeons are willing to participate. Incentives may include improving the group governance and bylaws to avoid confusion on the rules for providing on-call coverage. The on-call experience may require financial improvements, outsourcing with locum tenens, or a complete restructuring of the on-call arrangement with the formation of a hospitalist program. PMID:22301265

Agnew, Samuel G; Blotter, Robert H; Kosmatka, Paul K; Rudin, Guy J

2012-01-01

215

Intelligent call admission control for wideband CDMA cellular systems  

Microsoft Academic Search

In this paper, we propose intelligent call admission control for wideband code-division multiple-access (CDMA) cellular systems to support differentiated quality-of-service (QoS) requirements, guarantee the forced termination probability of handoffs, and maximize the spectrum utilization. The intelligent call admission controller (ICAC) contains a fuzzy call admission processor to make admission decision for a call request by considering QoS measures such as

Scott Shen; Chung-Ju Chang; ChingYao Huang; Qi Bi

2004-01-01

216

Distributed call admission control in mobile\\/wireless networks  

Microsoft Academic Search

The major focus of this paper is distributed call admission control in mobile\\/wireless networks, the purpose of which is to limit the call handoff dropping probability in loss systems or the cell overload probability in lossless systems. Handoff dropping or cell overload are consequences of congestion in wireless networks. Our call admission control algorithm takes into consideration the number of

Mahmoud Naghshineh; Mischa Schwartz

1996-01-01

217

Change point detection based on call detail records  

Microsoft Academic Search

In this paper we propose a method for combining wavelet denoising and sequential approach for detecting change points on mobile phone based on detailed call records. The Minmax method is used to estimate the thresholds of frequency and call duration for denoising. This work is useful to enhance homeland security, detecting unwanted calls (e.g., spam) and commercial purposes. For validation

Huiqi Zhang; Ram Dantu; João W. Cangussu

2009-01-01

218

Mobile cluster based call admission control in wireless mobile networks  

Microsoft Academic Search

For an efficient and effective connection admission control scheme in wireless mobile network, we propose mobile clustering based distributed call admission control (MC-DCA) scheme, which uses passive reservation information for predicting user mobility. Also, our scheme evaluates the prediction time that considers the call duration time and call dwell time before handoff neighbor cells for evaluating the overload probability.

Jeong-Jae Won; Eui-seok Hwang; Hyong-Woo Lee; Choong-Ho Cho

2003-01-01

219

A fuzzy call admission control scheme in wireless networks  

Microsoft Academic Search

Scarcity of the spectrum resource and mobility of users make quality of service (QoS) provision a critical issue in wireless networks. This paper presents a fuzzy call admission control scheme to meet the requirement of the QoS. A performance measure is formed as a weighted linear function of new call and handoff call blocking probabilities. Simulation compares the proposed fuzzy

Yufeng Ma; Shenguang Gong; Xiulin Hu; Yunyu Zhang

2007-01-01

220

Probabilistic call admission control in wireless multiservice networks  

Microsoft Academic Search

A new probabilistic call admission control scheme is proposed for multiservice wireless networks. The new scheme gradually suppresses the admission rate of the new calls and of the calls of each service class (SC) supported considering their priorities independently. The scheme is examined both for a single SC and for multiple SCs under general conditions. The analysis employs Markov chain

Dimitrios G. Stratogiannis; Georgios I. Tsiropoulos; John D. Kanellopoulos; Panayotis G. Cottis

2009-01-01

221

Enhancing Security using Calling Activity for Wireless Networks  

Microsoft Academic Search

In this paper, we present a detection technique based on Bayes decision rule to identify a group of especially harmful insider attackers - masqueraders. In this technique, we exploit the calling patterns demonstrated by mobile users in mobile cellular networks. Specifically, we formulate the intrusion detection problem as a multi-feature two-class pattern classification problem. Call duration time, call inactivity period

Bo Sun; Yang Xiao; Ruhai Wang; Sghaier Guizani

2006-01-01

222

Complex-Network Modeling of a Call Network  

Microsoft Academic Search

Recently, real-life data have revealed that the number of calls originating from or received by a telephone number in a network follows a power-law distribution. They show that a few telephone numbers make or receive a very large number of calls, whereas a large number of telephone numbers make or receive very few calls. The data have overthrown the general

Wai M. Tam; Francis C. M. Lau; Chi K. Tse

2009-01-01

223

Performance Analysis of the Outbound Call Management System  

Microsoft Academic Search

The Outbound Call Management (OCM) system automatically dials phone numbers from a long predetermined list for human agents. A technique is provided to determine the number of calls to launch for the Outbound Call Management system to achieve a good agent efficiency performance measure, giving the queuing tolerance level. Subsequently, an approximate method is introduced that calculates the efficiency of

Mohsen Sarraf

1989-01-01

224

The Call for an African University: A Critical Reflection  

ERIC Educational Resources Information Center

In this paper, we draw on philosophy (particularly African philosophy) to analyse the call for an African university. The call for an African university may be viewed as a call that insists that all critical and transformative educators in Africa embrace an indigenous African worldview and root their nation's educational paradigms in an indigenous…

van Wyk, Berte; Higgs, Philip

2007-01-01

225

CULTURAL TENSIONS - EXPLORING CALL CENTRES IN THE PUBLIC SECTOR  

Microsoft Academic Search

The mostly private sector literature on call centre work suggests two distinct images: electronic sweatshops and customer focus (Deery & Kinnie 2002). In the public sector, call centres have become widespread as governments import private sector management practices. Under the rubric of New Public Management (NPM) contestability, and client focus require call centres and other public services to compare or

Eve Anderson; Amanda Pyman; Julian Teicher

2007-01-01

226

Call graph construction in object-oriented languages  

Microsoft Academic Search

Interprocedural analyses enable optimizing compilers to more precisely model the effects of non-inlined procedure calls, potentially resulting in substantial increases in application performance. Applying interprocedural analysis to programs written in object-oriented or functional languages is complicated by the difficulty of constructing an accurate program call graph. This paper presents a parameterized algorithmic framework for call graph construction in the presence

David Grove; Greg DeFouw; Jeffrey Dean; Craig Chambers

1997-01-01

227

Operator bias in software-aided bat call identification  

PubMed Central

Software-aided identification facilitates the handling of large sets of bat call recordings, which is particularly useful in extensive acoustic surveys with several collaborators. Species lists are generated by “objective” automated classification. Subsequent validation consists of removing any species not believed to be present. So far, very little is known about the identification bias introduced by individual validation of operators with varying degrees of experience. Effects on the quality of the resulting data may be considerable, especially for bat species that are difficult to identify acoustically. Using the batcorder system as an example, we compared validation results from 21 volunteer operators with 1–26 years of experience of working on bats. All of them validated identical recordings of bats from eastern Austria. The final outcomes were individual validated lists of plausible species. A questionnaire was used to enquire about individual experience and validation procedures. In the course of species validation, the operators reduced the software's estimate of species richness. The most experienced operators accepted the smallest percentage of species from the software's output and validated conservatively with low interoperator variability. Operators with intermediate experience accepted the largest percentage, with larger variability. Sixty-six percent of the operators, mainly with intermediate and low levels of experience, reintroduced species to their validated lists which had been identified by the automated classification, but were finally excluded from the unvalidated lists. These were, in many cases, rare and infrequently recorded species. The average dissimilarity of the validated species lists dropped with increasing numbers of recordings, tending toward a level of ˜20%. Our results suggest that the operators succeeded in removing false positives and that they detected species that had been wrongly excluded during automated classification. Thus, manual validation of the software's unvalidated output is indispensable for reasonable results. However, although application seems easy, software-aided bat call identification requires an advanced level of operator experience. Identification bias during validation is a major issue, particularly in studies with more than one participant. Measures should be taken to standardize the validation process and harmonize the results of different operators.

Fritsch, Georg; Bruckner, Alexander

2014-01-01

228

Flexible work in call centres: Working hours, work-life conflict & health  

Microsoft Academic Search

Call-centre workers encounter major psychosocial pressures, including high work intensity and undesirable working hours. Little is known, however, about whether these pressures vary with employment status and how they affect work-life conflict and health. Questionnaire data were collected from 179 telephone operators in Sydney, Australia, of whom 124 (69.3%) were female and 54 (30.2%) were male. Ninety-three (52%) were permanent

Philip Bohle; Harold Willaby; Michael Quinlan; Maria McNamara

2011-01-01

229

Statistical Methods with Varying Coefficient Models  

PubMed Central

The varying coefficient models are very important tool to explore the dynamic pattern in many scientific areas, such as economics, finance, politics, epidemiology, medical science, ecology and so on. They are natural extensions of classical parametric models with good interpretability and are becoming more and more popular in data analysis. Thanks to their flexibility and interpretability, in the past ten years, the varying coefficient models have experienced deep and exciting developments on methodological, theoretical and applied sides. This paper gives a selective overview on the major methodological and theoretical developments on the varying coefficient models.

Fan, Jianqing; Zhang, Wenyang

2008-01-01

230

Female preferences for spectral call properties in the western genetic lineage of Cope's gray treefrog (Hyla chrysoscelis)  

PubMed Central

Female frogs discriminate among potential mates based on individual variation in male advertisement calls. While considerable data have accumulated allowing comparisons of female preference functions among species, we still lack fundamental knowledge about how and why the shapes of preference functions for particular call properties vary among populations within all but a few species. Here, we report results from a study aimed at describing female preference functions for spectral call properties in Cope’s gray treefrog (Hyla chrysoscelis). Widespread throughout the eastern half of North America, Cope’s gray treefrog is the diploid member of the cryptic diploid-tetraploid Hyla versicolor species complex, and its populations are divided into two distinct genetic lineages (eastern and western). In this study of a western lineage population, we recorded and analyzed the spectral properties of 1000 advertisement calls from 50 males and conducted two-choice phonotaxis experiments to estimate a population-level preference function. Females preferred calls with average frequencies over calls with frequencies that were 2 or 3 semitones (1.4 or 2.1 standard deviations, respectively) lower than the population mean. We observed no behavioral discrimination between calls with average and higher-than-average frequencies. Preferences discriminating against low-frequency calls were weak and were abolished by attenuating the preferred average call by 3 dB. We discuss these results in light of previous studies of eastern lineage populations, geographic variation in female preference functions, and the potential adaptive value of discriminating against calls with low frequencies.

Schrode, Katrina M.; Ward, Jessica L.; Velez, Alejandro

2012-01-01

231

Contact Calls of the Northern and Southern White Rhinoceros Allow for Individual and Species Identification  

PubMed Central

Inter-individual relationships particularly in socially living mammals often require a well-developed communication system. Vocal and olfactory signals are the most important for the communication of rhinos, however, their vocal communication has been investigated to a very limited extent so far. White rhinos have the most developed social system out of all the rhinoceros species and vocal signals might therefore play an important role in their social interactions. We recorded repetitive contact pant calls from six captive northern white rhinos (Ceratotherium cottoni) and 14 captive and free-ranging southern white rhinos (Ceratotherium simum) and examined if they transmit information about individual identity, species, social context and age class. Discriminant analyses revealed that a high percentage of the pant calls of both species could be classified to a correct individual. We calculated signature information capacity of pant calls recorded from adult animals in isolation at 3.19 bits for the northern white rhinos and at 3.15 bits for the southern white rhinos, which can potentially allow for a vocal discrimination of nine individuals of both species. We found that pant calls varied by species. Northern white rhinos had longer calls and also differed from the southern white rhinos in several frequency parameters of their calls. We also analysed the pant calls of southern white rhinos for the differences between the age classes and between social contexts in which they were recorded. Our results show that pant calls carry information about individual, species, age class and context. The ability to recognize this information would allow rhinos, in addition to olfactory cues, to communicate with highly increased accuracy. A better understanding of communication of white rhinos has potential practical use in their management and conservation particularly because of the low breeding success of white rhinos in captivity.

Cinkova, Ivana; Policht, Richard

2014-01-01

232

Contact calls of the northern and southern white rhinoceros allow for individual and species identification.  

PubMed

Inter-individual relationships particularly in socially living mammals often require a well-developed communication system. Vocal and olfactory signals are the most important for the communication of rhinos, however, their vocal communication has been investigated to a very limited extent so far. White rhinos have the most developed social system out of all the rhinoceros species and vocal signals might therefore play an important role in their social interactions. We recorded repetitive contact pant calls from six captive northern white rhinos (Ceratotherium cottoni) and 14 captive and free-ranging southern white rhinos (Ceratotherium simum) and examined if they transmit information about individual identity, species, social context and age class. Discriminant analyses revealed that a high percentage of the pant calls of both species could be classified to a correct individual. We calculated signature information capacity of pant calls recorded from adult animals in isolation at 3.19 bits for the northern white rhinos and at 3.15 bits for the southern white rhinos, which can potentially allow for a vocal discrimination of nine individuals of both species. We found that pant calls varied by species. Northern white rhinos had longer calls and also differed from the southern white rhinos in several frequency parameters of their calls. We also analysed the pant calls of southern white rhinos for the differences between the age classes and between social contexts in which they were recorded. Our results show that pant calls carry information about individual, species, age class and context. The ability to recognize this information would allow rhinos, in addition to olfactory cues, to communicate with highly increased accuracy. A better understanding of communication of white rhinos has potential practical use in their management and conservation particularly because of the low breeding success of white rhinos in captivity. PMID:24901244

Cinková, Ivana; Policht, Richard

2014-01-01

233

Divergence of a stereotyped call in northern resident killer whales.  

PubMed

Northern resident killer whale pods (Orcinus orca) have distinctive stereotyped pulsed call repertoires that can be used to distinguish groups acoustically. Repertoires are generally stable, with the same call types comprising the repertoire of a given pod over a period of years to decades. Previous studies have shown that some discrete pulsed calls can be subdivided into variants or subtypes. This study suggests that new stereotyped calls may result from the gradual modification of existing call types through subtypes. Vocalizations of individuals and small groups of killer whales were collected using a bottom-mounted hydrophone array in Johnstone Strait, British Columbia in 2006 and 2007. Discriminant analysis of slope variations of a predominant call type, N4, revealed the presence of four distinct call subtypes. Similar to previous studies, there was a divergence of the N4 call between members of different matrilines of the same pod. However, this study reveals that individual killer whales produced multiple subtypes of the N4 call, indicating that divergence in the N4 call is not the result of individual differences, but rather may indicate the gradual evolution of a new stereotyped call. PMID:21361462

Grebner, Dawn M; Parks, Susan E; Bradley, David L; Miksis-Olds, Jennifer L; Capone, Dean E; Ford, John K B

2011-02-01

234

Individual Distinctiveness in Call Types of Wild Western Female Gorillas  

PubMed Central

Individually distinct vocalizations play an important role in animal communication, allowing call recipients to respond differentially based on caller identity. However, which of the many calls in a species' repertoire should have more acoustic variability and be more recognizable is less apparent. One proposed hypothesis is that calls used over long distances should be more distinct because visual cues are not available to identify the caller. An alternative hypothesis proposes that close calls should be more recognizable because of their importance in social interactions. To examine which hypothesis garners more support, the acoustic variation and individual distinctiveness of eight call types of six wild western gorilla (Gorilla gorilla) females were investigated. Acoustic recordings of gorilla calls were collected at the Mondika Research Center (Republic of Congo). Acoustic variability was high in all gorilla calls. Similar high inter-individual variation and potential for identity coding (PIC) was found for all call types. Discriminant function analyses confirmed that all call types were individually distinct (although for call types with lowest sample size - hum, grumble and scream - this result cannot be generalized), suggesting that neither the distance at which communication occurs nor the call social function alone can explain the evolution of identity signaling in western gorilla communication.

Salmi, Roberta; Hammerschmidt, Kurt; Doran-Sheehy, Diane M.

2014-01-01

235

The Barbados Emergency Ambulance Service: High Frequency of Nontransported Calls  

PubMed Central

Objectives. There are no published studies on the Barbados Emergency Ambulance Service and no assessment of the calls that end in nontransported individuals. We describe reasons for the nontransport of potential clients. Methods. We used the Emergency Medical Dispatch (Medical Priority Dispatch System) instrument, augmented with five local call types, to collect information on types of calls. The calls were categorised under 7 headings. Correlations between call types and response time were calculated. Results. Most calls were from the category medical (54%). Nineteen (19%) percent of calls were in the non-transported category. Calls from call type Cancelled accounted for most of these and this was related to response time, while Refused service was inversely related (P = 0.01). Conclusions. The Barbados Ambulance Service is mostly used by people with a known illness and for trauma cases. One-fifth of calls fall into a category where the ambulance is not used often due to cancellation which is related to response time. Other factors such as the use of alternative transport are also important. Further study to identify factors that contribute to the non-transported category of calls is necessary if improvements in service quality are to be made.

Phillips, Sherwin E.; Gaskin, Pamela S.; Byer, David; Cadogan, W. L.; Brathwaite, Andrew; Nielsen, Anders L.

2012-01-01

236

The barbados emergency ambulance service: high frequency of nontransported calls.  

PubMed

Objectives. There are no published studies on the Barbados Emergency Ambulance Service and no assessment of the calls that end in nontransported individuals. We describe reasons for the nontransport of potential clients. Methods. We used the Emergency Medical Dispatch (Medical Priority Dispatch System) instrument, augmented with five local call types, to collect information on types of calls. The calls were categorised under 7 headings. Correlations between call types and response time were calculated. Results. Most calls were from the category medical (54%). Nineteen (19%) percent of calls were in the non-transported category. Calls from call type Cancelled accounted for most of these and this was related to response time, while Refused service was inversely related (P = 0.01). Conclusions. The Barbados Ambulance Service is mostly used by people with a known illness and for trauma cases. One-fifth of calls fall into a category where the ambulance is not used often due to cancellation which is related to response time. Other factors such as the use of alternative transport are also important. Further study to identify factors that contribute to the non-transported category of calls is necessary if improvements in service quality are to be made. PMID:23198147

Phillips, Sherwin E; Gaskin, Pamela S; Byer, David; Cadogan, W L; Brathwaite, Andrew; Nielsen, Anders L

2012-01-01

237

Campbell's Monkeys Use Affixation to Alter Call Meaning  

PubMed Central

Human language has evolved on a biological substrate with phylogenetic roots deep in the primate lineage. Here, we describe a functional analogy to a common morphological process in human speech, affixation, in the alarm calls of free-ranging adult Campbell's monkeys (Cercopithecus campbelli campbelli). We found that male alarm calls are composed of an acoustically variable stem, which can be followed by an acoustically invariable suffix. Using long-term observations and predator simulation experiments, we show that suffixation in this species functions to broaden the calls' meaning by transforming a highly specific eagle alarm to a general arboreal disturbance call or by transforming a highly specific leopard alarm call to a general alert call. We concluded that, when referring to specific external events, non-human primates can generate meaningful acoustic variation during call production that is functionally equivalent to suffixation in human language.

Ouattara, Karim; Lemasson, Alban; Zuberbuhler, Klaus

2009-01-01

238

Joint call admission control algorithm for reducing call blocking\\/dropping probability in heterogeneous wireless networks supporting multihoming  

Microsoft Academic Search

A heterogeneous wireless network supporting multihoming gives multi-mode terminals the flexibility to be simultaneously connected to more than one radio access technologies (RATs). Existing joint call admission control (JCAC) algorithms designed for heterogeneous wireless networks block or drop an incoming call when none of the available individual RATs in the heterogeneous network has enough bandwidth to support the incoming call.

Olabisi E. Falowo

2010-01-01

239

Individual differences and repeatability in vocal production: stress-induced calling exposes a songbird's personality.  

PubMed

Recent research in songbirds has demonstrated that male singing behavior varies systematically with personality traits such as exploration and risk taking. Here we examine whether the production of bird calls, in addition to bird songs, is repeatable and related to exploratory behavior, using the black-capped chickadee (Poecile atricapillus) as a model. We assessed the exploratory behavior of individual birds in a novel environment task. We then recorded the vocalizations and accompanying motor behavior of both male and female chickadees, over the course of several days, in two different contexts: a control condition with no playback and a stressful condition where chick-a-dee mobbing calls were played to individual birds. We found that several vocalizations and behaviors were repeatable within both a control and a stressful context, and across contexts. While there was no relationship between vocal output and exploratory behavior in the control context, production of alarm and chick-a-dee calls in the stressful condition was positively associated with exploratory behavior. These findings are important because they show that bird calls, in addition to bird song, are an aspect of personality, in that calls are consistent both within and across contexts, and covary with other personality measures (exploration). PMID:21928067

Guillette, Lauren M; Sturdy, Christopher B

2011-11-01

240

Modeling synchronized calling behavior of Japanese tree frogs  

NASA Astrophysics Data System (ADS)

We experimentally observed synchronized calling behavior of male Japanese tree frogs Hyla japonica; namely, while isolated single frogs called nearly periodically, a pair of interacting frogs called synchronously almost in antiphase or inphase. In this study, we propose two types of phase-oscillator models on different degrees of approximations, which can quantitatively explain the phase and frequency properties in the experiment. Moreover, it should be noted that, although the second model is obtained by fitting to the experimental data of the two synchronized states, the model can also explain the transitory dynamics in the interactive calling behavior, namely, the shift from a transient inphase state to a stable antiphase state. We also discuss the biological relevance of the estimated parameter values to calling behavior of Japanese tree frogs and the possible biological meanings of the synchronized calling behavior.

Aihara, Ikkyu

2009-07-01

241

Mutual selection in time-varying networks  

NASA Astrophysics Data System (ADS)

Time-varying networks play an important role in the investigation of the stochastic processes that occur on complex networks. The ability to formulate the development of the network topology on the same time scale as the evolution of the random process is important for a variety of applications, including the spreading of diseases. Past contributions have investigated random processes on time-varying networks with a purely random attachment mechanism. The possibility of extending these findings towards a time-varying network that is driven by mutual attractiveness is explored in this paper. Mutual attractiveness models are characterized by a linking function that describes the probability of the existence of an edge, which depends mutually on the attractiveness of the nodes on both ends of that edge. This class of attachment mechanisms has been considered before in the fitness-based complex networks literature but not on time-varying networks. Also, the impact of mutual selection is investigated alongside opinion formation and epidemic outbreaks. We find closed-form solutions for the quantities of interest using a factorizable linking function. The voter model exhibits an unanticipated behavior as the network never reaches consensus in the case of mutual selection but stays forever in its initial macroscopic configuration, which is a further piece of evidence that time-varying networks differ markedly from their static counterpart with respect to random processes that take place on them. We also find that epidemic outbreaks are accelerated by uncorrelated mutual selection compared to previously considered random attachment.

Hoppe, K.; Rodgers, G. J.

2013-10-01

242

Distributed call admission control in mobile\\/wireless networks  

Microsoft Academic Search

The major focus of this paper is distributed call admission control in mobile\\/wireless networks the purpose of which is to limit the call hand-off dropping probability in loss systems or the cell overload probability in lossless systems. Hand-off dropping or cell overload are consequences of congestion in wireless networks. Our call admission control algorithm takes into consideration the number of

Mahmoud Naghshineh; Mischa Schwartz

1995-01-01

243

A novel dynamic call admission control policy for wireless network  

Microsoft Academic Search

To address the issue of resource scarcity in wireless communication, a novel dynamic call admission control scheme for wireless\\u000a mobile network was proposed. The scheme established a reward computing model of call admission of wireless cell based on Markov\\u000a decision process, dynamically optimized call admission process according to the principle of maximizing the average system\\u000a rewards. Extensive simulations were conducted

Guo-sheng Huang; Zhi-gang Chen; Qing-hua Li; Ming Zhao; Zhen Guo

2010-01-01

244

Interference based Call Admission Control for Wireless Ad Hoc Networks  

Microsoft Academic Search

In this paper, we propose a call admission control mechanism for wireless ad hoc networks called interference-based call admission control (iCAC). iCAC is unique in that it does not treat interference uniformly instead classifies interference based on estimates of the position of the interfering nodes. iCAC relies on two novel techniques: (1) estimation of position of the interfering nodes (2)

K. N. Sridhar; Mun Choon Chan

2006-01-01

245

Computing call-blocking probabilities in LEO satellite constellations  

Microsoft Academic Search

We present an analytical model for computing call-blocking probabilities in a low Earth orbit (LEO) satellite network that carries voice calls. Both satellite-fixed and Earth-fixed constellations with interorbit links and handoffs are considered. We assume a single beam per satellite. Also, we assume that call arrivals are Poisson with a fixed arrival rate that is independent of the geographic area.

Abdul Halim Zaim; Harry G. Perros; George N. Rouskas

2003-01-01

246

IBM Research Report An Assessment of Call Graph Construction Algorithms  

Microsoft Academic Search

Abstract A large number of call graph construction algorithms for object-oriented and functional languages have been proposed, each embodying different tradeoffs between analysis cost and call graph precision. In this paper, we present a unifying framework,for understanding call graph construction algorithms and an empirical comparison,of a representative set of algorithms. We first present a general parameterized algorithm that encompasses,many,well-known and

David Grove; Craig Chambers

2000-01-01

247

optiCall: a robust genotype-calling algorithm for rare, low-frequency and common variants  

PubMed Central

Motivation: Existing microarray genotype-calling algorithms adopt either SNP-by-SNP (SNP-wise) or sample-by-sample (sample-wise) approaches to calling. We have developed a novel genotype-calling algorithm for the Illumina platform, optiCall, that uses both SNP-wise and sample-wise calling to more accurately ascertain genotypes at rare, low-frequency and common variants. Results: Using data from 4537 individuals from the 1958 British Birth Cohort genotyped on the Immunochip, we estimate the proportion of SNPs lost to downstream analysis due to false quality control failures, and rare variants misclassified as monomorphic, is only 1.38% with optiCall, in comparison to 3.87, 7.85 and 4.09% for Illuminus, GenoSNP and GenCall, respectively. We show that optiCall accurately captures rare variants and can correctly account for SNPs where probe intensity clouds are shifted from their expected positions. Availability and implementation: optiCall is implemented in C++ for use on UNIX operating systems and is available for download at http://www.sanger.ac.uk/resources/software/opticall/. Contact: optiCall@sanger.ac.uk

Shah, T. S.; Liu, J. Z.; Floyd, J. A. B.; Morris, J. A.; Wirth, N.; Barrett, J. C.; Anderson, C. A.

2012-01-01

248

naiveBayesCall: an efficient model-based base-calling algorithm for high-throughput sequencing.  

PubMed

Immense amounts of raw instrument data (i.e., images of fluorescence) are currently being generated using ultra high-throughput sequencing platforms. An important computational challenge associated with this rapid advancement is to develop efficient algorithms that can extract accurate sequence information from raw data. To address this challenge, we recently introduced a novel model-based base-calling algorithm that is fully parametric and has several advantages over previously proposed methods. Our original algorithm, called BayesCall, significantly reduced the error rate, particularly in the later cycles of a sequencing run, and also produced useful base-specific quality scores with a high discrimination ability. Unfortunately, however, BayesCall is too computationally expensive to be of broad practical use. In this article, we build on our previous model-based approach to devise an efficient base-calling algorithm that is orders of magnitude faster than BayesCall, while still maintaining a comparably high level of accuracy. Our new algorithm is called naive-BayesCall, and it utilizes approximation and optimization methods to achieve scalability. We describe the performance of naiveBayesCall and demonstrate how improved base-calling accuracy may facilitate de novo assembly and SNP detection when the sequence coverage depth is low to moderate. PMID:21385040

Kao, Wei-Chun; Song, Yun S

2011-03-01

249

Effect modification by time-varying covariates.  

PubMed

Marginal structural models (MSMs) allow estimation of effect modification by baseline covariates, but they are less useful for estimating effect modification by evolving time-varying covariates. Rather, structural nested models (SNMs) were specifically designed to estimate effect modification by time-varying covariates. In their paper, Petersen et al. (Am J Epidemiol 2007;166:985-993) describe history-adjusted MSMs as a generalized form of MSM and argue that history-adjusted MSMs allow a researcher to easily estimate effect modification by time-varying covariates. However, history-adjusted MSMs can result in logically incompatible parameter estimates and hence in contradictory substantive conclusions. Here the authors propose a more restrictive definition of history-adjusted MSMs than the one provided by Petersen et al. and compare the advantages and disadvantages of using history-adjusted MSMs, as opposed to SNMs, to examine effect modification by time-dependent covariates. PMID:17875581

Robins, James M; Hernán, Miguel A; Rotnitzky, Andrea

2007-11-01

250

Speaker adaptation using discriminative linear regression on time-varying mean parameters in trended HMM  

Microsoft Academic Search

In this letter, we report our recent work on applications of the combined maximum likelihood linear regression (MLLR) and the minimum classification error training (MCE) approach to estimating the time-varying polynomial Gaussian mean functions in the trended hidden Markov model (HMM). We call this integrated approach the minimum classification error linear regression (MCELR), which has been developed and implemented in

Rathinavelu Chengalvarayan

1998-01-01

251

Contribution of Io-Raised Tides to Europa's Diurnally-Varying Surface Stresses.  

National Technical Information Service (NTIS)

Europa's icy surface records a rich history of geologic activity, Several features appear to be tectonic in origin and may have formed in response to Europa's daily-varying tidal stress (I). Strike-slip faults and arcuate features called cycloids have bot...

A. R. Rhoden M. Manga T. A. Hurford

2011-01-01

252

Singularities of varying light speed cosmologies  

NASA Astrophysics Data System (ADS)

We study the possible singularities of isotropic cosmological models that have a varying speed of light as well as a varying gravitational constant. The field equations typically reduce to two dimensional systems which are then analyzed both by dynamical systems techniques in phase space and by applying the method of asymptotic splittings. In the general case we find initially expanding closed models which recollapse to a future singularity and open universes that are eternally expanding towards the future. The precise nature of the singularities is also discussed.

Miritzis, John; Cotsakis, Spiros

2007-05-01

253

Solar mass-varying neutrino oscillations.  

PubMed

We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs is independent of how the suppression of neutrino mass caused by the acceleron-matter couplings varies with density. Measurements of MeV and lower energy solar neutrinos will provide a rigorous test of the idea. PMID:16384133

Barger, V; Huber, Patrick; Marfatia, Danny

2005-11-18

254

Game Experience May Vary: Understanding Play  

Microsoft Academic Search

Why do we call it game research and not play research? For the last decade of videogame studies, most of the attention has\\u000a been paid to games as formal entities. At first, games seem easier to understand: they generally have clear rules and goals.\\u000a They would be perfect machineries with formal mechanics if it was not for one factor: humans

Gonzalo Frasca

2009-01-01

255

The Varied Uses of Readability Measurement.  

ERIC Educational Resources Information Center

Readability formulas have varied uses. In education they are used to match children's reading ability to the difficulty level of material, select stories and books for classroom use and for individual students' particular needs, select textbooks and other reading materials, aid educational research, and check reading materials of newly literate…

Fry, Edward

256

Time-varying joint distribution through copulas  

Microsoft Academic Search

This paper deals with the analysis of temporal dependence in multivariate time series. The dependence structure between the marginal series is modelled through the use of copulas which, unlike the correlation matrix, give a complete description of the joint distribution. The param- eters of the copula function vary through time following certain evolution equations depending on their previous values and

M. Concepcion Ausin; Hedibert F. Lopes

2010-01-01

257

High explosive detonations in varying oxygen atmospheres  

Microsoft Academic Search

Small spheres of PBX9404 and TNT were detonted in atmospheres of varying oxygen content to study the magnitude of the effects of oxygen on afterburn of high explosive (HE) detonation products (DPs). Each of the fireballs (FBs) formed by the HEDPs was observed by high-speed cameras and radiometers in the visible and near infrared. It was found that afterburn domintes

F. R. Kovar; K. R. Trigger; L. G. Guymon; J. R. Harvey

1982-01-01

258

Double-smoothing for varying coefficient models  

Microsoft Academic Search

Moderation analyses are widely used in biomedical and psychosocial research to investigate differential treatment effects, with moderators frequently identified through testing the significance of the interaction between the predictor and the potential moderator under strong parametric assumptions. Without imposing any parametric forms on how the moderators may affect the relationship between predictors and responses, varying coefficient models address this fundamental

Wan Tang; Guoxin Zuo; Hua He

2011-01-01

259

Extended Boussinesq equations for rapidly varying topography  

Microsoft Academic Search

We developed a new Boussinesq-type model which extends the equations of Madsen and Sørensen [1992. A new form of the Boussinesq equations with improved linear dispersion characteristics. Part 2. A slowly varying bathymetry. Coastal Engineering 18, 183–204.] by including both bottom curvature and squared bottom slope terms. Numerical experiments were conducted for wave reflection from the Booij's [1983. A note

Gunwoo Kim; Changhoon Lee; Kyung-Duck Suh

2009-01-01

260

Relaxation Assessment with Varied Structured Milieu (RELAX).  

ERIC Educational Resources Information Center

Describes Relaxation Assessment with Varied Structured Milieu (RELAX), a clinical program designed to assess the degree to which an individual is able to demonstrate self-control for overall general relaxation. The program is designed for use with the Cassel Biosensors biofeedback equipment. (JAC)

Cassel, Russell N.; Cassel, Susie L.

1983-01-01

261

Time-Varying Dynamic Bayesian Networks  

Microsoft Academic Search

Directed graphical models such as Bayesian networks are a favored formalism for modeling the dependency structures in complex multivariate systems such as those encountered in biology and neural science. When a system is undergo- ing dynamic transformation, temporally rewiring networks are needed for cap- turing the dynamic causal influences between covariates. In this paper, we pro- pose time-varying dynamic Bayesian

Le Song; Mladen Kolar; Eric P. Xing

262

Faculty Sense of Religious Calling at a Christian University  

ERIC Educational Resources Information Center

Sense of calling is often described with language steeped in religious tradition. It is variously described as a spiritual process or endeavor or as a summons by God to fulfill a specific purpose or task in life. This ethnographic case study examines how 18 senior faculty members of differing faith traditions expressed a religious sense of calling

Swezey, James A.

2009-01-01

263

Why We All Need Call Waiting on Our Phones  

NASA Astrophysics Data System (ADS)

Have you ever noticed that you can go all day without a single call on your phone and then suddenly you get two calls at once? This is actually not as uncommon as it sounds and there is a mathematical reason for why we should expect it to happen, believe it or not.

Higbie, Jack

2013-05-01

264

28 CFR 540.102 - Monitoring of inmate telephone calls.  

Code of Federal Regulations, 2013 CFR

...Monitoring of inmate telephone calls. The Warden shall establish procedures that enable...institution and to protect the public. The Warden must provide notice to the inmate of...properly placed call to an attorney. The Warden shall notify an inmate of the...

2013-07-01

265

Evaluating a CALL Software on the Learning of English Prepositions  

ERIC Educational Resources Information Center

This study assessed the effectiveness of using a CALL lesson (Computer Assisted Language Learning) over a conventional lesson to facilitate learning of English prepositions at Bario, Malaysia. CALL was developed by the Ministry of Education, Malaysia as support material to enhance learning of English prepositions. Both the conventional and the…

Ngu, Bing Hiong; Rethinasamy, Soubakeavathi

2006-01-01

266

“Cold calling” in psychiatric follow up studies: is it justified?  

Microsoft Academic Search

Background: The ethics of cold calling—visiting subjects at home without prior appointment agreed—in follow up research studies has received little attention although it is perceived to be quite common. We examined the ethical implications of cold calling in a study of subjects with defined neurotic disorders followed up 12 years after initial assessment carried out to determine outcome in terms

P Tyrer; H Seivewright; B Ferguson; T Johnson

2003-01-01

267

Thinning Schemes for Call Admission Control in Wireless Networks  

Microsoft Academic Search

AbstractDIn this paper, we present new call admission control schemes, the thinning schemes, which smoothly reduce the traffic admission rates. Performance analysis is carried out and new analytical results are obtained. It demonstrates that the thinning schemes can be used to derive many known call admission control schemes.

Yuguang Fang

2003-01-01

268

Call admission control in wireless networks: A comprehensive survey  

Microsoft Academic Search

Radio resource management (RRM) plays a major role in Quality of Service (QoS) provisioning for wireless communication systems. The performance of RRM techniques has a direct impact on each user's individual performance and on the overall network performance. Arriving (new and handoff) calls are granted\\/denied access to the network by the call admission scheme (CAC) based on predefined criteria, taking

Mohamed Hossam Ahmed

2005-01-01

269

Increasing the efficiency of a Brazilian Emergency response Call Center  

Microsoft Academic Search

This paper presents solutions to increase efficiency and reduce response times at an emergency call center in the southernmost state of Brazil, Rio Grande do Sul. Utilizing macro-ergonomic design, personal staff interviews and questionnaires served to illuminate the major shortcomings of the call center's operating system. Solutions are proposed to the two identified critical issues with the system. To address

Andrei Bieger; Gabriel Borges; Sigrid Kranz; Connor McGowan; Kevin Meehan; L. G. Mancuso; Stephanie Guerlain; L. B. de Macedo Guimaraes

2009-01-01

270

Sound imaging of nocturnal animal calls in their natural habitat.  

PubMed

We present a novel method for imaging acoustic communication between nocturnal animals. Investigating the spatio-temporal calling behavior of nocturnal animals, e.g., frogs and crickets, has been difficult because of the need to distinguish many animals' calls in noisy environments without being able to see them. Our method visualizes the spatial and temporal dynamics using dozens of sound-to-light conversion devices (called "Firefly") and an off-the-shelf video camera. The Firefly, which consists of a microphone and a light emitting diode, emits light when it captures nearby sound. Deploying dozens of Fireflies in a target area, we record calls of multiple individuals through the video camera. We conduct two experiments, one indoors and the other in the field, using Japanese tree frogs (Hyla japonica). The indoor experiment demonstrates that our method correctly visualizes Japanese tree frogs' calling behavior. It has confirmed the known behavior; two frogs call synchronously or in anti-phase synchronization. The field experiment (in a rice paddy where Japanese tree frogs live) also visualizes the same calling behavior to confirm anti-phase synchronization in the field. Experimental results confirm that our method can visualize the calling behavior of nocturnal animals in their natural habitat. PMID:21584762

Mizumoto, Takeshi; Aihara, Ikkyu; Otsuka, Takuma; Takeda, Ryu; Aihara, Kazuyuki; Okuno, Hiroshi G

2011-09-01

271

How can I help you? User instructions in telephone calls  

Microsoft Academic Search

We a small corpus of instructions given in phone calls to customers who need support for programming their universal remote control, to make it suitable for their particular TV set VCR, Audio, etc. Typically, in these calls the operator or 'agent' coaches the client while the client is performing actions with the equipment (turning it on, pressing buttons and codes,

Michael Steehouder; Daniel Hartman

2003-01-01

272

Convertible calls and corporate taxes under asymmetric information  

Microsoft Academic Search

This paper develops a signalling model of call of convertible securities (bonds or preferred stock) in the presence of corporate taxes and asymmetric information about future earnings. In equilibrium, managers with relatively unfavorable information call to force convertible holders to convert to common stock (in spite of the loss of corporate tax benefits if the convertibles are bonds), while those

Yong O. Kim; Jarl Kallberg

1998-01-01

273

Genotype and SNP calling from next-generation sequencing data  

Microsoft Academic Search

Meaningful analysis of next-generation sequencing (NGS) data, which are produced extensively by genetics and genomics studies, relies crucially on the accurate calling of SNPs and genotypes. Recently developed statistical methods both improve and quantify the considerable uncertainty associated with genotype calling, and will especially benefit the growing number of studies using low- to medium-coverage data. We review these methods and

Joshua S. Paul; Anders Albrechtsen; Rasmus Nielsen; Yun S. Song

2011-01-01

274

Enhancing Online CALL Design: The Case for Evaluation  

ERIC Educational Resources Information Center

Whilst the potential of online Computer Assisted Language Learning (CALL) in terms of access, immediacy and exposure is widely acknowledged, as yet remarkably little is known about its impact on the user population, be they language teachers or learners. Indeed, beyond its technological development, online CALL design is still affected by a dearth…

Hemard, Dominique

2004-01-01

275

Second Language Instructors and CALL: A Multidisciplinary Research Framework  

Microsoft Academic Search

The increasing importance of computer assisted language learning (CALL) in second language (L2) classes has added a new dimension to L2 research, and it has challenged scholars to find valid research methods and theoretical frameworks that can be applied in the analysis of the linguistic and social aspects of the interaction among students and instructors in CALL. Even though researchers

Gabriela C. Zapata

2004-01-01

276

Two-stage call admission control policy for LTE systems  

Microsoft Academic Search

In this paper, we evaluate a two-stage call admission control (CAC) policy for Long Term Evolution (LTE) Systems working along with packet scheduler (PS). The proposed two-stage admission scheme uses the quality the received signal as an indicator to estimate the amount of resources for each call in order to improve the performance of the overall network. Unlikely with other

Chrysovalantis Kosta; Toyin Sodunke; Majid Shateri; Rahim Tafazolli

2010-01-01

277

The Multidimensionality of Calling: Conceptualization, Measurement and a Bicultural Perspective  

ERIC Educational Resources Information Center

The experience of a calling may be seen as the ultimate form of subjective career success that has many positive consequences for individuals and organizations. We are here concerned with the conceptualization of a new multidimensional measure of calling, the MCM. In the first two studies we employed a qualitative approach and came up with five…

Hagmaier, Tamara; Abele, Andrea E.

2012-01-01

278

29 CFR 785.17 - On-call time.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false On-call time. 785.17 Section 785.17 Labor Regulations...HOURS WORKED Application of Principles Waiting Time § 785.17 On-call time. An employee who is required to remain on...

2013-07-01

279

AI in CALL--Artificially Inflated or Almost Imminent?  

ERIC Educational Resources Information Center

The application of techniques from artificial intelligence (AI) to CALL has commonly been referred to as intelligent CALL (ICALL). ICALL is only slightly older than the "CALICO Journal", and this paper looks back at a quarter century of published research mainly in North America and by North American scholars. This "inventory taking" will provide…

Schulze, Mathias

2008-01-01

280

Why We All Need Call Waiting on Our Phones  

ERIC Educational Resources Information Center

Have you ever noticed that you can go all day without a single call on your phone and then suddenly you get two calls at once? This is actually not as uncommon as it sounds and there is a mathematical reason for why we should expect it to happen, believe it or not.

Higbie, Jack

2013-01-01

281

Mutual selection in time-varying networks.  

PubMed

Time-varying networks play an important role in the investigation of the stochastic processes that occur on complex networks. The ability to formulate the development of the network topology on the same time scale as the evolution of the random process is important for a variety of applications, including the spreading of diseases. Past contributions have investigated random processes on time-varying networks with a purely random attachment mechanism. The possibility of extending these findings towards a time-varying network that is driven by mutual attractiveness is explored in this paper. Mutual attractiveness models are characterized by a linking function that describes the probability of the existence of an edge, which depends mutually on the attractiveness of the nodes on both ends of that edge. This class of attachment mechanisms has been considered before in the fitness-based complex networks literature but not on time-varying networks. Also, the impact of mutual selection is investigated alongside opinion formation and epidemic outbreaks. We find closed-form solutions for the quantities of interest using a factorizable linking function. The voter model exhibits an unanticipated behavior as the network never reaches consensus in the case of mutual selection but stays forever in its initial macroscopic configuration, which is a further piece of evidence that time-varying networks differ markedly from their static counterpart with respect to random processes that take place on them. We also find that epidemic outbreaks are accelerated by uncorrelated mutual selection compared to previously considered random attachment. PMID:24229223

Hoppe, K; Rodgers, G J

2013-10-01

282

Computer-assisted scheduling of radiology resident call.  

PubMed

The difficulties inherent in assigning an entire residency group fair and equivalent daily call prompted the development of a computerized scheduling program at The University of Texas at Houston. Written in COBOL, the program is run on a CDC mainframe computer. Logic parameters restrict the number and frequency of calls per month, and each resident is coded for five available call types at two university hospitals. The foundation of the program's operation is an arbitrary point scale applied to each call type determined by its difficulty and time commitment. Residents' point totals each month are roughly balanced within a prescribed range, with call exchanges made by the computer if necessary. The computer-generated schedules are flexible and equitable, require little manual correction, and save time for the chief resident and the residency secretary. PMID:3754853

Larson, T C; Larson, S L; Harle, T S

1986-05-01

283

Energy on call: a more efficient peaking system would exploit the advantages of energy storage, while conserving capital and resources  

Microsoft Academic Search

Energy demand varies with the seasons, the days of the week, and the hours of each day. The power industry must maintain generation, transmission, and distribution capacity to meet peak demands on call. A more efficient peaking system would exploit the advantages of energy storage, while conserving capital and resources. It has been estimated that 300 million barrels of oil

J. A. Casazza; T. R. Schneider; V. T. Sulzberger

1976-01-01

284

Common reasons why acne patients call the office.  

PubMed

Background: Communication between physicians and patients is essential to providing proper medical care. At times, patients leave visits with insufficiently addressed questions. These questions prompt patients to call the clinic for additional information, which disrupts the flow of care, delays proper treatment, and reduces patient satisfaction. Purpose: We aim to examine acne patients' post-visit questions to develop interventions to improve patient education and reduce call backs. Methods: A retrospective electronic medical record chart review was performed involving Wake Forest Baptist Health Dermatology clinic visits between October 1, 2012 and October 31, 2012. We identified acne patients using clinic visit notes and recorded their telephone calls to the clinic between October 1, 2012 and March 29, 2013. Results: Of 315 acne patients, 31 (9.8%) called the clinic. Isotretinoin was the subject of 66.7% of the calls, half of which involved questions about potential side effects. Other calls addressed topical medications, acne symptoms, and pharmacy requests. Limitations: The study involved one center and email and fax correspondence was not captured. Conclusions: We found gaps in communication sufficient to require patients to call in for support, specifically regarding oral isotretinoin treatment. Interventions to address these questions have the potential to improve quality of care. PMID:24852769

Barnes, Lauren E; Al-Dabagh, Amir; Huang, William W; Feldman, Steven R

2014-01-01

285

Spectrographic Analysis of Carrion Crow Calls and Their Detection  

NASA Astrophysics Data System (ADS)

In recent years, damage to agricultural products, livestock, and power transmission systems by crows is regarded as a serious problem; countermeasures against crow damage are urgently necessary. This paper proposed a method for detecting crow calls in various environmental sounds. If detection and discernment of crow calls were possible, various actions could be undertaken to prevent the damage. Wildlife call detection, not only that for crows, should be executed in extremely noisy environments. We then introduced both a spectrograph estimation technique with AR modeling in which AR coefficients are temporally smoothed and interpolated and a background noise elimination technique to obtain higher-quality crow call templates. The input sounds are compared with these templates by DP matching in the metric vector space of a logarithmic cepstrum. Every input sound whose minimal distance to the template database is less than the specified threshold value is detected as a crow call. The maximal detection performance can be obtained when five call templates in the template database are utilized; the implication is that carrion crows have five distinguishable call patterns. It is shown that the proposed method achieves 95% detection rate when 1.66% misdetection rate is allowed.

Shibuya, Hisashi; Yokota, Yasunari

286

Varied line-space gratings and applications  

SciTech Connect

This paper presents a straightforward analytical and numerical method for the design of a specific type of varied line-space grating system. The mathematical development will assume plane or nearly-plane spherical gratings which are illuminated by convergent light, which covers many interesting cases for synchrotron radiation. The gratings discussed will have straight grooves whose spacing varies across the principal plane of the grating. Focal relationships and formulae for the optical grating-pole-to-exist-slit distance and grating radius previously presented by other authors will be derived with a symbolic algebra system. It is intended to provide the optical designer with the tools necessary to design such a system properly. Finally, some possible advantages and disadvantages for application to synchrotron to synchrotron radiation beamlines will be discussed.

McKinney, W.R.

1991-07-15

287

The Thermal Collector With Varied Glass Covers  

NASA Astrophysics Data System (ADS)

The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

Luminosu, I.; Pop, N.

2010-08-01

288

Influence of socioeconomic factors on medically unnecessary ambulance calls  

PubMed Central

Background Unnecessary ambulance use has become a socioeconomic problem in Japan. We investigated the possible relations between socioeconomic factors and medically unnecessary ambulance calls, and we estimated the incremental demand for unnecessary ambulance use produced by socioeconomic factors. Methods We conducted a self-administered questionnaire-based survey targeting residents of Yokohama, Japan. The questionnaire included questions pertaining to socioeconomic characteristics, dichotomous choice method questions pertaining to ambulance calls in hypothetical nonemergency situations, and questions on the city's emergency medical system. The probit model was used to analyze the data. Results A total of 2,029 out of 3,363 targeted recipients completed the questionnaire (response rate, 60.3%). Probit regression analyses showed that several demographic and socioeconomic factors influence the decision to call an ambulance. Male respondents were more apt than female respondents to state that they would call an ambulance in nonemergency situations (p < 0.05). Age was an important factor influencing the hypothetical decision to call an ambulance (p < 0.05); elderly persons were more apt than younger persons to state that they would call an ambulance. Possession of a car and hesitation to use an ambulance negatively influenced the hypothetical decision to call an ambulance (p < 0.05). Persons who do not have a car were more likely than those with a car to state that they would call an ambulance in unnecessary situations. Conclusion Results of the study suggest that several socioeconomic factors, i.e., age, gender, household income, and possession of a car, influence a person's decision to call an ambulance in nonemergency situations. Hesitation to use an ambulance and knowledge of the city's primary emergency medical center are likely to be important factors limiting ambulance overuse. It was estimated that unnecessary ambulance use is increased approximately 10% to 20% by socioeconomic factors.

Kawakami, Chihiro; Ohshige, Kenji; Kubota, Katsuaki; Tochikubo, Osamu

2007-01-01

289

Cash management in a randomly varying environment  

Microsoft Academic Search

We study a cash management system, in which the distribution of the cash flow Xn in period n=1,2,… depends on the state In of a randomly varying environment. Sufficient conditions are found for the optimality of a simple transfer rule, generalizing and partially improving the well-known results for the classical case with i.i.d. cash flows. These and further structural results

Karl Hinderer; Karl-Heinz Waldmann

2001-01-01

290

ROC graphs with instance-varying costs  

Microsoft Academic Search

Receiver Operating Characteristics (ROC) graphs are a useful technique for organizing classifiers and visual- izing their performance. ROC graphs have been used in cost-sensitive learning because of the ease with which class skew and error cost information can be applied to them to yield cost-sensitive decisions. However, they have been criticized because of their inability to handle instance-varying costs; that

Tom Fawcett

2006-01-01

291

Dark energy from mass varying neutrinos  

NASA Astrophysics Data System (ADS)

We show that mass varying neutrinos (MaVaNs) can behave as a negative pressure fluid which could be the origin of the cosmic acceleration. We derive a model independent relation between the neutrino mass and the equation of state parameter of the neutrino dark energy, which is applicable for general theories of mass varying particles. The neutrino mass depends on the local neutrino density and the observed neutrino mass can exceed the cosmological bound on a constant neutrino mass. We discuss microscopic realizations of the MaVaN acceleration scenario, which involve a sterile neutrino. We consider naturalness constraints for mass varying particles, and find that both eV cut-offs and eV mass particles are needed to avoid fine-tuning. In microscopic realizations of this scenario with a sterile neutrino, these considerations give the sterile neutrino a maximum mass today of order an eV, which could be detectable at MiniBooNE. Because the sterile neutrino was much heavier at earlier times, constraints from big bang nucleosynthesis on additional states are not problematic. We consider regions of high neutrino density and find that the most likely place today to find neutrino masses which are significantly different from the neutrino masses in our solar system is in a supernova. The possibility of different neutrino mass in different regions of the galaxy and the local group could be significant for Z-burst models of ultra-high energy cosmic rays. We also consider the cosmology of and the constraints on the 'acceleron', the scalar field which is responsible for the varying neutrino mass, and briefly discuss neutrino density dependent variations in other constants, such as the fine structure constant.

Fardon, Rob; Nelson, Ann E.; Weiner, Neal

2004-10-01

292

Spatially varying dispersion to model breakthrough curves.  

PubMed

Often the water flowing in a karst conduit is a combination of contaminated water entering at a sinkhole and cleaner water released from the limestone matrix. Transport processes in the conduit are controlled by advection, mixing (dilution and dispersion), and retention-release. In this article, a karst transport model considering advection, spatially varying dispersion, and dilution (from matrix seepage) is developed. Two approximate Green's functions are obtained using transformation of variables, respectively, for the initial-value problem and for the boundary-value problem. A numerical example illustrates that mixing associated with strong spatially varying conduit dispersion can cause strong skewness and long tailing in spring breakthrough curves. Comparison of the predicted breakthrough curve against that measured from a dye-tracing experiment between Ames Sink and Indian Spring, Northwest Florida, shows that the conduit dispersivity can be as large as 400 m. Such a large number is believed to imply strong solute interaction between the conduit and the matrix and/or multiple flow paths in a conduit network. It is concluded that Taylor dispersion is not dominant in transport in a karst conduit, and the complicated retention-release process between mobile- and immobile waters may be described by strong spatially varying conduit dispersion. PMID:21143474

Li, Guangquan

2011-01-01

293

Correlates of negative physical health in call center shift workers.  

PubMed

The call center industry, a burgeoning sector is characterized by unique job demands, which render it susceptible to high attrition rates and negative health concerns. This study examined the relationship between job stress from interpersonal factors, job stress from work factors, coping, inadequate sleep, and negative physical health reports among call center shift workers (n = 239), a relatively under-researched population. Inadequate sleep and job stress from interpersonal factors were associated with negative physical health outcome for the participants in this study. Further, spending longer in the call center industry was associated with negative health outcome for the shift worker participants. PMID:23040668

Rameshbabu, Anjali; Reddy, Diane M; Fleming, Raymond

2013-05-01

294

A fuzzy call admission control scheme in wireless networks  

NASA Astrophysics Data System (ADS)

Scarcity of the spectrum resource and mobility of users make quality of service (QoS) provision a critical issue in wireless networks. This paper presents a fuzzy call admission control scheme to meet the requirement of the QoS. A performance measure is formed as a weighted linear function of new call and handoff call blocking probabilities. Simulation compares the proposed fuzzy scheme with an adaptive channel reservation scheme. Simulation results show that fuzzy scheme has a better robust performance in terms of average blocking criterion.

Ma, Yufeng; Gong, Shenguang; Hu, Xiulin; Zhang, Yunyu

2007-11-01

295

16. STONE MILL, ALSO CALLED LIGHTNINGSTRUCK HOUSE OR OLD PUMP ...  

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

16. STONE MILL, ALSO CALLED LIGHTNING-STRUCK HOUSE OR OLD PUMP HOUSE Photocopy of photograph, 1930s National Park Service, National Capital Region files - Dumbarton Oaks Park, Thirty-second & R Streets Northwest, Washington, District of Columbia, DC

296

47 CFR 90.241 - Radio call box operations.  

Code of Federal Regulations, 2010 CFR

...the transmitter after 2 minutes unless the central control station operator reactivates the timer cycle. (10) The central control station must include facilities that permit direct control of any call...

2009-10-01

297

47 CFR 90.241 - Radio call box operations.  

Code of Federal Regulations, 2010 CFR

...the transmitter after 2 minutes unless the central control station operator reactivates the timer cycle. (10) The central control station must include facilities that permit direct control of any call...

2010-10-01

298

47 CFR 10.510 - Call preemption prohibition.  

Code of Federal Regulations, 2010 CFR

...FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL MOBILE ALERT SYSTEM Equipment Requirements § 10.510 Call preemption...Devices marketed for public use under part 10 must not enable an Alert Message to preempt an active voice or data...

2010-10-01

299

47 CFR 10.510 - Call preemption prohibition.  

Code of Federal Regulations, 2012 CFR

...FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL MOBILE ALERT SYSTEM Equipment Requirements § 10.510 Call preemption...Devices marketed for public use under part 10 must not enable an Alert Message to preempt an active voice or data...

2012-10-01

300

47 CFR 10.510 - Call preemption prohibition.  

Code of Federal Regulations, 2011 CFR

...FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL MOBILE ALERT SYSTEM Equipment Requirements § 10.510 Call preemption...Devices marketed for public use under part 10 must not enable an Alert Message to preempt an active voice or data...

2011-10-01

301

76 FR 67747 - Interagency Autism Coordinating Committee; Call for Nominations  

Federal Register 2010, 2011, 2012, 2013

...National Institutes of Health Interagency Autism Coordinating Committee; Call for Nominations...with Public Law 112-32, The Combating Autism Reauthorization Act the Department of...to continue to support the Interagency Autism Coordinating Committee (IACC)...

2011-11-02

302

Call-Center Based Disease Management of Pediatric Asthmatics.  

National Technical Information Service (NTIS)

The purpose of this study is to examine a population-based intervention using preventive measures of a remote call-based asthma disease management program utilizing proactive education and monitoring. This intervention will be compared to a control popula...

J. M. Quinn

2005-01-01

303

Call-Center Based Disease Management of Pediatric Asthmatics.  

National Technical Information Service (NTIS)

The purpose of this study is to examine a population-based intervention using preventive measures of a remote call-based asthma disease management program utilizing proactive education and monitoring. This intervention will be compared to a control popula...

J. M. Quinn

2004-01-01

304

20. DETAIL OF GAS FIXTURE (CALLED 'CALLA LILY BRACKET'), MANUFACTURED ...  

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

20. DETAIL OF GAS FIXTURE (CALLED 'CALLA LILY BRACKET'), MANUFACTURED CIRCA 1855, SOUTH WALL OF SOUTHWEST ROOM, FIRST FLOOR - Ronald-Brennan House, 631 South Fifth Street, Louisville, Jefferson County, KY

305

47 CFR 10.510 - Call preemption prohibition.  

Code of Federal Regulations, 2013 CFR

...FEDERAL COMMUNICATIONS COMMISSION GENERAL WIRELESS EMERGENCY ALERTS Equipment Requirements § 10.510 Call preemption prohibition...Devices marketed for public use under part 10 must not enable an Alert Message to preempt an active voice or data...

2013-10-01

306

Front elevation of highlift pumping station. Colesville Road (also called ...  

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

Front elevation of high-lift pumping station. Colesville Road (also called U.S. Route 29 or Columbia Pike) is in foreground. - Robert B. Morse Water Filtration Plant, 10700 and 10701 Columbia Pike, Silver Spring, Montgomery County, MD

307

16. VIEW OF STRUCTURE NOW CALLED 'COMMANDER'S HOUSE,' LOOKING NORTHWEST ...  

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

16. VIEW OF STRUCTURE NOW CALLED 'COMMANDER'S HOUSE,' LOOKING NORTHWEST THROUGH THE LAUNCH AREA GATE Marilyn Ziemer, photographer, April 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

308

9. Excavation work at Pleasant Dam (now called Waddell Dam). ...  

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

9. Excavation work at Pleasant Dam (now called Waddell Dam). Photographer unknown, July, 22, 1926. Source: Maricopa County Municipal Water Conservation District Number One (MWD). - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

309

Mechanical Property Characterization of Intraply Hybrid Composites.  

National Technical Information Service (NTIS)

An investigation was conducted to characterize the mechanical properties of intraply hybrids made from graphite fiber/epoxy matrix (primary composites) hybridized with varying amounts of secondary composites made from S-glass or Kevlar 49 fibers. The test...

C. C. Chamis R. F. Lark J. H. Sinclair

1979-01-01

310

[Calling and mating behaviors of bamboo shoot borer Kumasia kumaso].  

PubMed

The calling and mating behaviors of Kumasia kumaso were studied in laboratory at (25 1) degrees C and (60 +/- 10) % RH under a cycle 14 L:10 D photo period, and the EAG response of male K. kumaso to female K. kumaso sex gland extracts was also tested. The calling and mating behaviors of K. kumaso could only be observed in scotophase. The females began calling at the first scotophase following emergence, and the peak of calling occurred during the second scotophase and decreased thereafter. The calling of the females commenced 0-4 h after dark, reached the maximum between the 5th and the 7th hour of the scotophase, and terminated during the last 1-2.5 h of the scotophase. Moth age had significant effects on the calling patterns. With increasing moth age, the onset time of calling advanced gradually, and the mean number of calling bouts as well as the calling length per bout had a gradual increase from calling day 1 to day 4 but decreased on day 5. The peak time and terminated time of calling advanced with increasing moth age. The mating of K. kumaso adults initiated during the first scotophase and terminated till the 5th scotophase following emergence, and the peak of mating was observed during the second scotophase. The peak of mating was observed 5.5-7.0 h after dark, and advanced with increasing moth age. Moth age affected the mean onset time of mating and the copulation duration significantly. With increasing moth age, the mean onset time of mating advanced, and the copulation duration decreased. Sex ratio had significant effects on the mating behavior as well. Treatment 2 female:1 male showed a significantly higher mating percentage, but an earlier onset time of mating and shorter copulation duration, as compared with treatment 1 female:1 male. The results of EAG test indicated that the male adults showed a significant EAG response to the sex gland extracts of 2-day-old virgin females. PMID:23479886

Shu, Jin-Ping; Teng, Ying; Zhang, Ai-Liang; Zhang, Ya-Bo; Deng, Shun; Wang, Hao-Jie

2012-12-01

311

Call matching in the quacking frog ( Crinia georgiana )  

Microsoft Academic Search

Males of the quacking frog Crinia georgiana produce calls consisting of 1–11 notes. Playback experiments using synthetic calls showed that males tend to match the number\\u000a of notes in 2-note and 4-note stimuli; however, males tended to produce more than 1 note in response to a 1-note stimulus\\u000a and fewer than 8 notes in response to an 8-note stimulus. Successive

H. Carl Gerhardt; J. Dale Roberts; Mark A. Bee; Joshua J. Schwartz

2000-01-01

312

Heterospecific alarm call recognition in a non-vocal reptile.  

PubMed

The ability to recognize and respond to the alarm calls of heterospecifics has previously been described only in species with vocal communication. Here we provide evidence that a non-vocal reptile, the Galápagos marine iguana (Amblyrhynchus cristatus), can eavesdrop on the alarm call of the Galápagos mockingbird (Nesomimus parvulus) and respond with anti-predator behaviour. Eavesdropping on complex heterospecific communications demonstrates a remarkable degree of auditory discrimination in a non-vocal species. PMID:17911047

Vitousek, Maren N; Adelman, James S; Gregory, Nathan C; Clair, James J H St

2007-12-22

313

On-call work and health: a review  

Microsoft Academic Search

Many professions in the fields of engineering, aviation and medicine employ this form of scheduling. However, on-call work has received significantly less research attention than other work patterns such as shift work and overtime hours. This paper reviews the current body of peer-reviewed, published research conducted on the health effects of on-call work The health effects studies done in the

Anne-Marie Nicol; Jackie S Botterill

2004-01-01

314

Infrasonic calls of the Asian elephant ( Elephas maximus )  

Microsoft Academic Search

Calls at frequencies below the range of human hearing were recorded from two groups of captive Asian elephants (Elephas maximus). Most of the calls ranged in frequency from 14 to 24 Hz, with durations of 10–15 s (Fig. 1). With the nearest elephant 5 m from the microphone, sound pressure levels were 85 to 90 dB (re 20 µPa). These

Katharine B. Payne; William R. Langbauer Jr; Elizabeth M. Thomas

1986-01-01

315

Modelling of confusions in aircraft call-signs  

Microsoft Academic Search

Air-traffic has grown rapidly in the last twenty years and concern has been mounting about the safety implications of mis-recognition of call-signs by both pilots and air-traffic controllers. This paper presents the results of a preliminary study into perceptual (i.e. non-cognitive) confusions in two closed vocabularies of the type used as aircraft call-signs. Conventional methods of subjective and objective testing

Stephen Cox; Lluis Vinagre

2004-01-01

316

A Call to Action: Reconnecting College Sports and Higher Education  

NSDL National Science Digital Library

On June 26, the Knight Foundation's Commission on Intercollegiate Athletics issued a report that calls for a number of sweeping reforms in collegiate athletics. Among other things, the report calls on college presidents to form a new coalition to reassert control of college sport and recommends banning corporate logos on school uniforms, barring teams that do not graduate at least 50 percent of their players from conference championships and postseason play, and banning legal gambling on collegiate athletics.

2001-01-01

317

Analytical model for multi agent - call admission in wireless networks  

Microsoft Academic Search

Resource allocation and its planning are major issues in wireless networks. Distributed call admission control requires calls to be admitted by considering local as well as global view of the network so as to reduce overall congestion. The paper proposes MA-CAC (Multi Agent-CAC) scheme which models a D-CAC problem using multiagent system (MAS) where each cell comprises of agents. These

Nupur Giri; Shrikant Bodhe

2007-01-01

318

Detecting Facial Expression by Concentration on Cellular Phone Call  

NASA Astrophysics Data System (ADS)

Because something to think about and conversation with someone disturb the attention to the car driving, decentralization of attention by the cellular phone call tends to decrease safety in driving. This paper presents an experimental result of the relation between the attention concentration on the cellular phone call and the change in the facial expression such as eye movements and blinks. Moreover, this paper describes a method of detecting the depth of the attention concentration from the facial expression change.

Takahashi, Kenichi; Yamamoto, Osami; Nakano, Tomoaki; Yamamoto, Shin

319

Alarm calls elicit predator-specific physiological responses  

PubMed Central

Glucocorticoids regulate glucose concentrations and responses to unpredictable events, while also modulating cognition. Juvenile Belding's ground squirrels (Urocitellus beldingi) learn to respond to whistle and trill alarm calls, warning of aerial and terrestrial predators, respectively, shortly after emerging from natal burrows at one month of age. Alarm calls can cause physiological reactions and arousal, and this arousal, coupled with watching adult responses, might help juveniles learn associations between calls and behavioural responses. I studied whether young show differential cortisol responses to alarm and non-alarm calls, using playbacks of U. beldingi whistles, trills, squeals (a conspecific control vocalization) and silent controls. Trills elicited very high cortisol responses, and, using an individual's response to the silent control as baseline, only their response to a trill was significantly higher than baseline. This cortisol increase would provide glucose for extended vigilance and escape efforts, which is appropriate for evading terrestrial predators which hunt for long periods. Although whistles do not elicit a cortisol response, previous research has shown that they do result in bradycardia, which enhances attention and information processing. This is a novel demonstration of two physiological responses to two alarm calls, each appropriate to the threats represented by the calls.

Mateo, Jill M.

2010-01-01

320

Responses of squirrel monkeys to their experimentally modified mobbing calls  

NASA Astrophysics Data System (ADS)

Previous acoustic analyses suggested emotion-correlated changes in the acoustic structure of squirrel monkey (Saimiri sciureus) vocalizations. Specifically, calls given in aversive contexts were characterized by an upward shift in frequencies, often accompanied by an increase in amplitude. In order to test whether changes in frequencies or amplitude are indeed relevant for conspecific listeners, playback experiments were conducted in which either frequencies or amplitude of mobbing calls were modified. Latency and first orienting response were measured in playback experiments with six adult squirrel monkeys. After broadcasting yaps with increased frequencies or amplitude, squirrel monkeys showed a longer orienting response towards the speaker than after the corresponding control stimuli. Furthermore, after broadcasting yaps with decreased frequencies or amplitude, squirrel monkeys showed a shorter orienting response towards the speaker than after the corresponding manipulated calls with higher frequencies or amplitude. These results suggest that changes in frequencies or amplitude were perceived by squirrel monkeys, indicating that the relationship between call structure and the underlying affective state of the caller agreed with the listener's assessment of the calls. However, a simultaneous increase in frequencies and amplitude did not lead to an enhanced response, compared to each single parameter. Thus, from the receiver's perspective, both call parameters may mutually replace each other.

Fichtel, Claudia; Hammerschmidt, Kurt

2003-05-01

321

New varying speed of light theories  

NASA Astrophysics Data System (ADS)

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying-c, dispelling the myth that the constancy of c is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity and light are not the same); locally Lorentz invariant VSL theories; theories exhibiting a colour-dependent speed of light; varying-c induced by extra dimensions (e.g. in the brane-world scenario); and field theories where VSL results from vacuum polarization or CPT violation. We show how VSL scenarios may solve the cosmological problems usually tackled by inflation, and also how they may produce a scale-invariant spectrum of Gaussian fluctuations, capable of explaining the WMAP data. We then review the connection between VSL and theories of quantum gravity, showing how 'doubly special' relativity has emerged as a VSL effective model of quantum space-time, with observational implications for ultra-high energy cosmic rays (UHECRs) and gamma ray bursts. Some recent work on the physics of 'black' holes and other compact objects in VSL theories is also described, highlighting phenomena associated with spatial (as opposed to temporal) variations in c. Finally, we describe the observational status of the theory. The evidence is currently slim—redshift dependence in the atomic fine structure, anomalies with UHECRs, and (to a much lesser extent) the acceleration of the universe and the WMAP data. The constraints (e.g. those arising from nucleosynthesis or geological bounds) are tight but not insurmountable. We conclude with the observational predictions of the theory and the prospects for its refutation or vindication.

Magueijo, João

2003-11-01

322

Linear Parameter Varying Control for Actuator Failure  

NASA Technical Reports Server (NTRS)

A robust linear parameter varying (LPV) control synthesis is carried out for an HiMAT vehicle subject to loss of control effectiveness. The scheduling parameter is selected to be a function of the estimates of the control effectiveness factors. The estimates are provided on-line by a two-stage Kalman estimator. The inherent conservatism of the LPV design is reducing through the use of a scaling factor on the uncertainty block that represents the estimation errors of the effectiveness factors. Simulations of the controlled system with the on-line estimator show that a superior fault-tolerance can be achieved.

Shin, Jong-Yeob; Wu, N. Eva; Belcastro, Christine; Bushnell, Dennis M. (Technical Monitor)

2002-01-01

323

3D-Printing Spatially Varying BRDFs.  

PubMed

A new method fabricates custom surface reflectance and spatially varying bidirectional reflectance distribution functions (svBRDFs). Researchers optimize a microgeometry for a range of normal distribution functions and simulate the resulting surface's effective reflectance. Using the simulation's results, they reproduce an input svBRDF's appearance by distributing the microgeometry on the printed material's surface. This method lets people print svBRDFs on planar samples with current 3D printing technology, even with a limited set of printing materials. It extends naturally to printing svBRDFs on arbitrary shapes. PMID:24808130

Rouiller, Olivier; Bickel, Bernd; Kautz, Jan; Matusik, Wojciech; Alexa, Marc

2013-01-01

324

Laser lithotripsy retropulsion varies with stone mass  

NASA Astrophysics Data System (ADS)

OBJECTIVES: We tested the hypothesis that retropulsion varies with stone size. METHODS: Stone phantoms of uniform cube dimensions were constructed and irradiated with Ho:YAG energy (0.5 J - 3.5 J). Displacement was measured. RESULTS: At any given pulse energy, retropulsion decreased as stone size increased, p<0.05. At any given stone size, retropulsion increased as pulse energy increased, p<0.05. CONCLUSIONS: A strategy of low pulse energy at high repetition rate is appropriate for ureteral stones. For larger bladder and renal stones, retropulsion is minimal even with high pulse energies. More study is warranted.

Robinson, Michael E.; Teichman, Joel M. H.

325

Kuramoto model with time-varying parameters  

NASA Astrophysics Data System (ADS)

We analyze the Kuramoto model generalized by explicit consideration of deterministically time-varying parameters. The oscillators' natural frequencies and/or couplings are influenced by external forces with constant or distributed strengths. A dynamics of the collective rhythms is observed, consisting of the external system superimposed on the autonomous one, a characteristic feature of many thermodynamically open systems. This deterministic, stable, continuously time-dependent, collective behavior is fully described, and the external impact to the original system is defined in both the adiabatic and the nonadiabatic limits.

Petkoski, Spase; Stefanovska, Aneta

2012-10-01

326

Progressive Fracture of Composite Structures  

NASA Technical Reports Server (NTRS)

A new approach is described for evaluating fracture in composite structures. This approach is independent of classical fracture mechanics parameters like fracture toughness. It relies on computational simulation and is programmed in a stand-alone integrated computer code. It is multiscale, multifunctional because it includes composite mechanics for the composite behavior and finite element analysis for predicting the structural response. It contains seven modules; layered composite mechanics (micro, macro, laminate), finite element, updating scheme, local fracture, global fracture, stress based failure modes, and fracture progression. The computer code is called CODSTRAN (Composite Durability Structural ANalysis). It is used in the present paper to evaluate the global fracture of four composite shell problems and one composite built-up structure. Results show that the composite shells and the built-up composite structure global fracture are enhanced when internal pressure is combined with shear loads.

Chamis, Christos C.; Minnetyan, Levon

2008-01-01

327

Optimizing power output by varying repetition tempo.  

PubMed

The effects of varying interrepetition rest and eccentric velocity on power output (PO) and the number of repetitions performed during a bench press set were examined in 24 college-aged resistance trained men. On 6 separate occasions, subjects performed a set of bench press at 80% 1 repetition maximum until volitional fatigue. For each of the 6 repetition tempo trials, the bench press set was paced by metronome to a unique repetition tempo involving a combination of the following: interrepetition rest of 0 or 4 seconds; eccentric velocity of 1 or 4 seconds and bottom rest of 0 or 3 seconds. The velocity of concentric contraction was maximal during all 6 tempo trials. During each trial, video data were captured to determine PO variables and number of successful repetitions completed at each tempo. One-way repeated measures analysis of variance showed tempos with a fast eccentric phase (1 second), and no bottom rest produced significantly greater (p ? 0.05) PO and repetitions than tempos involving slower eccentric velocity (4 seconds) or greater bottom rest (4 seconds). This combination of greater repetitions and PO resulted in a greater volume of work. Varying interrepetition rest (1 or 4 seconds) did not significantly affect PO or repetitions. The results of this study support the use of fast eccentric speed and no bottom rest during acute performance testing to maximize PO and number of repetitions during a set of bench press. PMID:21881531

Pryor, Riana R; Sforzo, Gary A; King, Deborah L

2011-11-01

328

Detecting skin colors under varying illumination  

NASA Astrophysics Data System (ADS)

Skin color has been used as an important cue for various human related computer vision applications. However, detecting skin colors under varying illumination is a challenging task, as the appearance of skin in an image highly depends on the illumination under which the image was taken. To this end, a method for detecting skin colors under varying illumination is proposed in this paper. First, spatial illumination variation is identified and the images are segmented into different regions with different illumination. Each illumination region of color images are corrected base on the illuminant estimated by a local edge-based color constancy algorithm. Then, the corrected images are transformed into a color-space, where statistical results on a skin dataset show that the skin color cluster and non-skin color clusters are separated. Finally, the skin colors are modeled under Bayesian decision framework and classified from non-skin colors. The experimental results show that the proposed method is robust to illumination variations.

Liu, Leyuan; Huang, Rui; Yang, Saiyong; Sang, Nong

2011-11-01

329

Transient, spatially varied groundwater recharge modeling  

NASA Astrophysics Data System (ADS)

The objective of this work is to integrate field data and modeling tools in producing temporally and spatially varying groundwater recharge in a pilot watershed in North Okanagan, Canada. The recharge modeling is undertaken by using the Richards equation based finite element code (HYDRUS-1D), ArcGIS™, ROSETTA, in situ observations of soil temperature and soil moisture, and a long-term gridded climate data. The public version of HYDUS-1D and another version with detailed freezing and thawing module are first used to simulate soil temperature, snow pack, and soil moisture over a one year experimental period. Statistical analysis of the results show both versions of HYDRUS-1D reproduce observed variables to the same degree. After evaluating model performance using field data and ROSETTA derived soil hydraulic parameters, the HYDRUS-1D code is coupled with ArcGIS™ to produce spatially and temporally varying recharge maps throughout the Deep Creek watershed. Temporal and spatial analysis of 25 years daily recharge results at various representative points across the study watershed reveal significant temporal and spatial variations; average recharge estimated at 77.8 ± 50.8 mm/year. Previous studies in the Okanagan Basin used Hydrologic Evaluation of Landfill Performance without any attempt of model performance evaluation, notwithstanding its inherent limitations. Thus, climate change impact results from this previous study and similar others, such as Jyrkama and Sykes (2007), need to be interpreted with caution.

Assefa, Kibreab Amare; Woodbury, Allan D.

2013-08-01

330

Controlling Contagion Processes in Time Varying Networks  

NASA Astrophysics Data System (ADS)

The vast majority of strategies aimed at controlling contagion and spreading processes on networks consider the connectivity pattern of the system as quenched. In this paper, we consider the class of activity driven networks to analytically evaluate how different control strategies perform in time-varying networks. We consider the limit in which the evolution of the structure of the network and the spreading process are simultaneous yet independent. We analyze three control strategies based on node's activity patterns to decide the removal/immunization of nodes. We find that targeted strategies aimed at the removal of active nodes outperform by orders of magnitude the widely used random strategies. In time-varying networks however any finite time observation of the network dynamics provides only incomplete information on the nodes' activity and does not allow the precise ranking of the most active nodes as needed to implement targeted strategies. Here we develop a control strategy that focuses on targeting the egocentric time-aggregated network of a small control group of nodes.The presented strategy allows the control of spreading processes by removing a fraction of nodes much smaller than the random strategy while at the same time limiting the observation time on the system.

Liu, Suyu; Perra, Nicola; Karsai, Marton; Vespignani, Alessandro

2013-03-01

331

Pulse register phonation in Diana monkey alarm calls  

NASA Astrophysics Data System (ADS)

The adult male Diana monkeys (Cercopithecus diana) produce predator-specific alarm calls in response to two of their predators, the crowned eagles and the leopards. The acoustic structure of these alarm calls is remarkable for a number of theoretical and empirical reasons. First, although pulsed phonation has been described in a variety of mammalian vocalizations, very little is known about the underlying production mechanism. Second, Diana monkey alarm calls are based almost exclusively on this vocal production mechanism to an extent that has never been documented in mammalian vocal behavior. Finally, the Diana monkeys' pulsed phonation strongly resembles the pulse register in human speech, where fundamental frequency is mainly controlled by subglottal pressure. Here, we report the results of a detailed acoustic analysis to investigate the production mechanism of Diana monkey alarm calls. Within calls, we found a positive correlation between the fundamental frequency and the pulse amplitude, suggesting that both humans and monkeys control fundamental frequency by subglottal pressure. While in humans pulsed phonation is usually considered pathological or artificial, male Diana monkeys rely exclusively on pulsed phonation, suggesting a functional adaptation. Moreover, we were unable to document any nonlinear phenomena, despite the fact that they occur frequently in the vocal repertoire of humans and nonhumans, further suggesting that the very robust Diana monkey pulse production mechanism has evolved for a particular functional purpose. We discuss the implications of these findings for the structural evolution of Diana monkey alarm calls and suggest that the restricted variability in fundamental frequency and robustness of the source signal gave rise to the formant patterns observed in Diana monkey alarm calls, used to convey predator information.

Riede, Tobias; Zuberbühler, Klaus

2003-05-01

332

BayesCall: A model-based base-calling algorithm for high-throughput short-read sequencing  

PubMed Central

Extracting sequence information from raw images of fluorescence is the foundation underlying several high-throughput sequencing platforms. Some of the main challenges associated with this technology include reducing the error rate, assigning accurate base-specific quality scores, and reducing the cost of sequencing by increasing the throughput per run. To demonstrate how computational advancement can help to meet these challenges, a novel model-based base-calling algorithm, BayesCall, is introduced for the Illumina sequencing platform. Being founded on the tools of statistical learning, BayesCall is flexible enough to incorporate various features of the sequencing process. In particular, it can easily incorporate time-dependent parameters and model residual effects. This new approach significantly improves the accuracy over Illumina's base-caller Bustard, particularly in the later cycles of a sequencing run. For 76-cycle data on a standard viral sample, phiX174, BayesCall improves Bustard's average per-base error rate by ?51%. The probability of observing each base can be readily computed in BayesCall, and this probability can be transformed into a useful base-specific quality score with a high discrimination ability. A detailed study of BayesCall's performance is presented here.

Kao, Wei-Chun; Stevens, Kristian; Song, Yun S.

2009-01-01

333

BayesCall: A model-based base-calling algorithm for high-throughput short-read sequencing.  

PubMed

Extracting sequence information from raw images of fluorescence is the foundation underlying several high-throughput sequencing platforms. Some of the main challenges associated with this technology include reducing the error rate, assigning accurate base-specific quality scores, and reducing the cost of sequencing by increasing the throughput per run. To demonstrate how computational advancement can help to meet these challenges, a novel model-based base-calling algorithm, BayesCall, is introduced for the Illumina sequencing platform. Being founded on the tools of statistical learning, BayesCall is flexible enough to incorporate various features of the sequencing process. In particular, it can easily incorporate time-dependent parameters and model residual effects. This new approach significantly improves the accuracy over Illumina's base-caller Bustard, particularly in the later cycles of a sequencing run. For 76-cycle data on a standard viral sample, phiX174, BayesCall improves Bustard's average per-base error rate by approximately 51%. The probability of observing each base can be readily computed in BayesCall, and this probability can be transformed into a useful base-specific quality score with a high discrimination ability. A detailed study of BayesCall's performance is presented here. PMID:19661376

Kao, Wei-Chun; Stevens, Kristian; Song, Yun S

2009-10-01

334

Earth's Atmosphere: Composition and structure  

NSDL National Science Digital Library

This module explores the composition of the earth's atmosphere, how temperature and pressure vary in the atmosphere, and the scientific developments that led to an understanding of these basic concepts.

Egger, Anne

2003-10-31

335

Haploid to diploid alignment for variation calling assessment  

PubMed Central

Motivation Variation calling is the process of detecting differences between donor and consensus DNA via high-throughput sequencing read mapping. When evaluating the performance of different variation calling methods, a typical scenario is to simulate artificial (diploid) genomes and sample reads from those. After variation calling, one can then compute precision and recall statistics. This works reliably on SNPs but on larger indels there is the problem of invariance: a predicted deletion/insertion can differ slightly from the true one, yet both make the same change to the genome. Also exactly correct predictions are rare, especially on larger insertions, so one should consider some notion of approximate predictions for fair comparison. Results We propose a full genome alignment-based strategy that allows for fair comparison of variation calling predictions: First, we apply the predicted variations to the consensus genome to create as many haploid genomes as are necessary to explain the variations. Second, we align the haploid genomes to the (aligned) artificial diploid genomes allowing arbitrary recombinations. The resulting haploid to diploid alignments tells how much the predictions differ from the true ones, solving the invariance issues in direct variation comparison. In an effort to make the approach scalable to real genomes, we develop a simple variant of the classical edit distance dynamic programming algorithm and apply the diagonal doubling technique to optimise the computation. We experiment with the approach on simulated predictions and also on real prediction data from a variation calling challenge.

2013-01-01

336

Combining calls from multiple somatic mutation-callers  

PubMed Central

Background Accurate somatic mutation-calling is essential for insightful mutation analyses in cancer studies. Several mutation-callers are publicly available and more are likely to appear. Nonetheless, mutation-calling is still challenging and there is unlikely to be one established caller that systematically outperforms all others. Therefore, fully utilizing multiple callers can be a powerful way to construct a list of final calls for one’s research. Results Using a set of mutations from multiple callers that are impartially validated, we present a statistical approach for building a combined caller, which can be applied to combine calls in a wider dataset generated using a similar protocol. Using the mutation outputs and the validation data from The Cancer Genome Atlas endometrial study (6,746 sites), we demonstrate how to build a statistical model that predicts the probability of each call being a somatic mutation, based on the detection status of multiple callers and a few associated features. Conclusion The approach allows us to build a combined caller across the full range of stringency levels, which outperforms all of the individual callers.

2014-01-01

337

Genotype calling and haplotyping in parent-offspring trios  

PubMed Central

Emerging sequencing technologies allow common and rare variants to be systematically assayed across the human genome in many individuals. In order to improve variant detection and genotype calling, raw sequence data are typically examined across many individuals. Here, we describe a method for genotype calling in settings where sequence data are available for unrelated individuals and parent-offspring trios and show that modeling trio information can greatly increase the accuracy of inferred genotypes and haplotypes, especially on low to modest depth sequencing data. Our method considers both linkage disequilibrium (LD) patterns and the constraints imposed by family structure when assigning individual genotypes and haplotypes. Using simulations, we show that trios provide higher genotype calling accuracy across the frequency spectrum, both overall and at hard-to-call heterozygous sites. In addition, trios provide greatly improved phasing accuracy—improving the accuracy of downstream analyses (such as genotype imputation) that rely on phased haplotypes. To further evaluate our approach, we analyzed data on the first 508 individuals sequenced by the SardiNIA sequencing project. Our results show that our method reduces the genotyping error rate by 50% compared with analysis using existing methods that ignore family structure. We anticipate our method will facilitate genotype calling and haplotype inference for many ongoing sequencing projects.

Chen, Wei; Li, Bingshan; Zeng, Zhen; Sanna, Serena; Sidore, Carlo; Busonero, Fabio; Kang, Hyun Min; Li, Yun; Abecasis, Goncalo R.

2013-01-01

338

[A relational database to store Poison Centers calls].  

PubMed

Italian Poison Centers answer to approximately 100,000 calls per year. Potentially, this activity is a huge source of data for toxicovigilance and for syndromic surveillance. During the last decade, surveillance systems for early detection of outbreaks have drawn the attention of public health institutions due to the threat of terrorism and high-profile disease outbreaks. Poisoning surveillance needs the ongoing, systematic collection, analysis, interpretation, and dissemination of harmonised data about poisonings from all Poison Centers for use in public health action to reduce morbidity and mortality and to improve health. The entity-relationship model for a Poison Center relational database is extremely complex and not studied in detail. For this reason, not harmonised data collection happens among Italian Poison Centers. Entities are recognizable concepts, either concrete or abstract, such as patients and poisons, or events which have relevance to the database, such as calls. Connectivity and cardinality of relationships are complex as well. A one-to-many relationship exist between calls and patients: for one instance of entity calls, there are zero, one, or many instances of entity patients. At the same time, a one-to-many relationship exist between patients and poisons: for one instance of entity patients, there are zero, one, or many instances of entity poisons. This paper shows a relational model for a poison center database which allows the harmonised data collection of poison centers calls. PMID:17124355

Barelli, Alessandro; Biondi, Immacolata; Tafani, Chiara; Pellegrini, Aristide; Soave, Maurizio; Gaspari, Rita; Annetta, Maria Giuseppina

2006-01-01

339

Voice over internet protocol with prepaid calling card solutions  

NASA Astrophysics Data System (ADS)

The VoIP technology is growing up rapidly, it has big network impact on PT Telkom Indonesia, the bigger telecommunication operator in Indonesia. Telkom has adopted VoIP and one other technology, Intelligent Network (IN). We develop those technologies together in one service product, called Internet Prepaid Calling Card (IPCC). IPCC is becoming new breakthrough for the Indonesia telecommunication services especially on VoIP and Prepaid Calling Card solutions. Network architecture of Indonesia telecommunication consists of three layer, Local, Tandem and Trunck Exchange layer. Network development researches for IPCC architecture are focus on network overlay hierarchy, Internet and PSTN. With this design hierarchy the goal of Interworking PSTN, VoIP and IN calling card, become reality. Overlay design for IPCC is not on Trunck Exchange, this is the new architecture, these overlay on Tandem and Local Exchange, to make the faster call processing. The nodes added: Gateway (GW) and Card Management Center (CMC) The GW do interfacing between PSTN and Internet Network used ISDN-PRA and Ethernet. The other functions are making bridge on circuit (PSTN) with packet (VoIP) based and real time billing process. The CMC used for data storage, pin validation, report activation, tariff system, directory number and all the administration transaction. With two nodes added the IPCC service offered to the market.

Gunadi, Tri

2001-07-01

340

Time varying arctic climate change amplification  

SciTech Connect

During the past 130 years the global mean surface air temperature has risen by about 0.75 K. Due to feedbacks -- including the snow/ice albedo feedback -- the warming in the Arctic is expected to proceed at a faster rate than the global average. Climate model simulations suggest that this Arctic amplification produces warming that is two to three times larger than the global mean. Understanding the Arctic amplification is essential for projections of future Arctic climate including sea ice extent and melting of the Greenland ice sheet. We use the temperature records from the Arctic stations to show that (a) the Arctic amplification is larger at latitudes above 700 N compared to those within 64-70oN belt, and that, surprisingly; (b) the ratio of the Arctic to global rate of temperature change is not constant but varies on the decadal timescale. This time dependence will affect future projections of climate changes in the Arctic.

Chylek, Petr [Los Alamos National Laboratory; Dubey, Manvendra K [Los Alamos National Laboratory; Lesins, Glen [DALLHOUSIE U; Wang, Muyin [NOAA/JISAO

2009-01-01

341

Inference of temporally varying Bayesian Networks  

PubMed Central

Motivation: When analysing gene expression time series data, an often overlooked but crucial aspect of the model is that the regulatory network structure may change over time. Although some approaches have addressed this problem previously in the literature, many are not well suited to the sequential nature of the data. Results: Here, we present a method that allows us to infer regulatory network structures that may vary between time points, using a set of hidden states that describe the network structure at a given time point. To model the distribution of the hidden states, we have applied the Hierarchical Dirichlet Process Hidden Markov Model, a non-parametric extension of the traditional Hidden Markov Model, which does not require us to fix the number of hidden states in advance. We apply our method to existing microarray expression data as well as demonstrating is efficacy on simulated test data. Contact: thomas.thorne@imperial.ac.uk

Thorne, Thomas; Stumpf, Michael P. H.

2012-01-01

342

Varying Fundamental Constants: A Dynamical Systems Approach  

NASA Astrophysics Data System (ADS)

Theory of dynamical systems offers a possibility of investigating the space of all possible solutions. In the context of simple cosmological models such like Varying Speed of Light Friedman- Robertson-Walker (VSL FRW) models there exists a systematic method of reducing field equations to certain two-dimensional dynamical system. One of the features of this reduction is the possibility of representing the model as a Hamiltonian system in which the properties of the potential function V(X) can serve as a tool for qualitative classification of possible evolutions of a(t). Some important features like resolution of the flatness problem, existence of event horizons near the singularity can be visualized as domains on the phase-space. Then one is able to see how large is the class of solutions (labelled by the initial conditions) leading to the desired property.

Biesiada, Marek

343

Climate dynamics: Why does climate vary?  

NASA Astrophysics Data System (ADS)

In recent years, climate change has become a major focus of public and political discussion. Ongoing scientific inquiry, revolving predominantly around understanding the anthropogenic effects of rising greenhouse gas levels, coupled with how successfully findings are communicated to the public, has made climate science both contentious and exigent. In the AGU monograph Climate Dynamics: Why Does Climate Vary?, editors De-Zheng Sun and Frank Bryan reinforce the importance of investigating the complex dynamics that underlie the natural variability of the climate system. Understanding this complexity—particularly how the natural variability of climate may enhance or mask anthropogenic warming—could have important consequences for the future. In this interview, Eos talks to De-Zheng Sun.

Schultz, Colin

2011-08-01

344

Qualitative analysis of universes with varying alpha  

NASA Astrophysics Data System (ADS)

Assuming a Friedmann universe which evolves with a power-law scale factor, a = t n, we analyse the phase space of the system of equations that describes a time-varying fine structure 'constant', ?, in the Bekenstein-Sandvik-Barrow-Magueijo generalization of general relativity. We have classified all the possible behaviours of ?(t) in ever-expanding universes with different n and find new exact solutions for ?(t). We find the attractor points in the phase space for all n. In general, ? will be a non-decreasing function of time that increases logarithmically in time during a period when the expansion is dust dominated (n = 2/3), but becomes constant when n > 2/3. This includes the case of negative-curvature domination (n = 1). ? also tends rapidly to a constant when the expansion scale factor increases exponentially. A general set of conditions is established for ? to become asymptotically constant at late times in an expanding universe.

Barrow, John D.; Mota, David F.

2002-12-01

345

An ETAS model with varying productivity rates  

NASA Astrophysics Data System (ADS)

We present an epidemic type aftershock sequenc (ETAS) model where the offspring rates vary both spatially and temporally. This is achieved by distinguishing between those space-time volumes where the interpoint space and time distances are small, and those where they are considerably larger. We also question the nature of the background component in the ETAS model. Is it simply a temporal boundary correction (t = 0) or does it represent an additional tectonic process not described by the aftershock component? The form of these stochastic models should not be considered to be fixed. As we accumulate larger and better earthquake catalogues, GPS data, strain rates, etc., we have the ability to ask more complex questions about the nature of the process. By fitting modified models consistent with such questions, we should gain a better insight into the earthquake process. Hence, we consider a sequence of incrementally modified ETAS type models rather than `the' ETAS model.

Harte, D. S.

2014-05-01

346

An ETAS model with varying productivity rates  

NASA Astrophysics Data System (ADS)

We present an epidemic type aftershock sequenc (ETAS) model where the offspring rates vary both spatially and temporally. This is achieved by distinguishing between those space-time volumes where the interpoint space and time distances are small, and those where they are considerably larger. We also question the nature of the background component in the ETAS model. Is it simply a temporal boundary correction (t = 0) or does it represent an additional tectonic process not described by the aftershock component? The form of these stochastic models should not be considered to be fixed. As we accumulate larger and better earthquake catalogues, GPS data, strain rates, etc., we have the ability to ask more complex questions about the nature of the process. By fitting modified models consistent with such questions, we should gain a better insight into the earthquake process. Hence, we consider a sequence of incrementally modified ETAS type models rather than `the' ETAS model.

Harte, D. S.

2014-07-01

347

Chimpanzee Alarm Call Production Meets Key Criteria for Intentionality  

PubMed Central

Determining the intentionality of primate communication is critical to understanding the evolution of human language. Although intentional signalling has been claimed for some great ape gestural signals, comparable evidence is currently lacking for their vocal signals. We presented wild chimpanzees with a python model and found that two of three alarm call types exhibited characteristics previously used to argue for intentionality in gestural communication. These alarm calls were: (i) socially directed and given to the arrival of friends, (ii) associated with visual monitoring of the audience and gaze alternations, and (iii) goal directed, as calling only stopped when recipients were safe from the predator. Our results demonstrate that certain vocalisations of our closest living relatives qualify as intentional signals, in a directly comparable way to many great ape gestures. We conclude that our results undermine a central argument of gestural theories of language evolution and instead support a multimodal origin of human language.

Schel, Anne Marijke; Townsend, Simon W.; Machanda, Zarin; Zuberbuhler, Klaus; Slocombe, Katie E.

2013-01-01

348

Chimpanzee alarm call production meets key criteria for intentionality.  

PubMed

Determining the intentionality of primate communication is critical to understanding the evolution of human language. Although intentional signalling has been claimed for some great ape gestural signals, comparable evidence is currently lacking for their vocal signals. We presented wild chimpanzees with a python model and found that two of three alarm call types exhibited characteristics previously used to argue for intentionality in gestural communication. These alarm calls were: (i) socially directed and given to the arrival of friends, (ii) associated with visual monitoring of the audience and gaze alternations, and (iii) goal directed, as calling only stopped when recipients were safe from the predator. Our results demonstrate that certain vocalisations of our closest living relatives qualify as intentional signals, in a directly comparable way to many great ape gestures. We conclude that our results undermine a central argument of gestural theories of language evolution and instead support a multimodal origin of human language. PMID:24146908

Schel, Anne Marijke; Townsend, Simon W; Machanda, Zarin; Zuberbühler, Klaus; Slocombe, Katie E

2013-01-01

349

Characteristics of calls to the Israeli hotline during the Intifada.  

PubMed

The present study examined the help-seeking characteristics of callers to the ten Israeli hotline centers during the Intifada - the Palestinian uprising in the Israeli administered territories. The research method combined quantitative and qualitative analyses of the volunteers' written reports. The quantitative analysis was conducted on a sample of 21,315 structured forms, and the qualitative content analysis was carried out on a sample of 498 verbal descriptions of calls. The quantitative analysis revealed a U-shaped curve illustrating the frequency of Intifada-related calls in relation to the time of the study. The qualitative analysis showed that the main complaints of the callers were focused on direct and masked manifestations of anxiety and feelings of helplessness. The implications of the findings are discussed in terms of understanding the unique psychological response to a new kind of stress, as seen from the perspective of calls to a hotline. PMID:17514506

Gilat, Itzhak; Latzer, Yael

2007-08-01

350

Individual right whales call louder in increased environmental noise  

PubMed Central

The ability to modify vocalizations to compensate for environmental noise is critical for successful communication in a dynamic acoustic environment. Many marine species rely on sound for vital life functions including communication, navigation and feeding. The impacts of significant increases in ocean noise levels from human activities are a current area of concern for the conservation of marine mammals. Here, we document changes in calling behaviour by individual endangered North Atlantic right whales (Eubalaena glacialis) in increased background noise. Right whales, like several bird and primate species, respond to periods of increased noise by increasing the amplitude of their calls. This behaviour may help maintain the communication range with conspecifics during periods of increased noise. These call modifications have implications for conservation efforts for right whales, affecting both the way whales use sound to communicate and our ability to detect them with passive acoustic monitoring systems.

Parks, Susan E.; Johnson, Mark; Nowacek, Douglas; Tyack, Peter L.

2011-01-01

351

Selected Aspects of the eCall Emergency Notification System  

NASA Astrophysics Data System (ADS)

The article describes problems associated with the road collision detection for the purpose of the automatic emergency call. At the moment collision is detected, the eCall device installed in the vehicle will automatically make contact with Emergency Notification Centre and send the set of essential information on the vehicle and the place of the accident. To activate the alarm, the information about the deployment of the airbags will not be used, because connection of the eCall device might interfere with the vehicle’s safety systems. It is necessary to develop a method enabling detection of the road collision, similar to the one used in airbag systems, and based on the signals available from the acceleration sensors.

Kaminski, Tomasz; Nowacki, Gabriel; Mitraszewska, Izabella; Niezgoda, Micha?; Kruszewski, Miko?aj; Kaminska, Ewa; Filipek, Przemys?aw

2012-02-01

352

Varying capacities for replication of rat adipocyte precursor clones and adipose tissue growth.  

PubMed Central

Rat adipocyte precursor populations contain clones varying in capacity for replication. In this study we explored factors controlling the frequency of clones of varying replicative capacities (clonal composition). We also explored the relationship between this frequency and fat depot growth. In perirenal and epididymal depots clonal composition was identical bilaterally; perirenal depots contained more extensively replicating clones. Although there were large interanimal differences in clonal composition, variation between animals was always in the same direction for both depots. Clonal composition was unaffected by undernutrition while with animal growth the frequency of the most extensively replicating clones was reduced. Differentiation of precursors occurred in all clones, while differentiation did not occur in skin fibroblasts cloned under identical conditions. Clonal composition and mature fat cell number were related in that fat cell numbers were identical bilaterally in both depots and increased more extensively with growth in perirenal than epididymal tissue. We conclude (a) that clonal composition of adipocyte precursor populations is regulated genetically and by age, (b) that this composition determines, at least in part, the capacity for adipose depot growth.

Wang, H; Kirkland, J L; Hollenberg, C H

1989-01-01

353

The 193 call center, a meaningful public service!  

PubMed

This article is the first part of an on-going ergonomic work analysis with the emergency services call center set up by the Fire Department of the Military Police of São Paulo. The final objective of the research is to identify the prescribed task, the real work executed and strategies used by workers to meet the demands of the job. Starting by identifying the tasks and activities developed, this article analyzes the work of the emergency services call center which is of vital importance to the organizational structure, since it is the start point for the process that results in fulfilling the corporation's mission. PMID:22316697

Eickhoff, Maud; Sznelwar, Laerte Idal

2012-01-01

354

An Intelligent Call Admission Control Decision Mechanism for Wireless Networks  

Microsoft Academic Search

The Call admission control (CAC) is one of the Radio Resource Management\\u000a(RRM) techniques plays instrumental role in ensuring the desired Quality of\\u000aService (QoS) to the users working on different applications which have\\u000adiversified nature of QoS requirements. This paper proposes a fuzzy neural\\u000aapproach for call admission control in a multi class traffic based Next\\u000aGeneration Wireless Networks

S. Ramesh Babu H; Gowrishankar; Satyanarayana P. S

2010-01-01

355

Host-Based Data Exfiltration Detection via System Call Sequences  

SciTech Connect

The host-based detection of malicious data exfiltration activities is currently a sparse area of research and mostly limited to methods that analyze network traffic or signature based detection methods that target specific processes. In this paper we explore an alternative method to host-based detection that exploits sequences of system calls and new collection methods that allow us to catch these activities in real time. We show that system calls sequences can be found to reach a steady state across processes and users, and explore the viability of new methods as heuristics for profiling user behaviors.

Beaver, Justin M [ORNL; Jewell, Brian C [ORNL

2011-01-01

356

High-Level Synthesis of Software Function Calls  

NASA Astrophysics Data System (ADS)

This letter presents a novel framework in high-level synthesis where hardware modules synthesized from functions in a given ANSI-C program can call the other software functions in the program. This enables high-level synthesis from C programs that contains calls to hard-to-synthesize functions, such as dynamic memory management, I/O request, or very large and complex functions. A single-thread implementation scheme is shown, whose correctness has been verified through register transfer level simulation.

Nishimura, Masanari; Ishiura, Nagisa; Ishimori, Yoshiyuki; Kanbara, Hiroyuki; Tomiyama, Hiroyuki

357

Male Prisoners and HIV Prevention: A Call for Action Ignored  

PubMed Central

US prison inmates are disproportionately indigent young men of color. These individuals are severely affected by HIV/AIDS, largely owing to the high-risk behavior that they engage in prior to incarceration. Researchers and practitioners have issued a call for the importance of offering HIV prevention services in prison settings. However, this call has largely been ignored. In this article, we outline reasons why these recommendations have been largely ignored, discuss innovative HIV prevention programs that are currently being implemented in prison settings, and offer recommendations for securing support for HIV prevention services in correctional settings.

Braithwaite, Ronald L.; Arriola, Kimberly R. J.

2008-01-01

358

Nonlinear mesomechanics of composites with periodic microstructure  

NASA Technical Reports Server (NTRS)

This work is concerned with modeling the mechanical deformation or constitutive behavior of composites comprised of a periodic microstructure under small displacement conditions at elevated temperature. A mesomechanics approach is adopted which relates the microimechanical behavior of the heterogeneous composite with its in-service macroscopic behavior. Two different methods, one based on a Fourier series approach and the other on a Green's function approach, are used in modeling the micromechanical behavior of the composite material. Although the constitutive formulations are based on a micromechanical approach, it should be stressed that the resulting equations are volume averaged to produce overall effective constitutive relations which relate the bulk, volume averaged, stress increment to the bulk, volume averaged, strain increment. As such, they are macromodels which can be used directly in nonlinear finite element programs such as MARC, ANSYS and ABAQUS or in boundary element programs such as BEST3D. In developing the volume averaged or efective macromodels from the micromechanical models, both approaches will require the evaluation of volume integrals containing the spatially varying strain distributions throughout the composite material. By assuming that the strain distributions are spatially constant within each constituent phase-or within a given subvolume within each constituent phase-of the composite material, the volume integrals can be obtained in closed form. This simplified micromodel can then be volume averaged to obtain an effective macromodel suitable for use in the MARC, ANSYS and ABAQUS nonlinear finite element programs via user constitutive subroutines such as HYPELA and CMUSER. This effective macromodel can be used in a nonlinear finite element structural analysis to obtain the strain-temperature history at those points in the structure where thermomechanical cracking and damage are expected to occur, the so called damage critical points of the structure.

Walker, Kevin P.; Jordan, Eric H.; Freed, Alan D.

1989-01-01

359

Varying seizure semiology according to age.  

PubMed

The clinical manifestations of seizures change in a predictable fashion with advancing age. For focal seizures these changes can be summarized into domains similar to those used in developmental models. These include fine motor, communication, and gross motor manifestations. Instead of socialization the fourth domain for seizure semiology concerns synchronization. Focal seizures in the very young tend to be simpler with fewer fine motor manifestations. Auras are uncommon, even in young children with some linguistic skill and it is often difficult to discern alteration of consciousness. Infantile focal seizures can present with spasms or even diffuse tonic seizures. In terms of synchronization, orderly secondary generalization is rarely seen so that primary generalized clonic seizures are rarely recorded in infants. Amongst so-called "generalized" seizures spasms are most often seen in the first year of life. Absence seizures, myoclonic-astatic and generalized tonic-clonic seizures are all usually not seen until after age 2 years. A full description of the clinical details of seizures is probably the most important part of the epilepsy history. A detailed knowledge of seizure semiology can make the history more effective and also in the identification of the correct seizure classification. PMID:23622194

Nordli, Douglas R

2013-01-01

360

Novel Microstructures for Polymer-Liquid Crystal Composite Materials  

NASA Technical Reports Server (NTRS)

There are a number of interface-dominated composite materials that contain a liquid crystalline (LC) phase in intimate contact with an isotropic phase. For example, polymer- dispersed liquid crystals, used in the fabrication of windows with switchable transparency, consist of micron size LC droplets dispersed in an isotropic polymer matrix. Many other types of liquid crystal composite materials can be envisioned that might have outstanding optical properties that could be exploited in novel chemical sensors, optical switches, and computer displays. This research project was based on the premise that many of these potentially useful LC composite materials can only be fabricated under microgravity conditions where gravity driven flows are absent. In the ground-based research described below, we have focused on a new class of LC composites that we call thermotropic- lyotropic liquid crystal systems (TLLCs). TLLCs consist of nanosize droplets of water dispersed in an LC matrix, with surfactants at the interface that stabilize the structure. By varying the type of surfactant one can access almost an infinite variety of unusual LC composite microstructures. Due to the importance of the interface in these types of systems, we have also developed molecular simulation models for liquid crystals at interfaces, and made some of the first measurements of the interfacial tension between liquid crystals and water.

Magda, Jules J.

2004-01-01

361

Comparison of somatic mutation calling methods in amplicon and whole exome sequence data  

PubMed Central

Background High-throughput sequencing is rapidly becoming common practice in clinical diagnosis and cancer research. Many algorithms have been developed for somatic single nucleotide variant (SNV) detection in matched tumor-normal DNA sequencing. Although numerous studies have compared the performance of various algorithms on exome data, there has not yet been a systematic evaluation using PCR-enriched amplicon data with a range of variant allele fractions. The recently developed gold standard variant set for the reference individual NA12878 by the NIST-led “Genome in a Bottle” Consortium (NIST-GIAB) provides a good resource to evaluate admixtures with various SNV fractions. Results Using the NIST-GIAB gold standard, we compared the performance of five popular somatic SNV calling algorithms (GATK UnifiedGenotyper followed by simple subtraction, MuTect, Strelka, SomaticSniper and VarScan2) for matched tumor-normal amplicon and exome sequencing data. Conclusions We demonstrated that the five commonly used somatic SNV calling methods are applicable to both targeted amplicon and exome sequencing data. However, the sensitivities of these methods vary based on the allelic fraction of the mutation in the tumor sample. Our analysis can assist researchers in choosing a somatic SNV calling method suitable for their specific needs.

2014-01-01

362

CIT in Context: The Impact of Mental Health Resource Availability and District Saturation on Call Dispositions  

PubMed Central

The goals of Crisis Intervention Team (CIT) programs include improving safety during encounters between police and persons with mental illnesses, diverting persons with mental illnesses away from the criminal justice system, and increasing referral and access to mental health services. CIT is a systemic intervention, and as such, its implementation and effectiveness are influenced by existing practices and infrastructures. However, little research has considered the context in which CIT programs are implemented. In this paper, we present research on CIT in four Chicago police districts that vary in terms of two contextual factors hypothesized to influence the impact of CIT training on how calls involving persons with mental illnesses are resolved. Using data from 112 patrol officers in four Chicago police districts, we consider the impact of mental health services availability and CIT saturation (the percentage of district personnel that are CIT certified). Findings indicate that CIT training increased direction to mental health services primarily in districts with greater availability of mental health services. In districts with low service availability, higher CIT saturation increased direction to mental services. The opposite pattern emerged for contact only or informal call resolution. No effects were found for arrest as a call outcome.

Watson, Amy C; Ottati, Victor C.; Draine, Jeff; Morabito, Melissa

2011-01-01

363

Varied line-space gratings: past, present and future  

SciTech Connect

A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs.

Hettrick, M.C.

1985-08-01

364

Ensemble Control of Finite-Dimensional Time-Varying Linear Systems  

Microsoft Academic Search

In this article, we investigate the problem of simultaneously steering an\\u000auncountable family of finite dimensional time-varying linear systems. We call\\u000athis class of control problems Ensemble Control, a notion coming from the study\\u000aof spin dynamics in Nuclear Magnetic Resonance (NMR) spectroscopy and imaging\\u000a(MRI). This subject involves controlling a continuum of parameterized dynamical\\u000asystems with the same open-loop

Jr-Shin Li

2011-01-01

365

Probabilistic Tangent Subspace Method for M-QAM Signal Equalization in Time-Varying Multipath Channels  

Microsoft Academic Search

\\u000a A new machine learning method called probabilistic tangent subspace is introduced to improve the performance of the equalization\\u000a for the M-QAM modulation signals in wireless communication systems. Due to the mobility of communicator, wireless communication\\u000a channels are time variant. The uncertainties in the time-varying channel’s coefficients cause the amplitude distortion as\\u000a well as the phase distortion of the M-QAM modulation

Jing Yang; Yunpeng Xu; Hongxing Zou

2005-01-01

366

Water permeability of engineered cementitious composites  

Microsoft Academic Search

The water permeability of a unique class of high performance fiber reinforced cementitious composites (HPFRCC) called engineered cementitious composites (ECC) is investigated. These composites are deliberately tailored using microcmechanical design principles to exhibit pseudo-strain-hardening characteristics in uniaxial tension, up to greater than 4% strain. While undergoing tensile deformation, microcracks are designed to saturate the specimen rather than localize into large

Michael D. Lepech; Victor C. Li

2009-01-01

367

Magnetic composite electroplating for depositing micromagnets  

Microsoft Academic Search

This paper reports a novel magnetic composite materials deposition technique called magnetic composite electroplating (MCE). Thin films and micromagnets arrays of a composite matrix consisting of magnetic particles and a ferromagnetic alloy have been fabricated based on this technique. In a typical MCE process, magnetic particles are electrochemically and mechanically embedded into electroplated ferromagnetic thin films to form a magnetic

Shan Guan; Bradley J. Nelson

2006-01-01

368

Social Learning: Medical Student Perceptions of Geriatric House Calls  

ERIC Educational Resources Information Center

Bandura's social learning theory provides a useful conceptual framework to understand medical students' perceptions of a house calls experience at Virginia Commonwealth University School of Medicine. Social learning and role modeling reflect Liaison Committee on Medical Education guidelines for "Medical schools (to) ensure that the learning…

Abbey, Linda; Willett, Rita; Selby-Penczak, Rachel; McKnight, Roberta

2010-01-01

369

Mother goats do not forget their kids' calls  

PubMed Central

Parent–offspring recognition is crucial for offspring survival. At long distances, this recognition is mainly based on vocalizations. Because of maturation-related changes to the structure of vocalizations, parents have to learn successive call versions produced by their offspring throughout ontogeny in order to maintain recognition. However, because of the difficulties involved in following the same individuals over years, it is not clear how long this vocal memory persists. Here, we investigated long-term vocal recognition in goats. We tested responses of mothers to their kids’ calls 7–13 months after weaning. We then compared mothers’ responses to calls of their previous kids with their responses to the same calls at five weeks postpartum. Subjects tended to respond more to their own kids at five weeks postpartum than 11–17 months later, but displayed stronger responses to their previous kids than to familiar kids from other females. Acoustic analyses showed that it is unlikely that mothers were responding to their previous kids simply because they confounded them with the new kids they were currently nursing. Therefore, our results provide evidence for strong, long-term vocal memory capacity in goats. The persistence of offspring vocal recognition beyond weaning could have important roles in kin social relationships and inbreeding avoidance.

Briefer, Elodie F.; Padilla de la Torre, Monica; McElligott, Alan G.

2012-01-01

370

Educational Leadership and Social Activism: A Call for Action  

ERIC Educational Resources Information Center

The purpose of this article is to argue for a social activist stance in educational leadership that fundamentally addresses social change and human emancipation. This call for social activism is framed within neoliberal, neoconservative, and authoritarian populist discourses in the USA, which to social justice educators and leaders had devastating…

Hoffman, Lauren P.

2009-01-01

371

A Call for Cooperative Pluralism from Me to We.  

ERIC Educational Resources Information Center

This collection of training materials describes an educational philosophy for elementary level instruction called cooperative pluralism. This approach complements and strengthens traditional multicultural educational approaches while blending them with cooperative learning and democratic education. The following materials are included: (1) brief…

Nakagawa, Mako

372

Measurement, Analysis and Modeling of RTOS System Calls Timing  

Microsoft Academic Search

This paper presents a methodology for accurately char- acterizing the system calls of an operating system for em- bedded applications. Characterization consists of two phases: measurements and modeling. Measurements al- low a coarse-grained quantitative comparison of differ- ent operating systems. Models, on the other hand, have been derived to gain a more detailed view of the behav- ior of a

Carlo Brandolese; William Fornaciari

2008-01-01

373

CAC-RD: A Call Admission Control for UMTS Networks  

Microsoft Academic Search

This work proposes CAC-RD: a call admission control for UMTS (universal mobile terrestrial system) networks. Its main challenge is to guaranty the maximum access\\/network availability while maintaining satisfactory performance levels. It is based on two schemes: channel reservation and network diagnosis. It reserves dynamically some channels to handovers, based on the network behavior. The diagnosis monitors the network utilization giving

Carlos R. Storck; Anna Izabel T. Ribeiro; Fatima De L. P. Duarte-figueiredo

2008-01-01

374

Physical Activity Promotion in Call Centres: Employers' Perspectives  

ERIC Educational Resources Information Center

This study followed a predominantly qualitative approach to explore the perspectives of employers in Sudbury, Ontario, Canada, call centres (CCs) regarding physical activity (PA) promotion in workplaces, by identifying current practices and employers' motivation to promote PA, as well as perceived facilitators and barriers. In-depth interviews…

Renton, Sheila J.; Lightfoot, Nancy E.; Maar, Marion A.

2011-01-01

375

Teaching Children How and When to Make Emergency Telephone Calls.  

ERIC Educational Resources Information Center

This paper reports to two experiments designed to develop a behavioral procedure to teach young children emergency dialing skills. Experiment 1 evaluated the effects of a behavioral procedure administered by the classroom teachers. In the classrooms training focused upon making phone calls in emergency situations. Six steps in emergency dialing…

Jones, Russell T.; Kazdin, Alan E.

376

Call admission control issues in a wireless ATM network  

Microsoft Academic Search

This paper presents call admission control issues for an ATM-based wireless network with mobile hosts. Such wireless ATM networks are motivated by both an increasing demand for mobile capability for future broadband networks and broadband multimedia services for mobile systems. An ATM compatible wireless network capable of supporting a mix of broadband ISDN services is discussed. We present a conceptual

Lily Cheng; Herman D. Hughes

1995-01-01

377

Joint Call Admission Control for Next Generation Wireless Network  

Microsoft Academic Search

Next generation wireless network (NGWN) will be heterogeneous in nature where different radio access technologies (RATs) such as UMTS, WiMax, WLAN, etc, coexist. This coexistence necessitates joint radio resource management (JRRM). This paper focuses on joint call admission control (JCAC) for NGWN. Factors that determine a user's preference for a particular RAT are discussed. We propose a JCAC algorithm which

Olabisi Emmanuel Falowo; H. Anthony Chan

2006-01-01

378

A New Call Admission Control Scheme for Heterogeneous Wireless Networks  

Microsoft Academic Search

Call Admission Control (CAC) between heterogeneous networks, such as an integrated 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) network and a Wireless Local Area Network (WLAN), plays an important role to utilize the system resources in a more efficient way. In this paper, we propose that the preference to the WLAN is determined based on the traffic load

Duk Kyung Kim; David W. Griffith; Nada Golmie

2010-01-01

379

Call Admission Control for Heterogeneous Services in Wireless Networks  

Microsoft Academic Search

A distributed call admission control (CAC) scheme for heterogeneous services is proposed. The scheme is based on a non-preemptive priority polling scheme and takes advantages of statistically multiplexing user mobility information. It is shown that the scheme can achieve both high resource utilization and low handoff dropping probability

Dongmei Zhao; Xuemin Shen; Jon W. Mark

2000-01-01

380

An adaptive algorithm for call admission control in wireless networks  

Microsoft Academic Search

In the present paper, we develop an adaptive algorithm for call admission control in wireless networks. The algorithm is built upon the concept of guard channels and it uses an adaptation algorithm to search automatically the optimal number of guard channels to be reserved at each base station. The quality of service parameters used in our study are the new

Yi Zhang; Derong Liu

2001-01-01

381

A Call for Student Involvement in the Push for Assessment  

ERIC Educational Resources Information Center

As readers of "Assessment Update" know, the call for assessment is sweeping over the globe, so much so that faculty and administrators are finding it difficult to ignore it--though many may wish they could. Unfortunately, awareness does not lead to an increase in assessment implementation because fear of assessment is still widespread. The push…

Rodgers, Megan

2011-01-01

382

DATA EXTRACTION SYSTEM (DES) / SURVEYS-ON-CALL  

EPA Science Inventory

New name: Surveys-On-Call The Data Extraction System is a tool for extracting records and fields from very large, public-information, data files (for example: survey and census records.) The system produces custom extracts in selectable data file formats (not meant for humans to ...

383

A Call for Change: Providing Solutions for Black Male Achievement  

ERIC Educational Resources Information Center

In October 2010, the Council of the Great City Schools released a major report on the academic status of African American males, "A Call for Change: The Social and Educational Factors Contributing to the Outcomes of Black Males in Urban Schools." The report was the first phase of the Council's efforts to recommit the energies of the nation's urban…

Casserly, Michael; Lewis, Sharon; Simon, Candace; Uzzell, Renata; Palacios, Moses

2012-01-01

384

Towards Model-Driven End-User Development in CALL  

ERIC Educational Resources Information Center

The purpose of this article is to introduce end-user development (EUD) processes to the CALL software development community. EUD refers to the active participation of end-users, as non-professional developers, in the software development life cycle. Unlike formal software engineering approaches, the focus in EUD on means/ends development is…

Farmer, Rod; Gruba, Paul

2006-01-01

385

Nest predation and the evolution of nestling begging calls  

PubMed Central

Begging by nestling birds can be conspicuous and loud. Such displays are thought to function in signalling nestling condition and securing parental care, but they also may inadvertently attract the attention of predators. We compared the structure of nestling begging calls to the risk of predation among 24 species of birds breeding in a forest community in central Arizona. After controlling for body size and phylogeny, we found that species subject to greater nest predation had calls with higher frequency (pitch) and lower amplitude (loudness) than species subject to lower rates of nest predation. As these acoustic features make it difficult for potential predators to pinpoint the source of a sound, our results suggest that an increased risk of predation has led to the evolution of begging calls that minimize locatability. The relationship between call structure and the risk of predation also supports the hypothesis that attracting predators is a direct cost of begging and that such costs can constrain any evolutionary escalation in the intensity of nestling begging.

Briskie, J. V.; Martin, P. R.; Martin, T. E.

1999-01-01

386

Telephone Counseling for Smoking Cessation: What's in a Call?  

ERIC Educational Resources Information Center

Describes a telephone counseling intervention for smoking cessation, with attention to the clinical issues of client assessment, motivation, self-efficacy, planning, coping, relapse-sensitive call scheduling, and self-image. Outlines counselor training and supervision issues, ethical and legal considerations regarding this form of service…

Zhu, Shu-Hong; And Others

1996-01-01

387

Eyes wide shut? Querying the depth of call centre learning  

Microsoft Academic Search

Call centres are high-pressure work environments characterised by routinisation, scripting, computer-based monitoring and intensive performance targets. This promises a series of business advantages, but also risks counterproductive outcomes. Drawing on evidence from ethnographic field data, it is suggested that both desired and risked outcomes are mediated by personal modes of coping and organisational sustaining mechanisms. A central concern is to

Maeve Houlihan

2000-01-01

388

An automated device for provoking and capturing wildlife calls  

USGS Publications Warehouse

Some animals exhibit call-and-response behaviors that can be exploited to facilitate detection. Traditionally, acoustic surveys that use call-and-respond techniques have required an observer's presence to perform the broadcast, record the response, or both events. This can be labor-intensive and may influence animal behavior and, thus, survey results. We developed an automated acoustic survey device using commercially available hardware (e.g., laptop computer, speaker, microphone) and an author-created (JS) software program ("HOOT") that can be used to survey for any animal that calls. We tested this device to determine 1) deployment longevity, 2) effective sampling area, and 3) ability to detect known packs of gray wolves (Canis lupus) in Idaho, USA. Our device was able to broadcast and record twice daily for 6–7 days using the internal computer battery and surveyed an area of 3.3–17.5 km2 in relatively open habitat depending on the hardware components used. We surveyed for wolves at 2 active rendezvous sites used by closely monitored, radiocollared wolf packs and obtained 4 responses across both packs over 3 days of sampling. We confirmed reproduction in these 2 packs by detecting pup howls aurally from the resulting device recordings. Our device can broadcast and record animal calls and the computer software is freely downloadable. This automated survey device can be used to collect reliable data while reducing the labor costs traditionally associated with acoustic surveys.

Ausband, David E.; Skrivseth, Jesse; Mitchell, Michael S.

2011-01-01

389

Campbell's monkeys concatenate vocalizations into context-specific call sequences  

PubMed Central

Primate vocal behavior is often considered irrelevant in modeling human language evolution, mainly because of the caller's limited vocal control and apparent lack of intentional signaling. Here, we present the results of a long-term study on Campbell's monkeys, which has revealed an unrivaled degree of vocal complexity. Adult males produced six different loud call types, which they combined into various sequences in highly context-specific ways. We found stereotyped sequences that were strongly associated with cohesion and travel, falling trees, neighboring groups, nonpredatory animals, unspecific predatory threat, and specific predator classes. Within the responses to predators, we found that crowned eagles triggered four and leopards three different sequences, depending on how the caller learned about their presence. Callers followed a number of principles when concatenating sequences, such as nonrandom transition probabilities of call types, addition of specific calls into an existing sequence to form a different one, or recombination of two sequences to form a third one. We conclude that these primates have overcome some of the constraints of limited vocal control by combinatorial organization. As the different sequences were so tightly linked to specific external events, the Campbell's monkey call system may be the most complex example of ‘proto-syntax’ in animal communication known to date.

Ouattara, Karim; Lemasson, Alban; Zuberbuhler, Klaus

2009-01-01

390

Fast static analysis of C++ virtual function calls  

Microsoft Academic Search

Virtual functions make code easier for programmers to reuse but also make it harder for compilers to analyze. We investigate the ability of three static analysis algorithms to improve C++ programs by resolving virtual function calls, thereby reducing compiled code size and reducing program complexity so as to improve both human and automated program understanding and analysis. In measurements of

David F. Bacon; Peter F. Sweeney

1996-01-01

391

The direct cost of virtual function calls in C++  

Microsoft Academic Search

We study the direct cost of virtual function calls in C++ programs, assuming the standard implementation using virtual function tables. We measure this overhead experimentally for a number of large benchmark programs, using a combination of executable inspection and processor simulation. Our results show that the C++ programs measured spend a median of 5.2% of their time and 3.7% of

Karel Driesen; Urs Hijlzle

1996-01-01

392

1. ABANDONED TURNOUT (CALLED CAPTAIN WHEEL) TO SAN TAN INDIAN ...  

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

1. ABANDONED TURN-OUT (CALLED CAPTAIN WHEEL) TO SAN TAN INDIAN CANAL OFF OF SAN TAN FLOOD-WATER CANAL, T4S, R6E, S11/12. VIEW LOOKING SOUTHWEST. - San Carlos Irrigation Project, San Tan Indian Canal, North of Gila River, Coolidge, Pinal County, AZ

393

Grammar Drills: What CALL Can and Cannot Do.  

ERIC Educational Resources Information Center

The contributions and limitations of computer technology in the presentation of grammar drills, particularly in a second language, are examined by comparing and contrasting the new technology with traditional textbook instruction. It is noted that, in many ways, computer-assisted language learning (CALL) is a derivative form of traditional…

McCarthy, Brian

394

Semi-automated logging of contact center telephone calls  

Microsoft Academic Search

Modern businesses use contact centers as a communication channel with users of their products and services. The largest factor in the expense of running a telephone contact center is the labor cost of its agents. IBM Research has built a new system, Contact-Center Agent Buddies (CAB), which is designed to help reduce the average handle time (AHT) for customer calls,

Roy J. Byrd; Mary S. Neff; Wilfried Teiken; Keh-shin F. Cheng; Stephen C. Gates; Karthik Visweswariah

2008-01-01

395

Timing matters: sonar call groups facilitate target localization in bats.  

PubMed

To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably or unpredictably, under different experimental conditions. We studied the adaptive control of vocal-motor behaviors in free-flying big brown bats, Eptesicus fuscus, as they captured tethered and free-flying insects, in open and cluttered environments. We also studied adaptive sonar behavior in bats trained to track moving targets from a resting position. In each of these experiments, bats adjusted the features of their calls to separate target and clutter. Under many task conditions, flying bats produced prominent sonar sound groups identified as clusters of echolocation pulses with relatively stable intervals, surrounded by longer pulse intervals. In experiments where bats tracked approaching targets from a resting position, bats also produced sonar sound groups, and the prevalence of these sonar sound groups increased when motion of the target was unpredictable. We hypothesize that sonar sound groups produced during flight, and the sonar call doublets produced by a bat tracking a target from a resting position, help the animal resolve dynamic target location and represent the echo scene in greater detail. Collectively, our data reveal adaptive temporal control over sonar call production that allows the bat to negotiate a complex and dynamic environment. PMID:24860509

Kothari, Ninad B; Wohlgemuth, Melville J; Hulgard, Katrine; Surlykke, Annemarie; Moss, Cynthia F

2014-01-01

396

Social calls predict foraging success in big brown bats.  

PubMed

Animals foraging in the dark are engaged simultaneously in prey pursuit, collision avoidance, and interactions with conspecifics, making efficient nonvisual communication essential. A variety of birds and mammals emit food-associated calls that inform, attract, or repel conspecifics (e.g.,). Big brown bats (Eptesicus fuscus) are insectivorous aerial hawkers that may forage near conspecifics and are known to emit social calls (e.g.,). Calls recorded in a foraging setting might attract (e.g.,) or repel conspecifics and could denote territoriality or food claiming. Here, we provide evidence that the "frequency-modulated bout" (FMB), a social call emitted only by male bats (exclusively in a foraging context), is used to claim food and is individually distinct. Bats were studied individually and in pairs in a flight room equipped with synchronized high-speed stereo video and audio recording equipment while sex and experience with a foraging task were experimentally manipulated. Male bats emitting the FMB showed greater success in capturing prey. Following FMB emission, interbat distance, diverging flight, and the other bat's distance to the prey each increased. These findings highlight the importance and utility of vocal communication for a nocturnal animal mediating interactions with conspecifics in a fast-paced foraging setting. PMID:24684936

Wright, Genevieve Spanjer; Chiu, Chen; Xian, Wei; Wilkinson, Gerald S; Moss, Cynthia F

2014-04-14

397

Behavior Modification Project: Reducing and Controlling Calling Out Behaviors.  

ERIC Educational Resources Information Center

The purpose of this study was to determine which behavior modification procedures were the most effective in reducing and controlling the inappropriate calling out behavior of a fifth-grade socially and emotionally disturbed student. Three phases of interventions were involved. As the study began, the resource room instructor was using a behavior…

James, Deborah Anne

398

Toward an Ecological CALL: Update to Garrett (1991)  

ERIC Educational Resources Information Center

This introduction to the 2009 "Modern Language Journal" Focus Issue uses the lens of an ecological perspective on the acquisition of second languages to provide additional insights into the contributions by various computer-assisted language learning (CALL) scholars to this update on Garrett (1991), "Technology in the service of language learning:…

Lafford, Barbara A.

2009-01-01

399

Hurtful Words; Addressing Name Calling at School and Home.  

ERIC Educational Resources Information Center

By understanding why children engage in name calling and responding thoughtfully to such events, parents and teachers can help both the name caller and the victim to grow in their abilities to understand themselves and others. In their own social interactions, children mirror the negative evaluations they have observed. Left unchecked, such…

Byrnes, Deborah A.

400

Calling-song function in male haglids (Orthoptera: Haglidae, Cyphoderris )  

Microsoft Academic Search

We studied the response of males to the singing of nearby male conspecifics in two species of the orthopteran genus Cyphoderris, primitive relatives of crickets and katydids. Lone male Cyphoderris buckelli stridulating in a large cage made a phonotactic approach to a nearby speaker broadcasting conspecific calling song. But in field experiments no phonotaxis to song broadcasts occurred; rather, a

Glenn K. Morris; Paul A. DeLuca; Matthew Norton; Andrew C. Mason

2002-01-01

401

States Mull Obama's Call to Raise Compulsory-Attendance Age  

ERIC Educational Resources Information Center

President Barack Obama's call for every state to require school attendance until age 18 may spark a flurry of action in some statehouses, but changing attendance laws will do little by itself to drive down the nation's dropout rates, experts on the issue say. In his State of the Union address last month, President Obama said states should require…

Maxwell, Lesli A.

2012-01-01

402

New-Media Scholarship: A Call for Research.  

ERIC Educational Resources Information Center

Calls for better research on how information technologies alter graduate education. Proposes questions: (1) "Are our graduate programs preparing students for new media literacies?"; (2) "How can information technology tools facilitate research and writing processes?"; (3) "What training do students need?"; (4) "How can we advance the campus…

Moxley, Joseph M.

2001-01-01

403

Empirical regularities of opening call auction in Chinese stock market  

NASA Astrophysics Data System (ADS)

We study the statistical regularities of an opening call auction using the ultra-high-frequency data of 22 liquid stocks traded on the Shenzhen Stock Exchange in 2003. The distribution of the relative price, defined as the relative difference between the order price in the opening call auction and the closing price on the last trading day, is asymmetric and that the distribution displays a sharp peak at the zero relative price and a relatively wide peak at the negative relative price. The detrended fluctuation analysis (DFA) method is adopted to investigate the long-term memory of relative order prices. We further study the statistical regularities of order sizes in the opening call auction, and observe a phenomenon of number preference, known as order size clustering. The probability density function (PDF) of order sizes could be well fitted by a q-Gamma function, and the long-term memory also exists in order sizes. In addition, both the average volume and the average number of orders decrease exponentially with the price level away from the best bid or ask price level in the limit-order book (LOB) established immediately after the opening call auction, and a price clustering phenomenon is observed.

Gu, Gao-Feng; Ren, Fei; Ni, Xiao-Hui; Chen, Wei; Zhou, Wei-Xing

2010-01-01

404

Business process modelling, simulation and reengineering: call centres  

Microsoft Academic Search

Purpose – The purpose of this paper is to develop a flexible framework through which business processes can be modelled, simulated and reengineered in a cost-effective way. Design\\/methodology\\/approach – This paper is mainly based on a review of the literature and the methodology is discussed in the context of a typical call centre business. Findings – Reengineering business processes involve

Razvi Doomun; Nevin Vunka Jungum

2008-01-01

405

The Heart of Higher Education: A Call to Renewal  

ERIC Educational Resources Information Center

From Parker Palmer, best-selling author of "The Courage to Teach", and Arthur Zajonc, professor of physics at Amherst College and director of the academic program of the Center for Contemplative Mind in Society, comes this call to revisit the roots and reclaim the vision of higher education. "The Heart of Higher Education" proposes an approach to…

Palmer, Parker J.; Zajonc, Arthur

2010-01-01

406

The application of knowledge management in call centres  

Microsoft Academic Search

Purpose – The paper proposes to evaluate the need for knowledge management in a call centre for improving quality of customer services, by addressing the issues specifically relating to information and knowledge management. Design\\/methodology\\/approach – Methodology adopted in this research is qualitative, namely ethnography. After examining six models from literature review, a knowledge management model is developed for implementation to

S. C. L. Koh; A. Gunasekaran; A. Thomas; S. Arunachalam

2005-01-01

407

Dream Catchers: "Margin Call," "Boss," and Climbing the Beanstalk  

ERIC Educational Resources Information Center

Two recent popular entertainments, "Margin Call" (Barnum, Dodson, Jenckes, Moosa, Quinto & Chandor, 2011) and "Boss" (Safinia, 2011), depict powerful and successful groups of bosses confronting sudden, extreme threats. They are forced to react quickly and sacrifice important values to achieve survival of their organizations. In these emergencies,…

Beck, Bernard

2012-01-01

408

Timing matters: sonar call groups facilitate target localization in bats  

PubMed Central

To successfully negotiate a cluttered environment, an echolocating bat must control the timing of motor behaviors in response to dynamic sensory information. Here we detail the big brown bat's adaptive temporal control over sonar call production for tracking prey, moving predictably or unpredictably, under different experimental conditions. We studied the adaptive control of vocal-motor behaviors in free-flying big brown bats, Eptesicus fuscus, as they captured tethered and free-flying insects, in open and cluttered environments. We also studied adaptive sonar behavior in bats trained to track moving targets from a resting position. In each of these experiments, bats adjusted the features of their calls to separate target and clutter. Under many task conditions, flying bats produced prominent sonar sound groups identified as clusters of echolocation pulses with relatively stable intervals, surrounded by longer pulse intervals. In experiments where bats tracked approaching targets from a resting position, bats also produced sonar sound groups, and the prevalence of these sonar sound groups increased when motion of the target was unpredictable. We hypothesize that sonar sound groups produced during flight, and the sonar call doublets produced by a bat tracking a target from a resting position, help the animal resolve dynamic target location and represent the echo scene in greater detail. Collectively, our data reveal adaptive temporal control over sonar call production that allows the bat to negotiate a complex and dynamic environment.

Kothari, Ninad B.; Wohlgemuth, Melville J.; Hulgard, Katrine; Surlykke, Annemarie; Moss, Cynthia F.

2014-01-01

409

12. CLOSEUP OF THE CURRENT TRASH RAKELIFTING MECHANISM (CALLED 'JAWS' ...  

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

12. CLOSE-UP OF THE CURRENT TRASH RAKE-LIFTING MECHANISM (CALLED 'JAWS' BY THE PRESENT OPERATORS), LOOKING WEST. THIS EQUIPMENT WAS REMOVED IN AUTUMN OF 1996. - Washington Water Power Company Post Falls Power Plant, Middle Channel Powerhouse & Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

410

Energy-aware complexity adaptation for mobile video calls  

Microsoft Academic Search

High energy consumption has become a challenge for multimedia applications on mobile platforms. We propose a cross layer framework that integrates complexity adaptation and energy conservation for mobile video calls. First we select the most utility-aware encoding and decoding parameters for videos of different motion levels through extensive offline profiling and analysis. Then we design a feedback algorithm to adaptively

Haiyang Ma; Deepak Gangadharan; Nalini Venkatasubramanian; Roger Zimmermann

2011-01-01

411

Memristive biosensors under varying humidity conditions.  

PubMed

We attempt to examine the potential of silicon nanowire memristors in the field of nanobiosensing. The memristive devices are crystalline Silicon (Si) Nanowires (NWs) with Nickel Silicide (NiSi) terminals. The nanowires are fabricated on a Silicon-on-Insulator (SOI) wafer by an Ebeam Lithography Technique (EBL) process that allows high resolution at the nanoscale. A Deep Reactive Ion Etching (DRIE) technique is used to define free-standing nanowires. The close alignment between Silicon (Si) and Nickel-Silicide (NiSi) terminals forms a Schottky-barrier at their junction. The memristive effect of the fabricated devices matches well with the memristor theory. An equivalent circuit reproducing the memristive effect in current-voltage (I-V) characteristics of our silicon nanowires is presented too. The memristive silicon nanowire devices are then functionalized with anti-human VEGF (Vascular Endothelial Growth Factor) antibody and I-V characteristics are examined for the nanowires prior to and after protein functionalization. The uptake of bio-molecules linked to the surface of the memristive NWs is confirmed by the increased voltage gap in the hysteresis curve. The effects of varying humidity conditions on the conductivity of bio-modified memristive silicon nanowires are deeply investigated. PMID:24594511

Puppo, Francesca; Dave, Akshat; Doucey, Marie-Agnès; Sacchetto, Davide; Baj-Rossi, Camilla; Leblebici, Yusuf; De Micheli, Giovanni; Carrara, Sandro

2014-03-01

412

Serotonin release varies with brain tryptophan levels  

NASA Technical Reports Server (NTRS)

This study examines directly the effects on serotonin release of varying brain tryptophan levels within the physiologic range. It also addresses possible interactions between tryptophan availability and the frequency of membrane depolarization in controlling serotonin release. We demonstrate that reducing tryptophan levels in rat hypothalamic slices (by superfusing them with medium supplemented with 100 microM leucine) decreases tissue serotonin levels as well as both the spontaneous and the electrically-evoked serotonin release. Conversely, elevating tissue tryptophan levels (by superfusing slices with medium supplemented with 2 microM tryptophan) increases both the tissue serotonin levels and the serotonin release. Serotonin release was found to be affected independently by the tryptophan availability and the frequency of electrical field-stimulation (1-5 Hz), since increasing both variables produced nearly additive increases in release. These observations demonstrate for the first time that both precursor-dependent elevations and reductions in brain serotonin levels produce proportionate changes in serotonin release, and that the magnitude of the tryptophan effect is unrelated to neuronal firing frequency. The data support the hypothesis that serotonin release is proportionate to intracellular serotonin levels.

Schaechter, Judith D.; Wurtman, Richard J.

1990-01-01

413

Dermatophyte susceptibility varies towards antimicrobial textiles.  

PubMed

Dermatophytoses are a widespread problem worldwide. Textiles in contact with infected skin can serve as a carrier for fungus propagation. Hitherto, it is unknown, whether antifungal textiles could contribute in controlling dermatophytes e.g. by disrupting the chain of infection. Testing of antimicrobial fabrics for their antifungal activities therefore is a fundamental prerequisite to assess the putative clinical relevance of textiles for dermatophyte prevention. Fabrics finished with either didecyldimethylammonium chloride (DDAC), poly-hexamethylenbiguanide, copper and two silver chloride concentrations were tested for their antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes and Candida albicans. To prove dermatophyte susceptibility towards the textiles, swatches were subjected to DIN EN 14199 (Trichophyton sp.) or DIN EN ISO 20743 (C.?albicans) respectively. In addition, samples were embedded, and semi-thin sections were analysed microscopically. While all samples showed a clear inhibition of C.?albicans, activity against Trichophyton sp. varied significantly: For example, DDAC completely inhibited T.?rubrum growth, whereas T.?mentagrophytes growth remained unaffected even in direct contact to the fibres. The results favour to add T.?mentagrophytes as a test organism in textile dermatophyte efficacy tests. Microscopic analysis of swatches allowed detailed evaluation of additional parameters like mycelium thickness, density and hyphae penetration depth into the fabric. PMID:21914005

Hammer, Timo R; Mucha, Helmut; Hoefer, Dirk

2012-07-01

414

Time-varying modeling of cerebral hemodynamics.  

PubMed

The scientific and clinical importance of cerebral hemodynamics has generated considerable interest in their quantitative understanding via computational modeling. In particular, two aspects of cerebral hemodynamics, cerebral flow autoregulation (CFA) and CO2 vasomotor reactivity (CVR), have attracted much attention because they are implicated in many important clinical conditions and pathologies (orthostatic intolerance, syncope, hypertension, stroke, vascular dementia, mild cognitive impairment, Alzheimer's disease, and other neurodegenerative diseases with cerebrovascular components). Both CFA and CVR are dynamic physiological processes by which cerebral blood flow is regulated in response to fluctuations in cerebral perfusion pressure and blood CO2 tension. Several modeling studies to date have analyzed beat-to-beat hemodynamic data in order to advance our quantitative understanding of CFA-CVR dynamics. A confounding factor in these studies is the fact that the dynamics of the CFA-CVR processes appear to vary with time (i.e., changes in cerebrovascular characteristics) due to neural, endocrine, and metabolic effects. This paper seeks to address this issue by tracking the changes in linear time-invariant models obtained from short successive segments of data from ten healthy human subjects. The results suggest that systemic variations exist but have stationary statistics and, therefore, the use of time-invariant modeling yields "time-averaged models" of physiological and clinical utility. PMID:24184697

Marmarelis, Vasilis Z; Shin, Dae C; Orme, Melissa; Rong Zhang

2014-03-01

415

Varying Collimation for Dark-Field Extraction  

PubMed Central

Although x-ray imaging is widely used in biomedical applications, biological soft tissues have small density changes, leading to low contrast resolution for attenuation-based x-ray imaging. Over the past years, x-ray small-angle scattering was studied as a new contrast mechanism to enhance subtle structural variation within the soft tissue. In this paper, we present a detection method to extract this type of x-ray scattering data, which are also referred to as dark-field signals. The key idea is to acquire an x-ray projection multiple times with varying collimation before an x-ray detector array. The projection data acquired with a collimator of a sufficiently high collimation aspect ratio contain mainly the primary beam with little scattering, while the data acquired with an appropriately reduced collimation aspect ratio include both the primary beam and small-angle scattering signals. Then, analysis of these corresponding datasets will produce desirable dark-field signals; for example, via digitally subtraction. In the numerical experiments, the feasibility of our dark-field detection technology is demonstrated in Monte Carlo simulation. The results show that the acquired dark field signals can clearly reveal the structural information of tissues in terms of Rayleigh scattering characteristics.

Wang, Ge; Cong, Wenxiang; Shen, Haiou; Zou, Yu

2009-01-01

416

Vector curvaton with varying kinetic function  

SciTech Connect

A new model realization of the vector curvaton paradigm is presented and analyzed. The model consists of a single massive Abelian vector field, with a Maxwell-type kinetic term. By assuming that the kinetic function and the mass of the vector field are appropriately varying during inflation, it is shown that a scale-invariant spectrum of superhorizon perturbations can be generated. These perturbations can contribute to the curvature perturbation of the Universe. If the vector field remains light at the end of inflation it is found that it can generate substantial statistical anisotropy in the spectrum and bispectrum of the curvature perturbation. In this case the non-Gaussianity in the curvature perturbation is predominantly anisotropic, which will be a testable prediction in the near future. If, on the other hand, the vector field is heavy at the end of inflation then it is demonstrated that particle production is approximately isotropic and the vector field alone can give rise to the curvature perturbation, without directly involving any fundamental scalar field. The parameter space for both possibilities is shown to be substantial. Finally, toy models are presented which show that the desired variation of the mass and kinetic function of the vector field can be realistically obtained, without unnatural tunings, in the context of supergravity or superstrings.

Dimopoulos, Konstantinos; Karciauskas, Mindaugas; Wagstaff, Jacques M. [Physics Department, Lancaster University, Lancaster LA1 4YB (United Kingdom)

2010-01-15

417

Filtration behavior of slurries with varying compressibilities  

SciTech Connect

A novel filtration apparatus allows simultaneous measurements of filtrate volume, hydraulic pressure and cake thickness using slurry volumes on the order of 100 cm/sup 3/. Differences in interparticle interactions were studied by varying the barium chloride concentration of 0.38-..mu..m polystyrene latex and filtering at pressures between 2 and 100 psi. Cakes formed from these slurries are highly compressible for concentrations between 0.01M and 0.10M, moderately compressible for the 0.005M concentration, and incompressible for the 0.001M concentration. Plots of filtrate volume versus cake thickness were linear for the incompressible cakes, whereas the compressible cakes showed significant deviations, which were pressure dependent. The pressure distribution for the incompressible cake was found to be essentially linear as predicted from the resistance plots assuming constant ..cap alpha.. and epsilon. For the highly compressible cakes, most of the pressure drop appears to occur near the cake/medium interface with only small changes occurring at the top of the cake.

Massuda, M.; Bridger, K.; Harvey, M.; Tiller, F.M.

1988-10-01

418

General dynamics of varying-alpha universes  

NASA Astrophysics Data System (ADS)

We introduce and study extensions of the varying alpha theory of Bekenstein-Sandvik-Barrow-Magueijo to allow for an arbitrary coupling function and self-interaction potential term in the theory. We study the full evolution equations without assuming that variations in alpha have a negligible effect on the expansion scale factor and the matter density evolution, as was assumed in earlier studies. The background Friedmann-Robertson-Walker cosmology of this model in the cases of zero and nonzero spatial curvature is studied in detail, using dynamical systems techniques, for a wide class of potentials and coupling functions. All the asymptotic behaviors are found, together with some new solutions. We study the cases where the electromagnetic parameter, zeta, is positive and negative, corresponding to magnetic and electrostatic energy domination in the nonrelativistic matter. In particular, we investigate the cases where the scalar field driving alpha variations has exponential and power-law self-interaction potentials and the behavior of theories where the coupling constant between matter and alpha variations is no longer a constant.

Barrow, John D.; Graham, Alexander A. H.

2013-11-01

419

Time-Varying Modeling of Cerebral Hemodynamics  

PubMed Central

The scientific and clinical importance of cerebral hemodynamics has generated considerable interest in their quantitative understanding via computational modeling. In particular, two aspects of cerebral hemodynamics, Cerebral Flow Autoregulation (CFA) and CO2 Vasomotor Reactivity (CVR), have attracted much attention because they are implicated in many important clinical conditions and pathologies (orthostatic intolerance, syncope, hypertension, stroke, vascular dementia, MCI, Alzheimer’s disease and other neurodegenerative diseases with cerebrovascular components). Both CFA and CVR are dynamic physiological processes by which cerebral blood flow is regulated in response to fluctuations in cerebral perfusion pressure and blood CO2 tension. Several modeling studies to date have analyzed beat-to-beat hemodynamic data in order to advance our quantitative understanding of CFA-CVR dynamics. A confounding factor in these studies is the fact that the dynamics of the CFA-CVR processes appear to vary with time (i.e. changes in cerebrovascular characteristics) due to neural, endocrine and metabolic effects. This paper seeks to address this issue by tracking the changes in linear time-invariant models obtained from short successive segments of data from 10 healthy human subjects. The results suggest that systemic variations exist but have stationary statistics and, therefore, the use of time-invariant modeling yields “time-averaged models” of physiological and clinical utility.

Marmarelis, Vasilis Z.; Shin, Dae C.; Orme, Melissa; Zhang, Rong

2014-01-01

420

Secure, web-accessible call rosters for academic radiology departments.  

PubMed

Traditionally, radiology department call rosters have been posted via paper and bulletin boards. Frequently, changes to these lists are made by multiple people independently, but often not synchronized, resulting in confusion among the house staff and technical staff as to who is on call and when. In addition, multiple and disparate copies exist in different sections of the department, and changes made would not be propagated to all the schedules. To eliminate such difficulties, a paperless call scheduling application was developed. Our call scheduling program allowed Java-enabled web access to a database by designated personnel from each radiology section who have privileges to make the necessary changes. Once a person made a change, everyone accessing the database would see the modification. This eliminates the chaos resulting from people swapping shifts at the last minute and not having the time to record or broadcast the change. Furthermore, all changes to the database were logged. Users are given a log-in name and password and can only edit their section; however, all personnel have access to all sections' schedules. Our applet was written in Java 2 using the latest technology in database access. We access our Interbase database through the DataExpress and DB Swing (Borland, Scotts Valley, CA) components. The result is secure access to the call rosters via the web. There are many advantages to the web-enabled access, mainly the ability for people to make changes and have the changes recorded and propagated in a single virtual location and available to all who need to know. PMID:10847414

Nguyen, A V; Tellis, W M; Avrin, D E

2000-05-01

421

Corrosion behavior of squeeze-cast-aluminum metal-matrix composites. Final report  

SciTech Connect

Corrosion behavior of metal matrix composites (MMC) vary greatly with the reinforcement material type, processing conditions and methods of fabrication into engineering parts. The corrosion susceptibilities for the MMC arise from the segregations of the reinforcement material during fluid flow (extrusion) and/or processing, and from the resulting compositional differences in the alloy, the matrix material. These differences sets-up galvanic cells and cause preferential corrosion. The metal matrix composites studied were Al 6061/Al2O3 and Al 356/SiC. In particular, the effects of near-net-shape processing called squeeze casting (solidification of liquid under pressure) was investigated. The results showed that regions which were clustered with SiC or (Al203)Oi were microstructurally sensitive to preferential corrosion. Electrochemical-potentiodynamic polarization and controlled potential corrosion behavior measurements were made and related to microstructural segregation through metallographic optical microscopic analysis.

Agarwala, V.S.; Fabiszewski, A.S.

1991-12-01

422

Metastable solidification of composites  

NASA Astrophysics Data System (ADS)

Current efforts in modern materials development and materials design are directed towards improving the physical and chemical properties of advanced materials and the efficiency in casting and materials solidification processing. Considerable interest is focused on producing new materials that combine the different properties of various phases and substances within one solid piece of matter. These materials are known as composites and are the subject of this MAP project. Two groups of composites are considered. First, multiphase materials consist of at least two different phases of varying properties; they can be produced as in situ composites via peritectic solidification routes. Second, two-material composites, which contain both metallic elements as a matrix with particles of ceramics dispersed homogeneously so that the different properties of a metal (such as ductility) and a ceramic (such as high yield strength) are combined within one material. Earth's gravity imposes severe restrictions on the production of such composites from the liquid state.

Kolbe, Matthias; Eggeler, Gunther; Gránásy, László; Herlach, Dieter M.; Ludwig, Andreas; Rappaz, Michel; Duursma, René; Jestrabek, Jürgen; Charbon, Christian; Sellger, Roland; Kuhn, Hans-Achim

2005-10-01

423

Neonatal Intensive Care Unit Safety Culture Varies Widely  

PubMed Central

background Variation in health care delivery and outcomes in NICUs may be partly explained by differences in safety culture. objective To describe NICU caregiver assessments of safety culture, explore the variability within and between NICUs on safety culture domains, and test for association with caregiver characteristics. methods We surveyed NICU caregivers in a convenience sample of 12 hospitals from a single health care system, using the Safety Attitudes Questionnaire (SAQ). The six scales of the SAQ include teamwork climate, safety climate, job satisfaction, stress recognition, perception of management, and working conditions. For each NICU we calculated scale means, standard deviations and percent positives (percent agreement). results We found substantial variation in safety culture domains among participating NICUs. A composite mean score across the six safety culture domains ranged from 56.3 to 77.8 on a 100-point scale and NICUs in the top four NICUs were significantly different from the bottom four (p < .001). Across the six domains, respondent assessments varied widely, but were least positive on perceptions of management (3–80% positive; mean 33.3%) and stress recognition (18–61% positive; mean 41.3%). Comparisons of SAQ scale scores between NICUs and a previously published cohort of adult ICUs generally revealed higher scores for NICUs. Physicians composite scores were 8.2 (p = .04) and 9.5 (p =.02) points higher than nurses and ancillary personnel. conclusion Significant variation and scope for improvement in safety culture exists among this sample of NICUs. The NICU variation was similar to variation in adult ICUs, but NICU scores were generally higher than adult ICU scores. Future studies should validate whether safety culture as measured with the SAQ correlates with clinical and operational outcomes in the NICU setting.

Profit, Jochen; Etchegaray, Jason; Petersen, Laura A; Sexton, J Bryan; Hysong, Sylvia J; Mei, Minghua; Thomas, Eric J

2013-01-01

424

Vocal corollary discharge communicates call duration to vertebrate auditory system.  

PubMed

Corollary discharge is essential to an animal's ability to filter self-generated from external stimuli. This includes acoustic communication, although direct demonstration of a corollary discharge that both conveys a vocal motor signal and informs the auditory system about the physical attributes of a self-generated vocalization has remained elusive for vertebrates. Here, we show the underlying synaptic activity of a neuronal vocal corollary discharge pathway in the hindbrain of a highly vocal species of fish. Neurons carrying the vocal corollary discharge are specifically adapted for the transmission of duration information, a predominant acoustic cue. The results reveal that vertebrates, like some insects, have a robust corollary discharge conveying call duration. Along with evidence for the influence of vocal duration on auditory encoding in mammals, these new findings suggest that linking vocal motor and corollary discharge pathways with pattern generating, call duration neurons is a shared network character across the animal kingdom. PMID:24285884

Chagnaud, Boris P; Bass, Andrew H

2013-11-27

425

Subclonal variant calling with multiple samples and prior knowledge  

PubMed Central

Motivation: Targeted resequencing of cancer genes in large cohorts of patients is important to understand the biological and clinical consequences of mutations. Cancers are often clonally heterogeneous, and the detection of subclonal mutations is important from a diagnostic point of view, but presents strong statistical challenges. Results: Here we present a novel statistical approach for calling mutations from large cohorts of deeply resequenced cancer genes. These data allow for precisely estimating local error profiles and enable detecting mutations with high sensitivity and specificity. Our probabilistic method incorporates knowledge about the distribution of variants in terms of a prior probability. We show that our algorithm has a high accuracy of calling cancer mutations and demonstrate that the detected clonal and subclonal variants have important prognostic consequences. Availability: Code is available as part of the Bioconductor package deepSNV. Contact: mg14@sanger.ac.uk; pc8@sanger.ac.uk

Gerstung, Moritz; Papaemmanuil, Elli; Campbell, Peter J.

2014-01-01

426

A Reference Based Analysis Framework for Analyzing System Call Traces  

SciTech Connect

Reference based analysis (RBA) is a novel data mining tool for exploring a test data set with respect to a reference data set. The power of RBA lies in it ability to transform any complex data type, such as symbolic sequences and multi-variate categorical data instances, into a multivariate continuous representation. The transformed representation not only allows visualization of the complex data, which cannot be otherwise visualized in its original form, but also allows enhanced anomaly detection in the transformed feature space. We demonstrate the application of the RBA framework in analyzing system call traces and show how the transformation results in improved intrusion detection performance over state of art data mining based intrusion detection methods developed for system call traces.

Chandola, Varun [ORNL; Kumar, Vipin [University of Minnesota; Boriah, Shyam [University of Minnesota

2010-01-01

427

Somatic Point Mutation Calling in Low Cellularity Tumors  

PubMed Central

Somatic mutation calling from next-generation sequencing data remains a challenge due to the difficulties of distinguishing true somatic events from artifacts arising from PCR, sequencing errors or mis-mapping. Tumor cellularity or purity, sub-clonality and copy number changes also confound the identification of true somatic events against a background of germline variants. We have developed a heuristic strategy and software (http://www.qcmg.org/bioinformatics/qsnp/) for somatic mutation calling in samples with low tumor content and we show the superior sensitivity and precision of our approach using a previously sequenced cell line, a series of tumor/normal admixtures, and 3,253 putative somatic SNVs verified on an orthogonal platform.

Kassahn, Karin S.; Holmes, Oliver; Nones, Katia; Patch, Ann-Marie; Miller, David K.; Christ, Angelika N.; Harliwong, Ivon; Bruxner, Timothy J.; Xu, Qinying; Anderson, Matthew; Wood, Scott; Leonard, Conrad; Taylor, Darrin; Newell, Felicity; Song, Sarah; Idrisoglu, Senel; Nourse, Craig; Nourbakhsh, Ehsan; Manning, Suzanne; Wani, Shivangi; Steptoe, Anita; Pajic, Marina; Cowley, Mark J.; Pinese, Mark; Chang, David K.; Gill, Anthony J.; Johns, Amber L.; Wu, Jianmin; Wilson, Peter J.; Fink, Lynn; Biankin, Andrew V.; Waddell, Nicola; Grimmond, Sean M.; Pearson, John V.

2013-01-01

428

Vocal Corollary Discharge Communicates Call Duration to Vertebrate Auditory System  

PubMed Central

Corollary discharge is essential to an animal's ability to filter self-generated from external stimuli. This includes acoustic communication, although direct demonstration of a corollary discharge that both conveys a vocal motor signal and informs the auditory system about the physical attributes of a self-generated vocalization has remained elusive for vertebrates. Here, we show the underlying synaptic activity of a neuronal vocal corollary discharge pathway in the hindbrain of a highly vocal species of fish. Neurons carrying the vocal corollary discharge are specifically adapted for the transmission of duration information, a predominant acoustic cue. The results reveal that vertebrates, like some insects, have a robust corollary discharge conveying call duration. Along with evidence for the influence of vocal duration on auditory encoding in mammals, these new findings suggest that linking vocal motor and corollary discharge pathways with pattern generating, call duration neurons is a shared network character across the animal kingdom.

2013-01-01

429

Five benefits of call recording for medical practices.  

PubMed

Despite documentation's essential positioning in medical practices of all sizes and specialties, one aspect of patient and insurance provider interaction remains overlooked in the majority of practices: telephone-based communication. In many cases, patient and payment information exchanged via telephone is logged with little more than a note typed or written in the patient file. This leads to "he said/she said" disagreements with regard to patient service, consultations, and coding; reduced payments from insurance providers; incomplete patient records; liability exposure; and a host of other problems. In this article, call recording professional Roland Murphy explains how a call recording solution can fill the gaps in documentation, increase practice revenues, and improve patient care without excessive investment costs and while protecting patient confidentiality. PMID:20480782

Murphy, Roland

2010-01-01

430

Call-graph-based inter-class MM path generation  

NASA Astrophysics Data System (ADS)

Inter-class testing is the testing of classes for composing an object-oriented system or subsystem during integration. MM Path is defined as an interleaved sequence of method executions linked by messages. It represents the interactions between methods in object-oriented software well, hence fits for object-oriented integration testing. However, the current MM Path generation methods only support intra-class testing. In this paper, a call-graph-based approach is proposed to promote MM Path automatic generation from intra-class to inter-class level. The approach is evaluated by controlled experiments on 12 Java benchmark programs with two typical call graph construction algorithms, Class Hierarchy Analysis and Anderson's Points-to Analysis. Then, the impact of the two algorithms on inter-class MM path generation efficiency is studied. The result shows that our approach is practicable and Anderson's Points-to Analysis outperforms Class Hierarchy Analysis for inter-class MM Path generation.

He, Wei; Zhao, Ruilian

2011-12-01

431

Call admission control for time-dependent video connections  

NASA Astrophysics Data System (ADS)

Call admission control (CAC) of time-dependent video connections is an important issue for network traffic engineering. The impact of this traffic dependence on video call acceptance region is examined in this article. We considered two different CAC mechanisms; (1) a descriptor- based CAC mechanism and (2) a measurement-based CAC (MBCAC) mechanism. The proposed MBCAC is a hybrid measurement scheme that includes a Kalman filter and a real-time Hurst estimation. We investigated several buffer sizes and video sequences with different dependence degrees. For the accuracy of the Hurst estimation, we developed a Hurst parameter package. The package consists of three different estimators, R/S, Higuchi and Abry-Veitch (wavelet). An important result shows that long-range dependence and short- range dependence connections have similar admission regions.

Pontes, Raniery; Coelho, Rosangela

2001-02-01

432

Viewers: A Data-World Analogue of Procedure Calls  

Microsoft Academic Search

A viewer is a reference-valued datum with a special meaning: a value of the data pointed by the viewer be- comes a virtual part of data where the viewer is placed; the value virtually substit.utes the viewer. Viewers are considered to be a dat,a-world analogue of procedure calls. They possess a large conceptual and pragmatic potential as a result of

Kazimierz Subieta; Florian Matthes; Joachim W. Schmidt; Andreas Rudloff

1993-01-01

433

Call Admission Control in Wireless Networks over Rayleigh Fading Channel  

Microsoft Academic Search

Call admission control (CAC) is a significant component in wireless networks to guarantee quality-of-service (QoS) requirements and also to enhance the network resilience. In the literature, CAC is normally evaluated by considering the limited bandwidth in the radio interface while the physical fading wireless channel is not considered. This work proposes a cross-layer analytical technique to study a CAC mechanism

Yan Zhang

2007-01-01

434

Intelligent call admission control using fuzzy logic in wireless networks  

Microsoft Academic Search

Scarcity of the spectrum resource and mobility of users make quality-of-service (QoS) provision a critical issue in wireless networks. This paper presents a fuzzy call admission control scheme to meet the requirement of the QoS. It searches automatically the optimal number of the guard channels in a base station to make an effective use of resource and guarantee the QoS

Yufeng Ma; Xiulin Hu; Yunyu Zhang; Yimei Shi

2005-01-01

435

Cosmology with Time-Varying G  

NASA Astrophysics Data System (ADS)

It is shown that a Universe with a time-varying gravitational “constant” G necessarily implies creation if the rest mass of matter particles m p is constant. In this case, from Einstein's field equations, the conditions for energy-momentum propagation are ? ·( GT ? v ) from which matter and photon propagation equations are derived. Free matter particle propagation is not affected by creation that is given by GN pmp=const, where N p is the number of matter particles within a proper volume. This relation introduces explicitly the rest mass of the Universe into the field equations. Free photon propagation is affected by creation that is given by GT ? v R=const, where N ? is the number of photons within a proper volume, which is the cosmic red shift law. Conservation of the cosmic background photon distribution determines photon creation as G 3 N {?/4}. The results are applied to the case G ? t -1 equivalent to N p ÷ t. It is found that at an age t=1, 0-40 t o, of the order light takes to travel a proton size, Planck's units become of the order of the proton's mass m p, size r p, and time r p/c. Hence, matter particles at this age are quantum black holes. Evaporation of these quantum black holes at this age gives a background blackbody radiation that, red shifted to present time t 0, gives the present cosmic microwave background. A cosmological model of the Friedmann type is constructed. The red shift versus distance relation is derived taking into account creation. Using a Hubble's constant H obs=50 km sec-1 Mpc-1 and a deceleration parameter q obs=1.0 the model is of the type k=1 and gives a present age t 0=6.81×109 yr, consistent with Uranium model ages. Thus, the three results for the age of the Universe, i.e., radioactive decay, Hubble's constant, and stellar evolution are brought together in this creation model. The matter-dominated era occurs for t>7.6×10-3 t 0, while the radiation-dominated era occurs for 7.6×10-3 t o> t>10-40 t o. The origin of the Universe is placed at this last limit, which is Planck's time at the corresponding G, consisting of quantum black holes at a temperature Ti?=3×1011K.

Alfonso-Faus, Antonio

1986-03-01

436

Adoption Activities on the Internet: A Call for Regulation  

ERIC Educational Resources Information Center

There is a growing practice of adoption services on the Internet with varying degrees of regulation, depending on whether it is domestic infant adoption, public foster care adoption, or international adoption. Regulation is particularly lacking in domestic infant adoptions, with Web sites connecting prospective birth and adoptive parents,…

Roby, Jini L.; White, Holly

2010-01-01

437

Social learning: medical student perceptions of geriatric house calls.  

PubMed

Bandura's social learning theory provides a useful conceptual framework to understand medical students' perceptions of a house calls experience at Virginia Commonwealth University School of Medicine. Social learning and role modeling reflect Liaison Committee on Medical Education guidelines for "Medical schools (to) ensure that the learning environment for medical students promotes the development of explicit and appropriate professional attributes (attitudes, behaviors, and identity) in their medical students." This qualitative study reports findings from open-ended survey questions from 123 medical students who observed a preceptor during house calls to elderly homebound patients. Their comments included reflections on the medical treatment as well as interactions with family and professional care providers. Student insights about the social learning process they experienced during house calls to geriatric patients characterized physician role models as dedicated, compassionate, and communicative. They also described patient care in the home environment as comprehensive, personalized, more relaxed, and comfortable. Student perceptions reflect an appreciation of the richness and complexity of details learned from home visits and social interaction with patients, families, and caregivers. PMID:20509061

Abbey, Linda; Willett, Rita; Selby-Penczak, Rachel; McKnight, Roberta

2010-01-01

438

An Interactional Model of the Call for Survey Participation  

PubMed Central

Previous research has proposed that the actions of sample members may provide encouraging, discouraging, or ambiguous interactional environments for interviewers soliciting participation in surveys. In our interactional model of the recruitment call that brings together the actions of interviewers and sample members, we examine features of actions that may contribute to an encouraging or discouraging environment in the opening moments of the call. Using audio recordings from the 2004 wave of the Wisconsin Longitudinal Study and an innovative design that controls for sample members’ estimated propensity to participate in the survey, we analyze an extensive set of interviewers’ and sample members’ actions, the characteristics of those actions, and their sequential location in the interaction. We also analyze whether a sample member’s subsequent actions (e.g., a question about the length of the interview or a “wh-type” question) constitute an encouraging, discouraging, or ambiguous environment within which the interviewer must produce her next action. Our case-control design allows us to analyze the consequences of actions for the outcome of the call.

Schaeffer, Nora Cate; Garbarski, Dana; Freese, Jeremy; Maynard, Douglas W.

2013-01-01

439

Towards Agent-Oriented Approach to a Call Management System  

NASA Astrophysics Data System (ADS)

There is more chance of a completed sale if the end customers and relationship managers are suitably matched. This in turn can reduce the number of calls made by a call centre reducing operational costs such as working time and phone bills. This chapter is part of ongoing research aimed at helping a CMC to make better use of its personnel and equipment while maximizing the value of the service it offers to its client companies and end customers. This is accomplished by ensuring the optimal use of resources with appropriate real-time scheduling and load balancing and matching the end customers to appropriate relationship managers. In a globalized market, this may mean taking into account the cultural environment of the customer, as well as the appropriate profile and/or skill of the relationship manager to communicate effectively with the end customer. The chapter evaluates the suitability of a MAS to a call management system and illustrates the requirement analysis phase using i* models.

Ashamalla, Amir Nabil; Beydoun, Ghassan; Low, Graham

440

Spatially Varying Spectrally Thresholds for MODIS Cloud Detection  

NASA Technical Reports Server (NTRS)

The EOS science team has developed an elaborate global MODIS cloud detection procedure, and the resulting MODIS product (MOD35) is used in the retrieval process of several geophysical parameters to mask out clouds. While the global application of the cloud detection approach appears quite robust, the product has some shortcomings on the regional scale, often over determining clouds in a variety of settings, particularly at night. This over-determination of clouds can cause a reduction in the spatial coverage of MODIS derived clear-sky products. To minimize this problem, a new regional cloud detection method for use with MODIS data has been developed at NASA's Global Hydrology and Climate Center (GHCC). The approach is similar to that used by the GHCC for GOES data over the continental United States. Several spatially varying thresholds are applied to MODIS spectral data to produce a set of tests for detecting clouds. The thresholds are valid for each MODIS orbital pass, and are derived from 20-day composites of GOES channels with similar wavelengths to MODIS. This paper and accompanying poster will introduce the GHCC MODIS cloud mask, provide some examples, and present some preliminary validation.

Haines, S. L.; Jedlovec, G. J.; Lafontaine, F.

2004-01-01

441

YBa 2Fe 3O 8 with Varied Oxygen Content  

NASA Astrophysics Data System (ADS)

The oxygen content in YBa 2Fe 3O 8+ w is varied within -0.2 < w < 0.1 by thermal equilibration upon controlling the oxygen partial pressure (10 -30 < pO 2 < 150 atm) at various temperatures (950 < T < 1250 K) and by the getter technique. No decomposition is observed at the upper reached oxygen level. The lower oxygen content limit is estimated as 7.75 per formula unit, evidenced by the first sign of one or more Fe 2+ phases appearing before the final degradation into metallic Fe. The unit cell volume has a maximum at the stoichiometric oxygen content (corresponding to Fe III), and the (high-temperature) electrical conductivity shows a minimum close to this composition, which is reached below pO 2 = 10 -12 atm for temperatures below 1250 K. In oxygen-rich atmospheres, the conductivity becomes independent of temperature above some 800 K. Magnetic susceptibility measurements confirm the occurrence of antiferromagnetism in YBa 2Fe 3O 8+ w, with TN ˜ 700 K, and some irregular features are pointed out.

Karen, P.; Kjekshus, A.

1994-09-01

442

DEGRADATION CHARACTERISTICS OF GOLDEN LION TAMARIN LEONTOPITHECUS ROSALIA TWO-PHRASE LONG CALLS: IMPLICATIONS FOR CALL DETECTION AND RANGING IN THE EVERGREEN FOREST  

Microsoft Academic Search

Neotropical primates have evolved long calls, which have a role in spacing and cohesion of groups. Detection and “reading” of long calls as well as ranging of calling individuals seem essential for this role. This study used sound propagation experiments to investigate habitat caused degradation of long calls of the Golden Lion Tamarin Leontopithecus rosalia and its implications for “reading”

VERA SABATINI; CARLOS R. RUIZ-MIRANDA; TORBEN DABELSTEEN

2011-01-01

443

Composite Abortable Locks  

Microsoft Academic Search

The need to allow threads to abort an attempt to ac- quire a lock (sometimes called a timeout) is an interest- ing new requirement driven by state-of-the-art database applications with soft real-time constraints. This paper presents a new composite abortable lock (CAL), a com- bination of abortable queue-based (QL) and test-and- set based backoff (BL) lock mechanisms, which provides non-blocking

Virendra J. Marathe; Mark Moir; Nir Shavit

2006-01-01

444

Stock market context of the Lévy walks with varying velocity  

NASA Astrophysics Data System (ADS)

We developed the most general Lévy walks with varying velocity, shorter called the Weierstrass walks (WW) model, by which one can describe both stationary and non-stationary stochastic time series. We considered a non-Brownian random walk where the walker moves, in general, with a velocity that assumes a different constant value between the successive turning points, i.e., the velocity is a piecewise constant function. This model is a kind of Lévy walks where we assume a hierarchical, self-similar in a stochastic sense, spatio-temporal representation of the main quantities such as waiting-time distribution and sojourn probability density (which are principal quantities in the continuous-time random walk formalism). The WW model makes possible to analyze both the structure of the Hurst exponent and the power-law behavior of kurtosis. This structure results from the hierarchical, spatio-temporal coupling between the walker displacement and the corresponding time of the walks. The analysis uses both the fractional diffusion and the super Burnett coefficients. We constructed the diffusion phase diagram which distinguishes regions occupied by classes of different universality. We study only such classes which are characteristic for stationary situations. We thus have a model ready for describing the data presented, e.g., in the form of moving averages; the operation is often used for stochastic time series, especially financial ones. The model was inspired by properties of financial time series and tested for empirical data extracted from the Warsaw stock exchange since it offers an opportunity to study in an unbiased way several features of stock exchange in its early stage.

Kutner, Ryszard

2002-11-01

445

Thin-Film Metamaterials Called Sculptured Thin Films  

Microsoft Academic Search

\\u000a Morphology and performance are conjointed attributes of metamaterials, of which sculptured thin films (STFs) are examples.\\u000a STFs are assemblies of nanowires that can be fabricated from many different materials, typically via physical vapor deposition\\u000a onto rotating substrates. The curvilinear-nanowire morphology of STFs is determined by the substrate motions during fabrication.\\u000a The optical properties, especially, can be tailored by varying the

Akhlesh Lakhtakia; Joseph B. Geddes III

2010-01-01

446

Effect of outside air ventilation rate on VOC concentrations and emissions in a call center  

SciTech Connect

A study of the relationship between outside air ventilation rate and concentrations of VOCs generated indoors was conducted in a call center. Ventilation rates were manipulated in the building's four air handling units (AHUs). Concentrations of VOCs in the AHU returns were measured on 7 days during a 13-week period. Indoor minus outdoor concentrations and emission factors were calculated. The emission factor data was subjected to principal component analysis to identify groups of co-varying compounds based on source type. One vector represented emissions of solvents from cleaning products. Another vector identified occupant sources. Direct relationships between ventilation rate and concentrations were not observed for most of the abundant VOCs. This result emphasizes the importance of source control measures for limiting VOC concentrations in buildings.

Hodgson, A.T.; Faulkner, D.; Sullivan, D.P.; DiBartolomeo, D.L.; Russell, M.L.; Fisk, W.J.

2002-01-01

447

Mating call recognition in the barking treefrog ( Hyla gratiosa ): Responses to synthetic calls and comparisons with the green treefrog ( Hyla cinerea )  

Microsoft Academic Search

1.Eighty-six of 93 gravid females ofH. gratiosa responded in 471 of 566 two-choice experiments; in most experiments synthetic mating calls were used.2.A synthetic call was as attractive as a typical natural (recorded) call only if it had a distinct pulsatile beginning (Table 1).3.Females preferred a periodic synthetic call (500\\/s) over an aperiodic (filtered noise) call, but failed to show a

H. Carl Gerhardt

1981-01-01

448

Thermal diffusivity measurements on composite porosity samples  

NASA Technical Reports Server (NTRS)

A phase lag technique is used to make quantitative measurements of diffusivity in composite porosity samples. Changes in through-ply diffusivity in a graphite composite due to varying porosity levels are examined. The relationship between the amount of porosity and the change in diffusivity is analyzed using an electrical analog for modeling heat flow in the composite.

Zalameda, Joseph N.; Winfree, William P.

1990-01-01

449

Ambient noise causes independent changes in distinct spectro-temporal features of echolocation calls in horseshoe bats.  

PubMed

One of the most efficient mechanisms to optimize signal-to-noise ratios is the Lombard effect - an involuntary rise in call amplitude due to ambient noise. It is often accompanied by changes in the spectro-temporal composition of calls. We examined the effects of broadband-filtered noise on the spectro-temporal composition of horseshoe bat echolocation calls, which consist of a constant-frequency component and initial and terminal frequency-modulated components. We found that the frequency-modulated components became larger for almost all noise conditions, whereas the bandwidth of the constant-frequency component increased only when broadband-filtered noise was centered on or above the calls' dominant or fundamental frequency. This indicates that ambient noise independently modifies the associated acoustic parameters of the Lombard effect, such as spectro-temporal features, and could significantly affect the bat's ability to detect and locate targets. Our findings may be of significance in evaluating the impact of environmental noise on echolocation behavior in bats. PMID:24855671

Hage, Steffen R; Jiang, Tinglei; Berquist, Sean W; Feng, Jiang; Metzner, Walter

2014-07-15

450

Calling ET or not Even Answering the Phone?  

NASA Astrophysics Data System (ADS)

The complex query (in the Title) can be divided into two more simple questions: To Send or not to Send? ("Calling") and To Answer or not to Answer? ("Answering"). The second question will be vital maybe tomorrow morning (if the SETI-signal was detected) or maybe never. And in any case, such answering requires a careful analysis of any ET-message received. The first question is quite suitable and feasible for analysis right now. There are two `pro' arguments: Asteroid Hazard and Loss of Interest.

Zaitsev, A.

451

Poisoning hospitalization correlates with poison center call frequency  

Microsoft Academic Search

Introduction  Poison Control Centers (PCCs) have been shown to reduce health expenditures by reducing emergency department and clinic visits.\\u000a The effect or association of PCC call frequency on acute hospitalization rates for poisonings has not been studied extensively.\\u000a \\u000a \\u000a \\u000a Methods  All nonfederal hospital discharges for acute poisoning principal diagnosis codes (960–979, 980–989, 9956X, 3030, and 005)\\u000a in California between October 1999 and June

Timothy E. Albertson; R. Steven Tharratt; Kathy Marquardt; Judith Alsop; John K. Ninomiya; Garrett E. Foulke

2008-01-01

452

Experimental Manipulation of the Microbial Functional Amyloid Called Curli  

PubMed Central

Curli are proteinaceous fibrous structures produced on the surface of many gram-negative bacteria. As a major constituent of the extracellular matrix, curli mediate interactions between the bacteria and its environment, and as such, curli play a critical role in bio film formation. Curli fibers share biophysical properties with a growing number of remarkably stable and ordered protein aggregates called amyloid. Here we describe experimental methods to study the biogenesis and assembly of curli by exploiting their amyloid properties. We also present methods to analyze curli-mediated biofilm formation. These approaches are straightforward and can easily be adapted to study other bacterially produced amyloids.

Zhou, Yizhou; Smith, Daniel R.; Hufnagel, David A.; Chapman, Matthew R.

2013-01-01

453

Call sign intelligibility improvement using a spatial auditory display  

NASA Technical Reports Server (NTRS)

A spatial auditory display was used to convolve speech stimuli, consisting of 130 different call signs used in the communications protocol of NASA's John F. Kennedy Space Center, to different virtual auditory positions. An adaptive staircase method was used to determine intelligibility levels of the signal against diotic speech babble, with spatial positions at 30 deg azimuth increments. Non-individualized, minimum-phase approximations of head-related transfer functions were used. The results showed a maximal intelligibility improvement of about 6 dB when the signal was spatialized to 60 deg or 90 deg azimuth positions.

Begault, Durand R.

1993-01-01

454

Multifunctional Self-Healing and Morphing Composites.  

National Technical Information Service (NTIS)

Highly innovative work towards development of a new class of materials called 'Multifunctional Composites (MCs)' for multi-role structural aircraft skin applications possessing both self-healing and morphing functionality has been achieved. Proof of conce...

A. Mal E. Bolanos E. Murphy F. Wudl T. Duenas

2006-01-01

455

Technology Education/Engineering Education: A Call for Collaboration  

NSDL National Science Digital Library

Globally, Colleges of Engineering are placing more and more emphasis on engineering education. The desire to improve engineering pedagogy and the saturation of some fields of engineering is a call for collaboration. Several National Science Foundation "Bridges for Engineering" planning grants have been awarded to provide funding for collaboration to improve engineering faculty's pedagogy and classroom methods. This paper discusses that call for collaboration and suggests that technology education is the group that will provide engineering faculty with innovative practices in teaching. A brief history of collaborations is revealed to convince engineering faculty that technology education is the appropriate vehicle, technology education and engineering education are defined and compared. Literature reviews reveal that technology educators have been teaching engineering concepts for over 100 years. Herein, the need for technology education/engineering education collaboration is discussed. Collaboration initiation and implementation strategies of current K-12, post -secondary, and professional models are presented. National Academy of Engineering president, William A. Wulf, endorses technology education as the vehicle to implement change; therefore, recommendations from the literature are made. Conclusions drawn indicate action is necessary on the part of technology educators and engineering educators alike. Target Audience: 2-4 Year College Faculty/Administrators, High School Faculty/Administrators

Pendleton, Leslie K.; Varnado, Terri E.

2009-11-10

456

[The controversy about so-called "active euthanasia"].  

PubMed

In the past few years, the discussion about the right to kill severely ill patients for humanitarian reasons--once called euthanasia and after World War II in the German speaking countries as euphemism called 'aktive Sterbehilfe' (active help to die)--has become more intensive. Actually, only the Netherlands do officially practice euthanasia. But the variant that consists in putting a pharmaceutical at the patient's disposal in order to kill himself is very well known in other countries, e.g. in Switzerland, where the pressure on the legislator to also legalize euthanasia grows. Taking into account medico-ethical reasons, historical experiences, alarming euthanasia ideas in bioethics and social philosophy, the danger due to the impossibility to control the development in this field, and the insidious extension of euthanasia indications, the author rejects firmly the idea of legalized euthanasia. These problems are related to those that occur in fixing the moment of death of potential organ donors. A lack of organs in transplantation medicine should not lead physicians to explant organs from donors in a dying condition. For physicians who take care of potential organ donors and who have to look after their interests towards transplantation teams, it is often too difficult to cope with this task. Local ethical commissions should support them. PMID:8927895

Karbowski, K

1996-09-17

457

Group calls for space policies to transcend politics  

NASA Astrophysics Data System (ADS)

At a 22 May briefing, the American Institute of Aeronautics and Astronautics (AIAA) called on Congress to “establish space exploration policy goals which transcend partisan political differences.” AIAA president and former NASA administrator Michael Griffin said the “goal of establishing human capability to b e a space-faring species is not a short-term goal,” nor is it a goal that belongs to only one political party. “We will not reach long-term goals without a stable, coherent, sensible plan that transcends elections and leaders,” said Griffin, who has provided advice to Republican U.S. presidential candidate Mitt Romney. Griffin pointed to NASA's 2008 authorization as providing the kind of vision needed for NASA. The act called for human return to the Moon and preparation for the capability for permanent bases on the Moon, among other things, he said. “That's the kind of thing that we need. All of the goals espoused by the 2008 act were long-term, generational, strategic in scope,” Griffin said, adding that the act, which had bipartisan support, demonstrated “the kind of societal support, rather than political support, that I believe our space program deserves.”

Showstack, Randy

2012-06-01