Climate warming may increase aphids' dropping probabilities in response to high temperatures.

PubMed

Ma, Gang; Ma, Chun-Sen

2012-11-01

Dropping off is considered an anti-predator behavior for aphids since previous studies have shown that it reduces the risk of predation. However, little attention is paid to dropping behavior triggered by other external stresses such as daytime high temperatures which are predicted to become more frequent in the context of climate warming. Here we defined a new parameter, drop-off temperature (DOT), to describe the critical temperature at which an aphid drops off its host plant when the ambient temperature increases gradually and slowly. Detailed studies were conducted to reveal effects of short-term acclimation (temperature, exposure time at high-temperature and starvation) on DOT of an aphid species, Sitobion avenae. Our objectives were to test if the aphids dropped off host plant to avoid high temperatures and how short-term acclimation affected the aphids' dropping behavior in response to heat stress. We suggest that dropping is a behavioral thermoregulation to avoid heat stress, since aphids started to move before they dropped off and the dropped aphids were still able to control their muscles prior to knockdown. The adults starved for 12 h had higher DOT values than those that were unstarved or starved for 6 h, and there was a trade-off between behavioral thermoregulation and energy acquisition. Higher temperatures and longer exposure times at high temperatures significantly lowered the aphids' DOT, suggested that the aphids avoid heat stress by dropping when exposed to high temperatures. Climate warming may therefore increase the aphids' dropping probabilities and consequently affect the aphids' individual development and population growth. Copyright © 2012 Elsevier Ltd. All rights reserved.

Enhanced intelligent water drops algorithm for multi-depot vehicle routing problem

PubMed Central

Akutsah, Francis; Olusanya, Micheal O.; Adewumi, Aderemi O.

2018-01-01

The intelligent water drop algorithm is a swarm-based metaheuristic algorithm, inspired by the characteristics of water drops in the river and the environmental changes resulting from the action of the flowing river. Since its appearance as an alternative stochastic optimization method, the algorithm has found applications in solving a wide range of combinatorial and functional optimization problems. This paper presents an improved intelligent water drop algorithm for solving multi-depot vehicle routing problems. A simulated annealing algorithm was introduced into the proposed algorithm as a local search metaheuristic to prevent the intelligent water drop algorithm from getting trapped into local minima and also improve its solution quality. In addition, some of the potential problematic issues associated with using simulated annealing that include high computational runtime and exponential calculation of the probability of acceptance criteria, are investigated. The exponential calculation of the probability of acceptance criteria for the simulated annealing based techniques is computationally expensive. Therefore, in order to maximize the performance of the intelligent water drop algorithm using simulated annealing, a better way of calculating the probability of acceptance criteria is considered. The performance of the proposed hybrid algorithm is evaluated by using 33 standard test problems, with the results obtained compared with the solutions offered by four well-known techniques from the subject literature. Experimental results and statistical tests show that the new method possesses outstanding performance in terms of solution quality and runtime consumed. In addition, the proposed algorithm is suitable for solving large-scale problems. PMID:29554662

Enhanced intelligent water drops algorithm for multi-depot vehicle routing problem.

PubMed

Ezugwu, Absalom E; Akutsah, Francis; Olusanya, Micheal O; Adewumi, Aderemi O

2018-01-01

The intelligent water drop algorithm is a swarm-based metaheuristic algorithm, inspired by the characteristics of water drops in the river and the environmental changes resulting from the action of the flowing river. Since its appearance as an alternative stochastic optimization method, the algorithm has found applications in solving a wide range of combinatorial and functional optimization problems. This paper presents an improved intelligent water drop algorithm for solving multi-depot vehicle routing problems. A simulated annealing algorithm was introduced into the proposed algorithm as a local search metaheuristic to prevent the intelligent water drop algorithm from getting trapped into local minima and also improve its solution quality. In addition, some of the potential problematic issues associated with using simulated annealing that include high computational runtime and exponential calculation of the probability of acceptance criteria, are investigated. The exponential calculation of the probability of acceptance criteria for the simulated annealing based techniques is computationally expensive. Therefore, in order to maximize the performance of the intelligent water drop algorithm using simulated annealing, a better way of calculating the probability of acceptance criteria is considered. The performance of the proposed hybrid algorithm is evaluated by using 33 standard test problems, with the results obtained compared with the solutions offered by four well-known techniques from the subject literature. Experimental results and statistical tests show that the new method possesses outstanding performance in terms of solution quality and runtime consumed. In addition, the proposed algorithm is suitable for solving large-scale problems.

Educational Subculture and Dropping out in Higher Education: A Longitudinal Case Study

ERIC Educational Resources Information Center

Venuleo, C.; Mossi, P.; Salvatore, S.

2016-01-01

The paper tests longitudinally the hypothesis that educational subcultures in terms of which students interpret their role and their educational setting affect the probability of dropping out of higher education. A logistic regression model was performed to predict drop out at the beginning of the second academic year for the 823 freshmen of a…

When Volunteering Is Mandatory: A Call for Research about Service Learning

ERIC Educational Resources Information Center

Cloyd, Melissa

2017-01-01

Stakeholders have long been concerned about high school drop-out rates and associated achievement gaps between groups, specifically racial, of high school students. While significant improvements have been made to these drop-out rates at the national level, the largest group of drop-out students continues to be those of Hispanic heritage. Research…

Risky Business: Reducing Moral Hazard in Airlift Operations

DTIC Science & Technology

2012-06-01

as to use a weather balloon to mark one of Dien Bien Phu’s drop zones in hopes of making drop operations viable when airland operations were not. In...casualties (killed, wounded, missing) of just over 7,000 and probably over 9,000 taken captive at the end of the battle with the odds stacked against...tethered weather balloon to guide their drops when they could not see the drop zone. Using the Ground-Controlled Approach (GCA) radar, personnel

Strategic obstacle placement reduces drop breakup probability in concentrated emulsion flowing into a constriction

NASA Astrophysics Data System (ADS)

Khor, Jian Wei; Hua, Yu; Bick, Alison; Tang, Sindy

2017-11-01

In this study, we investigate the effect of an obstacle on the breakup probability of droplets within a concentrated emulsion flowing into a constriction. We introduce a concentrated emulsion as a 2D monolayer through a tapered channel into a narrow constriction. This geometry is commonly used for the serial interrogation of droplet content in droplet microfluidics applications. We found that certain drop-drop interactions near the constriction entrance lead to the breakup of these drops at a high flow rates. Such breakup sets the upper limit for the droplet interrogation throughput. Incidentally, previous findings have shown that strategic placement of a circular post near a narrow exit can reduce the conflict from the interactions among living organisms (humans, ants, and sheep) or a cluster of particles when entering a narrow exit. Inspired by these results, we modify the tapered channel by placing a circular post in a strategic location near the constriction entrance in order to reduce catastrophic drop-drop interactions and to avoid breakup. Preliminary work shows that the circular posts can reduce the breakup fraction of drops by up to 17%. The optimization of the location and size of the obstacle is expected to further reduce the breakup fraction.

The Effects of High School Organization on Dropping Out: An Exploratory Investigation. CPRE Research Report Series.

ERIC Educational Resources Information Center

Bryk, Anthony S.; Thum, Yeow Meng

Examined in this paper are the effects of school characteristics on both the probability of dropping out and absenteeism as the strongest predictor of dropping out. The project employed a subsample from the High School and Beyond database that contains results from questionnaires and achievement tests given in 1980 to approximately 30,000…

The Failure Models of Lead Free Sn-3.0Ag-0.5Cu Solder Joint Reliability Under Low-G and High-G Drop Impact

NASA Astrophysics Data System (ADS)

Gu, Jian; Lei, YongPing; Lin, Jian; Fu, HanGuang; Wu, Zhongwei

2017-02-01

The reliability of Sn-3.0Ag-0.5Cu (SAC 305) solder joint under a broad level of drop impacts was studied. The failure performance of solder joint, failure probability and failure position were analyzed under two shock test conditions, i.e., 1000 g for 1 ms and 300 g for 2 ms. The stress distribution on the solder joint was calculated by ABAQUS. The results revealed that the dominant reason was the tension due to the difference in stiffness between the print circuit board and ball grid array, and the maximum tension of 121.1 MPa and 31.1 MPa, respectively, under both 1000 g or 300 g drop impact, was focused on the corner of the solder joint which was located in the outmost corner of the solder ball row. The failure modes were summarized into the following four modes: initiation and propagation through the (1) intermetallic compound layer, (2) Ni layer, (3) Cu pad, or (4) Sn-matrix. The outmost corner of the solder ball row had a high failure probability under both 1000 g and 300 g drop impact. The number of failures of solder ball under the 300 g drop impact was higher than that under the 1000 g drop impact. The characteristic drop values for failure were 41 and 15,199, respectively, following the statistics.

Shear coaxial injector atomization phenomena for combusting and non-combusting conditions

NASA Technical Reports Server (NTRS)

Pal, S.; Moser, M. D.; Ryan, H. M.; Foust, M. J.; Santoro, R. J.

1992-01-01

Measurements of LOX drop size and velocity in a uni-element liquid propellant rocket chamber are presented. The use of the Phase Doppler Particle Analyzer in obtaining temporally-averaged probability density functions of drop size in a harsh rocket environment has been demonstrated. Complementary measurements of drop size/velocity for simulants under cold flow conditions are also presented. The drop size/velocity measurements made for combusting and cold flow conditions are compared, and the results indicate that there are significant differences in the two flowfields.

[Optimize dropping process of Ginkgo biloba dropping pills by using design space approach].

PubMed

Shen, Ji-Chen; Wang, Qing-Qing; Chen, An; Pan, Fang-Lai; Gong, Xing-Chu; Qu, Hai-Bin

2017-07-01

In this paper, a design space approach was applied to optimize the dropping process of Ginkgo biloba dropping pills. Firstly, potential critical process parameters and potential process critical quality attributes were determined through literature research and pre-experiments. Secondly, experiments were carried out according to Box-Behnken design. Then the critical process parameters and critical quality attributes were determined based on the experimental results. Thirdly, second-order polynomial models were used to describe the quantitative relationships between critical process parameters and critical quality attributes. Finally, a probability-based design space was calculated and verified. The verification results showed that efficient production of Ginkgo biloba dropping pills can be guaranteed by operating within the design space parameters. The recommended operation ranges for the critical dropping process parameters of Ginkgo biloba dropping pills were as follows: dropping distance of 5.5-6.7 cm, and dropping speed of 59-60 drops per minute, providing a reference for industrial production of Ginkgo biloba dropping pills. Copyright© by the Chinese Pharmaceutical Association.

Modeling evaporation of Jet A, JP-7 and RP-1 drops at 1 to 15 bars

NASA Technical Reports Server (NTRS)

Harstad, K.; Bellan, J.

2003-01-01

A model describing the evaportion of an isolated drop of a multicomponent fuel containing hundreds of species has been developed. The model is based on Continuous Thermodynamics concepts wherein the composition of a fuel is statistically described using a Probability Distribution Function (PDF).

The Effects of High School Organization on Dropping Out: An Exploratory Investigation.

ERIC Educational Resources Information Center

Bryk, Anthony S.; Thum, Yeow Meng

1989-01-01

A hierarchical linear model analysis investigated the effects of structural and normative features of schools on absenteeism and the probability of dropping out. Subjects included 4,450 sophomores in 160 Catholic and public high schools from the High School and Beyond 1980 cohort. (SLD)

Building America Top Innovations 2012: Reduced Call-Backs with High-Performance Production Builders

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

2013-01-01

This Building America Top Innovations profile describes ways Building America teams have helped builders cut call-backs. Harvard University study found builders who worked with Building America had a 50% drop in call-backs. One builder reported a 50-fold reduction in the incidence of pipe freezing, a 50% reduction in drywall cracking, and a 60% decline in call-backs.

Ganges Chasma Landslide

NASA Technical Reports Server (NTRS)

2002-01-01

(Released 01 April 2002) This image shows a spectacular landslide along a portion of the southern wall of Ganges Chasma within Valles Marineris. Landslides have very characteristic morphologies on Earth, which they also display on Mars. These morphologies include a distinctive escarpment at the uppermost part of the landslide--called a head scarp (seen at the bottom of this image), a down-dropped block of material below that escarpment that dropped almost vertically, and a deposit of debris that moved away from the escarpment at high speed. In this example, the wall rock displayed in the upper part of the cliff is layered, with spurs and chutes created by differing amounts of erosion. Below the steep scarp is a smoother, steep slope of material with small, narrow tongues of debris that have eroded off of the escarpment since the landslide occurred (a talus slope). The actual landslide deposit, visible in the upper half of this image, shows striations that form by differences in the side-by-side motion during high velocity emplacement. This immense landslide traveled some 70 km at speeds that probably exceeded 100 kilometers per hour (60 miles per hour) before coming to rest, forming abrupt, terminal fronts (upper right corner of image). Even at these high speeds, this massive landslide was moving for nearly an hour before it came to rest.

The structure of dilute combusting sprays

NASA Technical Reports Server (NTRS)

Shuen, J. S.; Solomon, A. S. P.; Faeth, F. M.

1985-01-01

An experimental and theoretical study of drop processes in a turbulent flame is described. The experiments involved a monodisperse (105 and 180 micro m initial diameter) stream of methanol drops injected at the base of a turbulent methane-fueled diffusion flame burning in still air. The following measurements were made: mean and fluctuating phase velocities, mean drop number flux, drop-size distributions and mean gas-phase temperatures. Measurements were compared with predictions of two separated flow models: (1) deterministic separated flow, where drop-turbulence interactions are ignored; and (2) stochastic separated flow, where drop-turbulence interactions are considered using random-walk computations. The stochastic separated flow analysis yielded best agreement with measurements, since it provides for turbulent dispersion of drops which was important for present test conditions (and probably for most combusting sprays as well). Distinguishing the presence or absence of envelope flames around the drops, however, was relatively unimportant for present test conditions, since the drops spent most of their lifetime in fuel-rich regions of the flow where this distinction is irrelevant.

Spatial Distribution of Large Cloud Drops

NASA Technical Reports Server (NTRS)

Marshak, A.; Knyazikhin, Y.; Larsen, M.; Wiscombe, W.

2004-01-01

By analyzing aircraft measurements of individual drop sizes in clouds, we have shown in a companion paper (Knyazikhin et al., 2004) that the probability of finding a drop of radius r at a linear scale l decreases as l(sup D(r)) where 0 less than or equal to D(r) less than or equal to 1. This paper shows striking examples of the spatial distribution of large cloud drops using models that simulate the observed power laws. In contrast to currently used models that assume homogeneity and therefore a Poisson distribution of cloud drops, these models show strong drop clustering, the more so the larger the drops. The degree of clustering is determined by the observed exponents D(r). The strong clustering of large drops arises naturally from the observed power-law statistics. This clustering has vital consequences for rain physics explaining how rain can form so fast. It also helps explain why remotely sensed cloud drop size is generally biased and why clouds absorb more sunlight than conventional radiative transfer models predict.

Small-Scale Drop-Size Variability: Empirical Models for Drop-Size-Dependent Clustering in Clouds

NASA Technical Reports Server (NTRS)

Marshak, Alexander; Knyazikhin, Yuri; Larsen, Michael L.; Wiscombe, Warren J.

2005-01-01

By analyzing aircraft measurements of individual drop sizes in clouds, it has been shown in a companion paper that the probability of finding a drop of radius r at a linear scale l decreases as l(sup D(r)), where 0 less than or equals D(r) less than or equals 1. This paper shows striking examples of the spatial distribution of large cloud drops using models that simulate the observed power laws. In contrast to currently used models that assume homogeneity and a Poisson distribution of cloud drops, these models illustrate strong drop clustering, especially with larger drops. The degree of clustering is determined by the observed exponents D(r). The strong clustering of large drops arises naturally from the observed power-law statistics. This clustering has vital consequences for rain physics, including how fast rain can form. For radiative transfer theory, clustering of large drops enhances their impact on the cloud optical path. The clustering phenomenon also helps explain why remotely sensed cloud drop size is generally larger than that measured in situ.

DNS of moderate-temperature gaseous mixing layers laden with multicomponent-fuel drops

NASA Technical Reports Server (NTRS)

Clercq, P. C. Le; Bellan, J.

2004-01-01

A formulation representing multicomponent-fuel (MC-fuel) composition as a Probability Distribution Function (PDF) depending on the molar weight is used to construct a model of a large number of MC-fuel drops evaporating in a gas flow, so as to assess the extent of fuel specificity on the vapor composition.

A Computer-Interfaced Drop Counter as an Inexpensive Fraction Collector for Column Chromatography

ERIC Educational Resources Information Center

Nash, Barbara T.

2008-01-01

A computer-interfaced drop counter is described that serves as an inexpensive alternative to a fraction collector for column chromatography experiments. Undergraduate biochemistry laboratories frequently do not have the budget to purchase fraction collectors. Protocols that call for the manual measurement of fraction volumes as well as the manual…

Drop-in Security for Distributed and Portable Computing Elements.

ERIC Educational Resources Information Center

Prevelakis, Vassilis; Keromytis, Angelos

2003-01-01

Proposes the use of a special purpose drop-in firewall/VPN gateway called Sieve, that can be inserted between the mobile workstation and the network to provide individualized security services for that particular station. Discusses features and advantages of the system and demonstrates how Sieve was used in various application areas such as at…

The competitiveness versus the wealth of a country.

PubMed

Podobnik, Boris; Horvatić, Davor; Kenett, Dror Y; Stanley, H Eugene

2012-01-01

Politicians world-wide frequently promise a better life for their citizens. We find that the probability that a country will increase its per capita GDP (gdp) rank within a decade follows an exponential distribution with decay constant λ = 0.12. We use the Corruption Perceptions Index (CPI) and the Global Competitiveness Index (GCI) and find that the distribution of change in CPI (GCI) rank follows exponential functions with approximately the same exponent as λ, suggesting that the dynamics of gdp, CPI, and GCI may share the same origin. Using the GCI, we develop a new measure, which we call relative competitiveness, to evaluate an economy's competitiveness relative to its gdp. For all European and EU countries during the 2008-2011 economic downturn we find that the drop in gdp in more competitve countries relative to gdp was substantially smaller than in relatively less competitive countries, which is valuable information for policymakers.

The competitiveness versus the wealth of a country

PubMed Central

Podobnik, Boris; Horvatić, Davor; Kenett, Dror Y.; Stanley, H. Eugene

2012-01-01

Politicians world-wide frequently promise a better life for their citizens. We find that the probability that a country will increase its per capita GDP (gdp) rank within a decade follows an exponential distribution with decay constant λ = 0.12. We use the Corruption Perceptions Index (CPI) and the Global Competitiveness Index (GCI) and find that the distribution of change in CPI (GCI) rank follows exponential functions with approximately the same exponent as λ, suggesting that the dynamics of gdp, CPI, and GCI may share the same origin. Using the GCI, we develop a new measure, which we call relative competitiveness, to evaluate an economy's competitiveness relative to its gdp. For all European and EU countries during the 2008–2011 economic downturn we find that the drop in gdp in more competitve countries relative to gdp was substantially smaller than in relatively less competitive countries, which is valuable information for policymakers. PMID:22997552

The competitiveness versus the wealth of a country

NASA Astrophysics Data System (ADS)

Podobnik, Boris; Horvatić, Davor; Kenett, Dror Y.; Stanley, H. Eugene

2012-09-01

Politicians world-wide frequently promise a better life for their citizens. We find that the probability that a country will increase its per capita GDP (gdp) rank within a decade follows an exponential distribution with decay constant λ = 0.12. We use the Corruption Perceptions Index (CPI) and the Global Competitiveness Index (GCI) and find that the distribution of change in CPI (GCI) rank follows exponential functions with approximately the same exponent as λ, suggesting that the dynamics of gdp, CPI, and GCI may share the same origin. Using the GCI, we develop a new measure, which we call relative competitiveness, to evaluate an economy's competitiveness relative to its gdp. For all European and EU countries during the 2008-2011 economic downturn we find that the drop in gdp in more competitve countries relative to gdp was substantially smaller than in relatively less competitive countries, which is valuable information for policymakers.

Inverse Leidenfrost effect: self-propelling drops on a bath

NASA Astrophysics Data System (ADS)

Gauthier, Anais; van der Meer, Devaraj; Lohse, Detlef; Physics of Fluids Team

2017-11-01

When deposited on very hot solid, volatile drops can levitate over a cushion of vapor, in the so-called Leidenfrost state. This phenomenon can also be observed on a hot bath and similarly to the solid case, drops are very mobile due to the absence of contact with the substrate that sustains them. We discuss here a situation of ``inverse Leidenfrost effect'' where room-temperature drops levitate on a liquid nitrogen pool - the vapor is generated here by the bath sustaining the relatively hot drop. We show that the drop's movement is not random: the liquid goes across the bath in straight lines, a pattern only disrupted by elastic bouncing on the edges. In addition, the drops are initially self-propelled; first at rest, they accelerate for a few seconds and reach velocities of the order of a few cm/s, before slowing down. We investigate experimentally the parameters that affect their successive acceleration and deceleration, such as the size and nature of the drops and we discuss the origin of this pattern.

Using Single Drop Microextraction for Headspace Analysis with Gas Chromatography

ERIC Educational Resources Information Center

Riccio, Daniel; Wood, Derrick C.; Miller, James M.

2008-01-01

Headspace (HS) gas chromatography (GC) is commonly used to analyze samples that contain non-volatiles. In 1996, a new sampling technique called single drop microextraction, SDME, was introduced, and in 2001 it was applied to HS analysis. It is a simple technique that uses equipment normally found in the undergraduate laboratory, making it ideal…

The Probability of Hitting a Polygonal Target

DTIC Science & Technology

1981-04-01

required for the use of this method for coalputing the probability of hitting d polygonal target. These functions are 1. PHIT (called by user’s main progran...2. FIJ (called by PHIT ) 3. FUN (called by FIJ) The user must include all three of these in his main program, but needs only to call PHIT . The

Respiratory allergy to inhaled bat guano.

PubMed

el-Ansary, E H; Tee, R D; Gordon, D J; Taylor, A J

1987-02-07

In the Sudan many asthmatic patients attribute their symptoms to inhalation of bat droppings. Design of the roofs of many Sudanese buildings allows black bats to roost; guano drops through cracks in the ceiling into the rooms below where it can be inhaled and cause allergic respiratory disorders. Seven atopic patients seen at Sennar Hospital with bat-related case-histories were investigated. Six had bronchial asthma and allergic rhinitis and one had asthma alone. Extracts of yellow hairy bat, black bat, and bat droppings were made. All seven patients had a positive skin prick test and specific IgE antibodies (RAST) to bat droppings. Three patients also had a positive RAST to both yellow and black bats and one patient to yellow bat. Droppings are probably the major allergen source in bat-related respiratory allergy.

Direct Numerical Simulation of Transitional Multicomponent-Species Gaseous and Multicomponent-Liquid Drop-Laden Mixing

NASA Technical Reports Server (NTRS)

Selle, Laurent C.; Bellan, Josette

2006-01-01

A model of multicomponent-liquid (MC-liquid) drop evaporation in a three-dimensional mixing layer is here exercised at larger Reynolds numbers than in a previous study, and transitional states are obtained. The gas phase is followed in an Eulerian frame and the multitude of drops is described in a Lagrangian frame. Complete coupling between phases is included with source terms in the gas conservation equations accounting for the drop/flow interaction in terms of drop drag, drop heating and species evaporation. The liquid composition, initially specified as a single-Gamma (SG) probability distribution function (PDF) depending on the molar mass is allowed to evolve into a linear combination of two SGPDFs, called the double-Gamma PDF (DGPDF). The compositions of liquid and vapor emanating from the drops are calculated through four moments of the DGPDFs, which are drop-specific and location-specific, respectively. The mixing layer is initially excited to promote the double pairing of its four initial spanwise vortices into an ultimate vortex in which small scales proliferate. Simulations are performed for four liquids of different compositions and the effect of the initial mass loading and initial free-stream gas temperature are explored. For reference, Simulations are also performed for gaseous multicomponent mixing layers for which the effect of Reynolds number is investigated. The results encompass examination of the global layer characteristics, flow visualizations and homogeneous-plane statistics at transition. Comparisons are performed with previous pre-transitional MC-liquid simulations and with transitional single-component (SC) liquid studies. It is found that MCC flows at transition, the classical energy cascade is of similar strength, but that the smallest scales contain orders of magnitude less energy than SC flows, which is confirmed by the larger viscous dissipation in the former case. Contrasting to pre-transitional MC flows, the vorticity and drop organization depend on the initial gas temperature, this being due to the drop/turbulence coupling. The vapor-composition mean molar mass and standard deviation distributions strongly correlate with the initial liquid-composition PDF; such a correlation only exists for the magnitude of the mean but not for that of the standard deviation. Unlike in pre-transitional situations, regions of large composition standard deviation no longer necessarily coincide with regions of large mean molar mass. The kinetic energy, rotational and composition characteristics, and dissipation are liquid specific and the variation among liquids is amplified with increasing free-stream gas temperature. Eulerian and Lagrangian statistics of gas-phase quantities show that the different. Observation framework may affect the perception of the flow characteristics. The gas composition, of which the first four moments are calculated, is shown to be close to, but distinct from a SGPDF. The PDF of the scalar dissipation rate is calculated for drop-laden layers and is shown to depart more significantly from the typically assumed Gaussian in gaseous flows than experimentally measured gaseous scalar dissipation rates, this being attributed to the increased heterogeneity due to drop/flow interactions.

Response of the San Andreas fault to the 1983 Coalinga-Nuñez earthquakes: an application of interaction-based probabilities for Parkfield

USGS Publications Warehouse

Toda, Shinji; Stein, Ross S.

2002-01-01

The Parkfield-Cholame section of the San Andreas fault, site of an unfulfilled earthquake forecast in 1985, is the best monitored section of the world's most closely watched fault. In 1983, the M = 6.5 Coalinga and M = 6.0 Nuñez events struck 25 km northeast of Parkfield. Seismicity rates climbed for 18 months along the creeping section of the San Andreas north of Parkfield and dropped for 6 years along the locked section to the south. Right-lateral creep also slowed or reversed from Parkfield south. Here we calculate that the Coalinga sequence increased the shear and Coulomb stress on the creeping section, causing the rate of small shocks to rise until the added stress was shed by additional slip. However, the 1983 events decreased the shear and Coulomb stress on the Parkfield segment, causing surface creep and seismicity rates to drop. We use these observations to cast the likelihood of a Parkfield earthquake into an interaction-based probability, which includes both the renewal of stress following the 1966 Parkfield earthquake and the stress transfer from the 1983 Coalinga events. We calculate that the 1983 shocks dropped the 10-year probability of a M ∼ 6 Parkfield earthquake by 22% (from 54 ± 22% to 42 ± 23%) and that the probability did not recover until about 1991, when seismicity and creep resumed. Our analysis may thus explain why the Parkfield earthquake did not strike in the 1980s, but not why it was absent in the 1990s. We calculate a 58 ± 17% probability of a M ∼ 6 Parkfield earthquake during 2001–2011.

DROP: Detecting Return-Oriented Programming Malicious Code

NASA Astrophysics Data System (ADS)

Chen, Ping; Xiao, Hai; Shen, Xiaobin; Yin, Xinchun; Mao, Bing; Xie, Li

Return-Oriented Programming (ROP) is a new technique that helps the attacker construct malicious code mounted on x86/SPARC executables without any function call at all. Such technique makes the ROP malicious code contain no instruction, which is different from existing attacks. Moreover, it hides the malicious code in benign code. Thus, it circumvents the approaches that prevent control flow diversion outside legitimate regions (such as W ⊕ X ) and most malicious code scanning techniques (such as anti-virus scanners). However, ROP has its own intrinsic feature which is different from normal program design: (1) uses short instruction sequence ending in "ret", which is called gadget, and (2) executes the gadgets contiguously in specific memory space, such as standard GNU libc. Based on the features of the ROP malicious code, in this paper, we present a tool DROP, which is focused on dynamically detecting ROP malicious code. Preliminary experimental results show that DROP can efficiently detect ROP malicious code, and have no false positives and negatives.

Factors affecting the probability of first year medical student dropout in the UK: a logistic analysis for the intake cohorts of 1980-92.

PubMed

Arulampalam, Wiji; Naylor, Robin; Smith, Jeremy

2004-05-01

In the context of the 1997 Report of the Medical Workforce Standing Advisory Committee, it is important that we develop an understanding of the factors influencing medical school retention rates. To analyse the determinants of the probability that an individual medical student will drop out of medical school during their first year of study. Binomial and multinomial logistic regression analysis of individual-level administrative data on 51 810 students in 21 medical schools in the UK for the intake cohorts of 1980-92 was performed. The overall average first year dropout rate over the period 1980-92 was calculated to be 3.8%. We found that the probability that a student would drop out of medical school during their first year of study was influenced significantly by both the subjects studied at A-level and by the scores achieved. For example, achieving 1 grade higher in biology, chemistry or physics reduced the dropout probability by 0.38% points, equivalent to a fall of 10%. We also found that males were about 8% more likely to drop out than females. The medical school attended also had a significant effect on the estimated dropout probability. Indicators of both the social class and the previous school background of the student were largely insignificant. Policies aimed at increasing the size of the medical student intake in the UK and of widening access to students from non-traditional backgrounds should be informed by evidence that student dropout probabilities are sensitive to measures of A-level attainment, such as subject studied and scores achieved. If traditional entry requirements or standards are relaxed, then this is likely to have detrimental effects on medical schools' retention rates unless accompanied by appropriate measures such as focussed student support.

Violence and vulnerability of female migrants in drop houses in Arizona: the predictable outcome of a chain reaction of violence.

PubMed

Simmons, William Paul; Menjívar, Cecilia; Téllez, Michelle

2015-05-01

This qualitative research study examines the experiences of immigrant women crossing the U.S./Mexico border and the proliferation of "drop houses" in Arizona as a new phenomenon, one that is often marked by kidnappings and sexual assault. Little research has been published on the violence women face on their journey, and the drop houses have almost completely escaped scholarly analysis. We argue that the drop houses must be seen as a consequence of a "state of emergency" declared by policy makers that led to changes in U.S. national and local immigration policies that fueled what we call a "chain reaction of violence." © The Author(s) 2015.

Strategies for Obtaining Probability Samples of Homeless Youth

ERIC Educational Resources Information Center

Golinelli, Daniela; Tucker, Joan S.; Ryan, Gery W.; Wenzel, Suzanne L.

2015-01-01

Studies of homeless individuals typically sample subjects from few types of sites or regions within a metropolitan area. This article focuses on the biases that can result from such a practice. We obtained a probability sample of 419 homeless youth from 41 sites (shelters, drop-in centers, and streets) in four regions of Los Angeles County (LAC).…

Queues with Dropping Functions and General Arrival Processes

PubMed Central

Chydzinski, Andrzej; Mrozowski, Pawel

2016-01-01

In a queueing system with the dropping function the arriving customer can be denied service (dropped) with the probability that is a function of the queue length at the time of arrival of this customer. The potential applicability of such mechanism is very wide due to the fact that by choosing the shape of this function one can easily manipulate several performance characteristics of the queueing system. In this paper we carry out analysis of the queueing system with the dropping function and a very general model of arrival process—the model which includes batch arrivals and the interarrival time autocorrelation, and allows for fitting the actual shape of the interarrival time distribution and its moments. For such a system we obtain formulas for the distribution of the queue length and the overall customer loss ratio. The analytical results are accompanied with numerical examples computed for several dropping functions. PMID:26943171

Seismicity and source spectra analysis in Salton Sea Geothermal Field

NASA Astrophysics Data System (ADS)

Cheng, Y.; Chen, X.

2016-12-01

The surge of "man-made" earthquakes in recent years has led to considerable concerns about the associated hazards. Improved monitoring of small earthquakes would significantly help understand such phenomena and the underlying physical mechanisms. In the Salton Sea Geothermal field in southern California, open access of a local borehole network provides a unique opportunity to better understand the seismicity characteristics, the related earthquake hazards, and the relationship with the geothermal system, tectonic faulting and other physical conditions. We obtain high-resolution earthquake locations in the Salton Sea Geothermal Field, analyze characteristics of spatiotemporal isolated earthquake clusters, magnitude-frequency distributions and spatial variation of stress drops. The analysis reveals spatial coherent distributions of different types of clustering, b-value distributions, and stress drop distribution. The mixture type clusters (short-duration rapid bursts with high aftershock productivity) are predominately located within active geothermal field that correlate with high b-value, low stress drop microearthquake clouds, while regular aftershock sequences and swarms are distributed throughout the study area. The differences between earthquakes inside and outside of geothermal operation field suggest a possible way to distinguish directly induced seismicity due to energy operation versus typical seismic slip driven sequences. The spatial coherent b-value distribution enables in-situ estimation of probabilities for M≥3 earthquakes, and shows that the high large-magnitude-event (LME) probability zones with high stress drop are likely associated with tectonic faulting. The high stress drop in shallow (1-3 km) depth indicates the existence of active faults, while low stress drops near injection wells likely corresponds to the seismic response to fluid injection. I interpret the spatial variation of seismicity and source characteristics as the result of fluid circulation, the fracture network, and tectonic faulting.

Large-Scale Integration of Solid-State Microfluidic Valves With No Moving Parts

DTIC Science & Technology

2005-01-01

compact and diffuse layer is called outer Helmholtz plane ( OHP ). Potential drop across the diffusion layer is called the zeta potential, ζ. As the...Gouy-Chapman model. This is shown in Fig. 3. The plane at x2 is called the outer Helmholtz plane ( OHP ). Then the total double layer capacitance Cd...Enhanced Electro-Osmotic Pumping With Liquid Bridge and Field Effect Flow Rectification, ” Presented in IEEE MEMS 2004 Conference, Maastricht, The

Metolazone

MedlinePlus

... in a class of medications called diuretics ('water pills'). It causes the kidneys to reduce the amount ... of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, ...

Bumetanide

MedlinePlus

... in a class of medications called diuretics ('water pills'). It works by causing the kidneys to get ... of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, ...

Histoplasmosis

MedlinePlus

... is a disease caused by a fungus (or mold) called Histoplasma. The fungus is common in the eastern and central United States. It grows in soil and material contaminated with bat or bird droppings. ...

Modeling Evaporation of Drops of Different Kerosenes

NASA Technical Reports Server (NTRS)

Bellan, Josette; Harstad, Kenneth

2007-01-01

A mathematical model describes the evaporation of drops of a hydrocarbon liquid composed of as many as hundreds of chemical species. The model is intended especially for application to any of several types of kerosenes commonly used as fuels. The concept of continuous thermodynamics, according to which the chemical composition of the evaporating multicomponent liquid is described by use of a probability distribution function (PDF). However, the present model is more generally applicable than is its immediate predecessor.

Performance analysis of signaling protocols on OBS switches

NASA Astrophysics Data System (ADS)

Kirci, Pinar; Zaim, A. Halim

2005-10-01

In this paper, Just-In-Time (JIT), Just-Enough-Time (JET) and Horizon signalling schemes for Optical Burst Switched Networks (OBS) are presented. These signaling schemes run over a core dWDM network and a network architecture based on Optical Burst Switches (OBS) is proposed to support IP, ATM and Burst traffic. In IP and ATM traffic several packets are assembled in a single packet called burst and the burst contention is handled by burst dropping. The burst length distribution in IP traffic is arbitrary between 0 and 1, and is fixed in ATM traffic at 0,5. Burst traffic on the other hand is arbitrary between 1 and 5. The Setup and Setup ack length distributions are arbitrary. We apply the Poisson model with rate λ and Self-Similar model with pareto distribution rate α to identify inter-arrival times in these protocols. We consider a communication between a source client node and a destination client node over an ingress and one or more multiple intermediate switches.We use buffering only in the ingress node. The communication is based on single burst connections in which, the connection is set up just before sending a burst and then closed as soon as the burst is sent. Our analysis accounts for several important parameters, including the burst setup, burst setup ack, keepalive messages and the optical switching protocol. We compare the performance of the three signalling schemes on the network under as burst dropping probability under a range of network scenarios.

Pollination drop in Juniperus communis: response to deposited material.

PubMed

Mugnaini, Serena; Nepi, Massimo; Guarnieri, Massimo; Piotto, Beti; Pacini, Ettore

2007-12-01

The pollination drop is a liquid secretion produced by the ovule and exposed outside the micropyle. In many gymnosperms, pollen lands on the surface of the pollination drop, rehydrates and enters the ovule as the drop retracts. The objective of this work was to study the formation of the pollination drop in Juniperus communis, its carbohydrate composition and the response to deposition of conspecific pollen, foreign pollen and other particulate material, in an attempt to clarify the mechanism of pollination drop retraction. Branches with female cones close to pollination drop secretion were collected. On the first day of pollination drop exposure, an eyelash mounted on a wooden stick with paraffin was used to collect pollen or silica gel particles, which were then deposited by contact with the drop. Volume changes in pollination drops were measured by using a stereomicroscope with a micrometer eyepiece 3 h after deposition. The volume of non-pollinated control drops was also recorded. On the first day of secretion, drops were also collected for sugar analysis by high-performance liquid chromatography. The pollination drop persisted for about 12 d if not pollinated, and formed again after removal for up to four consecutive days. After pollination with viable conspecific pollen, the drop retracted quickly and did not form again. Partial withdrawal occurred after deposition of other biological and non-biological material. Fructose was the dominant sugar; glucose was also present but at a much lower percentage. Sugar analysis confirmed the general trend of fructose dominance in gymnosperm pollination drops. Complete pollination drop withdrawal appears to be triggered by a biochemical mechanism resulting from interaction between pollen and drop constituents. The results of particle deposition suggest the existence of a non-specific, particle-size-dependent mechanism that induces partial pollination drop withdrawal. These results suggest that the non-specific response may decrease the probability of pollen landing on the drop, reducing pollination efficiency.

Pollination Drop in Juniperus communis: Response to Deposited Material

PubMed Central

Mugnaini, Serena; Nepi, Massimo; Guarnieri, Massimo; Piotto, Beti; Pacini, Ettore

2007-01-01

Background and Aims The pollination drop is a liquid secretion produced by the ovule and exposed outside the micropyle. In many gymnosperms, pollen lands on the surface of the pollination drop, rehydrates and enters the ovule as the drop retracts. The objective of this work was to study the formation of the pollination drop in Juniperus communis, its carbohydrate composition and the response to deposition of conspecific pollen, foreign pollen and other particulate material, in an attempt to clarify the mechanism of pollination drop retraction. Method Branches with female cones close to pollination drop secretion were collected. On the first day of pollination drop exposure, an eyelash mounted on a wooden stick with paraffin was used to collect pollen or silica gel particles, which were then deposited by contact with the drop. Volume changes in pollination drops were measured by using a stereomicroscope with a micrometer eyepiece 3 h after deposition. The volume of non-pollinated control drops was also recorded. On the first day of secretion, drops were also collected for sugar analysis by high-performance liquid chromatography. Key Results The pollination drop persisted for about 12 d if not pollinated, and formed again after removal for up to four consecutive days. After pollination with viable conspecific pollen, the drop retracted quickly and did not form again. Partial withdrawal occurred after deposition of other biological and non-biological material. Fructose was the dominant sugar; glucose was also present but at a much lower percentage. Conclusions Sugar analysis confirmed the general trend of fructose dominance in gymnosperm pollination drops. Complete pollination drop withdrawal appears to be triggered by a biochemical mechanism resulting from interaction between pollen and drop constituents. The results of particle deposition suggest the existence of a non-specific, particle-size-dependent mechanism that induces partial pollination drop withdrawal. These results suggest that the non-specific response may decrease the probability of pollen landing on the drop, reducing pollination efficiency. PMID:17942592

Effect of rasanjana madhu ashchyotana in netra abhishyanda (mucopurulent conjunctivitis).

PubMed

Bhardwaj, Atul; Tanwar, Manoj

2011-07-01

To evaluate the comparative efficacy of Ayurvedic formulation a Rasanjana Madhu (RM) eye drops and Honey Rose (HR) water eye drops in Netra Abhishyanda in mucopurulent conjunctivitis, the current study is planned. Total of 35 patients attending the outpatient department of Shalakya Tantra at R. G. G. Postgraduate Ayurvedic College, Paprola, Distt. Kangra, Himachal Pradesh with characteristic features of Netra Abhishyanda were selected for the present study. Twenty patients were given trial drug, i.e., RM eye drops, while 15 patients were given HR eye drops. Random sampling technique was adopted for the present study. The duration of the treatment was 7 days with 1 week follow-up. Patients receiving the trial group demonstrated reduction of redness, burning sensation, lacrimation, photophobia, foreign body sensation, discharge, and congestion, which were statistically significant with 93% patients cured or markedly improved category. Signs and symptoms stated above were also statistically reduced with HR eye drops, probably because of well-documented hygroscopic and bacteriocidal properties of honey. Based on the study, it can be concluded that, RM eye drops are very effective in the management of Netra Abhishyanda viz. Infective conjunctivitis.

Effect of Rasanjana Madhu Ashchyotana in Netra Abhishyanda (Mucopurulent Conjunctivitis)

PubMed Central

Bhardwaj, Atul; Tanwar, Manoj

2011-01-01

To evaluate the comparative efficacy of Ayurvedic formulation a Rasanjana Madhu (RM) eye drops and Honey Rose (HR) water eye drops in Netra Abhishyanda in mucopurulent conjunctivitis, the current study is planned. Total of 35 patients attending the outpatient department of Shalakya Tantra at R. G. G. Postgraduate Ayurvedic College, Paprola, Distt. Kangra, Himachal Pradesh with characteristic features of Netra Abhishyanda were selected for the present study. Twenty patients were given trial drug, i.e., RM eye drops, while 15 patients were given HR eye drops. Random sampling technique was adopted for the present study. The duration of the treatment was 7 days with 1 week follow-up. Patients receiving the trial group demonstrated reduction of redness, burning sensation, lacrimation, photophobia, foreign body sensation, discharge, and congestion, which were statistically significant with 93% patients cured or markedly improved category. Signs and symptoms stated above were also statistically reduced with HR eye drops, probably because of well-documented hygroscopic and bacteriocidal properties of honey. Based on the study, it can be concluded that, RM eye drops are very effective in the management of Netra Abhishyanda viz. Infective conjunctivitis. PMID:22529652

Workers on the margin: who drops health coverage when prices rise?

PubMed

Okeke, Edward N; Hirth, Richard A; Grazier, Kyle

2010-01-01

We revisit the question of price elasticity of employer-sponsored insurance (ESI) take-up by directly examining changes in the take-up of ESI at a large firm in response to exogenous changes in employee premium contributions. We find that, on average, a 10% increase in the employee's out-of-pocket premium increases the probability of dropping coverage by approximately 1%. More importantly, we find heterogeneous impacts: married workers are much more price-sensitive than single employees, and lower-paid workers are disproportionately more likely to drop coverage than higher-paid workers. Elasticity estimates for employees below the 25th percentile of salary distribution in our sample are nearly twice the average.

A novel generation of 3D SAR-based passive micromixer: efficient mixing and low pressure drop at a low Reynolds number

NASA Astrophysics Data System (ADS)

Viktorov, Vladimir; Nimafar, Mohammad

2013-05-01

This study introduces a novel generation of 3D splitting and recombination (SAR) passive micromixer with microstructures placed on the top and bottom floors of microchannels called a ‘chain mixer’. Both experimental verification and numerical analysis of the flow structure of this type of passive micromixer have been performed to evaluate the mixing performance and pressure drop of the microchannel, respectively. We propose here two types of chain mixer—chain 1 and chain 2—and compare their mixing performance and pressure drop with other micromixers, T-, o- and tear-drop micromixers. Experimental tests carried out in the laminar flow regime with a low Reynolds number range, 0.083 ≤ Re ≤ 4.166, and image-based techniques are used to evaluate the mixing efficiency. Also, the computational fluid dynamics code, ANSYS FLUENT-13.0 has been used to analyze the flow and pressure drop in the microchannel. Experimental results show that the chain and tear-drop mixer's efficiency is very high because of the SAR process: specifically, an efficiency of up to 98% can be achieved at the tested Reynolds number. The results also show that chain mixers have a lower required pressure drop in comparison with a tear-drop micromixer.

Bronchiolitis - discharge

MedlinePlus

... bronchiolitis. Your health care provider may prescribe such medicine for your child. DO NOT give your child decongestant nose drops, antihistamines, or any other cold medicines unless your child's doctor tells you to. When to Call the ...

Measuring the rebound resilience of a bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2012-09-01

Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property 'rebound resilience' and express it as the ratio of the rebound height to the initial drop height of the ball. We determine the rebound resilience for three different types of ball by calculating the coefficient of restitution of the ball-surface combination from the experimentally measurable physical quantities, such as initial drop height and time interval between successive bounces. Using these we also determine the contact time of balls with the surface of impact. For measurements we have used audio, motion and surface-temperature sensors that were interfaced through a USB port with a computer.

Corona emission thresholds for three types of hydrometeor interaction in thunderclouds

NASA Astrophysics Data System (ADS)

Blyth, A. M.; Christian, H. J.; Latham, J.

1998-06-01

Laboratory studies have been conducted of the conditions under which glancing collisions, at relative velocities V characteristic of those occurring in thunderstorms, of three types of hydrometeor pairs of precipitation dimension (such as (1) warm drop pairs, (2) supercooled drop pairs, and (3) a supercooled drop and a graupel pellet) produce a corona discharge in an electric field E. In each case, the observed corona is emitted at the tip of an ephemeral liquid filament, of length greater than the dimensions of the interacting hydrometeors, drawn out during each interaction. For each type of hydrometeor pair, the probability f that corona was produced during an interaction increased steadily from zero for increasing values of E above about 150 kV/m, and was significantly in excess of 50% for values of E = 400 kV/m, which is probably about the maximum ambient value occurring in a thunderstorm. We conclude that if the associated hydrometeors are present in strongly electrified regions of thunderstorms (unlikely for interaction type 1 but manifestly possible for types 2 and 3, corona initiation leading to the production of lightning could result from each of the three types of interaction studied.

Energy transfer mechanism and probability analysis of submarine pipe laterally impacted by dropped objects

NASA Astrophysics Data System (ADS)

Liang, Jing; Yu, Jian-xing; Yu, Yang; Lam, W.; Zhao, Yi-yu; Duan, Jing-hui

2016-06-01

Energy transfer ratio is the basic-factor affecting the level of pipe damage during the impact between dropped object and submarine pipe. For the purpose of studying energy transfer and damage mechanism of submarine pipe impacted by dropped objects, series of experiments are designed and carried out. The effective yield strength is deduced to make the quasi-static analysis more reliable, and the normal distribution of energy transfer ratio caused by lateral impact on pipes is presented by statistic analysis of experimental results based on the effective yield strength, which provides experimental and theoretical basis for the risk analysis of submarine pipe system impacted by dropped objects. Failure strains of pipe material are confirmed by comparing experimental results with finite element simulation. In addition, impact contact area and impact time are proved to be the major influence factors of energy transfer by sensitivity analysis of the finite element simulation.

High School Dropouts and Sexually Transmitted Infections

PubMed Central

Anderson, D. Mark; Pörtner, Claus C.

2015-01-01

People who drop out of high school fare worse in many aspects of life. We analyze the relationship between dropping out of high school and the probability of contracting a sexually transmitted infection (STI). Previous studies on the relationship between dropout status and sexual outcomes have not empirically addressed unobserved heterogeneity at the individual level. Using fixed effects estimators, we find evidence supporting a positive relationship between dropping out of high school and the risk of contracting an STI for females. Furthermore, we present evidence that illustrates differences between the romantic partners of dropouts versus enrolled students. These differences suggest that female dropouts may be more susceptible to contracting STIs because they partner with significantly different types of people than non-dropouts. Our results point to a previously undocumented benefit of encouraging those at risk of dropping out to stay in school longer. PMID:25705058

Size of the top jet drop produced by bubble bursting

NASA Astrophysics Data System (ADS)

Berny, Alexis; Deike, Luc; Popinet, Stéphane; Seon, Thomas

2017-11-01

When a bubble is located on a liquid-air interface, it eventually bursts. First, the bubble cap shatters and produces film drops. Then, the cavity collapses, a tiny liquid jet rises and, depending on bubble radius and liquid parameters, it can eventually break-up and release the so-called jet drops. We perform numerical simulations, using the free software basilisk, to determine and discuss the regime of existence and the size of the first liquid jet droplets. We first validate the numerical scheme by comparing our results with recent experimental data. We then extend our numerical study to a wider range of control parameters in order to enrich our knowledge of the jet drops production. Finally, we show and interpret our results using a scaling law approach and basic physical arguments. This allows us to untangle the intricate roles of viscosity, gravity, and surface tension in the end pinching of the bubble bursting jet.

Simultaneous dense coding affected by fluctuating massless scalar field

NASA Astrophysics Data System (ADS)

Huang, Zhiming; Ye, Yiyong; Luo, Darong

2018-04-01

In this paper, we investigate the simultaneous dense coding (SDC) protocol affected by fluctuating massless scalar field. The noisy model of SDC protocol is constructed and the master equation that governs the SDC evolution is deduced. The success probabilities of SDC protocol are discussed for different locking operators under the influence of vacuum fluctuations. We find that the joint success probability is independent of the locking operators, but other success probabilities are not. For quantum Fourier transform and double controlled-NOT operators, the success probabilities drop with increasing two-atom distance, but SWAP operator is not. Unlike the SWAP operator, the success probabilities of Bob and Charlie are different. For different noisy interval values, different locking operators have different robustness to noise.

Presidential Green Chemistry Challenge: 2014 Small Business Award

EPA Pesticide Factsheets

Presidential Green Chemistry Challenge 2014 award winner, Amyris, engineered yeast to make a chemical called farnesene, which is a building block hydrocarbon that can be converted into a renewable, drop-in replacement for petroleum diesel.

Ceraunius Fossae

NASA Image and Video Library

2012-02-07

The north-south trending fractures and graben block down-dropped between two fractures in this region are called Ceraunius Fossae and are likely related to Alba Mons to the north shown in this image from NASA 2001 Mars Odyssey spacecraft.

Quinoa starch granules as stabilizing particles for production of Pickering emulsions.

PubMed

Rayner, Marilyn; Sjöö, Malin; Timgren, Anna; Dejmek, Petr

2012-01-01

Intact starch granules isolated from quinoa (Chenopodium quinoa Willd.) were used to stabilize emulsion drops in so-called Pickering emulsions. Miglyol 812 was used as dispersed phase and a phosphate buffer (pH7) with different salt (NaCl) concentrations was used as the continuous phase. The starch granules were hydrophobically modified to different degrees by octenyl succinic anhydride (OSA) or by dry heat treatment at 120 degrees C in order to study the effect on the resulting emulsion drop size. The degree of OSA-modification had a low to moderate impact on drop size. The highest level of modification (4.66%) showed the largest mean drop size, and lowest amount of free starch, which could be an effect of a higher degree of aggregation of the starch granules and, thereby, also the emulsion drops stabilized by them. The heat treated starch granules had a poor stabilizing ability and only the starch heated for the longest time (150 min at 120 degrees C) had a better emulsifying capacity than the un-modified native starch granules. The effect of salt concentration was rather limited. However, an increased concentration of salt slightly increased the mean drop size and the elastic modulus.

On the glitches in the force transmitted by an electrodynamic exciter to a structure

NASA Technical Reports Server (NTRS)

Rao, Dantam K.

1987-01-01

Around resonance, the force transmitted by an exciter into a structure will be smaller or greater than a reference force generated by its coils due to electromechanical interaction. A simple analysis is presented which reveals how this phenomenon of force drop-off is controlled by three factors. The first factor, called Armature Mass Factor, describes a purely mechanical interaction between the structure and the exciter. The electromechanical energy conversion and its interaction with the structure yields two additional factors, called Electrical Resistance and Electrical Inductance Factors. They describe the effects of coil resistance, inductance and magnetic field strength relative to structural damping and stiffness. Present analysis indicates that, under proper circumstances, more than 90 percent of the force drop-off can be eliminated if armature-to-structure mass ratio is smaller or equal to half of modal loss factor.

Spent fuel cask handling at an operating nuclear power plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pal, A.C.

1988-01-01

The importance of spent fuel handling at operating nuclear power plants cannot be overstated. Because of its highly radioactive nature, however, spent fuel must be handled in thick, lead-lined containers or casks. Thus, all casks for spent fuel handling are heavy loads by the US Nuclear Regulatory Commission's definition, and any load-drop must be evaluated for its potential to damage safety-related equipment. Nuclear Regulatory Guide NUREG-0612 prescribes the regulatory requirements of alternative heavy-load-handling methodologies such as (a) by providing cranes that meet the requirements of NUREG-0554, which shall be called the soft path, or (b) by providing protective devices atmore » all postulated load-drop areas to prevent any damage to safety-related equipment, which shall be called the hard path. The work reported in this paper relates to cask handling at New York Power Authority's James A. FitzPatrick (JAF) plant.« less

Reduction, partial evaporation, and spattering - Possible chemical and physical processes in fluid drop chondrule formation

NASA Technical Reports Server (NTRS)

King, E. A.

1983-01-01

The major chemical differences between fluid drop chondrules and their probable parent materials may have resulted from the loss of volatiles such as S, H2O, Fe, and volatile siderophile elements by partial evaporation during the chondrule-forming process. Vertical access solar furnace experiments in vacuum and hydrogen have demonstrated such chemical fractionation trends using standard rock samples. The formation of immiscible iron droplets and spherules by in situ reduction of iron from silicate melt and the subsequent evaporation of the iron have been observed directly. During the time that the main sample bead is molten, many small spatter spherules are thrown off the main bead, thereby producing many additional chondrule-like melt spherules that cool rapidly and generate a population of spherules with size frequency distribution characteristics that closely approximate some populations of fluid drop chondrules in chondrites. It is possible that spatter-produced fluid drop chondrules dominate the meteoritic fluid drop chondrule populations. Such meteoritic chondrule populations should be chemically related by various relative amounts of iron and other volatile loss by vapor fractionation.

Public telesurveillance service for frail elderly living at home, outcomes and cost evolution: a quasi experimental design with two follow-ups.

PubMed

Vincent, Claude; Reinharz, Daniel; Deaudelin, Isabelle; Garceau, Mathieu; Talbot, Lise R

2006-07-07

Telesurveillance is a technologically based modality that allows the surveillance of patients in the natural setting, mainly home. It is based on communication technologies to relay information between a patient and a central call center where services are coordinated. Different types of telesurveillance systems have been implemented, some being staffed with non-health professionals and others with health professional, mainly nurses. Up to now, only telesurveillance services staffed with non-health professionals have been shown to be effective and efficient. The objective of this study was to document outcomes and cost evolution of a nurse-staffed telesurveillance system for frail elderly living at home. A quasi experimental design over a nine-month period was done. Patients (n = 38) and caregivers (n = 38) were selected by health professionals from two local community health centers. To be eligible, elders had to be over 65, live at home with a permanent physical, slight cognitive or motor disability or both and have a close relative (the caregiver) willing to participate to the study. These disabilities had to hinder the accomplishment of daily life activities deemed essential to continue living at home safely. Three data sources were used: patient files, telesurveillance center's quarterly reports and personal questionnaires (Modified Mini-Mental State, Functional Autonomy Measurement System, Life Event Checklist, SF-12, Life-H, Quebec User Evaluation of Satisfaction with Assistive Technology, Caregiver Burden). The telesurveillance technology permitted, among various functionalities, bi-directional communication (speaker-receiver) between the patient and the response center. A total of 957 calls for 38 registered clients over a 6-month period was recorded. Only 48 (5.0%) of the calls were health-related. No change was reported in the elders' quality of life and daily activity abilities. Satisfaction was very high. Caregivers' psychological burden decreased substantially. On a 3 months period, length of hospital stays dropped from 13 to 4 days, and home care services decreased from 18 to 10 visits/client. Total cost of health and social public services used per client dropped by 17% after the first 3 months and by 39% in the second 3 months. The ratio of 0.50 calls per client to the call center for health events is three times higher than that reported in the literature. This difference is probably attributable to the fact that nurses rather than non-health professional personnel were available to answer the clients' questions about their health and medications. Cost evolution showed that registering older adults at a telesurveillance center staffed by nurses, upon a health professional recommendation, costs the health care system less and does not have any negative effects on the well-being of the individuals and their families. Telesurveillance for the elderly is effective and efficient.

In vitro differentiation of mouse embryonic stem (mES) cells using the hanging drop method.

PubMed

Wang, Xiang; Yang, Phillip

2008-07-23

Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, This promising of science is leading scientists to investigate the possibility of cell-based therapies to treat disease. When culture in suspension without antidifferentiation factors, embryonic stem cells spontaneously differentiate and form three-dimensional multicellular aggregates. These cell aggregates are called embryoid bodies(EB). Hanging drop culture is a widely used EB formation induction method. The rounded bottom of hanging drop allows the aggregation of ES cells which can provide mES cells a good environment for forming EBs. The number of ES cells aggregatied in a hanging drop can be controlled by varying the number of cells in the initial cell suspension to be hung as a drop from the lid of Petri dish. Using this method we can reproducibly form homogeneous EBs from a predetermined number of ES cells.

Rapid detection of bacteria in foods and biological fluids

NASA Technical Reports Server (NTRS)

Fealey, R. D.; Renner, W.

1973-01-01

Simple and inexpensive apparatus, called "redox monitoring cell," rapidly detects presence of bacteria. Bacteria is detected by measuring drop in oxygen content in test solution. Apparatus consists of vial with two specially designed electrodes connected to sensitive voltmeter.

Site specific probability of passive acoustic detection of humpback whale calls from single fixed hydrophones.

PubMed

Helble, Tyler A; D'Spain, Gerald L; Hildebrand, John A; Campbell, Gregory S; Campbell, Richard L; Heaney, Kevin D

2013-09-01

Passive acoustic monitoring of marine mammal calls is an increasingly important method for assessing population numbers, distribution, and behavior. A common mistake in the analysis of marine mammal acoustic data is formulating conclusions about these animals without first understanding how environmental properties such as bathymetry, sediment properties, water column sound speed, and ocean acoustic noise influence the detection and character of vocalizations in the acoustic data. The approach in this paper is to use Monte Carlo simulations with a full wave field acoustic propagation model to characterize the site specific probability of detection of six types of humpback whale calls at three passive acoustic monitoring locations off the California coast. Results show that the probability of detection can vary by factors greater than ten when comparing detections across locations, or comparing detections at the same location over time, due to environmental effects. Effects of uncertainties in the inputs to the propagation model are also quantified, and the model accuracy is assessed by comparing calling statistics amassed from 24,690 humpback units recorded in the month of October 2008. Under certain conditions, the probability of detection can be estimated with uncertainties sufficiently small to allow for accurate density estimates.

Site specific passive acoustic detection and densities of humpback whale calls off the coast of California

NASA Astrophysics Data System (ADS)

Helble, Tyler Adam

Passive acoustic monitoring of marine mammal calls is an increasingly important method for assessing population numbers, distribution, and behavior. Automated methods are needed to aid in the analyses of the recorded data. When a mammal vocalizes in the marine environment, the received signal is a filtered version of the original waveform emitted by the marine mammal. The waveform is reduced in amplitude and distorted due to propagation effects that are influenced by the bathymetry and environment. It is important to account for these effects to determine a site-specific probability of detection for marine mammal calls in a given study area. A knowledge of that probability function over a range of environmental and ocean noise conditions allows vocalization statistics from recordings of single, fixed, omnidirectional sensors to be compared across sensors and at the same sensor over time with less bias and uncertainty in the results than direct comparison of the raw statistics. This dissertation focuses on both the development of new tools needed to automatically detect humpback whale vocalizations from single-fixed omnidirectional sensors as well as the determination of the site-specific probability of detection for monitoring sites off the coast of California. Using these tools, detected humpback calls are "calibrated" for environmental properties using the site-specific probability of detection values, and presented as call densities (calls per square kilometer per time). A two-year monitoring effort using these calibrated call densities reveals important biological and ecological information on migrating humpback whales off the coast of California. Call density trends are compared between the monitoring sites and at the same monitoring site over time. Call densities also are compared to several natural and human-influenced variables including season, time of day, lunar illumination, and ocean noise. The results reveal substantial differences in call densities between the two sites which were not noticeable using uncorrected (raw) call counts. Additionally, a Lombard effect was observed for humpback whale vocalizations in response to increasing ocean noise. The results presented in this thesis develop techniques to accurately measure marine mammal abundances from passive acoustic sensors.

Analysis of random drop for gateway congestion control. M.S. Thesis

NASA Technical Reports Server (NTRS)

Hashem, Emam Salaheddin

1989-01-01

Lately, the growing demand on the Internet has prompted the need for more effective congestion control policies. Currently No Gateway Policy is used to relieve and signal congestion, which leads to unfair service to the individual users and a degradation of overall network performance. Network simulation was used to illustrate the character of Internet congestion and its causes. A newly proposed gateway congestion control policy, called Random Drop, was considered as a promising solution to the pressing problem. Random Drop relieves resource congestion upon buffer overflow by choosing a random packet from the service queue to be dropped. The random choice should result in a drop distribution proportional to the bandwidth distribution among all contending TCP connections, thus applying the necessary fairness. Nonetheless, the simulation experiments demonstrate several shortcomings with this policy. Because Random Drop is a congestion control policy, which is not applied until congestion has already occurred, it usually results in a high drop rate that hurts too many connections including well-behaved ones. Even though the number of packets dropped is different from one connection to another depending on the buffer utilization upon overflow, the TCP recovery overhead is high enough to neutralize these differences, causing unfair congestion penalties. Besides, the drop distribution itself is an inaccurate representation of the average bandwidth distribution, missing much important information about the bandwidth utilization between buffer overflow events. A modification of Random Drop to do congestion avoidance by applying the policy early was also proposed. Early Random Drop has the advantage of avoiding the high drop rate of buffer overflow. The early application of the policy removes the pressure of congestion relief and allows more accurate signaling of congestion. To be used effectively, algorithms for the dynamic adjustment of the parameters of Early Random Drop to suite the current network load must still be developed.

Insights from the pollination drop proteome and the ovule transcriptome of Cephalotaxus at the time of pollination drop production

PubMed Central

Pirone-Davies, Cary; Prior, Natalie; von Aderkas, Patrick; Smith, Derek; Hardie, Darryl; Friedman, William E.; Mathews, Sarah

2016-01-01

Background and Aims Many gymnosperms produce an ovular secretion, the pollination drop, during reproduction. The drops serve as a landing site for pollen, but also contain a suite of ions and organic compounds, including proteins, that suggests diverse roles for the drop during pollination. Proteins in the drops of species of Chamaecyparis, Juniperus, Taxus, Pseudotsuga, Ephedra and Welwitschia are thought to function in the conversion of sugars, defence against pathogens, and pollen growth and development. To better understand gymnosperm pollination biology, the pollination drop proteomes of pollination drops from two species of Cephalotaxus have been characterized and an ovular transcriptome for C. sinensis has been assembled. Methods Mass spectrometry was used to identify proteins in the pollination drops of Cephalotaxus sinensis and C. koreana. RNA-sequencing (RNA-Seq) was employed to assemble a transcriptome and identify transcripts present in the ovules of C. sinensis at the time of pollination drop production. Key Results About 30 proteins were detected in the pollination drops of both species. Many of these have been detected in the drops of other gymnosperms and probably function in defence, polysaccharide metabolism and pollen tube growth. Other proteins appear to be unique to Cephalotaxus, and their putative functions include starch and callose degradation, among others. Together, the proteins appear either to have been secreted into the drop or to occur there due to breakdown of ovular cells during drop production. Ovular transcripts represent a wide range of gene ontology categories, and some may be involved in drop formation, ovule development and pollen–ovule interactions. Conclusions The proteome of Cephalotaxus pollination drops shares a number of components with those of other conifers and gnetophytes, including proteins for defence such as chitinases and for carbohydrate modification such as β-galactosidase. Proteins likely to be of intracellular origin, however, form a larger component of drops from Cephalotaxus than expected from studies of other conifers. This is consistent with the observation of nucellar breakdown during drop formation in Cephalotaxus. The transcriptome data provide a framework for understanding multiple metabolic processes that occur within the ovule and the pollination drop just before fertilization. They reveal the deep conservation of WUSCHEL expression in ovules and raise questions about whether any of the S-locus transcripts in Cephalotaxus ovules might be involved in pollen–ovule recognition. PMID:27045089

Numerical study of effect of the gas-coolant free surface on the droplet fragmentation behavior of coolants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, H.X.; Anh, B.V.; Dinh, T.N.

1999-07-01

This paper presents results of a numerical investigation on the behavior of melt drops falling in a gas (vapor) space and then penetrating into a liquid volume through the gas-liquid interface. The phenomenon studied here is, usually, observed when a liquid drop falls through air into a water pool and is, specially, of interest when a hypothetical severe reactor core meltdown accident is considered. The objective of this work is to study the effect of the gas-liquid interface on the dynamic evolution of the interaction area between the fragmenting melt drop and water. In the present study, the Navier-Stokes equationsmore » are solved for three phases (gas, liquid and melt-drop) using a higher-order, explicit, numerical method, called Cubic-Interpolated Pseudo-Particle (CIP) method, which is employed in combination with an advanced front-capturing scheme, named the Level Set Algorithm (LSA). By using this method, reasonable physical pictures of droplet deformation and fragmentation during movement in a stationary uniform water pool, and in a gas-liquid two-layer volume, is simulated. Effect of the gas-liquid interface on the drop deformation and fragmentation is analyzed by comparing the simulation results obtained for the two cases. Effects of the drop geometry, and of the flow conditions, on the behavior of the melt drop are also analyzed.« less

Usage of drip drops as stimuli in an auditory P300 BCI paradigm.

PubMed

Huang, Minqiang; Jin, Jing; Zhang, Yu; Hu, Dewen; Wang, Xingyu

2018-02-01

Recently, many auditory BCIs are using beeps as auditory stimuli, while beeps sound unnatural and unpleasant for some people. It is proved that natural sounds make people feel comfortable, decrease fatigue, and improve the performance of auditory BCI systems. Drip drop is a kind of natural sounds that makes humans feel relaxed and comfortable. In this work, three kinds of drip drops were used as stimuli in an auditory-based BCI system to improve the user-friendness of the system. This study explored whether drip drops could be used as stimuli in the auditory BCI system. The auditory BCI paradigm with drip-drop stimuli, which was called the drip-drop paradigm (DP), was compared with the auditory paradigm with beep stimuli, also known as the beep paradigm (BP), in items of event-related potential amplitudes, online accuracies and scores on the likability and difficulty to demonstrate the advantages of DP. DP obtained significantly higher online accuracy and information transfer rate than the BP ( p  < 0.05, Wilcoxon signed test; p  < 0.05, Wilcoxon signed test). Besides, DP obtained higher scores on the likability with no significant difference on the difficulty ( p  < 0.05, Wilcoxon signed test). The results showed that the drip drops were reliable acoustic materials as stimuli in an auditory BCI system.

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

PubMed

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

2013-11-01

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.

The role of rain in dispersal of the primary inoculum of Plasmopara viticola.

PubMed

Rossi, Vittorio; Caffi, Tito

2012-02-01

Although primary infection of grapevines by Plasmopara viticola requires splash dispersal of inoculum from soil to leaves, little is known about the role of rain in primary inoculum dispersal. Distribution of rain splashes from soil to grapevine canopy was evaluated over 20 rain periods (0.2 to 64.2 mm of rain) with splash samplers placed within the canopy. Samplers at 40, 80, and 140 cm above the soil caught 4.4, 0.03, and 0.003 drops/cm(2) of sampler area, respectively. Drops caught at 40 and 80 cm (1.5 cm in diameter) were larger than drops at 140 cm (1.3 cm). Leaf coverage by splashed drops, total drop number, and drop size increased with an increase in the maximum intensity of rain (mm/h) during any rain period. Any rainfall led to infection in potted grapevines placed outside on leaf litter containing oospores, if the litter contained germinated oospores at the time of rain; infection severity was unrelated to rain amount or intensity. Results from vineyards also indicate that any rain can carry P. viticola inoculum from soil to leaves and should be considered a splash event in disease prediction systems. Sampling for early disease detection should focus on the lower canopy, where the probability of splash impact is greatest.

Reticulo-rumen temperature as a predictor of calving time in primiparous and parous Holstein females.

PubMed

Costa, J B G; Ahola, J K; Weller, Z D; Peel, R K; Whittier, J C; Barcellos, J O J

2016-06-01

The objective of this research was to define and analyze drops in reticulo-rumen temperature (Trr) as an indicator of calving time in Holstein females. Data were collected from 111 primiparous and 150 parous Holstein females between November 2012 and March 2013. Between -15 and -5 d relative to anticipated calving date, each female received an orally administered temperature sensing reticulo-rumen bolus that collected temperatures hourly. Daily mean Trr was calculated from d -5 to 0 relative to using all Trr values (A-Trr) or only Trr values ≥37.7°C (W-Trr) not altered by water intake. To identify a Trr drop, 2 methodologies for computing the baseline temperature were used. Generalized linear models (GLM) were used to estimate the probability of calving within the next 12 or 24 h for primiparous, parous, and all females, based on the size of the Trr drop. For all GLM, a large drop in Trr corresponded with a large estimated probability of calving. The predictive power of the GLM was assessed using receiver-operating characteristic (ROC) curves. The ROC curve analyses showed that all models, regardless of methodology in calculation of the baseline or tested category (primiparous or parous), were able to predict calving; however, area under the ROC curve values, an indication of prediction quality, were greater for methods predicting calving within 24 h. Further comparisons between GLM for primiparous and parous, and using baseline 1 and 2, provide insight on the differences in predictive performance. Based on the GLM, Trr drops of 0.2, 0.3, and 0.4°C were identified as useful indicators of parturition and further analyzed using sensitivity, specificity, and diagnostic odds ratios. Based on sensitivity, specificity, and diagnostic odds ratios, the best indicator of calving was an average Trr drop ≥0.2°C, regardless of methodology used to compute the baseline or category of animal evaluated. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Changes in tropical precipitation cluster size distributions under global warming

NASA Astrophysics Data System (ADS)

Neelin, J. D.; Quinn, K. M.

2016-12-01

The total amount of precipitation integrated across a tropical storm or other precipitation feature (contiguous clusters of precipitation exceeding a minimum rain rate) is a useful measure of the aggregate size of the disturbance. To establish baseline behavior in current climate, the probability distribution of cluster sizes from multiple satellite retrievals and National Center for Environmental Prediction (NCEP) reanalysis is compared to those from Coupled Model Intercomparison Project (CMIP5) models and the Geophysical Fluid Dynamics Laboratory high-resolution atmospheric model (HIRAM-360 and -180). With the caveat that a minimum rain rate threshold is important in the models (which tend to overproduce low rain rates), the models agree well with observations in leading properties. In particular, scale-free power law ranges in which the probability drops slowly with increasing cluster size are well modeled, followed by a rapid drop in probability of the largest clusters above a cutoff scale. Under the RCP 8.5 global warming scenario, the models indicate substantial increases in probability (up to an order of magnitude) of the largest clusters by the end of century. For models with continuous time series of high resolution output, there is substantial spread on when these probability increases for the largest precipitation clusters should be detectable, ranging from detectable within the observational period to statistically significant trends emerging only in the second half of the century. Examination of NCEP reanalysis and SSMI/SSMIS series of satellite retrievals from 1979 to present does not yield reliable evidence of trends at this time. The results suggest improvements in inter-satellite calibration of the SSMI/SSMIS retrievals could aid future detection.

Poster — Thur Eve — 49: Unexpected Output Drops: Pitted Blackholes in Tungsten

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hudson, A; Pierce, G; University of Calgary, Department of Oncology, Calgary AB

2014-08-15

During the daily measurement of radiation output of a 6 MV beam on a Varian Trilogy Linear Accelerator the output dropped below 2% and initiated a call to action by physics to determine the cause. Over the course of weeks the cause of the issue was diagnosed to be a defect in the target, resulting in a drop in output and an asymmetry of the beam. Steps were taken to return the machine to clinical service while parts were on order while ensuring the safety of patient treatment. The machine target was replaced and the machine continues to operate asmore » expected. A drop in output is usually a rarity and a defect in the target is possibly more rare. This experience demonstrated the importance of routine QC measurement, recording and analyzing daily output and symmetry values. In addition, this event showcased the importance of a multi-disciplinary approach in a high-pressure situation to effectively troubleshoot unique events to ensure consistence, safety patient treatment.« less

Evaporation-triggered microdroplet nucleation and the four life phases of an evaporating Ouzo drop

NASA Astrophysics Data System (ADS)

Tan, Huanshu; Diddens, Christian; Lv, Pengyu; Kuerten, J. G. M.; Zhang, Xuehua; Lohse, Detlef

2016-11-01

Evaporating liquid droplets are omnipresent in nature and technology, such as in inkjet printing, coating, deposition of materials, medical diagnostics, agriculture, the food industry, cosmetics, or spills of liquids. Here we show that the evaporation of such ternary mixtures can trigger a phase transition and the nucleation of microdroplets of one of the components of the mixture. As a model system, we pick a sessile Ouzo droplet (as known from daily life) and reveal and theoretically explain its four life phases: In phase I, the spherical cap-shaped droplet remains transparent while the more volatile ethanol is evaporating, preferentially at the rim of the drop because of the singularity there. This leads to a local ethanol concentration reduction and correspondingly to oil droplet nucleation there. This is the beginning of phase II, in which oil microdroplets quickly nucleate in the whole drop, leading to its milky color that typifies the so-called "Ouzo effect." Once all ethanol has evaporated, the drop, which now has a characteristic nonspherical cap shape, has become clear again, with a water drop sitting on an oil ring (phase III), finalizing the phase inversion. Finally, in phase IV, all water has evaporated, leaving behind a tiny spherical cap-shaped oil drop.

Effect of soil moisture content on the splash phenomenon reproducibility.

PubMed

Ryżak, Magdalena; Bieganowski, Andrzej; Polakowski, Cezary

2015-01-01

One of the methods for testing splash (the first phase of water erosion) may be an analysis of photos taken using so-called high-speed cameras. The aim of this study was to determine the reproducibility of measurements using a single drop splash of simulated precipitation. The height from which the drops fell resulted in a splash of 1.5 m. Tests were carried out using two types of soil: Eutric Cambisol (loamy silt) and Orthic Luvisol (sandy loam); three initial pressure heads were applied equal to 16 kPa, 3.1 kPa, and 0.1 kPa. Images for one, five, and 10 drops were recorded at a rate of 2000 frames per second. It was found that (i) the dispersion of soil caused by the striking of the 1st drop was significantly different from the splash impact caused by subsequent drops; (ii) with every drop, the splash phenomenon proceeded more reproducibly, that is, the number of particles of soil and/or water that splashed were increasingly close to each other; (iii) the number of particles that were detached during the splash were strongly correlated with its surface area; and (iv) the higher the water film was on the surface the smaller the width of the crown was.

Effect of Soil Moisture Content on the Splash Phenomenon Reproducibility

PubMed Central

Ryżak, Magdalena; Bieganowski, Andrzej; Polakowski, Cezary

2015-01-01

One of the methods for testing splash (the first phase of water erosion) may be an analysis of photos taken using so-called high-speed cameras. The aim of this study was to determine the reproducibility of measurements using a single drop splash of simulated precipitation. The height from which the drops fell resulted in a splash of 1.5 m. Tests were carried out using two types of soil: Eutric Cambisol (loamy silt) and Orthic Luvisol (sandy loam); three initial pressure heads were applied equal to 16 kPa, 3.1 kPa, and 0.1 kPa. Images for one, five, and 10 drops were recorded at a rate of 2000 frames per second. It was found that (i) the dispersion of soil caused by the striking of the 1st drop was significantly different from the splash impact caused by subsequent drops; (ii) with every drop, the splash phenomenon proceeded more reproducibly, that is, the number of particles of soil and/or water that splashed were increasingly close to each other; (iii) the number of particles that were detached during the splash were strongly correlated with its surface area; and (iv) the higher the water film was on the surface the smaller the width of the crown was. PMID:25785859

Viscoelastic drops moving on hydrophilic and superhydrophobic surfaces.

PubMed

Xu, H; Clarke, A; Rothstein, J P; Poole, R J

2018-03-01

So-called "superhydrophobic" surfaces are strongly non-wetting such that fluid droplets very easily roll off when the surface is tilted. Our interest here is in understanding if this is also true, all else held equal, for viscoelastic fluid drops. We study the movement of Newtonian and well-characterised constant-viscosity elastic liquids when various surfaces, including hydrophilic (smooth glass), weakly hydrophobic (embossed polycarbonate) and superhydrophobic surfaces (embossed PTFE), are impulsively tilted. Digital imaging is used to record the motion and extract drop velocity. Optical and SEM imaging is used to probe the surfaces. In comparison with "equivalent" Newtonian fluids (same viscosity, density surface tension and contact angles), profound differences for the elastic fluids are only observed on the superhydrophobic surfaces: the elastic drops slide at a significantly reduced rate and complex branch-like patterns are left on the surface by the drop's wake including, on various scales, beads-on-a-string-like phenomena. The strong viscoelastic effect is caused by stretching filaments of fluid from isolated islands, residing at pinning sites on the surface pillars, of order ∼30 µm in size. On this scale, the local strain rates are sufficient to extend the polymer chains, locally increasing the extensional viscosity of the solution, retarding the drop. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Ultrasonic Substrate Vibration-Assisted Drop Casting (SVADC) for the Fabrication of Photovoltaic Solar Cell Arrays and Thin-Film Devices.

PubMed

Eslamian, Morteza; Zabihi, Fatemeh

2015-12-01

A simple, low-cost, versatile, and potentially scalable casting method is proposed for the fabrication of micro- and nano-thin films, herein termed as ultrasonic "substrate vibration-assisted drop casting" (SVADC). The impingement of a solution drop onto a substrate in a simple process called drop casting, usually results in spreading of the liquid solution and the formation of a non-uniform thin solid film after solvent evaporation. Our previous and current supporting results, as well as few similar reports by others, confirm that imposing ultrasonic vibration on the substrate can simply convert the uncontrollable drop casting method into a controllable coating technique. Therefore, the SVADC may be used to fabricate an array of emerging thin-film solar cells, such as polymer, perovskite, and quantum-dot solar cells, as well as other small thin-film devices, in a roll-to-roll and automated fabrication process. The preliminary results demonstrate a ten-fold increase in electrical conductivity of PSS made by SVADC compared with the film made by conventional drop casting. Also, simple planar perovskite solar cells made here using SVADC show promising performance with an efficiency of over 3 % for a simple structure without performing process optimization or using expensive materials and treatments.

Controlling Droplet Impact with Polymer Additives

NASA Astrophysics Data System (ADS)

Smith, Michael; Bertola, Volfango

2012-02-01

When a water drop falls on to a hydrophobic surface, such as the waxy leaf of a plant, the drop often bounces off leading to wasted agrochemicals which harm the environment. However, adding small quantities (˜100 μgml-1) of a flexible polymer can completely prevent rebound. This is surprising since the shear viscosity and surface tension of such drops are almost identical to those of pure water. The effect has for some time been explained in terms of the stretching of polymer chains by a velocity gradient in the fluid, resulting in a transient increase in the so-called ``extensional viscosity.'' We have developed an epi-fluorescent microscope system, to visualise the flow of fluid inside an impacting drop using tracer particles at 2000 fps. Analysis of the velocity as a function of radius showed negligible differences between water and polymer drops except near the edge, indicating that the extensional viscosity cannot be responsible for the anti-rebound effect. To probe the true mechanism, fluorescently labelled ?-DNA was used to visualise the edge of an impacting drop. During the retraction phase, DNA was shown to be stretched by the retreating droplet providing an ``effective friction'' at the contact line. [4pt] [1] M.I Smith and V. Bertola, Phys. Rev. Letts. 104, 154502 (2010).

Estimating Lion Abundance using N-mixture Models for Social Species

PubMed Central

Belant, Jerrold L.; Bled, Florent; Wilton, Clay M.; Fyumagwa, Robert; Mwampeta, Stanslaus B.; Beyer, Dean E.

2016-01-01

Declining populations of large carnivores worldwide, and the complexities of managing human-carnivore conflicts, require accurate population estimates of large carnivores to promote their long-term persistence through well-informed management We used N-mixture models to estimate lion (Panthera leo) abundance from call-in and track surveys in southeastern Serengeti National Park, Tanzania. Because of potential habituation to broadcasted calls and social behavior, we developed a hierarchical observation process within the N-mixture model conditioning lion detectability on their group response to call-ins and individual detection probabilities. We estimated 270 lions (95% credible interval = 170–551) using call-ins but were unable to estimate lion abundance from track data. We found a weak negative relationship between predicted track density and predicted lion abundance from the call-in surveys. Luminosity was negatively correlated with individual detection probability during call-in surveys. Lion abundance and track density were influenced by landcover, but direction of the corresponding effects were undetermined. N-mixture models allowed us to incorporate multiple parameters (e.g., landcover, luminosity, observer effect) influencing lion abundance and probability of detection directly into abundance estimates. We suggest that N-mixture models employing a hierarchical observation process can be used to estimate abundance of other social, herding, and grouping species. PMID:27786283

Estimating Lion Abundance using N-mixture Models for Social Species.

PubMed

Belant, Jerrold L; Bled, Florent; Wilton, Clay M; Fyumagwa, Robert; Mwampeta, Stanslaus B; Beyer, Dean E

2016-10-27

Declining populations of large carnivores worldwide, and the complexities of managing human-carnivore conflicts, require accurate population estimates of large carnivores to promote their long-term persistence through well-informed management We used N-mixture models to estimate lion (Panthera leo) abundance from call-in and track surveys in southeastern Serengeti National Park, Tanzania. Because of potential habituation to broadcasted calls and social behavior, we developed a hierarchical observation process within the N-mixture model conditioning lion detectability on their group response to call-ins and individual detection probabilities. We estimated 270 lions (95% credible interval = 170-551) using call-ins but were unable to estimate lion abundance from track data. We found a weak negative relationship between predicted track density and predicted lion abundance from the call-in surveys. Luminosity was negatively correlated with individual detection probability during call-in surveys. Lion abundance and track density were influenced by landcover, but direction of the corresponding effects were undetermined. N-mixture models allowed us to incorporate multiple parameters (e.g., landcover, luminosity, observer effect) influencing lion abundance and probability of detection directly into abundance estimates. We suggest that N-mixture models employing a hierarchical observation process can be used to estimate abundance of other social, herding, and grouping species.

Drop Breakup in Fixed Bed Flows as Model Stochastic Flow Fields

NASA Technical Reports Server (NTRS)

Shaqfeh, Eric S. G.; Mosler, Alisa B.; Patel, Prateek

1999-01-01

We examine drop breakup in a class of stochastic flow fields as a model for the flow through fixed fiber beds and to elucidate the general mechanisms whereby drops breakup in disordered, Lagrangian unsteady flows. Our study consists of two parallel streams of investigation. First, large scale numerical simulations of drop breakup in a class of anisotropic Gaussian fields will be presented. These fields are generated spectrally and have been shown in a previous publication to be exact representations of the flow in a dilute disordered bed of fibers if close interactions between the fibers and the drops are dynamically unimportant. In these simulations the drop shape is represented by second and third order small deformation theories which have been shown to be excellent for the prediction of drop breakup in steady strong flows. We show via these simulations that the mechanisms of drop breakup in these flows are quite different than in steady flows. The predominant mechanism of breakup appears to be very short lived twist breakups. Moreover, the occurrence of breakup events is poorly predicted by either the strength of the local flow in which the drop finds itself at breakup, or the degree of deformation that the drop achieves prior to breakup. It is suggested that a correlation function of both is necessary to be predictive of breakup events. In the second part of our research experiments are presented where the drop deformation and breakup in PDMS/polyisobutylene emulsions is considered. We consider very dilute emulsions such that coalescence is unimportant. The flows considered are simple shear and the flow through fixed fiber beds. Turbidity, small angle light scattering, dichroism and microscopy are used to interrogate the drop deformation process in both flows. It is demonstrated that breakup at very low capillary numbers occurs in both flows but larger drop deformation occurs in the fixed bed flow. Moreover, it is witnessed that breakup in the bed occurs continuously during flow and apparently with uniform probability through the bed length. The drop deformations witnessed in our experiments are larger than those predicted by the numerical simulations, and future plans to investigate these differences are discussed.

Condition-dependent reproductive effort in frogs infected by a widespread pathogen

PubMed Central

Roznik, Elizabeth A.; Sapsford, Sarah J.; Pike, David A.; Schwarzkopf, Lin; Alford, Ross A.

2015-01-01

To minimize the negative effects of an infection on fitness, hosts can respond adaptively by altering their reproductive effort or by adjusting their timing of reproduction. We studied effects of the pathogenic fungus Batrachochytrium dendrobatidis on the probability of calling in a stream-breeding rainforest frog (Litoria rheocola). In uninfected frogs, calling probability was relatively constant across seasons and body conditions, but in infected frogs, calling probability differed among seasons (lowest in winter, highest in summer) and was strongly and positively related to body condition. Infected frogs in poor condition were up to 40% less likely to call than uninfected frogs, whereas infected frogs in good condition were up to 30% more likely to call than uninfected frogs. Our results suggest that frogs employed a pre-existing, plastic, life-history strategy in response to infection, which may have complex evolutionary implications. If infected males in good condition reproduce at rates equal to or greater than those of uninfected males, selection on factors affecting disease susceptibility may be minimal. However, because reproductive effort in infected males is positively related to body condition, there may be selection on mechanisms that limit the negative effects of infections on hosts. PMID:26063847

Calculating the weight of evidence in low-template forensic DNA casework.

PubMed

Lohmueller, Kirk E; Rudin, Norah

2013-01-01

Interpreting and assessing the weight of low-template DNA evidence presents a formidable challenge in forensic casework. This report describes a case in which a similar mixed DNA profile was obtained from four different bloodstains. The defense proposed that the low-level minor profile came from an alternate suspect, the defendant's mistress. The strength of the evidence was assessed using a probabilistic approach that employed likelihood ratios incorporating the probability of allelic drop-out. Logistic regression was used to model the probability of drop-out using empirical validation data from the government laboratory. The DNA profile obtained from the bloodstain described in this report is at least 47 billion times more likely if, in addition to the victim, the alternate suspect was the minor contributor, than if another unrelated individual was the minor contributor. This case illustrates the utility of the probabilistic approach for interpreting complex low-template DNA profiles. © 2012 American Academy of Forensic Sciences.

Method and system for conserving power in a telecommunications network during emergency situations

DOEpatents

Conrad, Stephen H [Algodones, NM; O'Reilly, Gerard P [Manalapan, NJ

2011-10-11

Disclosed is a method and apparatus for conserving power in a telecommunications network during emergency situations. A permissible number list of emergency and/or priority numbers is stored in the telecommunications network. In the event of an emergency or power failure, input digits of a call to the telecommunications network are compared to the permissible number list. The call is processed in the telecommunications network and routed to its destination if the input digits match an entry in the permissible number list. The call is dropped without any further processing if the input digits do not match an entry in the permissible number list. Thus, power can be conserved in emergency situations by only allowing emergency and/or priority calls.

Distributed Optimal Dispatch of Distributed Energy Resources Over Lossy Communication Networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Junfeng; Yang, Tao; Wu, Di

In this paper, we consider the economic dispatch problem (EDP), where a cost function that is assumed to be strictly convex is assigned to each of distributed energy resources (DERs), over packet dropping networks. The goal of a standard EDP is to minimize the total generation cost while meeting total demand and satisfying individual generator output limit. We propose a distributed algorithm for solving the EDP over networks. The proposed algorithm is resilient against packet drops over communication links. Under the assumption that the underlying communication network is strongly connected with a positive probability and the packet drops are independentmore » and identically distributed (i.i.d.), we show that the proposed algorithm is able to solve the EDP. Numerical simulation results are used to validate and illustrate the main results of the paper.« less

DNA commission of the International Society of Forensic Genetics: Recommendations on the evaluation of STR typing results that may include drop-out and/or drop-in using probabilistic methods

PubMed Central

Gill, P.; Gusmão, L.; Haned, H.; Mayr, W.R.; Morling, N.; Parson, W.; Prieto, L.; Prinz, M.; Schneider, H.; Schneider, P.M.; Weir, B.S.

2015-01-01

DNA profiling of biological material from scenes of crimes is often complicated because the amount of DNA is limited and the quality of the DNA may be compromised. Furthermore, the sensitivity of STR typing kits has been continuously improved to detect low level DNA traces. This may lead to (1) partial DNA profiles and (2) detection of additional alleles. There are two key phenomena to consider: allelic or locus ‘drop-out’, i.e. ‘missing’ alleles at one or more genetic loci, while ‘drop-in’ may explain alleles in the DNA profile that are additional to the assumed main contributor(s). The drop-in phenomenon is restricted to 1 or 2 alleles per profile. If multiple alleles are observed at more than two loci then these are considered as alleles from an extra contributor and analysis can proceed as a mixture of two or more contributors. Here, we give recommendations on how to estimate probabilities considering drop-out, Pr(D), and drop-in, Pr(C). For reasons of clarity, we have deliberately restricted the current recommendations considering drop-out and/or drop-in at only one locus. Furthermore, we offer recommendations on how to use Pr(D) and Pr(C) with the likelihood ratio principles that are generally recommended by the International Society of Forensic Genetics (ISFG) as measure of the weight of the evidence in forensic genetics. Examples of calculations are included. An Excel spreadsheet is provided so that scientists and laboratories may explore the models and input their own data. PMID:22864188

Physical constraints of cultural evolution of dialects in killer whales.

PubMed

Filatova, Olga A; Samarra, Filipa I P; Barrett-Lennard, Lance G; Miller, Patrick J O; Ford, John K B; Yurk, Harald; Matkin, Craig O; Hoyt, Erich

2016-11-01

Odontocete sounds are produced by two pairs of phonic lips situated in soft nares below the blowhole; the right pair is larger and is more likely to produce clicks, while the left pair is more likely to produce whistles. This has important implications for the cultural evolution of delphinid sounds: the greater the physical constraints, the greater the probability of random convergence. In this paper the authors examine the call structure of eight killer whale populations to identify structural constraints and to determine if they are consistent among all populations. Constraints were especially pronounced in two-voiced calls. In the calls of all eight populations, the lower component of two-voiced (biphonic) calls was typically centered below 4 kHz, while the upper component was typically above that value. The lower component of two-voiced calls had a narrower frequency range than single-voiced calls in all populations. This may be because some single-voiced calls are homologous to the lower component, while others are homologous to the higher component of two-voiced calls. Physical constraints on the call structure reduce the possible variation and increase the probability of random convergence, producing similar calls in different populations.

The effect of dropping height on jumping performance in trained and untrained prepubertal boys and girls.

PubMed

Bassa, Eleni I; Patikas, Dimitrios A; Panagiotidou, Aikaterini I; Papadopoulou, Sophia D; Pylianidis, Theofilos C; Kotzamanidis, Christos M

2012-08-01

Plyometric training in children, including different types of jumps, has become common practice during the last few years in different sports, although there is limited information about the adaptability of children with respect to different loads and the differences in performance between various jump types. The purpose of this study was to examine the effect of gender and training background on the optimal drop jump height of 9- to 11-year-old children. Sixty prepubertal (untrained and track and field athletes, boys and girls, equally distributed in each group [n = 15]), performed the following in random order: 3 squat jumps, 3 countermovement jumps (CMJs) and 3 drop jumps from heights of 10, 20, 30, 40, and 50 cm. The trial with the best performance in jump height of each test was used for further analysis. The jump type significantly affected the jump height. The jump height during the CMJ was the highest among all other jump types, resulting in advanced performance for both trained and untrained prepubertal boys and girls. However, increasing the dropping height did not change the jumping height or contact time during the drop jump. This possibly indicates an inability of prepubertal children to use their stored elastic energy to increase jumping height during drop jumps, irrespective of their gender or training status. This indicates that children, independent of gender and training status, have no performance gain during drop jumps from heights up to 50 cm, and therefore, it is recommended that only low drop jump heights be included in plyometric training to limit the probability of sustaining injuries.

The Effects of High-Altitude Electromagnetic Pulse (HEMP) on Telecommunications Assets

DTIC Science & Technology

1988-06-01

common to a whole class of switches. 5ESS switch software controls the operating system, call processing, and system administration andgmaintenance...LEVEL (ky/rn)3 (a). Mean Fraction of Preset Calls Dropped Due to Induced Transients3 1.0 W -o35kVhM (36 EVENTS) 5-40 kV/M (13 EVENTS) IAUTOMATIC ...eel PERIPHRAL UNIT BUS,IMNA The entire 4ESS system is controlled by the 1A processor. The processor monitors and controls the operation of the

Jetting from impact of a spherical drop with a deep layer

NASA Astrophysics Data System (ADS)

Zhang, Li; Toole, Jameson; Fazzaa, Kamel; Deegan, Robert; Deegan Group Team; X-Ray Science Division, Advanced Photon Source Collaboration

2011-11-01

We performed an experimental study of jets during the impact of a spherical drop with a deep layer of same liquid. Using high speed optical and X-ray imaging, we observe two types of jets: the so-called ejecta sheet which emerges almost immediately after impact and the lamella which emerges later. For high Reynolds number the two jets are distinct, while for low Reynolds number the two jets combine into a single continuous jet. We also measured the emergence time, speed, and position of the ejecta sheet and found simple scaling relations for these quantities.

Medical students' failure experiences and their related factors.

PubMed

Han, Eui Ryoung; Chung, Eun Kyung; Oh, Sun A; Chay, Kee Oh; Woo, Young Jong

2012-09-01

A considerable number of medical students drop out due to low academic achievement, and these students have a high probability of repeated failure experiences. This study investigated the personal and academic problems of these students to help develop student support systems. First-year (n=146) and second-year (n=119) medical students were asked to complete questionnaires. The questionnaires consisted of personality traits and the students' management of/satisfaction with school life. Students who had already dropped out accounted for 17.4% of the study subjects. The most common reason for dropping out was low academic achievement, and the most difficult part of taking a leave of absence from school was psychological anxiety. The group who dropped out had significantly lower levels of emotional stability, sociability, responsibility, dominance, masculinity, and superiority and more vulnerable mental states compared with those who did not drop out. They also expressed less motivation with regard to medical science and less satisfaction with school life than did the group that did not drop out. Those who dropped out tended not to prepare for exams, and they managed their time ineffectively. They also tried to resolve their difficulties alone and rarely sought help from teachers. More intimate student-teacher relationships should be established, and teachers should be encouraged to meet and interact with their students on a regular basis. Additionally, personality inventories should be used to assist in efforts to understand students, especially to identify hidden social and emotional problems.

CYCLAM - Recycling by a Laser-driven Drop Jet from Waste that Feeds AM

NASA Astrophysics Data System (ADS)

Kaplan, Alexander F. H.; Samarjy, Ramiz S. M.

Additive manufacturing of metal parts is supplied by powder or wire. Manufacturing of this raw material causes additional costs and environmental impact. A new technique is proposed where the feeding directly originates from a metal sheet, which can even be waste. When cutting is done by laser-induced boiling, melt is continuously ejected downwards underneath the sheet. The ejected melt is deposited as a track on a substrate, enabling additive manufacturing by substrate movement along a desired path. The melt first flows downwards as a column and after a few millimeters separates into drops, here about 500 micrometer in diameter, as observed by high speed imaging. The drops incorporate sequentially and calmly into a long melt pool on the substrate. While steel drops formed regular tracks on steel and aluminium substrates, on copper substrate periodic drops solidified instead. For this new technique, called CYCLAM, the laser beam acts indirectly while the drop jet becomes the main tool. From imaging, properties like the width or fluctuations of the drop jet can be statistically evaluated. Despite oscillation of the liquid column, the divergence of the drop jet remained small, improving the precision and robustness. The melt leaves the cut sheet as a liquid column, 1 to 4 mm in length, which periodically separates drops that are transferred as a liquid jet to the substrate. For very short distance of 2 to 3 mm between the two sheets this liquid column can transfer the melt continuously as a liquid bridge. This phenomenon was observed, as a variant of the technique, but the duration of the bridge was limited by fluid mechanic instabilities.

Nectar and pollination drops: how different are they?

PubMed

Nepi, Massimo; von Aderkas, Patrick; Wagner, Rebecca; Mugnaini, Serena; Coulter, Andrea; Pacini, Ettore

2009-08-01

Pollination drops and nectars (floral nectars) are secretions related to plant reproduction. The pollination drop is the landing site for the majority of gymnosperm pollen, whereas nectar of angiosperm flowers represents a common nutritional resource for a large variety of pollinators. Extrafloral nectars also are known from all vascular plants, although among the gymnosperms they are restricted to the Gnetales. Extrafloral nectars are not generally involved in reproduction but serve as 'reward' for ants defending plants against herbivores (indirect defence). Although very different in their task, nectars and pollination drops share some features, e.g. basic chemical composition and eventual consumption by animals. This has led some authors to call these secretions collectively nectar. Modern techniques that permit chemical analysis and protein characterization have very recently added important information about these sugary secretions that appear to be much more than a 'reward' for pollinating (floral nectar) and defending animals (extrafloral nectar) or a landing site for pollen (pollination drop). Nectar and pollination drops contain sugars as the main components, but the total concentration and the relative proportions are different. They also contain amino acids, of which proline is frequently the most abundant. Proteomic studies have revealed the presence of common functional classes of proteins such as invertases and defence-related proteins in nectar (floral and extrafloral) and pollination drops. Invertases allow for dynamic rearrangement of sugar composition following secretion. Defence-related proteins provide protection from invasion by fungi and bacteria. Currently, only few species have been studied in any depth. The chemical composition of the pollination drop must be investigated in a larger number of species if eventual phylogenetic relationships are to be revealed. Much more information can be provided from further proteomic studies of both nectar and pollination drop that will contribute to the study of plant reproduction and evolution.

Drop rebound after impact: the role of the receding contact angle.

PubMed

Antonini, C; Villa, F; Bernagozzi, I; Amirfazli, A; Marengo, M

2013-12-31

Data from the literature suggest that the rebound of a drop from a surface can be achieved when the wettability is low, i.e., when contact angles, measured at the triple line (solid-liquid-air), are high. However, no clear criterion exists to predict when a drop will rebound from a surface and which is the key wetting parameter to govern drop rebound (e.g., the "equilibrium" contact angle, θeq, the advancing and the receding contact angles, θA and θR, respectively, the contact angle hysteresis, Δθ, or any combination of these parameters). To clarify the conditions for drop rebound, we conducted experimental tests on different dry solid surfaces with variable wettability, from hydrophobic to superhydrophobic surfaces, with advancing contact angles 108° < θA < 169° and receding contact angles 89° < θR < 161°. It was found that the receding contact angle is the key wetting parameter that influences drop rebound, along with surface hydrophobicity: for the investigated impact conditions (drop diameter 2.4 < D0 < 2.6 mm, impact speed 0.8 < V < 4.1 m/s, Weber number 25 < We < 585), rebound was observed only on surfaces with receding contact angles higher than 100°. Also, the drop rebound time decreased by increasing the receding contact angle. It was also shown that in general care must be taken when using statically defined wetting parameters (such as advancing and receding contact angles) to predict the dynamic behavior of a liquid on a solid surface because the dynamics of the phenomenon may affect surface wetting close to the impact point (e.g., as a result of the transition from the Cassie-Baxter to Wenzel state in the case of the so-called superhydrophobic surfaces) and thus affect the drop rebound.

Virtual prototyping of drop test using explicit analysis

NASA Astrophysics Data System (ADS)

Todorov, Georgi; Kamberov, Konstantin

2017-12-01

Increased requirements for reliability and safety, included in contemporary standards and norms, has high impact over new product development. New numerical techniques based on virtual prototyping technology, facilitates imrpoving product development cycle, resutling in reduced time/money spent for this stage as well as increased knowledge about certain failure mechanism. So called "drop test" became nearly a "must" step in development of any human operated product. This study aims to demonstrate dynamic behaviour assessment of a structure under impact loads, based on virtual prototyping using a typical nonlinear analysis - explicit dynamics. An example is presneted, based on a plastic container that is used as cartridge for a dispenser machine exposed to various work conditions. Different drop orientations were analyzed and critical load cases and design weaknesses have been found. Several design modifications have been proposed, based on detailed analyses results review.

Bromfenac Ophthalmic

MedlinePlus

... minutes after using the medication to replace your lenses.tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding.You should know that bromfenac eye drops may slow healing of the eye after surgery. Call your doctor right away if your pain and swelling do not improve.

Close Calls

ERIC Educational Resources Information Center

Erickson, Paul

2010-01-01

As student enrollment drops, school districts need less learning space and fewer facilities. With cuts in funding, budgets cannot sustain existing building operations and program costs, and buildings must be taken offline or repurposed for financial efficiency. How does a community address this issue? Whether a district is having to shutter…

Red-shouldered hawk occupancy surveys in central Minnesota, USA

USGS Publications Warehouse

Henneman, C.; McLeod, M.A.; Andersen, D.E.

2007-01-01

Forest-dwelling raptors are often difficult to detect because many species occur at low density or are secretive. Broadcasting conspecific vocalizations can increase the probability of detecting forest-dwelling raptors and has been shown to be an effective method for locating raptors and assessing their relative abundance. Recent advances in statistical techniques based on presence-absence data use probabilistic arguments to derive probability of detection when it is <1 and to provide a model and likelihood-based method for estimating proportion of sites occupied. We used these maximum-likelihood models with data from red-shouldered hawk (Buteo lineatus) call-broadcast surveys conducted in central Minnesota, USA, in 1994-1995 and 2004-2005. Our objectives were to obtain estimates of occupancy and detection probability 1) over multiple sampling seasons (yr), 2) incorporating within-season time-specific detection probabilities, 3) with call type and breeding stage included as covariates in models of probability of detection, and 4) with different sampling strategies. We visited individual survey locations 2-9 times per year, and estimates of both probability of detection (range = 0.28-0.54) and site occupancy (range = 0.81-0.97) varied among years. Detection probability was affected by inclusion of a within-season time-specific covariate, call type, and breeding stage. In 2004 and 2005 we used survey results to assess the effect that number of sample locations, double sampling, and discontinued sampling had on parameter estimates. We found that estimates of probability of detection and proportion of sites occupied were similar across different sampling strategies, and we suggest ways to reduce sampling effort in a monitoring program.

Characterization of drop aerodynamic fragmentation in the bag and sheet-thinning regimes by crossed-beam, two-view, digital in-line holography

DOE PAGES

Guildenbecher, Daniel R.; Gao, Jian; Chen, Jun; ...

2017-04-19

When a spherical liquid drop is subjected to a step change in relative gas velocity, aerodynamic forces lead to drop deformation and possible breakup into a number of secondary fragments. In order to investigate this flow, a digital in-line holography (DIH) diagnostic is proposed which enables rapid quantification of spatial statistics with limited experimental repetition. To overcome the high uncertainty in the depth direction experienced in previous applications of DIH, a crossed-beam, two-view configuration is introduced. With appropriate calibration, this diagnostic is shown to provide accurate quantification of fragment sizes, three-dimensional positions and three-component velocities in a large measurement volume.more » We apply these capabilities in order to investigate the aerodynamic breakup of drops at two non-dimensional Weber numbers, We, corresponding to the bag (We = 14) and sheet-thinning (We = 55) regimes. Ensemble average results show the evolution of fragment size and velocity statistics during the course of breakup. Our results indicate that mean fragment sizes increase throughout the course of breakup. For the bag breakup case, the evolution of a multi-mode fragment size probability density is observed. This is attributed to separate fragmentation mechanisms for the bag and rim structures. In contrast, for the sheet-thinning case, the fragment size probability density shows only one distinct peak indicating a single fragmentation mechanism. Compared to previous related investigations of this flow, many orders of magnitude more fragments are measured per condition, resulting in a significant improvement in data fidelity. For this reason, this experimental dataset is likely to provide new opportunities for detailed validation of analytic and computational models of this flow.« less

Insights from the pollination drop proteome and the ovule transcriptome of Cephalotaxus at the time of pollination drop production.

PubMed

Pirone-Davies, Cary; Prior, Natalie; von Aderkas, Patrick; Smith, Derek; Hardie, Darryl; Friedman, William E; Mathews, Sarah

2016-05-01

Many gymnosperms produce an ovular secretion, the pollination drop, during reproduction. The drops serve as a landing site for pollen, but also contain a suite of ions and organic compounds, including proteins, that suggests diverse roles for the drop during pollination. Proteins in the drops of species of Chamaecyparis, Juniperus, Taxus, Pseudotsuga, Ephedra and Welwitschia are thought to function in the conversion of sugars, defence against pathogens, and pollen growth and development. To better understand gymnosperm pollination biology, the pollination drop proteomes of pollination drops from two species of Cephalotaxus have been characterized and an ovular transcriptome for C. sinensis has been assembled. Mass spectrometry was used to identify proteins in the pollination drops of Cephalotaxus sinensis and C. koreana RNA-sequencing (RNA-Seq) was employed to assemble a transcriptome and identify transcripts present in the ovules of C. sinensis at the time of pollination drop production. About 30 proteins were detected in the pollination drops of both species. Many of these have been detected in the drops of other gymnosperms and probably function in defence, polysaccharide metabolism and pollen tube growth. Other proteins appear to be unique to Cephalotaxus, and their putative functions include starch and callose degradation, among others. Together, the proteins appear either to have been secreted into the drop or to occur there due to breakdown of ovular cells during drop production. Ovular transcripts represent a wide range of gene ontology categories, and some may be involved in drop formation, ovule development and pollen-ovule interactions. The proteome of Cephalotaxus pollination drops shares a number of components with those of other conifers and gnetophytes, including proteins for defence such as chitinases and for carbohydrate modification such as β-galactosidase. Proteins likely to be of intracellular origin, however, form a larger component of drops from Cephalotaxus than expected from studies of other conifers. This is consistent with the observation of nucellar breakdown during drop formation in Cephalotaxus The transcriptome data provide a framework for understanding multiple metabolic processes that occur within the ovule and the pollination drop just before fertilization. They reveal the deep conservation of WUSCHEL expression in ovules and raise questions about whether any of the S-locus transcripts in Cephalotaxus ovules might be involved in pollen-ovule recognition. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Assault frequency and preformation probability of the {alpha} emission process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, H. F.; Royer, G.; Li, J. Q.

2011-08-15

A study of the assault frequency and preformation factor of the {alpha}-decay description is performed from the experimental {alpha}-decay constant and the penetration probabilities calculated from the generalized liquid-drop model (GLDM) potential barriers. To determine the assault frequency a quantum-mechanical method using a harmonic oscillator is introduced and leads to values of around 10{sup 21} s{sup -1}, similar to the ones calculated within the classical method. The preformation probability is around 10{sup -1}-10{sup -2}. The results for even-even Po isotopes are discussed for illustration. While the assault frequency presents only a shallow minimum in the vicinity of the magic neutronmore » number 126, the preformation factor and mainly the penetrability probability diminish strongly around N=126.« less

Characteristic length of the knotting probability revisited

NASA Astrophysics Data System (ADS)

Uehara, Erica; Deguchi, Tetsuo

2015-09-01

We present a self-avoiding polygon (SAP) model for circular DNA in which the radius of impermeable cylindrical segments corresponds to the screening length of double-stranded DNA surrounded by counter ions. For the model we evaluate the probability for a generated SAP with N segments having a given knot K through simulation. We call it the knotting probability of a knot K with N segments for the SAP model. We show that when N is large the most significant factor in the knotting probability is given by the exponentially decaying part exp(-N/NK), where the estimates of parameter NK are consistent with the same value for all the different knots we investigated. We thus call it the characteristic length of the knotting probability. We give formulae expressing the characteristic length as a function of the cylindrical radius rex, i.e. the screening length of double-stranded DNA.

Micro-explosion of compound drops

NASA Astrophysics Data System (ADS)

Chen, Chun-Kuei; Lin, Ta-Hui

2014-08-01

Introducing water into spray combustion systems, by either water-in-oil emulsification or supplementary water injection, is one of the major techniques for combustion improvement and NOx reduction. Plentiful researches are available on combustion of water-in-oil emulsion fuel drops. The emulsified liquid is a heterogeneous mixture of immiscible liquids. One component forms the continuous phase and the other component forms the discrete phase. The discrete phase consists of globules of the one fluid that are suspended in the continuous phase fluid. Water-in-oil emulsions are commonly considered for combustion applications because emulsions can result in micro-explosion, thereby reducing the average drop diameter to enhance liquid vaporization, and suppressing the formation of soot and NOx. However, the water addition generally does not exceed about 20% for smooth engine operations[!, 21. The combustion characteristics and micro-explosion of emulsion drop were studied by many researchers. The micro-explosion of water in fuel emulsion drops was caused by very fast growth of superheated water vapor bubbles, its superheat limits must be lower than the boiling point temperature of the fuel. These bubbles were primarily governed by the pressure difference between the superheated vapor and the liquid, and by the inertia imparted to the liquid by the motion of the bubble surface[3 6 In this study, we used a coaxial nozzle to generation the multi-component drop. The different type of water-in-oil fuel drops called the compound drops. Unlike an emulsion drop, a compound drop consists of a water core and a fuel shell, which can originate from the phase separation of emulsion[7, 81 or a water drop colliding with a fuel drop[9, 101 Burning and micro-explosion of compound drops have been found to be distinct from those of emulsion drops[9-111 Wang et al.[9 , 101 studied the combustion characteristics of collision merged alkane-water drops. The merged drops appeared in adhesive and inserted manners. The drop ignition delay time increased with increasing water content. The average burning rate of alkane-water drops decreased with increasing water content. In the burning process, hexadecane-water drops exhibited flash vaporization or flame extinction. Heterogeneous explosion was occasionally observed in drops with trapped air bubbles. The air bubbles were assumed to be the nucleation points of the heterogeneous explosions. Chen and Lin[11 studied the characteristics of water-in-dodecane compound drop with different water content, diameter of drop and environmental oxygen concentration. The vaporization rate increased with increasing environmental oxygen concentration. The compound drops micro-exploded during the burning process in a random way. The number of micro-explosions was majorly influenced by drop diameter, followed by environmental oxygen concentration. Water content had a weaker effect on micro-explosion. As available literature and research results of compound drop burning are scarce, their combustion and micro-explosion behaviors are still poorly understood. In this regard, we changed the drop nature as compound drops to study their combustion characteristics and micro-explosion phenomena.

Effects of Responding to a Name and Group Call on Preschoolers' Compliance

ERIC Educational Resources Information Center

Beaulieu, Lauren; Hanley, Gregory P.; Roberson, Aleasha A.

2012-01-01

We assessed teacher-child relations with respect to children's name calls, instructions, and compliance in a preschool classroom. The most frequent consequence to a child's name being called was the provision of instructions. We also observed a higher probability of compliance when children attended to a name call. Next, we evaluated the effects…

Application of allflex conservation buffer in illumina genotyping.

PubMed

de Groot, M; Ras, T; van Haeringen, W A

2016-12-01

This experiment was designed to study if liquid conservation buffer used in the novel Tissue Sampling Technology (TST) from Allflex can be used for Illumina BeadChip genotyping. Ear punches were collected from 6 bovine samples, using both the Tissue Sampling Unit (TSU) as well as the Total Tagger Universal (TTU) collection system. The stability of the liquid conservation buffer was tested by genotyping samples on Illumina BeadChips, incubated at 0, 3, 15, 24, 48, 72, 168, 336, 720 h after sample collection. Additionally, a replenishment study was designed to test how often the liquid conservation buffer could be completely replenished before a significant call rate drop could be observed. Results from the stability study showed an average call rate of 0.993 for samples collected with the TSU system and 0.953 for samples collected with the TTU system, both exceeding the inclusion threshold call rate of 0.85. As an additional control, the identity of the individual animals was confirmed using the International Society of Animal Genetics (ISAG) recommended SNP panel. The replenishment study revealed a slight drop in the sample call rate after replenishing the conservation buffer for the fourth time for the TSU as well as the TTU samples. In routine analysis, this application allows for multiple experiments to be performed on the liquid conservation buffer, while maintaining the tissue samples for future use. The data collected in this study shows that the liquid conservation buffer used in the TST system can be used for Illumina BeadChip genotyping applications.

Molecular analyses of the principal components of response strength.

PubMed Central

Killeen, Peter R; Hall, Scott S; Reilly, Mark P; Kettle, Lauren C

2002-01-01

Killeen and Hall (2001) showed that a common factor called strength underlies the key dependent variables of response probability, latency, and rate, and that overall response rate is a good predictor of strength. In a search for the mechanisms that underlie those correlations, this article shows that (a) the probability of responding on a trial is a two-state Markov process; (b) latency and rate of responding can be described in terms of the probability and period of stochastic machines called clocked Bernoulli modules, and (c) one such machine, the refractory Poisson process, provides a functional relation between the probability of observing a response during any epoch and the rate of responding. This relation is one of proportionality at low rates and curvilinearity at higher rates. PMID:12216975

Tables of stark level transition probabilities and branching ratios in hydrogen-like atoms

NASA Technical Reports Server (NTRS)

Omidvar, K.

1980-01-01

The transition probabilities which are given in terms of n prime k prime and n k are tabulated. No additional summing or averaging is necessary. The electric quantum number k plays the role of the angular momentum quantum number l in the presence of an electric field. The branching ratios between stark levels are also tabulated. Necessary formulas for the transition probabilities and branching ratios are given. Symmetries are discussed and selection rules are given. Some disagreements for some branching ratios are found between the present calculation and the measurement of Mark and Wierl. The transition probability multiplied by the statistical weight of the initial state is called the static intensity J sub S, while the branching ratios are called the dynamic intensity J sub D.

A probabilistic Sperner's theorem, with applications to the problem of retrieving information from a data base

NASA Technical Reports Server (NTRS)

Baumert, L. D.; Mceliece, R. J.; Rodemich, E. R.; Rumsey, H., Jr.

1978-01-01

The design of an optimal merged keycode data base information retrieval system is detailed. A probability distribution of n-bit binary words that minimized false drops was developed for the case where the set of desired records was a subset of tagged records.

The Indo-Pacific Warm Pool: critical to world oceanography and world climate

NASA Astrophysics Data System (ADS)

De Deckker, Patrick

2016-12-01

The Indo-Pacific Warm Pool holds a unique place on the globe. It is a large area [>30 × 106 km2] that is characterised by permanent surface temperature >28 °C and is therefore called the `heat engine' of the globe. High convective clouds which can reach altitudes up to 15 km generate much latent heat in the process of convection and this area is therefore called the `steam engine' of the world. Seasonal and contrasting monsoonal activity over the region is the cause for a broad seasonal change of surface salinities, and since the area lies along the path of the Great Ocean Conveyor Belt, it is coined the `dilution' basin due to the high incidence of tropical rain and, away from the equator, tropical cyclones contribute to a significant drop in sea water salinity. Discussion about what may happen in the future of the Warm Pool under global warming is presented together with a description of the Warm Pool during the past, such as the Last Glacial Maximum when sea levels had dropped by ~125 m. A call for urgent monitoring of the IPWP area is justified on the grounds of the significance of this area for global oceanographic and climatological processes, but also because of the concerned threats to human population living there.

Maximizing detection probability of Wetland-dependent birds during point-count surveys in northwestern Florida

USGS Publications Warehouse

Nadeau, C.P.; Conway, C.J.; Smith, B.S.; Lewis, T.E.

2008-01-01

We conducted 262 call-broadcast point-count surveys (1-6 replicate surveys on each of 62 points) using standardized North American Marsh Bird Monitoring Protocols between 31 May and 7 July 2006 on St. Vincent National Wildlife Refuge, an island off the northwest coast of Florida. We conducted double-blind multiple-observer surveys, paired morning and evening surveys, and paired morning and night surveys to examine the influence of call-broadcast and time of day on detection probability. Observer detection probability for all species pooled was 75% and was similar between passive (69%) and call-broadcast (65%) periods. Detection probability was higher on morning than evening (t = 3.0, P = 0.030) or night (t = 3.4, P = 0.042) surveys when we pooled all species. Detection probability was higher (but not significant for all species) on morning compared to evening or night surveys for all five focal species detected on surveys: Least Bittern (Ixobrychus exilis), Clapper Rail (Rallus longirostris), Purple Gallinule (Porphyrula martinica), Common Moorhen (Gallinula chloropus), and American Coot (Fulica americana). We detected more Least Bitterns (t = 2.4, P = 0.064) and Common Moorhens (t = 2.8, P = 0.026) on morning than evening surveys, and more Clapper Rails (t = 5.1, P = 0.014) on morning than night surveys.

Semantic Importance Sampling for Statistical Model Checking

DTIC Science & Technology

2015-01-16

SMT calls while maintaining correctness. Finally, we implement SIS in a tool called osmosis and use it to verify a number of stochastic systems with...2 surveys related work. Section 3 presents background definitions and concepts. Section 4 presents SIS, and Section 5 presents our tool osmosis . In...which I∗M|=Φ(x) = 1. We do this by first randomly selecting a cube c from C∗ with uniform probability since each cube has equal probability 9 5. OSMOSIS

Laboratory-Tutorial Activities for Teaching Probability

ERIC Educational Resources Information Center

Wittmann, Michael C.; Morgan, Jeffrey T.; Feeley, Roger E.

2006-01-01

We report on the development of students' ideas of probability and probability density in a University of Maine laboratory-based general education physics course called "Intuitive Quantum Physics". Students in the course are generally math phobic with unfavorable expectations about the nature of physics and their ability to do it. We…

Competency Education Offers Promise and Peril for Students

ERIC Educational Resources Information Center

Ritterband, Vicki; Heller, Rafael

2015-01-01

Lindsay Unified School District (California) exemplifies the promise of competency education (or performance-based education, as it is called locally). Since beginning its transition to the model in 2009, discipline problems have sharply dropped, the school climate has dramatically improved (as measured by the California Healthy Kids Survey), and…

Evaluation of video detection systems, volume 1 : effects of configuration changes in the performance of video detection systems.

DOT National Transportation Integrated Search

2009-10-01

The effects of modifying the configuration of three video detection (VD) systems (Iteris, Autoscope, and Peek) : are evaluated in daytime and nighttime conditions. Four types of errors were used: false, missed, stuck-on, and : dropped calls. The thre...

Meeting the needs of the teen-age pregnant student: an in-school program that works.

PubMed

McAfee, M L; Geesey, M R

1984-10-01

The drop-out rate for pregnant students in the York (Pennsylvania) City School District is dramatically lower than the national average because the district recognized the need for meeting the unique problems of the pregnant student. In York, as in the rest of the nation, teen-age pregnancy was on the increase. Administrators of the district realized that a separately housed alternative education program would be too costly. In January 1979, the authors designed and implemented an in-school program called "Changing Roles." Five years later, that program has become an important factor in keeping the majority of pregnant students in school, at the same time, providing the girls the special information they need. In the 1982-83 school year, only 9.5% of the pregnant students dropped out of York City schools. This rate is far below the national drop-out rate of 80% to 90%.

Comparing kept appointment rates when calls are made by physicians versus behavior health technicians in inner city hospital: literature review and cost considerations.

PubMed

Agarin, Taghogho; Okorafor, Ejine; Kailasam, Vasanth; Agarin, Aniefiok; Philias, Willy; Garcia, Dianelys; Osuchukwu, Uzoma; Fluyah, Dimy; Iheagwara, Chinedu; Donovan, Dennis; Roberts, Carol; Singh, Deepika; Nnadi, Charles; Sharif, Zafar

2015-04-01

Dropping out of scheduled care leads to medication non adherence, increased morbidity, relapse and readmission rates. As part of a performance improvement project to increase attendance rates at our outpatient clinic, psychiatric residents and Behavioral Health Technicians made reminder telephone calls under similar circumstances. We compared follow up appointment rates in the two groups. Our analysis showed that there was no significant difference in the rates of kept appointment overall between the two groups. The important finding is physician time could be better spent in other patient care duties and reminder calls could be delegated to other health staff.

Forced Oscillations of Supported Drops

NASA Technical Reports Server (NTRS)

Wilkes, Edward D.; Basaran, Osman A.

1996-01-01

Oscillations of supported liquid drops are the subject of wide scientific interest, with applications in areas as diverse as liquid-liquid extraction, synthesis of ceramic powders, growing of pure crystals in low gravity, and measurement of dynamic surface tension. In this research, axisymmetric forced oscillations of arbitrary amplitude of viscous liquid drops of fixed volume which are pendant from or sessile on a rod with a fixed or moving contact line and surrounded by an inviscid ambient gas are induced by moving the rod in the vertical direction sinusiodally in time. In this paper, a preliminary report is made on the computational analysis of the oscillations of supported drops that have 'clean' interfaces and whose contact lines remain fixed throughout their motions. The relative importance of forcing to damping can be increased by either increasing the amplitude of rod motion A or Reynolds number Re. It is shown that as the ratio of forcing to damping rises, for drops starting from an initial rest state a sharp increase in deformation can occur when they are forced to oscillate in the vicinity of their resonance frequencies, indicating the incipience of hysteresis. However, it is also shown that the existence of a second stable limit cycle and the occurrence of hysteresis can be observed if the drop is subjected to a so-called frequency sweep, where the forcing frequency is first increased and then decreased over a suitable range. Because the change in drop deformation response is abrupt in the vicinity of the forcing frequencies where hysteresis occurs, it should be possible to exploit the phenomenon to accurately measure the viscosity and surface tension of the drop liquid.

Using Single Drop Microextraction for Headspace Analysis with Gas Chromatography

NASA Astrophysics Data System (ADS)

Riccio, Daniel; Wood, Derrick C.; Miller, James M.

2008-07-01

Headspace (HS) gas chromatography (GC) is commonly used to analyze samples that contain non-volatiles. In 1996, a new sampling technique called single drop microextraction, SDME, was introduced, and in 2001 it was applied to HS analysis. It is a simple technique that uses equipment normally found in the undergraduate laboratory, making it ideal for instructional use, especially to illustrate HS analysis or as an alternative to solid-phase microextraction (SPME) to which it is very similar. The basic principles and practice of HS-GC using SDME are described, including a complete review of the literature. Some possible experiments are suggested using water and N -methylpyrrolidone (NMP) as solvents.

Changes in ethylene signaling and MADS box gene expression are associated with banana finger drop.

PubMed

Hubert, O; Piral, G; Galas, C; Baurens, F-C; Mbéguié-A-Mbéguié, D

2014-06-01

Banana finger drop was examined in ripening banana harvested at immature (iMG), early (eMG) and late mature green (lMG) stages, with contrasting ripening rates and ethylene sensitivities. Concomitantly, 11 ethylene signal transduction components (ESTC) and 6 MADS box gene expressions were comparatively studied in median (control zone, CZ) and pedicel rupture (drop zone DZ) areas in peel tissue. iMG fruit did not ripen or develop finger drop while eMG and lMG fruits displayed a similar finger drop pattern. Several ESTC and MADS box gene mRNAs were differentially induced in DZ and CZ and sequentially in eMG and lMG fruits. MaESR2, 3 and MaEIL1, MaMADS2 and MaMADS5 had a higher mRNA level in eMG and acted earlier, whereas MaERS1, MaCTR1, MaEIL3/AB266319, MaEIL4/AB266320 and MaEIL5/AB266321, MaMADS4 and to a lesser extent MaMADS2 and 5 acted later in lMG. In this fruit, MaERS1 and 3, MaCTR1, MaEIL3, 4 and MaEIL5/AB266321, and MaMADS4 were enhanced by finger drop, suggesting their specific involvement in this process. MaEIL1, MaMADS1 and 3, induced at comparable levels in DZ and CZ, are probably related to the overall fruit ripening process. These findings led us to consider that developmental cues are the predominant finger drop regulation factor. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Probability of detecting band-tailed pigeons during call-broadcast versus auditory surveys

USGS Publications Warehouse

Kirkpatrick, C.; Conway, C.J.; Hughes, K.M.; Devos, J.C.

2007-01-01

Estimates of population trend for the interior subspecies of band-tailed pigeon (Patagioenas fasciata fasciata) are not available because no standardized survey method exists for monitoring the interior subspecies. We evaluated 2 potential band-tailed pigeon survey methods (auditory and call-broadcast surveys) from 2002 to 2004 in 5 mountain ranges in southern Arizona, USA, and in mixed-conifer forest throughout the state. Both auditory and call-broadcast surveys produced low numbers of cooing pigeons detected per survey route (x?? ??? 0.67) and had relatively high temporal variance in average number of cooing pigeons detected during replicate surveys (CV ??? 161%). However, compared to auditory surveys, use of call-broadcast increased 1) the percentage of replicate surveys on which ???1 cooing pigeon was detected by an average of 16%, and 2) the number of cooing pigeons detected per survey route by an average of 29%, with this difference being greatest during the first 45 minutes of the morning survey period. Moreover, probability of detecting a cooing pigeon was 27% greater during call-broadcast (0.80) versus auditory (0.63) surveys. We found that cooing pigeons were most common in mixed-conifer forest in southern Arizona and density of male pigeons in mixed-conifer forest throughout the state averaged 0.004 (SE = 0.001) pigeons/ha. Our results are the first to show that call-broadcast increases the probability of detecting band-tailed pigeons (or any species of Columbidae) during surveys. Call-broadcast surveys may provide a useful method for monitoring populations of the interior subspecies of band-tailed pigeon in areas where other survey methods are inappropriate.

Fine-tuned echolocation and capture-flight of Myotis capaccinii when facing different-sized insect and fish prey.

PubMed

Aizpurua, Ostaizka; Aihartza, Joxerra; Alberdi, Antton; Baagøe, Hans J; Garin, Inazio

2014-09-15

Formerly thought to be a strictly insectivorous trawling bat, recent studies have shown that Myotis capaccinii also preys on fish. To determine whether differences exist in bat flight behaviour, prey handling and echolocation characteristics when catching fish and insects of different size, we conducted a field experiment focused on the last stage of prey capture. We used synchronized video and ultrasound recordings to measure several flight and dip features as well as echolocation characteristics, focusing on terminal buzz phase I, characterized by a call rate exceeding 100 Hz, and buzz phase II, characterized by a drop in the fundamental well below 20 kHz and a repetition rate exceeding 150 Hz. When capturing insects, bats used both parts of the terminal phase to the same extent, and performed short and superficial drags on the water surface. In contrast, when preying on fish, buzz I was longer and buzz II shorter, and the bats made longer and deeper dips. These variations suggest that lengthening buzz I and shortening buzz II when fishing is beneficial, probably because buzz I gives better discrimination ability and the broader sonar beam provided by buzz II is useless when no evasive flight of the prey is expected. Additionally, bats continued emitting calls beyond the theoretical signal-overlap zone, suggesting that they might obtain information even when they have surpassed that threshold, at least initially. This study shows that M. capaccinii can regulate the temporal components of its feeding buzzes and modify prey capture technique according to the target. © 2014. Published by The Company of Biologists Ltd.

Maximum drop radius and critical Weber number for splashing in the dynamical Leidenfrost regime

NASA Astrophysics Data System (ADS)

Riboux, Guillaume; Gordillo, Jose Manuel

2015-11-01

At room temperature, when a drop impacts against a smooth solid surface at a velocity above the so called critical velocity for splashing, the drop loses its integrity and fragments into tiny droplets violently ejected radially outwards. Below this critical velocity, the drop simply spreads over the substrate. Splashing is also reported to occur for solid substrate temperatures above the Leidenfrost temperature, T, for which a vapor layer prevents the drop from touching the substrate. In this case, the splashing morphology largely differs from the one reported at room temperature because, thanks to the presence of the gas layer, the shear stresses on the liquid do not decelerate the ejected lamella. Our purpose here is to predict, for wall temperatures above T, the dependence of the critical impact velocity on the temperature of the substrate as well as the maximum spreading radius for impacting velocities below the critical velocity for splashing. This is done making use of boundary integral simulations, where the velocity and the height of the liquid layer at the root of the ejected lamella are calculated numerically. This information constitutes the initial conditions for the one dimensional mass and momentum equations governing the dynamics of the toroidal rim limiting the edge of the lamella.

Interspecific variation in the phenology of advertisement calling in a temperate Australian frog community.

PubMed

Heard, Geoffrey W; Canessa, Stefano; Parris, Kirsten M

2015-09-01

Spatial and temporal partitioning of resources underlies the coexistence of species with similar niches. In communities of frogs and toads, the phenology of advertisement calling provides insights into temporal partitioning of reproductive effort and its implications for community dynamics. This study assessed the phenology of advertisement calling in an anuran community from Melbourne, in southern Australia. We collated data from 1432 surveys of 253 sites and used logistic regression to quantify seasonality in the nightly probability of calling and the influence of meteorological variables on this probability for six species of frogs. We found limited overlap in the predicted seasonal peaks of calling among these species. Those shown to have overlapping calling peaks are unlikely to be in direct competition, due to differences in larval ecology (Crinia signifera and Litoria ewingii) or differences in calling behavior and acoustics (Limnodynastes dumerilii and Litoria raniformis). In contrast, closely related and ecologically similar species (Crinia signfera and Crinia parinsignifera;Litoria ewingii and Litoria verreauxii) appear to have staggered seasonal peaks of calling. In combination with interspecific variation in the meteorological correlates of calling, these results may be indicative of temporal partitioning of reproductive activity to facilitate coexistence, as has been reported for tropical and temperate anurans from other parts of the globe.

Loneliness and Depression among Polish University Students: Preliminary Findings from a Longitudinal Study

ERIC Educational Resources Information Center

Grygiel, Pawel; Switaj, Piotr; Anczewska, Marta; Humenny, Grzegorz; Rebisz, Slawomir; Sikorska, Justyna

2013-01-01

It is widely acknowledged that loneliness and depression are prevalent among university students and may contribute to poor academic achievements or higher probability of dropping out of university. However, the associations between these two phenomena are complex and not fully understood. In this paper we describe preliminary findings from a…

Dropping in on the Math of Plinko

ERIC Educational Resources Information Center

Naresh, Nirmala; Royce, Bridget

2013-01-01

The game of Plinko offers students an exciting real-world example of the applications of probability and data analysis. The Common Core State Standards for Mathematics (CCSSI 2010) and the Guidelines for Assessment in Statistics Education (GAISE) (Franklin et al. 2007) suggest that students in grades 6-8 be given ample opportunities to engage in…

Mental Health and Education Decisions. CEE DP 136

ERIC Educational Resources Information Center

Cornaglia, Francesca; Crivellaro, Elena; McNally, Sandra

2012-01-01

Mental health problems--and depression in particular--have been rising internationally. The link between poor mental health and poor educational outcomes is particularly interesting in the case of the UK which has a low international ranking both on measures of child wellbeing and the probability of early drop-out from the labour market and…

Moisture Content Influences Ignitability of Slash Pine Litter

Treesearch

Winfred H. Blackmarr

1972-01-01

The influence of moisture content on the ignitability of slash pine litter was measured by dropping lighted matches onto fuel beds conditioned to different levels of moisture content.The percentage of matches igniting the fuel bed was used to indicate ignition probability at each moisture content. The "critical range" of fuel moisture contents within which...

A Meteorite Dropping Superbolide from the Catastrophycally Disrupted Comet C1919Q2 Metcalf: A Pathway for Meteorites from Jupiter Family Comets

NASA Astrophysics Data System (ADS)

Trigo-Rodríguez, J. M.; Madiedo, J. M.; Williams, I. P.; Castro-Tirado, A. J.; Llorca, J.; Vítek, S.; Jelínek, M.

2009-03-01

A meter-sized meteoroid probably produced during the disintegration of comet C1919Q2 Metcalf was observed producing a -18 magn. bolide (MNRAS, in press).The progenitor meteoroid was sufficiently large and of high enough tensile strength to produce meteorites.

Why Subscribers Drop Cable Television: Characteristics of Three Groups.

ERIC Educational Resources Information Center

Burkum, Larry G.; Niebauer, Walter E., Jr.

It would be to the advantage of cable operators to identify, in advance, those subscribers who have a high probability of voluntarily disconnecting their service, in order to develop strategies to anticipate and address the factors that might potentially lead to disconnection. A study developed a method for identifying likely disconnecters.…

Reduction of enhanced rabbit intraocular pressure by instillation of pyroglutamic acid eye drops.

PubMed

Ito, Yoshimasa; Nagai, Noriaki; Okamoto, Norio; Shimomura, Yoshikazu; Nakanishi, Kunio; Tanaka, Ryuichiro

2013-01-01

L-Pyroglutamic acid (PGA) is an endogenous molecule derived from l-glutamate. We demonstrate the effects of PGA on intraocular pressure (IOP) in experimentally induced ocular hypertension in rabbits. In the in vitro and in vivo transcorneal penetration studies, the PGA solution (PGA in saline) did not penetrate the rabbit cornea. On the other hand, the penetration of PGA was improved by the addition of zinc chloride and 2-hydroxypropyl-β-cyclodextrin (HPCD), and PGA penetration was enhanced with increasing HPCD concentration. Therefore, PGA solutions containing 0.5% zinc chloride and 5% or 10% HPCD (PGA/HPCD(5% or 10%) eye drops) were used to investigate the effects for IOP in this study. An elevation in IOP was induced by the rapid infusion of 5% glucose solution (15 mL/kg of body weight) through the marginal ear vein or maintaining under dark phase for 5 h. In the both models, the induced elevation in IOP was prevented by the instillation of PGA/HPCD eye drops, and the IOP-reducing effect enhanced with increasing HPCD concentration in the drops. Nitric oxide (NO) levels elevated in the aqueous humor following the infusion of 5% glucose solution, and this increase was also suppressed by the instillation of PGA/HPCD eye drops. In conclusion, the present study demonstrates that the instillation of PGA/HPCD eye drops has an IOP-reducing effect in rabbits with experimentally induced ocular hypertension, probably as a result of the suppression of NO production.

Cetacean population density estimation from single fixed sensors using passive acoustics.

PubMed

Küsel, Elizabeth T; Mellinger, David K; Thomas, Len; Marques, Tiago A; Moretti, David; Ward, Jessica

2011-06-01

Passive acoustic methods are increasingly being used to estimate animal population density. Most density estimation methods are based on estimates of the probability of detecting calls as functions of distance. Typically these are obtained using receivers capable of localizing calls or from studies of tagged animals. However, both approaches are expensive to implement. The approach described here uses a MonteCarlo model to estimate the probability of detecting calls from single sensors. The passive sonar equation is used to predict signal-to-noise ratios (SNRs) of received clicks, which are then combined with a detector characterization that predicts probability of detection as a function of SNR. Input distributions for source level, beam pattern, and whale depth are obtained from the literature. Acoustic propagation modeling is used to estimate transmission loss. Other inputs for density estimation are call rate, obtained from the literature, and false positive rate, obtained from manual analysis of a data sample. The method is applied to estimate density of Blainville's beaked whales over a 6-day period around a single hydrophone located in the Tongue of the Ocean, Bahamas. Results are consistent with those from previous analyses, which use additional tag data. © 2011 Acoustical Society of America

An efficient algorithm to compute marginal posterior genotype probabilities for every member of a pedigree with loops

PubMed Central

2009-01-01

Background Marginal posterior genotype probabilities need to be computed for genetic analyses such as geneticcounseling in humans and selective breeding in animal and plant species. Methods In this paper, we describe a peeling based, deterministic, exact algorithm to compute efficiently genotype probabilities for every member of a pedigree with loops without recourse to junction-tree methods from graph theory. The efficiency in computing the likelihood by peeling comes from storing intermediate results in multidimensional tables called cutsets. Computing marginal genotype probabilities for individual i requires recomputing the likelihood for each of the possible genotypes of individual i. This can be done efficiently by storing intermediate results in two types of cutsets called anterior and posterior cutsets and reusing these intermediate results to compute the likelihood. Examples A small example is used to illustrate the theoretical concepts discussed in this paper, and marginal genotype probabilities are computed at a monogenic disease locus for every member in a real cattle pedigree. PMID:19958551

Our Time: The Legacy of the Twentieth Century

ERIC Educational Resources Information Center

Humphries, Tom

2014-01-01

We are probably only at the beginning of our understanding of a period of time that gave us a new name for an old language, "ASL," a new consciousness called "Deaf culture," a national uprising called "DPN," and a science fiction-like new technology called "VP." The two halves of the twentieth century might…

Two types of Cassie-to-Wenzel wetting transitions on superhydrophobic surfaces during drop impact.

PubMed

Lee, Choongyeop; Nam, Youngsuk; Lastakowski, Henri; Hur, Janet I; Shin, Seungwon; Biance, Anne-Laure; Pirat, Christophe; Kim, Chang-Jin C J; Ybert, Christophe

2015-06-21

Despite the fact that superhydrophobic surfaces possess useful and unique properties, their practical application has remained limited by durability issues. Among those, the wetting transition, whereby a surface gets impregnated by the liquid and permanently loses its superhydrophobicity, certainly constitutes the most limiting aspect under many realistic conditions. In this study, we revisit this so-called Cassie-to-Wenzel transition (CWT) under the broadly encountered situation of liquid drop impact. Using model hydrophobic micropillar surfaces of various geometrical characteristics and high speed imaging, we identify that CWT can occur through different mechanisms, and at different impact stages. At early impact stages, right after contact, CWT occurs through the well established dynamic pressure scenario of which we provide here a fully quantitative description. Comparing the critical wetting pressure of surfaces and the theoretical pressure distribution inside the liquid drop, we provide not only the CWT threshold but also the hardly reported wetted area which directly affects the surface spoiling. At a later stage, we report for the first time to our knowledge, a new CWT which occurs during the drop recoil toward bouncing. With the help of numerical simulations, we discuss the mechanism underlying this new transition and provide a simple model based on impulse conservation which successfully captures the transition threshold. By shedding light on the complex interaction between impacting water drops and surface structures, the present study will facilitate designing superhydrophobic surfaces with a desirable wetting state during drop impact.

Nectar and pollination drops: how different are they?

PubMed Central

Nepi, Massimo; von Aderkas, Patrick; Wagner, Rebecca; Mugnaini, Serena; Coulter, Andrea; Pacini, Ettore

2009-01-01

Background Pollination drops and nectars (floral nectars) are secretions related to plant reproduction. The pollination drop is the landing site for the majority of gymnosperm pollen, whereas nectar of angiosperm flowers represents a common nutritional resource for a large variety of pollinators. Extrafloral nectars also are known from all vascular plants, although among the gymnosperms they are restricted to the Gnetales. Extrafloral nectars are not generally involved in reproduction but serve as ‘reward’ for ants defending plants against herbivores (indirect defence). Scope Although very different in their task, nectars and pollination drops share some features, e.g. basic chemical composition and eventual consumption by animals. This has led some authors to call these secretions collectively nectar. Modern techniques that permit chemical analysis and protein characterization have very recently added important information about these sugary secretions that appear to be much more than a ‘reward’ for pollinating (floral nectar) and defending animals (extrafloral nectar) or a landing site for pollen (pollination drop). Conclusions Nectar and pollination drops contain sugars as the main components, but the total concentration and the relative proportions are different. They also contain amino acids, of which proline is frequently the most abundant. Proteomic studies have revealed the presence of common functional classes of proteins such as invertases and defence-related proteins in nectar (floral and extrafloral) and pollination drops. Invertases allow for dynamic rearrangement of sugar composition following secretion. Defence-related proteins provide protection from invasion by fungi and bacteria. Currently, only few species have been studied in any depth. The chemical composition of the pollination drop must be investigated in a larger number of species if eventual phylogenetic relationships are to be revealed. Much more information can be provided from further proteomic studies of both nectar and pollination drop that will contribute to the study of plant reproduction and evolution. PMID:19477895

Wireless Drop Tower for Microgravity Demonstrations. Educational Brief.

ERIC Educational Resources Information Center

National Aeronautics and Space Administration, Washington, DC.

Microgravity-the absence or reduction of some of the effects of gravity-is an important attribute of free-fall. In microgravity (often incorrectly called zero-g), water no longer flows "downhill" and neither do smoke or steam bubbles rise. This changes a number of chemical and physical activities. Experiments in combustion, fluid behavior,…

Beyond Stigmatization of Children with Difficulties in Learning

ERIC Educational Resources Information Center

Hido, Margarita; Shehu, Irena

2010-01-01

In the Albanian schools settings does not exist religious discrimination, neither gender discrimination, but there exists a discrimination, as unfair against children called "difficulty". The children who drop out of school are by far less numerous compared with those who start school, but who are not properly treated, so that they can…

Language and Knowing

ERIC Educational Resources Information Center

Cassuto, Leonard

2004-01-01

The author used to teach a core course at Fordham University called "Language and Knowing." It was during an evening meeting of that class early in 1991 that he first heard that "Operation Desert Storm" had begun-by which he means that the United States and its allies started dropping bombs on Iraq and occupied Kuwait in…

Simulations Help School Leaders Practice "Tough Conversations"

ERIC Educational Resources Information Center

Sparks, Sarah D.

2012-01-01

Jody F. Manning has been a superintendent in New York for more than 20 years, but his experience didn't make his conversation with the woman across the table any easier. "Terry Jones" had made three increasingly urgent phone calls asking to meet about her daughter, whose grades have been dropping precipitously. Jones talked about her…

Defense.gov Special Report: Travels With Carter - July 2015

Science.gov Websites

by Defense Secretary Ash Carter to the National Association of Counties Remarks by Defense Secretary Secretary Carter speaking at National Association Counties Conference Carter Calls on Community Leaders to Paratroopers Demonstrate Air Drop on Fort Bragg Photo Essay Carter Speaks at National Association of Counties

Effect of introduction of electronic patient reporting on the duration of ambulance calls.

PubMed

Kuisma, Markku; Väyrynen, Taneli; Hiltunen, Tuomas; Porthan, Kari; Aaltonen, Janne

2009-10-01

We examined the effect of the change from paper records to the electronic patient records (EPRs) on ambulance call duration. We retrieved call duration times 6 months before (group 1) and 6 months after (group 2) the introduction of EPR. Subgroup analysis of group 2 was fulfilled depending whether the calls were made during the first or last 3 months after EPR introduction. We analyzed 37 599 ambulance calls (17 950 were in group 1 and 19 649 were in group 2). The median call duration in group 1 was 48 minutes and in group 2 was 49 minutes (P = .008). In group 2, call duration was longer during the first 3 months after EPR introduction. In multiple linear regression analysis, urgency category (P < .0001), unit level (P < .0001), and transportation decision (P < .0001) influenced the call duration. The documentation method was not a significant factor. Electronic patient record system can be implemented in an urban ambulance service in such a way that documentation method does not become a significant factor in determining call duration in the long run. Temporary performance drop during the first 3 months after introduction was noticed, reflecting adaptation process to a new way of working.

High stress shallow moonquakes - Evidence for an initially totally molten moon

NASA Technical Reports Server (NTRS)

Binder, A. B.; Oberst, J.

1985-01-01

Thermoelastic stress calculations show that if the moon was initially molten only in the outer few hundred kilometers, as in the magma ocean model of the moon, the highlands crust should be aseismic. In contrast, if the moon was initially totally molten, high stress (1 to more than about 3 kbar), shallow (0 to about 6 km deep), compressional moonquakes should be occurring in the highlands crust. Calculations of the minimum stress drops made for the 28 observed shallow moonquakes suggest that 3 of them probably have stress drops in the kbar range. Thus, these very limited seismic data are consistent with the model that the moon was initially totally molten.

Translational velocity oscillations of piston generated vortex rings

NASA Astrophysics Data System (ADS)

Kumar, Manoj; Arakeri, J. H.; Shankar, P. N.

1995-11-01

Experimental results are presented that show that the translational velocities of piston generated vortex rings often undergo oscillations, similar to those recently discovered for drop generated rings. An attempt has been made to minimize uncertainties by utilizing both dye and hydrogen bubbles for visualization and carefully repeating measurements on the same ring and on different realizations under the same nominal piston conditions. The results unambiguously show that under most conditions, both for laminar and turbulent rings and for rings generated from pipes and orifices, the oscillations are present. The present results, together with the earlier results on drop generated rings, give support to the view that translational velocity oscillations are probably an inherent feature of translating vortex ring fields.

Stochastic growth of cloud droplets by collisions during settling

NASA Astrophysics Data System (ADS)

Madival, Deepak G.

2018-04-01

In the last stage of droplet growth in clouds which leads to drizzle formation, larger droplets begin to settle under gravity and collide and coalesce with smaller droplets in their path. In this article, we shall deal with the simplified problem of a large drop settling amidst a population of identical smaller droplets. We present an expression for the probability that a given large drop suffers a given number of collisions, for a general statistically homogeneous distribution of droplets. We hope that our approach will serve as a valuable tool in dealing with droplet distribution in real clouds, which has been found to deviate from the idealized Poisson distribution due to mechanisms such as inertial clustering.

[Analysis of core virion polypeptides from the pathogen causing chicken egg-drop syndrome].

PubMed

Iurov, G K; Dadykov, V A; Neugodova, G L; Naroditskiĭ, B S

1998-01-01

The cores of egg-drop syndrome virus (EDS-76) were isolated by the pyridine technique. EDS-76 proved to be much more resistant to pyridine disruption than other adenoviruses and treatment with 10% pyridine did not lead to complete dissociation of capsid and cores; only increase of pyridine concentration to 20% produced satisfactory results. At least three polypeptides (24, 10.5, and 6.5 kDa) were found in the core by SDS-PAGE, whereas the 40 kDa reacting with the core is most probably not a core component. Much more intensive reactions of the core with EDS-76 virion capsid suggest that its virion structure differs from that of other adenoviruses.

An Empirical Method Permitting Rapid Determination of the Area, Rate and Distribution of Water-Drop Impingement on an Airfoil of Arbitrary Section at Subsonic Speeds

NASA Technical Reports Server (NTRS)

Bergrun, N. R.

1951-01-01

An empirical method for the determination of the area, rate, and distribution of water-drop impingement on airfoils of arbitrary section is presented. The procedure represents an initial step toward the development of a method which is generally applicable in the design of thermal ice-prevention equipment for airplane wing and tail surfaces. Results given by the proposed empirical method are expected to be sufficiently accurate for the purpose of heated-wing design, and can be obtained from a few numerical computations once the velocity distribution over the airfoil has been determined. The empirical method presented for incompressible flow is based on results of extensive water-drop. trajectory computations for five airfoil cases which consisted of 15-percent-thick airfoils encompassing a moderate lift-coefficient range. The differential equations pertaining to the paths of the drops were solved by a differential analyzer. The method developed for incompressible flow is extended to the calculation of area and rate of impingement on straight wings in subsonic compressible flow to indicate the probable effects of compressibility for airfoils at low subsonic Mach numbers.

Break-up of droplets in a concentrated emulsion flowing through a narrow constriction

NASA Astrophysics Data System (ADS)

Kim, Minkyu; Rosenfeld, Liat; Tang, Sindy; Tang Lab Team

2014-11-01

Droplet microfluidics has enabled a wide range of high throughput screening applications. Compared with other technologies such as robotic screening technology, droplet microfluidics has 1000 times higher throughput, which makes the technology one of the most promising platforms for the ultrahigh throughput screening applications. Few studies have considered the throughput of the droplet interrogation process, however. In this research, we show that the probability of break-up increases with increasing flow rate, entrance angle to the constriction, and size of the drops. Since single drops do not break at the highest flow rate used in the system, break-ups occur primarily from the interactions between highly packed droplets close to each other. Moreover, the probabilistic nature of the break-up process arises from the stochastic variations in the packing configuration. Our results can be used to calculate the maximum throughput of the serial interrogation process. For 40 pL-drops, the highest throughput with less than 1% droplet break-up was measured to be approximately 7,000 drops per second. In addition, the results are useful for understanding the behavior of concentrated emulsions in applications such as mobility control in enhanced oil recovery.

Optimized Vertex Method and Hybrid Reliability

NASA Technical Reports Server (NTRS)

Smith, Steven A.; Krishnamurthy, T.; Mason, B. H.

2002-01-01

A method of calculating the fuzzy response of a system is presented. This method, called the Optimized Vertex Method (OVM), is based upon the vertex method but requires considerably fewer function evaluations. The method is demonstrated by calculating the response membership function of strain-energy release rate for a bonded joint with a crack. The possibility of failure of the bonded joint was determined over a range of loads. After completing the possibilistic analysis, the possibilistic (fuzzy) membership functions were transformed to probability density functions and the probability of failure of the bonded joint was calculated. This approach is called a possibility-based hybrid reliability assessment. The possibility and probability of failure are presented and compared to a Monte Carlo Simulation (MCS) of the bonded joint.

Behavioral predictors of attrition in adolescents participating in a multidisciplinary obesity treatment program: EVASYON study.

PubMed

De Miguel-Etayo, P; Muro, C; Santabárbara, J; López-Antón, R; Morandé, G; Martín-Matillas, M; Azcona-San Julián, M C; Martí, A; Campoy, C; Marcos, A; Moreno, L A; Garagorri, J M

2016-01-01

The aims of this study were to identify the cognitive and behavioral predictors of dropping out and to estimate the attrition rate during different phases of an intervention program to treat overweight and obesity in adolescents. Overweight/obese adolescents (n=156, aged: 13-16 years; 71 male and 85 female subjects) were included in a multicomponent (diet, physical activity and psychological support) family-based group treatment program. At baseline and after 2 months (intensive phase) and 13 months (extensive phase) of follow-up, we measured adolescents' cognitive and behavioral dimensions, together with the parents' perception of their child's behavior. Of the 156 adolescents selected, 112 completed the full program (drop-out rate of 28.2%). The risk of dropping out during the extensive phase increased by 20% for each unit increase in the adolescent's social insecurity score (odds ratio=1.20, 95% confidence interval=1.07-1.34, P=0.002). The adolescents who had a high interoceptive awareness showed a significant decrease of 13.0% in the probability of dropping out (odds ratio=0.87, 95% confidence interval=0.77-0.99, P=0.040). Adolescents' social insecurity was the main predictor of drop-out in a multicomponent family-group-based obesity treatment program. To reduce attrition rates in these programs, the individual's social insecurity level needs to be reduced, whereas the family's awareness of eating-related behavior needs adjustment.

Part 2 of a Computational Study of a Drop-Laden Mixing Layer

NASA Technical Reports Server (NTRS)

Okongo, Nora; Bellan, Josette

2004-01-01

This second of three reports on a computational study of a mixing layer laden with evaporating liquid drops presents the evaluation of Large Eddy Simulation (LES) models. The LES models were evaluated on an existing database that had been generated using Direct Numerical Simulation (DNS). The DNS method and the database are described in the first report of this series, Part 1 of a Computational Study of a Drop-Laden Mixing Layer (NPO-30719), NASA Tech Briefs, Vol. 28, No.7 (July 2004), page 59. The LES equations, which are derived by applying a spatial filter to the DNS set, govern the evolution of the larger scales of the flow and can therefore be solved on a coarser grid. Consistent with the reduction in grid points, the DNS drops would be represented by fewer drops, called computational drops in the LES context. The LES equations contain terms that cannot be directly computed on the coarser grid and that must instead be modeled. Two types of models are necessary: (1) those for the filtered source terms representing the effects of drops on the filtered flow field and (2) those for the sub-grid scale (SGS) fluxes arising from filtering the convective terms in the DNS equations. All of the filtered-sourceterm models that were developed were found to overestimate the filtered source terms. For modeling the SGS fluxes, constant-coefficient Smagorinsky, gradient, and scale-similarity models were assessed and calibrated on the DNS database. The Smagorinsky model correlated poorly with the SGS fluxes, whereas the gradient and scale-similarity models were well correlated with the SGS quantities that they represented.

Teachers' Understanding of Students' Attitudes and Values toward Physical Activity in Physical Education Dropout Rates and Adolescent Obesity

ERIC Educational Resources Information Center

Landolfi, Emilio

2014-01-01

Structured interviews were used to explore 10th grade teachers' understanding of students' attitudes and values toward physical education and physical activity as a variable in students' probability of dropping physical education and adolescent obesity. When asked how school-based physical education could help combat the problem of students…

What Causes Rainbows?

ERIC Educational Resources Information Center

Beck, John

2004-01-01

If one looks at a rain cloud with the Sun behind one's back, the sunlight and water drops may interact just right, revealing the familiar arc of red, orange, yellow, green, blue, indigo, and violet. Many of people have been pleasantly surprised to see a rainbow in the sky, but probably have not considered why they occur. Rainbows are caused by…

Avian Influenza Vaccination of Poultry and Passive Case Reporting, Egypt

PubMed Central

Grosbois, Vladimir; Jobre, Yilma; Saad, Ahmed; El Nabi, Amira Abd; Galal, Shereen; Kalifa, Mohamed; El Kader, Soheir Abd; Dauphin, Gwenaëlle; Roger, François; Lubroth, Juan; Peyre, Marisa

2012-01-01

We investigated the influence of a mass poultry vaccination campaign on passive surveillance of highly pathogenic avian influenza subtype (H5N1) outbreaks among poultry in Egypt. Passive reporting dropped during the campaign, although probability of infection remained unchanged. Future poultry vaccination campaigns should consider this negative impact on reporting for adapting surveillance strategies. PMID:23171740

Experimental and numerical study of drill bit drop tests on Kuru granite

NASA Astrophysics Data System (ADS)

Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko

2017-01-01

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

Measurement of thin liquid film drainage using a novel high-speed impedance analyzer

NASA Astrophysics Data System (ADS)

Hool, Kevin O.; Saunders, Robert C.; Ploehn, Harry J.

1998-09-01

This work describes the design and implementation of a new instrument, called the thin film impedance analyzer, which measures the rate of drainage of thin oil films. The instrument forms an oil film by elevating a planar oil-water interface into a water drop hanging from a stainless steel capillary tube immersed in the oil. The instrument measures the magnitude of the impedance of the matter between the capillary tube and a screen electrode immersed in the lower water phase. Under appropriate conditions, the capacitance of the oil film dominates the impedance. The instrument records the increase in the magnitude of the admittance associated with the draining and thinning of the oil film. The features of the drainage curves vary considerably with the type, amount, and location of surfactants in the oil and water phases, as well as with user-specified values of drop volume, drop equilibration time, and extent of drop compression. For this reason, the instrument has utility as a screening tool for selecting surfactants for emulsion formulations. Potential future uses include accelerated prediction of emulsion stability and extraction of oil-water interfacial rheological parameters.

Simple Physical Model for the Probability of a Subduction- Zone Earthquake Following Slow Slip Events and Earthquakes: Application to the Hikurangi Megathrust, New Zealand

NASA Astrophysics Data System (ADS)

Kaneko, Yoshihiro; Wallace, Laura M.; Hamling, Ian J.; Gerstenberger, Matthew C.

2018-05-01

Slow slip events (SSEs) have been documented in subduction zones worldwide, yet their implications for future earthquake occurrence are not well understood. Here we develop a relatively simple, simulation-based method for estimating the probability of megathrust earthquakes following tectonic events that induce any transient stress perturbations. This method has been applied to the locked Hikurangi megathrust (New Zealand) surrounded on all sides by the 2016 Kaikoura earthquake and SSEs. Our models indicate the annual probability of a M≥7.8 earthquake over 1 year after the Kaikoura earthquake increases by 1.3-18 times relative to the pre-Kaikoura probability, and the absolute probability is in the range of 0.6-7%. We find that probabilities of a large earthquake are mainly controlled by the ratio of the total stressing rate induced by all nearby tectonic sources to the mean stress drop of earthquakes. Our method can be applied to evaluate the potential for triggering a megathrust earthquake following SSEs in other subduction zones.

If you provide the test, they will take it: factors associated with HIV/STI Testing in a representative sample of homeless youth in Los Angeles.

PubMed

Ober, Allison J; Martino, Steven C; Ewing, Brett; Tucker, Joan S

2012-08-01

Homeless youth are at high risk for human immunodeficiency virus (HIV) and other sexually transmitted infections (STI), yet those at greatest risk may never have been tested for HIV or STI. In a probability sample of sexually active homeless youth in Los Angeles (n = 305), this study identifies factors associated with HIV/STI testing status. Most youth (85%) had ever been tested and 47% had been tested in the past 3 months. Recent testing was significantly more likely among youth who self-identified as gay, were Hispanic, injected drugs, and used drop-in centers, and marginally more likely among youth with more depressive symptoms. Drop-in center use mediated the association of injection drug use with HIV/STI testing. HIV/STI testing was unrelated to sexual risk behavior. Drop-in centers can play an important role in facilitating testing, including among injection drug users, but more outreach is needed to encourage testing in other at-risk subgroups.

If You Provide the Test, They will Take It: Factors Associated with HIV/STI Testing in a Representative Sample of Homeless Youth in Los Angeles*

PubMed Central

Ober, Allison J.; Martino, Steven C.; Ewing, Brett; Tucker, Joan S.

2012-01-01

Homeless youth are at high risk for human immunodeficiency virus (HIV) and other sexually transmitted infections (STI), yet those at greatest risk may never have been tested for HIV or STI. In a probability sample of sexually active homeless youth in Los Angeles (n =305), this study identifies factors associated with HIV/STI testing status. Most youth (85%) had ever been tested and 47% had tested in the past 3 months. Recent testing was significantly more likely among youth who self-identified as gay, were Hispanic, injected drugs, and used drop-in centers, and marginally more likely among youth with more depressive symptoms. Drop-in center use mediated the association of injection drug use with HIV/STI testing. HIV/STI testing was unrelated to sexual risk behavior. Drop-in centers can play an important role in facilitating testing, including among injection drug users, but more outreach is needed to encourage testing in other at-risk subgroups. PMID:22827904

System and method for implementing periodic early discard in on-chip buffer memories of network elements

DOEpatents

Francini, Andrea

2013-05-14

An advance is made over the prior art in accordance with the principles of the present invention that is directed to a new approach for a system and method for a buffer management scheme called Periodic Early Discard (PED). The invention builds on the observation that, in presence of TCP traffic, the length of a queue can be stabilized by selection of an appropriate frequency for packet dropping. For any combination of number of TCP connections and distribution of the respective RTT values, there exists an ideal packet drop frequency that prevents the queue from over-flowing or under-flowing. While the value of the ideal packet drop frequency may quickly change over time and is sensitive to the series of TCP connections affected by past packet losses, and most of all is impossible to compute inline, it is possible to approximate it with a margin of error that allows keeping the queue occupancy within a pre-defined range for extended periods of time. The PED scheme aims at tracking the (unknown) ideal packet drop frequency, adjusting the approximated value based on the evolution of the queue occupancy, with corrections of the approximated packet drop frequency that occur at a timescale that is comparable to the aggregate time constant of the set of TCP connections that traverse the queue.

Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

DOE PAGES

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

2018-04-24

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-Molecular Dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients; we use this approach to examine atomic condensation onto 6-56 atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity ( v) between atom and cluster andmore » the initial impact parameter ( b). In all cases there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms, and for 14 atom and 28 atom Mg clusters, as cluster equilibration temperature increases the condensation rate coefficient drops to values below the hard sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (> 1000 m s -1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). In conclusion, the presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.« less

Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations.

PubMed

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J

2018-04-28

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard-sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-molecular dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients. We use this approach to examine atomic condensation onto 6-56-atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity (v) between atom and cluster and the initial impact parameter (b). In all cases, there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard-sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms and for 14- and 28-atom Mg clusters, as cluster equilibration temperature increases, the condensation rate coefficient drops to values below the hard-sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (>1000 m s -1 ) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). The presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.

Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-Molecular Dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients; we use this approach to examine atomic condensation onto 6-56 atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity ( v) between atom and cluster andmore » the initial impact parameter ( b). In all cases there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms, and for 14 atom and 28 atom Mg clusters, as cluster equilibration temperature increases the condensation rate coefficient drops to values below the hard sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (> 1000 m s -1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). In conclusion, the presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.« less

Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

NASA Astrophysics Data System (ADS)

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

2018-04-01

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard-sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-molecular dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients. We use this approach to examine atomic condensation onto 6-56-atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity (v) between atom and cluster and the initial impact parameter (b). In all cases, there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard-sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms and for 14- and 28-atom Mg clusters, as cluster equilibration temperature increases, the condensation rate coefficient drops to values below the hard-sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (>1000 m s-1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). The presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.

Listening to "Frequent Flyers": What Persistently Disciplined Students Have to Say about Being Labeled as "Bad"

ERIC Educational Resources Information Center

Kennedy-Lewis, Brianna L.; Murphy, Amy S.

2016-01-01

Background: Educators' increased use of suspension and expulsion has led to some students repeatedly losing access to learning opportunities. Students excluded from school are at a higher risk of dropping out, with those who receive multiple sanctions, often called "frequent flyers" by K-12 educators, faring even worse. The loss of…

A Study of the Effects of Fieldbus Network Induced Delays on Control Systems

ERIC Educational Resources Information Center

Mainoo, Joseph

2012-01-01

Fieldbus networks are all-digital, two-way, multi-drop communication systems that are used to connect field devices such as sensors and actuators, and controllers. These fieldbus network systems are also called networked control systems (NCS). Although, there are different varieties of fieldbus networks such as Foundation Field Bus, DeviceNet, and…

The evolution of trade-offs: geographic variation in call duration and flight ability in the sand cricket, Gryllus firmus.

PubMed

Roff, D A; Crnokrak, P; Fairbairn, D J

2003-07-01

Quantitative genetic theory assumes that trade-offs are best represented by bivariate normal distributions. This theory predicts that selection will shift the trade-off function itself and not just move the mean trait values along a fixed trade-off line, as is generally assumed in optimality models. As a consequence, quantitative genetic theory predicts that the trade-off function will vary among populations in which at least one of the component traits itself varies. This prediction is tested using the trade-off between call duration and flight capability, as indexed by the mass of the dorsolateral flight muscles, in the macropterous morph of the sand cricket. We use four different populations of crickets that vary in the proportion of macropterous males (Lab = 33%, Florida = 29%, Bermuda = 72%, South Carolina = 80%). We find, as predicted, that there is significant variation in the intercept of the trade-off function but not the slope, supporting the hypothesis that trade-off functions are better represented as bivariate normal distributions rather than single lines. We also test the prediction from a quantitative genetical model of the evolution of wing dimorphism that the mean call duration of macropterous males will increase with the percentage of macropterous males in the population. This prediction is also supported. Finally, we estimate the probability of a macropterous male attracting a female, P, as a function of the relative time spent calling (P = time spent calling by macropterous male/(total time spent calling by both micropterous and macropterous male). We find that in the Lab and Florida populations the probability of a female selecting the macropterous male is equal to P, indicating that preference is due simply to relative call duration. But in the Bermuda and South Carolina populations the probability of a female selecting a macropterous male is less than P, indicating a preference for the micropterous male even after differences in call duration are accounted for.

Modeling anuran detection and site occupancy on North American Amphibian Monitoring Program (NAAMP) routes in Maryland

USGS Publications Warehouse

Weir, L.A.; Royle, J. Andrew; Nanjappa, P.; Jung, R.E.

2005-01-01

One of the most fundamental problems in monitoring animal populations is that of imperfect detection. Although imperfect detection can be modeled, studies examining patterns in occurrence often ignore detection and thus fail to properly partition variation in detection from that of occurrence. In this study, we used anuran calling survey data collected on North American Amphibian Monitoring Program routes in eastern Maryland to investigate factors that influence detection probability and site occupancy for 10 anuran species. In 2002, 17 calling survey routes in eastern Maryland were surveyed to collect environmental and species data nine or more times. To analyze these data, we developed models incorporating detection probability and site occupancy. The results suggest that, for more than half of the 10 species, detection probabilities vary most with season (i.e., day-of-year), air temperature, time, and moon illumination, whereas site occupancy may vary by the amount of palustrine forested wetland habitat. Our results suggest anuran calling surveys should document air temperature, time of night, moon illumination, observer skill, and habitat change over time, as these factors can be important to model-adjusted estimates of site occupancy. Our study represents the first formal modeling effort aimed at developing an analytic assessment framework for NAAMP calling survey data.

The formation of intestinal organoids in a hanging drop culture.

PubMed

Panek, Malgorzata; Grabacka, Maja; Pierzchalska, Malgorzata

2018-01-25

Recently organoids have become widely used in vitro models of many tissue and organs. These type of structures, originated from embryonic or adult mammalian intestines, are called "mini guts". They organize spontaneously when intestinal crypts or stem cells are embedded in the extracellular matrix proteins preparation scaffold (Matrigel). This approach has some disadvantages, as Matrigel is undefined (the concentrations of growth factors and other biologically active components in it may vary from batch to batch), difficult to handle and expensive. Here we show that the organoids derived from chicken embryo intestine are formed in a hanging drop without embedding, providing an attractive alternative for currently used protocols. Using this technique we obtained compact structures composed of contiguous organoids, which were generally similar to chicken organoids cultured in Matrigel in terms of morphology and expression of intestinal epithelial markers. Due to the simplicity, high reproducibility and throughput capacity of hanging drop technique our model may be applied in various studies concerning the gut biology.

OSLG: A new granting scheme in WDM Ethernet passive optical networks

NASA Astrophysics Data System (ADS)

Razmkhah, Ali; Rahbar, Akbar Ghaffarpour

2011-12-01

Several granting schemes have been proposed to grant transmission window and dynamic bandwidth allocation (DBA) in passive optical networks (PON). Generally, granting schemes suffer from bandwidth wastage of granted windows. Here, we propose a new granting scheme for WDM Ethernet PONs, called optical network unit (ONU) Side Limited Granting (OSLG) that conserves upstream bandwidth, thus resulting in decreasing queuing delay and packet drop ratio. In OSLG instead of optical line terminal (OLT), each ONU determines its transmission window. Two OSLG algorithms are proposed in this paper: the OSLG_GA algorithm that determines the size of its transmission window in such a way that the bandwidth wastage problem is relieved, and the OSLG_SC algorithm that saves unused bandwidth for more bandwidth utilization later on. The OSLG can be used as granting scheme of any DBA to provide better performance in the terms of packet drop ratio and queuing delay. Our performance evaluations show the effectiveness of OSLG in reducing packet drop ratio and queuing delay under different DBA techniques.

Enhanced water repellency of surfaces coated with multiscale carbon structures

NASA Astrophysics Data System (ADS)

Marchalot, Julien; Ramos, Stella. M. M.; Pirat, Christophe; Journet, Catherine

2018-01-01

Low cost and well characterized superhydrophobic surfaces are frequently required for industrial applications. Materials are commonly structured at the micro or nano scale. Surfaces decorated with nanotube derivatives synthesized by plasma enhanced chemical vapor deposition (PECVD) are of particular interest, since suitable modifications in the growth parameters can lead to numerous designs. In this article, we present surfaces that are selected for their specific wetting features with patterns ranging from dense forests to jungles with concave (re-entrant) surface such as flake-like multiscale roughness. Once these surfaces are functionalized adequately, their wetting properties are investigated. Their ability to sustain a superhydrophobic state for sessile water drops is examined. Finally, we propose a design to achieve a robust so-called ;Fakir; state, even for micrometer-sized drops, whereas with classic nanotubes forests it is not achievable. Thus, the drop remains on the apex of the protrusions with a high contact angle and a low contact angle hysteresis, while the surface features demonstrate good mechanical resistance against capillary forces.

Wireless cellular networks with Pareto-distributed call holding times

NASA Astrophysics Data System (ADS)

Rodriguez-Dagnino, Ramon M.; Takagi, Hideaki

2001-07-01

Nowadays, there is a growing interest in providing internet to mobile users. For instance, NTT DoCoMo in Japan deploys an important mobile phone network with that offers the Internet service, named 'i-mode', to more than 17 million subscribers. Internet traffic measurements show that the session duration of Call Holding Time (CHT) has probability distributions with heavy-tails, which tells us that they depart significantly from the traffic statistics of traditional voice services. In this environment, it is particularly important to know the number of handovers during a call for a network designer to make an appropriate dimensioning of virtual circuits for a wireless cell. The handover traffic has a direct impact on the Quality of Service (QoS); e.g. the service disruption due to the handover failure may significantly degrade the specified QoS of time-constrained services. In this paper, we first study the random behavior of the number of handovers during a call, where we assume that the CHT are Pareto distributed (heavy-tail distribution), and the Cell Residence Times (CRT) are exponentially distributed. Our approach is based on renewal theory arguments. We present closed-form formulae for the probability mass function (pmf) of the number of handovers during a Pareto distributed CHT, and obtain the probability of call completion as well as handover rates. Most of the formulae are expressed in terms of the Whittaker's function. We compare the Pareto case with cases of $k(subscript Erlang and hyperexponential distributions for the CHT.

Evaporation-triggered microdroplet nucleation and the four life phases of an evaporating Ouzo drop.

PubMed

Tan, Huanshu; Diddens, Christian; Lv, Pengyu; Kuerten, J G M; Zhang, Xuehua; Lohse, Detlef

2016-08-02

Evaporating liquid droplets are omnipresent in nature and technology, such as in inkjet printing, coating, deposition of materials, medical diagnostics, agriculture, the food industry, cosmetics, or spills of liquids. Whereas the evaporation of pure liquids, liquids with dispersed particles, or even liquid mixtures has intensively been studied over the past two decades, the evaporation of ternary mixtures of liquids with different volatilities and mutual solubilities has not yet been explored. Here we show that the evaporation of such ternary mixtures can trigger a phase transition and the nucleation of microdroplets of one of the components of the mixture. As a model system, we pick a sessile Ouzo droplet (as known from daily life-a transparent mixture of water, ethanol, and anise oil) and reveal and theoretically explain its four life phases: In phase I, the spherical cap-shaped droplet remains transparent while the more volatile ethanol is evaporating, preferentially at the rim of the drop because of the singularity there. This leads to a local ethanol concentration reduction and correspondingly to oil droplet nucleation there. This is the beginning of phase II, in which oil microdroplets quickly nucleate in the whole drop, leading to its milky color that typifies the so-called "Ouzo effect." Once all ethanol has evaporated, the drop, which now has a characteristic nonspherical cap shape, has become clear again, with a water drop sitting on an oil ring (phase III), finalizing the phase inversion. Finally, in phase IV, all water has evaporated, leaving behind a tiny spherical cap-shaped oil drop.

Evaporation-triggered microdroplet nucleation and the four life phases of an evaporating Ouzo drop

NASA Astrophysics Data System (ADS)

Tan, Huanshu; Diddens, Christian; Lv, Pengyu; Kuerten, J. G. M.; Zhang, Xuehua; Lohse, Detlef

2016-08-01

Evaporating liquid droplets are omnipresent in nature and technology, such as in inkjet printing, coating, deposition of materials, medical diagnostics, agriculture, the food industry, cosmetics, or spills of liquids. Whereas the evaporation of pure liquids, liquids with dispersed particles, or even liquid mixtures has intensively been studied over the past two decades, the evaporation of ternary mixtures of liquids with different volatilities and mutual solubilities has not yet been explored. Here we show that the evaporation of such ternary mixtures can trigger a phase transition and the nucleation of microdroplets of one of the components of the mixture. As a model system, we pick a sessile Ouzo droplet (as known from daily life—a transparent mixture of water, ethanol, and anise oil) and reveal and theoretically explain its four life phases: In phase I, the spherical cap-shaped droplet remains transparent while the more volatile ethanol is evaporating, preferentially at the rim of the drop because of the singularity there. This leads to a local ethanol concentration reduction and correspondingly to oil droplet nucleation there. This is the beginning of phase II, in which oil microdroplets quickly nucleate in the whole drop, leading to its milky color that typifies the so-called “Ouzo effect.” Once all ethanol has evaporated, the drop, which now has a characteristic nonspherical cap shape, has become clear again, with a water drop sitting on an oil ring (phase III), finalizing the phase inversion. Finally, in phase IV, all water has evaporated, leaving behind a tiny spherical cap-shaped oil drop.

Evaporation-triggered microdroplet nucleation and the four life phases of an evaporating Ouzo drop

PubMed Central

Tan, Huanshu; Diddens, Christian; Lv, Pengyu; Kuerten, J. G. M.; Zhang, Xuehua; Lohse, Detlef

2016-01-01

Evaporating liquid droplets are omnipresent in nature and technology, such as in inkjet printing, coating, deposition of materials, medical diagnostics, agriculture, the food industry, cosmetics, or spills of liquids. Whereas the evaporation of pure liquids, liquids with dispersed particles, or even liquid mixtures has intensively been studied over the past two decades, the evaporation of ternary mixtures of liquids with different volatilities and mutual solubilities has not yet been explored. Here we show that the evaporation of such ternary mixtures can trigger a phase transition and the nucleation of microdroplets of one of the components of the mixture. As a model system, we pick a sessile Ouzo droplet (as known from daily life—a transparent mixture of water, ethanol, and anise oil) and reveal and theoretically explain its four life phases: In phase I, the spherical cap-shaped droplet remains transparent while the more volatile ethanol is evaporating, preferentially at the rim of the drop because of the singularity there. This leads to a local ethanol concentration reduction and correspondingly to oil droplet nucleation there. This is the beginning of phase II, in which oil microdroplets quickly nucleate in the whole drop, leading to its milky color that typifies the so-called “Ouzo effect.” Once all ethanol has evaporated, the drop, which now has a characteristic nonspherical cap shape, has become clear again, with a water drop sitting on an oil ring (phase III), finalizing the phase inversion. Finally, in phase IV, all water has evaporated, leaving behind a tiny spherical cap-shaped oil drop. PMID:27418601

Forensic genetic SNP typing of low-template DNA and highly degraded DNA from crime case samples.

PubMed

Børsting, Claus; Mogensen, Helle Smidt; Morling, Niels

2013-05-01

Heterozygote imbalances leading to allele drop-outs and disproportionally large stutters leading to allele drop-ins are known stochastic phenomena related to STR typing of low-template DNA (LtDNA). The large stutters and the many drop-ins in typical STR stutter positions are artifacts from the PCR amplification of tandem repeats. These artifacts may be avoided by typing bi-allelic markers instead of STRs. In this work, the SNPforID multiplex assay was used to type LtDNA. A sensitized SNP typing protocol was introduced, that increased signal strengths without increasing noise and without affecting the heterozygote balance. Allele drop-ins were only observed in experiments with 25 pg of DNA and not in experiments with 50 and 100 pg of DNA. The allele drop-in rate in the 25 pg experiments was 0.06% or 100 times lower than what was previously reported for STR typing of LtDNA. A composite model and two different consensus models were used to interpret the SNP data. Correct profiles with 42-49 SNPs were generated from the 50 and 100 pg experiments, whereas a few incorrect genotypes were included in the generated profiles from the 25 pg experiments. With the strict consensus model, between 35 and 48 SNPs were correctly typed in the 25 pg experiments and only one allele drop-out (error rate: 0.07%) was observed in the consensus profiles. A total of 28 crime case samples were selected for typing with the sensitized SNPforID protocol. The samples were previously typed with old STR kits during the crime case investigation and only partial profiles (0-6 STRs) were obtained. Eleven of the samples could not be quantified with the Quantifiler™ Human DNA Quantification kit because of partial or complete inhibition of the PCR. For eight of these samples, SNP typing was only possible when the buffer and DNA polymerase used in the original protocol was replaced with the AmpFℓSTR(®) SEfiler Plus™ Master Mix, which was developed specifically for challenging forensic samples. All the crime case samples were successfully typed with the SNPforID multiplex assay and the match probabilities ranged from 1.1×10(-15) to 7.9×10(-23). In comparison, four of the samples could not be typed with the AmpFℓSTR(®) SEfiler Plus™ kit and the match probabilities were higher than 10(-7) for another six samples. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Performance Analysis of Power Saving Class of Type I for Voice Service in Two-Way Communication in IEEE 802.16e

NASA Astrophysics Data System (ADS)

Hwang, Eunju; Kim, Kyung Jae; Choi, Bong Dae

In IEEE 802.16e, power saving is one of the important issues for battery-powered mobile stations (MSs). We present a performance analysis of power saving class (PSC) of type I in IEEE 802.16e standard for voice over Internet protocol (VoIP) service with silence suppression in two-way communication. On-off pattern of a voice user in two-way communication is characterized by the modified Brady model, which includes short silence gaps less than 200ms and talkspurt periods shorter than 15ms, and so differs from the Brady model. Our analysis of PSC I follows the standard-based procedure for the deactivation of the sleep mode, where a uplink packet arrival during a mutual silence period wakes up the MS immediately while a downlink packet arrival waits to be served until the next listening window. We derive the delay distribution of the first downlink packet arriving during a mutual silence period, and find the dropping probability of downlink packets since a voice packet drops if it is not transmitted within maximum delay constraint. In addition, we calculate the average power consumption under the modified Brady model. Analysis and simulation results show that the sleep mode operation for the MS with VoIP service yields 32 ∼ 39% reduction in the power consumption of the MS. Finally we obtain the optimal initial/final-sleep windows that yield the minimum average power consumption while satisfying QoS constraints on the packet dropping probability and the maximum delay.

Evaluation of Two Crew Module Boilerplate Tests Using Newly Developed Calibration Metrics

NASA Technical Reports Server (NTRS)

Horta, Lucas G.; Reaves, Mercedes C.

2012-01-01

The paper discusses a application of multi-dimensional calibration metrics to evaluate pressure data from water drop tests of the Max Launch Abort System (MLAS) crew module boilerplate. Specifically, three metrics are discussed: 1) a metric to assess the probability of enveloping the measured data with the model, 2) a multi-dimensional orthogonality metric to assess model adequacy between test and analysis, and 3) a prediction error metric to conduct sensor placement to minimize pressure prediction errors. Data from similar (nearly repeated) capsule drop tests shows significant variability in the measured pressure responses. When compared to expected variability using model predictions, it is demonstrated that the measured variability cannot be explained by the model under the current uncertainty assumptions.

[On Atomic Nuclear Fusion Processes at Low-Temperatures. An Enhancement of the Probability of Transition through a Potential Barrier Due to the So-Called Barrier Anti-Zeno Effect].

PubMed

Namiot, V A

2016-01-01

It is known that in quantum mechanics the act of observing the experiment can affect the experimental findings in some cases. In particular, it happens under the so-called Zeno effect. In this work it is shown that in contrast to the "standard" Zeno-effect where the act of observing a process reduces the probability of its reality, an inverse situation when a particle transmits through a potential barrier (a so-called barrier anti-Zeno effect) can be observed, the observation of the particle essentially increases the probability of its transmission through the barrier. The possibility of using the barrier anti-Zeno effect is discussed to explain paradoxical results of experiments on "cold nuclear fusion" observed in various systems including biological ones. (According to the observers who performed the observations, the energy generation, which could not be explained by any chemical processes, as well as the change in the isotope and even element composition of the studied object may occur in these systems.

Rain Drop Charge Sensor

NASA Astrophysics Data System (ADS)

S, Sreekanth T.

begin{center} Large Large Rain Drop Charge Sensor Sreekanth T S*, Suby Symon*, G. Mohan Kumar (1) , S. Murali Das (2) *Atmospheric Sciences Division, Centre for Earth Science Studies, Thiruvananthapuram 695011 (1) D-330, Swathi Nagar, West Fort, Thiruvananthapuram 695023 (2) Kavyam, Manacaud, Thiruvananthapuram 695009 begin{center} ABSTRACT To study the inter-relations with precipitation electricity and precipitation microphysical parameters a rain drop charge sensor was designed and developed at CESS Electronics & Instrumentation Laboratory. Simultaneous measurement of electric charge and fall speed of rain drops could be done using this charge sensor. A cylindrical metal tube (sensor tube) of 30 cm length is placed inside another thick metal cover opened at top and bottom for electromagnetic shielding. Mouth of the sensor tube is exposed and bottom part is covered with metal net in the shielding cover. The instrument is designed in such a way that rain drops can pass only through unhindered inside the sensor tube. When electrically charged rain drops pass through the sensor tube, it is charged to the same magnitude of drop charge but with opposite polarity. The sensor tube is electrically connected the inverted input of a current to voltage converter operational amplifier using op-amp AD549. Since the sensor is electrically connected to the virtual ground of the op-amp, the charge flows to the ground and the generated current is converted to amplified voltage. This output voltage is recorded using a high frequency (1kHz) voltage recorder. From the recorded pulse, charge magnitude, polarity and fall speed of rain drop are calculated. From the fall speed drop diameter also can be calculated. The prototype is now under test running at CESS campus. As the magnitude of charge in rain drops is an indication of accumulated charge in clouds in lightning, this instrument has potential application in the field of risk and disaster management. By knowing the charge magnitude of initial drops from a precipitation event, gross cloud charge can be estimated and necessary precautions can be taken during convective cloud events. Being a site of high lightning incidence in tropics, Kerala state is affected in India and calls for much attention in lightning hazards mitigation. Installing this charge sensor and atmospheric electric field mill, an attempt to a better warning system can be attempted.

A Comparison of Logistic Regression, Neural Networks, and Classification Trees Predicting Success of Actuarial Students

ERIC Educational Resources Information Center

Schumacher, Phyllis; Olinsky, Alan; Quinn, John; Smith, Richard

2010-01-01

The authors extended previous research by 2 of the authors who conducted a study designed to predict the successful completion of students enrolled in an actuarial program. They used logistic regression to determine the probability of an actuarial student graduating in the major or dropping out. They compared the results of this study with those…

Likelihood of Entanglement when Materials are Dropped Vertically onto a Rotating PTO Knuckle.

PubMed

Schwab, Charles V; Rempe, Isaac J

2017-11-20

Power take-off (PTO) is a common method of transferring power from a tractor to a towed piece of machinery. The PTO is also a well-documented cause of severe and often permanent disabling injuries to farm operators. The physical conditions that cause entanglements are not well established. Several studies have explored the parameters of PTO entanglements as materials have been drawn across a rotating PTO knuckle to test for entanglement probability. The objective of this study was to determine probability of entanglement when materials are dropped vertically onto a PTO knuckle spinning at 540 rpm. A total of 360 randomized trials were conducted with ten replications for each of the six positions (center of yoke, edge of yoke rotating downward, edge of yoke rotating upward, center of cross, edge of cross rotating downward, and edge of cross rotating upward) and six different materials (woven cotton athletic shoe lace, cotton workboot lace, leather workboot lace, cotton twine, denim strip, and Tyvek strip). Not a single entanglement was recorded. Dramatic high-speed video imagery authenticated the material's motion and path as it interacted with the rotating PTO knuckle. Copyright© by the American Society of Agricultural Engineers.

Convergence of Transition Probability Matrix in CLVMarkov Models

NASA Astrophysics Data System (ADS)

Permana, D.; Pasaribu, U. S.; Indratno, S. W.; Suprayogi, S.

2018-04-01

A transition probability matrix is an arrangement of transition probability from one states to another in a Markov chain model (MCM). One of interesting study on the MCM is its behavior for a long time in the future. The behavior is derived from one property of transition probabilty matrix for n steps. This term is called the convergence of the n-step transition matrix for n move to infinity. Mathematically, the convergence of the transition probability matrix is finding the limit of the transition matrix which is powered by n where n moves to infinity. The convergence form of the transition probability matrix is very interesting as it will bring the matrix to its stationary form. This form is useful for predicting the probability of transitions between states in the future. The method usually used to find the convergence of transition probability matrix is through the process of limiting the distribution. In this paper, the convergence of the transition probability matrix is searched using a simple concept of linear algebra that is by diagonalizing the matrix.This method has a higher level of complexity because it has to perform the process of diagonalization in its matrix. But this way has the advantage of obtaining a common form of power n of the transition probability matrix. This form is useful to see transition matrix before stationary. For example cases are taken from CLV model using MCM called Model of CLV-Markov. There are several models taken by its transition probability matrix to find its convergence form. The result is that the convergence of the matrix of transition probability through diagonalization has similarity with convergence with commonly used distribution of probability limiting method.

Development and Overview of CPAS Sasquatch Airdrop Landing Location Predictor Software

NASA Technical Reports Server (NTRS)

Bledsoe, Kristin J.; Bernatovich, Michael A.

2015-01-01

The Capsule Parachute Assembly System (CPAS) is the parachute system for NASA's Orion spacecraft. CPAS is currently in the Engineering Development Unit (EDU) phase of testing. The test program consists of numerous drop tests, wherein a test article rigged with parachutes is extracted from an aircraft. During such tests, range safety is paramount, as is the recoverability of the parachutes and test article. It is crucial to establish a release point from the aircraft that will ensure that the article and all items released from it during flight will land in a designated safe area. The Sasquatch footprint tool was developed to determine this safe release point and to predict the probable landing locations (footprints) of the payload and all released objects. In 2012, a new version of Sasquatch, called Sasquatch Polygons, was developed that significantly upgraded the capabilities of the footprint tool. Key improvements were an increase in the accuracy of the predictions, and the addition of an interface with the Debris Tool (DT), an in-flight debris avoidance tool for use on the test observation helicopter. Additional enhancements include improved data presentation for communication with test personnel and a streamlined code structure. This paper discusses the development, validation, and performance of Sasquatch Polygons, as well as its differences from the original Sasquatch footprint tool.

Study on bi-directional pedestrian movement using ant algorithms

NASA Astrophysics Data System (ADS)

Sibel, Gokce; Ozhan, Kayacan

2016-01-01

A cellular automata model is proposed to simulate bi-directional pedestrian flow. Pedestrian movement is investigated by using ant algorithms. Ants communicate with each other by dropping a chemical, called a pheromone, on the substrate while crawling forward. Similarly, it is considered that oppositely moving pedestrians drop ‘visual pheromones’ on their way and the visual pheromones might cause attractive or repulsive interactions. This pheromenon is introduced into modelling the pedestrians’ walking preference. In this way, the decision-making process of pedestrians will be based on ‘the instinct of following’. At some densities, the relationships of velocity-density and flux-density are analyzed for different evaporation rates of visual pheromones. Lane formation and phase transition are observed for certain evaporation rates of visual pheromones.

Notice Concerning Making Good Preparations for the Beginning of the New School Year, 1988.

PubMed

1988-01-01

Among other things, this Notice directs localities to take measures to stop the tendency of students to drop out of primary and secondary schools; to carry out propaganda on the Chinese Compulsory Education Law before school begins; and to organize personnel to re-educate students who have dropped out of school or who, even though of school age, have not attended school, as well as their parents, urging them to resume or start school education. The Notice also calls on education departments to cooperate with departments in charge of labor, agriculture, rural enterprise management, and industrial and commercial administration in inhibiting the illegal practice of hiring children under the age of 16. full text

Teaching Uncertainties

ERIC Educational Resources Information Center

Duerdoth, Ian

2009-01-01

The subject of uncertainties (sometimes called errors) is traditionally taught (to first-year science undergraduates) towards the end of a course on statistics that defines probability as the limit of many trials, and discusses probability distribution functions and the Gaussian distribution. We show how to introduce students to the concepts of…

Directed Design of Experiments (DOE) for Determining Probability of Detection (POD) Capability of NDE Systems (DOEPOD)

NASA Technical Reports Server (NTRS)

Generazio, Ed

2007-01-01

This viewgraph presentation reviews some of the issues that people who specialize in Non destructive evaluation (NDE) have with determining the statistics of the probability of detection. There is discussion of the use of the binominal distribution, and the probability of hit. The presentation then reviews the concepts of Directed Design of Experiments for Validating Probability of Detection of Inspection Systems (DOEPOD). Several cases are reviewed, and discussed. The concept of false calls is also reviewed.

Buckling vs. particle desorption in a particle-covered drop subject to compressive surface stresses: a simulation study.

PubMed

Gu, Chuan; Botto, Lorenzo

2018-01-31

Predicting the behaviour of particle-covered fluid interfaces under compression has implications in several fields. The surface-tension driven adhesion of particles to drops and bubbles is exploited for example to enhance the stability of foams and emulsion and develop new generation materials. When a particle-covered fluid interface is compressed, one can observe either smooth buckling or particle desorption from the interface. The microscopic mechanisms leading to the buckling-to-desorption transition are not fully understood. In this paper we simulate a spherical drop covered by a monolayer of spherical particles. The particle-covered interface is subject to time-dependent compressive surface stresses that mimic the slow deflation of the drop. The buckling-to-desorption transition depends in a non-trivial way on three non-dimensional parameters: the ratio Π s /γ of particle-induced surface pressure and bare surface tension, the ratio a/R of particle and drop radii, and the parameter f characterising the strength of adhesion of each particle to the interface. Based on the insights from the simulations, we propose a configuration diagram describing the effect of these controlling parameters. We find that particle desorption is highly correlated with a mechanical instability that produces small-scale undulations of the monolayer of the order of the particle size that grow when the surface pressure is sufficiently large. We argue that the large local curvature associated with these small undulations can produce large normal forces, enhancing the probability of desorption.

Program calculates Z-factor for natural gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coker, A.K.

The Fortran program called Physic presented in this article calculates the gas deviation or compressibility factor, Z, of natural gas. The author has used the program for determining discharge-piping pressure drop. The calculated Z is within 5% accuracy for natural hydrocarbon gas with a specific gravity between 0.5 and 0.8, and at a pressure below 5,000 psia.

State Policies to Reengage Dropouts. Issue Brief

ERIC Educational Resources Information Center

NGA Center for Best Practices, 2011

2011-01-01

Efforts to improve educational attainment are hampered by the high school dropout crisis. At a time when governors are calling for changes to improve higher education access and success, more than 1 million youth ages 16 to 19 are not enrolled in school and do not have a high school diploma. Each year, an additional 390,000 youth drop out of…

75 FR 30052 - Nomans Land Island National Wildlife Refuge, Town of Chilmark, MA

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-28

... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R5-R-2009-N185; BAC-4311-K9-S3] Nomans Land Island National Wildlife Refuge, Town of Chilmark, MA AGENCY: Fish and Wildlife Service, Interior... Weir Hill Road, Sudbury, MA 01776. In-Person Drop-off, Viewing, or Pickup: Call 978-443-4661 to make an...

Is There Anything You Do in Music Class that Students Take with Them when They Leave?

ERIC Educational Resources Information Center

Teaching Music, 2007

2007-01-01

In this installment of "Members Speak Out," the author discusses a game that teachers can play with their band and orchestra students. Called "Drop the Needle," it involves starting a musical recording in the middle and trying to determine what period it is from and who might have composed it. This game allows more experienced…

Notes from the (Battle)field for Equity in Education

ERIC Educational Resources Information Center

Murtadha, Khaula

2009-01-01

There is a growing public awareness of the national drop-out crisis, but it does not, in the author's view, tell the whole story. It does not call attention to the fact that the most glaring need for new teachers and principals is in high-poverty areas where teaching conditions are the most challenging and where official public support has often…

Need 3 Quick Credits to Play Ball? Call Western Oklahoma

ERIC Educational Resources Information Center

Wolverton, Brad

2012-01-01

Western Oklahoma State College's name comes up whenever athletes get themselves in a jam: They've failed a class. They've dropped another. Maybe they're just short on credits. But they still want to play. Western Oklahoma gives them a chance, offering three credits in two weeks--and for less than $400. Almost as appealing: The community college…

The effect of various parameters of large scale radio propagation models on improving performance mobile communications

NASA Astrophysics Data System (ADS)

Pinem, M.; Fauzi, R.

2018-02-01

One technique for ensuring continuity of wireless communication services and keeping a smooth transition on mobile communication networks is the soft handover technique. In the Soft Handover (SHO) technique the inclusion and reduction of Base Station from the set of active sets is determined by initiation triggers. One of the initiation triggers is based on the strong reception signal. In this paper we observed the influence of parameters of large-scale radio propagation models to improve the performance of mobile communications. The observation parameters for characterizing the performance of the specified mobile system are Drop Call, Radio Link Degradation Rate and Average Size of Active Set (AS). The simulated results show that the increase in altitude of Base Station (BS) Antenna and Mobile Station (MS) Antenna contributes to the improvement of signal power reception level so as to improve Radio Link quality and increase the average size of Active Set and reduce the average Drop Call rate. It was also found that Hata’s propagation model contributed significantly to improvements in system performance parameters compared to Okumura’s propagation model and Lee’s propagation model.

A fuzzy call admission control scheme in wireless networks

NASA Astrophysics Data System (ADS)

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

2007-11-01

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.

Monte Carlo simulation of the risk of contamination of apples with Escherichia coli O157:H7.

PubMed

Duffy, Siobain; Schaffner, Donald W

2002-10-25

Quantitative descriptions of the frequency and extent of contamination of apple cider with pathogenic bacteria were obtained using literature data and computer simulation. Probability distributions were chosen to describe the risk of apple contamination by each suspected pathway. Tree-picked apples may be contaminated by birds infected with Escherichia coli O157:H7 when orchards were located near a sewage source (ocean or landfill). Dropped apples could become contaminated from either infected animal droppings or from contaminated manure if used as fertilizer. A risk assessment model was created in Analytica. The results of worst-case simulations revealed that 6-9 log CFU E. coli O157:H7 might be found on a harvest of 1000 dropped apples, while 3-4 log CFU contamination could be present on 1000 tree-picked apples. This model confirms that practices such as using dropped apples and using animal waste as fertilizer increase risk in the production of apple cider, and that pasteurization may not eliminate all contamination in juice from heavily contaminated fruit. Recently published FDA regulations for juices requiring a 5-log CFU/ml reduction of pathogenic bacteria in fresh juices should be a fail-safe measure for apples harvested in all but the worst-case scenarios.

A drop in performance on a fluid intelligence test due to instructed-rule mindset.

PubMed

ErEl, Hadas; Meiran, Nachshon

2017-09-01

A 'mindset' is a configuration of processing resources that are made available for the task at hand as well as their suitable tuning for carrying it out. Of special interest, remote-relation abstract mindsets are introduced by activities sharing only general control processes with the task. To test the effect of a remote-relation mindset on performance on a Fluid Intelligence test (Raven's Advanced Progressive Matrices, RAPM), we induced a mindset associated with little usage of executive processing by requiring participants to execute a well-defined classification rule 12 times, a manipulation known from previous work to drastically impair rule-generation performance and associated cognitive processes. In Experiment 1, this manipulation led to a drop in RAPM performance equivalent to 10.1 IQ points. No drop was observed in a General Knowledge task. In Experiment 2, a similar drop in RAPM performance was observed (equivalent to 7.9 and 9.2 IQ points) regardless if participants were pre-informed about the upcoming RAPM test. These results indicate strong (most likely, transient) adverse effects of a remote-relation mindset on test performance. They imply that although the trait of Fluid Intelligence has probably not changed, mindsets can severely distort estimates of this trait.

Maximum predictive power and the superposition principle

NASA Technical Reports Server (NTRS)

Summhammer, Johann

1994-01-01

In quantum physics the direct observables are probabilities of events. We ask how observed probabilities must be combined to achieve what we call maximum predictive power. According to this concept the accuracy of a prediction must only depend on the number of runs whose data serve as input for the prediction. We transform each probability to an associated variable whose uncertainty interval depends only on the amount of data and strictly decreases with it. We find that for a probability which is a function of two other probabilities maximum predictive power is achieved when linearly summing their associated variables and transforming back to a probability. This recovers the quantum mechanical superposition principle.

Investigating investigators: examining witnesses' influence on investigators.

PubMed

Dahl, Leora C; Lindsay, D Stephen; Brimacombe, C A Elizabeth

2006-12-01

This research examined the influence of eyewitness identification decisions on participants in the role of police investigators. Undergraduate "investigators" interviewed confederate "witnesses" and then searched a computer database of potential suspects. The database included information on each suspect's physical description, prior criminal record, alibi, and fingerprints. Participants selected a suspect and estimated the probability that the suspect was guilty. Investigators subsequently administered a photo lineup to the witness and re-estimated the suspect's guilt. If the witness identified the suspect probability estimates increased dramatically. If the witness identified an innocent lineup member or rejected the lineup, investigators' probability estimates dropped significantly, even when pre-lineup objective evidence (e.g., fingerprints) was strong. Performance of participants acting as witnesses in two baseline studies was at chance. Therefore, participant-investigators greatly overestimated the amount of information gain provided by eyewitness identifications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frangakis, Constantine; Geschwind, Jean-Francois; Kim, Daniel

Introduction: The drop-off risk for patients awaiting liver transplantation for hepatocellular carcinoma (HCC) is 22%. Transplant liver availability is expected to worsen, resulting in longer waiting times and increased drop-off rates. Our aim was to determine whether chemoembolization can decrease this risk. Patients and Methods: Eighty-seven consecutive HCC patients listed for liver transplant (Milan criteria) underwent statistical comparability adjustments using the propensity score (Wilcoxon, Fisher's, and chi-square tests). Forty-three nonchemoembolization patients and 22 chemoembolization patients were comparable for Child-Pugh and Model for End-Stage Liver Disease scores, tumor size and number, alpha fetoprotein (AFP) levels, and cause of cirrhosis. We calculatedmore » the risk of dropping off the transplant list by assigning a transplant time to those who dropped off (equal probability with patients who were on the list longer than the patient in question). The significance level was obtained by calculating the simulation distribution of the difference compared with the permutations of chemoembolization versus nonchemoembolization assignment of the patients. Kaplan-Meier estimators (log-rank test) were used to determine survival rates. Results: Median follow-up was 187 {+-} 110 weeks (range 38 to 435, date of diagnosis). The chemoembolization group had an 80% drop-off risk decrease (15% nonchemoembolization versus 3% chemoembolization, p = 0.04). Although survival was better for the chemoembolization group, it did not reach statistical significance. Two-year survival for the nonchemoembolization and chemoembolization group was 57.3% {+-} 7.1% and 76.0% {+-} 7.9%, respectively (p = 0.078). Conclusions: Chemoembolization appears to result in a significant decrease in the risk of dropping off liver transplant list for patients with HCC and results in a tendency toward longer survival.« less

The preparation of Drosophila embryos for live-imaging using the hanging drop protocol.

PubMed

Reed, Bruce H; McMillan, Stephanie C; Chaudhary, Roopali

2009-03-13

Green fluorescent protein (GFP)-based timelapse live-imaging is a powerful technique for studying the genetic regulation of dynamic processes such as tissue morphogenesis, cell-cell adhesion, or cell death. Drosophila embryos expressing GFP are readily imaged using either stereoscopic or confocal microscopy. A goal of any live-imaging protocol is to minimize detrimental effects such as dehydration and hypoxia. Previous protocols for preparing Drosophila embryos for live-imaging analysis have involved placing dechorionated embryos in halocarbon oil and sandwiching them between a halocarbon gas-permeable membrane and a coverslip. The introduction of compression through mounting embryos in this manner represents an undesirable complication for any biomechanical-based analysis of morphogenesis. Our method, which we call the hanging drop protocol, results in excellent viability of embryos during live imaging and does not require that embryos be compressed. Briefly, the hanging drop protocol involves the placement of embryos in a drop of halocarbon oil that is suspended from a coverslip, which is, in turn, fixed in position over a humid chamber. In addition to providing gas exchange and preventing dehydration, this arrangement takes advantage of the buoyancy of embryos in halocarbon oil to prevent them from drifting out of position during timelapse acquisition. This video describes in detail how to collect and prepare Drosophila embryos for live imaging using the hanging drop protocol. This protocol is suitable for imaging dechorionated embryos using stereomicroscopy or any upright compound fluorescence microscope.

Experimental and numerical study of drill bit drop tests on Kuru granite.

PubMed

Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko

2017-01-28

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy.This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'. © 2016 The Author(s).

Experimental and numerical study of drill bit drop tests on Kuru granite

PubMed Central

Kane, Alexandre; Hokka, Mikko

2017-01-01

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit–rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist–Johnson–Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue ‘Experimental testing and modelling of brittle materials at high strain rates’. PMID:27956511

Faraday forcing of high-temperature levitated liquid metal drops for the measurement of surface tension.

PubMed

Brosius, Nevin; Ward, Kevin; Matsumoto, Satoshi; SanSoucie, Michael; Narayanan, Ranga

2018-01-01

In this work, a method for the measurement of surface tension using continuous periodic forcing is presented. To reduce gravitational effects, samples are electrostatically levitated prior to forcing. The method, called Faraday forcing, is particularly well suited for fluids that require high temperature measurements such as liquid metals where conventional surface tension measurement methods are not possible. It offers distinct advantages over the conventional pulse-decay analysis method when the sample viscosity is high or the levitation feedback control system is noisy. In the current method, levitated drops are continuously translated about a mean position at a small, constant forcing amplitude over a range of frequencies. At a particular frequency in this range, the drop suddenly enters a state of resonance, which is confirmed by large executions of prolate/oblate deformations about the mean spherical shape. The arrival at this resonant condition is a signature that the parametric forcing frequency is equal to the drop's natural frequency, the latter being a known function of surface tension. A description of the experimental procedure is presented. A proof of concept is given using pure Zr and a Ti 39.5 Zr 39.5 Ni 21 alloy as examples. The results compare favorably with accepted literature values obtained using the pulse-decay method.

Do breeding phase and detection distance influence the effective area surveyed for northern goshawks?

USGS Publications Warehouse

Roberson, A.M.; Andersen, D.E.; Kennedy, P.L.

2005-01-01

Broadcast surveys using conspecific calls are currently the most effective method for detecting northern goshawks (Accipiter gentilis) during the breeding season. These surveys typically use alarm calls during the nestling phase and juvenile food-begging calls during the fledgling-dependency phase. Because goshawks are most vocal during the courtship phase, we hypothesized that this phase would be an effective time to detect goshawks. Our objective was to improve current survey methodology by evaluating the probability of detecting goshawks at active nests in northern Minnesota in 3 breeding phases and at 4 broadcast distances and to determine the effective area surveyed per broadcast station. Unlike previous studies, we broadcast calls at only 1 distance per trial. This approach better quantifies (1) the relationship between distance and probability of detection, and (2) the effective area surveyed (EAS) per broadcast station. We conducted 99 broadcast trials at 14 active breeding areas. When pooled over all distances, detection rates were highest during the courtship (70%) and fledgling-dependency phases (68%). Detection rates were lowest during the nestling phase (28%), when there appeared to be higher variation in likelihood of detecting individuals. EAS per broadcast station was 39.8 ha during courtship and 24.8 ha during fledgling-dependency. Consequently, in northern Minnesota, broadcast stations may be spaced 712m and 562 m apart when conducting systematic surveys during courtship and fledgling-dependency, respectively. We could not calculate EAS for the nestling phase because probability of detection was not a simple function of distance from nest. Calculation of EAS could be applied to other areas where the probability of detection is a known function of distance.

Splash evaluation of SRB designs

NASA Technical Reports Server (NTRS)

Counter, D. N.

1974-01-01

A technique is developed to optimize the shuttle solid rocket booster (SRB) design for water impact loads. The SRB is dropped by parachute and recovered at sea for reuse. Loads experienced at water impact are design critical. The probability of each water impact load is determined using a Monte Carlo technique and an aerodynamic analysis of the SRB parachute system. Meteorological effects are included and four configurations are evaluated.

Were Minority Students Discouraged from Applying to University of California Campuses after the Affirmative Action Ban?

ERIC Educational Resources Information Center

Antonovics, Kate; Backes, Ben

2013-01-01

This paper uses student-level data to investigate how the college application behavior of underrepresented minorities (URMs) changed in response to the 1998 end of affirmative action in admissions at the University of California (UC). We show that all URMs experienced a drop in their probability of admission to at least one UC campus. However, the…

Probability-Based Ship Design Procedures: A Demonstration. Phase 1.

DTIC Science & Technology

1992-09-01

Although actuarially speaking, this should refer to the probability that the structure catastrophically fails, the term is generally and widely used as a...termed "empty", while otherwise they are called "qualified" upcrossings, a terminology devised by Vanmarcke ( ASME , J. Applied Mechanics, March 1975

Large Deviations: Advanced Probability for Undergrads

ERIC Educational Resources Information Center

Rolls, David A.

2007-01-01

In the branch of probability called "large deviations," rates of convergence (e.g. of the sample mean) are considered. The theory makes use of the moment generating function. So, particularly for sums of independent and identically distributed random variables, the theory can be made accessible to senior undergraduates after a first course in…

A Spectrum Access Based on Quality of Service (QoS) in Cognitive Radio Networks.

PubMed

Zhai, Linbo; Wang, Hua; Gao, Chuangen

2016-01-01

The quality of service (QoS) is important issue for cognitive radio networks. In the cognitive radio system, the licensed users, also called primary users (PUs), are authorized to utilize the wireless spectrum, while unlicensed users, also called secondary users (SUs), are not authorized to use the wireless spectrum. SUs access the wireless spectrum opportunistically when the spectrum is idle. While SUs use an idle channel, the instance that PUs come back makes SUs terminate their communications and leave the current channel. Therefore, quality of service (QoS) is difficult to be ensured for SUs. In this paper, we first propose an analysis model to obtain QoS for cognitive radio networks such as blocking probability, completed traffic and termination probability of SUs. When the primary users use the channels frequently, QoS of SUs is difficult to be ensured, especially the termination probability. Then, we propose a channel reservation scheme to improve QoS of SUs. The scheme makes the terminated SUs move to the reserved channels and keep on communications. Simulation results show that our scheme can improve QoS of SUs especially the termination probability with a little cost of blocking probability in dynamic environment.

Modeling Achievement Trajectories when Attrition Is Informative

ERIC Educational Resources Information Center

Feldman, Betsy J.; Rabe-Hesketh, Sophia

2012-01-01

In longitudinal education studies, assuming that dropout and missing data occur completely at random is often unrealistic. When the probability of dropout depends on covariates and observed responses (called "missing at random" [MAR]), or on values of responses that are missing (called "informative" or "not missing at random" [NMAR]),…

Relationship of starch changes to puffing expansion of parboiled rice.

PubMed

Mahanta, Charu Lata; Bhattacharya, K R

2010-03-01

'Intan' variety of paddy (Oryza sativa) was tested for puffing. It was parboiled under a wide range of paddy moisture content, steaming pressure and time, as also temperature and time of sand heating. The resulting milled rices were studied for their diverse properties including puffing. Indices of starch changes in the samples were calculated as: (1) gelatinisation index from the solubility of amylose in 0.2 N KOH; (2) amylopectin retrogradation from the post-production drop in room-temperature hydration power of the parboiled paddy during air-drying, (3) thermal breakdown of starch from the drop in gel permeation chromatographic fraction I of starch; lipid-amylose complexation indirectly from (4) drop in rate of water uptake during cooking and (5) cooked-rice firmness. It was found that the puffing expansion was very highly correlated with the combined above 5 indices of starch changes, as much as 90% of the variation in puffing being explainable on that basis. Puffing was promoted by gelatinisation as well as lipid-amylose complexation, but was retarded by amylopectin retrogradation and probably starch breakdown.

Electrodiagnosis of ulnar neuropathy at the elbow (Une): a Bayesian approach.

PubMed

Logigian, Eric L; Villanueva, Raissa; Twydell, Paul T; Myers, Bennett; Downs, Marlene; Preston, David C; Kothari, Milind J; Herrmann, David N

2014-03-01

In ulnar neuropathy at the elbow (UNE), we determined how electrodiagnostic cutoffs [across-elbow ulnar motor conduction velocity slowing (AECV-slowing), drop in across-elbow vs. forearm CV (AECV-drop)] depend on pretest probability (PreTP). Fifty clinically defined UNE patients and 50 controls underwent ulnar conduction testing recording abductor digiti minimi (ADM) and first dorsal interosseous (FDI), stimulating wrist, below-elbow, and 6-, 8-, and 10-cm more proximally. For various PreTPs of UNE, the cutoffs required to confirm UNE (defined as posttest probability = 95%) were determined with receiver operator characteristic (ROC) curves and Bayes Theorem. On ROC and Bayesian analyses, the ADM 10-cm montage was optimal. For PreTP = 0.25, the confirmatory cutoffs were >23 m/s (AECV-drop), and <38 m/s (AECV-slowing); for PreTP = 0.75, they were much less conservative: >14 m/s, and <47 m/s, respectively. (1) In UNE, electrodiagnostic cutoffs are critically dependent on PreTP; rigid cutoffs are problematic. (2) AE distances should be standardized and at least 10 cm. Copyright © 2013 Wiley Periodicals, Inc.

You Know English, so Why Don't You Teach?" Language Ideologies and Returnees Becoming English Language Teachers in Mexico

ERIC Educational Resources Information Center

Christiansen, M. Sidury; Trejo Guzmán, Nelly Paulina; Mora-Pablo, Irasema

2018-01-01

Return migration from the United States to Mexico has been increasing in the last decade. Research reports that many returnees, who are English dominant, drop out of school to look for work in call centers and transnational companies (Anderson, 2015). Others pursue higher education in English-based programs such as those for becoming English…

A Road to Understanding: A Qualitative Study into Why Learners Drop out of a Blended Language Learning (BLL) Environment

ERIC Educational Resources Information Center

Stracke, Elke

2007-01-01

This paper addresses the views of students of blended language learning (BLL)--a particular learning and teaching environment, that combines face-to-face (f2f) and computer-assisted language learning (CALL). In this instance, the "blend" consisted of learners' independent self-study phases at a computer, with a CD-ROM, and traditional f2f…

Creating Jaw-Droppingly Effective Rookie Teachers: Unpacking Teacher Preparation at the Sposato Graduate School of Education (Match Education)

ERIC Educational Resources Information Center

Miller, Andrew Frederic

2017-01-01

Beginning in 2000, a number of new graduate schools of education (nGSEs) have been established in the U.S. in response to increasing calls for more effective teachers. Among these are programs affiliated with "No Excuses"-style charter schools, which are focused on closing the achievement gap in urban K-12 schools. Teacher education…

Susceptibility of central hardwood trees to stem breakage due to ice glazing

Treesearch

KaDonna C. Randolph

2014-01-01

During January 26-28, 2009, a winter storm dropped a mix of rain, ice, and snow from Texas across the Ohio River Valley and into New England. The storm caused multiple fatalities and millions of dollars of property damage and was called "the biggest natural disaster in modern Kentucky history" (Brammer and Funk 2009: 13). The storm disturbed an estimated 2.4...

Of parachuting spiders and meat-eating beetles

USGS Publications Warehouse

Booth, W.

1990-01-01

Here and there on the rolling hills of gray volcanic ash around the volcano are clumps of invading fireweed and another pioneer called pearly everlasting. Alder and Willow saplings grow sporadically along the otherwise barren stream courses. Plugs of grass sprout in piles of elk droppings. And deer mic and pocket gophers, the survivialists of the animal world, also have managed to gain foothold. 

Prediction of Postoperative Clinical Recovery of Drop Foot Attributable to Lumbar Degenerative Diseases, via a Bayesian Network.

PubMed

Takenaka, Shota; Aono, Hiroyuki

2017-03-01

Drop foot resulting from degenerative lumbar diseases can impair activities of daily living. Therefore, predictors of recovery of this symptom have been investigated using univariate or/and multivariate analyses. However, the conclusions have been somewhat controversial. Bayesian network models, which are graphic and intuitive to the clinician, may facilitate understanding of the prognosis of drop foot resulting from degenerative lumbar diseases. (1) To show a layered correlation among predictors of recovery from drop foot resulting from degenerative lumbar diseases; and (2) to develop support tools for clinical decisions to treat drop foot resulting from lumbar degenerative diseases. Between 1993 and 2013, we treated 141 patients with decompressive lumbar spine surgery who presented with drop foot attributable to degenerative diseases. Of those, 102 (72%) were included in this retrospective study because they had drop foot of recent development and had no diseases develop that affect evaluation of drop foot after surgery. Specifically, 28 (20%) patients could not be analyzed because their records were not available at a minimum of 2 years followup after surgery and 11 (8%) were lost owing to postoperative conditions that affect the muscle strength evaluation. Eight candidate variables were sex, age, herniated soft disc, duration of the neurologic injury (duration), preoperative tibialis anterior muscle strength (pretibialis anterior), leg pain, cauda equina syndrome, and number of involved levels. Manual muscle testing was used to assess the tibialis anterior muscle strength. Drop foot was defined as a tibialis anterior muscle strength score of less than 3 of 5 (5 = movement against gravity and full resistance, 4 = movement against gravity and moderate resistance, 3 = movement against gravity through full ROM, 3- = movement against gravity through partial ROM, 2 = movement with gravity eliminated through full ROM, 1 = slight contraction but no movement, and 0 = no contraction). The two outcomes of interest were postoperative tibialis anterior muscle strength (posttibialis anterior) of 3 or greater and posttibialis anterior strength of 4 or greater at 2 years after surgery. We developed two separate Bayesian network models with outcomes of interest for posttibialis anterior strength of 3 or greater and posttibialis anterior strength of 4 or greater. The two outcomes correspond to "good" and "excellent" results based on previous reports, respectively. Direct predictors are defined as variables that have the tail of the arrow connecting the outcome of interest, whereas indirect predictors are defined as variables that have the tail of the arrow connecting either direct predictors or other indirect predictors that have the tail of the arrow connecting direct predictors. Sevenfold cross validation and receiver-operating characteristic (ROC) curve analyses were performed to evaluate the accuracy and robustness of the Bayesian network models. Both of our Bayesian network models showed that weaker muscle power before surgery (pretibialis anterior ≤ 1) and longer duration of neurologic injury before treatment (> 30 days) were associated with a decreased likelihood of return of function by 2 years. The models for posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater were the same in terms of the graphs, showing that the two direct predictors were pretibialis anterior muscle strength (score ≤ 1 or ≥ 2) and duration (≤ 30 days or > 30 days). Age, herniated soft disc, and leg pain were identified as indirect predictors. We developed a decision-support tool in which the clinician can enter pretibialis anterior muscle strength and duration, and from this obtain the probability estimates of posttibialis anterior muscle strength. The probability estimates of posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater were 94% and 85%, respectively, in the most-favorable conditions (pretibialis anterior ≥ 2; duration ≤ 30 days) and 18% and 14%, respectively, in the least-favorable conditions (pretibialis anterior ≤ 1; duration > 30 days). On the sevenfold cross validation, the area under the ROC curve yielded means of 0.78 (95% CI, 0.68-0.87) and 0.74 (95% CI, 0.64-0.84) for posttibialis anterior muscle strength of 3 or greater and posttibialis anterior muscle strength of 4 or greater, respectively. The results of this study suggest that the clinician can understand intuitively the layered correlation among predictors by Bayesian network models. Based on the models, the decision-support tool successfully provided the probability estimates of posttibialis anterior muscle strength to treat drop foot attributable to lumbar degenerative diseases. These models were shown to be robust on the internal validation but should be externally validated in other populations. Level III, therapeutic study.

Soot agglomeration in isolated, free droplet combustion

NASA Technical Reports Server (NTRS)

Choi, M. Y.; Dryer, F. L.; Green, G. J.; Sangiovanni, J. J.

1993-01-01

Under the conditions of an isolated, free droplet experiment, hollow, carbonaceous structures, called soot spheres, were observed to form during the atmospheric pressure, low Reynolds number combustion of 1-methylnaphthalene. These structures which are agglomerates composed of smaller spheroidal units result from both thermophoretic effects induced by the envelope flame surrounding each drop and aerodynamic effects caused by changes in the relative gas/drop velocities. A chemically reacting flow model was used to analyze the process of sootshell formation during microgravity droplet combustion. The time-dependent temperature and gas property field surrounding the droplet was determined, and the soot cloud location for microgravity combustion of n-heptane droplets was predicted. Experiments showed that the sooting propensity of n-alkane fuel droplets can be varied through diluent substitution, oxygen-index variations, and ambient pressure reductions.

Single-cell barcoding and sequencing using droplet microfluidics.

PubMed

Zilionis, Rapolas; Nainys, Juozas; Veres, Adrian; Savova, Virginia; Zemmour, David; Klein, Allon M; Mazutis, Linas

2017-01-01

Single-cell RNA sequencing has recently emerged as a powerful tool for mapping cellular heterogeneity in diseased and healthy tissues, yet high-throughput methods are needed for capturing the unbiased diversity of cells. Droplet microfluidics is among the most promising candidates for capturing and processing thousands of individual cells for whole-transcriptome or genomic analysis in a massively parallel manner with minimal reagent use. We recently established a method called inDrops, which has the capability to index >15,000 cells in an hour. A suspension of cells is first encapsulated into nanoliter droplets with hydrogel beads (HBs) bearing barcoding DNA primers. Cells are then lysed and mRNA is barcoded (indexed) by a reverse transcription (RT) reaction. Here we provide details for (i) establishing an inDrops platform (1 d); (ii) performing hydrogel bead synthesis (4 d); (iii) encapsulating and barcoding cells (1 d); and (iv) RNA-seq library preparation (2 d). inDrops is a robust and scalable platform, and it is unique in its ability to capture and profile >75% of cells in even very small samples, on a scale of thousands or tens of thousands of cells.

Swimming behaviour of the upside-down swimming catfish ( Synodontis nigriventris) at high-quality microgravity - A drop-tower experiment

NASA Astrophysics Data System (ADS)

Anken, R.; Hilbig, R.

2009-07-01

The catfish Synodontis nigriventris often shows a unique swimming behaviour in being oriented upside-down. When swimming near a (e.g., vertical) substrate, however, the animals orient themselves with their ventral side towards this substrate. This tendency is called ventral substrate response (VSR). The VSR does not only override the upside-down swimming behaviour but also the dorsal light response and the ventral light response. In the course of an earlier drop-tower experiment performed at ZARM (Bremen, Germany) using cichlid fish ( Oreochromis mossambicus), we had observed that about 90% of the animals revealed sensorimotor disorders (kinetotic swimming) due to the almost complete lack of gravity as a cue for orientation. In order to further assess the importance of the VSR for postural control in S. nigriventris when being located near a substrate, we subjected catfish in relatively small chambers to drop-tower flights. In contrast to our results regarding cichlid fish, S. nigriventris showed no kinetotic behaviour. This clearly suggests that the VSR overrides even vestibular input and possibly represents the most important single behavioural response in this species.

Liquid rims collisions and the formation of fines

NASA Astrophysics Data System (ADS)

Néel, Baptiste; Villermaux, Emmanuel

2017-11-01

As an elementary mechanism for the formation of drops from liquid sheets, we investigate the collision of liquid cylinders. This results from the opening of two nearby holes on a liquid film, growing at a constant speed while collecting liquid into two rims, eventually colliding with each other. In this surface tension driven phenomenon, a unique Weber number We = ρ(2 V) 2 2 a / σ controls a variety of behaviors (ρ , σ are the liquid density and surface tension, and 2 V the relative velocity of the impinging rims, each of individual radius a). At low We , the rims merge through an inelastic, dissipative collision which produces a corrugated ligament, finally breaking into drops of size scaling like a, on average. Above a critical Wec 60 , the collision leads to a splash, with the formation of a thin transverse liquid sheet. We will describe the expansion-retraction dynamics of this secondary sheet and its destabilization, responsible for the production of a mist of finer droplets. These alter sensibly the mean, and overall drops size distribution, thus weighted by a substantial fraction of so-called fines.

Drop coalescence and liquid flow in a single Plateau border

NASA Astrophysics Data System (ADS)

Cohen, Alexandre; Fraysse, Nathalie; Raufaste, Christophe

2015-05-01

We report a comprehensive study of the flow of liquid triggered by injecting a droplet into a liquid foam microchannel, also called a Plateau border. This drop-injected experiment reveals an intricate dynamics for the liquid redistribution, with two contrasting regimes observed, ruled either by inertia or viscosity. We devoted a previous study [A. Cohen et al., Phys. Rev. Lett. 112, 218303 (2014), 10.1103/PhysRevLett.112.218303] to the inertial imbibition regime, unexpected at such small length scales. Here we report other features of interest of the drop-injected experiment, related to the coalescence of the droplet with the liquid microchannel, to both the inertial and viscous regimes, and to the occurrence of liquid flow through the soap films as well as effects of the interfacial rheology. The transition between the two regimes is investigated and qualitatively accounted for. The relevance of our results to liquid foam drainage is tackled by considering the flow of liquid at the nodes of the network of interconnected microchannels. Extensions of our study to liquid foams are discussed.

The influence of aluminium, steel and polyurethane shoeing systems and of the unshod hoof on the injury risk of a horse kick. An ex vivo experimental study.

PubMed

Sprick, Miriam; Fürst, Anton; Baschnagel, Fabio; Michel, Silvain; Piskoty, Gabor; Hartnack, Sonja; Jackson, Michelle A

2017-09-12

To evaluate the damage inflicted by an unshod hoof and by the various horseshoe materials (steel, aluminium and polyurethane) on the long bones of horses after a simulated kick. Sixty-four equine radii and tibiae were evaluated using a drop impact test setup. An impactor with a steel, aluminium, polyurethane, or hoof horn head was dropped onto prepared bones. An impactor velocity of 8 m/s was initially used with all four materials and then testing was repeated with a velocity of 12 m/s with the polyurethane and hoof horn heads. The impact process was analysed using a high-speed camera, and physical parameters, including peak contact force and impact duration, were calculated. At 8 m/s, the probability of a fracture was 75% for steel and 81% for aluminium, whereas polyurethane and hoof horn did not damage the bones. At 12 m/s, the probability of a fracture was 25% for polyurethane and 12.5% for hoof horn. The peak contact force and impact duration differed significantly between 'hard materials' (aluminium and steel) and 'soft materials' (polyurethane and hoof horn). The observed bone injuries were similar to those seen in analogous experimental studies carried out previously and comparable to clinical fracture cases suggesting that the simulated kick was realistic. The probability of fracture was significantly higher for steel and aluminium than for polyurethane and hoof horn, which suggests that the horseshoe material has a significant influence on the risk of injury for humans or horses kicked by a horse.

Quality improvement and cost reduction realized by a purchaser through diabetes disease management.

PubMed

Snyder, James W; Malaskovitz, Joyce; Griego, Janet; Persson, Jeffrey; Flatt, Kristy

2003-01-01

This report documents the clinical improvements and costs experienced by a purchaser after introduction of a diabetes disease management program. A purchaser contracted with American Healthways, a disease management organization, to initiate a diabetes disease management program called Diabetes Decisions. Started in 1998, the program grew to include 662 participants. The results reported are based on the continuously participating population (12 months of participation in the program for the reporting year). Participants were entered into American Healthways' clinical information system and risk-stratified, and an individualized treatment plan was devised. Outbound telephone calls by specially trained nurses were a key intervention. Data were collected on key process measures, financial parameters, and participant satisfaction. By year 3, there were 422 continuously participating participants. From baseline to the third year of the program, significant increases in frequency of A1C testing (21.3% to 82.2%), dilated retinal exams (17.2% to 70.7%), and performance of foot exams (2.0% to 75.6%) were noted. For 166 participants with five A1C determinations, A1C values dropped from 8.89% to 7.88%. Participants experienced a 36% drop in inpatient costs. Without adjustment for medical inflation, total medical costs decreased by 26.8% from the baseline period, dropping to $268.63 per diabetes participant per month (PDPPM) by year 3, a gross savings of $98.49 PDPPM. After subtracting the fees paid to Diabetes Decisions, a net savings of $986,538 was realized. This yielded a return on investment of 3.37. By investing in a diabetes disease management program, a purchaser was able to realize significant improvements in clinical care, substantial cost savings, and a favorable return on investment.

Fluctuation relation for heat exchange in Markovian open quantum systems

NASA Astrophysics Data System (ADS)

Ramezani, M.; Golshani, M.; Rezakhani, A. T.

2018-04-01

A fluctuation relation for the heat exchange of an open quantum system under a thermalizing Markovian dynamics is derived. We show that the probability that the system absorbs an amount of heat from its bath, at a given time interval, divided by the probability of the reverse process (releasing the same amount of heat to the bath) is given by an exponential factor which depends on the amount of heat and the difference between the temperatures of the system and the bath. Interestingly, this relation is akin to the standard form of the fluctuation relation (for forward-backward dynamics). We also argue that the probability of the violation of the second law of thermodynamics in the form of the Clausius statement (i.e., net heat transfer from a cold system to its hot bath) drops exponentially with both the amount of heat and the temperature differences of the baths.

Fluctuation relation for heat exchange in Markovian open quantum systems.

PubMed

Ramezani, M; Golshani, M; Rezakhani, A T

2018-04-01

A fluctuation relation for the heat exchange of an open quantum system under a thermalizing Markovian dynamics is derived. We show that the probability that the system absorbs an amount of heat from its bath, at a given time interval, divided by the probability of the reverse process (releasing the same amount of heat to the bath) is given by an exponential factor which depends on the amount of heat and the difference between the temperatures of the system and the bath. Interestingly, this relation is akin to the standard form of the fluctuation relation (for forward-backward dynamics). We also argue that the probability of the violation of the second law of thermodynamics in the form of the Clausius statement (i.e., net heat transfer from a cold system to its hot bath) drops exponentially with both the amount of heat and the temperature differences of the baths.

Turbulent aerosol fluxes over the Arctic Ocean: 2. Wind-driven sources from the sea

NASA Astrophysics Data System (ADS)

Nilsson, E. D.; Rannik, Ü.; Swietlicki, E.; Leck, C.; Aalto, P. P.; Zhou, J.; Norman, M.

2001-12-01

An eddy-covariance flux system was successfully applied over open sea, leads and ice floes during the Arctic Ocean Expedition in July-August 1996. Wind-driven upward aerosol number fluxes were observed over open sea and leads in the pack ice. These particles must originate from droplets ejected into the air at the bursting of small air bubbles at the water surface. The source flux F (in 106 m-2 s-1) had a strong dependency on wind speed, log>(F>)=0.20U¯-1.71 and 0.11U¯-1.93, over the open sea and leads, respectively (where U¯ is the local wind speed at about 10 m height). Over the open sea the wind-driven aerosol source flux consisted of a film drop mode centered at ˜100 nm diameter and a jet drop mode centered at ˜1 μm diameter. Over the leads in the pack ice, a jet drop mode at ˜2 μm diameter dominated. The jet drop mode consisted of sea-salt, but oxalate indicated an organic contribution, and bacterias and other biogenic particles were identified by single particle analysis. Particles with diameters less than -100 nm appear to have contributed to the flux, but their chemical composition is unknown. Whitecaps were probably the bubble source at open sea and on the leads at high wind speed, but a different bubble source is needed in the leads owing to their small fetch. Melting of ice in the leads is probably the best candidate. The flux over the open sea was of such a magnitude that it could give a significant contribution to the condensation nuclei (CCN) population. Although the flux from the leads were roughly an order of magnitude smaller and the leads cover only a small fraction of the pack ice, the local source may till be important for the CCN population in Arctic fogs. The primary marine aerosol source will increase both with increased wind speed and with decreased ice fraction and extent. The local CCN production may therefore increase and influence cloud or fog albedo and lifetime in response to greenhouse warming in the Arctic Ocean region.

Re-Conceptualization of Modified Angoff Standard Setting: Unified Statistical, Measurement, Cognitive, and Social Psychological Theories

ERIC Educational Resources Information Center

Iyioke, Ifeoma Chika

2013-01-01

This dissertation describes a design for training, in accordance with probability judgment heuristics principles, for the Angoff standard setting method. The new training with instruction, practice, and feedback tailored to the probability judgment heuristics principles was called the Heuristic training and the prevailing Angoff method training…

Assessing bat detectability and occupancy with multiple automated echolocation detectors

Treesearch

Marcos P. Gorresen; Adam C. Miles; Christopher M. Todd; Frank J. Bonaccorso; Theodore J. Weller

2008-01-01

Occupancy analysis and its ability to account for differential detection probabilities is important for studies in which detecting echolocation calls is used as a measure of bat occurrence and activity. We examined the feasibility of remotely acquiring bat encounter histories to estimate detection probability and occupancy. We used echolocation detectors coupled o...

Employee responses to health insurance premium increases.

PubMed

Goldman, Dana P; Leibowitz, Arleen A; Robalino, David A

2004-01-01

To determine the sensitivity of employees' health insurance decisions--including the decision to not choose health maintenance organization or fee-for-service coverage--during periods of rapidly escalating healthcare costs. A retrospective cohort study of employee plan choices at a single large firm with a "cafeteria-style" benefits plan wherein employees paid all the additional cost of purchasing more generous insurance. We modeled the probability that an employee would drop coverage or switch plans in response to employee premium increases using data from a single large US company with employees across 47 states during the 3-year period of 1989 through 1991, a time of large premium increases within and across plans. Premium increases induced substantial plan switching. Single employees were more likely to respond to premium increases by dropping coverage, whereas families tended to switch to another plan. Premium increases of 10% induced 7% of single employees to drop or severely cut back on coverage; 13% to switch to another plan; and 80% to remain in their existing plan. Similar figures for those with family coverage were 11%, 12%, and 77%, respectively. Simulation results that control for known covariates show similar increases. When faced with a dramatic increase in premiums--on the order of 20%--nearly one fifth of the single employees dropped coverage compared with 10% of those with family coverage. Employee coverage decisions are sensitive to rapidly increasing premiums, and single employees may be likely to drop coverage. This finding suggests that sustained premium increases could induce substantial increases in the number of uninsured individuals.

Occultation detection of a Neptunian ring-like arc

NASA Technical Reports Server (NTRS)

Hubbard, W. B.; Brahic, A.; Sicardy, B.; Roques, F.; Elicer, L.-R.; Vilas, F.

1986-01-01

The apparent closest approach of the star SAO186001 to Neptune was observed photoelectrically on July 22, 1984 at Cerro Tololo Inter-American Observatory. A 32-percent signal drop, lasting about 1.2 s, was probably caused by a partially transparent arc of material at a distance of 67,000 km from Neptune. Neptune's arc(s) do not vary smoothly with azimuth, unlike the rings of other Jovian planets.

Role of gravity in the formation of bacterial colonies with a hydrophobic surface layer

NASA Astrophysics Data System (ADS)

Puzyr, A. P.; Tirranen, L. K.; Krylova, T. Y.; Borodina, E. V.

A simple technique for determining hydrophobic-hydrophilic properties of bacterial colonies surface, which involves putting a drop of liquid with known properties (e.g. water, oil) on their surface, has been described. This technique allows quick estimate of wettability of bacterial colony surface, i.e. its hydrophobic-hydrophilic properties. The behaviour of water drops on colonies of bacteria Bacillus five strains (of different types) has been studied. It was revealed that 1) orientation in the Earth gravity field during bacterial growth can define the form of colonies with hydrophobic surface; 2) the form and size of the colony are dependent on the extention ability, most probably, of the hydrophobic layer; 3) the Earth gravity field (gravity) serves as a 'pump' providing and keeping water within the colony. We suppose that at growing colonies on agar media the inflow of water-soluble nutrient materials takes place both due to diffusion processes and directed water current produced by the gravity. The revealed effect probably should be taken into consideration while constructing the models of colonies growing on dense nutrient media. The easily determined hydrophobic properties of colonies surface can become a systematic feature after collecting more extensive data on the surface hydrophobic-hydrophilic properties of microorganism colonies of other types and species.

Exploratory analysis of real personal emergency response call conversations: considerations for personal emergency response spoken dialogue systems.

PubMed

Young, Victoria; Rochon, Elizabeth; Mihailidis, Alex

2016-11-14

The purpose of this study was to derive data from real, recorded, personal emergency response call conversations to help improve the artificial intelligence and decision making capability of a spoken dialogue system in a smart personal emergency response system. The main study objectives were to: develop a model of personal emergency response; determine categories for the model's features; identify and calculate measures from call conversations (verbal ability, conversational structure, timing); and examine conversational patterns and relationships between measures and model features applicable for improving the system's ability to automatically identify call model categories and predict a target response. This study was exploratory and used mixed methods. Personal emergency response calls were pre-classified according to call model categories identified qualitatively from response call transcripts. The relationships between six verbal ability measures, three conversational structure measures, two timing measures and three independent factors: caller type, risk level, and speaker type, were examined statistically. Emergency medical response services were the preferred response for the majority of medium and high risk calls for both caller types. Older adult callers mainly requested non-emergency medical service responders during medium risk situations. By measuring the number of spoken words-per-minute and turn-length-in-words for the first spoken utterance of a call, older adult and care provider callers could be identified with moderate accuracy. Average call taker response time was calculated using the number-of-speaker-turns and time-in-seconds measures. Care providers and older adults used different conversational strategies when responding to call takers. The words 'ambulance' and 'paramedic' may hold different latent connotations for different callers. The data derived from the real personal emergency response recordings may help a spoken dialogue system classify incoming calls by caller type with moderate probability shortly after the initial caller utterance. Knowing the caller type, the target response for the call may be predicted with some degree of probability and the output dialogue could be tailored to this caller type. The average call taker response time measured from real calls may be used to limit the conversation length in a spoken dialogue system before defaulting to a live call taker.

Amphibian Bioacoustics

NASA Astrophysics Data System (ADS)

Christensen-Dalsgaard, Jakob

Anuran amphibians (frogs and toads) of most of the 3,500 species that exist today are highly vocal animals. In most frogs, males will spend considerable energy on calling and incur sizeable predation risks and the females’ detection and localization of the calls of conspecific males is often a prerequisite for successful mating. Therefore, acoustic communication is evidently evolutionarily important in the anurans, and their auditory system is probably shaped by the selective pressures associated with production, detection and localization of the communication calls.

Stress drop inferred from dynamic rupture simulations consistent with Moment-Rupture area empirical scaling models: Effects of week shallow zone

NASA Astrophysics Data System (ADS)

Dalguer, L. A.; Miyake, H.; Irikura, K.; Wu, H., Sr.

2016-12-01

Empirical scaling models of seismic moment and rupture area provide constraints to parameterize source parameters, such as stress drop, for numerical simulations of ground motion. There are several scaling models published in the literature. The effect of the finite width seismogenic zone and the free-surface have been attributed to cause the breaking of the well know self-similar scaling (e.g. Dalguer et al, 2008) given origin to the so called L and W models for large faults. These models imply the existence of three-stage scaling relationship between seismic moment and rupture area (e.g. Irikura and Miyake, 2011). In this paper we extend the work done by Dalguer et al 2008, in which these authors calibrated fault models that match the observations showing that the average stress drop is independent of earthquake size for buried earthquakes, but scale dependent for surface-rupturing earthquakes. Here we have developed additional sets of dynamic rupture models for vertical strike slip faults to evaluate the effect of the weak shallow layer (WSL) zone for the calibration of stress drop. Rupture in the WSL zone is expected to operate with enhanced energy absorption mechanism. The set of dynamic models consists of fault models with width 20km and fault length L=20km, 40km, 60km, 80km, 100km, 120km, 200km, 300km and 400km and average stress drop values of 2.0MPa, 2.5MPa, 3.0MPa, 3.5MPa, 5.0MPa and 7.5MPa. For models that break the free-surface, the WSL zone is modeled assuming a 2km width with stress drop 0.0MPa or -2.0 MPa. Our results show that depending on the characterization of the WSL zone, the average stress drop at the seismogenic zone that fit the empirical models changes. If WSL zone is not considered, that is, stress drop at SL zone is the same as the seismogenic zone, average stress drop is about 20% smaller than models with WSL zone. By introducing more energy absorption at the SL zone, that could be the case of large mature faults, the average stress drop in the seismogenic zone increases. Suggesting that large earthquakes need higher stress drop to break the fault than buried and moderate earthquakes. Therefore, the value of the average stress drop for large events that break the free-source depend on the definition of the WSL. Suggesting that the WSL plays an important role on the prediction of final slip and fault displacement.

Temporal changes of static stress drop as a proxy for poroelastic effects at The Geysers geothermal field, California

NASA Astrophysics Data System (ADS)

Staszek, Monika; Orlecka-Sikora, Beata; Lasocki, Stanislaw; Kwiatek, Grzegorz; Leptokaropoulos, Konstantinos; Martinez-Garzon, Patricia

2017-04-01

One of the major environmental impacts of shale gas exploitation is triggered and induced seismicity. Due to the similarity of fluid injection process data from geothermal fields can be used as a proxy for shale gas exploitation associated seismicity. Therefore, in this paper we utilize 'The Geysers' dataset compiled within SHale gas Exploration and Exploitation induced Risks (SHEER) project. The dependence of earthquake static stress drops on pore pressure in the medium was previously suggested by Goertz-Allmann et al. (2011), who observed an increase of the static stress drop with the distance from injection well during reservoir stimulation at Deep Heat Mining project in Basel, Switzerland. Similar observation has been done by Kwiatek et al. (2014) in Berlín geothermal field, El Salvador. In this study, we use a high-quality data from The Geysers geothermal field to determine whether the static stress drops and the stress drop distributions change statistically significantly in time or not, and how such changes are correlated with the values of hypocenter depth, water injection rate, and distance from injection well. For the analyses we use a group of 354 earthquakes, which occurred in the proximity of Prati-9 and Prati-29 injection wells. Spectral parameters of these earthquakes were determined using mesh spectral ratio technique. Our results indicate that: (1) the static stress drop variation in time is statistically significant, (2) median static stress drop is inversely related to median injection rate. Therefore, it is highly expected that static stress drop is influenced by pore pressure in underground fluid injection conditions. References: Goertz-Allmann B., Goertz A., Wiemer S. (2011), Stress drop variations of induced earthquakes at the Basel geothermal site. Geophysical Research Letters, 38, L09308, doi:10.1029/2011GL047498. Kwiatek G., Bulut F., Bohnhoff M., Dresen G. (2014), High-resolution analysis of seismicity induced at Berlin geothermal field, El Salvador. Geothermics, 52, 98-111, doi: 10.1016/j.geothermics.2013.09.008. Acknowledgements: This work was supported under SHEER: "Shale Gas Exploration and Exploitation Induced Risks" project funded from Horizon 2020 - R&I Framework Programme, call H2020-LCE-2014-1 and by the Ministry of Science and Higher Education of Poland under project no. 500-10-27.

Association of multiple ischemic strokes with mortality in incident hemodialysis patients: an application of multistate model to determine transition probabilities in a retrospective observational cohort.

PubMed

Wetmore, James B; Mahnken, Jonathan D; Phadnis, Milind A

2016-09-21

Little is known about the effect of multiple, or subsequent, ischemic strokes in patients receiving hemodialysis. We undertook a retrospective cohort study of incident hemodialysis patients with Medicare coverage who had experienced a first ischemic stroke. Factors associated with either a subsequent ischemic stroke or death following a first new stroke were modeled. A multistate model with Cox proportional hazards was used to predict transition probabilities from first ischemic stroke to either subsequent stroke or to death, and the demographic and clinical factors associated with the respective transition probabilities were determined. Effect of a subsequent ischemic stroke on survival was quantified. Overall, 12,054 individuals (mean age 69.7 years, 41.3 % male, 53.0 % Caucasian and 34.0 % African-American) experienced a first new ischemic stroke. Female sex was associated with an increased risk of having a subsequent ischemic stroke (adjusted hazard ratio 1.37, 95 % confidence intervals 1.20 - 1.56, P < 0.0001); African-Americans, as compared to Caucasians, had lower likelihood of dying after a first new ischemic stroke (0.81, 0.77 - 0.85, P < 0.0001). A subsequent stroke trended towards having a higher likelihood of transitioning to death compared to a first new ischemic stroke on dialysis (1.72, 0.96 - 3.09, P = 0.071). When a subsequent ischemic stroke occurs at 24 months, probability of survival dropped >15 %, in absolute terms, from 0.254 to 0.096, with substantial drops observed at subsequent time points such that the probability of survival was more than halved. Likelihood of subsequent ischemic stroke and of survival in hemodialysis patients appears to vary by sex and race: females are more likely than males to experience a subsequent ischemic stroke, and Caucasians are more likely than African-Americans to die after a first new ischemic stroke. The risk of a transitioning to a subsequent stroke (after having had a first) increases until about 1 year, then decreases. Subsequent strokes are associated with decreased probability of survival, an effect which increases as time since first stroke elapses. This information may be of assistance to clinicians when counseling hemodialysis patients about the implications of recurrent ischemic stroke.

Sacra Fossae

NASA Image and Video Library

2018-04-19

Located on the western margin of Lunae Planum, Sacra Fossae is a group of linear depressions. The right angle turns and uniform width seen in this VIS image indicate that these channels were formed by faulting rather than liquid flow. Two bounding faults with a down-dropped interior are called graben. Orbit Number: 71244 Latitude: 17.7623 Longitude: 288.309 Instrument: VIS Captured: 2018-01-05 09:06 https://photojournal.jpl.nasa.gov/catalog/PIA22373

The Politics of Language and National School Reform: The Gaelic League's Call for an Irish Ireland, 1893-1922

ERIC Educational Resources Information Center

Laukaitis, John

2010-01-01

With the colonization of Ireland in the 17th century by Cromwellian and Williamite forces, the spread of English as a language of power marked a linguistic shift as Anglicization and economic necessity transformed Irish to a vernacular of the poor. Where Irish was spoken by almost all throughout the country in the 17th century, a steady drop began…

Advanced regenerator testing in the Raytheon dual-use cryocoolerr

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schaefer, B. R.; Bellis, L.; Ellis, M. J.

2014-01-29

Significant progress has been made on the Raytheon low cost space cryocooler called the Dual-Use Cryocooler (DUC). Most notably, the DUC has been integrated and tested with an advanced regenerator. The advanced regenerator is a drop-in replacement for stainless steel screens and has shown significant thermodynamic performance improvements. This paper will compare the performance of two different regenerators and explain the benefits of the advanced regenerator.

Newtonian Analysis of a Folded Chain Drop

ERIC Educational Resources Information Center

Mungan, Carl E.

2018-01-01

Consider a chain of length L that hangs in a U shape with end A fixed to a rigid support and free end E released from rest starting from the same initial height (call it y = 0) as A. Figure 1 sketches the chain after end E has fallen a distance y. Points O and A are assumed to be close enough to each other and the chain flexible enough that the…

A neutron spectrometer based on temperature variations in superheated drop compositions

NASA Astrophysics Data System (ADS)

Apfel, Robert E.; d'Errico, Francesco

2002-01-01

The response of superheated drop detectors (SDDs) to neutron radiation varies in a self-consistent manner with variations in temperature and pressure, making such compositions suitable for neutron spectrometry. The advantage of this approach is that the response functions of candidate materials versus energy as the temperature or pressure is varied are nested and have distinct thresholds, with no thermal neutron response. These characteristics permit unfolding without the uncertainties associated with other spectrometry techniques, where multiple solutions are possible, thus requiring an initial guess of the spectrum. A spectrometer was developed based on the well-established technology for acoustic sensing of bubble events interfaced with a proportional-integral-derivative temperature controller. The active monitor for neutrons, called REMbrandt™, was used as the platform for controlling temperature on a SDD probe and for data acquisition, thereby automating the process of measuring the neutron energy spectrum. The new instrument, called REM-SPEC™, implements and automates the original BINS approach: it adjusts the temperature of the SDD vial in increasing steps and measures the bubble event rate at each step. By using two distinct SDD materials with overlapping responses, the 0.1-20 MeV range of energies relevant to practical spectrometry is readily covered. Initial experiments with an Am-Be source validate the operational protocols of this device.

Design and analysis of a model predictive controller for active queue management.

PubMed

Wang, Ping; Chen, Hong; Yang, Xiaoping; Ma, Yan

2012-01-01

Model predictive (MP) control as a novel active queue management (AQM) algorithm in dynamic computer networks is proposed. According to the predicted future queue length in the data buffer, early packets at the router are dropped reasonably by the MPAQM controller so that the queue length reaches the desired value with minimal tracking error. The drop probability is obtained by optimizing the network performance. Further, randomized algorithms are applied to analyze the robustness of MPAQM successfully, and also to provide the stability domain of systems with uncertain network parameters. The performances of MPAQM are evaluated through a series of simulations in NS2. The simulation results show that the MPAQM algorithm outperforms RED, PI, and REM algorithms in terms of stability, disturbance rejection, and robustness. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

National surveillance for radiological exposures and intentional potassium iodide and iodine product ingestions in the United States associated with the 2011 Japan radiological incident

PubMed Central

LAW, ROYAL K.; SCHIER, JOSH G.; MARTIN, COLLEEN A.; OLIVARES, DAGNY E.; THOMAS, RICHARD G.; BRONSTEIN, ALVIN C.; CHANG, ARTHUR S.

2015-01-01

Background In March of 2011, an earthquake struck Japan causing a tsunami that resulted in a radiological release from the damaged Fukushima Daiichi nuclear power plant. Surveillance for potential radiological and any iodine/iodide product exposures was initiated on the National Poison Data System (NPDS) to target public health messaging needs within the United States (US). Our objectives are to describe self-reported exposures to radiation, potassium iodide (KI) and other iodine/iodide products which occurred during the US federal response and discuss its public health impact. Methods All calls to poison centers associated with the Japan incident were identified from March 11, 2011 to April 18, 2011 in NPDS. Exposure, demographic and health outcome information were collected. Calls about reported radiation exposures and KI or other iodine/iodide product ingestions were then categorized with regard to exposure likelihood based on follow-up information obtained from the PC where each call originated. Reported exposures were subsequently classified as probable exposures (high likelihood of exposure), probable non-exposures (low likelihood of exposure), and suspect exposure (unknown likelihood of exposure). Results We identified 400 calls to PCs associated with the incident, with 340 information requests (no exposure reported) and 60 reported exposures. The majority (n = 194; 57%) of the information requests mentioned one or more substances. Radiation was inquired about most frequently (n = 88; 45%), followed by KI (n = 86; 44%) and other iodine/iodide products (n = 47; 24%). Of the 60 reported exposures, KI was reported most frequently (n = 25; 42%), followed by radiation (n = 22; 37%) and other iodine/iodide products (n = 13; 22%). Among reported KI exposures, most were classified as probable exposures (n = 24; 96%); one was a probable non-exposure. Among reported other iodine/iodide product exposures, most were probable exposures (n = 10, 77%) and the rest were suspect exposures (n = 3; 23%). The reported radiation exposures were classified as suspect exposures (n = 16, 73%) or probable non-exposures (n = 6; 27%). No radiation exposures were classified as probable exposures. A small number of the probable exposures to KI and other iodide/iodine products reported adverse signs or symptoms (n = 9; 26%). The majority of probable exposures had no adverse outcomes (n = 28; 82%). These data identified a potential public health information gap regarding KI and other iodine/iodide products which was then addressed through public health messaging activities. Conclusion During the Japan incident response, surveillance activities using NPDS identified KI and other iodine/iodide products as potential public health concerns within the US, which guided CDC’s public health messaging and communication activities. Regional PCs can provide timely and additional information during a public health emergency to enhance data collected from surveillance activities, which in turn can be used to inform public health decision-making. PMID:23043524

National surveillance for radiological exposures and intentional potassium iodide and iodine product ingestions in the United States associated with the 2011 Japan radiological incident.

PubMed

Law, Royal K; Schier, Josh G; Martin, Colleen A; Olivares, Dagny E; Thomas, Richard G; Bronstein, Alvin C; Chang, Arthur S

2013-01-01

In March of 2011, an earthquake struck Japan causing a tsunami that resulted in a radiological release from the damaged Fukushima Daiichi nuclear power plant. Surveillance for potential radiological and any iodine/iodide product exposures was initiated on the National Poison Data System (NPDS) to target public health messaging needs within the United States (US). Our objectives are to describe self-reported exposures to radiation, potassium iodide (KI) and other iodine/iodide products which occurred during the US federal response and discuss its public health impact. All calls to poison centers associated with the Japan incident were identified from March 11, 2011 to April 18, 2011 in NPDS. Exposure, demographic and health outcome information were collected. Calls about reported radiation exposures and KI or other iodine/iodide product ingestions were then categorized with regard to exposure likelihood based on follow-up information obtained from the PC where each call originated. Reported exposures were subsequently classified as probable exposures (high likelihood of exposure), probable non-exposures (low likelihood of exposure), and suspect exposure (unknown likelihood of exposure). We identified 400 calls to PCs associated with the incident, with 340 information requests (no exposure reported) and 60 reported exposures. The majority (n = 194; 57%) of the information requests mentioned one or more substances. Radiation was inquired about most frequently (n = 88; 45%), followed by KI (n = 86; 44%) and other iodine/iodide products (n = 47; 24%). Of the 60 reported exposures, KI was reported most frequently (n = 25; 42%), followed by radiation (n = 22; 37%) and other iodine/iodide products (n = 13; 22%). Among reported KI exposures, most were classified as probable exposures (n = 24; 96%); one was a probable non-exposure. Among reported other iodine/iodide product exposures, most were probable exposures (n = 10, 77%) and the rest were suspect exposures (n = 3; 23%). The reported radiation exposures were classified as suspect exposures (n = 16, 73%) or probable non-exposures (n = 6; 27%). No radiation exposures were classified as probable exposures. A small number of the probable exposures to KI and other iodide/iodine products reported adverse signs or symptoms (n = 9; 26%). The majority of probable exposures had no adverse outcomes (n = 28; 82%). These data identified a potential public health information gap regarding KI and other iodine/iodide products which was then addressed through public health messaging activities. During the Japan incident response, surveillance activities using NPDS identified KI and other iodine/iodide products as potential public health concerns within the US, which guided CDC's public health messaging and communication activities. Regional PCs can provide timely and additional information during a public health emergency to enhance data collected from surveillance activities, which in turn can be used to inform public health decision-making.

Promoting Active Learning When Teaching Introductory Statistics and Probability Using a Portfolio Curriculum Approach

ERIC Educational Resources Information Center

Adair, Desmond; Jaeger, Martin; Price, Owen M.

2018-01-01

The use of a portfolio curriculum approach, when teaching a university introductory statistics and probability course to engineering students, is developed and evaluated. The portfolio curriculum approach, so called, as the students need to keep extensive records both as hard copies and digitally of reading materials, interactions with faculty,…

Intelligent call admission control for multi-class services in mobile cellular networks

NASA Astrophysics Data System (ADS)

Ma, Yufeng; Hu, Xiulin; Zhang, Yunyu

2005-11-01

Scarcity of the spectrum resource and mobility of users make quality of service (QoS) provision a critical issue in mobile cellular 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 of each service class. Simulation compares the proposed fuzzy scheme with complete sharing and guard channel policies. Simulation results show that fuzzy scheme has a better robust performance in terms of average blocking criterion.

Numerical Simulation of Hydrodynamics of a Heavy Liquid Drop Covered by Vapor Film in a Water Pool

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, W.M.; Yang, Z.L.; Giri, A.

2002-07-01

A numerical study on the hydrodynamics of a droplet covered by vapor film in water pool is carried out. Two level set functions are used as to implicitly capture the interfaces among three immiscible fluids (melt-drop, vapor and coolant). This approach leaves only one set of conservation equations for the three phases. A high-order Navier-Stokes solver, called Cubic-Interpolated Pseudo-Particle (CIP) algorithm, is employed in combination with level set approach, which allows large density ratios (up to 1000), surface tension and jump in viscosity. By this calculation, the hydrodynamic behavior of a melt droplet falling into a volatile coolant is simulated,more » which is of great significance to reveal the mechanism of steam explosion during a hypothetical severe reactor accident. (authors)« less

The 2011 M = 9.0 Tohoku oki earthquake more than doubled the probability of large shocks beneath Tokyo

USGS Publications Warehouse

Toda, Shinji; Stein, Ross S.

2013-01-01

1] The Kanto seismic corridor surrounding Tokyo has hosted four to five M ≥ 7 earthquakes in the past 400 years. Immediately after the Tohoku earthquake, the seismicity rate in the corridor jumped 10-fold, while the rate of normal focal mechanisms dropped in half. The seismicity rate decayed for 6–12 months, after which it steadied at three times the pre-Tohoku rate. The seismicity rate jump and decay to a new rate, as well as the focal mechanism change, can be explained by the static stress imparted by the Tohoku rupture and postseismic creep to Kanto faults. We therefore fit the seismicity observations to a rate/state Coulomb model, which we use to forecast the time-dependent probability of large earthquakes in the Kanto seismic corridor. We estimate a 17% probability of a M ≥ 7.0 shock over the 5 year prospective period 11 March 2013 to 10 March 2018, two-and-a-half times the probability had the Tohoku earthquake not struck

Analysis of the effects of periodic forcing in the spike rate and spike correlation's in semiconductor lasers with optical feedback

NASA Astrophysics Data System (ADS)

Quintero-Quiroz, C.; Sorrentino, Taciano; Torrent, M. C.; Masoller, Cristina

2016-04-01

We study the dynamics of semiconductor lasers with optical feedback and direct current modulation, operating in the regime of low frequency fluctuations (LFFs). In the LFF regime the laser intensity displays abrupt spikes: the intensity drops to zero and then gradually recovers. We focus on the inter-spike-intervals (ISIs) and use a method of symbolic time-series analysis, which is based on computing the probabilities of symbolic patterns. We show that the variation of the probabilities of the symbols with the modulation frequency and with the intrinsic spike rate of the laser allows to identify different regimes of noisy locking. Simulations of the Lang-Kobayashi model are in good qualitative agreement with experimental observations.

Break-up dynamics of fluctuating liquid threads

PubMed Central

Petit, Julien; Rivière, David; Kellay, Hamid; Delville, Jean-Pierre

2012-01-01

The thinning dynamics of a liquid neck before break-up, as may happen when a drop detaches from a faucet or a capillary, follows different rules and dynamic scaling laws depending on the importance of inertia, viscous stresses, or capillary forces. If now the thinning neck reaches dimensions comparable to the thermally excited interfacial fluctuations, as for nanojet break-up or the fragmentation of thermally annealed nanowires, these fluctuations should play a dominant role according to recent theory and observations. Using near-critical interfaces, we here fully characterize the universal dynamics of this thermal fluctuation-dominated regime and demonstrate that the cross-over from the classical two-fluid pinch-off scenario of a liquid thread to the fluctuation-dominated regime occurs at a well-defined neck radius proportional to the thermal length scale. Investigating satellite drop formation, we also show that at the level of the cross-over between these two regimes it is more probable to produce monodisperse droplets because fluctuation-dominated pinch-off may allow the unique situation where satellite drop formation can be inhibited. Nonetheless, the interplay between the evolution of the neck profiles from the classical to the fluctuation-dominated regime and the satellites’ production remains to be clarified. PMID:23090994

Plan curvature and landslide probability in regions dominated by earth flows and earth slides

USGS Publications Warehouse

Ohlmacher, G.C.

2007-01-01

Damaging landslides in the Appalachian Plateau and scattered regions within the Midcontinent of North America highlight the need for landslide-hazard mapping and a better understanding of the geomorphic development of landslide terrains. The Plateau and Midcontinent have the necessary ingredients for landslides including sufficient relief, steep slope gradients, Pennsylvanian and Permian cyclothems that weather into fine-grained soils containing considerable clay, and adequate precipitation. One commonly used parameter in landslide-hazard analysis that is in need of further investigation is plan curvature. Plan curvature is the curvature of the hillside in a horizontal plane or the curvature of the contours on a topographic map. Hillsides can be subdivided into regions of concave outward plan curvature called hollows, convex outward plan curvature called noses, and straight contours called planar regions. Statistical analysis of plan-curvature and landslide datasets indicate that hillsides with planar plan curvature have the highest probability for landslides in regions dominated by earth flows and earth slides in clayey soils (CH and CL). The probability of landslides decreases as the hillsides become more concave or convex. Hollows have a slightly higher probability for landslides than noses. In hollows landslide material converges into the narrow region at the base of the slope. The convergence combined with the cohesive nature of fine-grained soils creates a buttressing effect that slows soil movement and increases the stability of the hillside within the hollow. Statistical approaches that attempt to determine landslide hazard need to account for the complex relationship between plan curvature, type of landslide, and landslide susceptibility. ?? 2007 Elsevier B.V. All rights reserved.

Gravity Bias in Young and Adult Chimpanzees ("Pan Troglodytes"): Tests with a Modified Opaque-Tubes Task

ERIC Educational Resources Information Center

Tomonaga, Masaki; Imura, Tomoko; Mizuno, Yuu; Tanaka, Masayuki

2007-01-01

Young human children at around 2 years of age fail to predict the correct location of an object when it is dropped from the top of an S-shape opaque tube. They search in the location just below the releasing point (Hood, 1995). This type of error, called a "gravity bias", has recently been reported in dogs and monkeys. In the present study, we…

Quantum probability assignment limited by relativistic causality.

PubMed

Han, Yeong Deok; Choi, Taeseung

2016-03-14

Quantum theory has nonlocal correlations, which bothered Einstein, but found to satisfy relativistic causality. Correlation for a shared quantum state manifests itself, in the standard quantum framework, by joint probability distributions that can be obtained by applying state reduction and probability assignment that is called Born rule. Quantum correlations, which show nonlocality when the shared state has an entanglement, can be changed if we apply different probability assignment rule. As a result, the amount of nonlocality in quantum correlation will be changed. The issue is whether the change of the rule of quantum probability assignment breaks relativistic causality. We have shown that Born rule on quantum measurement is derived by requiring relativistic causality condition. This shows how the relativistic causality limits the upper bound of quantum nonlocality through quantum probability assignment.

Decision making generalized by a cumulative probability weighting function

NASA Astrophysics Data System (ADS)

dos Santos, Lindomar Soares; Destefano, Natália; Martinez, Alexandre Souto

2018-01-01

Typical examples of intertemporal decision making involve situations in which individuals must choose between a smaller reward, but more immediate, and a larger one, delivered later. Analogously, probabilistic decision making involves choices between options whose consequences differ in relation to their probability of receiving. In Economics, the expected utility theory (EUT) and the discounted utility theory (DUT) are traditionally accepted normative models for describing, respectively, probabilistic and intertemporal decision making. A large number of experiments confirmed that the linearity assumed by the EUT does not explain some observed behaviors, as nonlinear preference, risk-seeking and loss aversion. That observation led to the development of new theoretical models, called non-expected utility theories (NEUT), which include a nonlinear transformation of the probability scale. An essential feature of the so-called preference function of these theories is that the probabilities are transformed by decision weights by means of a (cumulative) probability weighting function, w(p) . We obtain in this article a generalized function for the probabilistic discount process. This function has as particular cases mathematical forms already consecrated in the literature, including discount models that consider effects of psychophysical perception. We also propose a new generalized function for the functional form of w. The limiting cases of this function encompass some parametric forms already proposed in the literature. Far beyond a mere generalization, our function allows the interpretation of probabilistic decision making theories based on the assumption that individuals behave similarly in the face of probabilities and delays and is supported by phenomenological models.

Fishing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, G.

1984-09-01

Two classifications of fishing jobs are discussed: open hole and cased hole. When there is no casing in the area of the fish, it is called open hole fishing. When the fish is inside the casing, it is called cased hole fishing. The article lists various things that can become a fish-stuck drill pipe, including: broken drill pipe, drill collars, bit, bit cones, hand tools dropped in the well, sanded up or mud stuck tubing, packers become stuck, and much more. It is suggested that on a fishing job, all parties involved should cooperate with each other, and that fishingmore » tool people obtain all the information concerning the well. That way they can select the right tools and methods to clean out the well as quickly as possible.« less

Micro-structural characterization of precipitation-synthesized fluorapatite nano-material by transmission electron microscopy using different sample preparation techniques.

PubMed

Chinthaka Silva, G W; Ma, Longzhou; Hemmers, Oliver; Lindle, Dennis

2008-01-01

Fluorapatite is a naturally occurring mineral of the apatite group and it is well known for its high physical and chemical stability. There is a recent interest in this ceramic to be used as a radioactive waste form material due to its intriguing chemical and physical properties. In this study, the nano-sized fluorapatite particles were synthesized using a precipitation method and the material was characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Two well-known methods, called solution-drop and the microtome cutting, were used to prepare the sample for TEM analysis. It was found that the microtome cutting technique is advantageous for examining the particle shape and cross-sectional morphology as well as for obtaining ultra-thin samples. However, this method introduces artifacts and strong background contrast for high-resolution transmission electron microscopy (HRTEM) observation. On the other hand, phase image simulations showed that the solution-drop method is reliable and stable for HRTEM analysis. Therefore, in order to comprehensively analyze the microstructure and morphology of the nano-material, it is necessary to combine both solution-drop and microtome cutting techniques for TEM sample preparation.

Tears of Wine

NASA Astrophysics Data System (ADS)

Rathore, Prerana; Sharma, Vivek

`Tears of wine' refer to the rows of wine-drops that spontaneously emerge within a glass of strong wine. Evaporation-driven Marangoni flows near the meniscus of water-alcohol mixtures drive liquid upward forming a thin liquid film, and a rim or ridge forms near the moving contact line. Eventually the rim undergoes an instability forming drops, that roll back into bulk reservoir forming so called tears or legs of wine. Most studies in literature argue the evaporation of more volatile, lower surface tension component (alcohol) results in a concentration-dependent surface tension gradient that drives the climbing flow within the thin film. Though it is well-known that evaporative cooling can create temperature gradients that could provide additional contribution to the climbing flows, the role of thermocapillary flows is less well-understood. Furthermore, the patterns, flows and instabilities that occur near the rim, and determine the size and periodicity of tears, are not well-studied. Using experiments and theory, we visualize and analyze the formation and growth of tears of wine. The sliding drops, released from the rim towards the bulk reservoir, show oscillations and a cascade of fascinating flows that are analyzed for the first time.

Hangman's fracture: a historical and biomechanical perspective.

PubMed

Rayes, Mahmoud; Mittal, Monika; Rengachary, Setti S; Mittal, Sandeep

2011-02-01

The execution technique of hanging, introduced by the Angle, Saxon, and Jute Germanic tribes during their invasions of the Roman Empire and Britain in the 5th century, has remained largely unchanged over time. The earliest form of a gallows was a tree on which prisoners were hanged. Despite the introduction of several modifications such as a trap door, the main mechanism of death remained asphyxiation. This created the opportunity for attempted revival after the execution, and indeed several well-known cases of survival following judicial hanging have been reported. It was not until the introduction of the standard drop by Dr. Samuel Haughton in 1866, and the so-called long drop by William Marwood in 1872 that hanging became a standard, humane means to achieve instantaneous death. Hangmen, however, fearing knot slippage, started substituting the subaural knot for the traditional submental knot. Subaural knots were not as effective, and cases of decapitation were recorded. Standardization of the long drop was further propagated by John Berry, an executioner who used mathematical calculations to estimate the correct drop length for each individual to be hanged. A British committee on capital sentences, led by Lord Aberdare, studied the execution method, and advocated for the submental knot. However, it was not until Frederic Wood-Jones published his seminal work in 1913 that cervical fractures were identified as the main mechanism of death following hanging in which the long drop and a submental knot were used. Schneider introduced the term "hangman's fracture" in 1965, and reported on the biomechanics and other similarities of the cervical fractures seen following judicial hangings and those caused by motor vehicle accidents.

Optimal formation of genetically modified and functional pancreatic islet spheroids by using hanging-drop strategy.

PubMed

Kim, H J; Alam, Z; Hwang, J W; Hwang, Y H; Kim, M J; Yoon, S; Byun, Y; Lee, D Y

2013-03-01

Rejection and hypoxia are important factors causing islet loss at an early stage after pancreatic islet transplantation. Recently, islets have been dissociated into single cells for reaggregation into so-called islet spheroids. Herein, we used a hanging-drop strategy to form islet spheroids to achieve functional equivalence to intact islets. To obtain single islet cells, we dissociated islets with trypsin-EDTA digestion for 10 minutes. To obtain spheroids, we dropped various numbers of single cells (125, 250, or 500 cells/30 μL drop) onto a Petri dish, that was inverted for incubation in humidified air containing 5% CO(2) at 37 °C for 7 days. The aggregated spheroids in the droplets were harvested for further culture. The size of the aggregated islet spheroids depended on the number of single cells (125-500 cells/30 μL droplet). Their morphology was similar to that of intact islets without any cellular damage. When treated with various concentrations of glucose to evaluate responsiveness, their glucose-mediated stimulation index value was similar to that of intact islets, an observation that was attributed to strong cell-to-cell interactions in islet spheroids. However, islet spheroids aggregated in general culture dishes showed abnormal glucose responsiveness owing to weak cell-to-cell interactions. Cell-to-cell interactions in islet spheroids were confirmed with an anti-connexin-36 monoclonal antibody. Finally, nonviral poly(ethylene imine)-mediated interleukin-10 cytokine gene delivered beforehand into dissociated single cells before formation of islet spheroids increased the gene transfection efficacy and interleukin-10 secretion from islet spheroids >4-fold compared with intact islets. These results demonstrated the potential application of genetically modified, functional islet spheroids with of controlled size and morphology using an hanging-drop technique. Copyright © 2013 Elsevier Inc. All rights reserved.

Statistical contact angle analyses; "slow moving" drops on a horizontal silicon-oxide surface.

PubMed

Schmitt, M; Grub, J; Heib, F

2015-06-01

Sessile drop experiments on horizontal surfaces are commonly used to characterise surface properties in science and in industry. The advancing angle and the receding angle are measurable on every solid. Specially on horizontal surfaces even the notions themselves are critically questioned by some authors. Building a standard, reproducible and valid method of measuring and defining specific (advancing/receding) contact angles is an important challenge of surface science. Recently we have developed two/three approaches, by sigmoid fitting, by independent and by dependent statistical analyses, which are practicable for the determination of specific angles/slopes if inclining the sample surface. These approaches lead to contact angle data which are independent on "user-skills" and subjectivity of the operator which is also of urgent need to evaluate dynamic measurements of contact angles. We will show in this contribution that the slightly modified procedures are also applicable to find specific angles for experiments on horizontal surfaces. As an example droplets on a flat freshly cleaned silicon-oxide surface (wafer) are dynamically measured by sessile drop technique while the volume of the liquid is increased/decreased. The triple points, the time, the contact angles during the advancing and the receding of the drop obtained by high-precision drop shape analysis are statistically analysed. As stated in the previous contribution the procedure is called "slow movement" analysis due to the small covered distance and the dominance of data points with low velocity. Even smallest variations in velocity such as the minimal advancing motion during the withdrawing of the liquid are identifiable which confirms the flatness and the chemical homogeneity of the sample surface and the high sensitivity of the presented approaches. Copyright © 2014 Elsevier Inc. All rights reserved.

Probabilistic assessment methodology for continuous-type petroleum accumulations

USGS Publications Warehouse

Crovelli, R.A.

2003-01-01

The analytic resource assessment method, called ACCESS (Analytic Cell-based Continuous Energy Spreadsheet System), was developed to calculate estimates of petroleum resources for the geologic assessment model, called FORSPAN, in continuous-type petroleum accumulations. The ACCESS method is based upon mathematical equations derived from probability theory in the form of a computer spreadsheet system. ?? 2003 Elsevier B.V. All rights reserved.

Red-shouldered hawk broadcast surveys: Factors affecting detection of responses and population trends

USGS Publications Warehouse

McLeod, M.A.; Andersen, D.E.

1998-01-01

Forest-nesting raptors are often difficult to detect and monitor because they can be secretive, and their nests can be difficult to locate. Some species, however, respond to broadcasts of taped calls, and these responses may be useful both in monitoring population trends and in locating nests. We conducted broadcast surveys on roads and at active red-shouldered hawk (Buteo lineatus) nests in northcentral Minnesota to determine effects of type of call (conspecific or great horned owl [Bubo virginianus]), time of day, and phase of the breeding cycle on red-shouldered hawk response behavior and to evaluate usefulness of broadcasts as a population monitoring tool using area occupied-probability-of-detection techniques. During the breeding seasons of 1994 and 1995, we surveyed 4 10-station road transects 59 times and conducted 76 surveys at 24 active nests. Results of these surveys indicated conspecific calls broadcast prior to hatch and early in the day were the most effective method of detecting red-shouldered hawks. Probability of detection via conspecific calls averaged 0.25, and area occupied was 100%. Computer simulations using these field data indicated broadcast surveys have the potential to be used as a population monitoring tool.

Detailed statistical contact angle analyses; "slow moving" drops on inclining silicon-oxide surfaces.

PubMed

Schmitt, M; Groß, K; Grub, J; Heib, F

2015-06-01

Contact angle determination by sessile drop technique is essential to characterise surface properties in science and in industry. Different specific angles can be observed on every solid which are correlated with the advancing or the receding of the triple line. Different procedures and definitions for the determination of specific angles exist which are often not comprehensible or reproducible. Therefore one of the most important things in this area is to build standard, reproducible and valid methods for determining advancing/receding contact angles. This contribution introduces novel techniques to analyse dynamic contact angle measurements (sessile drop) in detail which are applicable for axisymmetric and non-axisymmetric drops. Not only the recently presented fit solution by sigmoid function and the independent analysis of the different parameters (inclination, contact angle, velocity of the triple point) but also the dependent analysis will be firstly explained in detail. These approaches lead to contact angle data and different access on specific contact angles which are independent from "user-skills" and subjectivity of the operator. As example the motion behaviour of droplets on flat silicon-oxide surfaces after different surface treatments is dynamically measured by sessile drop technique when inclining the sample plate. The triple points, the inclination angles, the downhill (advancing motion) and the uphill angles (receding motion) obtained by high-precision drop shape analysis are independently and dependently statistically analysed. Due to the small covered distance for the dependent analysis (<0.4mm) and the dominance of counted events with small velocity the measurements are less influenced by motion dynamics and the procedure can be called "slow moving" analysis. The presented procedures as performed are especially sensitive to the range which reaches from the static to the "slow moving" dynamic contact angle determination. They are characterised by small deviations of the computed values. Additional to the detailed introduction of this novel analytical approaches plus fit solution special motion relations for the drop on inclined surfaces and detailed relations about the reactivity of the freshly cleaned silicon wafer surface resulting in acceleration behaviour (reactive de-wetting) are presented. Copyright © 2014 Elsevier Inc. All rights reserved.

Investigation of the cold drops in the European area, study based on ERA Interim and ECMWF ensemble model

NASA Astrophysics Data System (ADS)

Gaal, Nikolett; Ihasz, Istvan

2013-04-01

We aimed to analyze the cold drops and the upper level lows formed in the middle troposphere - which are often difficult to be predicted - by means of the statistical methods and case studies. Cold drops are often followed by intensive events such as heavy rainfall, rainstorm, at times tubas and non mesocyclonical tornadoes. Due to the above mentioned events and the incentive of Aviation and Severe Weather Forecasting Division at Hungarian Meteorological Service, the phenomenon was analyzed in a complex way by a self-developed multiple method. Upper-Level Lows (ULL-s) are closed; cyclonically circulating eddies isolated from the main western stream in the middle and upper troposphere. They are also sometimes called "cold drops" because the air within an Upper Level low is colder than in its surroundings. The cold air within usually does not show up on the surface, meaning the vertical temperature gradient is high, which in turn causes instability and heavy storms, especially during the summer. An ULL-s diameter is about a couple hundred km-s, so it looks like a miniature cyclone. ERA INTERIM is the current state of reanalysis that is still in development. It also has the best possible spatial resolution, which leads to its usage in a wide area of fields. Our studies focused mainly on the cold drops' statistics and meteorology, as well as a few case studies. Since ULL's occur rarely, we developed a new ULL-recognition process to increase the number of samples available. First of all, we gathered 70days when cold drops occurred in the past 10 years. Then we analyzed them in 6-hour periods, for a total of 280 separate time periods. Finally, we have four main case studies in the paper. In the future, we would like to run further tests with our ULL-recognition algorithm to study the last 30 years of cold drops, and we would also like to experiment more with ULL forecasting as well.

Accurate recapture identification for genetic mark–recapture studies with error-tolerant likelihood-based match calling and sample clustering

USGS Publications Warehouse

Sethi, Suresh; Linden, Daniel; Wenburg, John; Lewis, Cara; Lemons, Patrick R.; Fuller, Angela K.; Hare, Matthew P.

2016-01-01

Error-tolerant likelihood-based match calling presents a promising technique to accurately identify recapture events in genetic mark–recapture studies by combining probabilities of latent genotypes and probabilities of observed genotypes, which may contain genotyping errors. Combined with clustering algorithms to group samples into sets of recaptures based upon pairwise match calls, these tools can be used to reconstruct accurate capture histories for mark–recapture modelling. Here, we assess the performance of a recently introduced error-tolerant likelihood-based match-calling model and sample clustering algorithm for genetic mark–recapture studies. We assessed both biallelic (i.e. single nucleotide polymorphisms; SNP) and multiallelic (i.e. microsatellite; MSAT) markers using a combination of simulation analyses and case study data on Pacific walrus (Odobenus rosmarus divergens) and fishers (Pekania pennanti). A novel two-stage clustering approach is demonstrated for genetic mark–recapture applications. First, repeat captures within a sampling occasion are identified. Subsequently, recaptures across sampling occasions are identified. The likelihood-based matching protocol performed well in simulation trials, demonstrating utility for use in a wide range of genetic mark–recapture studies. Moderately sized SNP (64+) and MSAT (10–15) panels produced accurate match calls for recaptures and accurate non-match calls for samples from closely related individuals in the face of low to moderate genotyping error. Furthermore, matching performance remained stable or increased as the number of genetic markers increased, genotyping error notwithstanding.

On splice site prediction using weight array models: a comparison of smoothing techniques

NASA Astrophysics Data System (ADS)

Taher, Leila; Meinicke, Peter; Morgenstern, Burkhard

2007-11-01

In most eukaryotic genes, protein-coding exons are separated by non-coding introns which are removed from the primary transcript by a process called "splicing". The positions where introns are cut and exons are spliced together are called "splice sites". Thus, computational prediction of splice sites is crucial for gene finding in eukaryotes. Weight array models are a powerful probabilistic approach to splice site detection. Parameters for these models are usually derived from m-tuple frequencies in trusted training data and subsequently smoothed to avoid zero probabilities. In this study we compare three different ways of parameter estimation for m-tuple frequencies, namely (a) non-smoothed probability estimation, (b) standard pseudo counts and (c) a Gaussian smoothing procedure that we recently developed.

Further delineation of Nevo syndrome.

PubMed Central

al-Gazali, L I; Bakalinova, D; Varady, E; Scorer, J; Nork, M

1997-01-01

Nevo syndrome is an autosomal recessive syndrome characterised by prenatal overgrowth, joint laxity, kyphosis, wrist drop, spindle shaped fingers, and volar oedema. Four children from two families have been reported previously. We report two further children from two unrelated Arab families from two different tribes. Both presented at birth with hypotonia, joint laxity, kyphosis, wrist drop, spindle shaped fingers, and volar oedema. Both have delayed motor development at the ages of 2 years 10 months and 3 months respectively. Cognitive development is normal in one, and the other case appears to be developing normally at 3 months of age. One has, in addition, a wide spinal canal on MRI of the spine indicating some degree of dural ectasia. This report brings the total number of children reported with this syndrome to six from four families; three of these families are Arab. This indicates that the gene for this syndrome is probably commoner in Arabs than in other populations. Images PMID:9152832

Modification of Lightweight Aggregates' Microstructure by Used Motor Oil Addition.

PubMed

Franus, Małgorzata; Jozefaciuk, Grzegorz; Bandura, Lidia; Lamorski, Krzysztof; Hajnos, Mieczysław; Franus, Wojciech

2016-10-18

An admixture of lightweight aggregate substrates (beidellitic clay containing 10 wt % of natural clinoptilolite or Na-P1 zeolite) with used motor oil (1 wt %-8 wt %) caused marked changes in the aggregates' microstructure, measured by a combination of mercury porosimetry (MIP), microtomography (MT), and scanning electron microscopy. Maximum porosity was produced at low (1%-2%) oil concentrations and it dropped at higher concentrations, opposite to the aggregates' bulk density. Average pore radii, measured by MIP, decreased with an increasing oil concentration, whereas larger (MT) pore sizes tended to increase. Fractal dimension, derived from MIP data, changed similarly to the MIP pore radius, while that derived from MT remained unaltered. Solid phase density, measured by helium pycnometry, initially dropped slightly and then increased with the amount of oil added, which was most probably connected to changes in the formation of extremely small closed pores that were not available for He atoms.

Identifying potential dropouts from college physics classes

NASA Astrophysics Data System (ADS)

Wollman, Warren; Lawrenz, Frances

Hudson and Rottman (1981) established that mathematics ability is probably a secondary factor influencing dropout from college physics courses. Other factors remain to be found for predicting who will drop out or at least have difficulty with the course. When mathematics ability is coupled with general indicators of performance (total GPA and ACT natural science), prediction of performance for those who complete the course is substantially improved. Moreover, discriminant analyses reveal who will have at least some difficulty, but not who will drop out. The problem of isolating specific weaknesses of students who have difficulty persists. Physics achievement appears to depend on mathematics ability only to the extent that students possess the ability to utilize mathematics knowledge for solving physics problems. Identification of the specific aspects of this ability as well as the specific deficiencies leading to dropout should be the object of future research. For the present, interviews might be more revealing than group testing methods.

Modification of Lightweight Aggregates’ Microstructure by Used Motor Oil Addition

PubMed Central

Franus, Małgorzata; Jozefaciuk, Grzegorz; Bandura, Lidia; Lamorski, Krzysztof; Hajnos, Mieczysław; Franus, Wojciech

2016-01-01

An admixture of lightweight aggregate substrates (beidellitic clay containing 10 wt % of natural clinoptilolite or Na-P1 zeolite) with used motor oil (1 wt %–8 wt %) caused marked changes in the aggregates’ microstructure, measured by a combination of mercury porosimetry (MIP), microtomography (MT), and scanning electron microscopy. Maximum porosity was produced at low (1%–2%) oil concentrations and it dropped at higher concentrations, opposite to the aggregates’ bulk density. Average pore radii, measured by MIP, decreased with an increasing oil concentration, whereas larger (MT) pore sizes tended to increase. Fractal dimension, derived from MIP data, changed similarly to the MIP pore radius, while that derived from MT remained unaltered. Solid phase density, measured by helium pycnometry, initially dropped slightly and then increased with the amount of oil added, which was most probably connected to changes in the formation of extremely small closed pores that were not available for He atoms. PMID:28773964

Amphiphilic nanoparticles suppress droplet break-up in a concentrated emulsion flowing through a narrow constriction

PubMed Central

Gai, Ya; Kim, Minkyu; Pan, Ming; Tang, Sindy K. Y.

2017-01-01

This paper describes the break-up behavior of a concentrated emulsion comprising drops stabilized by amphiphilic silica nanoparticles flowing in a tapered microchannel. Such geometry is often used in serial droplet interrogation and sorting processes in droplet microfluidics applications. When exposed to high viscous stresses, drops can undergo break-up and compromise their physical integrity. As these drops are used as micro-reactors, such compromise leads to a loss in the accuracy of droplet-based assays. Here, we show droplet break-up is suppressed by replacing the fluoro-surfactant similar to the one commonly used in current droplet microfluidics applications with amphiphilic nanoparticles as droplet stabilizer. We identify parameters that influence the break-up of these drops and demonstrate that break-up probability increases with increasing capillary number and confinement, decreasing nanoparticle size, and is insensitive to viscosity ratio within the range tested. Practically, our results reveal two key advantages of nanoparticles with direct applications to droplet microfluidics. First, replacing surfactants with nanoparticles suppresses break-up and increases the throughput of the serial interrogation process to 3 times higher than that in surfactant system under similar flow conditions. Second, the insensitivity of break-up to droplet viscosity makes it possible to process samples having different composition and viscosities without having to change the channel and droplet geometry in order to maintain the same degree of break-up and corresponding assay accuracy. PMID:28652887

Spatial probability of soil water repellency in an abandoned agricultural field in Lithuania

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Misiūnė, Ieva

2015-04-01

Water repellency is a natural soil property with implications on infiltration, erosion and plant growth. It depends on soil texture, type and amount of organic matter, fungi, microorganisms, and vegetation cover (Doerr et al., 2000). Human activities as agriculture can have implications on soil water repellency (SWR) due tillage and addition of organic compounds and fertilizers (Blanco-Canqui and Lal, 2009; Gonzalez-Penaloza et al., 2012). It is also assumed that SWR has a high small-scale variability (Doerr et al., 2000). The aim of this work is to study the spatial probability of SWR in an abandoned field testing several geostatistical methods, Organic Kriging (OK), Simple Kriging (SK), Indicator Kriging (IK), Probability Kriging (PK) and Disjunctive Kriging (DK). The study area it is located near Vilnius urban area at (54 49' N, 25 22', 104 masl) in Lithuania (Pereira and Oliva, 2013). It was designed a experimental plot with 21 m2 (07x03 m). Inside this area it was measured SWR was measured every 50 cm using the water drop penetration time (WDPT) (Wessel, 1998). A total of 105 points were measured. The probability of SWR was classified in 0 (No probability) to 1 (High probability). The methods accuracy was assessed with the cross validation method. The best interpolation method was the one with the lowest Root Mean Square Error (RMSE). The results showed that the most accurate probability method was SK (RMSE=0.436), followed by DK (RMSE=0.437), IK (RMSE=0.448), PK (RMSE=0.452) and OK (RMSE=0.537). Significant differences were identified among probability tests (Kruskal-Wallis test =199.7597 p<0.001). On average the probability of SWR was high with the OK (0.58±0.08) followed by PK (0.49±0.18), SK (0.32±0.16), DK (0.32±0.15) and IK (0.31±0.16). The most accurate probability methods predicted a lower probability of SWR in the studied plot. The spatial distribution of SWR was different according to the tested technique. Simple Kriging, DK, IK and PK methods identified the high SWR probabilities in the northeast and central part of the plot, while OK observed mainly in the south-western part of the plot. In conclusion, before predict the spatial probability of SWR it is important to test several methods in order to identify the most accurate. Acknowledgments COST action ES1306 (Connecting European connectivity research). References Blanco-Canqui, H., Lal, R. (2009) Extend of water repellency under long-term no-till soils. Geoderma, 149, 171-180. Doerr, S.H., Shakesby, R.A., Walsh, R.P.D. (2000) Soil water repellency: Its causes, characteristics and hydro-geomorphological significance. Earth-Science Reviews, 51, 33-65. Gonzalez-Penaloza, F.A., Cerda, A., Zavala, L.M., Jordan, A., Gimenez-Morera, A., Arcenegui, V. (2012) Do conservative agriculture practices increase soil water repellency? A case study in citrus-croped soils. Soil and Tillage Research, 124, 233-239. Pereira, P., Oliva, M. (2013) Modelling soil water repellency in an abandoned agricultural field, Visnyk Geology, Visnyk Geology 4, 77-80. Wessel, A.T. (1988) On using the effective contact angle and the water drop penetration time for classification of water repellency in dune soils. Earth Surface Process and Landforms, 13, 555-265.

Mount St. Helens Project. Cowlitz River Levee Systems, 2009 Level of Flood Protection Update Summary

DTIC Science & Technology

2010-02-04

bed channel, where ripples, dunes , washed out dunes , and antidunes are possible. It is not, however, appropriate to describe a gravel bed channel in...For more frequent events the bedform is generally in lower regime dunes or plane bed. However, the probability of levee failure below 10 percent...from dunes (lower regime) to upper regime (washed out dunes ) the roughness value drops precipitously. A discussion in ASCE (2009) suggests that

Design of distributed JT (Joule-Thomson) effect heat exchanger for superfluid 2 K cooling device

NASA Astrophysics Data System (ADS)

Jeong, S.; Park, C.; Kim, K.

2018-03-01

Superfluid at 2 K or below is readily obtained from liquid helium at 4.2 K by reducing its vapour pressure. For better cooling performance, however, the cold energy of vaporized helium at 2 K chamber can be effectively utilized in a recuperator which is specially designed in this paper for accomplishing so-called the distributed Joule-Thomson (JT) expansion effect. This paper describes the design methodology of distributed JT effect heat exchanger for 2 K JT cooling device. The newly developed heat exchanger allows continuous significant pressure drop at high-pressure part of the recuperative heat exchanger by using a capillary tube. Being different from conventional recuperative heat exchangers, the efficient JT effect HX must consider the pressure drop effect as well as the heat transfer characteristic. The heat exchanger for the distributed JT effect actively utilizes continuous pressure loss at the hot stream of the heat exchanger by using an OD of 0.64 mm and an ID of 0.4 mm capillary tube. The analysis is performed by dividing the heat exchanger into the multiple sub-units of the heat exchange part and JT valve. For more accurate estimation of the pressure drop of spirally wound capillary tube, preliminary experiments are carried out to investigate the friction factor at high Reynolds number. By using the developed pressure drop correlation and the heat transfer correlation, the specification of the heat exchanger with distributed JT effect for 2 K JT refrigerator is determined.

Fission properties of Po isotopes in different macroscopic-microscopic models

NASA Astrophysics Data System (ADS)

Bartel, J.; Pomorski, K.; Nerlo-Pomorska, B.; Schmitt, Ch

2015-11-01

Fission-barrier heights of nuclei in the Po isotopic chain are investigated in several macroscopic-microscopic models. Using the Yukawa-folded single-particle potential, the Lublin-Strasbourg drop (LSD) model, the Strutinsky shell-correction method to yield the shell corrections and the BCS theory for the pairing contributions, fission-barrier heights are calculated and found in quite good agreement with the experimental data. This turns out, however, to be only the case when the underlying macroscopic, liquid-drop (LD) type, theory is well chosen. Together with the LSD approach, different LD parametrizations proposed by Moretto et al are tested. Four deformation parameters describing respectively elongation, neck-formation, reflectional-asymmetric, and non-axiality of the nuclear shape thus defining the so called modified Funny Hills shape parametrization are used in the calculation. The present study clearly demonstrates that nuclear fission-barrier heights constitute a challenging and selective tool to discern between such different macroscopic approaches.

An acoustical bubble counter for superheated drop detectors.

PubMed

Taylor, Chris; Montvila, Darius; Flynn, David; Brennan, Christopher; d'Errico, Francesco

2006-01-01

A new bubble counter has been developed based on the well-established approach of detecting vaporization events acoustically in superheated drop detectors (SDDs). This counter is called the Framework Scientific ABC 1260, and it represents a major improvement over prior versions of this technology. By utilizing advanced acoustic pattern recognition software, the bubble formation event can be differentiated from ambient background noise, as well as from other acoustic signatures. Additional structural design enhancements include a relocation of the electronic components to the bottom of the device; thus allowing for greater stability, easier access to vial SDDs without exposure to system electronics. Upgrades in the electronics permit an increase in the speed of bubble detection by almost 50%, compared with earlier versions of the counters. By positioning the vial on top of the device, temperature and sound insulation can be accommodated for extreme environments. Lead shells can also be utilized for an enhanced response to high-energy neutrons.

Railway crossing risk area detection using linear regression and terrain drop compensation techniques.

PubMed

Chen, Wen-Yuan; Wang, Mei; Fu, Zhou-Xing

2014-06-16

Most railway accidents happen at railway crossings. Therefore, how to detect humans or objects present in the risk area of a railway crossing and thus prevent accidents are important tasks. In this paper, three strategies are used to detect the risk area of a railway crossing: (1) we use a terrain drop compensation (TDC) technique to solve the problem of the concavity of railway crossings; (2) we use a linear regression technique to predict the position and length of an object from image processing; (3) we have developed a novel strategy called calculating local maximum Y-coordinate object points (CLMYOP) to obtain the ground points of the object. In addition, image preprocessing is also applied to filter out the noise and successfully improve the object detection. From the experimental results, it is demonstrated that our scheme is an effective and corrective method for the detection of railway crossing risk areas.

Railway Crossing Risk Area Detection Using Linear Regression and Terrain Drop Compensation Techniques

PubMed Central

Chen, Wen-Yuan; Wang, Mei; Fu, Zhou-Xing

2014-01-01

Most railway accidents happen at railway crossings. Therefore, how to detect humans or objects present in the risk area of a railway crossing and thus prevent accidents are important tasks. In this paper, three strategies are used to detect the risk area of a railway crossing: (1) we use a terrain drop compensation (TDC) technique to solve the problem of the concavity of railway crossings; (2) we use a linear regression technique to predict the position and length of an object from image processing; (3) we have developed a novel strategy called calculating local maximum Y-coordinate object points (CLMYOP) to obtain the ground points of the object. In addition, image preprocessing is also applied to filter out the noise and successfully improve the object detection. From the experimental results, it is demonstrated that our scheme is an effective and corrective method for the detection of railway crossing risk areas. PMID:24936948

Bubble migration inside a liquid drop in a space laboratory

NASA Technical Reports Server (NTRS)

Annamalai, P.; Shankar, N.; Cole, R.; Subramanian, R. S.

1982-01-01

The design of experiments in materials processing for trials on board the Shuttle are described. Thermocapillary flows will be examined as an aid to mixing in the formation of glasses. Acoustically levitated molten glass spheres will be spot heated to induce surface flow away from the hot spot to induce mixing. The surface flows are also expected to cause internal convective motion which will drive entrained gas bubbles toward the hot spot, a process also enhanced by the presence of thermal gradients. The method is called fining, and will be augmented by rotation of the sphere to cause bubble migration toward the axes of rotation to form one large bubble which is more easily removed. Centering techniques to fix the maximum centering accuracy will also be tried. Ground-based studies of bubble migration in a rotating liquid and in a temperature gradient in a liquid drop are reviewed.

Scared and less noisy: glucocorticoids are associated with alarm call entropy

PubMed Central

Blumstein, Daniel T.; Chi, Yvonne Y.

2012-01-01

The nonlinearity and arousal hypothesis predicts that highly aroused mammals will produce nonlinear, noisy vocalizations. We tested this prediction by measuring faecal glucocorticoid metabolites (GCMs) in adult yellow-bellied marmots (Marmota flaviventris), and asking if variation in GCMs was positively correlated with Wiener entropy—a measure of noise. Contrary to our prediction, we found a significant negative relationship: marmots with more faecal GCMs produced calls with less noise than those with lower levels of GCMs. A previous study suggested that glucocorticoids modulate the probability that a marmot will emit a call. This study suggests that, like some other species, calls emitted from highly aroused individuals are less noisy. Glucocorticoids thus play an important, yet underappreciated role, in alarm call production. PMID:21976625

Scared and less noisy: glucocorticoids are associated with alarm call entropy.

PubMed

Blumstein, Daniel T; Chi, Yvonne Y

2012-04-23

The nonlinearity and arousal hypothesis predicts that highly aroused mammals will produce nonlinear, noisy vocalizations. We tested this prediction by measuring faecal glucocorticoid metabolites (GCMs) in adult yellow-bellied marmots (Marmota flaviventris), and asking if variation in GCMs was positively correlated with Wiener entropy-a measure of noise. Contrary to our prediction, we found a significant negative relationship: marmots with more faecal GCMs produced calls with less noise than those with lower levels of GCMs. A previous study suggested that glucocorticoids modulate the probability that a marmot will emit a call. This study suggests that, like some other species, calls emitted from highly aroused individuals are less noisy. Glucocorticoids thus play an important, yet underappreciated role, in alarm call production.

Modeling rural landowners' hunter access policies in East Texas, USA

NASA Astrophysics Data System (ADS)

Wright, Brett A.; Fesenmaier, Daniel R.

1988-03-01

Private landowners in East Texas, USA, were aggregated into one of four policy categories according to the degree of access allowed to their lands for hunting. Based on these categories, a logistic regression model of possible determinants of access policy was developed and probabilities of policy adoption were calculated. Overwhelmingly, attitudes toward hunting as a sport, incentives, and control over the actions of hunters were most predictive of landowners' policies. Additionally, the availability of deer was found to be negatively correlated with access, thereby suggesting management efforts to increase deer populations may be counter to increasing access. Further, probabilities derived from the model indicated that there was almost a 7 in 10 chance (0.66) that landowners would adopt policies commensurate with allowing family and personal acquaintances to hunt on their property. However, the probability of increasing access beyond this level, where access was provided for the general public, dropped off drastically to less than 5% (0.04).

Influence of atmospheric properties on detection of wood-warbler nocturnal flight calls

NASA Astrophysics Data System (ADS)

Horton, Kyle G.; Stepanian, Phillip M.; Wainwright, Charlotte E.; Tegeler, Amy K.

2015-10-01

Avian migration monitoring can take on many forms; however, monitoring active nocturnal migration of land birds is limited to a few techniques. Avian nocturnal flight calls are currently the only method for describing migrant composition at the species level. However, as this method develops, more information is needed to understand the sources of variation in call detection. Additionally, few studies examine how detection probabilities differ under varying atmospheric conditions. We use nocturnal flight call recordings from captive individuals to explore the dependence of flight call detection on atmospheric temperature and humidity. Height or distance from origin had the largest influence on call detection, while temperature and humidity also influenced detectability at higher altitudes. Because flight call detection varies with both atmospheric conditions and flight height, improved monitoring across time and space will require correction for these factors to generate standardized metrics of songbird migration.

Unmodeled observation error induces bias when inferring patterns and dynamics of species occurrence via aural detections

USGS Publications Warehouse

McClintock, Brett T.; Bailey, Larissa L.; Pollock, Kenneth H.; Simons, Theodore R.

2010-01-01

The recent surge in the development and application of species occurrence models has been associated with an acknowledgment among ecologists that species are detected imperfectly due to observation error. Standard models now allow unbiased estimation of occupancy probability when false negative detections occur, but this is conditional on no false positive detections and sufficient incorporation of explanatory variables for the false negative detection process. These assumptions are likely reasonable in many circumstances, but there is mounting evidence that false positive errors and detection probability heterogeneity may be much more prevalent in studies relying on auditory cues for species detection (e.g., songbird or calling amphibian surveys). We used field survey data from a simulated calling anuran system of known occupancy state to investigate the biases induced by these errors in dynamic models of species occurrence. Despite the participation of expert observers in simplified field conditions, both false positive errors and site detection probability heterogeneity were extensive for most species in the survey. We found that even low levels of false positive errors, constituting as little as 1% of all detections, can cause severe overestimation of site occupancy, colonization, and local extinction probabilities. Further, unmodeled detection probability heterogeneity induced substantial underestimation of occupancy and overestimation of colonization and local extinction probabilities. Completely spurious relationships between species occurrence and explanatory variables were also found. Such misleading inferences would likely have deleterious implications for conservation and management programs. We contend that all forms of observation error, including false positive errors and heterogeneous detection probabilities, must be incorporated into the estimation framework to facilitate reliable inferences about occupancy and its associated vital rate parameters.

Dynamical manifestations of quantum chaos

NASA Astrophysics Data System (ADS)

Torres Herrera, Eduardo Jonathan; Santos, Lea

2017-04-01

A main feature of a chaotic quantum system is a rigid spectrum, where the levels do not cross. Dynamical quantities, such as the von Neumann entanglement entropy, Shannon information entropy, and out-of-time correlators can differentiate the ergodic from the nonergodic phase in disordered interacting systems, but not level repulsion from level crossing in the delocalized phase of disordered and clean models. This is in contrast with the long-time evolution of the survival probability of the initial state. The onset of correlated energy levels is manifested by a drop, referred to as correlation hole, below the asymptotic value of the survival probability. The correlation hole is an unambiguous indicator of the presence of level repulsion. EJTH is grateful to VIEP, BUAP for financial support through the VIEP projects program.

Lacosamide

MedlinePlus

... with other medications to control certain types of seizures. Lacosamide is in a class of medications called ... mood. If you suddenly stop taking lacosamide, your seizures may happen more often. Your doctor will probably ...

Pairing call-response surveys and distance sampling for a mammalian carnivore

USGS Publications Warehouse

Hansen, Sara J. K.; Frair, Jacqueline L.; Underwood, Harold B.; Gibbs, James P.

2015-01-01

Density estimates accounting for differential animal detectability are difficult to acquire for wide-ranging and elusive species such as mammalian carnivores. Pairing distance sampling with call-response surveys may provide an efficient means of tracking changes in populations of coyotes (Canis latrans), a species of particular interest in the eastern United States. Blind field trials in rural New York State indicated 119-m linear error for triangulated coyote calls, and a 1.8-km distance threshold for call detectability, which was sufficient to estimate a detection function with precision using distance sampling. We conducted statewide road-based surveys with sampling locations spaced ≥6 km apart from June to August 2010. Each detected call (be it a single or group) counted as a single object, representing 1 territorial pair, because of uncertainty in the number of vocalizing animals. From 524 survey points and 75 detections, we estimated the probability of detecting a calling coyote to be 0.17 ± 0.02 SE, yielding a detection-corrected index of 0.75 pairs/10 km2 (95% CI: 0.52–1.1, 18.5% CV) for a minimum of 8,133 pairs across rural New York State. Importantly, we consider this an index rather than true estimate of abundance given the unknown probability of coyote availability for detection during our surveys. Even so, pairing distance sampling with call-response surveys provided a novel, efficient, and noninvasive means of monitoring populations of wide-ranging and elusive, albeit reliably vocal, mammalian carnivores. Our approach offers an effective new means of tracking species like coyotes, one that is readily extendable to other species and geographic extents, provided key assumptions of distance sampling are met.

The breeding behaviour, advertisement call and tadpole of Limnonectes dabanus (Anura: Dicroglossidae).

PubMed

Rowley, Jodi J L; Le, Duong Thi Thuy; Hoang, Huy Duc; Altig, Ronald

2014-11-04

Fanged frogs (Limnonectes) are a group of dicroglossid frogs from Asia that often have reversed sexual dimorphism with larger males. Limnonectes dabanus is a poorly known species of fanged frog from forested habitats in southern Vietnam and eastern Cambodia. Adult males exhibit an extreme degree of megacephaly and possess bizarre head ornamentation. L. dabanus breeds in shallow, non-flowing or very slow-flowing pools, puddles, and drainage ditches. Eggs are laid as a widely spaced array, and the larvae have a morphology typical of pond-dwelling tadpoles. Although males of the species lack vocal sacs, they produce a low-pitched (0.4-0.6 kHz), single-note advertisement call that sounds like a drop of water falling into water. Given the spacing of calling males, presence of multiple females near breeding sites, and reversed sexual dimorphism, the mating system of L. dabanus may be an example of resource-defense polygyny, and the massive head of the male is likely used in male combat.

Mid-IR Spectra Herbig Ae/Be Stars

NASA Technical Reports Server (NTRS)

Wooden, Diane; Witteborn, Fred C. (Technical Monitor)

1997-01-01

Herbig Ae/Be stars are intermediate mass pre-main sequence stars, the higher mass analogues to the T Tauri stars. Because of their higher mass, they are expected form more rapidly than the T Tauri stars. Whether the Herbig Ae/Be stars accrete only from collapsing infalling envelopes or whether accrete through geometrically flattened viscous accretion disks is of current debate. When the Herbig Ae/Be stars reach the main sequence they form a class called Vega-like stars which are known from their IR excesses to have debris disks, such as the famous beta Pictoris. The evolutionary scenario between the pre-main sequence Herbig Ae/Be stars and the main sequence Vega-like stars is not yet revealed and it bears on the possibility of the presence of Habitable Zone planets around the A stars. Photometric studies of Herbig Ae/Be stars have revealed that most are variable in the optical, and a subset of stars show non-periodic drops of about 2 magnitudes. These drops in visible light are accompanied by changes in their colors: at first the starlight becomes reddened, and then it becomes bluer, the polarization goes from less than 0.1 % to roughly 1% during these minima. The theory postulated by V. Grinnin is that large cometary bodies on highly eccentric orbits occult the star on their way to being sublimed, for systems that are viewed edge-on. This theory is one of several controversial theories about the nature of Herbig Ae/Be stars. A 5 year mid-IR spectrophotometric monitoring campaign was begun by Wooden and Butner in 1992 to look for correlations between the variations in visible photometry and mid-IR dust emission features. Generally the approximately 20 stars that have been observed by the NASA Ames HIFOGS spectrometer have been steady at 10 microns. There are a handful, however, that have shown variable mid-IR spectra, with 2 showing variations in both the continuum and features anti-correlated with visual photometry, and 3 showing variations in the emission features only while the continuum level remained unchanged. The first 2 stars mentioned probably have reprocessing envelopes. The other 3 stars gives important clues to the controversy over the geometry of the gas and dust around these pre-main sequence stars: the steady underlying 10 microns continuum and variable features indicates that an optically thick continuum probably arising from an accretion disk is decoupled from the optically thin emission features which may arise in a disk atmosphere. Bernadette Rodgers has joined this monitoring campaign in the near-IR using GRIMII with the goal of detecting variations in the hot dust continuum and the gas density in the dense accretion region close to these stars.

A GRASS GIS Semi-Stochastic Model for Evaluating the Probability of Landslides Impacting Road Networks in Collazzone, Central Italy

NASA Astrophysics Data System (ADS)

Taylor, Faith E.; Santangelo, Michele; Marchesini, Ivan; Malamud, Bruce D.

2013-04-01

During a landslide triggering event, the tens to thousands of landslides resulting from the trigger (e.g., earthquake, heavy rainfall) may block a number of sections of the road network, posing a risk to rescue efforts, logistics and accessibility to a region. Here, we present initial results from a semi-stochastic model we are developing to evaluate the probability of landslides intersecting a road network and the network-accessibility implications of this across a region. This was performed in the open source GRASS GIS software, where we took 'model' landslides and dropped them on a 79 km2 test area region in Collazzone, Umbria, Central Italy, with a given road network (major and minor roads, 404 km in length) and already determined landslide susceptibilities. Landslide areas (AL) were randomly selected from a three-parameter inverse gamma probability density function, consisting of a power-law decay of about -2.4 for medium and large values of AL and an exponential rollover for small values of AL; the rollover (maximum probability) occurs at about AL = 400 m.2 The number of landslide areas selected for each triggered event iteration was chosen to have an average density of 1 landslide km-2, i.e. 79 landslide areas chosen randomly for each iteration. Landslides were then 'dropped' over the region semi-stochastically: (i) random points were generated across the study region; (ii) based on the landslide susceptibility map, points were accepted/rejected based on the probability of a landslide occurring at that location. After a point was accepted, it was assigned a landslide area (AL) and length to width ratio. Landslide intersections with roads were then assessed and indices such as the location, number and size of road blockage recorded. The GRASS-GIS model was performed 1000 times in a Monte-Carlo type simulation. Initial results show that for a landslide triggering event of 1 landslide km-2 over a 79 km2 region with 404 km of road, the number of road blockages ranges from 6 to 17, resulting in one road blockage every 24-67 km of roads. The average length of road blocked was 33 m. As we progress with model development and more sophisticated network analysis, we believe this semi-stochastic modelling approach will aid civil protection agencies to get a rough idea for the probability of road network potential damage (road block number and extent) as the result of different magnitude landslide triggering event scenarios.

Operation characteristic of a heat pump of mechanical vapor recompression propelled by fans and its performance analysis applied to waste-water treatment

NASA Astrophysics Data System (ADS)

Weike, Pang; Wenju, Lin; Qilin, Pan; Wenye, Lin; Qunte, Dai; Luwei, Yang; Zhentao, Zhang

2014-01-01

In this paper, a set of heat pump (called as Mechanical Vapor Recompression, MVR) propelled by a centrifugal fan is tested and it shows some special characteristic when it works together with a falling film evaporator. Firstly, an analysis of the fan's suction and discharge parameters at stable state, such as its pressure and temperature, indicates that a phenomenon of wet compression is probably to appear during vapor compression. As a result, superheat after saturated vapor is compressed is eliminated, which reduces discharge temperature of the system. It is because drops boil away and absorb the super heat into their latent heat during vapor compression. Meanwhile, drops in the suction vapor add to the compressed vapor, which increase the given heat of the MVR heat pump. Next, assistant electric heat could adjust and keep steady of the operating pressure and temperature of an MVR heat pump. With the evaporation temperature up to be high, heat balance is broken and supplement heat needs to increase. Thirdly, the performance of an MVR heat pump is affect by the balance of falling film and evaporation that has an effect on heat transfer. Then, two parameters standing for the performance are measured as it runs in practical condition. The two important parameters are consumptive electricity power and productive water capacity. According to theoretical work in ideal condition by calculation and fan's input power by measure as running, adiabatic efficiency (ηad) of a centrifugal fan is calculated when it is applied in a heat pump of MVR. Following, based on ηad, practical SMER and COP of an MVR heat pump are discovered to be correlative with it. Finally, in dependence on productive water in theory and in practice, displacement efficiency (ηv) of centrifugal fans is obtained when compressing vapor, and so provide some references of matching a fan for an MVR heat pump. On the other hand, it is helpful to research and develop MVR heat pumps, and also to check electricity power consumption while operating practically in light of electric motor efficiency (ηe) and ηad.

Oxytocin Injection

MedlinePlus

... with other medications or procedures to end a pregnancy. Oxytocin is in a class of medications called ... the cervix, or toxemia (high blood pressure during pregnancy). Your doctor will probably not give you oxytocin ...

Synchronization Analysis of Master-Slave Probabilistic Boolean Networks.

PubMed

Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W C; Cao, Jinde

2015-08-28

In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results.

Synchronization Analysis of Master-Slave Probabilistic Boolean Networks

PubMed Central

Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W. C.; Cao, Jinde

2015-01-01

In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results. PMID:26315380

DOE Office of Scientific and Technical Information (OSTI.GOV)

Renaut, R.W.; Owen, R.B.

An unusual group of cherts found at saline, alkaline Lake Bogoria in the Kenya Rift differs from the Magadi-type cherts commonly associated with saline, alkaline lakes. The cherts are opaline, rich in diatoms, and formed from a siliceous, probably gelatinous, precursor that precipitated around submerged alkaline hot springs during a Holocene phase of high lake level. Silica precipitation resulted from rapid drop in the temperature of the spring waters and, possibly, pH. Lithification began before subaerial exposure. Ancient analogous cherts are likely to be localized deposits along fault lines.

Groups of meteorite-producing meteoroids containing carbonaceous chondrite meteorites

NASA Astrophysics Data System (ADS)

Konovalova, N. A.; A.. Ibrohimov, A.; Kalashnikova, T. M.

2017-09-01

Proposed probable links of meteorite and meteorite-producing fireballs were been considered. Group associations between meteorite-producing meteoroids and meteorites were been determined for four carbonaceous chondrites Murchison, Maribo, Shutters Mill and Tagish Lake and potentially meteorite-producing bolides on the basis of links of their orbits. In result the several meteorite-producing sporadic slowly fireballs were found as the possible members of groups of four studied carbonaceous chondrite meteorites. One can presume that at present the identified groups may still contain large meteorite-dropping bodies.

How to Recognize and Avoid Potential, Possible, or Probable Predatory Open-Access Publishers, Standalone, and Hijacked Journals.

PubMed

Danevska, Lenche; Spiroski, Mirko; Donev, Doncho; Pop-Jordanova, Nada; Polenakovic, Momir

2016-11-01

The Internet has enabled an easy method to search through the vast majority of publications and has improved the impact of scholarly journals. However, it can also pose threats to the quality of published articles. New publishers and journals have emerged so-called open-access potential, possible, or probable predatory publishers and journals, and so-called hijacked journals. It was our aim to increase the awareness and warn scholars, especially young researchers, how to recognize these journals and how to avoid submission of their papers to these journals. Review and critical analysis of the relevant published literature, Internet sources and personal experience, thoughts, and observations of the authors. The web blog of Jeffrey Beall, University of Colorado, was greatly consulted. Jeffrey Beall is a Denver academic librarian who regularly maintains two lists: the first one, of potential, possible, or probable predatory publishers and the second one, of potential, possible, or probable predatory standalone journals. Aspects related to this topic presented by other authors have been discussed as well. Academics should bear in mind how to differentiate between trustworthy and reliable journals and predatory ones, considering: publication ethics, peer-review process, international academic standards, indexing and abstracting, preservation in digital repositories, metrics, sustainability, etc.

Lower survival probabilities for adult Florida manatees in years with intense coastal storms

USGS Publications Warehouse

Langtimm, C.A.; Beck, C.A.

2003-01-01

The endangered Florida manatee (Trichechus manatus latirostris) inhabits the subtropical waters of the southeastern United States, where hurricanes are a regular occurrence. Using mark-resighting statistical models, we analyzed 19 years of photo-identification data and detected significant annual variation in adult survival for a subpopulation in northwest Florida where human impact is low. That variation coincided with years when intense hurricanes (Category 3 or greater on the Saffir-Simpson Hurricane Scale) and a major winter storm occurred in the northern Gulf of Mexico. Mean survival probability during years with no or low intensity storms was 0.972 (approximate 95% confidence interval = 0.961-0.980) but dropped to 0.936 (0.864-0.971) in 1985 with Hurricanes Elena, Kate, and Juan; to 0.909 (0.837-0.951) in 1993 with the March "Storm of the Century"; and to 0.817 (0.735-0.878) in 1995 with Hurricanes Opal, Erin, and Allison. These drops in survival probability were not catastrophic in magnitude and were detected because of the use of state-of-the-art statistical techniques and the quality of the data. Because individuals of this small population range extensively along the north Gulf coast of Florida, it was possible to resolve storm effects on a regional scale rather than the site-specific local scale common to studies of more sedentary species. This is the first empirical evidence in support of storm effects on manatee survival and suggests a cause-effect relationship. The decreases in survival could be due to direct mortality, indirect mortality, and/or emigration from the region as a consequence of storms. Future impacts to the population by a single catastrophic hurricane, or series of smaller hurricanes, could increase the probability of extinction. With the advent in 1995 of a new 25- to 50-yr cycle of greater hurricane activity, and longer term change possible with global climate change, it becomes all the more important to reduce mortality and injury from boats and other human causes and control the loss of foraging habitat to coastal development.

Autonomous acoustic recorders reveal complex patterns in avian detection probability

USGS Publications Warehouse

Thompson, Sarah J.; Handel, Colleen M.; McNew, Lance B.

2017-01-01

Avian point‐count surveys are typically designed to occur during periods when birds are consistently active and singing, but seasonal and diurnal patterns of detection probability are often not well understood and may vary regionally or between years. We deployed autonomous acoustic recorders to assess how avian availability for detection (i.e., the probability that a bird signals its presence during a recording) varied during the breeding season with time of day, date, and weather‐related variables at multiple subarctic tundra sites in Alaska, USA, 2013–2014. A single observer processed 2,692 10‐minute recordings across 11 site‐years. We used time‐removal methods to assess availability and used generalized additive models to examine patterns of detectability (joint probability of presence, availability, and detection) for 16 common species. Despite lack of distinct dawn or dusk, most species displayed circadian vocalization patterns, with detection rates generally peaking between 0800 hours and 1200 hours but remaining high as late as 2000 hours for some species. Between 2200 hours and 0500 hours, most species’ detection rates dropped to near 0, signaling a distinctive rest period. Detectability dropped sharply for most species in early July. For all species considered, time‐removal analysis indicated nearly 100% likelihood of detection during a 10‐minute recording conducted in June, between 0500 hours and 2000 hours. This indicates that non‐detections during appropriate survey times and dates were attributable to the species’ absence or that silent birds were unlikely to initiate singing during a 10‐minute interval, whereas vocally active birds were singing very frequently. Systematic recordings revealed a gradient of species’ presence at each site, from ubiquitous to incidental. Although the total number of species detected at a site ranged from 16 to 27, we detected only 4 to 15 species on ≥5% of the site's recordings. Recordings provided an unusually detailed and consistent dataset that allowed us to identify, among other things, appropriate survey dates and times for species breeding at northern latitudes. Our results also indicated that more recordings of shorter duration (1–4 min) may be most efficient for detecting passerines.

CHEETAH: circuit-switched high-speed end-to-end transport architecture

NASA Astrophysics Data System (ADS)

Veeraraghavan, Malathi; Zheng, Xuan; Lee, Hyuk; Gardner, M.; Feng, Wuchun

2003-10-01

Leveraging the dominance of Ethernet in LANs and SONET/SDH in MANs and WANs, we propose a service called CHEETAH (Circuit-switched High-speed End-to-End Transport ArcHitecture). The service concept is to provide end hosts with high-speed, end-to-end circuit connectivity on a call-by-call shared basis, where a "circuit" consists of Ethernet segments at the ends that are mapped into Ethernet-over-SONET long-distance circuits. This paper focuses on the file-transfer application for such circuits. For this application, the CHEETAH service is proposed as an add-on to the primary Internet access service already in place for enterprise hosts. This allows an end host that is sending a file to first attempt setting up an end-to-end Ethernet/EoS circuit, and if rejected, fall back to the TCP/IP path. If the circuit setup is successful, the end host will enjoy a much shorter file-transfer delay than on the TCP/IP path. To determine the conditions under which an end host with access to the CHEETAH service should attempt circuit setup, we analyze mean file-transfer delays as a function of call blocking probability in the circuit-switched network, probability of packet loss in the IP network, round-trip times, link rates, and so on.

Dry friction avalanches: experiment and theory.

PubMed

Buldyrev, Sergey V; Ferrante, John; Zypman, Fredy R

2006-12-01

Experimental evidence and theoretical models are presented supporting the conjecture that dry friction stick-slip is described by self-organized criticality. We use the data, obtained with a pin-on-disk tribometer set to measure lateral force, to examine the variation of the friction force as a function of time. We study nominally flat surfaces of matching aluminum and steel. The probability distribution of force drops follows a negative power law with exponents mu in the range 3.2-3.5. The frequency power spectrum follows a 1/f alpha pattern with alpha in the range 1-1.8. We first compare these experimental results with the well-known Robin Hood model of self-organized criticality. We find good agreement between theory and experiment for the force-drop distribution but not for the power spectrum. We explain this on a physical basis and propose a model which takes explicitly into account the stiffness and inertia of the tribometer. Specifically, we numerically solve the equation of motion of a block on a friction surface pulled by a spring and show that for certain spring constants the motion is characterized by the same power law spectrum as in experiments. We propose a physical picture relating the fluctuations of the force drops to the microscopic geometry of the surface.

Optimizing Probability of Detection Point Estimate Demonstration

NASA Technical Reports Server (NTRS)

Koshti, Ajay M.

2017-01-01

Probability of detection (POD) analysis is used in assessing reliably detectable flaw size in nondestructive evaluation (NDE). MIL-HDBK-18231and associated mh18232POD software gives most common methods of POD analysis. Real flaws such as cracks and crack-like flaws are desired to be detected using these NDE methods. A reliably detectable crack size is required for safe life analysis of fracture critical parts. The paper provides discussion on optimizing probability of detection (POD) demonstration experiments using Point Estimate Method. POD Point estimate method is used by NASA for qualifying special NDE procedures. The point estimate method uses binomial distribution for probability density. Normally, a set of 29 flaws of same size within some tolerance are used in the demonstration. The optimization is performed to provide acceptable value for probability of passing demonstration (PPD) and achieving acceptable value for probability of false (POF) calls while keeping the flaw sizes in the set as small as possible.

Simulating the electrohydrodynamics of a viscous droplet

NASA Astrophysics Data System (ADS)

Theillard, Maxime; Saintillan, David

2016-11-01

We present a novel numerical approach for the simulation of viscous drop placed in an electric field in two and three spatial dimensions. Our method is constructed as a stable projection method on Quad/Octree grids. Using a modified pressure correction we were able to alleviate the standard time step restriction incurred by capillary forces. In weak electric fields, our results match remarkably well with the predictions from the Taylor-Melcher leaky dielectric model. In strong electric fields the so-called Quincke rotation is correctly reproduced.

Wotan’s Workshop: Military Experiments before World War II

DTIC Science & Technology

2013-06-27

photo: A column of mock tanks—with wood and canvas armor shapes mounted on light vehicles—participated in German military maneuvers in 1928. (Imperial...37mm antitank gun. The gunners called it a “ wood -o- meter” and claimed it could fire 400 splinters and 15 drops of turpentine per minute. Charles Gorry...ticipation in maneuvers. These surrogates, made of wood and canvas and mounted on cars or even on bicycles, were used in force-on-force maneuvers that

Hydroacoustic Propagation Through the Antarctic Convergence Zone: Study of Errors in Yield and Location Estimates for Explosive Charges

DTIC Science & Technology

2007-09-01

since water depth was only 800 m. Interestingly the signal from the 3rd drop has charge-seafloor range and bubble pulse frequency closer to what would...Hydrophone. A near-source hydrophone recording system was put together by Scripps Institution of Oceanography’s (SIO’s) Ocean Bottom Seismograph ...needed. We have thus proposed another research cruise to obtain more detailed measurements . Our new plan calls for several improvements to the previous

Far Forward Life Support System (FFLSS) Phase II

DTIC Science & Technology

2001-05-01

button will clear audible, flashing , or constant red alarms. Pushing the Config button drops down to the Level 2 menu (bottom line of Figure 8). In...disabled. Again, with testing this audible noise can be disabled. The visual flashing or constant red cannot be disabled. Pushing Return goes back to Level...Calling PLOTPIXEL( x ,y) and PLOTLINE(xl,x2,yl,y2) is as simple as pushing the appropriate bytes (unsigned integers) onto the stack and jumping to the

Truncated Long-Range Percolation on Oriented Graphs

NASA Astrophysics Data System (ADS)

van Enter, A. C. D.; de Lima, B. N. B.; Valesin, D.

2016-07-01

We consider different problems within the general theme of long-range percolation on oriented graphs. Our aim is to settle the so-called truncation question, described as follows. We are given probabilities that certain long-range oriented bonds are open; assuming that the sum of these probabilities is infinite, we ask if the probability of percolation is positive when we truncate the graph, disallowing bonds of range above a possibly large but finite threshold. We give some conditions in which the answer is affirmative. We also translate some of our results on oriented percolation to the context of a long-range contact process.

Determining animal drug combinations based on efficacy and safety.

PubMed

Kratzer, D D; Geng, S

1986-08-01

A procedure for deriving drug combinations for animal health is used to derive an optimal combination of 200 mg of novobiocin and 650,000 IU of penicillin for nonlactating cow mastitis treatment. The procedure starts with an estimated second order polynomial response surface equation. That surface is translated into a probability surface with contours called isoprobs. The isoprobs show drug amounts that have equal probability to produce maximal efficacy. Safety factors are incorporated into the probability surface via a noncentrality parameter that causes the isoprobs to expand as safety decreases, resulting in lower amounts of drug being used.

Optical burst switching for the next generation Optical Internet

NASA Astrophysics Data System (ADS)

Yoo, Myungsik

2000-11-01

In recent years, Internet Protocol (IP) over Wavelength Division Multiplexing (WDM) networks for the next generation Internet (or the so-called Optical Internet) have received enormous attention. There are two main drivers for an Optical Internet. One is the explosion of Internet traffic, which seems to keep growing exponentially. The other driver is the rapid advance in the WDM optical networking technology. In this study, key issues in the optical (WDM) layer will be investigated. As a novel switching paradigm for Optical Internet, Optical Burst Switching (OBS) is discussed. By leveraging the attractive properties of optical communications and at the same time, taking into account its limitations, OBS can combine the best of optical circuit-switching and packet/cell switching. The general concept of JET-based OBS protocol is described, including offset time and delayed reservation. In the next generation Optical Internet, one must address how to support Quality of Service (QoS) at the WDM layer since current IP provides only best effort services. The offset-time- based QoS scheme is proposed as a way of supporting QoS at the WDM layer. Unlike existing QoS schemes, offset- time-based QoS scheme does not mandate the use of buffer to differentiate services. For the bufferless WDM switch, the performance of offset- time-based QoS scheme is evaluated in term of blocking probability. In addition, the extra offset time required for class isolation is quantified and the theoretical bounds on blocking probability are analyzed. The offset-time-based scheme is applied to WDM switch with limited fiber delay line (FDL) buffer. We evaluate the effect of having a FDL buffer on the QoS performance of the offset-time-based scheme in terms of the loss probability and queuing delay of bursts. Finally, in order to dimension the network resources in Optical Internet backbone networks, the performance of the offset-time-based QoS scheme is evaluated for the multi-hop case. In particular, we consider very high performance Backbone Network Service (vBNS) backbone network. Various policies such as drop, retransmission, deflection routing and buffering are considered for performance evaluation. The performance results obtained under these policies are compared to decide the most efficient policy for the WDM backbone network.

Pupil dilation using a pledget sponge: a randomized controlled trial.

PubMed

McCormick, Austin; Srinivasan, Sathish; Harun, Shabbir; Watts, Mark

2006-08-01

To show that a pledget soaked in mydriatics and placed in the lower conjunctival fornix is as effective as drops in providing mydriasis for cataract surgery. A randomized, masked, controlled trial of 56 patients assigned to either a pledget group (n=25) or a control eye drops group (n=31) was carried out. Controls had the routine practice of repeated topical mydriatic drops: tropicamide, phenylepherine and atropine. The trial group had a 3-mm pledget trimmed, soaked in mydriatics and placed in the inferior fornix for 20 min. Pupil diameter was measured using a photographic technique with a standard scale shown in each picture. Two masked observers measured the pupils using the scale of the ruler in the developed photograph. All patients completed a 0-10 stinging score prior to surgery. There were no complications. The mean pupil diameter in the control group was 7.23 (6.91-7.94 95% confidence intervals [CI]) and 7.44 (6.96-7.92 95% CI) in the pledget group. There was no statistically significant difference in pupil diameter between the two groups: difference between means 0.21 (-0.32 to 0.75 95% CI) and Student's t-test of the difference between means (t=0.8 and two-tailed) probability P=0.43. There was no significant difference in the stinging scores: Mann-Whitney test P=0.69. The use of a pledget cellulose sponge to deliver mydriatics prior to cataract surgery is as effective as the conventional method of repeated drop administration and was not associated with any adverse effects.

Dynamic stress changes during earthquake rupture

USGS Publications Warehouse

Day, S.M.; Yu, G.; Wald, D.J.

1998-01-01

We assess two competing dynamic interpretations that have been proposed for the short slip durations characteristic of kinematic earthquake models derived by inversion of earthquake waveform and geodetic data. The first interpretation would require a fault constitutive relationship in which rapid dynamic restrengthening of the fault surface occurs after passage of the rupture front, a hypothesized mechanical behavior that has been referred to as "self-healing." The second interpretation would require sufficient spatial heterogeneity of stress drop to permit rapid equilibration of elastic stresses with the residual dynamic friction level, a condition we refer to as "geometrical constraint." These interpretations imply contrasting predictions for the time dependence of the fault-plane shear stresses. We compare these predictions with dynamic shear stress changes for the 1992 Landers (M 7.3), 1994 Northridge (M 6.7), and 1995 Kobe (M 6.9) earthquakes. Stress changes are computed from kinematic slip models of these earthquakes, using a finite-difference method. For each event, static stress drop is highly variable spatially, with high stress-drop patches embedded in a background of low, and largely negative, stress drop. The time histories of stress change show predominantly monotonic stress change after passage of the rupture front, settling to a residual level, without significant evidence for dynamic restrengthening. The stress change at the rupture front is usually gradual rather than abrupt, probably reflecting the limited resolution inherent in the underlying kinematic inversions. On the basis of this analysis, as well as recent similar results obtained independently for the Kobe and Morgan Hill earthquakes, we conclude that, at the present time, the self-healing hypothesis is unnecessary to explain earthquake kinematics.

The pressure field of imploding lightbulbs

NASA Astrophysics Data System (ADS)

Czechanowski, M.; Ikeda, C.; Duncan, J. H.

2015-03-01

The implosion of A19 incandescent lightbulbs in a high-pressure water environment is studied in a 1.77-m-diameter steel tank. Underwater blast sensors are used to measure the dynamic pressure field near the lightbulbs and the implosions are photographed with a high-speed movie camera at a frame rate of 24,000 pps. The movie camera and the pressure signal recording system are synchronized to enable correlation of features in the movie frames with those in the pressure records. It is found that the gross dimensions and weight of the bulbs are very similar from one bulb to another, but the ambient water pressure at which a given bulb implodes (, called the implosion pressure) varies from 6.29 to 11.98 atmospheres, probably due to inconsistencies in the glass wall thickness and perhaps other detailed characteristics of the bulbs. The dynamic pressures (the local pressure minus , as measured by the sensors) first drop during the implosion and then reach a strong positive peak at about the time that the bulb reaches minimum volume. The peak dynamic pressure varies from 3.61 to 28.66 atmospheres. In order to explore the physics of the implosion process, the dynamic pressure signals are compared to calculations of the pressure field generated by the collapse of a spherical bubble in a weakly compressible liquid. The wide range of implosion pressures is used in combination with the calculations to explore the effect of the relative liquid compressibility and the bulb itself on the dynamic pressure field.

Roles of Ethylene Production and Ethylene Receptor Expression in Regulating Apple Fruitlet Abscission1[OPEN

PubMed Central

Eccher, Giulia; Begheldo, Maura; Boschetti, Andrea; Ruperti, Benedetto; Botton, Alessandro

2015-01-01

Apple (Malus × domestica) is increasingly being considered an interesting model species for studying early fruit development, during which an extremely relevant phenomenon, fruitlet abscission, may occur as a response to both endogenous and/or exogenous cues. Several studies were carried out shedding light on the main physiological and molecular events leading to the selective release of lateral fruitlets within a corymb, either occurring naturally or as a result of a thinning treatment. Several studies pointed out a clear association between a rise of ethylene biosynthetic levels in the fruitlet and its tendency to abscise. A direct mechanistic link, however, has not yet been established between this gaseous hormone and the generation of the abscission signal within the fruit. In this work, the role of ethylene during the very early stages of abscission induction was investigated in fruitlet populations with different abscission potentials due either to the natural correlative inhibitions determining the so-called physiological fruit drop or to a well-tested thinning treatment performed with the cytokinin benzyladenine. A crucial role was ascribed to the ratio between the ethylene produced by the cortex and the expression of ethylene receptor genes in the seed. This ratio would determine the final probability to abscise. A working model has been proposed consistent with the differential distribution of four receptor transcripts within the seed, which resembles a spatially progressive cell-specific immune-like mechanism evolved by apple to protect the embryo from harmful ethylene. PMID:25888617

A systematic search of sudden pressure drops on Gale crater during two Martian years derived from MSL/REMS data

NASA Astrophysics Data System (ADS)

Ordonez-Etxeberria, Iñaki; Hueso, Ricardo; Sánchez-Lavega, Agustín

2018-01-01

The Mars Science Laboratory (MSL) rover carries a suite of meteorological detectors that constitute the Rover Environmental Monitoring Station (REMS) instrument. REMS investigates the meteorological conditions at Gale crater by obtaining high-frequency data of pressure, air and ground temperature, relative humidity, UV flux at the surface and wind intensity and direction with some limitations in the wind data. We have run a search of atmospheric pressure drops of short duration (< 25 s) and we present a statistical study of the frequency of these events in the REMS pressure data during its first 1417 sols (more than two Martian years). The identified daytime pressure drops could be caused by the close passages of warm vortices and dust devils. Previous systematic searches of warm vortices from REMS pressure data (Kahanpää et al., 2016; Steakley and Murphy, 2016) cover about one Martian year. We show that sudden pressure drops are twice more abundant in the second Martian year [sols 671-1339] than in the first one analyzed in previous works. The higher number of detections could be linked to a combination of different topography, higher altitudes (120 m above the landing site) and true inter-annual meteorological variability. We found 1129 events with a pressure drop larger than 0.5 Pa. Of these, 635 occurred during the local daytime (∼56%) and 494 were nocturnal. The most intense pressure drop (4.2 Pa) occurred at daytime on sol 1417 (areocentric solar longitude Ls = 195°) and was accompanied by a simultaneous decrease in the UV signal of 7.1%, pointing to a true dust devil. We also discuss similar but less intense simultaneous pressure and UV radiation drops that constitute 0.7% of all daytime events. Most of the intense daytime pressure drops with variations larger than 1.0 Pa occur when the difference between air and ground temperature is larger than 15 K. Statistically, the frequency of daytime pressure drops peaks close to noon (12:00-13:00 Local True Solar Time or LTST) with more events in spring and summer (Ls from 180° to 360°). The nocturnal sudden pressure drops concentrate in the 20:00-23:00 LTST time interval and they only occur in spring and summer. We interpret these nocturnal events as a consequence of local mechanically forced turbulence. This interpretation is consistent with published results from simulations with the MRAMS model (Rafkin et al., 2016) that predict a competition between local orographic circulation and global Hadley cell circulation at Gale crater at summer night-time that can enhance forced turbulence at the surface. Bursts of pressure drops appear on particular sols, especially at night-time. Most of the vortex bursts occurred when MSL was in the region called Pahrump Hills characterized by a complex terrain. A comparison of the daytime pressure drops from REMS data with published results from the Pathfinder and Phoenix missions shows that the frequency of daytime events at Gale crater in spring and summer is similar to the one previously found at other locations. Finally, we present possible correlations between MSL activity and some daytime pressure drops. If such an instrumental effect is present in the REMS data its impact in this analysis is small and would only affect about 7% of our detections.

Impact behavior of a high viscosity magnetorheological fluid-based energy absorber with a radial flow mode

NASA Astrophysics Data System (ADS)

Fu, Benyuan; Liao, Changrong; Li, Zhuqiang; Xie, Lei; Zhang, Peng; Jian, Xiaochun

2017-02-01

High viscosity linear polysiloxane magnetorheological fluid (HVLP MRF) was demonstrated with excellent suspension stability. Such material is suitable for application in the magnetorheological energy absorbers (MREAs) under axial impact loading conditions. On this basis, a new energy absorber incorporating a radial valve with high magnetic field utilization and a corrugated tube is proposed. In energy absorption applications where the MREA is rarely if ever used, our MREA takes the ultra-stable HVLP MRF as controlled medium in order for a long-term stability. For MREA performing at very high shear rates where the minor losses are important contributing factors to damping, a nonlinear analytical model, based on the Herschel-Bulkley flow model (HB model), is developed taking into account the effects of minor losses (called HBM model). The HB model parameters are determined by rheological experiments with a commercial shear rheometer. Then, continuity equation and governing differential equation of the HVLP MRF in radial flow are established. Based on the HB model, the expressions of radial velocity distribution are deduced. The influences of minor losses on pressure drop are analyzed with mean fluid velocities. Further, mechanical behavior of the corrugated tube is investigated via drop test. In order to verify the theoretical methodology, a MREA is fabricated and tested using a high-speed drop tower facility with a 600 kg mass at different drop heights and in various magnetic fields. The experiment results show that the HBM model is capable of well predicting the impact behavior of the proposed MREA.

Comparison between Pludix and impact/optical disdrometers during rainfall measurement campaigns

NASA Astrophysics Data System (ADS)

Caracciolo, Clelia; Prodi, Franco; Uijlenhoet, Remko

2006-11-01

The performances of two couples of disdrometers based on different measuring principles are compared: a classical Joss-Waldvogel disdrometer and a recently developed device, called the Pludix tested in Ferrara, Italy, and Pludix and the two-dimensional video disdrometer (2DVD) tested in Cabauw, The Netherlands. First, the measuring principles of the different instruments are presented and compared. Secondly, the performances of the two pairs of disdrometers are analysed by comparing their rain amounts with nearby tipping bucket rain gauges and the inferred drop size distributions. The most important rainfall integral parameters (e.g. rain rate and radar reflectivity) and drop size distribution parameters are also analysed and compared. The data set for Ferrara comprises 13 rainfall events, with a total of 20 mm of rainfall and a maximum rain rate of 4 mm h - 1 . The data set for Cabauw consists of 9 events, with 25-50 mm of rainfall and a maximum rain rate of 20-40 mm h - 1 . The Pludix tends to underestimate slightly the bulk rainfall variables in less intense events, whereas it tends to overestimate with respect to the other instruments in heavier events. The correspondence of the inferred drop size distributions with those measured by the other disdrometers is reasonable, particularly with the Joss-Waldvogel disdrometer. Considering that the Pludix is still in a calibration and testing phase, the reported results are encouraging. A new signal inversion algorithm, which will allow the detection of rain drops throughout the entire diameter interval between 0.3 and 7.0 mm, is under development.

Determination of Formulation Conditions Allowing Double Emulsions Stabilized by PGPR and Sodium Caseinate to Be Used as Capsules.

PubMed

Nollet, Maxime; Laurichesse, Eric; Besse, Samantha; Soubabère, Olivier; Schmitt, Véronique

2018-02-27

Water-in-oil-in-water (W 1 /O/W 2 ) double emulsions stabilized by polyglycerol polyricinoleate (PGPR), a lipophilic food grade small polymer, and sodium caseinate, a hydrophilic milk protein, were developed to encapsulate vitamin B12, a model hydrophilic substance easy to titrate. Using rheology, sensitive to drop size evolution and water fluxes, static light scattering, and microscopy both giving the evolution of drops' size and vitamin B12 titration assessing the encapsulation, we were able to detect independently the double emulsion drop size, the encapsulation loss, and the flux of water as a function of time. By differentiating the PGPR required to cover the W 1 -droplets' surface from PGPR in excess in the oil phase, we built a PGPR-inner droplet volume fraction diagram highlighting the domains where the double emulsion is stable toward encapsulation and/or water fluxes. We demonstrated the key role played by nonadsorbed PGPR concentration in the intermediate sunflower oil phase on the emulsion stability while, surprisingly, the inner droplet volume fraction had no effect on the emulsion stability. At low PGPR concentration, a release of vitamin B12 was observed and the leakage mechanism of coalescence between droplets and oil-water interface of the oily drops (also called globules hereafter), was identified using confocal microscopy. For high enough PGPR content, the emulsions were stable and may therefore serve as efficient capsules without need of an additional gelling, thickening, complexion or interface rigidifying agent. We generalized these results with the encapsulation of an insecticide: Cydia pomonella granulovirus used in organic arboriculture.

Implications of conflicting definitions of probability to health risk communication: a case study of familial cancer and genetic counselling.

PubMed

O'Doherty, Kieran C

2007-02-01

The question of what probability actually is has long been debated in philosophy and statistics. Although the concept of probability is fundamental to many applications in the health sciences, these debates are generally not well known to health professionals. This paper begins with an outline of some of the different interpretations of probability. Examples are provided of how each interpretation manifests in clinical practice. The discipline of genetic counselling (familial cancer) is used to ground the discussion. In the second part of the paper, some of the implications that different interpretations of probability may have in practice are examined. The main purpose of the paper is to draw attention to the fact that there is much contention as to the nature of the concept of probability. In practice, this creates the potential for ambiguity and confusion. This paper constitutes a call for deeper engagement with the ways in which probability and risk are understood in health research and practice.

HCl Vapour Pressures and Reaction Probabilities for ClONO2 + HCl on Liquid H2SO4-HNO3-HCl-H20 Solutions

NASA Technical Reports Server (NTRS)

Elrod, M. J.; Koch, R. E.; Kim, J. E.; Molina, M. J.

1995-01-01

Henry's Law solubility constants for HCl have been measured for liquid H2SO4-HNO3-HCl-H2O solutions; the results are in good agreement with predictions from published semiempirical models. The ClONO2 + HCl reaction on the surfaces of such solutions with compositions simulating those of stratospheric aerosols has been investigated; as the composition changes following the temperature drop characteristic of the high-latitude stratosphere the reaction probability gamma increases rapidly. Furthermore, the gamma values remain essentially unchanged when HN03 uptake is neglected; the controlling factor appears to be the solubility of HCl. These results corroborate our earlier suggestion that supercooled liquid sulfate aerosols promote chlorine activation at low temperatures as efficiently as solid polar stratospheric cloud particles.

Extended Eden model reproduces growth of an acellular slime mold.

PubMed

Wagner, G; Halvorsrud, R; Meakin, P

1999-11-01

A stochastic growth model was used to simulate the growth of the acellular slime mold Physarum polycephalum on substrates where the nutrients were confined in separate drops. Growth of Physarum on such substrates was previously studied experimentally and found to produce a range of different growth patterns [Phys. Rev. E 57, 941 (1998)]. The model represented the aging of cluster sites and differed from the original Eden model in that the occupation probability of perimeter sites depended on the time of occupation of adjacent cluster sites. This feature led to a bias in the selection of growth directions. A moderate degree of persistence was found to be crucial to reproduce the biological growth patterns under various conditions. Persistence in growth combined quick propagation in heterogeneous environments with a high probability of locating sources of nutrients.

Extended Eden model reproduces growth of an acellular slime mold

NASA Astrophysics Data System (ADS)

Wagner, Geri; Halvorsrud, Ragnhild; Meakin, Paul

1999-11-01

A stochastic growth model was used to simulate the growth of the acellular slime mold Physarum polycephalum on substrates where the nutrients were confined in separate drops. Growth of Physarum on such substrates was previously studied experimentally and found to produce a range of different growth patterns [Phys. Rev. E 57, 941 (1998)]. The model represented the aging of cluster sites and differed from the original Eden model in that the occupation probability of perimeter sites depended on the time of occupation of adjacent cluster sites. This feature led to a bias in the selection of growth directions. A moderate degree of persistence was found to be crucial to reproduce the biological growth patterns under various conditions. Persistence in growth combined quick propagation in heterogeneous environments with a high probability of locating sources of nutrients.

Impact of direct-to-consumer advertising for hereditary breast cancer testing on genetic services at a managed care organization: a naturally-occurring experiment.

PubMed

Mouchawar, Judy; Hensley-Alford, Sharon; Laurion, Suzanne; Ellis, Jennifer; Kulchak-Rahm, Alanna; Finucane, Melissa L; Meenan, Richard; Axell, Lisen; Pollack, Rebecca; Ritzwoller, Debra

2005-03-01

To describe the impact of Myriad Genetics, Inc.'s direct-to-consumer advertising (DTC-ad) campaign on cancer genetic services within two Managed Care Organizations, Kaiser Permanente Colorado (KPCO), Denver, Colorado, where the ad campaign occurred, and Henry Ford Health System (HFHS), Detroit, Michigan, where there were no advertisements. The main outcome measures were the changes in number and pretest mutation probability of referrals approved for cancer genetic services at KPCO and HFHS during the campaign versus the year prior, and mutation probability of those undergoing testing. At KPCO, referrals increased 244% during the DTC-ad compared to the same time period a year earlier (P value<0.001). The proportion of referrals at high pretest probability of a mutation (10% or greater) dropped from 69% the previous year to 48% during the campaign (P value<0.001). There was no significant change in pretest mutation probability among women who underwent testing between the two time periods. HFHS reported no significant change between the two time periods for numbers or mutation probability of referrals, or for mutation probability of women tested. The DTC-ad caused significant increase in demand for cancer genetic services. In the face of potential future DTC-ad for inherited cancer risk, providers and payers need to consider the delivery of genetic services and genetic education for persons of all risk levels.

Structuring as an Aid to Performance in Base-Rate Problems.

DTIC Science & Technology

1988-06-01

Design. All subjects were given two base-rate problems, here called the Lightbulb problem (adapted from Lyon & Slovic, 1976) and the Dyslexia problem; both...are shown in Table 1. Approximately half the subjects received the Lightbulb problem first; the others received the Dyslexia problem first. The two...probability that this bulb is really defective? [the child really has dyslexia ]? You can probably give a good estimate if you think hard and carefully

Constraints on scattering amplitudes in multistate Landau-Zener theory

NASA Astrophysics Data System (ADS)

Sinitsyn, Nikolai A.; Lin, Jeffmin; Chernyak, Vladimir Y.

2017-01-01

We derive a set of constraints, which we will call hierarchy constraints, on scattering amplitudes of an arbitrary multistate Landau-Zener model (MLZM). The presence of additional symmetries can transform such constraints into nontrivial relations between elements of the transition probability matrix. This observation can be used to derive complete solutions of some MLZMs or, for models that cannot be solved completely, to reduce the number of independent elements of the transition probability matrix.

Noncommutative Valuation of Options

NASA Astrophysics Data System (ADS)

Herscovich, Estanislao

2016-12-01

The aim of this note is to show that the classical results in finance theory for pricing of derivatives, given by making use of the replication principle, can be extended to the noncommutative world. We believe that this could be of interest in quantum probability. The main result called the First fundamental theorem of asset pricing, states that a noncommutative stock market admits no-arbitrage if and only if it admits a noncommutative equivalent martingale probability.

How Stitches Help Kids Heal

MedlinePlus

... cuts is a small sticky strip called a butterfly bandage. It keeps the edges of a shallow ... help. Different kinds of materials — sutures, glue, and butterflies — need different kinds of care. The doctor probably ...

Comparison of actual and seismologically inferred stress drops in dynamic models of microseismicity

NASA Astrophysics Data System (ADS)

Lin, Y. Y.; Lapusta, N.

2017-12-01

Estimating source parameters for small earthquakes is commonly based on either Brune or Madariaga source models. These models assume circular rupture that starts from the center of a fault and spreads axisymmetrically with a constant rupture speed. The resulting stress drops are moment-independent, with large scatter. However, more complex source behaviors are commonly discovered by finite-fault inversions for both large and small earthquakes, including directivity, heterogeneous slip, and non-circular shapes. Recent studies (Noda, Lapusta, and Kanamori, GJI, 2013; Kaneko and Shearer, GJI, 2014; JGR, 2015) have shown that slip heterogeneity and directivity can result in large discrepancies between the actual and estimated stress drops. We explore the relation between the actual and seismologically estimated stress drops for several types of numerically produced microearthquakes. For example, an asperity-type circular fault patch with increasing normal stress towards the middle of the patch, surrounded by a creeping region, is a potentially common microseismicity source. In such models, a number of events rupture the portion of the patch near its circumference, producing ring-like ruptures, before a patch-spanning event occurs. We calculate the far-field synthetic waveforms for our simulated sources and estimate their spectral properties. The distribution of corner frequencies over the focal sphere is markedly different for the ring-like sources compared to the Madariaga model. Furthermore, most waveforms for the ring-like sources are better fitted by a high-frequency fall-off rate different from the commonly assumed value of 2 (from the so-called omega-squared model), with the average value over the focal sphere being 1.5. The application of Brune- or Madariaga-type analysis to these sources results in the stress drops estimates different from the actual stress drops by a factor of up to 125 in the models we considered. We will report on our current studies of other types of seismic sources, such as repeating earthquakes and foreshock-like events, and whether the potentially realistic and common sources different from the standard Brune and Madariaga models can be identified from their focal spectral signatures and studied using a more tailored seismological analysis.

Option volatility and the acceleration Lagrangian

NASA Astrophysics Data System (ADS)

Baaquie, Belal E.; Cao, Yang

2014-01-01

This paper develops a volatility formula for option on an asset from an acceleration Lagrangian model and the formula is calibrated with market data. The Black-Scholes model is a simpler case that has a velocity dependent Lagrangian. The acceleration Lagrangian is defined, and the classical solution of the system in Euclidean time is solved by choosing proper boundary conditions. The conditional probability distribution of final position given the initial position is obtained from the transition amplitude. The volatility is the standard deviation of the conditional probability distribution. Using the conditional probability and the path integral method, the martingale condition is applied, and one of the parameters in the Lagrangian is fixed. The call option price is obtained using the conditional probability and the path integral method.

The lattice of trumping majorization for 4D probability vectors and 2D catalysts.

PubMed

Bosyk, Gustavo M; Freytes, Hector; Bellomo, Guido; Sergioli, Giuseppe

2018-02-27

The transformation of an initial bipartite pure state into a target one by means of local operations and classical communication and entangled-assisted by a catalyst defines a partial order between probability vectors. This partial order, so-called trumping majorization, is based on tensor products and the majorization relation. Here, we aim to study order properties of trumping majorization. We show that the trumping majorization partial order is indeed a lattice for four dimensional probability vectors and two dimensional catalysts. In addition, we show that the subadditivity and supermodularity of the Shannon entropy on the majorization lattice are inherited by the trumping majorization lattice. Finally, we provide a suitable definition of distance for four dimensional probability vectors.

Predicting relative sea level changes at the aftermath of Marinoan (635 Ma) Snowball meltdown

NASA Astrophysics Data System (ADS)

Irie, Y.; Nakada, M.; Okuno, J.; Bao, H.

2016-12-01

Earth system recovery from a Snowball state constitutes one of the best tests of the resilience of life on planet Earth. A distinct and probably brief relative sea level (RSL) drop has been identified in the cap dolostones deposited in a general transgression sequence at the aftermath of Marinoan Snowball meltdown in South China and other late Neoproterozoic blocks. However, the magnitude and duration or the very existence of this RSL drop event can vary at different geographical sites because of spatial and temporal variations in sea level due to glacial isostatic adjustment (GIA) even for tectonically stable areas. An accurate prediction of this drop can in turn help us infer independently the rate of dynamic recovery of the Earth system from a Snowball state, e.g. the timing and duration of the Marinoan 17O depletion (MOSD) event that was also closely linked to the rise and drawdown of atmospheric O2 and CO2, respectively. Here we model the RSL changes by considering all GIA-related relaxation processes. We evaluated the RSL to the sea level at 10 Myr after the complete glacial meltdown and tested slightly different paleogeographic configurations. Our modeling results show that the RSL drop occurs in the syn-deglacial phase (melting phase) for the inland regions and in the post-deglacial phase (time after the complete melting) for continental margins. The RSL drop in the post-deglacial phase is mainly determined by the relaxation processes with a timescale of longer than 20 kyr. The predicted RSL change in South China for lower mantle viscosity of 1022-1023 Pa s and a syn-deglacial time of <100 kyr is consistent with the observationally inferred RSL change regardless of uncertainties on the length of the continental shelf or the paleogeography of South China. A comparison between our model predicted and sedimentary-record inferred RSL change in South China put an independent constraint on the duration of the MOSD event at 70 kyr or shorter.

Evaluation of the status of anurans on a refuge in suburban Maryland

USGS Publications Warehouse

Brander, S.M.; Royle, J. Andrew; Eames, M.

2007-01-01

Because many anurans have well-defined breeding seasons and male anurans produce loud advertisement calls, surveys of these breeding choruses are believed to provide a dependable means of monitoring population trends. The Patuxent Research Refuge initiated such a calling survey in the spring of 1997, which uses volunteers to collect anuran (frog and toad) calling survey data. The primary goal of initiating the calling surveys at the Patuxent Refuge was to obtain baseline information on anuran populations, such as species occurrence, frequency of occurrence, and relative abundance over time. In this paper, we used the calling survey data to develop models for the ?proportion of area occupied? by individual anuran species, a method in which analysis is focused on the proportion of sites that are occupied by a species, instead of the number of individuals present in the population. This type of analysis is ideal for use in large-scale monitoring programs focused on species that are difficult to count, such as anurans or birds. We considered models for proportion of area occupied that allow for imperfect detection (that is, a species may be present but go undetected during sampling) by incorporating parameters that describe detection probability and the response of detection probability to various environmental and sampling covariates. Our results indicate that anuran populations on the Patuxent Research Refuge have high rates of occupancy compared to areas nearby and that extinction and colonization rates are stable. The potential uses for ?proportion of area occupied? analyses are far-reaching and will allow for more accurate quantification of data and better-informed management decisions for calling surveys on a larger scale.

Evaluation of the status of anurans on a refuge in suburban Maryland

USGS Publications Warehouse

Brander, S.M.; Royle, J. Andrew; Eames, M.

2007-01-01

Because many anurans have well-defined breeding seasons and male anurans produce loud advertisement calls, surveys of these breeding choruses are believed to provide a dependable means of monitoring population trends. The Patuxent Research Refuge initiated such a calling survey in the spring of 1997, which uses volunteers to collect anuran (frog and toad) calling survey data. The primary goal of initiating the calling surveys at the Patuxent Refuge was to obtain baseline information on anuran populations, such as species occurrence, frequency of occurrence, and relative abundance over time. In this paper, we used the calling survey data to develop models for the "proportion of area occupied" by individual anuran species, a method in which analysis is focused on the proportion of sites that are occupied by a species, instead of the number of individuals present in the population. This type of analysis is ideal for use in large-scale monitoring programs focused on species that are difficult to count, such as anurans or birds. We considered models for proportion of area occupied that allow for imperfect detection (that is, a species may be present but go undetected during sampling) by incorporating parameters that describe detection probability and the response of detection probability to various environmental and sampling covariates. Our results indicate that anuran populations on the Patuxent Research Refuge have high rates of occupancy compared to areas nearby and that extinction and colonization rates are stable. The potential uses for "proportion of area occupied" analyses are far-reaching and will allow for more accurate quantification of data and better-informed management decisions for calling surveys on a larger scale. Copyright 2007 Society for the Study of Amphibians and Reptiles.

The trading time risks of stock investment in stock price drop

NASA Astrophysics Data System (ADS)

Li, Jiang-Cheng; Tang, Nian-Sheng; Mei, Dong-Cheng; Li, Yun-Xian; Zhang, Wan

2016-11-01

This article investigates the trading time risk (TTR) of stock investment in the case of stock price drop of Dow Jones Industrial Average (ˆDJI) and Hushen300 data (CSI300), respectively. The escape time of stock price from the maximum to minimum in a data window length (DWL) is employed to measure the absolute TTR, the ratio of the escape time to data window length is defined as the relative TTR. Empirical probability density functions of the absolute and relative TTRs for the ˆDJI and CSI300 data evidence that (i) whenever the DWL increases, the absolute TTR increases, the relative TTR decreases otherwise; (ii) there is the monotonicity (or non-monotonicity) for the stability of the absolute (or relative) TTR; (iii) there is a peak distribution for shorter trading days and a two-peak distribution for longer trading days for the PDF of ratio; (iv) the trading days play an opposite role on the absolute (or relative) TTR and its stability between ˆDJI and CSI300 data.

Reliable WDM multicast in optical burst-switched networks

NASA Astrophysics Data System (ADS)

Jeong, Myoungki; Qiao, Chunming; Xiong, Yijun

2000-09-01

IN this paper,l we present a reliable WDM (Wavelength-Division Multiplexing) multicast protocol in optical burst-switched (OBS) networks. Since the burst dropping (loss) probability may be potentially high in a heavily loaded OBS backbone network, reliable multicast protocols that have developed for IP networks at the transport (or application) layer may incur heavy overheads such as a large number of duplicate retransmissions. In addition, it may take a longer time for an end host to detect and then recover from burst dropping (loss) occurred at the WDM layer. For efficiency reasons, we propose burst loss recovery within the OBS backbone (i.e., at the WDM link layer). The proposed protocol requires two additional functions to be performed by the WDM switch controller: subcasting and maintaining burst states, when the WDM switch has more than one downstream on the WDM multicast tree. We show that these additional functions are simple to implement and the overhead associated with them is manageable.

Electrochemical behavior of phytochelatins and related peptides at the hanging mercury drop electrode in the presence of cobalt(II) ions.

PubMed

Dorcák, Vlastimil; Sestáková, Ivana

2006-01-01

Direct current voltammetry and differential pulse voltammetry have been used to investigate the electrochemical behaviour of two phytochelatins: heptapeptide (gamma-Glu-Cys)3-Gly and pentapeptide (gamma-Glu-Cys)2-Gly, tripeptide glutathione gamma-Glu-Cys-Gly and its fragments: dipeptides Cys-Gly and gamma-Glu-Cys at the hanging mercury drop electrode in the presence of cobalt(II) ions. Most interesting results were obtained with direct current voltammetry in the potential region of -0.80 V up to -1.80 V. Differential pulse voltammetry of the same solutions of Co(II) with peptides gives more complicated voltammograms with overlapping peaks, probably in connection with the influence of adsorption at slow scan rates necessarily used in this method. However, in using Brdicka catalytic currents for analytical purposes, differential pulse voltammograms seem to be more helpful. Presented investigations have shown that particularly the prewave of cobalt(II) allows distinguishing among phytochelatins, glutathione, and its fragments.

Evaluation of a locally homogeneous model of spray evaporation

NASA Technical Reports Server (NTRS)

Shearer, A. J.; Faeth, G. M.; Tamura, H.

1978-01-01

Measurements were conducted on an evaporating spray in a stagnant environment. The spray was formed using an air-atomizing injector to yield a Sauter mean diameter of the order of 30 microns. The region where evaporation occurred extended approximately 1 m from the injector for the test conditions. Profiles of mean velocity, temperature, composition, and drop size distribution, as well as velocity fluctuations and Reynolds stress, were measured. The results are compared with a locally homogeneous two-phase flow model which implies no velocity difference and thermodynamic equilibrium between the phases. The flow was represented by a k-epsilon-g turbulence model employing a clipped Gaussian probability density function for mixture fraction fluctuations. The model provides a good representation of earlier single-phase jet measurements, but generally overestimates the rate of development of the spray. Using the model predictions to represent conditions along the centerline of the spray, drop life-history calculations were conducted which indicate that these discrepancies are due to slip and loss of thermodynamic equilibrium between the phases.

Weight loss and isotopic shifts for water drops frozen on a liquid nitrogen surface.

PubMed

Eguchi, Keiko; Abe, Osamu; Hiyama, Tetsuya

2008-10-01

A liquid nitrogen freezing method was used to collect raindrops for the determination of isotope-size distribution. Water drops that fall onto a surface of liquid nitrogen stay suspended for 10 to 20 s, until their temperature reaches the Leidenfrost point (126 K). As their temperature falls to the freezing point, they release their heat by thermal conduction. At the freezing point, latent heat of fusion is released, along with a significant loss of water. After freezing completely, the ice droplets stay suspended, cooling by thermal conduction until they reach the Leidenfrost point. They then lose buoyancy and start sinking. Consistent isotopic changes of 1.5 +/- 0.4 and 0.33 +/- 0.05 per thousand for hydrogen and oxygen, respectively, were found for droplets with radii between 1.0 and 1.5 mm. Isotope fractionation appeared to occur at the same time as water loss, as the droplets were freezing, in what was probably a kinetic effect.

[The comparison on growth rate and photopigments of filaments of Spirulina platensis strain Z with different morphology].

PubMed

Wang, Z; Cui, H; Zhu, J; Jia, X; Qian, K

1998-08-01

The line-shaped filaments Sp-Z(L) were isolated and cultured from Spirulina platensis Sp-Z. The growth rate of Sp-Z(L) was only 64% as much as that of Sp-Z when the light intensity was 4000 Lux. The contents (x 10(-3) g/g dry weight) of chlorophylls, carotenoids and phycobilins of Sp-Z(L) and Sp-Z were 20.6, 0.343, 5.00 and 24.1 0.297, 4.46, respectively. Moreover, as to the absorption spectra of the three photopigments of Sp-Z(L), red shifts were observed. Therefore, after the spiral Sp-Z breeded or changed into Sp-Z(L), The contents of carotenoids and phycobilins raised 23% and 12%, respectively, but the contents of chlorophylls dropped 14.5%, and the growth rate dropped 36% too. The results probably showed that the decrease of chlorophylls was one of the main reasons that caused the remarkable decrease of the growth rate of Sp-Z(L).

Modeling of Yb3+/Er3+-codoped microring resonators

NASA Astrophysics Data System (ADS)

Vallés, Juan A.; Gălătuş, Ramona

2015-03-01

The performance of a highly Yb3+/Er3+-codoped phosphate glass add-drop microring resonator is numerically analyzed. The model assumes resonant behaviour of both pump and signal powers and the dependences of pump intensity build-up inside the microring resonator and of the signal transfer functions to the device through and drop ports are evaluated. Detailed equations for the evolution of the rare-earth ions levels population densities and the propagation of the optical powers inside the microring resonator are included in the model. Moreover, due to the high dopant concentrations considered, the microscopic statistical formalism based on the statistical average of the excitation probability of the Er3+ ion in a microscopic level has been used to describe energy-transfer inter-atomic mechanisms. Realistic parameters and working conditions are used for the calculations. Requirements to achieve amplification and laser oscillation within these devices are obtainable as a function of rare earth ions concentration and coupling losses.

An Experimental Investigation of Fluid Flow Resulting from the Impact of a Water Drop with an Unyielding Dry Surface

NASA Astrophysics Data System (ADS)

Stow, C. D.; Hadfield, M. G.

1981-01-01

The flow of fluid associated with the impact of water drops of radius R at a speed V onto unyielding dry metal surfaces of known roughness R_a is described. Spatial dimensions of the deforming drop are normalized by transformations of the kind x' = x/R, and time scales are normalized according to t' = tV/R, to permit comparison of events where R or V differ. It is shown that the primary influence of the surface roughness parameter R_a is the determination of the condition for the ejection of secondary droplets by the excitation of an instability in the developing watersheet; provided R_a ~= R, it is possible to evaluate the condition to a high degree of accuracy, and for R_a = 0.84 μ m it is found to be α4/3RV1.69 > 7.4, where α is the eccentricity of the drop at the moment of impact. Deceleration of the drop apex does not commence until t' > 0.6, contrary to the prediction of Engel (1955) but in good agreement with that of Savic & Boult (1957). Close examination of the very early stages of impact suggests strongly that the so-called watersheet originates at a moment t' = 0.01 after first contact, regardless of the absolute values of R, V or R_a; the initial normalized watersheet velocity is of order 5. Where there is ejected material, its normalized velocity at the moment of ejection is of the order of 20% greater than that of the watersheet substrate. Simple calculations also suggest that initial fluid velocities greater than 10V are required immediately before the initiation of the watersheet (t' < 0.01). Impacts at speeds considerably greater than the appropriate terminal fall speed in air show no deviations in character from those investigated at much lower speeds. A simple subsidiary experiment also suggests that greater impact velocities are required to produce splashing on inclined targets.

Using an emergency response infrastructure to help women who experience gender-based violence in Gujarat, India.

PubMed

Newberry, Jennifer A; Mahadevan, Swaminatha; Gohil, Narendrasinh; Jamshed, Roma; Prajapati, Jashvant; Rao, Gv Ramana; Strehlow, Matthew

2016-05-01

Many women who experience gender-based violence may never seek any formal help because they do not feel safe or confident that they will receive help if they try. A public-private-academic partnership in Gujarat, India, established a toll-free telephone helpline - called 181 Abhayam - for women experiencing gender-based violence. The partnership used existing emergency response service infrastructure to link women to phone counselling, nongovernmental organizations (NGOs) and government programmes. In India, the lifetime prevalence of gender-based violence is 37.2%, but less than 1% of women will ever seek help beyond their family or friends. Before implementation of the helpline, there were no toll-free helplines or centralized coordinating systems for government programmes, NGOs and emergency response services. In February 2014, the helpline was launched across Gujarat. In the first 10 months, the helpline assisted 9767 individuals, of which 8654 identified themselves as women. Of all calls, 79% (7694) required an intervention by phone or in person on the day they called and 43% (4190) of calls were by or for women experiencing violence. Despite previous data that showed women experiencing gender-based violence rarely sought help from formal sources, women in Gujarat did use the helpline for concerns across the spectrum of gender-based violence. However, for evaluating the impact of the helpline, the operational definitions of concern categories need to be further clarified. The initial triage system for incoming calls was advantageous for handling high call volumes, but may have contributed to dropped calls.

Vocalisations and acoustic parameters of flock noise from feather pecking and non-feather pecking laying flocks.

PubMed

Bright, A

2008-05-01

1. In this study, the calling rates of vocalisations known to indicate distress and aversive events (Alarm calls, Squawks, Total vocalisations) and acoustic parameters of flock noise were quantified from feather and non-feather pecking laying flocks. 2. One hour of flock noise (background machinery and hen vocalisations) was recorded from 21 commercial free-range laying hen flocks aged > or =35 weeks. Ten of the flocks were classified as feather pecking (based on a plumage condition score) and 11 as non-feather pecking. 3. Recordings were made using a Sony DAT recorder and Audio-Technica omni-directional microphone, placed in the centre of the house-1.5 m from the ground. Avisoft-SASlab Pro was used to create and analyse audio spectrograms. 4. There was no effect of flock size or farm on call/s or acoustic parameters of flock noise. However, strain had an effect on the number of Total vocalisation/s; the Hebden Black flock made more calls than Lohmann flocks. Feather pecking flocks gave more Squawk/s and more Total vocalisation/s than non-feather pecking flocks. Feather pecking did not explain variation in alarm call rate or, intensity (dB) and frequency (Hz) measures of flock noise. 5. The differences between Squawk and Total vocalisation call rates of feather and non-feather pecking flocks are a new finding. An increase or change in flock calling rate may be evident before other conventional measures of laying hen welfare such as a drop in egg production or increase in plumage damage, thus enabling farmers to make management or husbandry changes to prevent an outbreak of feather pecking.

Constraints on scattering amplitudes in multistate Landau-Zener theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinitsyn, Nikolai A.; Lin, Jeffmin; Chernyak, Vladimir Y.

2017-01-30

Here, we derive a set of constraints, which we will call hierarchy constraints, on scattering amplitudes of an arbitrary multistate Landau-Zener model (MLZM). The presence of additional symmetries can transform such constraints into nontrivial relations between elements of the transition probability matrix. This observation can be used to derive complete solutions of some MLZMs or, for models that cannot be solved completely, to reduce the number of independent elements of the transition probability matrix.

User’s guide for MapMark4—An R package for the probability calculations in three-part mineral resource assessments

USGS Publications Warehouse

Ellefsen, Karl J.

2017-06-27

MapMark4 is a software package that implements the probability calculations in three-part mineral resource assessments. Functions within the software package are written in the R statistical programming language. These functions, their documentation, and a copy of this user’s guide are bundled together in R’s unit of shareable code, which is called a “package.” This user’s guide includes step-by-step instructions showing how the functions are used to carry out the probability calculations. The calculations are demonstrated using test data, which are included in the package.

Do we have what it takes to put all students on the graduation path?

PubMed

Legters, Nettie; Balfanz, Robert

2010-01-01

According to current estimates, more than a quarter of all students and over 40 percent of African American and Hispanic students do not graduate from high school on time. The vast majority of those young people who do not graduate with their peers drop out. The enormous costs to these individuals, their communities, and our society require us to invest in systems that accurately identify young people at risk of dropping out and provide the supports necessary to keep them on track to graduation. This chapter offers a framework for action that calls on communities to identify the scale and scope of the dropout problem and understand why students disengage from school; transform or replace low-performing schools; install early warning and multitiered response systems that provide comprehensive, targeted, and intensive supports to students in and out of school; establish supportive policies and resource allocations; and build community will and capacity so positive changes are deeply implemented and sustained.

Modeling of Turbulence Effects on Liquid Jet Atomization and Breakup

NASA Technical Reports Server (NTRS)

Trinh, Huu P.; Chen, C. P.

2005-01-01

Recent experimental investigations and physical modeling studies have indicated that turbulence behaviors within a liquid jet have considerable effects on the atomization process. This study aims to model the turbulence effect in the atomization process of a cylindrical liquid jet. Two widely used models, the Kelvin-Helmholtz (KH) instability of Reitz (blob model) and the Taylor-Analogy-Breakup (TAB) secondary droplet breakup by O Rourke et al, are further extended to include turbulence effects. In the primary breakup model, the level of the turbulence effect on the liquid breakup depends on the characteristic scales and the initial flow conditions. For the secondary breakup, an additional turbulence force acted on parent drops is modeled and integrated into the TAB governing equation. The drop size formed from this breakup regime is estimated based on the energy balance before and after the breakup occurrence. This paper describes theoretical development of the current models, called "T-blob" and "T-TAB", for primary and secondary breakup respectivety. Several assessment studies are also presented in this paper.

Suppressing the coffee stain effect: how to control colloidal self-assembly in evaporating drops using electrowetting

NASA Astrophysics Data System (ADS)

Eral, Burak; Mampallil Augustine, Dileep; Duits, Michel; Mugele, Frieder; Physics of Complex Fluids Group, University of Twente Team

2011-11-01

We study the influence of electrowetting on the evaporative self-assembly and formation of undesired solute residues, so-called coffee stains, during the evaporation of a drop containing non-volatile solvents. Electrowetting is found to suppress coffee stains of both colloidal particles of various sizes and DNA solutions at alternating (AC) frequencies ranging from a few Hertz to a few tens of kHz. Two main effects are shown to contribute to the suppression: (i) the time-dependent electrostatic force prevents pinning of the three phase contact line and (ii) internal flow fields generated by AC electrowetting counteract the evaporation driven flux and thereby prevent the accumulation of solutes along the contact line Please see the link below for a short presentation and movies: http://www.youtube.com/watch?v=xwipCVZnN4E We thank the Chemical Sciences division of the Netherlands Organization for Scientific Research (NWO-CW) for financial support (ECHO grant).

A Study of Eutectic Gallium Indium Liquid Metal in Microsystems and Interfaces

NASA Astrophysics Data System (ADS)

Mohammed, Mohammed Gamal Abdel Naser

This dissertation studies the behavior of the eutectic alloy of gallium and indium (commonly called EGaIn) in microfluidic channels, on thin metal films and with metal powders. EGaIn is a metal alloy that is liquid at room temperature, has high surface tension and low viscosity. EGaIn forms in presence of oxygen a thin robust oxide skin that allows the liquid metal to take non-spherical shapes despite its high surface tension. The first chapter discusses properties and applications of liquid metals in general and EGaIn in more details. The second chapter studies the phenomenon of spectral colors that appear on PDMS microchannels filled with EGaIn upon applying a compression strain on it. The channels are sealed using oxygen plasma which alters the surface chemistry by attaching oxygen atoms to it and forming a thin rigid film. Buckles form on that thin rigid layer when the channel is compressed due to the difference in elastic moduli between the film and the bulk of PDMS. Optical microscopy and AFM confirmed the presence of the buckles. The third chapter presents a new method for producing liquid metal droplets by forcing EGaIn into reservoirs with designed dimensions. The dimensions of the reservoir can be easily manipulated to produce the desired drop size. We can collect the drops or embed them in PDMS. The fourth chapter studies the behavior of these drops upon contacting metal films. EGaIn drops self-run on weakly-bounded metal films to substrate in media that continuously etch its oxide skin like acid solution or under reducing bias. Our experiments show that EGaIn drops achieve the highest velocities on films of Ag over Au on glass substrates. The running mechanism is novel and has not been reported before, the liquid metal drop pulls the film from the substrate while dissolving it and running forward. The contact between the EGaIn drop and the metal film creates an electrochemical cell that leads to formation of hydrogen bubbles beneath the metal film, the bubbles make the film loose and easy for the EGaIn drop to pull. We investigated the role of drop diameter to film width ratio and the degree of saturation with the other metal on the speed of the drop. The velocity we report is higher than that of any self-running liquid metal drop and any aqueous creature. Self-running drops have potential applications such as fabricating self-destroying electronic circuits. The fifth chapter explores a new method to create metal micro and nanostructures at ambient conditions by imprinting a paste made by mixing gallium and metal powders against molds. Gallium and metal powder interdiffuse in a short period of time and form a solid alloy. In this study we use copper powder as it is not expensive, safe to work with and can form a solid alloy with gallium at room temperature. We investigated the optimum mixing ratio (65 wt% Ga and 35 wt% Cu) that allows easy mixing, enough workable time and results in a solid alloy as diffusion proceeds. The paste can replicate relatively big features (features on a penny for instance) and create free standing structures, however imprints of small features suffers from imperfections. Milling and reducing the powder under inert atmosphere helped to enhance mixing. We are currently studying the effect of particle size on replication and homogeneity of the solid alloy.

Test Methodologies for Personal Protective Equipment Against Anti-Personnel Mine Blast (Methodologies d’essais pour le materiel de protection prsonnel contre le souffle produit par les mines antipersonnel)

DTIC Science & Technology

2004-03-01

probabilistic by design. Finally, as the fragments disperse, fragment density decreases, and the probability of a fragment strike drops rapidly. Given the...Any PPE subjected to such testing needs to be exposed repeatedly to several mines in order to obtain a sufficient number of strikes . This will allow...velocity of each fragment, and the location of fragment strikes cannot be controlled precisely. This means that the same test must be repeated a

System implications of the ambulance arrival-to-patient contact interval on response interval compliance.

PubMed

Campbell, J P; Gratton, M C; Salomone, J A; Lindholm, D J; Watson, W A

1994-01-01

In some emergency medical services (EMS) system designs, response time intervals are mandated with monetary penalties for noncompliance. These times are set with the goal of providing rapid, definitive patient care. The time interval of vehicle at scene-to-patient access (VSPA) has been measured, but its effect on response time interval compliance has not been determined. To determine the effect of the VSPA interval on the mandated code 1 (< 9 min) and code 2 (< 13 min) response time interval compliance in an urban, public-utility model system. A prospective, observational study used independent third-party riders to collect the VSPA interval for emergency life-threatening (code 1) and emergency nonlife-threatening (code 2) calls. The VSPA interval was added to the 9-1-1 call-to-dispatch and vehicle dispatch-to-scene intervals to determine the total time interval from call received until paramedic access to the patient (9-1-1 call-to-patient access). Compliance with the mandated response time intervals was determined using the traditional time intervals (9-1-1 call-to-scene) plus the VSPA time intervals (9-1-1 call-to-patient access). Chi-square was used to determine statistical significance. Of the 216 observed calls, 198 were matched to the traditional time intervals. Sixty-three were code 1, and 135 were code 2. Of the code 1 calls, 90.5% were compliant using 9-1-1 call-to-scene intervals dropping to 63.5% using 9-1-1 call-to-patient access intervals (p < 0.0005). Of the code 2 calls, 94.1% were compliant using 9-1-1 call-to-scene intervals. Compliance decreased to 83.7% using 9-1-1 call-to-patient access intervals (p = 0.012). The addition of the VSPA interval to the traditional time intervals impacts system response time compliance. Using 9-1-1 call-to-scene compliance as a basis for measuring system performance underestimates the time for the delivery of definitive care. This must be considered when response time interval compliances are defined.

Two Further Experiments on Electron Interference

ERIC Educational Resources Information Center

Matteucci, G.; Pozzi, G.

1978-01-01

Presents the results of two experiments concerning the phenomena of the interference of probabilities and of the so called Aharonov-Bohm effect. An electron biprism and a standard electron microscope have been used for the experiments. (Author/GA)

Nile damming as plausible cause of extinction and drop in abundance of deep-sea shrimp in the western Mediterranean over broad spatial scales

NASA Astrophysics Data System (ADS)

Cartes, J. E.; Maynou, F.; Fanelli, E.

2011-11-01

Greatly increased retention of flow in Nile River reservoirs was initiated in 1964, after completion of the Aswan High Dam, which induced important oceanographic changes in the Mediterranean Sea, including deep waters (below a depth of 150 m). Based on an analysis of data series starting in the 1940s/1950s, the giant red shrimp Aristaeomorpha foliacea has become locally extinct off of the Catalonian coasts (and elsewhere in the northwestern Mediterranean) at depths of 400-900 m, with a simultaneous and significant drop in the catches of red shrimp, Aristeus antennatus, in the second half of the 1960s. The extinction and sharp decline of deep-shrimp populations off Catalonian coast (at ca. 3200 km westwards from Nile Delta) followed the 1964 drop in Nile discharge with a delay of ca. 3-5 yrs (breakpoint analysis applied to data series). The breakpoints detected in the second half of 1960s both in Nile runoff and shrimps’ abundance were independent of climatic events in the study area (e.g. changes in NAO) and occurred before the increase in fishing effort off Catalonian coasts (breakpoint in 1973-1974). The Levantine Intermediate Water (LIW), inhabited by A. foliacea in the western Basin, had significant temperature (T) and salinity (S) increases in the 1950-1970 period, and Nile damming has contributed about 45% of the total S increase of Western Mediterranean deep-water masses from the 1960s to the late 1990s (Skliris and Lascaratos, 2004). This had to increase, for instance, LIW salinity at its formation site in the eastern Mediterranean. Nile damming was probably a triggering factor for the extinction/drop in abundance of deep-sea shrimp off Catalonian coasts.

Black holes in short period X-ray binaries and the transition to radiatively inefficient accretion

NASA Astrophysics Data System (ADS)

Knevitt, G.; Wynn, G. A.; Vaughan, S.; Watson, M. G.

2014-02-01

By comparing the orbital period distributions of black hole and neutron star low-mass X-ray binaries (LMXBs) in the Ritter-Kolb catalogue we show that there is statistical evidence for a dearth of black hole systems at short orbital periods (Porb < 4 h). This could either be due to a true divergence in orbital period distributions of these two types of system, or to black hole LMXBs being preferentially hidden from view at short orbital periods. We explore the latter possibility, by investigating whether black hole LMXBs could be concealed by a switch to radiatively inefficient accretion at low luminosities. The peak luminosity and the duration of X-ray binary outbursts are related to the disc radius and, hence, the orbital period. At short periods, where the peak outburst luminosity drops close to the threshold for radiatively inefficient accretion, black hole LMXBs have lower outburst luminosities, shorter outburst durations and lower X-ray duty cycles than comparable neutron star systems. These factors can combine to severely reduce the detection probability of short period black hole LMXBs relative to those containing neutron stars. We estimate the outburst properties and orbital period distribution of black hole LMXBs using two models of the transition to radiatively inefficient accretion: an instantaneous drop in accretion efficiency (η) to zero, at a fraction (f) of the Eddington luminosity (LEdd) and a power-law efficiency decrease, η ∝ dot{M}^n, for L < f LEdd. We show that a population of black hole LMXBs at short orbital periods can only be hidden by a sharp drop in efficiency, either instantaneous or for n ≳ 3. This could be achieved by a genuine drop in luminosity or through abrupt spectral changes that shift the accretion power out of a given X-ray band.

Effect of Schooling on Age-Disparate Relationships and Number of Sexual Partners Among Young Women in Rural South Africa Enrolled in HPTN 068.

PubMed

Stoner, Marie C D; Edwards, Jessie K; Miller, William C; Aiello, Allison E; Halpern, Carolyn T; Julien, Aimée; Selin, Amanda; Hughes, James P; Wang, Jing; Gomez-Olive, Francesc Xavier; Wagner, Ryan G; MacPhail, Catherine; Kahn, Kathleen; Pettifor, Audrey

2017-12-15

Attending school may have a strong preventative association with sexually transmitted infections among young women, but the mechanism for this relationship is unknown. One hypothesis is that students who attend school practice safer sex with fewer partners, establishing safer sexual networks that make them less exposed to infection. We used longitudinal data from a randomized controlled trial of young women aged 13-20 years in the Bushbuckridge district, South Africa, to determine whether the percentage of school days attended, school dropout, and grade repetition are associated with having a partner 5 or more years older (age-disparate) and with the number of sexual partners in the previous 12 months. Risks of having an age-disparate relationship and number of sexual partners were compared using inverse probability of exposure weighted Poisson regression models. Generalized estimating equations were used to account for repeated measures. Young women who attended fewer school days (<80%) and who dropped out of school were more likely to have an age-disparate relationship (risk difference 9.9%, 95% confidence interval [CI]: 3.9% to 16.0%; risk difference (%) dropout 17.2%, 95% CI: 5.4% to 29.0%) and those who dropped out reported having fewer partners (count difference dropout 0.343, 95% CI: 0.192 to 0.495). Grade repetition was not associated with either behavior. Young women who less frequently attend school or who drop out are more likely to have an age-disparate relationship. Young women who drop out have overall more partners. These behaviors may increase the risk of exposure to HIV infection in young women out of school.

Comparison of earthquake source characteristics in the Kachchh Rift Basin and Saurashtra horst, Deccan Volcanic Province, western India

NASA Astrophysics Data System (ADS)

Sairam, B.; Singh, A. P.; Ravi Kumar, M.

2018-06-01

Seismic source parameters of small to moderate sized intraplate earthquakes that occurred during 2002-2009 in the tectonic blocks of Kachchh Rift Basin (KRB) and the Saurashtra Horst (SH), in the stable continental region of western peninsular India, are studied through spectral analysis of shear waves. The data of aftershock sequence of the 2001 Bhuj earthquake (Mw 7.7) in the KRB and the 2007 Talala earthquake (Mw 5.0) in the SH are used for this study. In the SH, the seismic moment (Mo), corner frequency (fc), stress drop (Δ σ ) and source radius ( r) vary from 7.8× 10^{11} to 4.0× 10^{16} N-m, 1.0-8.9 Hz, 4.8-10.2 MPa and 195-1480 m, respectively. While in the KRB, these parameters vary from Mo ˜ 1.24 × 10^{11} to 4.1 × 10^{16} N-m, f_{c }˜ 1.6 to 13.1 Hz, Δ σ ˜ 0.06 to 16.62 MPa and r ˜ 100 to 840 m. The kappa ( K) value in the KRB (0.025-0.03) is slightly larger than that in the SH region (0.02), probably due to thick sedimentary layers. The estimated stress drops of earthquakes in the KRB are relatively higher than those in SH, due to large crustal stress concentration associated with mafic/ultramafic rocks at the hypocentral depths. The results also suggest that the stress drop value of intraplate earthquakes is larger than the interplate earthquakes. In addition, it is observed that the strike-slip events in the SH have lower stress drops, compared to the thrust and strike-slip events.

A formula for the entropy of the convolution of Gibbs probabilities on the circle

NASA Astrophysics Data System (ADS)

Lopes, Artur O.

2018-07-01

Consider the transformation , such that (mod 1), and where S 1 is the unitary circle. Suppose is Hölder continuous and positive, and moreover that, for any , we have that We say that ρ is a Gibbs probability for the Hölder continuous potential , if where is the Ruelle operator for . We call J the Jacobian of ρ. Suppose is the convolution of two Gibbs probabilities and associated, respectively, to and . We show that ν is also Gibbs and its Jacobian is given by . In this case, the entropy is given by the expression For a fixed we consider differentiable variations , , of on the Banach manifold of Gibbs probabilities, where , and we estimate the derivative of the entropy at t  =  0. We also present an expression for the Jacobian of the convolution of a Gibbs probability ρ with the invariant probability with support on a periodic orbit of period two. This expression is based on the Jacobian of ρ and two Radon–Nidodym derivatives.

EFFECTS OF RESPONDING TO A NAME AND GROUP CALL ON PRESCHOOLERS' COMPLIANCE

PubMed Central

Beaulieu, Lauren; Hanley, Gregory P.; Roberson, Aleasha A.

2012-01-01

We assessed teacher–child relations with respect to children's name calls, instructions, and compliance in a preschool classroom. The most frequent consequence to a child's name being called was the provision of instructions. We also observed a higher probability of compliance when children attended to a name call. Next, we evaluated the effects of teaching preschoolers to attend to their names and a group call on their compliance with typical instructions. We used a multiple baseline design across subjects and a control-group design to evaluate whether gains in compliance were a function of treatment or routine experience in preschool. Results showed that compliance increased as a function of teaching precursors for all children in the experimental group, and the effects on compliance were maintained despite a reduction of the occurrence of precursors. Moreover, it appeared that precursor teaching, not routine preschool experience, was responsible for the changes in compliance. PMID:23322926

Effects of responding to a name and group call on preschoolers' compliance.

PubMed

Beaulieu, Lauren; Hanley, Gregory P; Roberson, Aleasha A

2012-01-01

We assessed teacher-child relations with respect to children's name calls, instructions, and compliance in a preschool classroom. The most frequent consequence to a child's name being called was the provision of instructions. We also observed a higher probability of compliance when children attended to a name call. Next, we evaluated the effects of teaching preschoolers to attend to their names and a group call on their compliance with typical instructions. We used a multiple baseline design across subjects and a control-group design to evaluate whether gains in compliance were a function of treatment or routine experience in preschool. Results showed that compliance increased as a function of teaching precursors for all children in the experimental group, and the effects on compliance were maintained despite a reduction of the occurrence of precursors. Moreover, it appeared that precursor teaching, not routine preschool experience, was responsible for the changes in compliance.

Exploratory factor analysis of pathway copy number data with an application towards the integration with gene expression data.

PubMed

van Wieringen, Wessel N; van de Wiel, Mark A

2011-05-01

Realizing that genes often operate together, studies into the molecular biology of cancer shift focus from individual genes to pathways. In order to understand the regulatory mechanisms of a pathway, one must study its genes at all molecular levels. To facilitate such study at the genomic level, we developed exploratory factor analysis for the characterization of the variability of a pathway's copy number data. A latent variable model that describes the call probability data of a pathway is introduced and fitted with an EM algorithm. In two breast cancer data sets, it is shown that the first two latent variables of GO nodes, which inherit a clear interpretation from the call probabilities, are often related to the proportion of aberrations and a contrast of the probabilities of a loss and of a gain. Linking the latent variables to the node's gene expression data suggests that they capture the "global" effect of genomic aberrations on these transcript levels. In all, the proposed method provides an possibly insightful characterization of pathway copy number data, which may be fruitfully exploited to study the interaction between the pathway's DNA copy number aberrations and data from other molecular levels like gene expression.

Modelling the Probability of Landslides Impacting Road Networks

NASA Astrophysics Data System (ADS)

Taylor, F. E.; Malamud, B. D.

2012-04-01

During a landslide triggering event, the threat of landslides blocking roads poses a risk to logistics, rescue efforts and communities dependant on those road networks. Here we present preliminary results of a stochastic model we have developed to evaluate the probability of landslides intersecting a simple road network during a landslide triggering event and apply simple network indices to measure the state of the road network in the affected region. A 4000 x 4000 cell array with a 5 m x 5 m resolution was used, with a pre-defined simple road network laid onto it, and landslides 'randomly' dropped onto it. Landslide areas (AL) were randomly selected from a three-parameter inverse gamma probability density function, consisting of a power-law decay of about -2.4 for medium and large values of AL and an exponential rollover for small values of AL; the rollover (maximum probability) occurs at about AL = 400 m2 This statistical distribution was chosen based on three substantially complete triggered landslide inventories recorded in existing literature. The number of landslide areas (NL) selected for each triggered event iteration was chosen to have an average density of 1 landslide km-2, i.e. NL = 400 landslide areas chosen randomly for each iteration, and was based on several existing triggered landslide event inventories. A simple road network was chosen, in a 'T' shape configuration, with one road 1 x 4000 cells (5 m x 20 km) in a 'T' formation with another road 1 x 2000 cells (5 m x 10 km). The landslide areas were then randomly 'dropped' over the road array and indices such as the location, size (ABL) and number of road blockages (NBL) recorded. This process was performed 500 times (iterations) in a Monte-Carlo type simulation. Initial results show that for a landslide triggering event with 400 landslides over a 400 km2 region, the number of road blocks per iteration, NBL,ranges from 0 to 7. The average blockage area for the 500 iterations (A¯ BL) is about 3000 m2, which closely matches the value of A¯ L for the triggered landslide inventories. We further find that over the 500 iterations, the probability of a given number of road blocks occurring on any given iteration, p(NBL) as a function of NBL, follows reasonably well a three-parameter inverse gamma probability density distribution with an exponential rollover (i.e., the most frequent value) at NBL = 1.3. In this paper we have begun to calculate the probability of the number of landslides blocking roads during a triggering event, and have found that this follows an inverse-gamma distribution, which is similar to that found for the statistics of landslide areas resulting from triggers. As we progress to model more realistic road networks, this work will aid in both long-term and disaster management for road networks by allowing probabilistic assessment of road network potential damage during different magnitude landslide triggering event scenarios.

MIDAS: a practical Bayesian design for platform trials with molecularly targeted agents.

PubMed

Yuan, Ying; Guo, Beibei; Munsell, Mark; Lu, Karen; Jazaeri, Amir

2016-09-30

Recent success of immunotherapy and other targeted therapies in cancer treatment has led to an unprecedented surge in the number of novel therapeutic agents that need to be evaluated in clinical trials. Traditional phase II clinical trial designs were developed for evaluating one candidate treatment at a time and thus not efficient for this task. We propose a Bayesian phase II platform design, the multi-candidate iterative design with adaptive selection (MIDAS), which allows investigators to continuously screen a large number of candidate agents in an efficient and seamless fashion. MIDAS consists of one control arm, which contains a standard therapy as the control, and several experimental arms, which contain the experimental agents. Patients are adaptively randomized to the control and experimental agents based on their estimated efficacy. During the trial, we adaptively drop inefficacious or overly toxic agents and 'graduate' the promising agents from the trial to the next stage of development. Whenever an experimental agent graduates or is dropped, the corresponding arm opens immediately for testing the next available new agent. Simulation studies show that MIDAS substantially outperforms the conventional approach. The proposed design yields a significantly higher probability for identifying the promising agents and dropping the futile agents. In addition, MIDAS requires only one master protocol, which streamlines trial conduct and substantially decreases the overhead burden. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

MIDAS: A Practical Bayesian Design for Platform Trials with Molecularly Targeted Agents

PubMed Central

Yuan, Ying; Guo, Beibei; Munsell, Mark; Lu, Karen; Jazaeri, Amir

2016-01-01

Recent success of immunotherapy and other targeted therapies in cancer treatment has led to an unprecedented surge in the number of novel therapeutic agents that need to be evaluated in clinical trials. Traditional phase II clinical trial designs were developed for evaluating one candidate treatment at a time, and thus not efficient for this task. We propose a Bayesian phase II platform design, the Multi-candidate Iterative Design with Adaptive Selection (MIDAS), which allows investigators to continuously screen a large number of candidate agents in an efficient and seamless fashion. MIDAS consists of one control arm, which contains a standard therapy as the control, and several experimental arms, which contain the experimental agents. Patients are adaptively randomized to the control and experimental agents based on their estimated efficacy. During the trial, we adaptively drop inefficacious or overly toxic agents and “graduate” the promising agents from the trial to the next stage of development. Whenever an experimental agent graduates or is dropped, the corresponding arm opens immediately for testing the next available new agent. Simulation studies show that MIDAS substantially outperforms the conventional approach. The proposed design yields a significantly higher probability for identifying the promising agents and dropping the futile agents. In addition, MIDAS requires only one master protocol, which streamlines trial conduct and substantially decreases the overhead burden. PMID:27112322

The Statistical Loop Analyzer (SLA)

NASA Technical Reports Server (NTRS)

Lindsey, W. C.

1985-01-01

The statistical loop analyzer (SLA) is designed to automatically measure the acquisition, tracking and frequency stability performance characteristics of symbol synchronizers, code synchronizers, carrier tracking loops, and coherent transponders. Automated phase lock and system level tests can also be made using the SLA. Standard baseband, carrier and spread spectrum modulation techniques can be accomodated. Through the SLA's phase error jitter and cycle slip measurements the acquisition and tracking thresholds of the unit under test are determined; any false phase and frequency lock events are statistically analyzed and reported in the SLA output in probabilistic terms. Automated signal drop out tests can be performed in order to trouble shoot algorithms and evaluate the reacquisition statistics of the unit under test. Cycle slip rates and cycle slip probabilities can be measured using the SLA. These measurements, combined with bit error probability measurements, are all that are needed to fully characterize the acquisition and tracking performance of a digital communication system.

How frequently do allegations of scientific misconduct occur in ecology and evolution, and what happens afterwards?

PubMed

Moreno-Rueda, Gregorio

2013-03-01

Scientific misconduct obstructs the advance of knowledge in science. Its impact in some disciplines is still poorly known, as is the frequency in which it is detected. Here, I examine how frequently editors of ecology and evolution journals detect scientist misconduct. On average, editors managed 0.114 allegations of misconduct per year. Editors considered 6 of 14 allegations (42.9%) to be true, but only in 2 cases were the authors declared guilty, the remaining being dropped for lack of proof. The annual rate of allegations that were probably warranted was 0.053, although the rate of demonstrated misconduct was 0.018, while the rate of false or erroneous allegations was 0.024. Considering that several cases of misconduct are probably not reported, these findings suggest that editors detect less than one-third of all fraudulent papers.

Minimum Income Allocation System (RMI): a longitudinal view.

PubMed

Cordazzo, Philippe

2005-10-01

In 2000, for the first time, the number of minimum income allocation system (RMI) recipients decreased. In 2001, this drop in the number of recipients began to stabilize, and the number started to increase again in 2002. The author observed a stabilization of the number of new recipients, whereas the number of exits decreased. This situation is different according to local countries (departments). The probability of RMI entries is more important for populations living in the south and southeast of France. RMI recipients of the more recent cohorts leave more quickly and in proportion more significantly than do the recipients of the older cohorts. This phenomenon is alarming because the exits occur massively during the first 2 years spent in the RMI device and because the probability of leaving decreases sharply. The author has thus observed that a significant portion of the recipients (28%) is present after 5 years or more in the RMI device.

Analytical study of nano-scale logical operations

NASA Astrophysics Data System (ADS)

Patra, Moumita; Maiti, Santanu K.

2018-07-01

A complete analytical prescription is given to perform three basic (OR, AND, NOT) and two universal (NAND, NOR) logic gates at nano-scale level using simple tailor made geometries. Two different geometries, ring-like and chain-like, are taken into account where in each case the bridging conductor is coupled to a local atomic site through a dangling bond whose site energy can be controlled by means of external gate electrode. The main idea is that when injecting electron energy matches with site energy of local atomic site transmission probability drops exactly to zero, whereas the junction exhibits finite transmission for other energies. Utilizing this prescription we perform logical operations, and, we strongly believe that the proposed results can be verified in laboratory. Finally, we numerically compute two-terminal transmission probability considering general models and the numerical results match exactly well with our analytical findings.

Puberty and the Education of Girls*

PubMed Central

CAVANAGH, SHANNON E.; RIEGLE-CRUMB, CATHERINE; CROSNOE, ROBERT

2010-01-01

This study extends previous research on the social psychological implications of pubertal timing to education by applying a life course framework to data from the National Longitudinal Study of Adolescent Health and from the Adolescent Health and Academic Achievement Study. Early pubertal timing, which has previously been associated with major social psychological changes in girls' lives during middle school, predicted girls' grade point average and probability of course failure at the start of high school. Because of this initial failure during the high school transition, it also predicted their probability of dropping out of high school, and, among those who graduated, their grade point average at the end of high school. Such research demonstrates one way in which the immediate social psychological risk of early pubertal timing, measured as the age at menarche, translates into long-term disadvantage for girls, thereby opening up new avenues of research for social psychologists interested in youth development, health, and education. PMID:20216926

A Scalable QoS-Aware VoD Resource Sharing Scheme for Next Generation Networks

NASA Astrophysics Data System (ADS)

Huang, Chenn-Jung; Luo, Yun-Cheng; Chen, Chun-Hua; Hu, Kai-Wen

In network-aware concept, applications are aware of network conditions and are adaptable to the varying environment to achieve acceptable and predictable performance. In this work, a solution for video on demand service that integrates wireless and wired networks by using the network aware concepts is proposed to reduce the blocking probability and dropping probability of mobile requests. Fuzzy logic inference system is employed to select appropriate cache relay nodes to cache published video streams and distribute them to different peers through service oriented architecture (SOA). SIP-based control protocol and IMS standard are adopted to ensure the possibility of heterogeneous communication and provide a framework for delivering real-time multimedia services over an IP-based network to ensure interoperability, roaming, and end-to-end session management. The experimental results demonstrate that effectiveness and practicability of the proposed work.

Neck curve polynomials in neck rupture model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurniadi, Rizal; Perkasa, Yudha S.; Waris, Abdul

2012-06-06

The Neck Rupture Model is a model that explains the scission process which has smallest radius in liquid drop at certain position. Old fashion of rupture position is determined randomly so that has been called as Random Neck Rupture Model (RNRM). The neck curve polynomials have been employed in the Neck Rupture Model for calculation the fission yield of neutron induced fission reaction of {sup 280}X{sub 90} with changing of order of polynomials as well as temperature. The neck curve polynomials approximation shows the important effects in shaping of fission yield curve.

Reduced Order Modeling For High Speed Flows with Moving Shocks

DTIC Science & Technology

2001-12-03

critical values of Q are the values of U and λ such that G(y) = dQ(y) dy =   F (U) + λ dC(U) dU C(U)   = [0]. (2.28) As long as the constraints ...by adding each linear constraint as shown in equation (5.6) (the n + 1 superscript on US is dropped for convenience). This new functional Q , called...Institute of Technology, School of Engineering and Man- agement, 2001. 49. Naylor, Arch W. and Sell, George R. Linear Operator Theory in Engineering and

Lenz's Law Magic Trick

NASA Astrophysics Data System (ADS)

Ruiz, Michael J.

2006-02-01

The demonstration of Lenz's law by dropping a powerful magnet down a nonmagnetic metal pipe has become a classic lecture-hall demonstration.1,2 An inexpensive version is packaged as a professional magic trick3 called "Newton's Nightmare." Combining sleight-of-hand with a demonstration of Lenz's law is a surefire way to heighten student interest. The subsequent student discussion motivated by a desire to understand the magic trick can lead to a memorable physics lesson. This paper will discuss Lenz's law magic and review literature that reveals the subtlety of the physics.

A simple process to achieve microchannels geometries able to produce hydrodynamic cavitation

NASA Astrophysics Data System (ADS)

Qiu, X.; Cherief, W.; Colombet, D.; Ayela, F.

2017-04-01

We present a simple process to perform microchannels in which cavitating two phase flows are easily producible. Up to now, hydrodynamic cavitation ‘on a chip’ was reached with small flow rates inside microchannels whose micromachining had involved a deep reactive ion etching (D-RIE). The process we present here does not require a D-RIE reactor, as it is only funded on a wet etching of silicon. It leads to a so-called microstep profile, and large cavitating flow rates become possible together with moderate pressure drops.

Reliability and the adaptive utility of discrimination among alarm callers.

PubMed

Blumstein, Daniel T; Verneyre, Laure; Daniel, Janice C

2004-09-07

Unlike individually distinctive contact calls, or calls that aid in the recognition of young by their parents, the function or functions of individually distinctive alarm calls is less obvious. We conducted three experiments to study the importance of caller reliability in explaining individual-discriminative abilities in the alarm calls of yellow-bellied marmots (Marmota flaviventris). In our first two experiments, we found that calls from less reliable individuals and calls from individuals calling from a greater simulated distance were more evocative than calls from reliable individuals or nearby callers. These results are consistent with the hypothesis that marmots assess the reliability of callers to help them decide how much time to allocate to independent vigilance. The third experiment demonstrated that the number of callers influenced responsiveness, probably because situations where more than a single caller calls, are those when there is certain to be a predator present. Taken together, the results from all three experiments demonstrate the importance of reliability in explaining individual discrimination abilities in yellow-bellied marmots. Marmots' assessment of reliability acts by influencing the time allocated to individual assessment and thus the time not allocated to other activities.

Reliability and the adaptive utility of discrimination among alarm callers.

PubMed Central

Blumstein, Daniel T.; Verneyre, Laure; Daniel, Janice C.

2004-01-01

Unlike individually distinctive contact calls, or calls that aid in the recognition of young by their parents, the function or functions of individually distinctive alarm calls is less obvious. We conducted three experiments to study the importance of caller reliability in explaining individual-discriminative abilities in the alarm calls of yellow-bellied marmots (Marmota flaviventris). In our first two experiments, we found that calls from less reliable individuals and calls from individuals calling from a greater simulated distance were more evocative than calls from reliable individuals or nearby callers. These results are consistent with the hypothesis that marmots assess the reliability of callers to help them decide how much time to allocate to independent vigilance. The third experiment demonstrated that the number of callers influenced responsiveness, probably because situations where more than a single caller calls, are those when there is certain to be a predator present. Taken together, the results from all three experiments demonstrate the importance of reliability in explaining individual discrimination abilities in yellow-bellied marmots. Marmots' assessment of reliability acts by influencing the time allocated to individual assessment and thus the time not allocated to other activities. PMID:15315902

Responses of male cricket frogs (Acris crepitans) to attenuated and degraded advertisement calls.

PubMed

Venator, Kurt R; Ryan, Michael J; Wilczynski, Walter

2017-05-01

We examined the vocal and non-vocal responses of male cricket frogs ( Acris crepitans ) to conspecific advertisement calls that had been attenuated or degraded by reducing the depth of amplitude modulation (AM). Both are characteristic of changes to the call as it is transmitted through natural habitats. As stimulus calls became more intense or less degraded, male cricket frogs gradually decreased their call rate and increased the number of call groups and pulse groups in their calls, changes indicative of increased aggressive interactions. At the higher intensities and lower degradation levels, the probability that males would shift to one of two non-vocal behavioral responses, attacking the perceived intruder or ceasing calling and abandoning the call site, gradually increased. The results show that differences in signal attenuation and AM degradation levels are perceived by males and trigger both vocal and non-vocal behavioral responses consistent with their use in evaluating the distance to a challenging male. Furthermore, the results indicate that the male responses are graded, increasing as intensity rises and degradation falls, and hierarchical, with vocal responses preceding behavioral responses over the range of intensities and degradation levels presented.

Responses of male cricket frogs (Acris crepitans) to attenuated and degraded advertisement calls

PubMed Central

Venator, Kurt R.; Ryan, Michael J.; Wilczynski, Walter

2017-01-01

We examined the vocal and non-vocal responses of male cricket frogs (Acris crepitans) to conspecific advertisement calls that had been attenuated or degraded by reducing the depth of amplitude modulation (AM). Both are characteristic of changes to the call as it is transmitted through natural habitats. As stimulus calls became more intense or less degraded, male cricket frogs gradually decreased their call rate and increased the number of call groups and pulse groups in their calls, changes indicative of increased aggressive interactions. At the higher intensities and lower degradation levels, the probability that males would shift to one of two non-vocal behavioral responses, attacking the perceived intruder or ceasing calling and abandoning the call site, gradually increased. The results show that differences in signal attenuation and AM degradation levels are perceived by males and trigger both vocal and non-vocal behavioral responses consistent with their use in evaluating the distance to a challenging male. Furthermore, the results indicate that the male responses are graded, increasing as intensity rises and degradation falls, and hierarchical, with vocal responses preceding behavioral responses over the range of intensities and degradation levels presented. PMID:28966421

Probability of pregnancy after sterilization: a comparison of hysteroscopic versus laparoscopic sterilization.

PubMed

Gariepy, Aileen M; Creinin, Mitchell D; Smith, Kenneth J; Xu, Xiao

2014-08-01

To compare the expected probability of pregnancy after hysteroscopic versus laparoscopic sterilization based on available data using decision analysis. We developed an evidence-based Markov model to estimate the probability of pregnancy over 10 years after three different female sterilization procedures: hysteroscopic, laparoscopic silicone rubber band application and laparoscopic bipolar coagulation. Parameter estimates for procedure success, probability of completing follow-up testing and risk of pregnancy after different sterilization procedures were obtained from published sources. In the base case analysis at all points in time after the sterilization procedure, the initial and cumulative risk of pregnancy after sterilization is higher in women opting for hysteroscopic than either laparoscopic band or bipolar sterilization. The expected pregnancy rates per 1000 women at 1 year are 57, 7 and 3 for hysteroscopic sterilization, laparoscopic silicone rubber band application and laparoscopic bipolar coagulation, respectively. At 10 years, the cumulative pregnancy rates per 1000 women are 96, 24 and 30, respectively. Sensitivity analyses suggest that the three procedures would have an equivalent pregnancy risk of approximately 80 per 1000 women at 10 years if the probability of successful laparoscopic (band or bipolar) sterilization drops below 90% and successful coil placement on first hysteroscopic attempt increases to 98% or if the probability of undergoing a hysterosalpingogram increases to 100%. Based on available data, the expected population risk of pregnancy is higher after hysteroscopic than laparoscopic sterilization. Consistent with existing contraceptive classification, future characterization of hysteroscopic sterilization should distinguish "perfect" and "typical" use failure rates. Pregnancy probability at 1 year and over 10 years is expected to be higher in women having hysteroscopic as compared to laparoscopic sterilization. Copyright © 2014 Elsevier Inc. All rights reserved.

Impact, thermal, and shock sensitivity of molten TNT and of asphalt-contaminated molten TNT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mainiero, R.J.; Miron, Y.; Kwak, S.S.W.

1996-12-01

The research reported here was part of an effort to evaluate the safety of a process to recover TNT from MK-9 depth bombs by the autoclave meltout process. In this process the depth bombs are heated to 121 C so that the TNT will melt and run into a vat. Unfortunately, asphalt lining the inside surface of the bomb also melts and flows out with the TNT. Testing was conducted on molten TNT and molten TNT contaminated with 2 pct asphalt at 90, 100, 110, 120, 125, and 130 C. In the liquid drop test apparatus with a 2-kg weight,more » the molten TNT yielded a 50 pct probability of initiation at a drop height of 6.5 cm at 110 C, decreasing to 4.5 cm at 130 C. Asphalt-contaminated TNT was somewhat less impact-sensitive than pure TNT at temperatures of 110 to 125 C, but became more sensitive at 130 C. There is a 50 pct probability of initiation at a drop height of 7.8 cm at 110 C, decreasing to 3.3 cm at 130 C. In the card gap test, the molten TNT detonated at high velocity for a gap of 0.25 inches at 90 to 125 C and detonated at high velocity for a gap of 0.5 inches at 130 C. For gaps of 0.5 to 3 inches at 90 to 125 C and 0.75 inches to 3 inches at 130 C, the TNT did not detonate at high velocity but produced a violent explosion that caused significant damage to the test fixture. The thermal analysis test results showed that when asphalt is present in TNT, it greatly accelerates the exothermic decomposition of TNT, starting at temperatures near 200 C. It appears that at relatively low shock stimulus levels, the molten TNT may be undergoing a low velocity detonation, wherein the shock wave traveling through the gap test pipe cavitates the molten TNT, greatly increasing its sensitivity. These results are crucial for assuring continued safety in recovering TNT from munitions through the autoclave meltout process.« less

Glider-based Passive Acoustic Monitoring Techniques in the Southern California Region & West Coast Naval Training Range Demonstration of Glider-based Passive Acoustic Monitoring

DTIC Science & Technology

2012-09-30

generalized power-law detection algorithm for humpback whale vocalizations. J. Acous. Soc. Am. 131(4), 2682-2699. Roch, M. A., H. Klinck, S...Heaney (2012b). Site specific probability of passive acoustic detection of humpback whale calls from single fixed hydrophones. J. Acous. Soc. Am...monitoring: Correcting humpback call detections for site-specific and time-dependent environmental characteristics . JASA Express Letters, submitted October, 2012, 5 pgs plus 3 figs.

Bidirectional QoS support for novelty detection applications based on hierarchical wireless sensor network model

NASA Astrophysics Data System (ADS)

Edwards, Mark; Hu, Fei; Kumar, Sunil

2004-10-01

The research on the Novelty Detection System (NDS) (called as VENUS) at the authors' universities has generated exciting results. For example, we can detect an abnormal behavior (such as cars thefts from the parking lot) from a series of video frames based on the cognitively motivated theory of habituation. In this paper, we would like to describe the implementation strategies of lower layer protocols for using large-scale Wireless Sensor Networks (WSN) to NDS with Quality-of-Service (QoS) support. Wireless data collection framework, consisting of small and low-power sensor nodes, provides an alternative mechanism to observe the physical world, by using various types of sensing capabilities that include images (and even videos using Panoptos), sound and basic physical measurements such as temperature. We do not want to lose any 'data query command' packets (in the downstream direction: sink-to-sensors) or have any bit-errors in them since they are so important to the whole sensor network. In the upstream direction (sensors-to-sink), we may tolerate the loss of some sensing data packets. But the 'interested' sensing flow should be assigned a higher priority in terms of multi-hop path choice, network bandwidth allocation, and sensing data packet generation frequency (we hope to generate more sensing data packet for that novel event in the specified network area). The focus of this paper is to investigate MAC-level Quality of Service (QoS) issue in Wireless Sensor Networks (WSN) for Novelty Detection applications. Although QoS has been widely studied in other types of networks including wired Internet, general ad hoc networks and mobile cellular networks, we argue that QoS in WSN has its own characteristics. In wired Internet, the main QoS parameters include delay, jitter and bandwidth. In mobile cellular networks, two most common QoS metrics are: handoff call dropping probability and new call blocking probability. Since the main task of WSN is to detect and report events, the most important QoS parameters should include sensing data packet transmission reliability, lifetime extension degree from sensor sleeping control, event detection latency, congestion reduction level through removal of redundant sensing data. In this paper, we will focus on the following bi-directional QoS topics: (1) Downstream (sink-to-sensor) QoS: Reliable data query command forwarding to particular sensor(s). In other words, we do not want to lose the query command packets; (2) Upstream (sensor-to-sink) QoS: transmission of sensed data with priority control. The more interested data that can help in novelty detection should be transmitted on an optimal path with higher reliability. We propose the use of Differentiated Data Collection. Due to the large-scale nature and resource constraints of typical wireless sensor networks, such as limited energy, small memory (typically RAM < 4K bytes) and short communication range, the above problems become even more challenging. Besides QoS support issue, we will also describe our low-energy Sensing Data Transmission network Architecture. Our research results show the scalability and energy-efficiency of our proposed WSN QoS schemes.

An audit of environmental health calls to a department of public health medicine.

PubMed

Chappel, D; Fernandes, V

1995-11-01

To audit telephone calls concerning general issues in communicable disease control and environmental health to a department of public health medicine. A department of public health medicine in a district with a population of 190,000 during 1993. A retrospective audit of forms designed to record all calls concerning environmental health and communicable disease control. The intervention was a change in design of forms and education of doctors dealing with the calls. A re-audit was done after these changes had been implemented. The number of recorded calls increased from 1.75 (1992) to 3.29 (mid-1993) per week. Signing of forms increased from 61% to 83% and dating from 6% to 72%. All forms filled in by registrars or senior registrars were reviewed by the Consultant in Communicable Disease Control (CCDC). Very few calls were considered to be inappropriate. The increase in the number of calls was probably artefactual owing to better recording as a result of the audit. Improved recording will help in future training and audit, and be a medico-legal safeguard.

Dawn HAMO Image 63

NASA Image and Video Library

2015-11-19

This image of Ceres from NASA's Dawn spacecraft shows hummocky terrain -- a surface covered in low, rounded hills -- with numerous impact craters of varying sizes. The two biggest craters display central peaks and many places where masses of material have collapsed and slid downward along their walls and floors -- a phenomenon geologists call "mass wasting". The sharp crater at upper right is surrounded by smooth ejecta with a streaky texture to the south. A graben -- what geologists call a linear feature where terrain has dropped -- measuring 2 to 5 miles (3 to 8 kilometers) in width, and two prominent scarps, or linear, cliff-like slopes, are located in the southeastern (lower right) part of the image. Dawn took this image on Oct. 5, 2015, from an altitude of 915 miles (1,470 kilometers). It has a resolution of 450 feet (140 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20125

Wet Lab Accelerator: A Web-Based Application Democratizing Laboratory Automation for Synthetic Biology.

PubMed

Bates, Maxwell; Berliner, Aaron J; Lachoff, Joe; Jaschke, Paul R; Groban, Eli S

2017-01-20

Wet Lab Accelerator (WLA) is a cloud-based tool that allows a scientist to conduct biology via robotic control without the need for any programming knowledge. A drag and drop interface provides a convenient and user-friendly method of generating biological protocols. Graphically developed protocols are turned into programmatic instruction lists required to conduct experiments at the cloud laboratory Transcriptic. Prior to the development of WLA, biologists were required to write in a programming language called "Autoprotocol" in order to work with Transcriptic. WLA relies on a new abstraction layer we call "Omniprotocol" to convert the graphical experimental description into lower level Autoprotocol language, which then directs robots at Transcriptic. While WLA has only been tested at Transcriptic, the conversion of graphically laid out experimental steps into Autoprotocol is generic, allowing extension of WLA into other cloud laboratories in the future. WLA hopes to democratize biology by bringing automation to general biologists.

Design and implementation of a telemedicine system using Bluetooth protocol and GSM/GPRS network, for real time remote patient monitoring.

PubMed

Jasemian, Yousef; Nielsen, Lars Arendt

2005-01-01

This paper introduces the design and implementation of a generic wireless and Real-time Multi-purpose Health Care Telemedicine system applying Bluetooth protocol, Global System for Mobile Communications (GSM) and General Packet Radio Service (GPRS). The paper explores the factors that should be considered when evaluating different technologies for application in telemedicine system. The design and implementation of an embedded wireless communication platform utilising Bluetooth protocol is described, and the implementation problems and limitations are investigated. The system is tested and its telecommunication general aspects are verified. The results showed that the system has (97.9 +/- 1.3)% Up-time, 2.5 x 10(-5) Bit Error Rate, 1% Dropped Call Rate, 97.4% Call Success Rate, 5 second transmission delay in average, (3.42 +/- 0.11) kbps throughput, and the system may have application in electrocardiography.

Long-term engagement in smoking cessation counseling among rural smokers.

PubMed

Cupertino, A Paula; Mahnken, Jonathan D; Richter, Kimber; Cox, Lisa Sanderson; Casey, Genevieve; Resnicow, Ken; Ellerbeck, Edward F

2007-11-01

Effective smoking cessation treatment requires active patient engagement. This may be particularly important for rural smokers who have less access to smoking cessation resources than others. This study describes long-term engagement in counseling for smoking cessation and factors associated with engagement. As part of a randomized trial, 231 rural smokers received up to 6 telephone-based counseling sessions at 6-month intervals over 24 months. Engagement in treatment was categorized according to the number of counseling calls each interval. During the final 6-month interval, more than 60% of continuing smokers remained engaged in treatment. Call completion varied over time; while levels of engagement dropped after the first interval, many continuing smokers remained engaged throughout the study. Education, age, motivation, income, diabetes, and health insurance status were predictors of treatment engagement. This study demonstrates that smokers will remain engaged in long-term counseling designed to address the chronic nature of nicotine dependence.

A perspective on the interfacial properties of nanoscopic liquid drops.

PubMed

Malijevský, Alexandr; Jackson, George

2012-11-21

The structural and interfacial properties of nanoscopic liquid drops are assessed by means of mechanical, thermodynamical, and statistical mechanical approaches that are discussed in detail, including original developments at both the macroscopic level and the microscopic level of density functional theory (DFT). With a novel analysis we show that a purely macroscopic (static) mechanical treatment can lead to a qualitatively reasonable description of the surface tension and the Tolman length of a liquid drop; the latter parameter, which characterizes the curvature dependence of the tension, is found to be negative and has a magnitude of about a half of the molecular dimension. A mechanical slant cannot, however, be considered satisfactory for small finite-size systems where fluctuation effects are significant. From the opposite perspective, a curvature expansion of the macroscopic thermodynamic properties (density and chemical potential) is then used to demonstrate that a purely thermodynamic approach of this type cannot in itself correctly account for the curvature correction of the surface tension of liquid drops. We emphasize that any approach, e.g., classical nucleation theory, which is based on a purely macroscopic viewpoint, does not lead to a reliable representation when the radius of the drop becomes microscopic. The description of the enhanced inhomogeneity exhibited by small drops (particularly in the dense interior) necessitates a treatment at the molecular level to account for finite-size and surface effects correctly. The so-called mechanical route, which corresponds to a molecular-level extension of the macroscopic theory of elasticity and is particularly popular in molecular dynamics simulation, also appears to be unreliable due to the inherent ambiguity in the definition of the microscopic pressure tensor, an observation which has been known for decades but is frequently ignored. The union of the theory of capillarity (developed in the nineteenth century by Gibbs and then promoted by Tolman) with a microscopic DFT treatment allows for a direct and unambiguous description of the interfacial properties of drops of arbitrary size; DFT provides all of the bulk and surface characteristics of the system that are required to uniquely define its thermodynamic properties. In this vein, we propose a non-local mean-field DFT for Lennard-Jones (LJ) fluids to examine drops of varying size. A comparison of the predictions of our DFT with recent simulation data based on a second-order fluctuation analysis (Sampayo et al 2010 J. Chem. Phys. 132 141101) reveals the consistency of the two treatments. This observation highlights the significance of fluctuation effects in small drops, which give rise to additional entropic (thermal non-mechanical) contributions, in contrast to what one observes in the case of planar interfaces which are governed by the laws of mechanical equilibrium. A small negative Tolman length (which is found to be about a tenth of the molecular diameter) and a non-monotonic behaviour of the surface tension with the drop radius are predicted for the LJ fluid. Finally, the limits of the validity of the Tolman approach, the effect of the range of the intermolecular potential, and the behaviour of bubbles are briefly discussed.

Burial duration, depth and air pocket explain avalanche survival patterns in Austria and Switzerland.

PubMed

Procter, Emily; Strapazzon, Giacomo; Dal Cappello, Tomas; Zweifel, Benjamin; Würtele, Andreas; Renner, Andreas; Falk, Markus; Brugger, Hermann

2016-08-01

To calculate the first Austrian avalanche survival curve and update a Swiss survival curve to explore survival patterns in the Alps. Avalanche accidents occurring between 2005/06 and 2012/13 in Austria and Switzerland were collected. Completely buried victims (i.e. burial of the head and chest) in open terrain with known outcome (survived or not survived) were included in the analysis. Extrication and survival curves were calculated using the Turnbull algorithm, as in previous studies. 633 of the 796 completely buried victims were included (Austria n=333, Switzerland n=300). Overall survival was 56% (Austria 59%; Switzerland 52%; p=0.065). Time to extrication was shorter in Austria for victims buried ≤60min (p<0.001). The survival curves were similar and showed a rapid initial drop in survival probability and a second drop to 25-28% survival probability after burial duration of ca. 35min, where an inflection point exists and the curve levels off. In a logistic regression analysis, both duration of burial and burial depth had an independent effect on survival. Victims with an air pocket were more likely to survive, especially if buried >15min. The survival curves resembled those previously published and support the idea that underlying survival patterns are reproducible. The results are in accordance with current recommendations for management of avalanche victims and serve as a reminder that expedient companion rescue within a few minutes is critical for survival. An air pocket was shown to be a positive prognostic factor for survival. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Using the Reliability Theory for Assessing the Decision Confidence Probability for Comparative Life Cycle Assessments.

PubMed

Wei, Wei; Larrey-Lassalle, Pyrène; Faure, Thierry; Dumoulin, Nicolas; Roux, Philippe; Mathias, Jean-Denis

2016-03-01

Comparative decision making process is widely used to identify which option (system, product, service, etc.) has smaller environmental footprints and for providing recommendations that help stakeholders take future decisions. However, the uncertainty problem complicates the comparison and the decision making. Probability-based decision support in LCA is a way to help stakeholders in their decision-making process. It calculates the decision confidence probability which expresses the probability of a option to have a smaller environmental impact than the one of another option. Here we apply the reliability theory to approximate the decision confidence probability. We compare the traditional Monte Carlo method with a reliability method called FORM method. The Monte Carlo method needs high computational time to calculate the decision confidence probability. The FORM method enables us to approximate the decision confidence probability with fewer simulations than the Monte Carlo method by approximating the response surface. Moreover, the FORM method calculates the associated importance factors that correspond to a sensitivity analysis in relation to the probability. The importance factors allow stakeholders to determine which factors influence their decision. Our results clearly show that the reliability method provides additional useful information to stakeholders as well as it reduces the computational time.

Simple artificial neural networks that match probability and exploit and explore when confronting a multiarmed bandit.

PubMed

Dawson, Michael R W; Dupuis, Brian; Spetch, Marcia L; Kelly, Debbie M

2009-08-01

The matching law (Herrnstein 1961) states that response rates become proportional to reinforcement rates; this is related to the empirical phenomenon called probability matching (Vulkan 2000). Here, we show that a simple artificial neural network generates responses consistent with probability matching. This behavior was then used to create an operant procedure for network learning. We use the multiarmed bandit (Gittins 1989), a classic problem of choice behavior, to illustrate that operant training balances exploiting the bandit arm expected to pay off most frequently with exploring other arms. Perceptrons provide a medium for relating results from neural networks, genetic algorithms, animal learning, contingency theory, reinforcement learning, and theories of choice.

Reducing calls missed by the hospital telephone exchange from 26% to less than 10.

PubMed

Bhartia, Saru; Bahlvi, Zorba; Sharma, Irina

2016-01-01

A hospital's telephone exchange is the first point of contact for patients and their attendants to take appointments, to collect healthcare related information and to connect to the hospital in case of emergencies. At Sitaram Bhartia Institute of Science and Research the doctors, patients, and attendants often complained about the inefficiency of the hospital exchange. In February 2012, a doctor raised her concern of calls not being picked up at the exchange with the senior management and a QI project was initiated to tackle the problem. Baseline data showed that about 26% of incoming calls to the hospital during 8am to 8pm were not being picked up. On the basis of the baseline data, call audits, staff interviews, and observations the project team identified the defects. These defects were categorized under four headings - manpower, equipment, processes, and environment. The team proposed several change ideas. Some of these change ideas were implemented immediately. Three proposed change ideas were tested through individual PDSA cycles. The percentage of missed calls dropped from 26% to 18.1% after the first cycle and then to 9.6% and 6.5% after the subsequent cycles which involved testing of two other additional change ideas. These changes were implemented and a benchmark of no more than 10% calls to be missed was set. For nearly three years we have held the gains and have met the benchmark of missing not more than 10% calls coming to the hospital exchange between 8am to 8pm. The contributing factors to the success have been the involvement of frontline workers, an expert and engaged head of department, and senior leadership support.

Defining Baconian Probability for Use in Assurance Argumentation

NASA Technical Reports Server (NTRS)

Graydon, Patrick J.

2016-01-01

The use of assurance cases (e.g., safety cases) in certification raises questions about confidence in assurance argument claims. Some researchers propose to assess confidence in assurance cases using Baconian induction. That is, a writer or analyst (1) identifies defeaters that might rebut or undermine each proposition in the assurance argument and (2) determines whether each defeater can be dismissed or ignored and why. Some researchers also propose denoting confidence using the counts of defeaters identified and eliminated-which they call Baconian probability-and performing arithmetic on these measures. But Baconian probabilities were first defined as ordinal rankings which cannot be manipulated arithmetically. In this paper, we recount noteworthy definitions of Baconian induction, review proposals to assess confidence in assurance claims using Baconian probability, analyze how these comport with or diverge from the original definition, and make recommendations for future practice.

Probability and Statistics in Sensor Performance Modeling

DTIC Science & Technology

2010-12-01

language software program is called Environmental Awareness for Sensor and Emitter Employment. Some important numerical issues in the implementation...3 Statistical analysis for measuring sensor performance...complementary cumulative distribution function cdf cumulative distribution function DST decision-support tool EASEE Environmental Awareness of

Imaging Tests for Lower Back Pain: When You Need Them -- and When You Don't

MedlinePlus

... Geriatric Imaging Tests for Lower-Back Back Pain Imaging Tests for Lower-Back Pain You probably do ... X-rays, CT scans, and MRIs are called imaging tests because they take pictures, or images, of ...

The last scream: the distress call of a probably extinct Brazilian anuran (Holoaden bradei Lutz, 1958).

PubMed

Martinelli, Amanda; Toledo, Luís Felipe

2016-11-03

The genus Holoaden Miranda-Ribeiro (Anura, Craugastoridae, Holoadeninae) includes four species endemic to the southeastern Brazilian Atlantic Forest, which occur in cloud forests at high elevations (Lutz 1958, Pombal et al. 2008, Martins & Zaher 2013). Out of these, two species are considered threatened by Ministério do Meio Ambiente (2014): H. bradei is classified as critically endangered (CR) and H. luederwaldti as endangered (EN). Holoaden bradei might be already extinct in the wild, as it has not been recorded in the last 40 years in spite of intense scientific activity within its original distribution range (Rocha & van Sluys 2004). The advertisement call has been described only for Holoaden luederwaldti (Martins 2010). Call descriptions, especially of advertisement calls, are important sources of evidence in taxonomic and phylogenetic studies (Roy 1996, Toledo et al. 2007, Andrade et al. 2016). However, there are other call types (see classification in Toledo et al. 2015) that can be used in absence of advertisement calls (e.g., Grenat & Martino 2013). We recently had access to a recording made in 1960's of the distress call of H. bradei. We hereby describe this call.

Light in condensed matter in the upper atmosphere as the origin of homochirality: circularly polarized light from Rydberg matter.

PubMed

Holmlid, Leif

2009-01-01

Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

Light in Condensed Matter in the Upper Atmosphere as the Origin of Homochirality: Circularly Polarized Light from Rydberg Matter

NASA Astrophysics Data System (ADS)

Holmlid, Leif

2009-08-01

Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

Shape of growth-rate distribution determines the type of Non-Gibrat’s Property

NASA Astrophysics Data System (ADS)

Ishikawa, Atushi; Fujimoto, Shouji; Mizuno, Takayuki

2011-11-01

In this study, the authors examine exhaustive business data on Japanese firms, which cover nearly all companies in the mid- and large-scale ranges in terms of firm size, to reach several key findings on profits/sales distribution and business growth trends. Here, profits denote net profits. First, detailed balance is observed not only in profits data but also in sales data. Furthermore, the growth-rate distribution of sales has wider tails than the linear growth-rate distribution of profits in log-log scale. On the one hand, in the mid-scale range of profits, the probability of positive growth decreases and the probability of negative growth increases symmetrically as the initial value increases. This is called Non-Gibrat’s First Property. On the other hand, in the mid-scale range of sales, the probability of positive growth decreases as the initial value increases, while the probability of negative growth hardly changes. This is called Non-Gibrat’s Second Property. Under detailed balance, Non-Gibrat’s First and Second Properties are analytically derived from the linear and quadratic growth-rate distributions in log-log scale, respectively. In both cases, the log-normal distribution is inferred from Non-Gibrat’s Properties and detailed balance. These analytic results are verified by empirical data. Consequently, this clarifies the notion that the difference in shapes between growth-rate distributions of sales and profits is closely related to the difference between the two Non-Gibrat’s Properties in the mid-scale range.

Trial type probability modulates the cost of antisaccades

PubMed Central

Chiau, Hui-Yan; Tseng, Philip; Su, Jia-Han; Tzeng, Ovid J. L.; Hung, Daisy L.; Muggleton, Neil G.

2011-01-01

The antisaccade task, where eye movements are made away from a target, has been used to investigate the flexibility of cognitive control of behavior. Antisaccades usually have longer saccade latencies than prosaccades, the so-called antisaccade cost. Recent studies have shown that this antisaccade cost can be modulated by event probability. This may mean that the antisaccade cost can be reduced, or even reversed, if the probability of surrounding events favors the execution of antisaccades. The probabilities of prosaccades and antisaccades were systematically manipulated by changing the proportion of a certain type of trial in an interleaved pro/antisaccades task. We aimed to disentangle the intertwined relationship between trial type probabilities and the antisaccade cost with the ultimate goal of elucidating how probabilities of trial types modulate human flexible behaviors, as well as the characteristics of such modulation effects. To this end, we examined whether implicit trial type probability can influence saccade latencies and also manipulated the difficulty of cue discriminability to see how effects of trial type probability would change when the demand on visual perceptual analysis was high or low. A mixed-effects model was applied to the analysis to dissect the factors contributing to the modulation effects of trial type probabilities. Our results suggest that the trial type probability is one robust determinant of antisaccade cost. These findings highlight the importance of implicit probability in the flexibility of cognitive control of behavior. PMID:21543748

Using serological studies to reconstruct the history of bluetongue epidemic in French cattle under successive vaccination campaigns.

PubMed

Courtejoie, Noémie; Salje, Henrik; Durand, Benoît; Zanella, Gina; Cauchemez, Simon

2018-05-17

Bluetongue virus is a vector-borne pathogen affecting ruminants that has caused major epidemics in France. Reconstructing the history of bluetongue in French cattle under control strategies such as vaccination has been hampered by the high level of sub-clinical infection, incomplete case data and poor understanding of vaccine uptake over time and space. To tackle these challenges, we used three age-structured serological surveys carried out in cattle (N = 22,342) from ten administrative subdivisions called departments. We fitted catalytic models within a Bayesian MCMC framework to reconstruct the force of seroconversion from infection or vaccination, and the population-level susceptibility per semester between 2007 and 2016. In the departments of the study area, we estimated that 36% of cattle had been infected prior to vaccine rollout that became compulsory from July 2008. The last outbreak case was notified in December 2009, at which time 83% of the animals were seropositive, under the cumulative effect of vaccination and infection. The probability of seroconversion per semester dropped below 10% after 2010 when vaccination became optional. Vaccine uptake was smaller during the 2012 campaign than during the one in 2011, with strong regional contrasts. Eighty four percent of cattle were susceptible when bluetongue re-emerged in 2015. Thus, serological surveys can be used to estimate vaccine uptake and the magnitude of infection, the relative effect of which can sometimes be inferred using prior knowledge on reported incidence and vaccination dates. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Paying the piper: the cost of Ca2+ pumping during the mating call of toadfish

PubMed Central

Harwood, Claire L; Young, Iain S; Tikunov, Boris A; Hollingworth, Stephen; Baylor, Stephen M; Rome, Lawrence C

2011-01-01

Abstract Superfast fibres of toadfish swimbladder muscle generate a series of superfast Ca2+ transients, a necessity for high-frequency calling. How is this accomplished with a relatively low rate of Ca2+ pumping by the sarcoplasmic reticulum (SR)? We hypothesized that there may not be complete Ca2+ saturation and desaturation of the troponin Ca2+ regulatory sites with each twitch during calling. To test this, we determined the number of regulatory sites by measuring the concentration of troponin C (TNC) molecules, 33.8 μmol per kg wet weight. We then estimated how much SR Ca2+ is released per twitch by measuring the recovery oxygen consumption in the presence of a crossbridge blocker, N-benzyl-p-toluene sulphonamide (BTS). The results agreed closely with SR release estimates obtained with a kinetic model used to analyse Ca2+ transient measurements. We found that 235 μmol of Ca2+ per kg muscle is released with the first twitch of an 80 Hz stimulus (15oC). Release per twitch declines dramatically thereafter such that by the 10th twitch release is only 48 μmol kg−1 (well below the concentration of TNC Ca2+ regulatory sites, 67.6 μmol kg−1). The ATP usage per twitch by the myosin crossbridges remains essentially constant at ∼25 μmol kg−1 throughout the stimulus period. Hence, for the first twitch, ∼80% of the energy goes into pumping Ca2+ (which uses 1 ATP per 2 Ca2+ ions pumped), but by the 10th and subsequent twitches the proportion is ∼50%. Even though by the 10th stimulus the Ca2+ release per twitch has dropped 5-fold, the Ca2+ remaining in the SR has declined by only ∼18%; hence dwindling SR Ca2+ content is not responsible for the drop. Rather, inactivation of the Ca2+ release channel by myoplasmic Ca2+ likely explains this reduction. If inactivation did not occur, the SR would run out of Ca2+ well before the end of even a 40-twitch call. Hence, inactivation of the Ca2+ release channel plays a critical role in swimbladder muscle during normal in vivo function. PMID:21946852

Comprehensive benchmarking of SNV callers for highly admixed tumor data

PubMed Central

Bohnert, Regina; Vivas, Sonia

2017-01-01

Precision medicine attempts to individualize cancer therapy by matching tumor-specific genetic changes with effective targeted therapies. A crucial first step in this process is the reliable identification of cancer-relevant variants, which is considerably complicated by the impurity and heterogeneity of clinical tumor samples. We compared the impact of admixture of non-cancerous cells and low somatic allele frequencies on the sensitivity and precision of 19 state-of-the-art SNV callers. We studied both whole exome and targeted gene panel data and up to 13 distinct parameter configurations for each tool. We found vast differences among callers. Based on our comprehensive analyses we recommend joint tumor-normal calling with MuTect, EBCall or Strelka for whole exome somatic variant calling, and HaplotypeCaller or FreeBayes for whole exome germline calling. For targeted gene panel data on a single tumor sample, LoFreqStar performed best. We further found that tumor impurity and admixture had a negative impact on precision, and in particular, sensitivity in whole exome experiments. At admixture levels of 60% to 90% sometimes seen in pathological biopsies, sensitivity dropped significantly, even when variants were originally present in the tumor at 100% allele frequency. Sensitivity to low-frequency SNVs improved with targeted panel data, but whole exome data allowed more efficient identification of germline variants. Effective somatic variant calling requires high-quality pathological samples with minimal admixture, a consciously selected sequencing strategy, and the appropriate variant calling tool with settings optimized for the chosen type of data. PMID:29020110

Probability of identifying different salmonella serotypes in poultry samples

USDA-ARS?s Scientific Manuscript database

Recent work has called attention to the unequal competitive abilities of different Salmonella serotypes in standard broth culture and plating media. Such serotypes include Enteritidis and Typhimurium that are specifically targeted in some regulatory and certification programs because they cause a l...

Environmental constraints and call evolution in torrent-dwelling frogs.

PubMed

Goutte, Sandra; Dubois, Alain; Howard, Samuel D; Marquez, Rafael; Rowley, Jodi J L; Dehling, J Maximilian; Grandcolas, Philippe; Rongchuan, Xiong; Legendre, Frédéric

2016-04-01

Although acoustic signals are important for communication in many taxa, signal propagation is affected by environmental properties. Strong environmental constraints should drive call evolution, favoring signals with greater transmission distance and content integrity in a given calling habitat. Yet, few empirical studies have verified this prediction, possibly due to a shortcoming in habitat characterization, which is often too broad. Here we assess the potential impact of environmental constraints on the evolution of advertisement call in four groups of torrent-dwelling frogs in the family Ranidae. We reconstruct the evolution of calling site preferences, both broadly categorized and at a finer scale, onto a phylogenetic tree for 148 species with five markers (∼3600 bp). We test models of evolution for six call traits for 79 species with regard to the reconstructed history of calling site preferences and estimate their ancestral states. We find that in spite of existing morphological constraints, vocalizations of torrent-dwelling species are most probably constrained by the acoustic specificities of torrent habitats and particularly their high level of ambient noise. We also show that a fine-scale characterization of calling sites allows a better perception of the impact of environmental constraints on call evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Real estate ads in Emei music frog vocalizations: female preference for calls emanating from burrows.

PubMed

Cui, Jianguo; Tang, Yezhong; Narins, Peter M

2012-06-23

During female mate choice, both the male's phenotype and resources (e.g. his nest) contribute to the chooser's fitness. Animals other than humans are not known to advertise resource characteristics to potential mates through vocal communication; although in some species of anurans and birds, females do evaluate male qualities through vocal communication. Here, we demonstrate that calls of the male Emei music frog (Babina dauchina), vocalizing from male-built nests, reflect nest structure information that can be recognized by females. Inside-nest calls consisted of notes with energy concentrated at lower frequency ranges and longer note durations when compared with outside-nest calls. Centre frequencies and note durations of the inside calls positively correlate with the area of the burrow entrance and the depth of the burrow, respectively. When given a choice between outside and inside calls played back alternately, more than 70 per cent of the females (33/47) chose inside calls. These results demonstrate that males of this species faithfully advertise whether or not they possess a nest to potential mates by vocal communication, which probably facilitates optimal mate selection by females. These results revealed a novel function of advertisement calls, which is consistent with the wide variation in both call complexity and social behaviour within amphibians.

Multi-species call-broadcast improved detection of endangered Yuma clapper rail compared to single-species call-broadcast

USGS Publications Warehouse

Nadeau, Christopher P.; Conway, Courtney J.; Piest, Linden; Burger, William P.

2013-01-01

Broadcasting calls of marsh birds during point-count surveys increases their detection probability and decreases variation in the number of birds detected across replicate surveys. However, multi-species monitoring using call-broadcast may reduce these benefits if birds are reluctant to call once they hear broadcasted calls of other species. We compared a protocol that uses call-broadcast for only one species (Yuma clapper rail [Rallus longirostris yumanensis]) to a protocol that uses call-broadcast for multiple species. We detected more of each of the following species using the multi-species protocol: 25 % more pied-billed grebes, 160 % more American bitterns, 52 % more least bitterns, 388 % more California black rails, 12 % more Yuma clapper rails, 156 % more Virginia rails, 214 % more soras, and 19 % more common gallinules. Moreover, the coefficient of variation was smaller when using the multi-species protocol: 10 % smaller for pied-billed grebes, 38 % smaller for American bitterns, 19 % smaller for least bitterns, 55 % smaller for California black rails, 5 % smaller for Yuma clapper rails, 38 % smaller for Virginia rails, 44 % smaller for soras, and 8 % smaller for common gallinules. Our results suggest that multi-species monitoring approaches may be more effective and more efficient than single-species approaches even when using call-broadcast.

Characteristics of service requests and service processes of fire and rescue service dispatch centers: analysis of real world data and the underlying probability distributions.

PubMed

Krueger, Ute; Schimmelpfeng, Katja

2013-03-01

A sufficient staffing level in fire and rescue dispatch centers is crucial for saving lives. Therefore, it is important to estimate the expected workload properly. For this purpose, we analyzed whether a dispatch center can be considered as a call center. Current call center publications very often model call arrivals as a non-homogeneous Poisson process. This bases on the underlying assumption of the caller's independent decision to call or not to call. In case of an emergency, however, there are often calls from more than one person reporting the same incident and thus, these calls are not independent. Therefore, this paper focuses on the dependency of calls in a fire and rescue dispatch center. We analyzed and evaluated several distributions in this setting. Results are illustrated using real-world data collected from a typical German dispatch center in Cottbus ("Leitstelle Lausitz"). We identified the Pólya distribution as being superior to the Poisson distribution in describing the call arrival rate and the Weibull distribution to be more suitable than the exponential distribution for interarrival times and service times. However, the commonly used distributions offer acceptable approximations. This is important for estimating a sufficient staffing level in practice using, e.g., the Erlang-C model.

Iterative tailoring of optical quantum states with homodyne measurements.

PubMed

Etesse, Jean; Kanseri, Bhaskar; Tualle-Brouri, Rosa

2014-12-01

As they can travel long distances, free space optical quantum states are good candidates for carrying information in quantum information technology protocols. These states, however, are often complex to produce and require protocols whose success probability drops quickly with an increase of the mean photon number. Here we propose a new protocol for the generation and growth of arbitrary states, based on one by one coherent adjunctions of the simple state superposition α|0〉 + β|1〉. Due to the nature of the protocol, which allows for the use of quantum memories, it can lead to high performances.

Materials separation by dielectrophoresis

NASA Technical Reports Server (NTRS)

Sagar, A. D.; Rose, R. M.

1988-01-01

The feasibility of vacuum dielectrophoresis as a method for particulate materials separation in a microgravity environment was investigated. Particle separations were performed in a specially constructed miniature drop-tower with a residence time of about 0.3 sec. Particle motion in such a system is independent of size and based only on density and dielectric constant, for a given electric field. The observed separations and deflections exceeded the theoretical predictions, probably due to multiparticle effects. In any case, this approach should work well in microgravity for many classes of materials, with relatively simple apparatus and low weight and power requirements.

An empirical analysis of the corporate call decision

NASA Astrophysics Data System (ADS)

Carlson, Murray Dean

1998-12-01

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.

Extended Importance Sampling for Reliability Analysis under Evidence Theory

NASA Astrophysics Data System (ADS)

Yuan, X. K.; Chen, B.; Zhang, B. Q.

2018-05-01

In early engineering practice, the lack of data and information makes uncertainty difficult to deal with. However, evidence theory has been proposed to handle uncertainty with limited information as an alternative way to traditional probability theory. In this contribution, a simulation-based approach, called ‘Extended importance sampling’, is proposed based on evidence theory to handle problems with epistemic uncertainty. The proposed approach stems from the traditional importance sampling for reliability analysis under probability theory, and is developed to handle the problem with epistemic uncertainty. It first introduces a nominal instrumental probability density function (PDF) for every epistemic uncertainty variable, and thus an ‘equivalent’ reliability problem under probability theory is obtained. Then the samples of these variables are generated in a way of importance sampling. Based on these samples, the plausibility and belief (upper and lower bounds of probability) can be estimated. It is more efficient than direct Monte Carlo simulation. Numerical and engineering examples are given to illustrate the efficiency and feasible of the proposed approach.

The Reliability and Stability of an Inferred Phylogenetic Tree from Empirical Data.

PubMed

Katsura, Yukako; Stanley, Craig E; Kumar, Sudhir; Nei, Masatoshi

2017-03-01

The reliability of a phylogenetic tree obtained from empirical data is usually measured by the bootstrap probability (Pb) of interior branches of the tree. If the bootstrap probability is high for most branches, the tree is considered to be reliable. If some interior branches show relatively low bootstrap probabilities, we are not sure that the inferred tree is really reliable. Here, we propose another quantity measuring the reliability of the tree called the stability of a subtree. This quantity refers to the probability of obtaining a subtree (Ps) of an inferred tree obtained. We then show that if the tree is to be reliable, both Pb and Ps must be high. We also show that Ps is given by a bootstrap probability of the subtree with the closest outgroup sequence, and computer program RESTA for computing the Pb and Ps values will be presented. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Anticipating abrupt shifts in temporal evolution of probability of eruption

NASA Astrophysics Data System (ADS)

Rohmer, J.; Loschetter, A.

2016-04-01

Estimating the probability of eruption by jointly accounting for different sources of monitoring parameters over time is a key component for volcano risk management. In the present study, we are interested in the transition from a state of low-to-moderate probability value to a state of high probability value. By using the data of MESIMEX exercise at the Vesuvius volcano, we investigated the potential for time-varying indicators related to the correlation structure or to the variability of the probability time series for detecting in advance this critical transition. We found that changes in the power spectra and in the standard deviation estimated over a rolling time window both present an abrupt increase, which marks the approaching shift. Our numerical experiments revealed that the transition from an eruption probability of 10-15% to > 70% could be identified up to 1-3 h in advance. This additional lead time could be useful to place different key services (e.g., emergency services for vulnerable groups, commandeering additional transportation means, etc.) on a higher level of alert before the actual call for evacuation.

Using hidden Markov models to align multiple sequences.

PubMed

Mount, David W

2009-07-01

A hidden Markov model (HMM) is a probabilistic model of a multiple sequence alignment (msa) of proteins. In the model, each column of symbols in the alignment is represented by a frequency distribution of the symbols (called a "state"), and insertions and deletions are represented by other states. One moves through the model along a particular path from state to state in a Markov chain (i.e., random choice of next move), trying to match a given sequence. The next matching symbol is chosen from each state, recording its probability (frequency) and also the probability of going to that state from a previous one (the transition probability). State and transition probabilities are multiplied to obtain a probability of the given sequence. The hidden nature of the HMM is due to the lack of information about the value of a specific state, which is instead represented by a probability distribution over all possible values. This article discusses the advantages and disadvantages of HMMs in msa and presents algorithms for calculating an HMM and the conditions for producing the best HMM.

Toward a Physical Characterization of Raindrop Collision Outcome Regimes

NASA Technical Reports Server (NTRS)

Testik, F. Y.; Barros, Ana P.; Bilven, Francis L.

2011-01-01

A comprehensive raindrop collision outcome regime diagram that delineates the physical conditions associated with the outcome regimes (i.e., bounce, coalescence, and different breakup types) of binary raindrop collisions is proposed. The proposed diagram builds on a theoretical regime diagram defined in the phase space of collision Weber numbers We and the drop diameter ratio p by including critical angle of impact considerations. In this study, the theoretical regime diagram is first evaluated against a comprehensive dataset for drop collision experiments representative of raindrop collisions in nature. Subsequently, the theoretical regime diagram is modified to explicitly describe the dominant regimes of raindrop interactions in (We, p) by delineating the physical conditions necessary for the occurrence of distinct types of collision-induced breakup (neck/filament, sheet, disk, and crown breakups) based on critical angle of impact consideration. Crown breakup is a subtype of disk breakup for lower collision kinetic energy that presents distinctive morphology. Finally, the experimental results are analyzed in the context of the comprehensive collision regime diagram, and conditional probabilities that can be used in the parameterization of breakup kernels in stochastic models of raindrop dynamics are provided.

GENDER, DEBT, AND DROPPING OUT OF COLLEGE

PubMed Central

DWYER, RACHEL E.; HODSON, RANDY; MCLOUD, LAURA

2012-01-01

For many young Americans, access to credit has become critical to completing a college education and embarking on a successful career path. Young people increasingly face the trade-off of taking on debt to complete college or foregoing college and taking their chances in the labor market without a college degree. These trade-offs are gendered by differences in college preparation and support and by the different labor market opportunities women and men face that affect the value of a college degree and future difficulties they may face in repaying college debt. We examine these new realities by studying gender differences in the role of debt in the pivotal event of graduating from college using the 1997 cohort of the national longitudinal Survey of youth. In this article, we find that women and men both experience slowing and even diminishing probabilities of graduating when carrying high levels of debt, but that men drop out at lower levels of debt than do women. We conclude by theorizing that high levels of debt are one of the mechanisms that sort women and men into different positions in the social stratification system. PMID:23626403

GENDER, DEBT, AND DROPPING OUT OF COLLEGE.

PubMed

Dwyer, Rachel E; Hodson, Randy; McLoud, Laura

2013-02-01

For many young Americans, access to credit has become critical to completing a college education and embarking on a successful career path. Young people increasingly face the trade-off of taking on debt to complete college or foregoing college and taking their chances in the labor market without a college degree. These trade-offs are gendered by differences in college preparation and support and by the different labor market opportunities women and men face that affect the value of a college degree and future difficulties they may face in repaying college debt. We examine these new realities by studying gender differences in the role of debt in the pivotal event of graduating from college using the 1997 cohort of the national longitudinal Survey of youth. In this article, we find that women and men both experience slowing and even diminishing probabilities of graduating when carrying high levels of debt, but that men drop out at lower levels of debt than do women. We conclude by theorizing that high levels of debt are one of the mechanisms that sort women and men into different positions in the social stratification system.

Spontaneous Mass and Charge Losses from Single Multi-Megadalton Ions Studied by Charge Detection Mass Spectrometry

NASA Astrophysics Data System (ADS)

Keifer, David Z.; Alexander, Andrew W.; Jarrold, Martin F.

2017-03-01

Spontaneous mass and charge losses from individual multi-megadalton ions have been observed with charge detection mass spectrometry (CDMS) by trapping single hepatitis B virus (HBV) capsids for 3 s. Gradual increases in the oscillation frequency of single ions in the ion trap are attributed mainly to mass loss (probably solvent, water, and/or salt). The total mass lost during the 3 s trapping period peaks at around 20 kDa for 4 MDa HBV T = 4 capsids. Discrete frequency drops punctuate the gradual increases in the oscillation frequencies. The drops are attributed to a sudden loss of charge. In most cases a single positive charge is lost along with some mass (on average around 1000 Da). Charge loss occurs for over 40% of the trapped ions. It usually occurs near the beginning of the trapping event, and it occurs preferentially in regions of the trap with strong electric fields, indicating that external electric fields promote charge loss. This process may contribute to the decrease in m/ z resolution that often occurs with megadalton ions.

A comparison of survey methods for documenting presence of Myotis leibii (Eastern Small-Footed Bats) at roosting areas in Western Virginia

USGS Publications Warehouse

Huth, John K.; Silvis, Alexander; Moosman, Paul R.; Ford, W. Mark; Sweeten, Sara E.

2015-01-01

Many aspects of foraging and roosting habitat of Myotis leibii (Eastern Small-Footed Bat), an emergent rock roosting-obligate, are poorly described. Previous comparisons of effectiveness of acoustic sampling and mist-net captures have not included Eastern Small-Footed Bat. Habitat requirements of this species differ from congeners in the region, and it is unclear whether survey protocols developed for other species are applicable. Using data from three overlapping studies at two sampling sites in western Virginia’s central Appalachian Mountains, detection probabilities were examined for three survey methods (acoustic surveys with automated identification of calls, visual searches of rock crevices, and mist-netting) for use in the development of “best practices” for future surveys and monitoring. Observer effects were investigated using an expanded version of visual search data. Results suggested that acoustic surveys with automated call identification are not effective for documenting presence of Eastern Small-Footed Bats on talus slopes (basal detection rate of 0%) even when the species is known to be present. The broadband, high frequency echolocation calls emitted by Eastern Small-Footed Bat may be prone to attenuation by virtue of their high frequencies, and these factors, along with signal reflection, lower echolocation rates or possible misidentification to other bat species over talus slopes may all have contributed to poor acoustic survey success. Visual searches and mist-netting of emergent rock had basal detection probabilities of 91% and 75%, respectively. Success of visual searches varied among observers, but detection probability improved with practice. Additionally, visual searches were considerably more economical than mist-netting.

When every drop counts: Analysis of Droughts in Brazil for the 1901-2013 period.

PubMed

Awange, Joseph L; Mpelasoka, Freddie; Goncalves, Rodrigo M

2016-10-01

To provide information useful in policy formulation and management of drought impacts in Brazil, in this study, a sequence of drought events based on monthly rainfall of 1901-2013 on ~25 km x 25 km grid are derived at 4 timescales that include short-timescales (3-month and 6-month) and medium to long-timescales (12-month and 24-month). Subsequently, probability of drought occurrences, intensity, duration and areal-extent are calculated. The probabilities of occurrence of severe and extreme droughts at short-timescales are 1 in 12 and 1 in 66 years, respectively, all over the country. At medium to long-timescales, the probability of severe droughts is about 1 in 20 years in northern Brazil, and 1 in 10 years in the south. The probabilities of extreme droughts are 1 in 9 and 1 in 12 years over northern Brazil and in the south, respectively. In general, no evidence of significant (α =0.05) trend is detected in drought frequency, intensity, and duration over the last 11 decades (since 1901) at all the 4 timescales. The drought areal-extent show increasing trends of 3.4%/decade over Brazil for both 3-month and 6-month timescales. However, the trend increases for the 12-month and 24-month timescales are relatively smaller, i.e., 2.4%/decade and 0.5%/decade, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

The difference between a dynamic and mechanical approach to stroke treatment.

PubMed

Helgason, Cathy M

2007-06-01

The current classification of stroke is based on causation, also called pathogenesis, and relies on binary logic faithful to the Aristotelian tradition. Accordingly, a pathology is or is not the cause of the stroke, is considered independent of others, and is the target for treatment. It is the subject for large double-blind randomized clinical therapeutic trials. The scientific view behind clinical trials is the fundamental concept that information is statistical, and causation is determined by probabilities. Therefore, the cause and effect relation will be determined by probability-theory-based statistics. This is the basis of evidence-based medicine, which calls for the results of such trials to be the basis for physician decisions regarding diagnosis and treatment. However, there are problems with the methodology behind evidence-based medicine. Calculations using probability-theory-based statistics regarding cause and effect are performed within an automatic system where there are known inputs and outputs. This method of research provides a framework of certainty with no surprise elements or outcomes. However, it is not a system or method that will come up with previously unknown variables, concepts, or universal principles; it is not a method that will give a new outcome; and it is not a method that allows for creativity, expertise, or new insight for problem solving.

Simulating the inception of pulsed discharges near positive electrodes

NASA Astrophysics Data System (ADS)

Teunissen, Jannis; Ebert, Ute

2013-09-01

With 3D particle simulations we study the inception of pulsed discharges near positive electrodes. In different geometries, we first determine the breakdown voltage. Then we study the probability of inception for a fast voltage pulse. This probability mostly depends on the availability of seed electrons to generate the initial electron avalanches. These results are compared with experimental observations. Then we investigate how the shape of a starting discharge affects its further development. In particular, we discuss the formation of so-called ``inception clouds.'' JT was supported by STW-project 10755.

Effect of non-linear fluid pressure diffusion on modeling induced seismicity during reservoir stimulation

NASA Astrophysics Data System (ADS)

Gischig, V.; Goertz-Allmann, B. P.; Bachmann, C. E.; Wiemer, S.

2012-04-01

Success of future enhanced geothermal systems relies on an appropriate pre-estimate of seismic risk associated with fluid injection at high pressure. A forward-model based on a semi-stochastic approach was created, which is able to compute synthetic earthquake catalogues. It proved to be able to reproduce characteristics of the seismic cloud detected during the geothermal project in Basel (Switzerland), such as radial dependence of stress drop and b-values as well as higher probability of large magnitude earthquakes (M>3) after shut-in. The modeling strategy relies on a simplistic fluid pressure model used to trigger failure points (so-called seeds) that are randomly distributed around an injection well. The seed points are assigned principal stress magnitudes drawn from Gaussian distributions representative of the ambient stress field. Once the effective stress state at a seed point meets a pre-defined Mohr-Coulomb failure criterion due to a fluid pressure increase a seismic event is induced. We assume a negative linear relationship between b-values and differential stress. Thus, for each event a magnitude can be drawn from a Gutenberg-Richter distribution with a b-value corresponding to differential stress at failure. The result is a seismic cloud evolving in time and space. Triggering of seismic events depends on appropriately calculating the transient fluid pressure field. Hence an effective continuum reservoir model able to reasonably reproduce the hydraulic behavior of the reservoir during stimulation is required. While analytical solutions for pressure diffusion are computationally efficient, they rely on linear pressure diffusion with constant hydraulic parameters, and only consider well head pressure while neglecting fluid injection rate. They cannot be considered appropriate in a stimulation experiment where permeability irreversibly increases by orders of magnitude during injection. We here suggest a numerical continuum model of non-linear pressure diffusion. Permeability increases both reversibly and, if a certain pressure threshold is reached, irreversibly in the form of a smoothed step-function. The models are able to reproduce realistic well head pressure magnitudes for injection rates common during reservoir stimulation. We connect this numerical model with the semi-stochastic seismicity model, and demonstrate the role of non-linear pressure diffusion on earthquakes probability estimates. We further use the model to explore various injection histories to assess the dependence of seismicity on injection strategy. It allows to qualitatively explore the probability of larger magnitude earthquakes (M>3) for different injection volumes, injection times, as well as injection build-up and shut-in strategies.

Modeling Optical and Radiative Properties of Clouds Constrained with CARDEX Observations

NASA Astrophysics Data System (ADS)

Mishra, S. K.; Praveen, P. S.; Ramanathan, V.

2013-12-01

Carbonaceous aerosols (CA) have important effects on climate by directly absorbing solar radiation and indirectly changing cloud properties. These particles tend to be a complex mixture of graphitic carbon and organic compounds. The graphitic component, called as elemental carbon (EC), is characterized by significant absorption of solar radiation. Recent studies showed that organic carbon (OC) aerosols absorb strongly near UV region, and this faction is known as Brown Carbon (BrC). The indirect effect of CA can occur in two ways, first by changing the thermal structure of the atmosphere which further affects dynamical processes governing cloud life cycle; secondly, by acting as cloud condensation nuclei (CCN) that can change cloud radiative properties. In this work, cloud optical properties have been numerically estimated by accounting for CAEDEX (Cloud Aerosol Radiative Forcing Dynamics Experiment) observed cloud parameters and the physico-chemical and optical properties of aerosols. The aerosol inclusions in the cloud drop have been considered as core shell structure with core as EC and shell comprising of ammonium sulfate, ammonium nitrate, sea salt and organic carbon (organic acids, OA and brown carbon, BrC). The EC/OC ratio of the inclusion particles have been constrained based on observations. Moderate and heavy pollution events have been decided based on the aerosol number and BC concentration. Cloud drop's co-albedo at 550nm was found nearly identical for pure EC sphere inclusions and core-shell inclusions with all non-absorbing organics in the shell. However, co-albedo was found to increase for the drop having all BrC in the shell. The co-albedo of a cloud drop was found to be the maximum for all aerosol present as interstitial compare to 50% and 0% inclusions existing as interstitial aerosols. The co-albedo was found to be ~ 9.87e-4 for the drop with 100% inclusions existing as interstitial aerosols externally mixed with micron size mineral dust with 2% hematite content. The cloud spectral optical properties and the radiative properties for the aforesaid cases during CARDEX observations will be discussed in detail.

Experimental verification of hopping mechanism using permanent magnets for an asteroid rover at drop tower

NASA Astrophysics Data System (ADS)

Kurisu, Masamitsu; Yano, Hajime; Yoshimitsu, Tetsuo; Kubota, Takashi; Adachi, Tadashi; Kuroda, Yoji

Verification of the hopping mechanism using permanent magnets by microgravity experiments at ZARM drop tower will be presented in this report. The mechanism, which is called HMPM (Hopping Mechanism with Permanent Magnets) was developed for a small asteroid exploration rover to replace with conventional locomotion mechanism such as wheels and crawlers. The main part of HMPM consists of three permanent magnets which are two stationary magnets and one movable magnet aligned between them. HMPM itself hops by utilizing the impact force generated when the movable magnet sticks to one of the stationary magnets. The features of HMPM are that the large impact force can be generated in spite of low-power consumption, and that it can be easily miniaturized and modularized. On the other hand, the weak point of HMPM is that the performance of the mechanism cannot be controlled directly, since the performance is decided by its design. Therefore, it is significant to evaluate the performance of HMPM before it is mounted on a flight model of rover. On the microgravity experiments at the drop tower, an imitation rover with 0.8kg weight is tested to hop with the operation of a prototype HMPM mounted on the rover. The prototype module weighs only 0.03kg with dimension 0.033 m in width, 0.046 m in height, and 0.012 m in depth, except the drive circuit and power source. Experimental results show the availability of HMPM. Also, the hopping performance of HMPM which is evaluated from the motion of rover recorded by cameras equipped inside the dropping capsule is compared with the estimated performance derived from the theoretical model. From the investigation, validity of the evaluation method based on the theoretical model is discussed. In order that the potential ability of HMPM is fully derived, optimal design of HMPM will require the evaluation method. The experiments at ZARM drop tower were accomplished based on the agreement on the Hayabusa-2 project by DLR-JAXA. And we received technical and operation supports from ZARM. We express our gratitude to ZARM, DLR and JAXA.

Applications of conformal field theory to problems in 2D percolation

NASA Astrophysics Data System (ADS)

Simmons, Jacob Joseph Harris

This thesis explores critical two-dimensional percolation in bounded regions in the continuum limit. The main method which we employ is conformal field theory (CFT). Our specific results follow from the null-vector structure of the c = 0 CFT that applies to critical two-dimensional percolation. We also make use of the duality symmetry obeyed at the percolation point, and the fact that percolation may be understood as the q-state Potts model in the limit q → 1. Our first results describe the correlations between points in the bulk and boundary intervals or points, i.e. the probability that the various points or intervals are in the same percolation cluster. These quantities correspond to order-parameter profiles under the given conditions, or cluster connection probabilities. We consider two specific cases: an anchoring interval, and two anchoring points. We derive results for these and related geometries using the CFT null-vectors for the corresponding boundary condition changing (bcc) operators. In addition, we exhibit several exact relationships between these probabilities. These relations between the various bulk-boundary connection probabilities involve parameters of the CFT called operator product expansion (OPE) coefficients. We then compute several of these OPE coefficients, including those arising in our new probability relations. Beginning with the familiar CFT operator φ1,2, which corresponds to a free-fixed spin boundary change in the q-state Potts model, we then develop physical interpretations of the bcc operators. We argue that, when properly normalized, higher-order bcc operators correspond to successive fusions of multiple φ1,2, operators. Finally, by identifying the derivative of φ1,2 with the operator φ1,4, we derive several new quantities called first crossing densities. These new results are then combined and integrated to obtain the three previously known crossing quantities in a rectangle: the probability of a horizontal crossing cluster, the probability of a cluster crossing both horizontally and vertically, and the expected number of horizontal crossing clusters. These three results were known to be solutions to a certain fifth-order differential equation, but until now no physically meaningful explanation had appeared. This differential equation arises naturally in our derivation.

Outcomes for street children and youth under multidisciplinary care in a drop-in centre in Tegucigalpa, Honduras.

PubMed

Souza, Renato; Porten, Klaudia; Nicholas, Sarala; Grais, Rebecca

2011-11-01

There is little evidence to describe the feasibility and outcomes of services for the care of street children and youth in low-income countries. To describe the outcomes of a multidisciplinary case management approach delivered in a drop-in centre for street children and youth. A longitudinal study of street children and youth followed in an urban drop-in centre. Four hundred (400) street children and youth received a multidisciplinary case management therapeutic package based on the community reinforcement approach. The main outcomes were changes in psychological distress, substance abuse and social situation scores. The median follow-up time for the cohort was 18 months. There were reductions in the levels of psychological distress (p = 0.0001) and substance abuse (p ≤ 0.0001) in the cohort as well as an improvement in the social situation of street children and youth (p = 0.0001). There was a main effect of gender (p < 0.001) and a significant interaction of gender over time (p < 0.001) on improvements in levels of psychological distress. Survival analysis showed that the probability of remaining on substances at 12 months was 0.76 (95% CI: 0.69-0.81) and 0.51 (95% CI: 0.42-0.59) at 24 months. At 12 months, fewer female patients remained using substances compared to male (p < 0.01). To be most effective, programmes and strategies for children and youth in street situations in developing countries should target both their health and social needs.

The spatial distribution of earthquake stress rotations following large subduction zone earthquakes

USGS Publications Warehouse

Hardebeck, Jeanne L.

2017-01-01

Rotations of the principal stress axes due to great subduction zone earthquakes have been used to infer low differential stress and near-complete stress drop. The spatial distribution of coseismic and postseismic stress rotation as a function of depth and along-strike distance is explored for three recent M ≥ 8.8 subduction megathrust earthquakes. In the down-dip direction, the largest coseismic stress rotations are found just above the Moho depth of the overriding plate. This zone has been identified as hosting large patches of large slip in great earthquakes, based on the lack of high-frequency radiated energy. The large continuous slip patches may facilitate near-complete stress drop. There is seismological evidence for high fluid pressures in the subducted slab around the Moho depth of the overriding plate, suggesting low differential stress levels in this zone due to high fluid pressure, also facilitating stress rotations. The coseismic stress rotations have similar along-strike extent as the mainshock rupture. Postseismic stress rotations tend to occur in the same locations as the coseismic stress rotations, probably due to the very low remaining differential stress following the near-complete coseismic stress drop. The spatial complexity of the observed stress changes suggests that an analytical solution for finding the differential stress from the coseismic stress rotation may be overly simplistic, and that modeling of the full spatial distribution of the mainshock static stress changes is necessary.

Adult meerkats modify close call rate in the presence of pups.

PubMed

Wyman, Megan T; Rivers, Pearl R; Muller, Coline; Toni, Pauline; Manser, Marta B

2017-06-01

In animals, signaling behavior is often context-dependent, with variation in the probability of emitting certain signals dependent on fitness advantages. Senders may adjust signaling rate depending on receiver identity, presence of audiences, or noise masking the signal, all of which can affect the benefits and costs of signal production. In the cooperative breeding meerkat Suricata suricatta , group members emit soft contact calls, termed as "close calls", while foraging in order to maintain group cohesion. Here, we investigated how the close calling rate during foraging was affected by the presence of pups, that produce continuous, noisy begging calls as they follow older group members. Adults decreased their overall close call rate substantially when pups were foraging with the group in comparison to periods when no pups were present. We suggest this decrease was likely due to a masking effect of the loud begging calls, which makes the close call function of maintaining group cohesion partly redundant as the centrally located begging calls can be used instead to maintain cohesion. There was some support that adults use close calls strategically to attract specific pups based on fitness advantages, that is, as the philopatric sex, females should call more than males and more to female pups than male pups. Dominant females called more than dominant males when a pup was in close proximity, while subordinates showed no sex-based differences. The sex of the nearest pup did not affect the calling rate of adults. The study shows that meerkats modify their close call production depending on benefits gained from calling and provides an example of the flexible use of one calling system in the presence of another, here contact calls versus begging calls, within the same species.

Bayesian learning

NASA Technical Reports Server (NTRS)

Denning, Peter J.

1989-01-01

In 1983 and 1984, the Infrared Astronomical Satellite (IRAS) detected 5,425 stellar objects and measured their infrared spectra. In 1987 a program called AUTOCLASS used Bayesian inference methods to discover the classes present in these data and determine the most probable class of each object, revealing unknown phenomena in astronomy. AUTOCLASS has rekindled the old debate on the suitability of Bayesian methods, which are computationally intensive, interpret probabilities as plausibility measures rather than frequencies, and appear to depend on a subjective assessment of the probability of a hypothesis before the data were collected. Modern statistical methods have, however, recently been shown to also depend on subjective elements. These debates bring into question the whole tradition of scientific objectivity and offer scientists a new way to take responsibility for their findings and conclusions.

Monte Carlo tests of the ELIPGRID-PC algorithm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davidson, J.R.

1995-04-01

The standard tool for calculating the probability of detecting pockets of contamination called hot spots has been the ELIPGRID computer code of Singer and Wickman. The ELIPGRID-PC program has recently made this algorithm available for an IBM{reg_sign} PC. However, no known independent validation of the ELIPGRID algorithm exists. This document describes a Monte Carlo simulation-based validation of a modified version of the ELIPGRID-PC code. The modified ELIPGRID-PC code is shown to match Monte Carlo-calculated hot-spot detection probabilities to within {plus_minus}0.5% for 319 out of 320 test cases. The one exception, a very thin elliptical hot spot located within a rectangularmore » sampling grid, differed from the Monte Carlo-calculated probability by about 1%. These results provide confidence in the ability of the modified ELIPGRID-PC code to accurately predict hot-spot detection probabilities within an acceptable range of error.« less

X-ray Crystal Truncation Rod Studies of Surface Oxidation and Reduction on Pt(111)

DOE PAGES

Liu, Yihua; Barbour, Andi; Komanicky, Vladimir; ...

2016-02-26

Here, we present X-ray crystal truncation rods measurements of Pt(111) surface under electrochemical conditions. Analyses of crystal truncation rods reveal that surface oxide formation buckles the top surface layer of platinum to two different heights at the potential (0.95 V vs RHE) below the so-called place-exchange potential. While the anti-Bragg intensity, sensitive to the top surface layer, drops in response to the anodic charge transfers, its responses to the cathodic charge transfers are significantly delayed. Implications to the surface oxidation and reduction behaviors are discussed.

FLUSH: A tool for the design of slush hydrogen flow systems

NASA Technical Reports Server (NTRS)

Hardy, Terry L.

1990-01-01

As part of the National Aerospace Plane Project an analytical model was developed to perform calculations for in-line transfer of solid-liquid mixtures of hydrogen. This code, called FLUSH, calculates pressure drop and solid fraction loss for the flow of slush hydrogen through pipe systems. The model solves the steady-state, one-dimensional equation of energy to obtain slush loss estimates. A description of the code is provided as well as a guide for users of the program. Preliminary results are also presented showing the anticipated degradation of slush hydrogen solid content for various piping systems.

Infrared-Proximity-Sensor Modules For Robot

NASA Technical Reports Server (NTRS)

Parton, William; Wegerif, Daniel; Rosinski, Douglas

1995-01-01

Collision-avoidance system for articulated robot manipulators uses infrared proximity sensors grouped together in array of sensor modules. Sensor modules, called "sensorCells," distributed processing board-level products for acquiring data from proximity-sensors strategically mounted on robot manipulators. Each sensorCell self-contained and consists of multiple sensing elements, discrete electronics, microcontroller and communications components. Modules connected to central control computer by redundant serial digital communication subsystem including both serial and a multi-drop bus. Detects objects made of various materials at distance of up to 50 cm. For some materials, such as thermal protection system tiles, detection range reduced to approximately 20 cm.

Microscale Regenerative Heat Exchanger

NASA Technical Reports Server (NTRS)

Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

2006-01-01

The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

Why the water bridge does not collapse

NASA Astrophysics Data System (ADS)

Aerov, Artem A.

2011-09-01

In 2007 an interesting phenomenon was discovered [J. Phys. DJPAPBE0022-372710.1088/0022-3727/40/19/052 40, 6112 (2007)]: a horizontal thread of water, the so-called water bridge, hangs in a horizontal electrostatic field. A different explanation of the water bridge stability is proposed herein: the force supporting it is the surface tension of water, while the role of the electric field is to not allow the water bridge to reduce its surface energy by breaking into separate drops. It is proven that electrostatic field is not the origin of the tension holding the bridge.

Test pilots 1962 - Armstrong, Walker, Dana, Peterson, McKay, Thompson, Butchart

NASA Technical Reports Server (NTRS)

1962-01-01

The research pilots at what in 1962 was called the Flight Research Center standing in front of the X-1E. They are (left to right) Neil Armstrong, Joe Walker, Bill Dana, Bruce Peterson, Jack McKay, Milt Thompson, and Stan Butchart. of the group, Armstrong, Walker, Dana, McKay and Thompson all flew the X-15. Bruce Peterson flew the M2-F2 and HL-10 lifting bodies, while Stan Butchart was the B-29 drop plane pilot for many of the D-558-II and X-1 series research aircraft.

Orientation specific deposition of mesoporous particles

NASA Astrophysics Data System (ADS)

Kjellman, Tomas; Bodén, Niklas; Wennerström, Hâkan; Edler, Karen J.; Alfredsson, Viveka

2014-11-01

We present a protocol for a facile orientation specific deposition of plate-like mesoporous SBA-15 silica particles onto a surface (mesopores oriented normal to surface). A drop of an aqueous dispersion of particles is placed on the surface and water vaporizes under controlled relative humidity. Three requirements are essential for uniform coverage: particle dispersion should not contain aggregates, a weak attraction between particles and surface is needed, and evaporation rate should be low. Aggregates are removed by stirring/sonication. Weak attraction is realized by introducing cationic groups to the surface. Insight into the mechanisms of the so-called coffee stain effect is also provided.

Should the DSM V drop Asperger syndrome?

PubMed

Ghaziuddin, Mohammad

2010-09-01

The DSM IV defines Asperger syndrome (AS) as a pervasive developmental (autistic spectrum) disorder characterized by social deficits and rigid focused interests in the absence of language impairment and cognitive delay. Since its inclusion in the DSM-IV, there has been a dramatic increase in its recognition both in children and adults. However, because studies have generally failed to demonstrate a clear distinction between AS and autism, some researchers have called for its elimination from the forthcoming DSM V. This report argues for a modification of its diagnostic criteria and its continued retention in the diagnostic manual.

Theory of passive proton conductance in lipid bilayers.

PubMed

Nagle, J F

1987-10-01

The large permeability of lipid bilayers to protons compared to other small ions calls for a special proton transport mechanism. At the present time, only mechanisms involving transient hydrogen-bonded chains of water can account for the experimental result that the conductance is nearly independent of pH. Three models involving transient hydrogen-bonded chains are discussed, including an outline of the kinetic calculations that lead to predictions of current versus voltage drop and current versus pH differences. These calculations can be compared to experiment to determine which, if any, of these models pertains to lipid bilayers.

NaOH-based high temperature heat-of-fusion thermal energy storage device

NASA Technical Reports Server (NTRS)

Cohen, B. M.; Rice, R. E.

1978-01-01

A material called Thermkeep, developed as a low-cost method for the storage of thermal energy for solar electric power generating systems is discussed. The storage device consists of an insulated cylinder containing Thermkeep in which coiled tubular heat exchangers are immersed. A one-tenth scale model of the design contains 25 heat-exchanger tubes and 1500 kg of Thermkeep. Its instrumentation includes thermocouples to measure internal Thermkeep temperatures, vessel surface, heated shroud surface, and pressure gauges to indicate heat-exchanger pressure drops. The test-circuit design is presented and experimental results are discussed.

How can history of science matter to scientists?

PubMed

Maienschein, Jane; Laubichler, Manfred; Loettgers, Andrea

2008-06-01

History of science has developed into a methodologically diverse discipline, adding greatly to our understanding of the interplay between science, society, and culture. Along the way, one original impetus for the then newly emerging discipline--what George Sarton called the perspective "from the point of view of the scientist"--dropped out of fashion. This essay shows, by means of several examples, that reclaiming this interaction between science and history of science yields interesting perspectives and new insights for both science and history of science. The authors consequently suggest that historians of science also adopt this perspective as part of their methodological repertoire.

How the bat got its buzz

PubMed Central

Ratcliffe, John M.; Elemans, Coen P. H.; Jakobsen, Lasse; Surlykke, Annemarie

2013-01-01

Since the discovery of echolocation in bats, the final phase of an attack on a flying insect, the ‘terminal buzz’, has proved enigmatic. During the buzz, bats increase information update rates by producing vocalizations up to 220 times s−1. The buzz's ubiquity in hawking and trawling bats implies its importance for hunting success. Superfast muscles, previously unknown in mammals, are responsible for the extreme vocalization rate. Some bats produce a second phase—buzz II—defined by a large drop in the fundamental frequency (F0) of their calls. By doing so, bats broaden their acoustic field of view and should thereby reduce the likelihood of insect escape. We make the case that the buzz was a critical adaptation for capturing night-flying insects, and suggest that the drop in F0 during buzz II requires novel, unidentified laryngeal mechanisms in order to counteract increasing muscle tension. Furthermore, we propose that buzz II represents a countermeasure against the evasive flight of eared prey in the evolutionary arms-race that saw the independent evolution of bat-detecting ears in various groups of night-flying insects. PMID:23302868

Personal genomes in progress: from the human genome project to the personal genome project.

PubMed

Lunshof, Jeantine E; Bobe, Jason; Aach, John; Angrist, Misha; Thakuria, Joseph V; Vorhaus, Daniel B; Hoehe, Margret R; Church, George M

2010-01-01

The cost of a diploid human genome sequence has dropped from about $70M to $2000 since 2007--even as the standards for redundancy have increased from 7x to 40x in order to improve call rates. Coupled with the low return on investment for common single-nucleotide polylmorphisms, this has caused a significant rise in interest in correlating genome sequences with comprehensive environmental and trait data (GET). The cost of electronic health records, imaging, and microbial, immunological, and behavioral data are also dropping quickly. Sharing such integrated GET datasets and their interpretations with a diversity of researchers and research subjects highlights the need for informed-consent models capable of addressing novel privacy and other issues, as well as for flexible data-sharing resources that make materials and data available with minimum restrictions on use. This article examines the Personal Genome Project's effort to develop a GET database as a public genomics resource broadly accessible to both researchers and research participants, while pursuing the highest standards in research ethics.

Unanticipated ankle inversions are significantly different from anticipated ankle inversions during drop landings: overcoming anticipation bias.

PubMed

Dicus, Jeremy R; Seegmiller, Jeff G

2012-05-01

Few ankle inversion studies have taken anticipation bias into account or collected data with an experimental design that mimics actual injury mechanisms. Twenty-three participants performed randomized single-leg vertical drop landings from 20 cm. Subjects were blinded to the landing surface (a flat force plate or 30° inversion wedge on the force plate). After each trial, participants reported whether they anticipated the landing surface. Participant responses were validated with EMG data. The protocol was repeated until four anticipated and four unanticipated landings onto the inversion wedge were recorded. Results revealed a significant main effect for landing condition. Normalized vertical ground reaction force (% body weights), maximum ankle inversion (degrees), inversion velocity (degrees/second), and time from contact to peak muscle activation (seconds) were significantly greater in unanticipated landings, and the time from peak muscle activation to maximum VGRF (second) was shorter. Unanticipated landings presented different muscle activation patterns than landings onto anticipated surfaces, which calls into question the usefulness of clinical studies that have not controlled for anticipation bias.

An activity canyon characterization of the pharmacological topography.

PubMed

Kulkarni, Varsha S; Wild, David J

2016-01-01

Highly chemically similar drugs usually possess similar biological activities, but sometimes, small changes in chemistry can result in a large difference in biological effects. Chemically similar drug pairs that show extreme deviations in activity represent distinctive drug interactions having important implications. These associations between chemical and biological similarity are studied as discontinuities in activity landscapes. Particularly, activity cliffs are quantified by the drop in similar activity of chemically similar drugs. In this paper, we construct a landscape using a large drug-target network and consider the rises in similarity and variation in activity along the chemical space. Detailed analysis of structure and activity gives a rigorous quantification of distinctive pairs and the probability of their occurrence. We analyze pairwise similarity (s) and variation (d) in activity of drugs on proteins. Interactions between drugs are quantified by considering pairwise s and d weights jointly with corresponding chemical similarity (c) weights. Similarity and variation in activity are measured as the number of common and uncommon targets of two drugs respectively. Distinctive interactions occur between drugs having high c and above (below) average d (s). Computation of predicted probability of distinctiveness employs joint probability of c, s and of c, d assuming independence of structure and activity. Predictions conform with the observations at different levels of distinctiveness. Results are validated on the data used and another drug ensemble. In the landscape, while s and d decrease as c increases, d maintains value more than s. c ∈ [0.3, 0.64] is the transitional region where rises in d are significantly greater than drops in s. It is fascinating that distinctive interactions filtered with high d and low s are different in nature. It is crucial that high c interactions are more probable of having above average d than s. Identification of distinctive interactions is better with high d than low s. These interactions belong to diverse classes. d is greatest between drugs and analogs prepared for treatment of same class of ailments but with different therapeutic specifications. In contrast, analogs having low s would treat ailments from distinct classes. Intermittent spikes in d along the axis of c represent canyons in the activity landscape. This new representation accounts for distinctiveness through relative rises in s and d. It provides a mathematical basis for predicting the probability of occurrence of distinctiveness. It identifies the drug pairs at varying levels of distinctiveness and non-distinctiveness. The predicted probability formula is validated even if data approximately satisfy the conditions of its construction. Also, the postulated independence of structure and activity is of little significance to the overall assessment. The difference in distinctive interactions obtained by s and d highlights the importance of studying both of them, and reveals how the choice of measurement can affect the interpretation. The methods in this paper can be used to interpret whether or not drug interactions are distinctive and the probability of their occurrence. Practitioners and researchers can rely on this identification for quantitative modeling and assessment.

Genetics Home Reference: CLN7 disease

MedlinePlus

... unknown. The MFSD8 protein is embedded in the membrane of cell compartments called lysosomes , which digest and recycle different types of molecules. Based on the structure of the protein, MFSD8 probably transports molecules across the lysosomal membrane, but the specific molecules it moves have not ...

Source parameters of microearthquakes on an interplate asperity off Kamaishi, NE Japan over two earthquake cycles

USGS Publications Warehouse

Uchida, Naoki; Matsuzawa, Toru; Ellsworth, William L.; Imanishi, Kazutoshi; Shimamura, Kouhei; Hasegawa, Akira

2012-01-01

We have estimated the source parameters of interplate earthquakes in an earthquake cluster off Kamaishi, NE Japan over two cycles of M~ 4.9 repeating earthquakes. The M~ 4.9 earthquake sequence is composed of nine events that occurred since 1957 which have a strong periodicity (5.5 ± 0.7 yr) and constant size (M4.9 ± 0.2), probably due to stable sliding around the source area (asperity). Using P- and S-wave traveltime differentials estimated from waveform cross-spectra, three M~ 4.9 main shocks and 50 accompanying microearthquakes (M1.5–3.6) from 1995 to 2008 were precisely relocated. The source sizes, stress drops and slip amounts for earthquakes of M2.4 or larger were also estimated from corner frequencies and seismic moments using simultaneous inversion of stacked spectral ratios. Relocation using the double-difference method shows that the slip area of the 2008 M~ 4.9 main shock is co-located with those of the 1995 and 2001 M~ 4.9 main shocks. Four groups of microearthquake clusters are located in and around the mainshock slip areas. Of these, two clusters are located at the deeper and shallower edge of the slip areas and most of these microearthquakes occurred repeatedly in the interseismic period. Two other clusters located near the centre of the mainshock source areas are not as active as the clusters near the edge. The occurrence of these earthquakes is limited to the latter half of the earthquake cycles of the M~ 4.9 main shock. Similar spatial and temporal features of microearthquake occurrence were seen for two other cycles before the 1995 M5.0 and 1990 M5.0 main shocks based on group identification by waveform similarities. Stress drops of microearthquakes are 3–11 MPa and are relatively constant within each group during the two earthquake cycles. The 2001 and 2008 M~ 4.9 earthquakes have larger stress drops of 41 and 27 MPa, respectively. These results show that the stress drop is probably determined by the fault properties and does not change much for earthquakes rupturing in the same area. The occurrence of microearthquakes in the interseismic period suggests the intrusion of aseismic slip, causing a loading of these patches. We also found that some earthquakes near the centre of the mainshock source area occurred just after the earthquakes at the deeper edge of the mainshock source area. These seismic activities probably indicate episodic aseismic slip migrating from the deeper regions in the mainshock asperity to its centre during interseismic periods. Comparison of the source parameters for the 2001 and 2008 main shocks shows that the seismic moments (1.04 x 1016 Nm and 1.12 x 1016 Nm for the 2008 and 2001 earthquakes, respectively) and source sizes (radius = 570 m and 540 m for the 2008 and 2001 earthquakes, respectively) are comparable. Based on careful phase identification and hypocentre relocation by constraining the hypocentres of other small earthquakes to their precisely located centroids, we found that the hypocentres of the 2001 and 2008 M~ 4.9 events are located in the southeastern part of the mainshock source area. This location does not correspond to either episodic slip area or hypocentres of small earthquakes that occurred during the earthquake cycle.

Testing option pricing with the Edgeworth expansion

NASA Astrophysics Data System (ADS)

Balieiro Filho, Ruy Gabriel; Rosenfeld, Rogerio

2004-12-01

There is a well-developed framework, the Black-Scholes theory, for the pricing of contracts based on the future prices of certain assets, called options. This theory assumes that the probability distribution of the returns of the underlying asset is a Gaussian distribution. However, it is observed in the market that this hypothesis is flawed, leading to the introduction of a fudge factor, the so-called volatility smile. Therefore, it would be interesting to explore extensions of the Black-Scholes theory to non-Gaussian distributions. In this paper, we provide an explicit formula for the price of an option when the distributions of the returns of the underlying asset is parametrized by an Edgeworth expansion, which allows for the introduction of higher independent moments of the probability distribution, namely skewness and kurtosis. We test our formula with options in the Brazilian and American markets, showing that the volatility smile can be reduced. We also check whether our approach leads to more efficient hedging strategies of these instruments.

Crash probability estimation via quantifying driver hazard perception.

PubMed

Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang

2018-07-01

Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.

A removal model for estimating detection probabilities from point-count surveys

USGS Publications Warehouse

Farnsworth, G.L.; Pollock, K.H.; Nichols, J.D.; Simons, T.R.; Hines, J.E.; Sauer, J.R.

2000-01-01

We adapted a removal model to estimate detection probability during point count surveys. The model assumes one factor influencing detection during point counts is the singing frequency of birds. This may be true for surveys recording forest songbirds when most detections are by sound. The model requires counts to be divided into several time intervals. We used time intervals of 2, 5, and 10 min to develop a maximum-likelihood estimator for the detectability of birds during such surveys. We applied this technique to data from bird surveys conducted in Great Smoky Mountains National Park. We used model selection criteria to identify whether detection probabilities varied among species, throughout the morning, throughout the season, and among different observers. The overall detection probability for all birds was 75%. We found differences in detection probability among species. Species that sing frequently such as Winter Wren and Acadian Flycatcher had high detection probabilities (about 90%) and species that call infrequently such as Pileated Woodpecker had low detection probability (36%). We also found detection probabilities varied with the time of day for some species (e.g. thrushes) and between observers for other species. This method of estimating detectability during point count surveys offers a promising new approach to using count data to address questions of the bird abundance, density, and population trends.

Economic evaluation of the differential benefits of home visits with telephone calls and telephone calls only in transitional discharge support.

PubMed

Wong, Frances Kam Yuet; So, Ching; Chau, June; Law, Antony Kwan Pui; Tam, Stanley Ku Fu; McGhee, Sarah

2015-01-01

home visits and telephone calls are two often used approaches in transitional care, but their differential economic effects are unknown. to examine the differential economic benefits of home visits with telephone calls and telephone calls only in transitional discharge support. cost-effectiveness analysis conducted alongside a randomised controlled trial (RCT). patients discharged from medical units randomly assigned to control (control, N = 210), home visits with calls (home, N = 196) and calls only (call, N = 204). cost-effectiveness analyses were conducted from the societal perspective comparing monetary benefits and quality-adjusted life years (QALYs) gained. the home arm was less costly but less effective at 28 days and was dominating (less costly and more effective) at 84 days. The call arm was dominating at both 28 and 84 days. The incremental QALY for the home arm was -0.0002/0.0008 (28/84 days), and the call arm was 0.0022/0.0104 (28/84 days). When the three groups were compared, the call arm had a higher probability being cost-effective at 84 days but not at 28 days (home: 53%, call: 35% (28 days) versus home: 22%, call: 73% (84 days)) measuring against the NICE threshold of £20,000. the original RCT showed that the bundled intervention involving home visits and calls was more effective than calls only in the reduction of hospital readmissions. This study adds a cost perspective to inform policymakers that both home visits and calls only are cost-effective for transitional care support, but calls only have a higher chance of being cost-effective for a sustained period after intervention. © The Author 2014. Published by Oxford University Press on behalf of the British Geriatrics Society.

Low frequency baleen whale calls detected on ocean-bottom seismometers in the Lau basin, southwest Pacific Ocean.

PubMed

Brodie, Dana C; Dunn, Robert A

2015-01-01

Ten months of broadband seismic data, recorded on six ocean-bottom seismographs located in the Lau Basin, were examined to identify baleen whale species. As the first systematic survey of baleen whales in this part of the southwest Pacific Ocean, this study reveals the variety of species present and their temporal occurrence in and near the basin. Baleen whales produce species-specific low frequency calls that can be identified by distinct patterns in data spectrograms. By matching spectrograms with published accounts, fin, Bryde's, Antarctic blue, and New Zealand blue whale calls were identified. Probable whale sounds that could not be matched to published spectrograms, as well as non-biologic sounds that are likely of volcanogenic origin, were also recorded. Detections of fin whale calls (mid-June to mid-October) and blue whale calls (June through September) suggest that these species migrate through the region seasonally. Detections of Bryde's whale calls (primarily February to June, but also other times of the year) suggest this species resides around the basin nearly year round. The discovery of previously unpublished call types emphasizes the limited knowledge of the full call repertoires of baleen whales and the utility of using seismic survey data to enhance understanding in understudied regions.

Effect of the human chorionic gonadotropin diet on patient outcomes.

PubMed

Goodbar, Nancy H; Foushee, Jaime A; Eagerton, David H; Haynes, Katie B; Johnson, Amanda A

2013-05-01

To report a case of left lower extremity deep vein thrombosis (DVT) and bilateral pulmonary embolisms in a patient who initiated the human chorionic gonadotropin (HCG) diet 2 weeks prior to presentation. A 64-year-old white female presented with leg swelling and shortness of breath. Lower extremity ultrasound revealed left leg DVT, and a computed tomography angiogram revealed bilateral pulmonary embolisms. A complete history and physical examination were unremarkable for any risk factors for acute thrombosis, with the exception of the initiation of the HCG diet approximately 2 weeks prior to presentation; the patient was taking 20 sublingual drops of HCG twice daily. Results of her hypercoagulable workup were negative. Upon admission, therapy was started with enoxaparin 120 mg subcutaneously twice daily and warfarin 5 mg orally once daily. According to the Naranjo probability scale, initiation of the HCG diet was a probable cause of our patient's adverse effects. The HCG diet has very few efficacy studies and no significant safety studies associated with its use. Six relevant studies were identified for assessment of efficacy, and only 1 was associated with a significant weight reduction in the HCG diet study population. All of these studies evaluated the use of the HCG diet via injections of the hormone and significant calorie restriction, which is known as the Simeons method. Currently marketed HCG products include sublingual drops, lozenges, and pellets, but none of these methods has an evidence-based efficacy and safety standard. As popularity of the HCG diet continues to increase, so do the potential adverse events associated with the management of weight loss via an unproven strategy. Patient safety information regarding this dieting strategy should be recognized by medical professionals.

[Summary of the practice guideline 'The red eye' (first revision) of the Dutch College of General Practitioners (NHG)].

PubMed

van der Weele, G M; Rietveld, R P; Wiersma, Tj; Goudswaard, A N

2007-06-02

The revised NHG-guideline 'The red eye' provides recommendations for the diagnosis and therapy in patients with a red eye. In the presence of pain, decreased visual acuity and photophobia (alarm symptoms) should be considered as sight threatening conditions. In most instances a red eye results from conjunctivitis. The complaint of (an) early morning glued eye(s) makes a bacterial origin of acute infectious conjunctivitis more likely. Itching and a history of infectious conjunctivitis make the probability of bacterial involvement less likely. The type of discharge does not help to adequately distinguish bacterial from viral conjunctivitis. Since an infectious conjunctivitis is a self-limiting condition, no treatment is necessary as a rule. Antibiotic treatment is only rational if conjunctivitis is (most probably) caused by bacteria. It has to be considered only if a patient suffers from much discomfort, if complaints do not begin to decline after 3 days and in patients with preexisting corneal defects. Because of widespread resistance to fusidic acid this should in principle not be prescribed for treatment of conjunctivitis; chloramphenicol is still the drug of choice. During revision of the guideline discussions concentrated on 2 aspects: the position of slit lamp biomicroscopy in general practice and giving a patient with keratoconjunctivitis photoelectrica the remainder of a 'minim' with anaesthetic eye drops. Regarding both topics it was decided not to change the recommendations of the former version of the guideline: the use of slit lamp biomicroscopy remains optional for general practitioners and it remains permitted to give the remainder of a 'minim' with anaesthetic eye drops to a patient with keratoconjunctivitis photoelectrica.

Utilization of extended bayesian networks in decision making under uncertainty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Eeckhout, Edward M; Leishman, Deborah A; Gibson, William L

2009-01-01

Bayesian network tool (called IKE for Integrated Knowledge Engine) has been developed to assess the probability of undesirable events. The tool allows indications and observables from sensors and/or intelligence to feed directly into hypotheses of interest, thus allowing one to quantify the probability and uncertainty of these events resulting from very disparate evidence. For example, the probability that a facility is processing nuclear fuel or assembling a weapon can be assessed by examining the processes required, establishing the observables that should be present, then assembling information from intelligence, sensors and other information sources related to the observables. IKE also hasmore » the capability to determine tasking plans, that is, prioritize which observable should be collected next to most quickly ascertain the 'true' state and drive the probability toward 'zero' or 'one.' This optimization capability is called 'evidence marshaling.' One example to be discussed is a denied facility monitoring situation; there is concern that certain process(es) are being executed at the site (due to some intelligence or other data). We will show how additional pieces of evidence will then ascertain with some degree of certainty the likelihood of this process(es) as each piece of evidence is obtained. This example shows how both intelligence and sensor data can be incorporated into the analysis. A second example involves real-time perimeter security. For this demonstration we used seismic, acoustic, and optical sensors linked back to IKE. We show how these sensors identified and assessed the likelihood of 'intruder' versus friendly vehicles.« less

Pick a Sample.

ERIC Educational Resources Information Center

Peterson, Ivars

1991-01-01

A method that enables people to obtain the benefits of statistics and probability theory without the shortcomings of conventional methods because it is free of mathematical formulas and is easy to understand and use is described. A resampling technique called the "bootstrap" is discussed in terms of application and development. (KR)

Ripple distribution for nonlinear fiber-optic channels.

PubMed

Sorokina, Mariia; Sygletos, Stylianos; Turitsyn, Sergei

2017-02-06

We demonstrate data rates above the threshold imposed by nonlinearity on conventional optical signals by applying novel probability distribution, which we call ripple distribution, adapted to the properties of the fiber channel. Our results offer a new direction for signal coding, modulation and practical nonlinear distortions compensation algorithms.

Calling patterns in human communication dynamics

PubMed Central

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

2013-01-01

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. PMID:23319645

Calling patterns in human communication dynamics.

PubMed

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

2013-01-29

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 c(r)-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.

On the uncertain nature of the core of α Cen A

NASA Astrophysics Data System (ADS)

Bazot, M.; Christensen-Dalsgaard, J.; Gizon, L.; Benomar, O.

2016-08-01

High-quality astrometric, spectroscopic, interferometric and, importantly, asteroseismic observations are available for α Cen A, which is the closest binary star system to earth. Taking all these constraints into account, we study the internal structure of the star by means of theoretical modelling. Using the Aarhus STellar Evolution Code (ASTEC) and the tools of Computational Bayesian Statistics, in particular a Markov chain Monte Carlo algorithm, we perform statistical inferences for the physical characteristics of the star. We find that α Cen A has a probability of approximately 40 per cent of having a convective core. This probability drops to few per cent if one considers reduced rates for the 14N(p,γ)15O reaction. These convective cores have fractional radii less than 8 per cent when overshoot is neglected. Including overshooting also leads to the possibility of a convective core mostly sustained by the ppII chain energy output. We finally show that roughly 30 per cent of the stellar models describing α Cen A are in the subgiant regime.

Capillary Phenomena: Investigations in Compressed Bubble Migration, Geometric Wetting, and Blade-Bound Droplet Stability

NASA Astrophysics Data System (ADS)

Blackmore, William Henry

Capillary flows continue to be important in numerous spacecraft systems where the effective magnitude of the gravity vector is approximately one millionth that of normal Earth gravity. Due to the free fall state of orbiting spacecraft, the effects of capillarity on the fluid systems onboard can dominate the fluid behavior over large length scales. In this research three investigations are pursued where the unique interplay between surface tension forces, wetting characteristics, and system geometry control the fluid behavior, whether in large systems aboard spacecraft, or micro-scale systems on Earth. First, efforts in support of two International Space Station (ISS) experiments are reported. A description of the development of a new NASA ground station at Portland State University is provided along with descriptions of astronaut training activities for the proper operation of four handheld experiments currently in orbit as part of the second iteration of the Capillary Flow Experiments (CFE-2). Concerning the latter, seven more vessels are expected to be launched to the ISS shortly. Analysis of the data alongside numerical simulations shows excellent agreement with theory, and a new intuitive method of viewing critical wetting angles and fluid bulk shift phenomena is offered. Secondly, during the CFE-2 space experiments, unplanned peripheral observations revealed that, on occasion, rapidly compressed air bubbles migrate along paths with vector components common to the residual acceleration onboard the ISS. Unexpectedly however, the migration velocities could be shown to be up to three orders of magnitude greater than the appropriate Stokes flow limit! Likely mechanisms are explored analytically and experimentally while citing prior theoretical works that may have anticipated such phenomena. Once properly understood, compressed bubble migration may be used as an elegant method for phase separation in spacecraft systems or microgravity-based materials manufacturing. Lastly, the stability of drops on surfaces is important in a variety of natural and industrial processes. So called 'wall-edge-vertex bound drops' (a.k.a. drops on blade tips or drops on leaf tips which they resemble) are explored using a numerical approach which applies the Surface Evolver algorithm through implementation of a new file layer and a multi-parameter sweep function. As part of a recently open sourced SE-FIT software, thousands of critical drop configurations are efficiently computed as functions of contact angle, blade edge vertex half-angle, and g-orientation. With the support of other graduate students, simple experiments are performed to benchmark the computations which are then correlated for ease of application. It is shown that sessile, pendant, and wall-edge bound drops are only limiting cases of the more generalized blade-bound drops, and that a ubiquitous 'dry leaf tip' is observed for a range of the critical geometric and wetting parameters.

Elucidating the diet of the island flying fox (Pteropus hypomelanus) in Peninsular Malaysia through Illumina Next-Generation Sequencing.

PubMed

Aziz, Sheema Abdul; Clements, Gopalasamy Reuben; Peng, Lee Yin; Campos-Arceiz, Ahimsa; McConkey, Kim R; Forget, Pierre-Michel; Gan, Han Ming

2017-01-01

There is an urgent need to identify and understand the ecosystem services of pollination and seed dispersal provided by threatened mammals such as flying foxes. The first step towards this is to obtain comprehensive data on their diet. However, the volant and nocturnal nature of bats presents a particularly challenging situation, and conventional microhistological approaches to studying their diet can be laborious and time-consuming, and provide incomplete information. We used Illumina Next-Generation Sequencing (NGS) as a novel, non-invasive method for analysing the diet of the island flying fox ( Pteropus hypomelanus ) on Tioman Island, Peninsular Malaysia. Through DNA metabarcoding of plants in flying fox droppings, using primers targeting the rbcL gene, we identified at least 29 Operationally Taxonomic Units (OTUs) comprising the diet of this giant pteropodid. OTU sequences matched at least four genera and 14 plant families from online reference databases based on a conservative Least Common Ancestor approach, and eight species from our site-specific plant reference collection. NGS was just as successful as conventional microhistological analysis in detecting plant taxa from droppings, but also uncovered six additional plant taxa. The island flying fox's diet appeared to be dominated by figs ( Ficus sp.), which was the most abundant plant taxon detected in the droppings every single month. Our study has shown that NGS can add value to the conventional microhistological approach in identifying food plant species from flying fox droppings. At this point in time, more accurate genus- and species-level identification of OTUs not only requires support from databases with more representative sequences of relevant plant DNA, but probably necessitates in situ collection of plant specimens to create a reference collection. Although this method cannot be used to quantify true abundance or proportion of plant species, nor plant parts consumed, it ultimately provides a very important first step towards identifying plant taxa and spatio-temporal patterns in flying fox diets.

Elucidating the diet of the island flying fox (Pteropus hypomelanus) in Peninsular Malaysia through Illumina Next-Generation Sequencing

PubMed Central

Clements, Gopalasamy Reuben; Peng, Lee Yin; Campos-Arceiz, Ahimsa; McConkey, Kim R.; Forget, Pierre-Michel; Gan, Han Ming

2017-01-01

There is an urgent need to identify and understand the ecosystem services of pollination and seed dispersal provided by threatened mammals such as flying foxes. The first step towards this is to obtain comprehensive data on their diet. However, the volant and nocturnal nature of bats presents a particularly challenging situation, and conventional microhistological approaches to studying their diet can be laborious and time-consuming, and provide incomplete information. We used Illumina Next-Generation Sequencing (NGS) as a novel, non-invasive method for analysing the diet of the island flying fox (Pteropus hypomelanus) on Tioman Island, Peninsular Malaysia. Through DNA metabarcoding of plants in flying fox droppings, using primers targeting the rbcL gene, we identified at least 29 Operationally Taxonomic Units (OTUs) comprising the diet of this giant pteropodid. OTU sequences matched at least four genera and 14 plant families from online reference databases based on a conservative Least Common Ancestor approach, and eight species from our site-specific plant reference collection. NGS was just as successful as conventional microhistological analysis in detecting plant taxa from droppings, but also uncovered six additional plant taxa. The island flying fox’s diet appeared to be dominated by figs (Ficus sp.), which was the most abundant plant taxon detected in the droppings every single month. Our study has shown that NGS can add value to the conventional microhistological approach in identifying food plant species from flying fox droppings. At this point in time, more accurate genus- and species-level identification of OTUs not only requires support from databases with more representative sequences of relevant plant DNA, but probably necessitates in situ collection of plant specimens to create a reference collection. Although this method cannot be used to quantify true abundance or proportion of plant species, nor plant parts consumed, it ultimately provides a very important first step towards identifying plant taxa and spatio-temporal patterns in flying fox diets. PMID:28413729

A Deterministic Annealing Approach to Clustering AIRS Data

NASA Technical Reports Server (NTRS)

Guillaume, Alexandre; Braverman, Amy; Ruzmaikin, Alexander

2012-01-01

We will examine the validity of means and standard deviations as a basis for climate data products. We will explore the conditions under which these two simple statistics are inadequate summaries of the underlying empirical probability distributions by contrasting them with a nonparametric, method called Deterministic Annealing technique

Exploratory Visualization of Graphs Based on Community Structure

ERIC Educational Resources Information Center

Liu, Yujie

2013-01-01

Communities, also called clusters or modules, are groups of nodes which probably share common properties and/or play similar roles within a graph. They widely exist in real networks such as biological, social, and information networks. Allowing users to interactively browse and explore the community structure, which is essential for understanding…

RECRUITING FOR A LONGITUDINAL STUDY OF CHILDREN'S HEALTH USING A HOUSEHOLD-BASED PROBABILITY SAMPLING APPROACH

EPA Science Inventory

The sampling design for the National Children¿s Study (NCS) calls for a population-based, multi-stage, clustered household sampling approach (visit our website for more information on the NCS : www.nationalchildrensstudy.gov). The full sample is designed to be representative of ...

A nonlinear q-voter model with deadlocks on the Watts-Strogatz graph

NASA Astrophysics Data System (ADS)

Sznajd-Weron, Katarzyna; Michal Suszczynski, Karol

2014-07-01

We study the nonlinear $q$-voter model with deadlocks on a Watts-Strogats graph. Using Monte Carlo simulations, we obtain so called exit probability and exit time. We determine how network properties, such as randomness or density of links influence exit properties of a model.

ENVIRONMENTAL MONITORING AND ASSESSMENT PROGRAM (EMAP): WESTERN STREAMS AND RIVERS STATISTICAL SUMMARY

EPA Science Inventory

This statistical summary reports data from the Environmental Monitoring and Assessment Program (EMAP) Western Pilot (EMAP-W). EMAP-W was a sample survey (or probability survey, often simply called 'random') of streams and rivers in 12 states of the western U.S. (Arizona, Californ...

Physics of Incandescent Lamp Burnout

ERIC Educational Resources Information Center

Gluck, Paul; King, John

2008-01-01

Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called "lamps" in what follows) burn out after a lifetime that depends mostly on the temperature…

Individual and Institutional Determinants of Multidimensional Poverty: A European Comparison

ERIC Educational Resources Information Center

Dewilde, Caroline

2008-01-01

In this article we evaluate to what extent between-country differences in the probability of being "multidimensional" poor can be explained by a range of "domain-specific" indicators of welfare regime arrangements. To this end, a so-called micro-macro model is estimated, testing the "independent" effect of…

A Paradigm for the Telephonic Assessment of Suicidal Ideation

ERIC Educational Resources Information Center

Halderman, Brent L.; Eyman, James R.; Kerner, Lisa; Schlacks, Bill

2009-01-01

A three-stage paradigm for telephonically assessing suicidal risk and triaging suicidal callers as practiced in an Employee Assistance Program Call Center was investigated. The first hypothesis was that the use of the procedure would increase the probability that callers would accept the clinician's recommendations, evidenced by fewer police…

Notes on Discounting

ERIC Educational Resources Information Center

Rachlin, Howard

2006-01-01

In general, if a variable can be expressed as a function of its own maximum value, that function may be called a discount function. Delay discounting and probability discounting are commonly studied in psychology, but memory, matching, and economic utility also may be viewed as discounting processes. When they are so viewed, the discount function…

The "Public" University: Recalling Higher Education's Democratic Purpose

ERIC Educational Resources Information Center

Benson, Michael T.; Boyd, Hal R.

2015-01-01

The modern university has been called, "a series of separate schools and departments held together by a central heating system," and, in a play on this line, "a series of individual faculty entrepreneurs held together by a common grievance over parking." Whether parking, heating, or, more probable today, WiFi, these…