High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link
NASA Technical Reports Server (NTRS)
Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli
2016-01-01
We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.
Microprocessor realizations of range rate filters
NASA Technical Reports Server (NTRS)
1979-01-01
The performance of five digital range rate filters is evaluated. A range rate filter receives an input of range data from a radar unit and produces an output of smoothed range data and its estimated derivative range rate. The filters are compared through simulation on an IBM 370. Two of the filter designs are implemented on a 6800 microprocessor-based system. Comparisons are made on the bases of noise variance reduction ratios and convergence times of the filters in response to simulated range signals.
Detecting Signatures of GRACE Sensor Errors in Range-Rate Residuals
NASA Astrophysics Data System (ADS)
Goswami, S.; Flury, J.
2016-12-01
In order to reach the accuracy of the GRACE baseline, predicted earlier from the design simulations, efforts are ongoing since a decade. GRACE error budget is highly dominated by noise from sensors, dealiasing models and modeling errors. GRACE range-rate residuals contain these errors. Thus, their analysis provides an insight to understand the individual contribution to the error budget. Hence, we analyze the range-rate residuals with focus on contribution of sensor errors due to mis-pointing and bad ranging performance in GRACE solutions. For the analysis of pointing errors, we consider two different reprocessed attitude datasets with differences in pointing performance. Then range-rate residuals are computed from these two datasetsrespectively and analysed. We further compare the system noise of four K-and Ka- band frequencies of the two spacecrafts, with range-rate residuals. Strong signatures of mis-pointing errors can be seen in the range-rate residuals. Also, correlation between range frequency noise and range-rate residuals are seen.
Trilateration range and range rate system. Volume 1: CDA system manual
NASA Technical Reports Server (NTRS)
1976-01-01
This document is one of a series of manuals designed to provide the information required to operate and maintain the Command and Data Acquisition (CDA) equipment of the Trilateration Range and Range Rate (TRRR) System. Information pertaining to the equipment in the Trilateration Range and Range Rate System which is designed to interface with existing NASA equipment located at Wallops Island, Virginia is presented.
Influence of tidal range on the stability of coastal marshland
Kirwan, Matthew L.; Guntenspergen, Glenn R.
2010-01-01
Early comparisons between rates of vertical accretion and sea level rise across marshes in different tidal ranges inspired a paradigm that marshes in high tidal range environments are more resilient to sea level rise than marshes in low tidal range environments. We use field-based observations to propose a relationship between vegetation growth and tidal range and to adapt two numerical models of marsh evolution to explicitly consider the effect of tidal range on the response of the marsh platform channel network system to accelerating rates of sea level rise. We find that the stability of both the channel network and vegetated platform increases with increasing tidal range. Our results support earlier hypotheses that suggest enhanced stability can be directly attributable to a vegetation growth range that expands with tidal range. Accretion rates equilibrate to the rate of sea level rise in all experiments regardless of tidal range, suggesting that comparisons between accretion rate and tidal range will not likely produce a significant relationship. Therefore, our model results offer an explanation to widely inconsistent field-based attempts to quantify this relationship while still supporting the long-held paradigm that high tidal range marshes are indeed more stable.
The influence of interspecific interactions on species range expansion rates
Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D.; Schurr, Frank M.; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Dullinger, Stefan; Edwards, Thomas C.; Hickler, Thomas; Higgins, Steven I.; Nabel, Julia E.M.S.; Pagel, Jörn; Normand, Signe
2014-01-01
Ongoing and predicted global change makes understanding and predicting species’ range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low, and if the abundance of one or more strongly interacting species is not closely linked to the abundance of the target species.
The influence of interspecific interactions on species range expansion rates.
Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D; Schurr, Frank M; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H; Dullinger, Stefan; Edwards, Thomas C; Hickler, Thomas; Higgins, Steven I; Nabel, Julia E M S; Pagel, Jörn; Normand, Signe
2014-12-01
Ongoing and predicted global change makes understanding and predicting species' range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low, and if the abundance of one or more strongly interacting species is not closely linked to the abundance of the target species.
The influence of interspecific interactions on species range expansion rates
Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D.; Schurr, Frank M.; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Dullinger, Stefan; Edwards, Thomas C.; Hickler, Thomas; Higgins, Steven I.; Nabel, Julia E. M. S.; Pagel, Jörn; Normand, Signe
2014-01-01
Ongoing and predicted global change makes understanding and predicting species’ range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low, and if the abundance of one or more strongly interacting species is not closely linked to the abundance of the target species. PMID:25722537
Polynomial filter estimation of range and range rate for terminal rendezvous
NASA Technical Reports Server (NTRS)
Philips, R.
1970-01-01
A study was made of a polynomial filter for computing range rate information from CSM VHF range data. The filter's performance during the terminal phase of the rendezvous is discussed. Two modifications of the filter were also made and tested. A manual terminal rendezvous was simulated and desired accuracies were achieved for vehicles on an intercept trajectory, except for short periods following each braking maneuver when the estimated range rate was initially in error by the magnitude of the burn.
NASA Technical Reports Server (NTRS)
Sobel, Edward R.; Oskin, Michael; Burbank, Douglas; Mikolaichuk, Alexander
2005-01-01
The Kyrgyz Range, the northernmost portion of the Kyrgyzstan Tien Shan, displays topographic evidence for lateral propagation of surface uplift and exhumation. The highest and most deeply dissected segment lies in the center of the range. To the east, topography and relief decrease, and preserved remnants of a Cretaceous regional erosion surface imply minimal amounts of bedrock exhumation. The timing of exhumation of range segments defines the lateral propagation rate of the range-bounding reverse fault and quantifies the time and erosion depth needed to transform a mountain range from a juvenile to a mature morphology. New apatite fission-track (AFT) data from three transects from the eastern Kyrgyz Range, combined with published AFT data, demonstrate that the range has propagated over 110 km eastwards over the last 7-11 Myr. Based on the thermal and topographic evolutionary history, we present a model for a time-varying exhumation rate driven by rock uplift and changes in erodability and the time scale of geomorphic adjustment to surface uplift. Easily eroded, Cenozoic sedimentary rocks overlying resistant basement control early, rapid exhumation and slow surface upliftrates. As increasing amounts of resistant basement are exposed, exhumation rates decrease while surface uplift rates are sustained or increase, thereby growing topography. As the range becomes high enough to cause ice accumulation and develop steep river valleys, fluvial and glacial erosion become more powerful and exhumation rates once again increase. Independently determined range-noma1 shortening rates have also varied over time, suggesting a feedback between erosional efficiency and shortening rate.
Hardware test program for evaluation of baseline range/range rate sensor concept
NASA Technical Reports Server (NTRS)
Pernic, E.
1985-01-01
The test program Phase II effort provides additional design information in terms of range and range rate (R/R) sensor performance when observing and tracking a typical spacecraft target. The target used in the test program was a one-third scale model of the Hubble Space Telescope (HST) available at the MSFC test site where the tests were performed. A modified Bendix millimeter wave radar served as the R/R sensor test bed for evaluation of range and range rate tracking performance, and generation of radar signature characteristics of the spacecraft target. A summary of program test results and conclusions are presented along with detailed description of the Bendix test bed radar with accompaning instrumentation. The MSFC test site and facilities are described. The test procedures used to establish background levels, and the calibration procedures used in the range accuracy tests and RCS (radar cross section) signature measurements, are presented and a condensed version of the daily log kept during the 5 September through 17 September test period is also presented. The test program results are given starting with the RCS signature measurements, then continuing with range measurement accuracy test results and finally the range and range rate tracking accuracy test results.
Hardware test program for evaluation of baseline range/range rate sensor concept
NASA Technical Reports Server (NTRS)
1985-01-01
The Hardware Test Program for evaluation of the baseline range/range rate sensor concept was initiated 11 September 1984. This ninth report covers the period 12 May through 11 June 1885. A contract amendment adding a second phase has extended the Hardware Test Program through 10 December 1985. The objective of the added program phase is to establish range and range measurement accuracy and radar signature characteristics for a typical spacecraft target. Phase I of the Hardware Test Program was designed to reduce the risks associated with the Range/Range Rate (R/R) Sensor baseline design approach. These risks are associated with achieving the sensor performance required for the two modes of operation, the Interrupted CW (ICW) mode for initial acquisition and tracking to close-in ranges, and the CW mode, providing coverage during the final docking maneuver. The risks associated with these modes of operation have to do with the realization of adequate sensitivity to operate to their individual maximum ranges.
Video-rate or high-precision: a flexible range imaging camera
NASA Astrophysics Data System (ADS)
Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.; Payne, Andrew D.; Conroy, Richard M.; Godbaz, John P.; Jongenelen, Adrian P. P.
2008-02-01
A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a relatively high resolution (512-by-512) pixels and high precision (0.4 mm best case) configuration, but with a slow measurement rate (one every 10 s). Although this high precision range imaging is useful for some applications, the low acquisition speed is limiting in many situations. The system's frame rate and length of acquisition is fully configurable in software, which means the measurement rate can be increased by compromising precision and image resolution. In this paper we demonstrate the flexibility of our range imaging system by showing examples of high precision ranging at slow acquisition speeds and video-rate ranging with reduced ranging precision and image resolution. We also show that the heterodyne approach and the use of more than four samples per beat cycle provides better linearity than the traditional homodyne quadrature detection approach. Finally, we comment on practical issues of frame rate and beat signal frequency selection.
Long-range dependence and multifractality in the term structure of LIBOR interest rates
NASA Astrophysics Data System (ADS)
Cajueiro, Daniel O.; Tabak, Benjamin M.
2007-01-01
In this paper we present evidence of long-range dependence in LIBOR interest rates. We study a data set from 2000 to 2005, for six different currencies and various maturities. Empirical results suggest that the degree of long-range dependence decreases with maturity, with the exception of interest rates on Japanese Yen and on Indonesian Rupiah. Furthermore, interest rates have a multifractal nature and the degree of multifractality is much stronger for Indonesia (emerging market). These findings suggest that interest rates derivatives should take these features into account. Furthermore, fixed income risk and portfolio management should incorporate long-range dependence in the modeling of interest rates.
A cost/benefit analysis of commercial fusion-fission hybrid reactor development
NASA Astrophysics Data System (ADS)
Kostoff, Ronald N.
1983-04-01
A simple algorithm was developed that allows rapid computation of the ratio, R, of present worth of benefits to present worth of hybrid R&D program costs as a function of potential hybrid unit electricity cost savings, discount rate, electricity demand growth rate, total hybrid R&D program cost, and time to complete a demonstration reactor. In the sensitivity study, these variables were assigned nominal values (unit electricity cost savings of 4 mills/kW-hr, discount rate of 4%/year, growth rate of 2.25%/year, total R&D program cost of 20 billion, and time to complete a demonstration reactor of 30 years), and the variable of interest was varied about its nominal value. Results show that R increases with decreasing discount rate and increasing unit electricity savings and ranges from 4 to 94 as discount rate ranges from 5 to 3%/year and unit electricity savings range from 2 to 6 mills/kW-hr. R increases with increasing growth rate and ranges from 3 to 187 as growth rate ranges from 1 to 3.5%/year and unit electricity cost savings range from 2 to 6 mills/kW-hr. R attains a maximum value when plotted against time to complete a demonstration reactor. The location of this maximum value occurs at shorter completion times as discount rate increases, and this optimal completion time ranges from 20 years for a discount rate of 4%/year to 45 years for a discount rate of 3%/year.
Design and Development of High-Repetition-Rate Satellite Laser Ranging System
NASA Astrophysics Data System (ADS)
Choi, Eun-Jung; Bang, Seong-Cheol; Sung, Ki-Pyoung; Lim, Hyung-Chul; Jung, Chan-Gyu; Kim, In-Yeung; Choi, Jae-Seung
2015-09-01
The Accurate Ranging System for Geodetic Observation ? Mobile (ARGO-M) was successfully developed as the first Korean mobile Satellite Laser Ranging (SLR) system in 2012, and has joined in the International Laser Ranging Service (ILRS) tracking network, DAEdeoK (DAEK) station. The DAEK SLR station was approved as a validated station in April 2014, through the ILRS station ¡°data validation¡± process. The ARGO-M system is designed to enable 2 kHz laser ranging with millimeter-level precision for geodetic, remote sensing, navigation, and experimental satellites equipped with Laser Retroreflector Arrays (LRAs). In this paper, we present the design and development of a next generation high-repetition-rate SLR system for ARGO-M. The laser ranging rate up to 10 kHz is becoming an important issue in the SLR community to improve ranging precision. To implement high-repetition-rate SLR system, the High-repetition-rate SLR operation system (HSLR-10) was designed and developed using ARGO-M Range Gate Generator (A-RGG), so as to enable laser ranging from 50 Hz to 10 kHz. HSLR-10 includes both hardware controlling software and data post-processing software. This paper shows the design and development of key technologies of high-repetition-rate SLR system. The developed system was tested successfully at DAEK station and then moved to Sejong station, a new Korean SLR station, on July 1, 2015. HSLR-10 will begin normal operations at Sejong station in the near future.
Flow Characteristics and Robustness of an Inclined Quad-vortex Range Hood
CHEN, Jia-Kun; HUANG, Rong Fung
2014-01-01
A novel design of range hood, which was termed the inclined quad-vortex (IQV) range hood, was examined for its flow and containment leakage characteristics under the influence of a plate sweeping across the hood face. A flow visualization technique was used to unveil the flow behavior. Three characteristic flow modes were observed: convex, straight, and concave modes. A tracer gas detection method using sulfur hexafluoride (SF6) was employed to measure the containment leakage levels. The results were compared with the test data reported previously in the literature for a conventional range hood and an inclined air curtain (IAC) range hood. The leakage SF6 concentration of the IQV range hood under the influence of the plate sweeping was 0.039 ppm at a suction flow rate of 9.4 m3/min. The leakage concentration of the conventional range hood was 0.768 ppm at a suction flow rate of 15.0 m3/min. For the IAC range hood, the leakage concentration was 0.326 ppm at a suction flow rate of 10.9 m3/min. The IQV range hood presented a significantly lower leakage level at a smaller suction flow rate than the conventional and IAC range hoods due to its aerodynamic design for flow behavior. PMID:24583513
Figueira, Rita de Cássia Sávio; Setti, Amanda S; Braga, Daniela P A F; Iaconelli, Assumpto; Borges, Edson
2014-08-01
To determine whether Brazilian egg donation treatment outcomes with oocytes donated from infertile couples are equivalent to those obtained worldwide with oocytes donated from fertile egg-donors. In this descriptive study, egg-donation cycles from 259 women, performed from January 2009 to July 2013, were evaluated. Oocytes were obtained from patients undergoing ICSI who decided to donate their surplus oocytes. We described the survival, fertilization, blastocyst, implantation and pregnancy rates obtained in our infertile donor-recipient program. In addition, we described the results obtained in previous published studies. In our egg-donation program we obtained a fertilization rate of 72.9 %, a blastocyst formation rate of 53.2 %, an implantation rate of 31.1 % and the estimated clinical pregnancy rate per warmed oocyte was 5.4 %. The analyzed studies, performed between 2008 and 2013, included varying numbers of egg-donors (range: 20-600), warmed oocytes (range: 123-3826) and survival rates (range: 85.6-92.5 %). Fertilization rates ranged from 74.2 to 87.0 %, blastocyst formation rate ranged from 41.3 % to 68.0 %, implantation rates ranged from 24.7 % to 55.3 % and the clinical pregnancy rate per warmed oocyte ranged from 3.9 % to 9.8 %. New and reassuring information derived from our egg-donation program demonstrates outcomes similar to those reported for other egg donation programs.
Ranging and tracking system for proximity operations, phase 1
NASA Technical Reports Server (NTRS)
Udalov, S.; Nilsen, P. W.
1979-01-01
A study task is reported which is directed towards developing a conceptual design of a small, lightweight range and range rate radar sensor system to meet NASA's requirements for accurate short-range and velocity measurements in an orbital environment. Within the context of the requirements, the short range implies system operation at 0 m to 1850 m (6000 ft) and accurate implies a range measurement to within 1 sigma accuracy of 0.20 m (0.67 ft) and a range rate (velocity) measurement to within 1 sigma accuracy of 0.01 m/sec (0.033 ft/sec).
Are Plant Species Able to Keep Pace with the Rapidly Changing Climate?
Cunze, Sarah; Heydel, Felix; Tackenberg, Oliver
2013-01-01
Future climate change is predicted to advance faster than the postglacial warming. Migration may therefore become a key driver for future development of biodiversity and ecosystem functioning. For 140 European plant species we computed past range shifts since the last glacial maximum and future range shifts for a variety of Intergovernmental Panel on Climate Change (IPCC) scenarios and global circulation models (GCMs). Range shift rates were estimated by means of species distribution modelling (SDM). With process-based seed dispersal models we estimated species-specific migration rates for 27 dispersal modes addressing dispersal by wind (anemochory) for different wind conditions, as well as dispersal by mammals (dispersal on animal's coat – epizoochory and dispersal by animals after feeding and digestion – endozoochory) considering different animal species. Our process-based modelled migration rates generally exceeded the postglacial range shift rates indicating that the process-based models we used are capable of predicting migration rates that are in accordance with realized past migration. For most of the considered species, the modelled migration rates were considerably lower than the expected future climate change induced range shift rates. This implies that most plant species will not entirely be able to follow future climate-change-induced range shifts due to dispersal limitation. Animals with large day- and home-ranges are highly important for achieving high migration rates for many plant species, whereas anemochory is relevant for only few species. PMID:23894290
Shi, Xin; Yang, Zhiping; Wu, Qiong; Fan, Daiming
2017-01-01
Background Evidence regarding the benefit of therapy to prevent the post-polypectomy recurrence of colorectal adenoma is limited. Endoscopic recurrence is the main outcome according to an evaluation of trials involving recurrence prevention. Aim To estimate the recurrence rates of post-polypectomy colorectal adenoma in placebo-controlled arms of randomized clinical trials and to identify the prognostic factors influencing these rates. Methods We combined data from all randomized controlled trials evaluating therapies for colorectal adenoma using placebo from 1988 to 2016. The data were combined in a random-effects model. Primary outcomes were endoscopic adenoma and advanced adenoma recurrence of colorectal adenoma. Results The pooled estimates of the adenoma recurrence rates were 37% (95% confidence interval [CI], 33%-41%; range, 33%-52%) at 1 year, 47% (95% CI, 41%-54%; range, 46%-51%) at 2 years, 41% (95% CI, 33%-48%; range, 20%-61%) at 3 years, 48% (95% CI, 38%-57%; range, 37%-53%) at 4 years, and 60% (95% CI, 52%-68%; range, 48%-68%) at 5 years. The pooled estimates of the advanced adenoma recurrence rates were 10% (95% CI, 6%-15%; range, 7%-13%) at 1 year, 12% (95% CI, 8%-16%; range, 3%-19%) at 3 years, 14% (95% CI, 10%-18%; range, 13%-16%) at 4 years, and 14% (95% CI, 10%-19%; range, 9%-21%) at 5 years. Significant heterogeneity among the randomized clinical trials (P < 0.001) was observed for each recurrence rate. Conclusions This meta-analysis confirms the heterogeneity of recurrence rates among post-polypectomy colorectal adenoma patients who received placebo. No single design variable was identified that might explain the heterogeneity. PMID:28977952
NASA Technical Reports Server (NTRS)
Georgevic, R. M.
1973-01-01
Closed-form analytic expressions for the time variations of instantaneous orbital parameters and of the topocentric range and range rate of a spacecraft moving in the gravitational field of an oblate large body are derived using a first-order variation of parameters technique. In addition, the closed-form analytic expressions for the partial derivatives of the topocentric range and range rate are obtained, with respect to the coefficient of the second harmonic of the potential of the central body (J sub 2). The results are applied to the motion of a point-mass spacecraft moving in the orbit around the equatorially elliptic, oblate sun, with J sub 2 approximately equal to .000027.
NASA Technical Reports Server (NTRS)
Lund, G. F.; Westbrook, R. M.; Fryer, T. B.
1980-01-01
The design details and rationale for a versatile, long-range, long-life telemetry data acquisition system for heart rates and body temperatures at multiple locations from free-ranging animals are presented. The design comprises an implantable transmitter for short to medium range transmission, a receiver retransmitter collar to be worn for long-range transmission, and a signal conditioner interface circuit to assist in signal discrimination and demodulation of receiver or tape-recorded audio outputs. Implanted electrodes are used to obtain an ECG, from which R-wave characteristics are selected to trigger a short RF pulse. Pulses carrying heart rate information are interrupted periodically by a series of pulse interval modulated RF pulses conveying temperature information sensed at desired locations by thermistors. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as radio frequency interference. The implanted transmitter may be used alone for medium and short-range tracking, or with a receiver-transmitter collar that employs commercial tracking equipment for transmissions of up to 12 km. A system prototype has been tested on a dog.
Preliminary orbit determination for lunar satellites.
NASA Technical Reports Server (NTRS)
Lancaster, E. R.
1973-01-01
Methods for the determination of orbits of artificial lunar satellites from earth-based range rate measurements developed by Koskela (1964) and Bateman et al. (1966) are simplified and extended to include range measurements along with range rate measurements. For illustration, a numerical example is presented.
Poultry abattoir survey of carcass condemnation for standard, vegetarian, and free range chickens.
Herenda, D; Jakel, O
1994-05-01
During the period April 1991 to March 1992, data concerning the condemnation rate of standard, vegetarian, and free-range chickens were collected and summarized from one federally inspected abattoir in Ontario. The purpose of this study was to discuss the effects of diet, management, and breed of chickens on pathological lesions, ensuing condemnation rates, and consequent losses to the growers and the poultry industry. The data collected at this abattoir revealed that vegetarian chickens showed a higher condemnation rate (5.23%) for disease and nondisease conditions compared with standard (1.48%) and free-range (0.94%) chickens. Free-range chickens were approximately two weeks older than vegetarian and standard chickens at the time of slaughter. The most common causes of condemnation in vegetarian chickens was cellulitis (1.18%), followed by ascites (0.77%). Ascites and cellulitis (0.26% both) were also the most common causes of condemnation in standard chickens. Cyanosis (0.21%) and mutilation (0.17%) represented the highest rate of condemnation in free-range chickens. The low rate of pathological lesions in free-range chickens is a positive trend in poultry disease management.
NASA Technical Reports Server (NTRS)
Britt, C. L., Jr.
1975-01-01
The development of an RF Multilateration system to provide accurate position and velocity measurements during the approach and landing phase of Vertical Takeoff Aircraft operation is discussed. The system uses an angle-modulated ranging signal to provide both range and range rate measurements between an aircraft transponder and multiple ground stations. Range and range rate measurements are converted to coordinate measurements and the coordinate and coordinate rate information is transmitted by an integral data link to the aircraft. Data processing techniques are analyzed to show advantages and disadvantages. Error analyses are provided to permit a comparison of the various techniques.
Using demography and movement behavior to predict range expansion of the southern sea otter.
Tinker, M.T.; Doak, D.F.; Estes, J.A.
2008-01-01
In addition to forecasting population growth, basic demographic data combined with movement data provide a means for predicting rates of range expansion. Quantitative models of range expansion have rarely been applied to large vertebrates, although such tools could be useful for restoration and management of many threatened but recovering populations. Using the southern sea otter (Enhydra lutris nereis) as a case study, we utilized integro-difference equations in combination with a stage-structured projection matrix that incorporated spatial variation in dispersal and demography to make forecasts of population recovery and range recolonization. In addition to these basic predictions, we emphasize how to make these modeling predictions useful in a management context through the inclusion of parameter uncertainty and sensitivity analysis. Our models resulted in hind-cast (1989–2003) predictions of net population growth and range expansion that closely matched observed patterns. We next made projections of future range expansion and population growth, incorporating uncertainty in all model parameters, and explored the sensitivity of model predictions to variation in spatially explicit survival and dispersal rates. The predicted rate of southward range expansion (median = 5.2 km/yr) was sensitive to both dispersal and survival rates; elasticity analysis indicated that changes in adult survival would have the greatest potential effect on the rate of range expansion, while perturbation analysis showed that variation in subadult dispersal contributed most to variance in model predictions. Variation in survival and dispersal of females at the south end of the range contributed most of the variance in predicted southward range expansion. Our approach provides guidance for the acquisition of further data and a means of forecasting the consequence of specific management actions. Similar methods could aid in the management of other recovering populations.
Knies, Jennifer L.; Kingsolver, Joel G.
2013-01-01
The initial rise of fitness that occurs with increasing temperature is attributed to Arrhenius kinetics, in which rates of reaction increase exponentially with increasing temperature. Models based on Arrhenius typically assume single rate-limiting reaction(s) over some physiological temperature range for which all the rate-limiting enzymes are in 100% active conformation. We test this assumption using datasets for microbes that have measurements of fitness (intrinsic rate of population growth) at many temperatures and over a broad temperature range, and for diverse ectotherms that have measurements at fewer temperatures. When measurements are available at many temperatures, strictly Arrhenius kinetics is rejected over the physiological temperature range. However, over a narrower temperature range, we cannot reject strictly Arrhenius kinetics. The temperature range also affects estimates of the temperature dependence of fitness. These results indicate that Arrhenius kinetics only apply over a narrow range of temperatures for ectotherms, complicating attempts to identify general patterns of temperature dependence. PMID:20528477
Knies, Jennifer L; Kingsolver, Joel G
2010-08-01
The initial rise of fitness that occurs with increasing temperature is attributed to Arrhenius kinetics, in which rates of reaction increase exponentially with increasing temperature. Models based on Arrhenius typically assume single rate-limiting reactions over some physiological temperature range for which all the rate-limiting enzymes are in 100% active conformation. We test this assumption using data sets for microbes that have measurements of fitness (intrinsic rate of population growth) at many temperatures and over a broad temperature range and for diverse ectotherms that have measurements at fewer temperatures. When measurements are available at many temperatures, strictly Arrhenius kinetics are rejected over the physiological temperature range. However, over a narrower temperature range, we cannot reject strictly Arrhenius kinetics. The temperature range also affects estimates of the temperature dependence of fitness. These results indicate that Arrhenius kinetics only apply over a narrow range of temperatures for ectotherms, complicating attempts to identify general patterns of temperature dependence.
Local extinction and turnover rates at the edge and interior of species' ranges
Doherty, P.F.; Boulinier, T.; James., D.
2003-01-01
One hypothesis for the maintenance of the edge of a species' range suggests that more central (and abundant) populations are relatively stable and edge populations are less stable with increased local extinction and turnover rates. To date, estimates of such metrics are equivocal due to design and analysis flaws. Apparent increased estimates of extinction and turnover rates at the edge of range, versus the interior, could be a function of decreased detection probabilities alone, and not of a biological process. We estimated extinction and turnover rates for species at the interiors and edges of their ranges using an approach which incorporates potential heterogeneity in species detection probabilities. Extinction rates were higher at the edges (0.17 ?? 0.03 []) than in the interiors (0.04 ?? 0.01), as was turnover. Without taking the probability of detection into account these differences would be artificially magnified. Knowledge of extinction and turnover rates is essential in furthering our understanding of range dynamics, and in directing conservation efforts. This study further illustrates the practical application of methods proposed recently for estimating extinction rates and other community dynamic parameters.
Local extinction and turnover rates at the edge and interior of species' ranges
Doherty, P.F.; Boulinier, T.; Nichols, J.D.
2003-01-01
One hypothesis for the maintenance of the edge of a species' range suggests that more central (and abundant) populations are relatively stable and edge populations are less stable with increased local extinction and turnover rates. To date, estimates of such metrics are equivocal due to design and analysis flaws. Apparent increased estimates of extinction and turnover rates at the edge of range, versus the interior, could be a function of decreased detection probabilities alone, and not of a biological process. We estimated extinction and turnover rates for species at the interiors and edges of their ranges using an approach which incorporates potential heterogeneity in species detection probabilities. Extinction rates were higher at the edges (0.17 ' 0.03 [SE]) than in the interiors (0.04 ' 0.01), as was turnover. Without taking the probability of detection into account these differences would be artificially magnified. Knowledge of extinction and turnover rates is essential in furthering our understanding of range dynamics, and in directing conservation efforts. This study further illustrates the practical application of methods proposed recently for estimating extinction rates and other community dynamic parameters.
Performance goals on simulators boost resident motivation and skills laboratory attendance.
Stefanidis, Dimitrios; Acker, Christina E; Greene, Frederick L
2010-01-01
To assess the impact of setting simulator training goals on resident motivation and skills laboratory attendance. Residents followed a proficiency-based laparoscopic curriculum on the 5 Fundamentals of Laparoscopic Surgery and 9 virtual reality tasks. Training goals consisted of the average expert performance on each task + 2 SD (mandatory) and best expert performance (optional). Residents rated the impact of the training goals on their motivation on a 20-point visual analog scale. Performance and attendance data were analyzed and correlated (Spearman's). Data are reported as medians (range). General Surgery residency program at a regional referral Academic Medical Center. General surgery residents (n = 15). During the first 5 months of the curriculum, weekly attendance rate was 51% (range, 8-96). After 153 (range, 21-412) repetitions, resident speed improved by 97% (range, 18-230), errors improved by 17% (range, 0-24), and motion efficiency by 59% (range, 26-114) compared with their baseline. Nine (60%) residents achieved proficiency in 7 (range, 3-14) and the best goals in 3.5 (range, 1-9) tasks; the other 6 residents had attendance rates <30%. Residents rated the impact of setting performance goals on their motivation as 15 (range, 1-18) and setting a best goal as 13 (range, 1-18). Motivation ratings correlated positively with attendance rates, number of repetitions, performance improvement, and achievement of proficiency and best goals (r = 0.59-0.75; p < 0.05) but negatively with postgraduate year (PGY) (-0.67; p = 0.02). Setting training goals on simulators are associated with improved resident motivation to participate in a simulator curriculum. While more stringent goals may potentiate this effect, they have a limited impact on senior residents. Further research is needed to investigate ways to improve skills laboratory attendance. Copyright 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Evolved dispersal strategies at range margins
Dytham, Calvin
2009-01-01
Dispersal is a key component of a species's ecology and will be under different selection pressures in different parts of the range. For example, a long-distance dispersal strategy suitable for continuous habitat at the range core might not be favoured at the margin, where the habitat is sparse. Using a spatially explicit, individual-based, evolutionary simulation model, the dispersal strategies of an organism that has only one dispersal event in its lifetime, such as a plant or sessile animal, are considered. Within the model, removing habitat, increasing habitat turnover, increasing the cost of dispersal, reducing habitat quality or altering vital rates imposes range limits. In most cases, there is a clear change in the dispersal strategies across the range, although increasing death rate towards the margin has little impact on evolved dispersal strategy across the range. Habitat turnover, reduced birth rate and reduced habitat quality all increase evolved dispersal distances at the margin, while increased cost of dispersal and reduced habitat density lead to lower evolved dispersal distances at the margins. As climate change shifts suitable habitat poleward, species ranges will also start to shift, and it will be the dispersal capabilities of marginal populations, rather than core populations, that will influence the rate of range shifting. PMID:19324810
Analysis of ionospheric refraction error corrections for GRARR systems
NASA Technical Reports Server (NTRS)
Mallinckrodt, A. J.; Parker, H. C.; Berbert, J. H.
1971-01-01
A determination is presented of the ionospheric refraction correction requirements for the Goddard range and range rate (GRARR) S-band, modified S-band, very high frequency (VHF), and modified VHF systems. The relation ships within these four systems are analyzed to show that the refraction corrections are the same for all four systems and to clarify the group and phase nature of these corrections. The analysis is simplified by recognizing that the range rate is equivalent to a carrier phase range change measurement. The equation for the range errors are given.
5 CFR 530.323 - Setting pay when a special rate is discontinued or decreased.
Code of Federal Regulations, 2011 CFR
2011-01-01
... of a rate range within a schedule); or (2) The reduction in the scope of coverage of the special rate... retention under 5 CFR part 536, the employee's rate of pay is set in the highest applicable rate range at...
Xue, Li; Li, Zhulian; Zhang, Labao; Zhai, Dongsheng; Li, Yuqiang; Zhang, Sen; Li, Ming; Kang, Lin; Chen, Jian; Wu, Peiheng; Xiong, Yaoheng
2016-08-15
Satellite laser ranging operating at 1064 nm wavelength using superconducting nanowire single-photon detectors (SNSPDs) is successfully demonstrated. A SNSPD with an intrinsic quantum efficiency of 80% and a dark count rate of 100 cps at 1064 nm wavelength is developed and introduced to Yunnan Observatory in China. With improved closed-loop telescope systems (field of view of about 26''), satellites including Cryosat, Ajisai, and Glonass with ranges of 1600 km, 3100 km, and 19,500 km, respectively, are experimentally ranged with mean echo rates of 1200/min, 4200/min, and 320/min, respectively. To the best of our knowledge, this is the first demonstration of laser ranging for satellites using SNSPDs at 1064 nm wavelength. Theoretical analysis of the detection efficiency and the mean echo rate for typical satellites indicate that it is possible for a SNSPD to range satellites from low Earth orbit to geostationary Earth orbit.
Poultry abattoir survey of carcass condemnation for standard, vegetarian, and free range chickens.
Herenda, D; Jakel, O
1994-01-01
During the period April 1991 to March 1992, data concerning the condemnation rate of standard, vegetarian, and free-range chickens were collected and summarized from one federally inspected abattoir in Ontario. The purpose of this study was to discuss the effects of diet, management, and breed of chickens on pathological lesions, ensuing condemnation rates, and consequent losses to the growers and the poultry industry. The data collected at this abattoir revealed that vegetarian chickens showed a higher condemnation rate (5.23%) for disease and nondisease conditions compared with standard (1.48%) and free-range (0.94%) chickens. Free-range chickens were approximately two weeks older than vegetarian and standard chickens at the time of slaughter. The most common causes of condemnation in vegetarian chickens was cellulitis (1.18%), followed by ascites (0.77%). Ascites and cellulitis (0.26% both) were also the most common causes of condemnation in standard chickens. Cyanosis (0.21%) and mutilation (0.17%) represented the highest rate of condemnation in free-range chickens. The low rate of pathological lesions in free-range chickens is a positive trend in poultry disease management. PMID:8050075
Trajectory control sensor engineering model detailed test objective
NASA Technical Reports Server (NTRS)
Dekome, Kent; Barr, Joseph Martin
1991-01-01
The concept employed in an existing Trajectory Control Sensor (TCS) breadboard is being developed into an engineering model to be considered for flight on the Shuttle as a Detailed Test Objective (DTO). The sensor design addresses the needs of Shuttle/SSF docking/berthing by providing relative range and range rate to 1500 meters as well as the perceived needs of AR&C by relative attitude measurement over the last 100 meters. Range measurement is determined using a four-tone ranging technique. The Doppler shift on the highest frequency tone will be used to provide direct measurement of range rate. Bearing rate and attitude rates will be determined through back differencing of bearing and attitude, respectively. The target consists of an isosceles triangle configuration of three optical retroreflectors, roughly one meter and one-half meter in size. After target acquisition, the sensor continually updates the positions of the three retros at a rate of about one hertz. The engineering model is expected to weigh about 25 pounds, consume 25-30 watts, and have an envelope of about 1.25 cubic feet. The following concerns were addressed during the presentation: are there any concerns with differentiating attitude and bearing to get attitude and bearing rates? Since the docking scenario has low data bandwidth, back differencing is a sufficient approximation of a perfect differentiator for this application. Could range data be obtained if there were no retroreflectors on the target vehicle? Possibly, but only at close range. It would be dependent on target characteristics.
Lifespan of mountain ranges scaled by feedbacks between landsliding and erosion by rivers.
Egholm, David L; Knudsen, Mads F; Sandiford, Mike
2013-06-27
An important challenge in geomorphology is the reconciliation of the high fluvial incision rates observed in tectonically active mountain ranges with the long-term preservation of significant mountain-range relief in ancient, tectonically inactive orogenic belts. River bedrock erosion and sediment transport are widely recognized to be the principal controls on the lifespan of mountain ranges. But the factors controlling the rate of erosion and the reasons why they seem to vary significantly as a function of tectonic activity remain controversial. Here we use computational simulations to show that the key to understanding variations in the rate of erosion between tectonically active and inactive mountain ranges may relate to a bidirectional coupling between bedrock river incision and landslides. Whereas fluvial incision steepens surrounding hillslopes and increases landslide frequency, landsliding affects fluvial erosion rates in two fundamentally distinct ways. On the one hand, large landslides overwhelm the river transport capacity and cause upstream build up of sediment that protects the river bed from further erosion. On the other hand, in delivering abrasive agents to the streams, landslides help accelerate fluvial erosion. Our models illustrate how this coupling has fundamentally different implications for rates of fluvial incision in active and inactive mountain ranges. The coupling therefore provides a plausible physical explanation for the preservation of significant mountain-range relief in old orogenic belts, up to several hundred million years after tectonic activity has effectively ceased.
The shape and temporal dynamics of phylogenetic trees arising from geographic speciation.
Pigot, Alex L; Phillimore, Albert B; Owens, Ian P F; Orme, C David L
2010-12-01
Phylogenetic trees often depart from the expectations of stochastic models, exhibiting imbalance in diversification among lineages and slowdowns in the rate of lineage accumulation through time. Such departures have led to a widespread perception that ecological differences among species or adaptation and subsequent niche filling are required to explain patterns of diversification. However, a key element missing from models of diversification is the geographical context of speciation and extinction. In this study, we develop a spatially explicit model of geographic range evolution and cladogenesis, where speciation arises via vicariance or peripatry, and explore the effects of these processes on patterns of diversification. We compare the results with those observed in 41 reconstructed avian trees. Our model shows that nonconstant rates of speciation and extinction are emergent properties of the apportioning of geographic ranges that accompanies speciation. The dynamics of diversification exhibit wide variation, depending on the mode of speciation, tendency for range expansion, and rate of range evolution. By varying these parameters, the model is able to capture many, but not all, of the features exhibited by birth-death trees and extant bird clades. Under scenarios with relatively stable geographic ranges, strong slowdowns in diversification rates are produced, with faster rates of range dynamics leading to constant or accelerating rates of apparent diversification. A peripatric model of speciation with stable ranges also generates highly unbalanced trees typical of bird phylogenies but fails to produce realistic range size distributions among the extant species. Results most similar to those of a birth-death process are reached under a peripatric speciation scenario with highly volatile range dynamics. Taken together, our results demonstrate that considering the geographical context of speciation and extinction provides a more conservative null model of diversification and offers a very different perspective on the phylogenetic patterns expected in the absence of ecology.
Code of Federal Regulations, 2011 CFR
2011-04-01
... with soil, watershed, wildlife, and other values. (g) Stocking rate means the authorized stocking rate... production, range utilization, land management applications being applied, and range improvements in place to...
Code of Federal Regulations, 2010 CFR
2010-04-01
... with soil, watershed, wildlife, and other values. (g) Stocking rate means the authorized stocking rate... production, range utilization, land management applications being applied, and range improvements in place to...
Li, Z F; Huang, H Y; Shi, J F; Guo, C G; Zou, S M; Liu, C C; Wang, Y; Wang, L; Zhu, S L; Wu, S L; Dai, M
2017-02-10
Objective: To review the worldwide studies on natural history models among colorectal cancer (CRC), and to inform building a Chinese population-specific CRC model and developing a platform for further evaluation of CRC screening and other interventions in population in China. Methods: A structured literature search process was conducted in PubMed and the target publication dates were from January 1995 to December 2014. Information about classification systems on both colorectal cancer and precancer on corresponding transition rate, were extracted and summarized. Indicators were mainly expressed by the medians and ranges of annual progression or regression rate. Results: A total of 24 studies were extracted from 1 022 studies, most were from America ( n =9), but 2 from China including 1 from the mainland area, mainly based on Markov model ( n =22). Classification systems for adenomas included progression risk ( n =9) and the sizes of adenoma ( n =13, divided into two ways) as follows: 1) Based on studies where adenoma was risk-dependent, the median annual transition rates, from ' normal status' to ' non-advanced adenoma', 'non-advanced' to ' advanced' and ' advanced adenoma' to CRC were 0.016 0 (range: 0.002 2-0.020 0), 0.020 (range: 0.002-0.177) and 0.044 (range: 0.005-0.063), respectively. 2) Median annual transition rates, based on studies where adenoma were classified by sizes, into <10 mm and ≥10 mm ( n =7), from ' normal' to adenoma <10 mm, from adenoma <10 mm to adenoma ≥10 mm and adenoma ≥ 10 mm to CRC, were 0.016 7 (range: 0.015 0-0.037 0), 0.020 (range: 0.015-0.035) and 0.040 0 (range: 0.008 5-0.050 0), respectively. 3) Median annual transition rates, based on studies where adenoma, were classified by sizes into diminutive (≤5 mm), small (6-9 mm) and large adenoma (≥10 mm) ( n =6), from ' normal' to diminutive adenoma,'diminutive' to ' small','small' to ' large', and large adenoma to CRC were 0.013 (range: 0.009-0.019), 0.043 (range: 0.020-0.085), 0.044 (range: 0.020-0.125) and 0.033 5 (range: 0.030-0.040), respectively. Staging system of CRC mainly included LRD (localized/regional/distant, n =10), Dukes' ( n =7) and TNM ( n =3). When using the LRD classification, the median annual transition rates from ' localized' to ' regional' and ' regional' to 'distant' were 0.28 (range: 0.20-0.33) and 0.40 (range: 0.24-0.63), respectively. Under the Dukes' classification, the median annual transition rates appeared as 0.583 (range: 0.050-0.910), 0.656 (range: 0.280-0.720) and 0.830 (range: 0.630-0.865) from Dukes' A to B, B to C and C to Dukes' D, respectively. Again, when using the TNM classification, very limited transition rate was reported. Serrated pathway was only described in one study. Conclusions: Studies on the natural history model of colorectal cancer was still limited worldwide. Adenoma seemed the most common status setting for precancer model, and the risk-dependent classification for adenoma was consistent with the most commonly used system in clinical practice as well as major cancer screening programs in China. Since the staging systems of cancers varied, and shortage of transition rates based on TNM classification (commonly used in China), there will be a challenge for building Chinese population-specific natural history model of colorectal cancer, information from other classification systems could be conditionally applied.
Droplet Diameter and Size Distribution of JP-4 Fuel Injected into a Subsonic Airstream
1975-04-01
Pressure TF1 /2 Fuel Temperatures WFL1/2 Low-Range Flow Rate WFM1/2 Mid-Range Flow Rate WFH1/2 High-Range Flow Rate Metering Orifices Manual...Millivolt Tables Plenum Tempera- ture, TP1, •F — ±0.27"F 100 — + 1.8*F ±2.3"F -10 to 70* F Data Acquisition System f f Fuel Supply TF1 — TF2
Time course of dynamic range adaptation in the auditory nerve
Wang, Grace I.; Dean, Isabel; Delgutte, Bertrand
2012-01-01
Auditory adaptation to sound-level statistics occurs as early as in the auditory nerve (AN), the first stage of neural auditory processing. In addition to firing rate adaptation characterized by a rate decrement dependent on previous spike activity, AN fibers show dynamic range adaptation, which is characterized by a shift of the rate-level function or dynamic range toward the most frequently occurring levels in a dynamic stimulus, thereby improving the precision of coding of the most common sound levels (Wen B, Wang GI, Dean I, Delgutte B. J Neurosci 29: 13797–13808, 2009). We investigated the time course of dynamic range adaptation by recording from AN fibers with a stimulus in which the sound levels periodically switch from one nonuniform level distribution to another (Dean I, Robinson BL, Harper NS, McAlpine D. J Neurosci 28: 6430–6438, 2008). Dynamic range adaptation occurred rapidly, but its exact time course was difficult to determine directly from the data because of the concomitant firing rate adaptation. To characterize the time course of dynamic range adaptation without the confound of firing rate adaptation, we developed a phenomenological “dual adaptation” model that accounts for both forms of AN adaptation. When fitted to the data, the model predicts that dynamic range adaptation occurs as rapidly as firing rate adaptation, over 100–400 ms, and the time constants of the two forms of adaptation are correlated. These findings suggest that adaptive processing in the auditory periphery in response to changes in mean sound level occurs rapidly enough to have significant impact on the coding of natural sounds. PMID:22457465
NASA Astrophysics Data System (ADS)
Escalante, George
2017-05-01
Weak Value Measurements (WVMs) with pre- and post-selected quantum mechanical ensembles were proposed by Aharonov, Albert, and Vaidman in 1988 and have found numerous applications in both theoretical and applied physics. In the field of precision metrology, WVM techniques have been demonstrated and proven valuable as a means to shift, amplify, and detect signals and to make precise measurements of small effects in both quantum and classical systems, including: particle spin, the Spin-Hall effect of light, optical beam deflections, frequency shifts, field gradients, and many others. In principal, WVM amplification techniques are also possible in radar and could be a valuable tool for precision measurements. However, relatively limited research has been done in this area. This article presents a quantum-inspired model of radar range and range-rate measurements of arbitrary strength, including standard and pre- and post-selected measurements. The model is used to extend WVM amplification theory to radar, with the receive filter performing the post-selection role. It is shown that the description of range and range-rate measurements based on the quantum-mechanical measurement model and formalism produces the same results as the conventional approach used in radar based on signal processing and filtering of the reflected signal at the radar receiver. Numerical simulation results using simple point scatterrer configurations are presented, applying the quantum-inspired model of radar range and range-rate measurements that occur in the weak measurement regime. Potential applications and benefits of the quantum inspired approach to radar measurements are presented, including improved range and Doppler measurement resolution.
Remote operation of an orbital maneuvering vehicle in simulated docking maneuvers
NASA Technical Reports Server (NTRS)
Brody, Adam R.
1990-01-01
Simulated docking maneuvers were performed to assess the effect of initial velocity on docking failure rate, mission duration, and delta v (fuel consumption). Subjects performed simulated docking maneuvers of an orbital maneuvering vehicle (OMV) to a space station. The effect of the removal of the range and rate displays (simulating a ranging instrumentation failure) was also examined. Naive subjects were capable of achieving a high success rate in performing simulated docking maneuvers without extensive training. Failure rate was a function of individual differences; there was no treatment effect on failure rate. The amount of time subjects reserved for final approach increased with starting velocity. Piloting of docking maneuvers was not significantly affected in any way by the removal of range and rate displays. Radial impulse was significant both by subject and by treatment. NASA's 0.1 percent rule, dictating an approach rate no greater than 0.1 percent of the range, is seen to be overly conservative for nominal docking missions.
Fatigue crack growth theory and experiment: A comparative analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sananda, K.
A number of theoretical models have been proposed in the literature which explain the second or the fourth power dependence of fatigue crack growth rate on ..delta..K, the stress intensity factor range in the Paris-Erdogan relation da/dN = C ..delta..K /SUP m/ . All of these models pertain to the intermediate range of crack growth rates where the m values are relatively low in the range of 2 to 4. The values of m for many metals and alloys can be much larger than 4 at near threshold crack growth rates or at stress intensities close to the fast fracture,more » and in some cases throughout the range of ..delta..K when the faceted mode of crack growth occurs. For such cases, the models appear to have no relevance. In this report predictions of different theoretical models are critically examined in comparison to experimentally determined crack growth rates in a MA 956, oxide dispersion strengthened alloy. Cumulative damage models predict crack growth rates reasonably well except in the range where ductile striations are observed. Lack of agreement with any particular model in this range is related to the fact that at different regions across the specimen thickness different mechanisms, either plastic blunting or cumulative damage, control the crack growth.« less
Dynamic Tensile Properties of Iron and Steels for a Wide Range of Strain Rates and Strain
NASA Astrophysics Data System (ADS)
Kojima, Nobusato; Hayashi, Hiroyuki; Yamamoto, Terumi; Mimura, Koji; Tanimura, Shinji
The tensile stress-strain curves of iron and a variety of steels, covering a wide range of strength level, over a wide strain rate range on the order of 10-3 ~ 103 s-1, were obtained systematically by using the Sensing Block Type High Speed Material Testing System (SBTS, Saginomiya). Through intensive analysis of these results, the strain rate sensitivity of the flow stress for the large strain region, including the viscous term at high strain rates, the true fracture strength and the true fracture strain were cleared for the material group of the ferrous metals. These systematical data may be useful to develop a practical constitutive model for computer codes, including a fracture criterion for simulations of the dynamic behavior in crash worthiness studies and of work-pieces subjected to dynamic plastic working for a wide strain rate range.
Extended range radiation dose-rate monitor
Valentine, Kenneth H.
1988-01-01
An extended range dose-rate monitor is provided which utilizes the pulse pileup phenomenon that occurs in conventional counting systems to alter the dynamic response of the system to extend the dose-rate counting range. The current pulses from a solid-state detector generated by radiation events are amplified and shaped prior to applying the pulses to the input of a comparator. The comparator generates one logic pulse for each input pulse which exceeds the comparator reference threshold. These pulses are integrated and applied to a meter calibrated to indicate the measured dose-rate in response to the integrator output. A portion of the output signal from the integrator is fed back to vary the comparator reference threshold in proportion to the output count rate to extend the sensitive dynamic detection range by delaying the asymptotic approach of the integrator output toward full scale as measured by the meter.
Photon Counting Detectors for the 1.0 - 2.0 Micron Wavelength Range
NASA Technical Reports Server (NTRS)
Krainak, Michael A.
2004-01-01
We describe results on the development of greater than 200 micron diameter, single-element photon-counting detectors for the 1-2 micron wavelength range. The technical goals include quantum efficiency in the range 10-70%; detector diameter greater than 200 microns; dark count rate below 100 kilo counts-per-second (cps), and maximum count rate above 10 Mcps.
NASA Astrophysics Data System (ADS)
Schoettle, E.; Burbank, D. W.; Bookhagen, B.
2014-12-01
California's Sierra Madre Mountains lie at the junction of the Coast and Transverse Ranges, where they form an arcuate range crest with peak elevations of nearly 1,800 m. Near the range crest, a gently sloping paleovalley in the Southern Sierra Madre is being consumed by the headward migration of a prominent knickpoint, with an ~250-m-high headwall abutting below the gently sloped paleovalley. This paleovalley at 1400 m elevation and other low-relief, high-elevation remnants in the Sierra Madres at elevations from 800-1400 m show that the range is young enough to have regions not yet in equilibrium with the modern base level and uplift rate. Toward the western end of the Sierra Madre, the Cuyama River cuts a bedrock canyon through the range. The canyon planform describes a meandering river that has now incised ~400 m into the range. The combination of (i) high-altitude, low-relief surfaces in the Sierra Madre including the paleovalley with (ii) a meandering planform that has been incised into bedrock by a transverse river suggests (1) a low-altitude meandering proto-Cuyama river preceded significant rock uplift, and (2) the river's incision records the rock uplift of the range. Using cosmogenic nuclides to measure both the bedrock-lowering rate of the high-elevation paleovalley and the erosion rate of the steep catchment eroding into it, we can place some limits on the timing and magnitude of rock uplift in the range. By dating bedrock straths along the river canyon's walls, we can directly quantify the pace of channel incision. Together these new estimates will yield an improved reconstruction of the timing, magnitude, and rate of rock uplift of the Sierra Madre.
Quantifying salinity and season effects on eastern oyster clearance and oxygen consumption rates
Casas, S.M.; Lavaud, Romain; LaPeyre, Megan K.; Comeau, L. A.; Filgueira, R.; LaPeyre, Jerome F.
2018-01-01
There are few data on Crassostrea virginica physiological rates across the range of salinities and temperatures to which they are regularly exposed, and this limits the applicability of growth and production models using these data. The objectives of this study were to quantify, in winter (17 °C) and summer (27 °C), the clearance and oxygen consumption rates of C. virginica from Louisiana across a range of salinities typical of the region (3, 6, 9, 15 and 25). Salinity and season (temperature and reproduction) affected C. virginica physiology differently; salinity impacted clearance rates with reduced feeding rates at low salinities, while season had a strong effect on respiration rates. Highest clearance rates were found at salinities of 9–25, with reductions ranging from 50 to 80 and 90 to 95% at salinities of 6 and 3, respectively. Oxygen consumption rates in summer were four times higher than in winter. Oxygen consumption rates were within a narrow range and similar among salinities in winter, but varied greatly among individuals and salinities in summer. This likely reflected varying stages of gonad development. Valve movements measured at the five salinities indicated oysters were open 50–60% of the time in the 6–25 salinity range and ~ 30% at a salinity of 3. Reduced opening periods, concomitant with narrower valve gap amplitudes, are in accord with the limited feeding at the lowest salinity (3). These data indicate the need for increased focus on experimental determination of optimal ranges and thresholds to better quantify oyster population responses to environmental changes.
Testing for clustering at many ranges inflates family-wise error rate (FWE).
Loop, Matthew Shane; McClure, Leslie A
2015-01-15
Testing for clustering at multiple ranges within a single dataset is a common practice in spatial epidemiology. It is not documented whether this approach has an impact on the type 1 error rate. We estimated the family-wise error rate (FWE) for the difference in Ripley's K functions test, when testing at an increasing number of ranges at an alpha-level of 0.05. Case and control locations were generated from a Cox process on a square area the size of the continental US (≈3,000,000 mi2). Two thousand Monte Carlo replicates were used to estimate the FWE with 95% confidence intervals when testing for clustering at one range, as well as 10, 50, and 100 equidistant ranges. The estimated FWE and 95% confidence intervals when testing 10, 50, and 100 ranges were 0.22 (0.20 - 0.24), 0.34 (0.31 - 0.36), and 0.36 (0.34 - 0.38), respectively. Testing for clustering at multiple ranges within a single dataset inflated the FWE above the nominal level of 0.05. Investigators should construct simultaneous critical envelopes (available in spatstat package in R), or use a test statistic that integrates the test statistics from each range, as suggested by the creators of the difference in Ripley's K functions test.
System and Method for Scan Range Gating
NASA Technical Reports Server (NTRS)
Lindemann, Scott (Inventor); Zuk, David M. (Inventor)
2017-01-01
A system for scanning light to define a range gated signal includes a pulsed coherent light source that directs light into the atmosphere, a light gathering instrument that receives the light modified by atmospheric backscatter and transfers the light onto an image plane, a scanner that scans collimated light from the image plane to form a range gated signal from the light modified by atmospheric backscatter, a control circuit that coordinates timing of a scan rate of the scanner and a pulse rate of the pulsed coherent light source so that the range gated signal is formed according to a desired range gate, an optical device onto which an image of the range gated signal is scanned, and an interferometer to which the image of the range gated signal is directed by the optical device. The interferometer is configured to modify the image according to a desired analysis.
Long and Short Range Correlations in Healthy and Pathologic Human Cardiac Prosses
NASA Astrophysics Data System (ADS)
Bunde, Armin
2001-03-01
Healthy sleep consists of several stages: deep sleep, light sleep and REM sleep. In this talk, recent work on the characterization of heart-rates in the three stages by long-range correlations is presented. Only in REM sleep, long-range correlations reminiscent to the wake phase occur, and the heart-rates show multifractal behaviour. In contrast, in non-REM phases, the heart-rates are uncorrelated above the typical breathing cycle time, pointing to a random regulation of the heartbeat during non-REM sleep. In deep sleep, the heart-rates show simple multifractal behaviour.
Validation of serum free light chain reference ranges in primary care.
Galvani, Luca; Flanagan, Jane; Sargazi, Mansour; Neithercut, William D
2016-05-01
The demand for measurement of serum immunoglobulin free kappa (κ) and lambda (λ) light chains has increased. The κ:λ ratio is used to assist in diagnosis/monitoring of plasma cell disorders. The binding site reference range for serum-free light chain κ:λ ratios of 0.26-1.65 was derived from healthy volunteers. Subsequently, a reference range of 0.37-3.1 for patients with chronic kidney disease has been proposed. Elevated free light chain concentrations and borderline raised free light chain ratios also may be found in polyclonal gammopathies and with other non-renal illnesses. This assessment was conducted to validate the established free light chain reference ranges in individuals from primary care. A total of 130 samples were identified from routine blood samples collected in primary care for routine biochemistry testing and estimated glomerular filtration rate calculation. The median and range of κ:λ ratios found in each estimated glomerular filtration rate group used for chronic kidney disease classification were higher than previously described. This was the case for individuals with normal or essentially normal renal function with estimated glomerular filtration rates>90, (0.58-1.76) and estimated glomerular filtration rate of 60-90 mL/min/1.73 m(2), (0.71-1.93). Individuals with estimated glomerular filtration rate 15-30, (0.72-4.50) and estimated glomerular filtration rate <15 ml/min/1.73 m(2) (0.71-4.95) also had higher values when compared to the current renal reference range of 0.37-3.10. Elevation of free light chain-κ:λ ratios may occur in the absence of a reduced renal function shown by a normal estimated glomerular filtration rate and in the presence of reduced renal function by estimated glomerular filtration rate when comparing results with the established reference ranges. Explanations include choice of analytical systems or the presence of other concurrent non-plasma cell illness. © The Author(s) 2016.
NASA Astrophysics Data System (ADS)
Young, H.; Hilley, G. E.; Kiefer, K.; Blisniuk, K.
2015-12-01
We report new, 10-Be-derived denudation rates measured from river sands in basins of the Santa Lucia Range, central California. The Santa Lucia Mountains of the California Coast Range are an asymmetrical northwest-southeast trending range bounded by the San Gregorio-Hosgri (SG-HFZ ) and Rinconada-Reliz faults. This area provides an additional opportunity to analyze the relationships between topographic form, denudation rates, and mapped underlying geologic substrate in an actively deforming landscape. Analysis of in situ-produced 10-Be from alluvial sand samples collected in the Santa Lucia Mountains has yielded measurements of spatially varying basin-scale denudation rates. Despite the impressive relief of the Santa Lucia's, denudation rates within catchments draining the coastal side of the range are uniformly low, generally varying between ~90 m/Myr and ~350 m/Myr, with one basin eroding at ~500 m/Myr. Preliminary data suggest the lowest erosion rates are located within the northern interior of the range in sedimentary and granitic lithologies, while higher rates are located directly along the coast in metasedimentary bedrock. This overall trend is punctuated by a single high denudation rate, which is hosted by a watershed whose geometry suggests that it previously has, and continues to experience divide migration as it captures the adjacent watershed's area. Spatial distribution of basins with higher denudation rates is inferred to indicate a zone of uplift adjacent to the SG-HFZ. We compare erosion rates to basin mean channel steepness index, extracted from a 10 m digital elevation model. Denudation rate generally increases with channel steepness index until ~250 m/Myr, at which point the relationship becomes invariant, suggesting a non-linear erosion model may best characterize this region. These hypotheses will be tested further as additional denudation rate results are analyzed.
Duan, Chenlong; Sheng, Cheng; Wu, Lingling; Zhao, Yuemin; He, Jinfeng; Zhou, Enhui
2014-01-01
Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (-0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed's fluid flow field. For 0.5-0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25-0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (-0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution.
A study of 35-ghz radar-assisted orbital maneuvering vehicle/space telescope docking
NASA Technical Reports Server (NTRS)
Mcdonald, M. W.
1986-01-01
An experiment was conducted to study the effects of measuring range and range rate information from a complex radar target (a one-third scale model of the Edwin P. Hubble Space Telescope). The radar ranging system was a 35-GHz frequency-modulated continuous wave unit developed in the Communication Systems Branch of the Information and Electronic Systems Laboratory at Marshall Space Flight Cneter. Measurements were made over radar-to-target distances of 5 meters to 15 meters to simulate the close distance realized in the final stages of space vehicle docking. The Space Telescope model target was driven by an antenna positioner through a range of azimuth and elevation (pitch) angles to present a variety of visual aspects of the aft end to the radar. Measurements were obtained with and without a cube corner reflector mounted in the center of the aft end of the model. The results indicate that range and range rate measurements are performed significantly more accurately with the cooperative radar reflector affixed. The results further reveal that range rate (velocity) can be measured accurately enough to support the required soft docking with the Space Telescope.
NASA Astrophysics Data System (ADS)
Tsuji, Hidenobu; Imaki, Masaharu; Kotake, Nobuki; Hirai, Akihito; Nakaji, Masaharu; Kameyama, Shumpei
2017-03-01
We demonstrate a range imaging pulsed laser sensor with two-dimensional scanning of a transmitted beam and a scanless receiver using a high-aspect avalanche photodiode (APD) array for the eye-safe wavelength. The system achieves a high frame rate and long-range imaging with a relatively simple sensor configuration. We developed a high-aspect APD array for the wavelength of 1.5 μm, a receiver integrated circuit, and a range and intensity detector. By combining these devices, we realized 160×120 pixels range imaging with a frame rate of 8 Hz at a distance of about 50 m.
Wattles, David W.; DeStefano, Stephen
2013-01-01
Moose (Alces alces) have recently re-occupied a portion of their range in the temperate deciduous forest of the northeastern United States after a >200 year absence. In southern New England, moose encounter different forest types, more human development, and higher temperatures than in other parts of their geographic range in North America. We analyzed seasonal minimum convex polygon home ranges, utilization distributions, movement rates, and home range composition of GPS-collared moose in Massachusetts. Seasonal home range sizes were not different for males and females and were within the range reported for low latitudes elsewhere in North America. Seasonal movement patterns reflected the seasonal changes in metabolic rate and the influence of the species’ reproductive cycle and weather. Home ranges consisted almost entirely of forested habitat, included large amounts of conservation land, and had lower road densities as compared to the landscape as a whole, indicating that human development may be a limiting factor for moose in the region. The size and configuration of home ranges, seasonal movement patterns, and use relative to human development have implications for conservation of moose and other wide-ranging species in more highly developed portions of their ranges.
Simard, Peter; Hibbard, Ashley L; McCallister, Kimberly A; Frankel, Adam S; Zeddies, David G; Sisson, Geoffrey M; Gowans, Shannon; Forys, Elizabeth A; Mann, David A
2010-01-01
Trained odontocetes appear to have good control over the timing (pulse rate) of their echolocation clicks; however, there is comparatively little information about how free-ranging odontocetes modify their echolocation in relation to their environment. This study investigates echolocation pulse rate in 14 groups of free-ranging bottlenose dolphins (Tursiops truncatus) at a variety of depths (2.4-30.1 m) in the Gulf of Mexico. Linear regression models indicated a significant decrease in mean pulse rate with mean water depth. Pulse rates for most groups were multi-modal. Distance to target estimates were as high as 91.8 m, assuming that echolocation was produced at a maximal rate for the target distance. A 5.29-ms processing lag time was necessary to explain the pulse rate modes observed. Although echolocation is likely reverberation limited, these results support the hypotheses that free-ranging bottlenose dolphins in this area are adapting their echolocation signals for a variety of target detection and ranging purposes, and that the target distance is a function of water depth.
Code of Federal Regulations, 2010 CFR
2010-01-01
... range for a GM employee) or, if applicable, a retained rate. Pay schedule means a set of rate ranges..., convenience, or personal advantage. A reduction in grade or pay that is caused or influenced by a management...
Dumont, Frédéric; Marechal, Pierre-André; Gervais, Patrick
2006-02-01
The purpose of this study was to examine cell viability after freezing. Two distinct ranges of temperature were identified as corresponding to stages at which yeast cell mortality occurred during freezing to -196 degrees C. The upper temperature range was related to the temperature of crystallization of the medium, which was dependent on the solute concentration; in this range mortality was prevented by high solute concentrations, and the proportion of the medium in the vitreous state was greater than the proportion in the crystallized state. The lower temperature range was related to recrystallization that occurred during thawing. Mortality in this temperature range was increased by a high cooling rate and/or high solute concentration in the freezing medium and a low temperature (less than -70 degrees C). However, a high rate of thawing prevented yeast mortality in this lower temperature range. Overall, it was found that cell viability could be conserved better under freezing conditions by increasing the osmotic pressure of the medium and by using an increased warming rate.
Involvement of Two Specific Causes of Cell Mortality in Freeze-Thaw Cycles with Freezing to −196°C
Dumont, Frédéric; Marechal, Pierre-André; Gervais, Patrick
2006-01-01
The purpose of this study was to examine cell viability after freezing. Two distinct ranges of temperature were identified as corresponding to stages at which yeast cell mortality occurred during freezing to −196°C. The upper temperature range was related to the temperature of crystallization of the medium, which was dependent on the solute concentration; in this range mortality was prevented by high solute concentrations, and the proportion of the medium in the vitreous state was greater than the proportion in the crystallized state. The lower temperature range was related to recrystallization that occurred during thawing. Mortality in this temperature range was increased by a high cooling rate and/or high solute concentration in the freezing medium and a low temperature (less than −70°C). However, a high rate of thawing prevented yeast mortality in this lower temperature range. Overall, it was found that cell viability could be conserved better under freezing conditions by increasing the osmotic pressure of the medium and by using an increased warming rate. PMID:16461684
Solidification in direct metal deposition by LENS processing
NASA Astrophysics Data System (ADS)
Hofmeister, William; Griffith, Michelle
2001-09-01
Thermal imaging and metallographic analysis were used to study Laser Engineered Net Shaping (LENS™) processing of 316 stainless steel and H13 tool steel. The cooling rates at the solid-liquid interface were measured over a range of conduction conditions. The length scale of the molten zone controls cooling rates during solidification in direct metal deposition. In LENS processing, the molten zone ranges from 0.5 mm in length to 1.5 mm, resulting in cooling rates at the solid-liquid interface ranging from 200 6,000 Ks-1.
Survival of Poliovirus in Flowing Turbid Seawater Treated with Ultraviolet Light
Hill, W. F.; Hamblet, F. E.; Akin, E. W.
1967-01-01
The effectiveness of a model ultraviolet (UV) radiation unit for treating flowing turbid seawater contaminated with poliovirus was determined. At a turbidity of 70 ppm, the observed survival ratios ranged from 1.9 × 10-3 (99.81% reduction) to 1.5 × 10-4 (99.98% reduction) at flow rates ranging from 25 to 15 liters/min; no virus was recovered at flow rates of 10 and 5 liters/min. At a turbidity of 240 ppm, the observed survival ratios ranged from 3.2 × 10-2 (96.80% reduction) to 2.1 × 10-4 (99.98% reduction) at flow rates ranging from 25 to 5 liters/min. As expected, turbidity had an adverse influence on the effectiveness of UV radiation; however, by adjusting the flow rate of the seawater through the treatment unit, adequate disinfection was shown to be predictable. Images Fig. 1 PMID:4291955
NASA Technical Reports Server (NTRS)
1972-01-01
A Tracking and Data Relay Satellite System (TDRSS) concept for service of low and medium data rate user spacecraft has been defined. The TDRS system uses two geosynchronous dual spin satellites compatible with Delta 2914 to provide command, tracking, and telemetry service between multiple low earth orbiting users and a centrally located ground station. The low data rate user service capability via each TDRS is as follows: (1) forward link at UHF: voice to one user, commands to 20 users (sequential), range and range rate service, and (2) return link at VHF: voice from one user, data from 20 users (simultaneous), range and range rate return signals. The medium data rate user service via each TDRS is as follows: (1) forward link at S band: voice or command and tracking signals to one user, and (2) return link at S band: voice, data and tracking signals from one user "order wire" for high priority service requests (implemented with an earth coverage antenna).
Reproduction in moose at their southern range limit
Ruprecht, Joel S.; Hersey, Kent R.; Hafen, Konrad; Monteith, Kevin L.; DeCesare, Nicholas J.; Kauffman, Matthew J.; MacNulty, Daniel R.
2016-01-01
Reproduction is a critical fitness component in large herbivores. Biogeographic models predict that populations occurring at the edges of the range may have compromised reproductive rates because of inferior habitat at range peripheries. When reproductive rates are chronically low, ungulate populations may lack the resiliency to rebound quickly after periods of environmental stress, and this effect may be greatest for heat-sensitive organisms at their southern range limit. To assess the demographic vulnerability of moose ( Alces alces ), we studied relationships between reproductive rates, maternal age, and rump fat in the southernmost naturally occurring moose population in North America. For prime-aged moose in our study, pregnancy rates were high (92%), but moose aged < 3 or > 9 years had low pregnancy rates (32% and 38%, respectively). The relationship between rump fat and pregnancy was nonlinear such that a threshold of at least 2mm of rump fat yielded a high probability of being pregnant midwinter. In contrast, among pregnant moose, the probability of both producing a calf and recruiting it until spring increased linearly with rump fat. We also conducted a meta-analysis of pregnancy and twinning rates for adult (≥ 2 years) moose across a latitudinal gradient to compare reproductive rates from our study to other populations in North America. Moose living at southern latitudes tended to have lower reproductive rates than those living in the core of moose range, implying that southern moose populations may be demographically more vulnerable than northern moose populations.
CO2 laser ranging systems study
NASA Technical Reports Server (NTRS)
Filippi, C. A.
1975-01-01
The conceptual design and error performance of a CO2 laser ranging system are analyzed. Ranging signal and subsystem processing alternatives are identified, and their comprehensive evaluation yields preferred candidate solutions which are analyzed to derive range and range rate error contributions. The performance results are presented in the form of extensive tables and figures which identify the ranging accuracy compromises as a function of the key system design parameters and subsystem performance indexes. The ranging errors obtained are noted to be within the high accuracy requirements of existing NASA/GSFC missions with a proper system design.
Rim, Donghyun; Wallace, Lance; Nabinger, Steven; Persily, Andrew
2012-08-15
Cooking stoves, both gas and electric, are one of the strongest and most common sources of ultrafine particles (UFP) in homes. UFP have been shown to be associated with adverse health effects such as DNA damage and respiratory and cardiovascular diseases. This study investigates the effectiveness of kitchen exhaust hoods in reducing indoor levels of UFP emitted from a gas stove and oven. Measurements in an unoccupied manufactured house monitored size-resolved UFP (2 nm to 100 nm) concentrations from the gas stove and oven while varying range hood flow rate and burner position. The air change rate in the building was measured continuously based on the decay of a tracer gas (sulfur hexafluoride, SF(6)). The results show that range hood flow rate and burner position (front vs. rear) can have strong effects on the reduction of indoor levels of UFP released from the stove and oven, subsequently reducing occupant exposure to UFP. Higher range hood flow rates are generally more effective for UFP reduction, though the reduction varies with particle diameter. The influence of the range hood exhaust is larger for the back burner than for the front burner. The number-weighted particle reductions for range hood flow rates varying between 100 m(3)/h and 680 m(3)/h range from 31% to 94% for the front burner, from 54% to 98% for the back burner, and from 39% to 96% for the oven. Copyright © 2012 Elsevier B.V. All rights reserved.
Spatial-temporal population dynamics across species range: from center to margin
Guo, Q.; Taper, M.L.; Schoenberger, M.; Brandl, J.
2005-01-01
Understanding the boundaries of species' ranges and the variations in population dynamics from the centre to margin of a species' range is critical. This study simulated spatial-temporal patterns of birth and death rates and migration across a species' range in different seasons. Our results demonstrated the importance of dispersal and migration in altering birth and death rates, balancing source and sink habitats, and governing expansion or contraction of species' ranges in changing environments. We also showed that the multiple equilibria of metapopulations across a species' range could be easily broken following climatic changes or physical disturbances either or local or regional. Although we refer to our models as describing the population dynamics across whole species' range, they should also apply to small-scale habitats (metapopulations) in which species abundance follows a humped pattern or to any ecosystem or landscape where strong central-marginal (C-M) environmental gradients exist. Conservation of both central and marginal populations would therefore be equally important considerations in making management decisions.
Spatial-temporal population dynamics across species range: From centre to margin
Guo, Q.; Taper, M.; Schoenberger, M.; Brandle, J.
2005-01-01
Understanding the boundaries of species' ranges and the variations in population dynamics from the centre to margin of a species' range is critical. This study simulated spatial-temporal patterns of birth and death rates and migration across a species' range in different seasons. Our results demonstrated the importance of dispersal and migration in altering birth and death rates, balancing source and sink habitats, and governing expansion or contraction of species' ranges in changing environments. We also showed that the multiple equilibria of metapopulations across a species' range could be easily broken following climatic changes or physical disturbances either local or regional. Although we refer to our models as describing the population dynamics across whole species' range, they should also apply to small-scale habitats (metapopulations) in which species abundance follows a humped pattern or to any ecosystem or landscape where strong central-marginal (C-M) environmental gradients exist. Conservation of both central and marginal populations would therefore be equally important considerations in making management decisions.
Rodrigues, Juliana DE O; Lorenzo, Marcelo G; Martins-Filho, Olindo A; Elliot, Simon L; Guarneri, Alessandra A
2016-09-01
Trypanosoma rangeli is a protozoan parasite, which does not cause disease in humans, although it can produce different levels of pathogenicity to triatomines, their invertebrate hosts. We tested whether infection imposed a temperature-dependent cost on triatomine fitness using T. rangeli with different life histories. Parasites cultured only in liver infusion tryptose medium (cultured) and parasites exposed to cyclical passages through mice and triatomines (passaged) were used. We held infected insects at four temperatures between 21 and 30 °C and measured T. rangeli growth in vitro at the same temperatures in parallel. Overall, T. rangeli infection induced negative effects on insect fitness. In the case of cultured infection, parasite effects were temperature-dependent. Intermoult period, mortality rates and ecdysis success were affected in those insects exposed to lower temperatures (21 and 24 °C). For passaged-infected insects, the effects were independent of temperature, intermoult period being prolonged in all infected groups. Trypanosoma rangeli seem to be less tolerant to higher temperatures since cultured-infected insects showed a reduction in the infection rates and passaged-infected insects decreased the salivary gland infection rates in those insects submitted to 30 °C. In vitro growth of T. rangeli was consistent with these results.
Sheng, Cheng; Wu, Lingling; Zhao, Yuemin; He, Jinfeng; Zhou, Enhui
2014-01-01
Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (−0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed's fluid flow field. For 0.5–0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25–0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (−0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution. PMID:25379546
Inostroza-Michael, Oscar; Hernández, Cristián E; Rodríguez-Serrano, Enrique; Avaria-Llautureo, Jorge; Rivadeneira, Marcelo M
2018-05-01
Among the earliest macroecological patterns documented, is the range and body size relationship, characterized by a minimum geographic range size imposed by the species' body size. This boundary for the geographic range size increases linearly with body size and has been proposed to have implications in lineages evolution and conservation. Nevertheless, the macroevolutionary processes involved in the origin of this boundary and its consequences on lineage diversification have been poorly explored. We evaluate the macroevolutionary consequences of the difference (hereafter the distance) between the observed and the minimum range sizes required by the species' body size, to untangle its role on the diversification of a Neotropical species-rich bird clade using trait-dependent diversification models. We show that speciation rate is a positive hump-shaped function of the distance to the lower boundary. The species with highest and lowest distances to minimum range size had lower speciation rates, while species close to medium distances values had the highest speciation rates. Further, our results suggest that the distance to the minimum range size is a macroevolutionary constraint that affects the diversification process responsible for the origin of this macroecological pattern in a more complex way than previously envisioned. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.
Range size heritability and diversification patterns in the liverwort genus Radula.
Patiño, Jairo; Wang, Jian; Renner, Matt A M; Gradstein, S Robbert; Laenen, Benjamin; Devos, Nicolas; Shaw, A Jonathan; Vanderpoorten, Alain
2017-01-01
Why some species exhibit larger geographical ranges than others, and to what extent does variation in range size affect diversification rates, remains a fundamental, but largely unanswered question in ecology and evolution. Here, we implement phylogenetic comparative analyses and ancestral area estimations in Radula, a liverwort genus of Cretaceous origin, to investigate the mechanisms that explain differences in geographical range size and diversification rates among lineages. Range size was phylogenetically constrained in the two sub-genera characterized by their almost complete Australasian and Neotropical endemicity, respectively. The congruence between the divergence time of these lineages and continental split suggests that plate tectonics could have played a major role in their present distribution, suggesting that a strong imprint of vicariance can still be found in extant distribution patterns in these highly mobile organisms. Amentuloradula, Volutoradula and Metaradula species did not appear to exhibit losses of dispersal capacities in terms of dispersal life-history traits, but evidence for significant phylogenetic signal in macroecological niche traits suggests that niche conservatism accounts for their restricted geographic ranges. Despite their greatly restricted distribution to Australasia and Neotropics respectively, Amentuloradula and Volutoradula did not exhibit significantly lower diversification rates than more widespread lineages, in contrast with the hypothesis that the probability of speciation increases with range size by promoting geographic isolation and increasing the rate at which novel habitats are encountered. We suggest that stochastic long-distance dispersal events may balance allele frequencies across large spatial scales, leading to low genetic structure among geographically distant areas or even continents, ultimately decreasing the diversification rates in highly mobile, widespread lineages. Copyright © 2016 Elsevier Inc. All rights reserved.
Smith, C F; Gavaghan, B J; McSweeney, D; Powell, V; Lisle, A
2014-12-01
To compare the heart rates of adult free-range chickens (Gallus domesticus) measured by auscultation with a stethoscope with those measured simultaneously using electrocardiography (ECG). With each bird in a standing position, estimation of the heart rate was performed by placing a mark on paper for every 4 beats for roosters and 8 beats for hens as detected by auscultation over 30 s, while simultaneous ECG was performed. Heart rates measured by auscultation showed a high correlation (r = 0.97) with those measured by ECG. There was a high correlation between the heart rates of adult free-range chickens measured by auscultation with a stethoscope and those measured simultaneously using ECG. © 2014 Australian Veterinary Association.
NASA Technical Reports Server (NTRS)
Degnan, J. J., III; Zagwodski, T. W.
1979-01-01
A prototype Q-switched Nd:YAG laser transmitter intended for use in the NASA mobile laser ranging system was subjected to various tests of temporal pulse shape and stability, output energy and stability, beam divergence, and range bias errors. Peak to peak variations in the mean range were as large as 30 cm and drift rates of system bias with time as large as 6 mm per minute of operation were observed. The incorporation of a fast electro-optic cavity dump into the oscillator gave significantly improved results. Reevaluation of the ranging performance after modification showed a reduction in the peak to peak variation in the mean range to the 2 or 3 cm level and a drift rate of system time biases of less than 1 mm per minute of operation. A qualitative physical explanation for the superior performance of cavity dumped lasers is given.
Climate dominated topography in a tectonically active mountain range
NASA Astrophysics Data System (ADS)
Adams, B. A.; Ehlers, T. A.
2015-12-01
Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The broad spatial trend in channel steepness values suggests that the locus of high rock uplift rates is coincident with the rugged range core, in a similar position as high temperature and pressure lithologies, but not in the low lying foothills as has been previously suggested by low-temperature thermochronometry. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns. We demonstrate the same topographic effects are recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on topography makes the argument of mountain range steadiness untenable in significantly glaciated settings. Furthermore, our results suggest that most glaciated Cenozoic ranges are likely still in a mode of readjustment as fluvial systems change topography and erosion rates to equilibrate with rock uplift rates.
Estimates of Stellar Weak Interaction Rates for Nuclei in the Mass Range A=65-80
NASA Astrophysics Data System (ADS)
Pruet, Jason; Fuller, George M.
2003-11-01
We estimate lepton capture and emission rates, as well as neutrino energy loss rates, for nuclei in the mass range A=65-80. These rates are calculated on a temperature/density grid appropriate for a wide range of astrophysical applications including simulations of late time stellar evolution and X-ray bursts. The basic inputs in our single-particle and empirically inspired model are (i) experimentally measured level information, weak transition matrix elements, and lifetimes, (ii) estimates of matrix elements for allowed experimentally unmeasured transitions based on the systematics of experimentally observed allowed transitions, and (iii) estimates of the centroids of the GT resonances motivated by shell model calculations in the fp shell as well as by (n, p) and (p, n) experiments. Fermi resonances (isobaric analog states) are also included, and it is shown that Fermi transitions dominate the rates for most interesting proton-rich nuclei for which an experimentally determined ground state lifetime is unavailable. For the purposes of comparing our results with more detailed shell model based calculations we also calculate weak rates for nuclei in the mass range A=60-65 for which Langanke & Martinez-Pinedo have provided rates. The typical deviation in the electron capture and β-decay rates for these ~30 nuclei is less than a factor of 2 or 3 for a wide range of temperature and density appropriate for presupernova stellar evolution. We also discuss some subtleties associated with the partition functions used in calculations of stellar weak rates and show that the proper treatment of the partition functions is essential for estimating high-temperature β-decay rates. In particular, we show that partition functions based on unconverged Lanczos calculations can result in errors in estimates of high-temperature β-decay rates.
CFO compensation method using optical feedback path for coherent optical OFDM system
NASA Astrophysics Data System (ADS)
Moon, Sang-Rok; Hwang, In-Ki; Kang, Hun-Sik; Chang, Sun Hyok; Lee, Seung-Woo; Lee, Joon Ki
2017-07-01
We investigate feasibility of carrier frequency offset (CFO) compensation method using optical feedback path for coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. Recently proposed CFO compensation algorithms provide wide CFO estimation range in electrical domain. However, their practical compensation range is limited by sampling rate of an analog-to-digital converter (ADC). This limitation has not drawn attention, since the ADC sampling rate was high enough comparing to the data bandwidth and CFO in the wireless OFDM system. For CO-OFDM, the limitation is becoming visible because of increased data bandwidth, laser instability (i.e. large CFO) and insufficient ADC sampling rate owing to high cost. To solve the problem and extend practical CFO compensation range, we propose a CFO compensation method having optical feedback path. By adding simple wavelength control for local oscillator, the practical CFO compensation range can be extended to the sampling frequency range. The feasibility of the proposed method is experimentally investigated.
2013-03-30
canvas sling. Heart rate, respiration rate, and oxygen saturation were monitored continuously using a pulse oximeter (VetOx G2 Digital, Heska Corporation...Pre Post 30 min Mean SD Median Range Mean SD Median Range Mean SD Median Range Oxygen saturation % 93.7 2.1 93.7 91–97 63.2* 17.4 66.5 36.7–91.3 92.2...as actin in human RBC membranes [29] and human neutrophils [34]. Discussion General findings Changes in heart rate, venous-blood oxygen saturation
Bird population trends are linearly affected by climate change along species thermal ranges.
Jiguet, Frédéric; Devictor, Vincent; Ottvall, Richard; Van Turnhout, Chris; Van der Jeugd, Henk; Lindström, Ake
2010-12-07
Beyond the effects of temperature increase on local population trends and on species distribution shifts, how populations of a given species are affected by climate change along a species range is still unclear. We tested whether and how species responses to climate change are related to the populations locations within the species thermal range. We compared the average 20 year growth rates of 62 terrestrial breeding birds in three European countries along the latitudinal gradient of the species ranges. After controlling for factors already reported to affect bird population trends (habitat specialization, migration distance and body mass), we found that populations breeding close to the species thermal maximum have lower growth rates than those in other parts of the thermal range, while those breeding close to the species thermal minimum have higher growth rates. These results were maintained even after having controlled for the effect of latitude per se. Therefore, the results cannot solely be explained by latitudinal clines linked to the geographical structure in local spring warming. Indeed, we found that populations are not just responding to changes in temperature at the hottest and coolest parts of the species range, but that they show a linear graded response across their European thermal range. We thus provide insights into how populations respond to climate changes. We suggest that projections of future species distributions, and also management options and conservation assessments, cannot be based on the assumption of a uniform response to climate change across a species range or at range edges only.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cassingham, N.; Corkhill, C. L.; Backhouse, D. J.
The first comprehensive assessment of the dissolution kinetics of simulant Magnox–THORP blended UK high-level waste glass, obtained by performing a range of single-pass flow-through experiments, is reported here. Inherent forward rates of glass dissolution were determined over a temperature range of 23 to 70°C and an alkaline pH range of 8.0 to 12.0. Linear regression techniques were applied to the TST kinetic rate law to obtain fundamental parameters necessary to model the dissolution kinetics of UK high-level waste glass (the activation energy (Ea), pH power law coefficient (η) and the intrinsic rate constant (k0)), which is of importance to themore » post-closure safety case for the geological disposal of vitreous products. The activation energies based on B release ranged from 55 ± 3 to 83 ± 9 kJ mol–1, indicating that Magnox–THORP blend glass dissolution has a surface-controlled mechanism, similar to that of other high- level waste simulant glass compositions such as the French SON68 and LAW in the US. Forward dissolution rates, based on Si, B and Na release, suggested that the dissolution mechanism under dilute conditions, and pH and temperature ranges of this study, was not sensitive to composition as defined by HLW-incorporation rate.« less
The mechanical behavior of metal alloys with grain size distribution in a wide range of strain rates
NASA Astrophysics Data System (ADS)
Skripnyak, V. A.; Skripnyak, V. V.; Skripnyak, E. G.
2017-12-01
The paper discusses a multiscale simulation approach for the construction of grain structure of metals and alloys, providing high tensile strength with ductility. This work compares the mechanical behavior of light alloys and the influence of the grain size distribution in a wide range of strain rates. The influence of the grain size distribution on the inelastic deformation and fracture of aluminium and magnesium alloys is investigated by computer simulations in a wide range of strain rates. It is shown that the yield stress depends on the logarithm of the normalized strain rate for light alloys with a bimodal grain distribution and coarse-grained structure.
Spatial-temporal population dynamics across species range: from centre to margin
Qinfeng Guo; Mark Taper; Michele Schoenberger; J. Brandle
2005-01-01
Understanding the boundaries of species'rangs and the variations in population dynamics from the centre to margin of a species' range is critical. This study simulated spatial-tamporal patterns of birth and death rates and migration across a species' range in different seasons. Our results demonstrated the importance of dispersal and migration in...
Radar range data signal enhancement tracker
NASA Technical Reports Server (NTRS)
1975-01-01
The design, fabrication, and performance characteristics are described of two digital data signal enhancement filters which are capable of being inserted between the Space Shuttle Navigation Sensor outputs and the guidance computer. Commonality of interfaces has been stressed so that the filters may be evaluated through operation with simulated sensors or with actual prototype sensor hardware. The filters will provide both a smoothed range and range rate output. Different conceptual approaches are utilized for each filter. The first filter is based on a combination low pass nonrecursive filter and a cascaded simple average smoother for range and range rate, respectively. Filter number two is a tracking filter which is capable of following transient data of the type encountered during burn periods. A test simulator was also designed which generates typical shuttle navigation sensor data.
Lester, Sarah E; Ruttenberg, Benjamin I
2005-01-01
We address the conflict in earlier results regarding the relationship between dispersal potential and range size. We examine all published pelagic larval duration data for tropical reef fishes. Larval duration is a convenient surrogate for dispersal potential in marine species that are sedentary as adults and that therefore only experience significant dispersal during their larval phase. Such extensive quantitative dispersal data are only available for fishes and thus we use a unique dataset to examine the relationship between dispersal potential and range size. We find that dispersal potential and range size are positively correlated only in the largest ocean basin, the Indo-Pacific, and that this pattern is driven primarily by the spatial distribution of habitat and dispersal barriers. Furthermore, the relationship strengthens at higher taxonomic levels, suggesting an evolutionary mechanism. We document a negative correlation between species richness and larval duration at the family level in the Indo-Pacific, implying that speciation rate may be negatively related to dispersal potential. If increased speciation rate within a taxonomic group results in smaller range sizes within that group, speciation rate could regulate the association between range size and dispersal potential. PMID:16007745
Structure and Utility of Blind Speed Intervals Associated with Doppler Measurements of Range Rate
1993-02-01
computer programming concepts of speed, memory , and data structures that can be exploited to fabricate efficient software realizations of two phase range...to the effect that it is possible to derive a reasonable unambiguous estimate of range rate from the measurement of the pulse-to-pulse phase shift in...the properties of the blind speed intervals generated by the base speeds involved in two measurement equations. Sections 12 through 18 make up the
NASA Technical Reports Server (NTRS)
Little, G. R.
1976-01-01
The AN/APQ-153 fire control radar modified to provide angle tracking was evaluated for improved performance. The frequency agile modifications are discussed along with the range-rate improvement modifications, and the radar to computer interface. A parametric design and comparison of noncoherent and coherent radar systems are presented. It is shown that the shuttle rendezvous range and range-rate requirements can be made by a Ku-Band noncoherent pulse radar.
Performance of Wide Operating Temperature Range Electrolytes in Quallion Prototype Li-Ion Cells
NASA Technical Reports Server (NTRS)
Smart, M. C.; Ratnakumar, B. V.; Tomcsi, M. R.; Nagata, M.; Visco, V.; Tsukamoto, H.
2010-01-01
For a number of applications, there is a continued interest in the development of rechargeable lithium-based batteries that can effectively operate over a wide temperature range (i.e., -40 to +70 deg C). These applications include powering future planetary rovers for NASA, enabling the next generation of automotive batteries for DOE, and supporting many DOD applications. Li-ion technology has been demonstrated to have good performance over a reasonably wide temperature range with many systems; however, there is still a desire to improve the low temperature rate capacity as well as the high temperature resilience. In the current study, we would like to present recent results obtained with prototype Li-Ion cells (manufactured by Quallion, LLC) which include various wide operating temperature range electrolytes developed by both JPL and Quallion. To demonstrate the viability of the technology, a number of performance tests were carried out, including: (a) discharge rate characterization over a wide temperature range (down to -60 deg C) using various rates (up to 20C rates), (b) discharge rate characterization at low temperatures with low temperature charging, (c) variable temperature cycling over a wide temperature range (-40 to +70 deg C), and (d) cycling at high temperature (50 deg C). As will be discussed, impressive rate capability was observed at low temperatures with many systems, as well as good resilience to high temperature cycling. To augment the performance testing on the prototype cells, a number of experimental three electrodes cells were fabricated (including Li reference electrodes) to allow the determination of the lithium kinetics of the respective electrodes and interfacial properties as a function of temperatures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tercan, Fahri; Oguzkurt, Levent; Ozkan, Ugur
2008-05-15
The purpose of this study was to compare the technical success and complication rates of ultrasonography-guided central venous catheterization between adult and pediatric patients which have not been reported previously. In a 4-year period, 859 ultrasonography-guided central vein catheterizations in 688 adult patients and 247 catheterizations in 156 pediatric patients were retrospectively evaluated. Mean age was 56.3 years (range, 18 to 95 years) for adults and 3.3 years (range, 0.1 to 16.3 years) for children. The preferred catheterization site was internal jugular vein in 97% of adults and 85% of children. The technical success rate, mean number of punctures, andmore » rate of single wall puncture were 99.4%, 1.04 (range, 1-3), and 83% for adults and 90.3%, 1.25 (range, 1-5), and 49% for children, respectively. All the differences were statistically significant (p < 0.05). Complication rates were 2.3% and 2.4% for adults and children, respectively (p > 0.05). Major complications such as pneumothorax and hemothorax were not seen in any group. In conclusion, ultrasonography-guided central venous catheterization has a high technical success rate, lower puncture attempt rate, and higher single wall puncture rate in adults compared to children. Complication rates are comparable in the two groups.« less
Effect of dispersal at range edges on the structure of species ranges
Bahn, V.; O'Connor, R.J.; Krohn, W.B.
2006-01-01
Range edges are of particular interest to ecology because they hold key insights into the limits of the realized niche and associated population dynamics. A recent feature of Oikos summarized the state of the art on range edge ecology. While the typical question is what causes range edges, another important question is how range edges influence the distribution of abundances across a species geographic range when dispersal is present. We used a single species population dynamics model on a coupled-lattice to determine the effects of dispersal on peripheral populations as compared to populations at the core of the range. In the absence of resource gradients, the reduced neighborhood and thus lower connectivity or higher isolation among populations at the range edge alone led to significantly lower population sizes in the periphery of the range than in the core. Lower population sizes mean higher extinction risks and lower adaptability at the range edge, which could inhibit or slow range expansions, and thus effectively stabilize range edges. The strength of this effect depended on the potential population growth rate and the maximum dispersal distance. Lower potential population growth rates led to a stronger effect of dispersal resulting in a higher difference in population sizes between the two areas. The differential effect of dispersal on population sizes at the core and periphery of the range in the absence of resource gradients implies that traditional, habitat-based distribution models could result in misleading conclusions about the habitat quality in the periphery. Lower population sizes at the periphery are also relevant to conservation, because habitat removal not only eliminates populations but also creates new edges. Populations bordering these new edges may experience declines, due to their increased isolation. ?? OIKOS.
5 CFR 9701.322 - Setting and adjusting rate ranges.
Code of Federal Regulations, 2010 CFR
2010-01-01
... MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Setting and Adjusting Rate Ranges... operational reasons, these adjustments will become effective on or about the date of the annual General...
Analysis of GRACE Range-rate Residuals with Emphasis on Reprocessed Star-Camera Datasets
NASA Astrophysics Data System (ADS)
Goswami, S.; Flury, J.; Naeimi, M.; Bandikova, T.; Guerr, T. M.; Klinger, B.
2015-12-01
Since March 2002 the two GRACE satellites orbit the Earth at rela-tively low altitude. Determination of the gravity field of the Earth including itstemporal variations from the satellites' orbits and the inter-satellite measure-ments is the goal of the mission. Yet, the time-variable gravity signal has notbeen fully exploited. This can be seen better in the computed post-fit range-rateresiduals. The errors reflected in the range-rate residuals are due to the differ-ent sources as systematic errors, mismodelling errors and tone errors. Here, weanalyse the effect of three different star-camera data sets on the post-fit range-rate residuals. On the one hand, we consider the available attitude data andon other hand we take the two different data sets which has been reprocessedat Institute of Geodesy, Hannover and Institute of Theoretical Geodesy andSatellite Geodesy, TU Graz Austria respectively. Then the differences in therange-rate residuals computed from different attitude dataset are analyzed inthis study. Details will be given and results will be discussed.
Guirguis-Blake, Janelle M; Henderson, Jillian T; Perdue, Leslie A
2017-03-07
Recent changes in the periodicity of cervical cancer screening have led to questions about the role of screening pelvic examinations among asymptomatic women. To systematically review literature on health benefits, accuracy, and harms of the screening pelvic examination for gynecologic conditions for the US Preventive Services Task Force (USPSTF). MEDLINE, PubMed, and Cochrane Central Register of Controlled Trials for relevant English-language studies published through January 13, 2016, with surveillance through August 3, 2016. Two reviewers independently screened abstracts and studies. The search yielded 8678 unique citations; 316 full-text articles were reviewed, and 9 studies including 27 630 patients met inclusion criteria. Two reviewers rated study quality using USPSTF criteria. Morbidity; mortality; diagnostic accuracy for any gynecologic cancer or condition except cervical cancer, gonorrhea, and chlamydia, which are covered by other USPSTF screening recommendations; harms (false-positive rates, false-negative rates, surgery rates). No trials examined the effectiveness of the pelvic examination in reducing all-cause mortality, reducing cancer- and disease-specific morbidity and mortality, or improving quality of life. Eight studies reported accuracy for the screening pelvic examination: ovarian cancer (4 studies; n = 26 432), bacterial vaginosis (2 studies; n = 930), trichomoniasis (1 study; n = 779), and genital herpes (1 study; n = 779). In the 4 ovarian cancer screening studies, low prevalence of ovarian cancer consistently resulted in low positive predictive values (PPVs) and false-positive rates, with a lack of precision in accuracy estimates (sensitivity range, 0%-100%; specificity range, 91%-99%; PPV range, 0%-3.6%; negative predictive value [NPV] range, ≥99%). Each diagnostic accuracy study for bacterial vaginosis, trichomoniasis, and genital herpes was performed in a high-prevalence population with substantial proportions of symptomatic patients and reported accuracy characteristics for individual physical examination findings (bacterial vaginosis, homogeneous discharge: sensitivity range, 69%-79%; specificity range, 54%-97%; PPV range, 52%-95%; NPV range, 79%-80%; herpes simplex virus, vulvar ulcerations: sensitivity, 20%; specificity, 98%; PPV, 88%; NPV, 57%; trichomoniasis, colpitis macularis: sensitivity, 2%; specificity, 100%; PPV, 100%; NPV, 85%). Surgery rates resulting from an abnormal screening pelvic examination for ovarian cancer ranged from 5% to 36% at 1 year, with the largest study reporting an 11% surgery rate and 1% complication rate within 1 year of a screening pelvic examination with abnormal findings. No direct evidence was identified for overall benefits and harms of the pelvic examination as a 1-time or periodic screening test. Limited evidence was identified regarding the diagnostic accuracy and harms of routine screening pelvic examinations in asymptomatic primary care populations.
1998-02-12
acoustic detection rates and ranges for blue and fin whales are greater than the visual detection rates and ranges for these species. The integration of...killer whales (Mossbridge and Thomas, 1998 ). Also, difference in calls in different parts of the species’ range may not imply genetic differences as...an Acoustic Integration Model (AIM), as applied during the LFA-SRP Phase I research in Septem- ber-October 1997 involving blue and fin
Pandemic influenza-implications for critical care resources in Australia and New Zealand.
Anderson, Therese A; Hart, Graeme K; Kainer, Marion A
2003-09-01
To quantify resource requirements (additional beds and ventilator capacity), for critical care services in the event of pandemic influenza. Cross-sectional survey about existing and potential critical care resources. Participants comprised 156 of the 176 Australasian (Australia and New Zealand) critical care units on the database of the Australian and New Zealand Intensive Care Society (ANZICS) Research Centre for Critical Care Resources. The Meltzer, Cox and Fukuda model was adapted to map a range of influenza attack rate estimates for hospitalisation and episodes likely to require intensive care and to predict critical care admission rates and bed day requirements. Estimations of ventilation rates were based on those for community-acquired pneumonia. The estimated extra number of persons requiring hospitalisation ranged from 8,455 (10% attack rate) to 150,087 (45% attack rate). The estimated number of additional admissions to critical care units ranged from 423 (5% admission rate, 10% attack rate) to 37,522 (25% admission rate, 45% attack rate). The potential number of required intensive care bed days ranged from 846 bed days (2 day length of stay, 10% attack rate) to 375,220 bed days (10 day length of stay, 45% attack rate). The number of persons likely to require mechanical ventilation ranged from 106 (25% of projected critical care admissions, 10% attack rate) to 28,142 (75% of projected critical care admissions, 45% attack rate). An additional 1,195 emergency ventilator beds were identified in public sector and 248 in private sector hospitals. Cancellation of elective surgery could release a potential 76,402 intensive care bed days (per annum), but in the event of pandemic influenza, 31,150 bed days could be required over an 8- to 12-week period. Australasian critical care services would be overwhelmed in the event of pandemic influenza. More work is required in relation to modelling, contingency plans, and resource allocation.
MacDonald, Cameron W; Whitman, Julie M; Cleland, Joshua A; Smith, Marcia; Hoeksma, Hugo L
2006-08-01
Case series describing the outcomes of individual patients with hip osteoarthritis treated with manual physical therapy and exercise. Seven patients referred to physical therapy with hip osteoarthritis and/or hip pain were included in this case series. All patients were treated with manual physical therapy followed by exercises to maximize strength and range of motion. Six of 7 patients completed a Harris Hip Score at initial examination and discharge from physical therapy, and 1 patient completed a Global Rating of Change Scale at discharge. Three males and 4 females with a median age of 62 years (range, 52-80 years) and median duration of symptoms of 9 months (range, 2-60 months) participated in this case series. The median number of physical therapy sessions attended was 5 (range, 4-12). The median increase in total passive range of motion of the hip was 82 degrees (range, 70 degrees-86 degrees). The median improvement on the Harris Hip Score was 25 points (range, 15-38 points). The single patient who completed the Global Rating of Change Scale at discharge reported being "a great deal better." Numeric pain rating scores decreased by a mean of 5 points (range, 2-7 points) on 0-to-10-point scale. All patients exhibited reductions in pain and increases in passive range of motion, as well as a clinically meaningful improvement in function. Although we can not infer a cause and effect relationship from a case series, the outcomes with these patients are similar to others reported in the literature that have demonstrated superior clinical outcomes associated with manual physical therapy and exercise for hip osteoarthritis compared to exercise alone.
Bounds on Energy Absorption and Prethermalization in Quantum Systems with Long-Range Interactions
NASA Astrophysics Data System (ADS)
Ho, Wen Wei; Protopopov, Ivan; Abanin, Dmitry A.
2018-05-01
Long-range interacting systems such as nitrogen vacancy centers in diamond and trapped ions serve as experimental setups to probe a range of nonequilibrium many-body phenomena. In particular, via driving, various effective Hamiltonians with physics potentially quite distinct from short-range systems can be realized. In this Letter, we derive general rigorous bounds on the linear response energy absorption rates of periodically driven systems of spins or fermions with long-range interactions that are sign changing and fall off as 1 /rα with α >d /2 . We show that the disorder averaged energy absorption rate at high temperatures decays exponentially with the driving frequency. This strongly suggests the presence of a prethermal plateau in which dynamics is governed by an effective, static Hamiltonian for long times, and we provide numerical evidence to support such a statement. Our results are relevant for understanding timescales of heating and new dynamical regimes described by effective Hamiltonians in such long-range systems.
Local adaptation at the range peripheries of Sitka spruce.
Mimura, M; Aitken, S N
2010-02-01
High-dispersal rates in heterogeneous environments and historical rapid range expansion can hamper local adaptation; however, we often see clinal variation in high-dispersal tree species. To understand the mechanisms of the species' distribution, we investigated local adaptation and adaptive plasticity in a range-wide context in Sitka spruce, a wind-pollinated tree species that has recently expanded its range after glaciations. Phenotypic traits were observed using growth chamber experiments that mimicked temperature and photoperiodic regimes from the limits of the species realized niche. Bud phenology exhibited parallel reaction norms among populations; however, putatively adaptive plasticity and strong divergent selection were seen in bud burst and bud set timing respectively. Natural selection appears to have favoured genotypes that maximize growth rate during available frost-free periods in each environment. We conclude that Sitka spruce has developed local adaptation and adaptive plasticity throughout its range in response to current climatic conditions despite generally high pollen flow and recent range expansion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Viel, Francis; Duzenli, Cheryl; British Columbia Cancer Agency, Department of Medical Physics, Vancouver Centre
2014-08-15
Introduction: Radiation detector responses can be affected by dose rate. Due to higher dose per pulse and wider range of mu rates in FFF beams, detector responses should be characterized prior to implementation of QA protocols for FFF beams. During VMAT delivery, the MU rate may also vary dramatically within a treatment fraction. This study looks at the dose per pulse variation throughout a 3D volume for typical VMAT plans and the response characteristics for a variety of detectors, and makes recommendations on the design of QA protocols for FFF VMAT QA. Materials and Methods: Linac log file data andmore » a simplified dose calculation algorithm are used to calculate dose per pulse for a variety of clinical VMAT plans, on a voxel by voxel basis, as a function of time in a cylindrical phantom. Diode and ion chamber array responses are characterized over the relevant range of dose per pulse and dose rate. Results: Dose per pulse ranges from <0.1 mGy/pulse to 1.5 mGy/pulse in a typical VMAT treatment delivery using the 10XFFF beam. Diode detector arrays demonstrate increased sensitivity to dose (+./− 3%) with increasing dose per pulse over this range. Ion chamber arrays demonstrate decreased sensitivity to dose (+/− 1%) with increasing dose rate over this range. Conclusions: QA protocols should be designed taking into consideration inherent changes in detector sensitivity with dose rate. Neglecting to account for changes in detector response with dose per pulse can lead to skewed QA results.« less
Age differences in visual search for compound patterns: long- versus short-range grouping.
Burack, J A; Enns, J T; Iarocci, G; Randolph, B
2000-11-01
Visual search for compound patterns was examined in observers aged 6, 8, 10, and 22 years. The main question was whether age-related improvement in search rate (response time slope over number of items) was different for patterns defined by short- versus long-range spatial relations. Perceptual access to each type of relation was varied by using elements of same contrast (easy to access) or mixed contrast (hard to access). The results showed large improvements with age in search rate for long-range targets; search rate for short-range targets was fairly constant across age. This pattern held regardless of whether perceptual access to a target was easy or hard, supporting the hypothesis that different processes are involved in perceptual grouping at these two levels. The results also point to important links between ontogenic and microgenic change in perception (H. Werner, 1948, 1957).
Demographic compensation and tipping points in climate-induced range shifts.
Doak, Daniel F; Morris, William F
2010-10-21
To persist, species are expected to shift their geographical ranges polewards or to higher elevations as the Earth's climate warms. However, although many species' ranges have shifted in historical times, many others have not, or have shifted only at the high-latitude or high-elevation limits, leading to range expansions rather than contractions. Given these idiosyncratic responses to climate warming, and their varied implications for species' vulnerability to climate change, a critical task is to understand why some species have not shifted their ranges, particularly at the equatorial or low-elevation limits, and whether such resilience will last as warming continues. Here we show that compensatory changes in demographic rates are buffering southern populations of two North American tundra plants against the negative effects of a warming climate, slowing their northward range shifts, but that this buffering is unlikely to continue indefinitely. Southern populations of both species showed lower survival and recruitment but higher growth of individual plants, possibly owing to longer, warmer growing seasons. Because of these and other compensatory changes, the population growth rates of southern populations are not at present lower than those of northern ones. However, continued warming may yet prove detrimental, as most demographic rates that improved in moderately warmer years declined in the warmest years, with the potential to drive future population declines. Our results emphasize the need for long-term, range-wide measurement of all population processes to detect demographic compensation and to identify nonlinear responses that may lead to sudden range shifts as climatic tipping points are exceeded.
Hip fusion takedown to a total hip arthroplasty-is it worth it? A systematic review.
Jauregui, Julio J; Kim, Joseph K; Shield, William P; Harb, Matthew; Illical, Emmanuel M; Adib, Farshad; Maheshwari, Aditya V
2017-08-01
Patients with surgically or spontaneously fused hips are often dissatisfied with their overall function and the debilitating effect on adjacent joints. Therefore, in properly selected patients, hip fusion-takedown and conversion to total hip arthroplasty (THA) can result in improved function and decreased pain. We aimed to (1) evaluate the indications for conversion, (2) evaluate the clinical outcomes, (3) analyze the overall complications, and (4) identify the overall satisfaction following the procedure. A systematic and comprehensive literature search was performed to analyze studies evaluating conversion of hip fusion to THA. After reviewing 3,882 studies, 27 total studies (1,104 hips) met our inclusion/exclusion criteria and were included in our final analysis. A weighted mean of rates was determined for each complication, including infection, instability, loosening, nerve-related, abductor-related, venous thrombotic event, and revision. The study population consisted of 53.2% male and 46.8% female subjects. The mean age at time of conversion was 52 years (range 36-65 years), the mean time until follow-up was 9.2 years (range 2.5-17.3), and the mean duration of arthrodesis was 27.7 years (range 11-40.2). As measured by Harris Hip Score, overall clinical outcomes improved from 58.1 points (range 42.4-70 points) pre-operatively to 80.0 (range 62-93.5) post-operatively. The specific complication rates were 5.3% (range 0-43.6%) for infection, 2.6% (range 0-15.4%) for instability, 6.2% (range 0-17.2%) for loosening, 4.7% (range 0-13%) for nerve-related complications, 13.1% (range 0-87%) for abductor-related complications, and 1.2% (range 0-13%) for venous thrombotic events. The revision rate was 12.0% (range 0-43.6%). Takedown of a fused-hip can be a challenging procedure. Although patients can benefit functionally, both patients and surgeons need to be aware of the complications and increased risk of further revision procedures, which should be an important part of the pre-operative discussion.
Lea, Mary-Anne; Bonadonna, Francesco; Hindell, Mark A; Guinet, Christophe; Goldsworthy, Simon D
2002-06-01
The estimation of milk consumption in free-ranging seals using tritium dilution techniques makes the key assumption that the animals drink no pre-formed water during the experimental period. However, frequent observations of unweaned Antarctic fur seal pups drinking water at Iles Kerguelen necessitated the testing of this assumption. We estimated water flux rates of 30 pups (10.7+/-0.3 kg) in four experimental groups by isotopic dilution over 4 days. The groups were: (1) pups held in an open air enclosure without access to water to estimate fasting metabolic water production (MWP); (2) free-ranging pups not administered additional water; (3) pups held in an open air enclosure and given a total of 300 ml of fresh water to verify technique accuracy; and (4) free-ranging pups given 200 ml of fresh water. Pups without access to water exhibited water flux rates (20.5+/-0.8 ml kg(-1)d(-1)), which were significantly lower than those observed for the free-ranging group (33.0+/-1.7 ml kg(-1) d(-1)). Mean estimated pre-formed water intake for the free-ranging experimental groups was 12.6 ml kg(-1) d(-1). Thus, MWP, measured as total water intake during fasting, may be significantly over-estimated in free-ranging Antarctic fur seal pups at Iles Kerguelen and at other sites and subsequently milk intake rates may be underestimated.
Gao, Yanxia; Ye, Chaoqun; Yang, Lingling; Wang, Tao
2016-01-01
Compared with chickens raised in intensively managed breeding farms, free-range chickens in China are quite popular due to lower breeding density and less antibiotics usage. However, investigations about Salmonella enterica from free-range chickens are quite rare. The aim of the present study was to investigate prevalence and characteristics of Salmonella in free-range chickens in Shandong province, China. During the period of August and November 2015, 300 fresh fecal swabs from different broilers in three free-range chicken farms (100 samples per farm) were collected to isolate Salmonella, and then these isolates were subjected to serotyping, antibiotic sensitivity testing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and multilocus sequence typing (ST). A total of 38 Salmonella isolates (38/300, 12.7%) were recovered. The most common serotype was Enteritidis (81.6%), followed by Indiana (13.2%) and Typhimurium (5.3%). Twenty-two out of 38 isolates (57.9%) were resistant to ampicillin, the highest resistance rate, but resistance rates to cefazolin, cefotaxime, and ceftazidime were only 7.9%. The multidrug resistance (MDR) rate was 26.3%. Additionally, the Salmonella isolates could be classified into 25 genotypes by ERIC-PCR and were divided into three ST types (ST11, ST17, and ST19), with ST11 the highest isolation rate (81.6%). In summary, as with other poultry, free-ranging chickens may also serve as potential reservoir for antibiotic resistant Salmonella, thereby posing a threat to public health. PMID:27800493
Zhao, Xiaonan; Gao, Yanxia; Ye, Chaoqun; Yang, Lingling; Wang, Tao; Chang, Weishan
2016-01-01
Compared with chickens raised in intensively managed breeding farms, free-range chickens in China are quite popular due to lower breeding density and less antibiotics usage. However, investigations about Salmonella enterica from free-range chickens are quite rare. The aim of the present study was to investigate prevalence and characteristics of Salmonella in free-range chickens in Shandong province, China. During the period of August and November 2015, 300 fresh fecal swabs from different broilers in three free-range chicken farms (100 samples per farm) were collected to isolate Salmonella , and then these isolates were subjected to serotyping, antibiotic sensitivity testing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and multilocus sequence typing (ST). A total of 38 Salmonella isolates (38/300, 12.7%) were recovered. The most common serotype was Enteritidis (81.6%), followed by Indiana (13.2%) and Typhimurium (5.3%). Twenty-two out of 38 isolates (57.9%) were resistant to ampicillin, the highest resistance rate, but resistance rates to cefazolin, cefotaxime, and ceftazidime were only 7.9%. The multidrug resistance (MDR) rate was 26.3%. Additionally, the Salmonella isolates could be classified into 25 genotypes by ERIC-PCR and were divided into three ST types (ST11, ST17, and ST19), with ST11 the highest isolation rate (81.6%). In summary, as with other poultry, free-ranging chickens may also serve as potential reservoir for antibiotic resistant Salmonella , thereby posing a threat to public health.
McCauley, Shannon J; Davis, Christopher J; Werner, Earl E; Robeson, Michael S
2014-07-01
Species' range sizes are shaped by fundamental differences in species' ecological and evolutionary characteristics, and understanding the mechanisms determining range size can shed light on the factors responsible for generating and structuring biological diversity. Moreover, because geographic range size is associated with a species' risk of extinction and their ability to respond to global changes in climate and land use, understanding these mechanisms has important conservation implications. Despite the hypotheses that dispersal behaviour is a strong determinant of species range areas, few data are available to directly compare the relationship between dispersal behaviour and range size. Here, we overcome this limitation by combining data from a multispecies dispersal experiment with additional species-level trait data that are commonly hypothesized to affect range size (e.g. niche breadth, local abundance and body size.). This enables us to examine the relationship between these species-level traits and range size across North America for fifteen dragonfly species. Ten models based on a priori predictions about the relationship between species traits and range size were evaluated and two models were identified as good predictors of species range size. These models indicated that only two species' level traits, dispersal behaviour and niche breadth were strongly related to range size. The evidence from these two models indicated that dragonfly species that disperse more often and further had larger North American ranges. Extinction and colonization dynamics are expected to be a key linkage between dispersal behaviour and range size in dragonflies. To evaluate how extinction and colonization dynamics among dragonflies were related to range size we used an independent data set of extinction and colonization rates for eleven dragonfly species and assessed the relationship between these populations rates and North American range areas for these species. We found a negative relationship between North American range size and species' extinction-to-colonization ratios. Our results indicate that metapopulation dynamics act to shape the extent of species' continental distributions. These population dynamics are likely to interact with dispersal behaviour, particularly at species range margins, to determine range limits and ultimately species range sizes. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.
Faster poleward range shifts in moths with more variable colour patterns
Forsman, Anders; Betzholtz, Per-Eric; Franzén, Markus
2016-01-01
Range shifts have been documented in many organisms, and climate change has been implicated as a contributing driver of latitudinal and altitudinal range modifications. However, little is known about what species trait(s) allow for faster environmental tracking and improved capacity for distribution expansions. We used data for 416 species of moths, and show that range limits in Sweden have shifted to the north by on average 52.4 km per decade between 1973 and 2014. When also including non-expanding species, average expansion rate was 23.2 km per decade. The rate of boundary shifts increased with increasing levels of inter-individual variation in colour patterns and decreased with increasing latitude. The association with colour patterns indicate that variation in this functionally important trait enables species to cope with novel and changing conditions. Northern range limits also increased with average abundance and decreased with increasing year-to-year abundance fluctuations, implicating production of dispersers as a driver of range dynamics. Studies of terrestrial animals show that rates of poleward shifts differ between taxonomic groups, increase over time, and depend on study duration and latitude. Knowledge of how distribution shifts change with time, location, and species characteristics may improve projections of responses to climate change and aid the protection of biodiversity. PMID:27808116
Faster poleward range shifts in moths with more variable colour patterns
NASA Astrophysics Data System (ADS)
Forsman, Anders; Betzholtz, Per-Eric; Franzén, Markus
2016-11-01
Range shifts have been documented in many organisms, and climate change has been implicated as a contributing driver of latitudinal and altitudinal range modifications. However, little is known about what species trait(s) allow for faster environmental tracking and improved capacity for distribution expansions. We used data for 416 species of moths, and show that range limits in Sweden have shifted to the north by on average 52.4 km per decade between 1973 and 2014. When also including non-expanding species, average expansion rate was 23.2 km per decade. The rate of boundary shifts increased with increasing levels of inter-individual variation in colour patterns and decreased with increasing latitude. The association with colour patterns indicate that variation in this functionally important trait enables species to cope with novel and changing conditions. Northern range limits also increased with average abundance and decreased with increasing year-to-year abundance fluctuations, implicating production of dispersers as a driver of range dynamics. Studies of terrestrial animals show that rates of poleward shifts differ between taxonomic groups, increase over time, and depend on study duration and latitude. Knowledge of how distribution shifts change with time, location, and species characteristics may improve projections of responses to climate change and aid the protection of biodiversity.
Patterns of sediment accumulation in the tidal marshes of Maine
Wood, M.E.; Kelley, J.T.; Belknap, D.F.
1989-01-01
One year's measurements of surficial sedimentation rates (1986-1987) for 26 Maine marsh sites were made over marker horizons of brick dust. Observed sediment accumulation rates, from 0 to 13 mm yr-1, were compared with marsh morphology, local relative sea-level rise rate, mean tidal range, and ice rafting activity. Marshes with four different morphologies (back-barrier, fluvial, bluff-toe, and transitional) showed distinctly different sediment accumulation rates. In general, back-barrier marshes had the highest accumulation rates and blufftoe marshes had the lowest rates, with intermediate values for transitional and fluvial marshes. No causal relationship between modern marsh sediment accumulation rate and relative sea-level rise rate (from tide gauge records) was observed. Marsh accretionary balance (sediment accumulation rate minus relative sea-level rise rate) did not correlate with mean tidal range for this meso- to macro-tidal area. Estimates of ice-rafted debris on marsh sites ranged from 0% to >100% of measured surficial sedimentation rates, indicating that ice transport of sediment may make a significant contribution to surficial sedimentation on Maine salt marshes. ?? 1989 Estuarine Research Federation.
Managing military training-related environmental disturbance.
Zentelis, Rick; Banks, Sam; Roberts, J Dale; Dovers, Stephen; Lindenmayer, David
2017-12-15
Military Training Areas (MTAs) cover at least 2 percent of the Earth's terrestrial surface and occur in all major biomes. These areas are potentially important for biodiversity conservation. The greatest challenge in managing MTAs is balancing the disturbance associated with military training and environmental values. These challenges are unique as no other land use is managed for these types of anthropogenic disturbances in a natural setting. We investigated how military training-related disturbance is best managed on MTAs. Specifically, we explored management options to maximise the amount of military training that can be undertaken on a MTA while minimising the amount of environmental disturbance. MTAs comprise of a number of ranges designed to facilitate different types of military training. We simulated military training-related environmental disturbance at different range usage rates under a typical range rotation use strategy, and compared the results to estimated ecosystem recovery rates from training activities. We found that even at relatively low simulated usage rates, random allocation and random spatial use of training ranges within an MTA resulted in environmental degradation under realistic ecological recovery rates. To avoid large scale environmental degradation, we developed a decision-making tool that details the best method for managing training-related disturbance by determining how training activities can be allocated to training ranges. Copyright © 2017 Elsevier Ltd. All rights reserved.
Short-range contacts govern the performance of industry-relevant battery cathodes
NASA Astrophysics Data System (ADS)
Morelly, Samantha L.; Alvarez, Nicolas J.; Tang, Maureen H.
2018-05-01
Fundamental understanding of how processing affects composite battery electrode structure and performance is still lacking, especially for industry-relevant electrodes with low fractions of inactive material. This work combines rheology, electronic conductivity measurements, and battery rate capability tests to prove that short-range electronic contacts are more important to cathode rate capability than either ion transport or long-range electronic conductivity. LiNi0.33Mn0.33Co0.33O2, carbon black, and polyvinylidene difluoride in 1-methyl-2-pyrrolidinone represent a typical commercial electrode with <5.5 wt% inactive material. Dry-mixing carbon black with active material decreases the relative fraction of bulk (free) carbon, as shown by small angle oscillatory shear and microscopy. More free carbon leads to a stronger gel network (more long-range particle contacts) and higher electronic conductivity of the dried films. Improvements in battery rate capability at constant electrode porosity do not correlate to electronic conductivity, but rather show an optimum fraction of free carbon. Simple comparison of rate capability in electrodes with increased total carbon loading (3 wt%) shows improvement for all fractions of free carbon. These results clearly indicate that ion transport cannot be limiting and highlight the critical importance of short-range electronic contacts for controlling battery performance.
Normal modes of weak colloidal gels
NASA Astrophysics Data System (ADS)
Varga, Zsigmond; Swan, James W.
2018-01-01
The normal modes and relaxation rates of weak colloidal gels are investigated in calculations using different models of the hydrodynamic interactions between suspended particles. The relaxation spectrum is computed for freely draining, Rotne-Prager-Yamakawa, and accelerated Stokesian dynamics approximations of the hydrodynamic mobility in a normal mode analysis of a harmonic network representing several colloidal gels. We find that the density of states and spatial structure of the normal modes are fundamentally altered by long-ranged hydrodynamic coupling among the particles. Short-ranged coupling due to hydrodynamic lubrication affects only the relaxation rates of short-wavelength modes. Hydrodynamic models accounting for long-ranged coupling exhibit a microscopic relaxation rate for each normal mode, λ that scales as l-2, where l is the spatial correlation length of the normal mode. For the freely draining approximation, which neglects long-ranged coupling, the microscopic relaxation rate scales as l-γ, where γ varies between three and two with increasing particle volume fraction. A simple phenomenological model of the internal elastic response to normal mode fluctuations is developed, which shows that long-ranged hydrodynamic interactions play a central role in the viscoelasticity of the gel network. Dynamic simulations of hard spheres that gel in response to short-ranged depletion attractions are used to test the applicability of the density of states predictions. For particle concentrations up to 30% by volume, the power law decay of the relaxation modulus in simulations accounting for long-ranged hydrodynamic interactions agrees with predictions generated by the density of states of the corresponding harmonic networks as well as experimental measurements. For higher volume fractions, excluded volume interactions dominate the stress response, and the prediction from the harmonic network density of states fails. Analogous to the Zimm model in polymer physics, our results indicate that long-ranged hydrodynamic interactions play a crucial role in determining the microscopic dynamics and macroscopic properties of weak colloidal gels.
Cho, Sung M; Moazami, Nader; Frontera, Jennifer A
2017-08-01
Ischemic stroke and intracranial hemorrhage (ICH) following left ventricular assist device (LVAD) placement are major causes of morbidity. The incidence and mortality associated with these events stratified by device type have not been systematically explored. A systematic review of PubMed was conducted from January 2007 through June 2016 for all English-language articles involving HeartMate II (HMII) and HeartWare LVAD patients. Ischemic stroke and/or ICH incidence (events per patient-year) and associated mortality rates were abstracted for each device type. Of 735 articles reviewed, 48 (11,310 patients) met inclusion criteria (33 HMII, six HeartWare, eight both devices, and one unspecified). The median duration of device support was 112 days (total 13,723 patient-years). Overall, ischemic stroke or ICH occurred in 9.8% (1110 persons and 0.08 events per patient year [EPPY]). Ischemic stroke occurred in a median of 6.0% or 0.06 EPPY (range 0-16% or 0-0.21 EPPY) of HMII patients versus 7.5% or 0.09 EPPY (range 4-17.1% or 0.01-0.94 EPPY) of HeartWare patients. ICH occurred in a median of 3.0% or 0.04 EPPY (range 0-13.5% or 0-0.13 EPPY) of HMII and 8.0% or 0.08 EPPY (range 3-23% or 0.01-0.56 EPPY) of HeartWare patients. The median mortality rate for LVAD-associated ischemic stroke was 31% (HMII: 33%, [range 2.4-75%] and HeartWare: 11.5% [range 3.9-40%]), and the median mortality rate following ICH was 71% (HMII: 75%, [range 3.9-100%] and HeartWare: 44%, [range 3.1-88%]). Ischemic stroke and ICH are common after LVAD placement, but heterogeneous event rates are reported in the literature. Given the high associated mortality, further prospective study is warranted.
OBSERVATIONAL LIMITS ON TYPE 1 ACTIVE GALACTIC NUCLEUS ACCRETION RATE IN COSMOS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trump, Jonathan R.; Impey, Chris D.; Gabor, Jared
2009-07-20
We present black hole masses and accretion rates for 182 Type 1 active galactic nuclei (AGNs) in COSMOS. We estimate masses using the scaling relations for the broad H {beta}, Mg II, and C IV emission lines in the redshift ranges 0.16 < z < 0.88, 1 < z < 2.4, and 2.7 < z < 4.9. We estimate the accretion rate using an Eddington ratio L{sub I}/L{sub Edd} estimated from optical and X-ray data. We find that very few Type 1 AGNs accrete below L{sub I} /L{sub Edd} {approx} 0.01, despite simulations of synthetic spectra which show that themore » survey is sensitive to such Type 1 AGNs. At lower accretion rates the broad-line region may become obscured, diluted, or nonexistent. We find evidence that Type 1 AGNs at higher accretion rates have higher optical luminosities, as more of their emission comes from the cool (optical) accretion disk with respect to shorter wavelengths. We measure a larger range in accretion rate than previous works, suggesting that COSMOS is more efficient at finding low accretion rate Type 1 AGNs. However, the measured range in accretion rate is still comparable to the intrinsic scatter from the scaling relations, suggesting that Type 1 AGNs accrete at a narrow range of Eddington ratio, with L{sub I} /L{sub Edd} {approx} 0.1.« less
Dose rate mapping of VMAT treatments
NASA Astrophysics Data System (ADS)
Podesta, Mark; Antoniu Popescu, I.; Verhaegen, Frank
2016-06-01
Human tissues exhibit a varying response to radiation dose depending on the dose rate and fractionation scheme used. Dose rate effects have been reported for different radiations, and tissue types. The literature indicates that there is not a significant difference in response for low-LET radiation when using dose rates between 1 Gy min-1 and 12 Gy min-1 but lower dose rates have an observable sparing effect on tissues and a differential effect between tissues. In intensity-modulated radiotherapy such as volumetric modulated arc therapy (VMAT) the dose can be delivered with a wide range of dose rates. In this work we developed a method based on time-resolved Monte Carlo simulations to quantify the dose rate frequency distribution for clinical VMAT treatments for three cancer sites, head and neck, lung, and pelvis within both planning target volumes (PTV) and normal tissues. The results show a wide range of dose rates are used to deliver dose in VMAT and up to 75% of the PTV can have its dose delivered with dose rates <1 Gy min-1. Pelvic plans on average have a lower mean dose rate within the PTV than lung or head and neck plans but a comparable mean dose rate within the organs at risk. Two VMAT plans that fulfil the same dose objectives and constraints may be delivered with different dose rate distributions, particularly when comparing single arcs to multiple arc plans. It is concluded that for dynamic plans, the dose rate range used varies to a larger degree than previously assumed. The effect of the dose rate range in VMAT on clinical outcome is unknown.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Pay range. 534.502 Section 534.502 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PAY UNDER OTHER SYSTEMS Pay for Senior-Level and Scientific and Professional Positions § 534.502 Pay range. A pay rate fixed under this...
25 CFR 161.204 - How are carrying capacities and stocking rates established?
Code of Federal Regulations, 2010 CFR
2010-04-01
... be based on forage production, range utilization, the application of land management practices, and range improvements in place to achieve uniformity of grazing under sustained yield management principles... agricultural resource management plan and range unit management plan. (b) BIA, with the concurrence of the...
Tectonic uplift, threshold hillslopes, and denudation rates in a developing mountain range
Binnie, S.A.; Phillips, W.M.; Summerfield, M.A.; Fifield, L.K.
2007-01-01
Studies across a broad range of drainage basins have established a positive correlation between mean slope gradient and denudation rates. It has been suggested, however, that this relationship breaks down for catchments where slopes are at their threshold angle of stability because, in such cases, denudation is controlled by the rate of tectonic uplift through the rate of channel incision and frequency of slope failure. This mechanism is evaluated for the San Bernardino Mountains, California, a nascent range that incorporates both threshold hill-slopes and remnants of pre-uplift topography. Concentrations of in situ-produced cosmogenic 10Be in alluvial sediments are used to quantify catchment-wide denudation rates and show a broadly linear relationship with mean slope gradient up to ???30??: above this value denudation rates vary substantially for similar mean slope gradients. We propose that this decoupling in the slope gradient-denudation rate relationship marks the emergence of threshold topography and coincides with the transition from transport-limited to detachment-limited denudation. The survival in the San Bernardino Mountains of surfaces formed prior to uplift provides information on the topographic evolution of the range, in particular the transition from slope-gradient-dependent rates of denudation to a regime where denudation rates are controlled by rates of tectonic uplift. This type of transition may represent a general model for the denudational response to orogenic uplift and topographic evolution during the early stages of mountain building. ?? 2007 The Geological Society of America.
Kinetics of the reaction of Cl atoms with CHCl 3 over the temperature range 253-313 K
NASA Astrophysics Data System (ADS)
Nilsson, Elna J. K.; Hoff, Janus; Nielsen, Ole John; Johnson, Matthew S.
2010-07-01
The reaction CHCl 3 + Cl → CCl 3 + HCl was studied in the atmospherically relevant temperature range from 253 to 313 K and in 930 mbar of N 2 diluent using the relative rate method. A temperature dependent reaction rate constant, valid in the temperature range 220-330 K, was determined by a fit to the result of the present study and that of Orlando (1999); k = (3.77 ± 0.32) × 10 -12 exp((-1011 ± 24)/T) cm 3 molecule -1 s -1.
Inter-physician agreement on the readiness of sick-listed employees to return to work.
Schreuder, Jolanda A H; Roelen, Corné A M; de Boer, Mintje; Brouwer, Sandra; Groothoff, Johan W
2012-01-01
To determine the agreement between occupational physician (OP) ratings of an employee's readiness to return to work (RRTW). Anonymized written vignettes of 132 employees, sick-listed for at least 3 weeks, were reviewed by 5 OPs. The OPs intuitively rated RRTW as the ability (knowledge and skills) and willingness (motivation and confidence) of sick-listed employees to resume work. Inter-OP percentages of agreement were calculated and Cohen's kappas (κ) were determined to correct for agreement by chance. The percentage of agreement between OPs was 57% (range 39-89%) on the ability and 63% (range 48-87%) on the willingness of sick-listed employees to resume work. The mean κ was 0.14 (range from -0.21 to 0.79) for ability and 0.25 (range from -0.11 to 0.74) for willingness. The OP-rating of RRTW of employees sick-listed with mental disorders did not differ from the OP-rating of RRTW of employees with musculoskeletal disorders. The inter-OP agreement on intuitively rated RRTW showed a wide variability, which accentuates the need for instruments to establish an employee's RRTW and for training in giving well founded return to work recommendations.
Basic statistical analyses of candidate nickel-hydrogen cells for the Space Station Freedom
NASA Technical Reports Server (NTRS)
Maloney, Thomas M.; Frate, David T.
1993-01-01
Nickel-Hydrogen (Ni/H2) secondary batteries will be implemented as a power source for the Space Station Freedom as well as for other NASA missions. Consequently, characterization tests of Ni/H2 cells from Eagle-Picher, Whittaker-Yardney, and Hughes were completed at the NASA Lewis Research Center. Watt-hour efficiencies of each Ni/H2 cell were measured for regulated charge and discharge cycles as a function of temperature, charge rate, discharge rate, and state of charge. Temperatures ranged from -5 C to 30 C, charge rates ranged from C/10 to 1C, discharge rates ranged from C/10 to 2C, and states of charge ranged from 20 percent to 100 percent. Results from regression analyses and analyses of mean watt-hour efficiencies demonstrated that overall performance was best at temperatures between 10 C and 20 C while the discharge rate correlated most strongly with watt-hour efficiency. In general, the cell with back-to-back electrode arrangement, single stack, 26 percent KOH, and serrated zircar separator and the cell with a recirculating electrode arrangement, unit stack, 31 percent KOH, zircar separators performed best.
Evaluation of trapping-web designs
Lukacs, P.M.; Anderson, D.R.; Burnham, K.P.
2005-01-01
The trapping web is a method for estimating the density and abundance of animal populations. A Monte Carlo simulation study is performed to explore performance of the trapping web for estimating animal density under a variety of web designs and animal behaviours. The trapping performs well when animals have home ranges, even if the home ranges are large relative to trap spacing. Webs should contain at least 90 traps. Trapping should continue for 5-7 occasions. Movement rates have little impact on density estimates when animals are confined to home ranges. Estimation is poor when animals do not have home ranges and movement rates are rapid. The trapping web is useful for estimating the density of animals that are hard to detect and occur at potentially low densities. ?? CSIRO 2005.
Sander, Uwe; Kolb, Benjamin; Taheri, Fatemeh; Patzelt, Christiane; Emmert, Martin
2017-11-01
The effect of public reporting to improve quality in healthcare is reduced by the limited intelligibility of information about the quality of healthcare providers. This may result in worse health-related choices especially for older people and those with lower levels of education. There is, as yet, little information as to whether laymen understand the concepts behind quality comparisons and if this comprehension is correlated with hospital choices. An instrument with 20 items was developed to analyze the intelligibility of five technical terms which were used in German hospital report cards to explain risk-adjusted death rates. Two online presentations of risk-adjusted death rates for five hospitals in the style of hospital report cards were developed. An online survey of 353 volunteers tested the comprehension of the risk-adjusted mortality rates and included an experimental hospital choice. The intelligibility of five technical terms was tested: risk-adjusted, actual and expected death rate, reference range and national average. The percentages of correct answers for the five technical terms were in the range of 75.0-60.2%. Between 23.8% and 5.1% of the respondents were not able to answer the question about the technical term itself. The least comprehensible technical terms were "risk-adjusted death rate" and "reference range". The intelligibility of the 20 items that were used to test the comprehension of the risk-adjusted mortality was between 89.5% and 14.2%. The two items that proved to be least comprehensible were related to the technical terms "risk-adjusted death rate" and "reference range". For all five technical terms it was found that a better comprehension correlated significantly with better hospital choices. We found a better than average intelligibility for the technical terms "actual and expected death rate" and for "national average". The least understandable were "risk-adjusted death rate" and "reference range". Since the self-explanatory technical terms "actual and expected death rate" and "national average" are easy to understand and the comprehension is correlated with hospitals choices, we recommend using them for the presentation of measures which contain risk-adjusted mortality. The technical terms "risk-adjusted death rate" and "reference range" should stay in the background, since comprehension problems can be expected and explanations would have to be provided. Copyright © 2017. Published by Elsevier GmbH.
Precise orbit determination of the Lunar Reconnaissance Orbiter and first gravity field results
NASA Astrophysics Data System (ADS)
Maier, Andrea; Baur, Oliver
2014-05-01
The Lunar Reconnaissance Orbiter (LRO) was launched in 2009 and is expected to orbit the Moon until the end of 2014. Among other instruments, LRO has a highly precise altimeter on board demanding an orbit accuracy of one meter in the radial component. Precise orbit determination (POD) is achieved with radiometric observations (Doppler range rates, ranges) on the one hand, and optical laser ranges on the other hand. LRO is the first satellite at a distance of approximately 360 000 to 400 000 km from the Earth that is routinely tracked with optical laser ranges. This measurement type was introduced to achieve orbits of higher precision than it would be possible with radiometric observations only. In this contribution we investigate the strength of each measurement type (radiometric range rates, radiometric ranges, optical laser ranges) based on single-technique orbit estimation. In a next step all measurement types are combined in a joined analysis. In addition to POD results, preliminary gravity field coefficients are presented being a subsequent product of the orbit determination process. POD and gravity field estimation was accomplished with the NASA/GSFC software packages GEODYN and SOLVE.
24 CFR 3280.805 - Branch circuits required.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., water heater, range, and central or room air conditioner, etc.). There shall be one or more circuits of... outlets, the sum of rated amperes shall not exceed the branch-circuit rating. Motor loads or other... specified for ranges in § 3280.811(a)(5). For central air conditioning, see Article 440 of the National...
Alternative Pathways in Family Child Care Quality Rating and Improvement Systems
ERIC Educational Resources Information Center
Kelton, Robyn E.; Talan, Teri N.; Bloom, Paula J.
2013-01-01
As research continues to underscore the positive impact high-quality early childhood programs have on young children, numerous states have implemented quality rating and improvement systems (QRIS) to measure and improve the services young children receive across a wide range of early learning settings. These state systems range from two to five…
Lengthening by distraction osteogenesis in congenital shortening of metacarpals.
Bulut, Mehmet; Uçar, Bekir Yavuz; Azboy, Ibrahim; Belhan, Oktay; Yilmaz, Erhan; Karakurt, Lokman
2013-01-01
The aim of this study was to present the results of seven cases of metacarpal lengthening by distraction osteogenesis and to discuss the ideal daily rate of distraction. Metacarpal lengthening was performed by distraction osteogenesis in the seven metacarpals of four patients (3 females, 1 male; mean age: 14.9 years). A unilateral external fixator was used for lengthening. Lengthening was initiated with a distraction rate of 2x0.5 mm/day in the patient with bilateral involvement of the middle and ring metacarpals. On the tenth day of lengthening, distraction was discontinued due to pain and contracture. Then, distraction was continued with a rate of 2x0.25 mm/day. In all other cases, the distraction rate was 0.5 mm/day. Pre- and postoperative range of motion was measured with a goniometer. Patient satisfaction was evaluated with visual analog scale. The mean pre- and postoperative metacarpal lengths were 34.6 mm (range: 33 to 37) and 49.7 mm (range: 47 to 52), respectively. The mean lengthening achieved was 15.1 mm (range: 14 to 17), while the mean distraction rate was 0.55 mm/day (range: 0.48 to 0.63). No functional loss was observed in the fingers at the final check-up. The patients were happy with the functional and cosmetic results. Distraction osteogenesis is a safe method providing acceptable cosmetic and functional results in patients with congenital metacarpal shortness. The length of metacarpals and muscles that will be affected from lengthening should be considered when determining the daily rate of distraction.
Demographic Responses To Climate Manipulations Across a Species Range
NASA Astrophysics Data System (ADS)
Oldfather, M. F.
2016-12-01
Species biogeographic responses to climate change will occur through the local extinction and establishment of populations. The overall performance of populations across a species range is shaped by the idiosyncratic sensitivities of demographic rates to the changing climate conditions. Heterogeneous topography partially decouples temperature and soil moisture presenting an opportunity to disentangle demographic sensitivity to multiple local climate variables and refine range shift predictions in response to complex climate change. Since 2013, I have monitored 16 populations of a long-lived alpine plant, Ivesia lycopodioides var. scandularis (Rosaceae) across the entirety of its altitudinal range in the arid White Mountains, CA (3350 - 4420m). I quantified microclimatic soil moisture and temperature, and the demographic rates of over 4,000 individuals. Demographic rates exhibited sensitivity to accumulated degree-days (ex. reproduction), soil volumetric water content (ex. germination), or the interaction between these climate variables (ex. survival). These observations motivated an experimental test of the relationship between demography and local climate with manipulations of increased summertime temperature and precipitation in nine populations. All demographic rates were sensitive to the climate manipulations and the magnitude of the demographic response depended on the population's location within the range. However, the modeled population growth rate was only minimally affected by the manipulations in most populations. The inverse responses of many of the demographic rates may allow populations to demographically buffer against the climate manipulations. However, in one low elevation edge population the negative effect of heating on survival overwhelmed the positive effect on germination, indicating that the capacity of populations to demographically buffer may have a limit.
NASA Astrophysics Data System (ADS)
Pu, Enxiang; Zheng, Wenjie; Song, Zhigang; Feng, Han; Zhu, Yuliang
2017-03-01
Hot deformation behavior of a Fe-24Cr-22Ni-7Mo-0.5N superaustenitic stainless steel was investigated by hot compression tests in a wide temperature range of 950-1250 °C and strain rate range of 0.001-10 s-1. The flow curves show that the flow stress decreases as the deformation temperature increases or the strain rate decreases. The processing maps developed on the basis of the dynamic materials model and flow stress data were adopted to optimize the parameters of hot working. It was found that the strain higher than 0.2 has no significant effect on the processing maps. The optimum processing conditions were in the temperature range of 1125-1220 °C and strain rate range of 0.1-3 s-1. Comparing to other stable domains, microstructural observations in this domain revealed the complete dynamic recrystallization (DRX) with finer and more uniform grain size. Flow instability occurred in the domain of temperature lower than 1100 °C and strain rate higher than 0.1 s-1.
Long-Term Results of Brachytherapy for Carcinoma of the Penis Confined to the Glans (N- or NX)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crevoisier, Renaud de; Slimane, Khemais; Sanfilippo, Nicholas
2009-07-15
Purpose: To analyze the results of exclusive interstitial low-dose-rate brachytherapy (BT) for squamous cell carcinoma (SCC) of the penis, strictly confined to the glans. Methods and Materials: A total of 144 patients with SSC of the glans penis were treated with BT. Inguinal nodal dissection was performed in 19% of patients (all N-). After circumcision, BT was performed using the hypodermic needle technique. Median iridium length per patients was 24 cm (range, 4-108) and median dose was 65 Gy (range, 37-75). Median treated volume was 22 cm{sup 3} (range, 5-110) and median reference isodose rate was 0.4 Gy/h (range, 0.2-1.2).more » Results: Median follow-up was 5.7 years (range, 0.5-29). The 10-year penile recurrence, inguinal lymph node recurrence, and inguinal nodal metastasis rates were: 20% (CI 95%, 11-29), 11% (CI 95%, 5-17), and 6% (CI 95%, 2-10), respectively. After salvage treatment, 86% patients with local failure were in a complete remission at last follow-up. The 10-year probability of avoiding penile surgery (for complication or local recurrence) was 72% (CI 95%, 62-82). The 10-year cancer-specific survival rate was 92% (CI 95%, 87-97). Diameter of tumor significantly increased the risk of recurrence (p = 0.02). The 10-year painful ulceration and stenosis risk rates were: 26% (CI 95%, 17-35) and 29% (CI 95%, 18-40), respectively. Seven patients required excision for necrosis. Treated volume and reference isodose rate significantly increased the risk of complications. Conclusion: BT is an effective conservative treatment for SCC confined to the glans. Salvage local treatment is effective. Dose rate should be limited to decrease toxicity.« less
Fossil preservation and the stratigraphic ranges of taxa
NASA Technical Reports Server (NTRS)
Foote, M.; Raup, D. M.
1996-01-01
The incompleteness of the fossil record hinders the inference of evolutionary rates and patterns. Here, we derive relationships among true taxonomic durations, preservation probability, and observed taxonomic ranges. We use these relationships to estimate original distributions of taxonomic durations, preservation probability, and completeness (proportion of taxa preserved), given only the observed ranges. No data on occurrences within the ranges of taxa are required. When preservation is random and the original distribution of durations is exponential, the inference of durations, preservability, and completeness is exact. However, reasonable approximations are possible given non-exponential duration distributions and temporal and taxonomic variation in preservability. Thus, the approaches we describe have great potential in studies of taphonomy, evolutionary rates and patterns, and genealogy. Analyses of Upper Cambrian-Lower Ordovician trilobite species, Paleozoic crinoid genera, Jurassic bivalve species, and Cenozoic mammal species yield the following results: (1) The preservation probability inferred from stratigraphic ranges alone agrees with that inferred from the analysis of stratigraphic gaps when data on the latter are available. (2) Whereas median durations based on simple tabulations of observed ranges are biased by stratigraphic resolution, our estimates of median duration, extinction rate, and completeness are not biased.(3) The shorter geologic ranges of mammalian species relative to those of bivalves cannot be attributed to a difference in preservation potential. However, we cannot rule out the contribution of taxonomic practice to this difference. (4) In the groups studied, completeness (proportion of species [trilobites, bivalves, mammals] or genera [crinoids] preserved) ranges from 60% to 90%. The higher estimates of completeness at smaller geographic scales support previous suggestions that the incompleteness of the fossil record reflects loss of fossiliferous rock more than failure of species to enter the fossil record in the first place.
Microsurgery Workout: A Novel Simulation Training Curriculum Based on Nonliving Models.
Rodriguez, Jose R; Yañez, Ricardo; Cifuentes, Ignacio; Varas, Julian; Dagnino, Bruno
2016-10-01
Currently, there are no valid training programs based solely on nonliving models. The authors aimed to develop and validate a microsurgery training program based on nonliving models and assess the transfer of skills to a live rat model. Postgraduate year-3 general surgery residents were assessed in a 17-session program, performing arterial and venous end-to-end anastomosis on ex vivo chicken models. Procedures were recorded and rated by two blinded experts using validated global and specific scales (objective structured assessment of technical skills) and a validated checklist. Operating times and patency rates were assessed. Hand-motion analysis was used to measure economy of movements. After training, residents performed an arterial and venous end-to-end anastomosis on live rats. Results were compared to six experienced surgeons in the same models. Values of p < 0.05 were considered statistically significant. Learning curves were achieved. Ten residents improved their median global and specific objective structured assessment of technical skills scores for artery [10 (range, 8 to 10) versus 28 (range, 27 to 29), p < 0.05; and 8 (range, 7 to 9) versus 28 (range, 27 to 28), p < 0.05] and vein [8 (range, 8 to 11) versus 28 (range, 27 to 28), p < 0.05; and 8 (range, 7 to 9) versus 28 (range, 27 to 29), p < 0.05]. Checklist scores also improved for both procedures (p < 0.05). Trainees were slower and less efficient than experienced surgeons (p < 0.05). In the living rat, patency rates at 30 minutes were 100 percent and 50 percent for artery and vein, respectively. Significant acquisition of microsurgical skills was achieved by trainees to a level similar to that of experienced surgeons. Acquired skills were transferred to a more complex live model.
Heart rate reveals torpor at high body temperatures in lowland tropical free-tailed bats.
O'Mara, M Teague; Rikker, Sebastian; Wikelski, Martin; Ter Maat, Andries; Pollock, Henry S; Dechmann, Dina K N
2017-12-01
Reduction in metabolic rate and body temperature is a common strategy for small endotherms to save energy. The daily reduction in metabolic rate and heterothermy, or torpor, is particularly pronounced in regions with a large variation in daily ambient temperature. This applies most strongly in temperate bat species (order Chiroptera), but it is less clear how tropical bats save energy if ambient temperatures remain high. However, many subtropical and tropical species use some daily heterothermy on cool days. We recorded the heart rate and the body temperature of free-ranging Pallas' mastiff bats ( Molossus molossus ) in Gamboa, Panamá, and showed that these individuals have low field metabolic rates across a wide range of body temperatures that conform to high ambient temperature. Importantly, low metabolic rates in controlled respirometry trials were best predicted by heart rate, and not body temperature . Molossus molossus enter torpor-like states characterized by low metabolic rate and heart rates at body temperatures of 32°C, and thermoconform across a range of temperatures. Flexible metabolic strategies may be far more common in tropical endotherms than currently known.
The strain-rate sensitivity of high-strength high-toughness steels.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dilmore, M.F.; Crenshaw, Thomas B.; Boyce, Brad Lee
2006-01-01
The present study examines the strain-rate sensitivity of four high strength, high-toughness alloys at strain rates ranging from 0.0002 s-1 to 200 s-1: Aermet 100, a modified 4340, modified HP9-4-20, and a recently developed Eglin AFB steel alloy, ES-1c. A refined dynamic servohydraulic method was used to perform tensile tests over this entire range. Each of these alloys exhibit only modest strain-rate sensitivity. Specifically, the strain-rate sensitivity exponent m, is found to be in the range of 0.004-0.007 depending on the alloy. This corresponds to a {approx}10% increase in the yield strength over the 7-orders of magnitude change in strain-rate.more » Interestingly, while three of the alloys showed a concominant {approx}3-10% drop in their ductility with increasing strain-rate, the ES1-c alloy actually exhibited a 25% increase in ductility with increasing strain-rate. Fractography suggests the possibility that at higher strain-rates ES-1c evolves towards a more ductile dimple fracture mode associated with microvoid coalescence.« less
Heart rate reveals torpor at high body temperatures in lowland tropical free-tailed bats
Rikker, Sebastian; Wikelski, Martin; Ter Maat, Andries
2017-01-01
Reduction in metabolic rate and body temperature is a common strategy for small endotherms to save energy. The daily reduction in metabolic rate and heterothermy, or torpor, is particularly pronounced in regions with a large variation in daily ambient temperature. This applies most strongly in temperate bat species (order Chiroptera), but it is less clear how tropical bats save energy if ambient temperatures remain high. However, many subtropical and tropical species use some daily heterothermy on cool days. We recorded the heart rate and the body temperature of free-ranging Pallas' mastiff bats (Molossus molossus) in Gamboa, Panamá, and showed that these individuals have low field metabolic rates across a wide range of body temperatures that conform to high ambient temperature. Importantly, low metabolic rates in controlled respirometry trials were best predicted by heart rate, and not body temperature. Molossus molossus enter torpor-like states characterized by low metabolic rate and heart rates at body temperatures of 32°C, and thermoconform across a range of temperatures. Flexible metabolic strategies may be far more common in tropical endotherms than currently known. PMID:29308259
Osteo-odonto keratoprosthesis: systematic review of surgical outcomes and complication rates.
Tan, Anna; Tan, Donald T; Tan, Xiao-Wei; Mehta, Jodhbir S
2012-01-01
Case series on osteo-odonto keratoprosthesis (OOKP) published in English from 1950-June 2010 were identified in Medline/PubMed. Indications for surgery, visual acuity, anatomical survival, complication and repeat surgery rates were compared among the different studies. Our own case series is a retrospective review of all OOKP surgeries performed in our center from February 2004-July 2011. Eight case series including our own were systematically reviewed. Sample sizes ranged from 4-181 eyes. The most common indications for surgery were severe cases of Stevens-Johnson syndrome and thermal and chemical burns that were unamenable to other forms of surgery or had had previous surgical failure. Anatomical survival rate in all the studies was 87.8% (range 67-100%) at 5 years, and three studies showed survival rates of 81.0% (range 65-98%) at 20 years. Visual acuity was more than 6/18 in 52% (range 46-72%) of the eyes with OOKP surgery. The most common intraoperative complication was vitreous hemorrhage (0-52%) and the most common long-term blinding complication was glaucoma (7-47%). Endophthalmitis rates ranged from 2-8%. The most common repeat surgical procedure was mucosal trimming due to mucosal overgrowth at the optical cylinder and mucosal grafting for extrusion of the OOKP or mucosal ulceration. Of the available biological and synthetic keratoprosthesis, OOKP appears to be an excellent option for the treatment of end-stage corneal diseases. Copyright © 2012 Elsevier Inc. All rights reserved.
Manuel, Marin; Heckman, C J
2011-10-19
Classical studies of the mammalian neuromuscular system have shown an impressive adaptation match between the intrinsic properties of motoneurons and the contractile properties of their motor units. In these studies, the rate at which motoneurons start to fire repetitively corresponds to the rate at which individual twitches start to sum, and the firing rate increases linearly with the amount of excitation ("primary range") up to the point where the motor unit develops its maximal force. This allows for the gradation of the force produced by a motor unit by rate modulation. In adult mouse motoneurons, however, we recently described a regime of firing ("subprimary range") that appears at lower excitation than what is required for the primary range, a finding that might challenge the classical conception. To investigate the force production of mouse motor units, we simultaneously recorded, for the first time, the motoneuron discharge elicited by intracellular ramps of current and the force developed by its motor unit. We showed that the motor unit developed nearly its maximal force during the subprimary range. This was found to be the case regardless of the input resistance of the motoneuron, the contraction speed, or the tetanic force of the motor unit. Our work suggests that force modulation in small mammals mainly relies on the number of motor units that are recruited rather than on rate modulation of individual motor units.
Grigg, G C; Seebacher, F
1999-01-01
The discovery that changes in heart rate and blood flow allow some reptiles to heat faster than they cool has become a central paradigm in our understanding of reptilian thermoregulation. However, this hysteresis in heart rate has been demonstrated only in simplistic laboratory heating and cooling trials, leaving its functional significance in free-ranging animals unproven. To test the validity of this paradigm, we measured heart rate and body temperature (Tb) in undisturbed, free-ranging bearded dragons (Pogona barbata), the species in which this phenomenon was first described. Our field data confirmed the paradigm and we found that heart rate during heating usually exceeded heart rate during cooling at any Tb. Importantly, however, we discovered that heart rate was proportionally faster in cool lizards whose Tb was still well below the 'preferred Tb range' compared to lizards whose Tb was already close to it. Similarly, heart rate during cooling was proportionally slower the warmer the lizard and the greater its cooling potential compared to lizards whose Tb was already near minimum operative temperature. Further, we predicted that, if heart rate hysteresis has functional significance, a 'reverse hysteresis' pattern should be observable when lizards risked overheating. This was indeed the case and, during heating on those occasions when Tb reached very high levels (> 40 degrees C), heart rate was significantly lower than heart rate during the immediately following cooling phase. These results demonstrate that physiological control of thermoregulation in reptiles is more complex than has been previously recognized. PMID:10418165
Target recognition for ladar range image using slice image
NASA Astrophysics Data System (ADS)
Xia, Wenze; Han, Shaokun; Wang, Liang
2015-12-01
A shape descriptor and a complete shape-based recognition system using slice images as geometric feature descriptor for ladar range images are introduced. A slice image is a two-dimensional image generated by three-dimensional Hough transform and the corresponding mathematical transformation. The system consists of two processes, the model library construction and recognition. In the model library construction process, a series of range images are obtained after the model object is sampled at preset attitude angles. Then, all the range images are converted into slice images. The number of slice images is reduced by clustering analysis and finding a representation to reduce the size of the model library. In the recognition process, the slice image of the scene is compared with the slice image in the model library. The recognition results depend on the comparison. Simulated ladar range images are used to analyze the recognition and misjudgment rates, and comparison between the slice image representation method and moment invariants representation method is performed. The experimental results show that whether in conditions without noise or with ladar noise, the system has a high recognition rate and low misjudgment rate. The comparison experiment demonstrates that the slice image has better representation ability than moment invariants.
NASA Astrophysics Data System (ADS)
Li, Xin; Song, Weiying; Yang, Kai; Krishnan, N. M. Anoop; Wang, Bu; Smedskjaer, Morten M.; Mauro, John C.; Sant, Gaurav; Balonis, Magdalena; Bauchy, Mathieu
2017-08-01
Although molecular dynamics (MD) simulations are commonly used to predict the structure and properties of glasses, they are intrinsically limited to short time scales, necessitating the use of fast cooling rates. It is therefore challenging to compare results from MD simulations to experimental results for glasses cooled on typical laboratory time scales. Based on MD simulations of a sodium silicate glass with varying cooling rate (from 0.01 to 100 K/ps), here we show that thermal history primarily affects the medium-range order structure, while the short-range order is largely unaffected over the range of cooling rates simulated. This results in a decoupling between the enthalpy and volume relaxation functions, where the enthalpy quickly plateaus as the cooling rate decreases, whereas density exhibits a slower relaxation. Finally, we show that, using the proper extrapolation method, the outcomes of MD simulations can be meaningfully compared to experimental values when extrapolated to slower cooling rates.
Ice nucleation rates near ˜225 K
NASA Astrophysics Data System (ADS)
Amaya, Andrew J.; Wyslouzil, Barbara E.
2018-02-01
We have measured the ice nucleation rates, Jice, in supercooled nano-droplets with radii ranging from 6.6 nm to 10 nm and droplet temperatures, Td, ranging from 225 K to 204 K. The initial temperature of the 10 nm water droplets is ˜250 K, i.e., well above the homogeneous nucleation temperature for micron sized water droplets, TH ˜235 K. The nucleation rates increase systematically from ˜1021 cm-3 s-1 to ˜1022 cm-3 s-1 in this temperature range, overlap with the nucleation rates of Manka et al. [Phys. Chem. Chem. Phys. 14, 4505 (2012)], and suggest that experiments with larger droplets would extrapolate smoothly the rates of Hagen et al. [J. Atmos. Sci. 38, 1236 (1981)]. The sharp corner in the rate data as temperature drops is, however, difficult to match with available theory even if we correct classical nucleation theory and the physical properties of water for the high internal pressure of the nanodroplets.
Examining the relationship between local extinction risk and position in range.
Boakes, Elizabeth H; Isaac, Nicholas J B; Fuller, Richard A; Mace, Georgina M; McGowan, Philip J K
2018-02-01
Over half of globally threatened animal species have experienced rapid geographic range loss. Identifying the parts of species' distributions most vulnerable to local extinction would benefit conservation planning. However, previous studies give little consensus on whether ranges decline to the core or edge. We built on previous work by using empirical data to examine the position of recent local extinctions within species' geographic ranges, address range position as a continuum, and explore the influence of environmental factors. We aggregated point-locality data for 125 Galliform species from across the Palearctic and Indo-Malaya into equal-area half-degree grid cells and used a multispecies dynamic Bayesian occupancy model to estimate rates of local extinctions. Our model provides a novel approach to identify loss of populations from within species ranges. We investigated the relationship between extinction rates and distance from range edge by examining whether patterns were consistent across biogeographic realm and different categories of land use. In the Palearctic, local extinctions occurred closer to the range edge than range core in both unconverted and human-dominated landscapes. In Indo-Malaya, no pattern was found for unconverted landscapes, but in human-dominated landscapes extinctions tended to occur closer to the core than the edge. Our results suggest that local and regional factors override general spatial patterns of recent local extinction within species' ranges and highlight the difficulty of predicting the parts of a species' distribution most vulnerable to threat. © 2017 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.
Quality Assessment of Physical and Organoleptic Instant Corn Rice on Scale-Up Process
NASA Astrophysics Data System (ADS)
Kumalasari, R.; Ekafitri, R.; Indrianti, N.
2017-12-01
Development of instant corn rice product has been successfully conducted on a laboratory scale. Corn has high carbohydrate content but low in fiber. The addition of fiber in instant corn rice, intended to improve the functioning of the product, and replace fiber loss during the process. Scale up process of Instant corn rice required to increase the production capacity. Scale up was the process to get identic output on a larger scale based on predetermined production scale. This study aimed to assess the changes and differences in the quality of instant corn rice during scale up. Instant corn rice scale up was done on production capacity 3 kg, 4 kg and 5 kg. Results showed that scale up of instant corn rice producing products with rehydration ratio ranges between 514% - 570%, the absorption rate ranged between 414% - 470%, swelling rate ranging between 119% - 134%, bulk density ranged from 0.3661 to 0.4745 (g/ml) and porosity ranging between 30-37%. The physical quality of instant corn rice on scale up were stable from the ones at laboratory scale on swelling rate, rehydration ratio, and absorption rate but not stable on bulk density and porosity. Organoleptic qualities were stable at increased scale compared on a laboratory scale. Bulk density was higher than those at laboratory scale, and the porosity was lower than those at laboratory scale.
NASA Astrophysics Data System (ADS)
Luo, Haibo; Teng, Jie; Chen, Shuang; Wang, Yu; Zhang, Hui
2017-10-01
Hot compression tests of 8009Al alloy reinforced with 15% SiC particles (8009Al/15%SiCp composites) prepared by powder metallurgy (direct hot extrusion methods) were performed on Gleeble-3500 system in the temperature range of 400-550 °C and strain rate range of 0.001-1 s-1. The processing map based on the dynamic material model was established to evaluate the flow instability regime and optimize processing parameters; the associated microstructural changes were studied by the observations of optical metallographic and scanning electron microscopy. The results showed that the flow stress increased initially and reached a plateau after peak stress value with increasing strain. The peak stress increased as the strain rate increased and deformation temperature decreased. The optimum parameters were identified to be deformation temperature range of 500-550 °C and strain rate range of 0.001-0.02 s-1 by combining the processing map with microstructural observation.
The ideal Kolmogorov inertial range and constant
NASA Technical Reports Server (NTRS)
Zhou, YE
1993-01-01
The energy transfer statistics measured in numerically simulated flows are found to be nearly self-similar for wavenumbers in the inertial range. Using the measured self-similar form, an 'ideal' energy transfer function and the corresponding energy flux rate were deduced. From this flux rate, the Kolmogorov constant was calculated to be 1.5, in excellent agreement with experiments.
Standardized Magnitude Estimations of Frequency and Amount for Use in Rating Extensivity.
ERIC Educational Resources Information Center
Bass, Bernard M.; And Others
Magnitude estimation was employed to find the numerical equivalents of 39 expressions of frequency ranging from never to always, and 44 expressions of amount ranging from none to all. The results were generalizable across three age-education-occupation levels and unaffected by whether ratings were an important or unimportant issue. Geometric means…
Orthogonal design on range hood with air curtain and its effects on kitchen environment.
Liu, Xiaomin; Wang, Xing; Xi, Guang
2014-01-01
Conventional range hoods cannot effectively prevent the oil fumes containing cooking-induced harmful material from escaping into the kitchen Air curtains and guide plates have been used in range hoods to reduce the escape of airborne emissions and heat, thereby improving the kitchen environment and the cook's degree of comfort. In this article, numerical simulations are used to study the effects of the jet velocity of an air curtain, the jet angle of the air curtain, the width of the jet slot, the area of the guide plate, and the exhaust rate of the range hood on the perceived temperature, the perceived concentration of oil fumes, the release temperature of oil fumes, and the concentration of escaped oil fumes in a kitchen. The orthogonal experiment results show that the exhaust rate of the range hood is the main factor influencing the fumes concentration and the temperature distribution in the kitchen. For the range hood examined in the present study, the optimum values of the exhaust rate, the jet velocity of the air curtain, the jet angle of the air curtain, the width of the jet slot, and the area of the guide plate are 10.5 m(3)/min, 1.5 m/s, -5°, 4 mm, and 0.22 m(2), respectively, based on the results of the parametric study. In addition, the velocity field, temperature field, and oil fumes concentration field in the kitchen using the proposed range hood with the air curtain and guide plate are analyzed for those parameters. The study's results provide significant information needed for improving the kitchen environment.
Detection-dependent kinetics as a probe of folding landscape microstructure.
Yang, Wei Yuan; Gruebele, Martin
2004-06-30
The folding landscapes of polypeptides and proteins exhibit a hierarchy of local minima. The causes range from proline isomerization all the way down to microstructure in the free energy caused by residual frustration inherent in even the best 20 amino acid design. The corresponding time scales range from hours to submicroseconds. The smallest microstructures are difficult to detect. We have measured the folding/unfolding kinetics of the engineered trpzip2 peptide at different tryptophan fluorescence wavelengths, each yielding a different rate. Wavelength-dependent folding kinetics on 0.1-2 mus time scales show that different microstructures with a range of solvent exposure and local dynamics are populated. We estimate a lower limit for the roughness of the free energy surface based on the range of rates observed.
Study of a close-grid geodynamic measurement system
NASA Technical Reports Server (NTRS)
1977-01-01
The Clogeos (Close-Grid Geodynamic Measurement System) concept, a complete range or range-rate measurement terminal installed in a satellite in a near-polar orbit with a network of relatively simple transponders or retro-reflectors on the ground at intervals of 0.1 to 10 km was reviewed. The distortion of the grid was measured in three dimensions to accuracies of + or - 1 cm with important applications to geodynamics, glaciology, and geodesy. User requirements are considered, and a typical grid, designed for earthquake prediction, was laid out along the San Andreas, Hayward, and Calaceras faults in southern California. The sensitivity of both range and range-rate measurements to small grid motions was determined by a simplified model. Variables in the model are satellite altitude and elevation angle plus grid displacements in latitude, and height.
Microfluidic flow rate detection based on integrated optical fiber cantilever.
Lien, Victor; Vollmer, Frank
2007-10-01
We demonstrate an integrated microfluidic flow sensor with ultra-wide dynamic range, suitable for high throughput applications such as flow cytometry and particle sorting/counting. A fiber-tip cantilever transduces flow rates to optical signal readout, and we demonstrate a dynamic range from 0 to 1500 microL min(-1) for operation in water. Fiber-optic sensor alignment is guided by preformed microfluidic channels, and the dynamic range can be adjusted in a one-step chemical etch. An overall non-linear response is attributed to the far-field angular distribution of single-mode fiber output.
NASA Technical Reports Server (NTRS)
Vangelder, B. H. W.
1978-01-01
Non-Bayesian statistics were used in simulation studies centered around laser range observations to LAGEOS. The capabilities of satellite laser ranging especially in connection with relative station positioning are evaluated. The satellite measurement system under investigation may fall short in precise determinations of the earth's orientation (precession and nutation) and earth's rotation as opposed to systems as very long baseline interferometry (VLBI) and lunar laser ranging (LLR). Relative station positioning, determination of (differential) polar motion, positioning of stations with respect to the earth's center of mass and determination of the earth's gravity field should be easily realized by satellite laser ranging (SLR). The last two features should be considered as best (or solely) determinable by SLR in contrast to VLBI and LLR.
NASA Astrophysics Data System (ADS)
Osada, Y.; Kido, M.; Ito, Y.; Iinuma, T.; Fujimoto, H.; Hino, R.
2014-12-01
Seafloor geodetic data, i.e. GPS/acoustic measurement and continuous seafloor pressure monitoring, brought important evidences showing that the 2011 Tohoku-oki earthquake (Mw 9.0) caused huge (> 50 m) coseismic slip near the Japan Trench. The postseismic behavior of the large slipped area is required to clarify to understand why large amount seismic slip could occur there. We started making direct-path acoustic ranging across the trench axis to reveal the convergence rate between the subducting Pacific and overriding continental plates. We expect the change of the baseline length across the trench axis, the plate boundary, reflects the slip rate at the shallow megathrust, which is difficult to estimate only from other geodetic observations largely affected by intraplate deformation caused by the postseismic viscoelastic relaxation process. To this end, we developed an ultra-deep seafloor acoustic ranging system. Our previous ranging systems have been designed to measure baseline length ~ 1 km and to be deployed up to 7,000 m water-depth (Osada et al., 2008, 2012). In order to realize the measurement across the Japan Trench, we improved this system to enhance range of acoustic ranging as well as operational depth of instruments. The improved system was designed to allow acoustic ranging up to 3 km and to be durable under the high-pressure equivalent to water depth of 9,000 m. In May 2013, we carried out a test deployment of the new ranging system. The system is composed of three seafloor instruments equipped with precision transponder (PXPs). Two of the PXPs were set on the landward slope of the Japan Trench, where large coseismic slip happened in 2011. Another PXP was deployed on the seaward side of the trench so that the baseline change associated with the slip on the plate boundary fault, if any, can be detected. Continuous records of baseline lengths were successfully obtained for four months. The repeatability of the distance measurements was about 20 mm for each of the two baselines. Although the duration of the observation was not long enough to estimate precise rate of baseline length changes, it is unlikely that the shortening rates of the baseline lengths exceed the rate of plate convergence (~ 8 cm/a). The results do not support occurrence of evident afterslip along the shallow plate boundary fault in 2013.
Shock Layer Radiation Modeling and Uncertainty for Mars Entry
NASA Technical Reports Server (NTRS)
Johnston, Christopher O.; Brandis, Aaron M.; Sutton, Kenneth
2012-01-01
A model for simulating nonequilibrium radiation from Mars entry shock layers is presented. A new chemical kinetic rate model is developed that provides good agreement with recent EAST and X2 shock tube radiation measurements. This model includes a CO dissociation rate that is a factor of 13 larger than the rate used widely in previous models. Uncertainties in the proposed rates are assessed along with uncertainties in translational-vibrational relaxation modeling parameters. The stagnation point radiative flux uncertainty due to these flowfield modeling parameter uncertainties is computed to vary from 50 to 200% for a range of free-stream conditions, with densities ranging from 5e-5 to 5e-4 kg/m3 and velocities ranging from of 6.3 to 7.7 km/s. These conditions cover the range of anticipated peak radiative heating conditions for proposed hypersonic inflatable aerodynamic decelerators (HIADs). Modeling parameters for the radiative spectrum are compiled along with a non-Boltzmann rate model for the dominant radiating molecules, CO, CN, and C2. A method for treating non-local absorption in the non-Boltzmann model is developed, which is shown to result in up to a 50% increase in the radiative flux through absorption by the CO 4th Positive band. The sensitivity of the radiative flux to the radiation modeling parameters is presented and the uncertainty for each parameter is assessed. The stagnation point radiative flux uncertainty due to these radiation modeling parameter uncertainties is computed to vary from 18 to 167% for the considered range of free-stream conditions. The total radiative flux uncertainty is computed as the root sum square of the flowfield and radiation parametric uncertainties, which results in total uncertainties ranging from 50 to 260%. The main contributors to these significant uncertainties are the CO dissociation rate and the CO heavy-particle excitation rates. Applying the baseline flowfield and radiation models developed in this work, the radiative heating for the Mars Pathfinder probe is predicted to be nearly 20 W/cm2. In contrast to previous studies, this value is shown to be significant relative to the convective heating.
O2 reduction and denitrification rates in shallow aquifers
NASA Astrophysics Data System (ADS)
Tesoriero, Anthony J.; Puckett, Larry J.
2011-12-01
O2 reduction and denitrification rates were determined in shallow aquifers of 12 study areas representing a wide range in sedimentary environments and climatic conditions. Zero- and first-order rates were determined by relating reactant or product concentrations to apparent groundwater age. O2 reduction rates varied widely within and between sites, with zero-order rates ranging from <3 μmol L-1 yr-1 to more than 140 μmol L-1 yr-1 and first-order rates ranging from 0.02 to 0.27 yr-1. Moderate denitrification rates (10-100 μmol N L-1 yr-1; 0.06-0.30 yr-1) were observed in most areas with O2 concentrations below 60 μmol L-1, while higher rates (>100 μmol N L-1 yr-1; >0.36 yr-1) occur when changes in lithology result in a sharp increase in the supply of electron donors. Denitrification lag times (i.e., groundwater travel times prior to the onset of denitrification) ranged from <20 yr to >80 yr. The availability of electron donors is indicated as the primary factor affecting O2 reduction rates. Concentrations of dissolved organic carbon (DOC) and/or sulfate (an indicator of sulfide oxidation) were positively correlated with groundwater age at sites with high O2 reduction rates and negatively correlated at sites with lower rates. Furthermore, electron donors from recharging DOC are not sufficient to account for appreciable O2 and nitrate reduction. These relations suggest that lithologic sources of DOC and sulfides are important sources of electrons at these sites but surface-derived sources of DOC are not. A review of published rates suggests that denitrification tends to occur more quickly when linked with sulfide oxidation than with carbon oxidation.
O 2 reduction and denitrification rates in shallow aquifers
Tesoriero, A.J.; Puckett, L.J.
2011-01-01
O 2 reduction and denitrification rates were determined in shallow aquifers of 12 study areas representing a wide range in sedimentary environments and climatic conditions. Zero-and first-order rates were determined by relating reactant or product concentrations to apparent groundwater age. O 2 reduction rates varied widely within and between sites, with zero-order rates ranging from <3 ??mol L -1 yr -1 to more than 140 ??mol L -1 yr -1 and first-order rates ranging from 0.02 to 0.27 yr -1. Moderate denitrification rates (10-100 ??mol N L -1 yr -1; 0.06-0.30 yr -1) were observed in most areas with O 2 concentrations below 60 mol L -1, while higher rates (>100 mol N L -1 yr -1; >0.36 yr -1) occur when changes in lithology result in a sharp increase in the supply of electron donors. Denitrification lag times (i.e., groundwater travel times prior to the onset of denitrification) ranged from <20 yr to >80 yr. The availability of electron donors is indicated as the primary factor affecting O 2 reduction rates. Concentrations of dissolved organic carbon (DOC) and/or sulfate (an indicator of sulfide oxidation) were positively correlated with groundwater age at sites with high O 2 reduction rates and negatively correlated at sites with lower rates. Furthermore, electron donors from recharging DOC are not sufficient to account for appreciable O 2 and nitrate reduction. These relations suggest that lithologic sources of DOC and sulfides are important sources of electrons at these sites but surface-derived sources of DOC are not. A review of published rates suggests that denitrification tends to occur more quickly when linked with sulfide oxidation than with carbon oxidation. copyright 2011 by the American Geophysical Union.
R. S. Criddle; B. N. Smith; L. D. Hansen; J. N. Church
2001-01-01
Many factors influence species range and diversity, but temperature and temperature variability are always major global determinants, irrespective of local constraints. On a global scale, the ranges of many taxa have been observed to increase and their diversity decrease with increasing latitude. On a local scale, gradients in species distribution are observable with...
Keane, Michael; Siert, Arlen; Stone, Samuel; Chen, Bean T.
2016-01-01
Nine gas metal arc welding (GMAW) processes for stainless steel were assessed for fume generation rates, fume generation rates per g of electrode consumed, and emission rates for hexavalent chromium (Cr6+). Elemental manganese, nickel, chromium, iron emissions per unit length of weld and labor plus consumables costs were similarly measured. Flux-cored arc welding and shielded metal arc (SMAW) processes were also studied. The objective was to identify the best welding processes for reducing workplace exposures, and estimate costs for all processes. Using a conical chamber, fumes were collected, weighed, recovered and analyzed by inductively-coupled atomic emission spectroscopy for metals, and by ion chromatography for Cr6+. GMAW processes used were Surface Tension Transfer™, Regulated Metal Deposition™, Cold Metal Transfer™, short-circuit, axial spray, and pulsed spray modes. Flux-cored welding used gas shielding; SMAW used E308 rods. Costs were estimated as dollars per m length of a ¼ in (6.3 mm) thick horizontal butt weld; equipment costs were estimated as ratios of new equipment costs to a 250 ampere capacity SMAW welding machine. Results indicate a broad range of fume emission factors for the processes studied. Fume emission rates per g of electrode were lowest for GMAW processes such as pulsed-spray mode (0.2 mg/g), and highest for SMAW (8 mg fume/g electrode). Emission rates of Cr6+ ranged from 50 to 7800 μg/min, and Cr6+ generation rates per g electrode ranged from 1 to 270μg/g. Elemental Cr generation rates spanned 13 to 330μg/g. Manganese emission rates ranged from 50 to 300μg/g. Nickel emission rates ranged from 4 to140 μg/g. Labor and consumables costs ranged from $3.15 (GMAW pulsed spray) to $7.40 (SMAW) per meter of finished weld, and were measured or estimated for all 11 processes tested. Equipment costs for some processes may be as much as 5 times the cost of a typical SMAW welding machine. The results show that all of the GMAW processes in this study can substantially reduce fume, Cr6+, manganese and costs relative to SMAW, the most commonly used welding process, and several have exceptional capabilities for reducing emissions. PMID:26267301
Keane, Michael; Siert, Arlen; Stone, Samuel; Chen, Bean T
2016-01-01
Nine gas metal arc welding (GMAW) processes for stainless steel were assessed for fume generation rates, fume generation rates per g of electrode consumed, and emission rates for hexavalent chromium (Cr(6+)). Elemental manganese, nickel, chromium, iron emissions per unit length of weld, and labor plus consumables costs were similarly measured. Flux-cored arc welding and shielded metal arc (SMAW) processes were also studied. The objective was to identify the best welding processes for reducing workplace exposures, and estimate costs for all processes. Using a conical chamber, fumes were collected, weighed, recovered, and analyzed by inductively coupled atomic emission spectroscopy for metals, and by ion chromatography for Cr(6+). GMAW processes used were Surface Tension Transfer, Regulated Metal Deposition, Cold Metal Transfer, short-circuit, axial spray, and pulsed spray modes. Flux-cored welding used gas shielding; SMAW used E308 rods. Costs were estimated as dollars per m length of a ¼ in (6.3 mm) thick horizontal butt weld; equipment costs were estimated as ratios of new equipment costs to a 250 ampere capacity SMAW welding machine. Results indicate a broad range of fume emission factors for the processes studied. Fume emission rates per g of electrode were lowest for GMAW processes such as pulsed-spray mode (0.2 mg/g), and highest for SMAW (8 mg fume/g electrode). Emission rates of Cr(6+) ranged from 50-7800 µg/min, and Cr(6+) generation rates per g electrode ranged from 1-270 µg/g. Elemental Cr generation rates spanned 13-330 µg/g. Manganese emission rates ranged from 50-300 µg/g. Nickel emission rates ranged from 4-140 µg/g. Labor and consumables costs ranged from $3.15 (GMAW pulsed spray) to $7.40 (SMAW) per meter of finished weld, and were measured or estimated for all 11 processes tested. Equipment costs for some processes may be as much as five times the cost of a typical SMAW welding machine. The results show that all of the GMAW processes in this study can substantially reduce fume, Cr(6+), manganese and costs relative to SMAW, the most commonly used welding process, and several have exceptional capabilities for reducing emissions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eisses, Amy
A high-resolution CHIRP seismic survey of Pyramid Lake, Nevada, located within the northern Walker Lane Deformation Belt, was conducted in summer 2010. Seismic CHIRP data with submeter vertical accuracy, together with piston and gravity cores, were used to calculate Holocene vertical slip rates, relative earthquake timing, and produce the first complete fault map beneath the lake. More than 500 line-kilometers of CHIRP data imaged complex fault patterns throughout the basin. Fault architecture beneath Pyramid Lake highlights a polarity flip, where down-to-the west patterns of sedimentation near the dextral Pyramid Lake fault to the south give way to down-to-the-east geometries tomore » the north within a mostly normal (i.e., Lake Range fault) and transtensional environment. The Lake Range fault predominantly controls extensional deformation within the northern two-thirds of the basin and exhibits varying degrees of asymmetric tilting and divergence due to along-strike segmentation. This observation is likely a combination of fault segments splaying onshore moving the focus of extension away from the lake coupled with some true along-strike differences in slip-rate. The combination of normal and oblique-slip faults in the northern basin gives Pyramid Lake its distinctive “fanning open to the north” tectonic geometry. The dense network of oblique-slip faults in the northwestern region of the lake, in contrast to the well-defined Lake Range fault, are short and discontinuous in nature, and possible represent a nascent shear zone. Preliminary vertical slip-rates measured across the Lake Range and other faults provide new estimates on the extension across the Pyramid Lake basin. A minimum vertical slip rate of ~1.0 mm/yr is estimated along the Lake Range fault, which yields a potential earthquake magnitude range between M6.4 and M7.0. A rapid influx of sediment was deposited shortly after the end of the Tioga glaciation somewhere between 12.5 ka to 9.5 ka and provides a punctuated short-term record of little to no slip on the Lake Range fault. In contrast, for the past 9,500 years, the basin has experienced a decrease in sedimentation rate, but an escalation in earthquake activity on the Lake Range fault, with the potential of 3 or 4 major earthquakes assuming a characteristic offset of 2.5 m per event. Regionally, our CHIRP investigation helps to reveal how strain is partitioned along the boundary between the eastern edge of the Walker Lane Deformation Belt and the northwest Great Basin proper.« less
Range Measurement as Practiced in the Deep Space Network
NASA Technical Reports Server (NTRS)
Berner, Jeff B.; Bryant, Scott H.; Kinman, Peter W.
2007-01-01
Range measurements are used to improve the trajectory models of spacecraft tracked by the Deep Space Network. The unique challenge of deep-space ranging is that the two-way delay is long, typically many minutes, and the signal-to-noise ratio is small. Accurate measurements are made under these circumstances by means of long correlations that incorporate Doppler rate-aiding. This processing is done with commercial digital signal processors, providing a flexibility in signal design that can accommodate both the traditional sequential ranging signal and pseudonoise range codes. Accurate range determination requires the calibration of the delay within the tracking station. Measurements with a standard deviation of 1 m have been made.
NASA Technical Reports Server (NTRS)
Flock, W. L.
1981-01-01
When high precision is required for range measurement on Earth space paths, it is necessary to correct as accurately as possible for excess range delays due to the dry air, water vapor, and liquid water content of the atmosphere. Calculations based on representative values of atmospheric parameters are useful for illustrating the order of magnitude of the expected delays. Range delay, time delay, and phase delay are simply and directly related. Doppler frequency variations or noise are proportional to the time rate of change of excess range delay. Tropospheric effects were examined as part of an overall consideration of the capability of precision two way ranging and Doppler systems.
Range-gated field disturbance sensor with range-sensitivity compensation
McEwan, T.E.
1996-05-28
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts in the sequence of bursts have a phase which varies. 8 figs.
Range-gated field disturbance sensor with range-sensitivity compensation
McEwan, Thomas E.
1996-01-01
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts in the sequence of bursts have a phase which varies.
A technology review of time-of-flight photon counting for advanced remote sensing
NASA Astrophysics Data System (ADS)
Lamb, Robert A.
2010-04-01
Time correlated single photon counting (TCSPC) has made tremendous progress during the past ten years enabling improved performance in precision time-of-flight (TOF) rangefinding and lidar. In this review the development and performance of several ranging systems is presented that use TCSPC for accurate ranging and range profiling over distances up to 17km. A range resolution of a few millimetres is routinely achieved over distances of several kilometres. These systems include single wavelength devices operating in the visible; multi-wavelength systems covering the visible and near infra-red; the use of electronic gating to reduce in-band solar background and, most recently, operation at high repetition rates without range aliasing- typically 10MHz over several kilometres. These systems operate at very low optical power (<100μW). The technique therefore has potential for eye-safe lidar monitoring of the environment and obvious military, security and surveillance sensing applications. The review will highlight the theoretical principles of photon counting and progress made in developing absolute ranging techniques that enable high repetition rate data acquisition that avoids range aliasing. Technology trends in TCSPC rangefinding are merging with those of quantum cryptography and its future application to revolutionary quantum imaging provides diverse and exciting research into secure covert sensing, ultra-low power active imaging and quantum rangefinding.
NASA Astrophysics Data System (ADS)
Qiu, Jie; Cheng, Zhi-Wen; Zhu, Xi-Ming; Pu, Yi-Kang
2018-04-01
The rate coefficients for the electron-impact transfer from Kr(1s5) to Kr(1s4) and from Kr(1s3) to Kr(1s2) are measured in the electron temperature (T e) range between 0.07 eV and 1 eV. In the afterglow of a capacitive krypton discharge at a fixed pressure of 20 mTorr and a peak rf power ranging from 4 to 128 W, the densities of four krypton 1s states, the electron temperature and the electron density are measured by diode laser absorption, a Langmuir probe and a microwave interferometer, respectively. With these measured quantities, the rate coefficients are obtained from a population model for krypton metastable states. The measured rate coefficients are compared with those derived from the excitation cross sections of Kr metastable states calculated by different R-matrix models. It is found that our results agree best with that from Allan et al [1]. Moreover, we analyze the assumptions made in the population model and discuss their possible impact on the accuracy of the measured rate coefficients, especially for the low T e (0.1-0.2 eV) range and a higher T e (0.4-1 eV) range.
Rice-Townsend, Samuel; Barnes, Jeff N; Hall, Matthew; Baxter, Jessica L; Rangel, Shawn J
2014-06-01
To characterize the scope and magnitude of practice variation associated with the diagnosis and treatment of appendicitis at freestanding children's hospitals. Variation in care has been associated with poor outcomes and is believed to be a key driver of excess health care spending. Retrospective cohort study of 13,328 patients treated with appendicitis at 34 children's hospitals (9/2010-9/2011). Patients were divided into complicated and uncomplicated cohorts and examined for interhospital variation in the use of diagnostic imaging (computed tomography or ultrasonography), laboratory tests, parenteral nutrition (PN), peripherally inserted central catheters (PICC), and hospital cost. The number and distribution of statistical outliers were calculated for all measures. Significant variation was found for all measures, including a 3.5-fold difference in preoperative imaging (aggregate rate: 49.0%, range across hospitals: 21.2%-73.5%, P < 0.001) and a 5-fold difference in preoperative laboratory utilization (aggregate median: 2 tests/encounter, range: 1-5 tests/encounter, P < 0.001). For patients with complicated appendicitis, we characterized a 12-fold difference in postoperative imaging (aggregate rate: 19.4%, range: 4.9%-61.6%, P < 0.001), a 48-fold difference in PICC lines (aggregate rate: 18.9%, range: 1.7%-81.8%, P < 0.001), and a 100-fold difference in PN utilization (aggregate rate: 9.3%, range: 0.4%-42.0%, P < 0.001). Median hospital cost differed 4-fold for patients with uncomplicated disease (aggregate median: $6804, range: $4200-$16,796, P < 0.001) and 4.6-fold for patients with complicated disease (aggregate median: $13,138, range: $5419-$24,779, P < 0.001). Statistical outliers on the basis of high and low utilization were identified for all measures. Significant variation exists in practice, resource utilization, and treatment-related cost associated with the management of appendicitis at freestanding children's hospitals. Value-based measures are needed for benchmarking and to prioritize collaborative quality improvement efforts.
Glacial reorganization of topography in a tectonically active mountain range
NASA Astrophysics Data System (ADS)
Adams, Byron; Ehlers, Todd
2016-04-01
Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns, and not tectonic rock uplift rates. Alpine glaciers drastically altered the relief structure of the Olympic Mountains. The details of these relief changes are recorded in channel profiles as overdeepenings, reduced slopes, and associated knickpoints. We find the position of these relief changes within the orogen is dependent on the position of the Pleistocene ELA. While alpine glaciers overdeepened valleys in regions near the Pleistocene ELA (which has a tendency to increase relief), headward erosion of west and north flowing glacier systems captured significant area from opposing systems and caused drainage divide lowering. This divide lowering reduced relief throughout the range. We demonstrate similar topographic effects recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on topography makes the argument of mountain range steadiness untenable in significantly glaciated settings. Furthermore, our results suggest that most glaciated Cenozoic ranges are likely still in a mode of readjustment as fluvial systems change topography and erosion rates to equilibrate with rock uplift rates.
Analysis of One-Way Laser Ranging Data to LRO, Time Transfer and Clock Characterization
NASA Technical Reports Server (NTRS)
Bauer, S.; Hussmann, H.; Oberst, J.; Dirkx, D.; Mao, D.; Neumann, G. A.; Mazarico, E.; Torrence, M. H.; McGarry, J. F.; Smith, D. E.;
2016-01-01
We processed and analyzed one-way laser ranging data from International Laser Ranging Service ground stations to NASA's Lunar Reconnaissance Orbiter (LRO), obtained from June 13, 2009 until September 30, 2014. We pair and analyze the one-way range observables from station laser fire and spacecraft laser arrival times by using nominal LRO orbit models based on the GRAIL gravity field. We apply corrections for instrument range walk, as well as for atmospheric and relativistic effects. In total we derived a tracking data volume of approximately 3000 hours featuring 64 million Full Rate and 1.5 million Normal Point observations. From a statistical analysis of the dataset we evaluate the experiment and the ground station performance. We observe a laser ranging measurement precision of 12.3 centimeters in case of the Full Rate data which surpasses the LOLA (Lunar Orbiting Laser Altimeter) timestamp precision of 15 centimeters. The averaging to Normal Point data further reduces the measurement precision to 5.6 centimeters. We characterized the LRO clock with fits throughout the mission time and estimated the rate to 6.9 times10 (sup -8), the aging to 1.6 times 10 (sup -12) per day and the change of aging to 2.3 times 10 (sup -14) per day squared over all mission phases. The fits also provide referencing of onboard time to the TDB (Barycentric Dynamical Time) time scale at a precision of 166 nanoseconds over two and 256 nanoseconds over all mission phases, representing ground to space time transfer. Furthermore we measure ground station clock differences from the fits as well as from simultaneous passes which we use for ground to ground time transfer from common view observations. We observed relative offsets ranging from 33 to 560 nanoseconds and relative rates ranging from 2 times 10 (sup -13) to 6 times 10 (sup -12) between the ground station clocks during selected mission phases. We study the results from the different methods and discuss their applicability for time transfer.
SPIN EVOLUTION OF ACCRETING YOUNG STARS. II. EFFECT OF ACCRETION-POWERED STELLAR WINDS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matt, Sean P.; Pinzon, Giovanni; Greene, Thomas P.
2012-01-20
We present a model for the rotational evolution of a young, solar-mass star interacting magnetically with an accretion disk. As in a previous paper (Paper I), the model includes changes in the star's mass and radius as it descends the Hayashi track, a decreasing accretion rate, and a prescription for the angular momentum transfer between the star and disk. Paper I concluded that, for the relatively strong magnetic coupling expected in real systems, additional processes are necessary to explain the existence of slowly rotating pre-main-sequence stars. In the present paper, we extend the stellar spin model to include the effectmore » of a spin-down torque that arises from an accretion-powered stellar wind (APSW). For a range of magnetic field strengths, accretion rates, initial spin rates, and mass outflow rates, the modeled stars exhibit rotation periods within the range of 1-10 days in the age range of 1-3 Myr. This range coincides with the bulk of the observed rotation periods, with the slow rotators corresponding to stars with the lowest accretion rates, strongest magnetic fields, and/or highest stellar wind mass outflow rates. We also make a direct, quantitative comparison between the APSW scenario and the two types of disk-locking models (namely, the X-wind and Ghosh and Lamb type models) and identify some remaining theoretical issues for understanding young star spins.« less
Spin Evolution of Accreting Young Stars. II. Effect of Accretion-powered Stellar Winds
NASA Astrophysics Data System (ADS)
Matt, Sean P.; Pinzón, Giovanni; Greene, Thomas P.; Pudritz, Ralph E.
2012-01-01
We present a model for the rotational evolution of a young, solar-mass star interacting magnetically with an accretion disk. As in a previous paper (Paper I), the model includes changes in the star's mass and radius as it descends the Hayashi track, a decreasing accretion rate, and a prescription for the angular momentum transfer between the star and disk. Paper I concluded that, for the relatively strong magnetic coupling expected in real systems, additional processes are necessary to explain the existence of slowly rotating pre-main-sequence stars. In the present paper, we extend the stellar spin model to include the effect of a spin-down torque that arises from an accretion-powered stellar wind (APSW). For a range of magnetic field strengths, accretion rates, initial spin rates, and mass outflow rates, the modeled stars exhibit rotation periods within the range of 1-10 days in the age range of 1-3 Myr. This range coincides with the bulk of the observed rotation periods, with the slow rotators corresponding to stars with the lowest accretion rates, strongest magnetic fields, and/or highest stellar wind mass outflow rates. We also make a direct, quantitative comparison between the APSW scenario and the two types of disk-locking models (namely, the X-wind and Ghosh & Lamb type models) and identify some remaining theoretical issues for understanding young star spins.
Prych, Edmund A.
1995-01-01
Long-term average deep-percolation rates of water from precipitation on the U.S. Department of Energy Hanford Site in semiarid south-central Washington, as estimated by a chloride mass-balance method, range from 0.008 to 0.30 mm/yr (millimeters per year) at nine locations covered by a variety of fine-grain soils and vegetated with sagebrush and other deep-rooted plants plus sparse shallow-rooted grasses. Deep-percolation rates estimated using a chlorine-36 bomb-pulse method at three of the nine locations range from 2.1 to 3.4 mm/yr. Because the mass-balance method may underestimate percolation rates and the bomb-pulse method probably overestimates percolation rates, estimates by the two methods probably bracket actual rates. These estimates, as well as estimates by previous investigators who used different methods, are a small fraction of mean annual precipitation, which ranges from about 160 to 210 mm/yr at the different test locations. Estimates by the mass-balance method at four locations in an area that is vegetated only with sparse shallow-rooted grasses range from 0.39 to 2.0 mm/yr. Chlorine-36 data at one location in this area were sufficient only to determine that the upper limit of deep percolation is more than 5.1 mm/yr. Although estimates for locations in this area are larger than the estimates for locations with deep-rooted plants, they are at the lower end of the range of estimates for this area made by previous investigators.
Anxiety, depression, and PTSD following cardiac arrest: a systematic review of the literature.
Wilder Schaaf, Kathryn P; Artman, Laura K; Peberdy, Mary Ann; Walker, William C; Ornato, Joseph P; Gossip, Michelle R; Kreutzer, Jeffrey S
2013-07-01
Identify the occurrence rate of post-arrest psychological distress; evaluate methodological approaches; suggest future research priorities; address clinical implications. The electronic databases PubMed/MEDLINE and PsychInfo/APA PsycNET were utilized to search for terms including 'Cardiac Arrest', 'Therapeutic Hypothermia' and 'Depression', 'Anxiety', 'Quality of Life', 'Posttraumatic Stress Disorder (PTSD)', 'Psychological Outcomes', 'Hospital Anxiety and Depression Scale (HADS)', and 'Beck Depression Inventory (BDI)'. High rates of psychological distress have been reported after OHCA. Specifically, incidence rates of depression have ranged from 14% to 45%; anxiety rates have ranged from 13% to 61%; PTSD rates reportedly range from 19% to 27%. Variability between studies is likely attributable to methodological variations relating to measures used, time since arrest, and research setting. Given the occurrence rate of psychological distress after OHCA, psychological screening and early intervention seems indicated in the cardiac arrest population. Further studies are needed to better establish occurrence rates in both inpatient and outpatient settings, determine appropriate measures and normative cut off scores, and decide on the most appropriate method of intervention. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Output rate of magma from active central volcanoes
NASA Technical Reports Server (NTRS)
Wadge, G.
1980-01-01
For part of their historic records, nine of the most active volcanoes on earth have each erupted magma at a nearly constant rate. These output rates are very similar and range from 0.69 to 0.26 cu m/s. The volcanoes discussed - Kilauea, Mauna Loa, Fuego, Santiaguito, Nyamuragira, Hekla, Piton de la Fournaise, Vesuvius and Etna - represent almost the whole spectrum of plate tectonic settings of volcanism. A common mechanism of buoyantly rising magma-filled cracks in the upper crust may contribute to the observed restricted range of the rates of output.
Growth and erosion of mountain ranges at the northeastern margin of Tibet
NASA Astrophysics Data System (ADS)
Hetzel, Ralf; Palumbo, Luigi; Giese, Jörg; Guo, Jianming
2010-05-01
The hypothesis that mountain belts may reach a steady state, in which rock uplift is balanced by erosion, has been supported by numerous field studies and numerical models. The early evolution of mountain ranges, however, and especially the relation between fault growth and topographic response has received little attention. By using a space-for-time substitution we illustrate how active thrust faults and small, fault-bounded mountain ranges evolve into mature mountain chains that will ultimately be incorporated into the laterally growing Tibetan Plateau. At an early stage of development, when faults propagate laterally, slip rates are constant along strike [1-3]. As long as no significant topographic relief has developed, tectonic uplift is at least an order of magnitude faster than the rate of erosion [2,4]. During progressive relief growth and the establishment of drainage basins, erosion of the rising mountain ranges becomes more important, but the studied ranges are still in a pre-steady state and continue to grow both vertically and laterally [5]. During this stage the rate of erosion is linearly correlated to the mean hillslope gradient and the mean local relief, if differences in lithology or rock strength are negligible [6]. The rate of relief growth may be inferred from the difference between local erosion rates on ridge crests and catchment-wide denudation rates [7] - the latter may be taken as a surrogate for the rate of river incision. As hillslopes approach a threshold value, landsliding becomes the dominant process of mass transport and erosion rates increase non-linearly with slope. Once a steady state has been reached, the erosion rate is equal to the rate of rock uplift. A key problem is how the rate of rock uplift can be quantified in such regions, because the stochastic distribution of landslides causes the denudation rates inferred from 10Be in river sediment to be highly variable [8]. References [1] Hetzel et al. (2004). Implications of the fault scaling law for the growth of topography: Mountain ranges in the broken foreland of NE Tibet. Terra Nova 16, 157-162. [2] Hetzel et al. (2002). Low slip rates and long-term preservation of geomorphic features in Central Asia. Nature 417, 428-432. [3] Hetzel et al. (2004). Late Pleistocene/Holocene slip rate of the Zhangye thrust (Qilian Shan, China) and implications for the active growth of the northeastern Tibetan Plateau, Tectonics 23, TC6006, doi:10.1029/2004TC001653. [4] Goethals et al. (2009). Determining the impact of faulting on the rate of erosion in a low-relief landscape: A case study using in situ produced 21Ne on active normal faults in the Bishop Tuff, California. Geomorphology 103, 401-413. [5] Palumbo et al. (2009). Deciphering the rate of mountain growth during topographic presteady state: an example from the NE margin of the Tibetan Plateau. Tectonics 28, TC4017, doi:10.1029/2009TC002455. [6] Palumbo et al. (in press). Topographic and lithologic control on catchment-wide denudation rates derived from cosmogenic 10Be in two mountain ranges at the margin of NE Tibet. Geomorphology, doi:10.1016/j.geomorph.2009.11.019. [7] Meyer et al. (in press). Determining the growth rate of topographic relief using in situ-produced 10Be: A case study in the Black Forest, Germany. Earth and Planetary Science Letters. [8] Densmore et al. (2009). Spatial variations in catchment-averaged denudation rates from normal fault footwalls. Geology 37, 1139-1142.
Anti-aliasing techniques in photon-counting depth imaging using GHz clock rates
NASA Astrophysics Data System (ADS)
Krichel, Nils J.; McCarthy, Aongus; Collins, Robert J.; Buller, Gerald S.
2010-04-01
Single-photon detection technologies in conjunction with low laser illumination powers allow for the eye-safe acquisition of time-of-flight range information on non-cooperative target surfaces. We previously presented a photon-counting depth imaging system designed for the rapid acquisition of three-dimensional target models by steering a single scanning pixel across the field angle of interest. To minimise the per-pixel dwelling times required to obtain sufficient photon statistics for accurate distance resolution, periodic illumination at multi- MHz repetition rates was applied. Modern time-correlated single-photon counting (TCSPC) hardware allowed for depth measurements with sub-mm precision. Resolving the absolute target range with a fast periodic signal is only possible at sufficiently short distances: if the round-trip time towards an object is extended beyond the timespan between two trigger pulses, the return signal cannot be assigned to an unambiguous range value. Whereas constructing a precise depth image based on relative results may still be possible, problems emerge for large or unknown pixel-by-pixel separations or in applications with a wide range of possible scene distances. We introduce a technique to avoid range ambiguity effects in time-of-flight depth imaging systems at high average pulse rates. A long pseudo-random bitstream is used to trigger the illuminating laser. A cyclic, fast-Fourier supported analysis algorithm is used to search for the pattern within return photon events. We demonstrate this approach at base clock rates of up to 2 GHz with varying pattern lengths, allowing for unambiguous distances of several kilometers. Scans at long stand-off distances and of scenes with large pixel-to-pixel range differences are presented. Numerical simulations are performed to investigate the relative merits of the technique.
Motor Controller System For Large Dynamic Range of Motor Operation
NASA Technical Reports Server (NTRS)
Howard, David E. (Inventor); Alhorn, Dean C. (Inventor); Smith, Dennis A. (Inventor); Dutton, Kenneth R. (Inventor); Paulson, Mitchell Scott (Inventor)
2006-01-01
A motor controller system uses a rotary sensor with a plurality of signal conditioning units, coupled to the rotary sensor. Each of these units, which is associated with a particular range of motor output shaft rotation rates, generate a feedback signal indicative of the position of the motor s output shaft. A controller (i) converts a selected motor output shaft rotation rate to a corresponding incremental amount of rotational movement for a selected fixed time period, (ii) selects, at periodic completions of the selected fixed time period, the feedback signal from one of the signal conditioning units for which the particular range of motor output shaft rotation rates associated therewith encompasses the selected motor output shaft rotation rate, and (iii) generates a motor drive signal based on a difference between the incremental amount of rotational movement and the feedback signal from the selected one of the signal conditioning Units.
The biodiversity of species and their rates of extinction, distribution, and protection.
Pimm, S L; Jenkins, C N; Abell, R; Brooks, T M; Gittleman, J L; Joppa, L N; Raven, P H; Roberts, C M; Sexton, J O
2014-05-30
Recent studies clarify where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. We assess key statistics about species, their distribution, and their status. Most are undescribed. Those we know best have large geographical ranges and are often common within them. Most known species have small ranges. The numbers of small-ranged species are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. Current rates of extinction are about 1000 times the likely background rate of extinction. Future rates depend on many factors and are poised to increase. Although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity. Copyright © 2014, American Association for the Advancement of Science.
ERIC Educational Resources Information Center
Nadig, Aparna; Shaw, Holly
2012-01-01
Are there consistent markers of atypical prosody in speakers with high functioning autism (HFA) compared to typically-developing speakers? We examined: (1) acoustic measurements of pitch range, mean pitch and speech rate in conversation, (2) perceptual ratings of conversation for these features and overall prosody, and (3) acoustic measurements of…
Mortality of aspen on the Gros Ventre elk winter range
Richard G. Krebill
1972-01-01
Stands of aspen on the Gros Ventre elk winter range of northwestern Wyoming are suffering high mortality and are not regenerating satisfactorily. If the 1970 mortality rate (3.6 percent) continues, about a two-thirds reduction in the numbers of tree-sized aspen can be expected by year 2000. Collected evidence suggests that the mortality rate is unusually high because...
Fiona L. Jordan; J. Jason L. Cantera; Mark E. Fenn; Lisa Y. Stein
2005-01-01
Deposition rates of atmospheric nitrogenous pollutants to forests in the San Bernardino Mountains range east of Los Angeles, California, are the highest reported in North America. Acidic soils from the west end of the range are N-saturated and have elevated rates of N-mineralization, nitrification, and nitrate leaching. We assessed the impact of this heavy nitrogen...
Volatility spillover between crude oil and exchange rate: A copula-CARR approach
NASA Astrophysics Data System (ADS)
Pu, Y. J.; Guo, M. Y.
2017-11-01
Oil provides a powerful impetus for modern society's production and life. The influences of oil price fluctuations on socio-economic development are obvious, and it draws more attention from scholars. However, the distribution of oil is highly centralized, which leads to the vast majority of oil trading through foreign trade. As a result, exchange rate plays an important role in the oil business. Study on the relationship between exchange rate and crude oil gradually becomes a hot research topic in recent years. In this paper, we use copula and CARR model to study correlation structure and relationship between crude oil price and exchange rate. We establish CARR models as marginal models and use five copulas which are Gaussian Copula, Student-t Copula, Gumbel Copula, Clayton Copula and Frank Copula to study the correlation structure between NYMEX crude oil price range and U. S. Dollar Index range. Furthermore, we use Copula-CARR model with structural breaks to detect the change points in the correlation structure between NYMEX crude oil price range and U. S. Dollar Index range. Empirical results show that the change points are closely related to the actual economic events.
NASA Technical Reports Server (NTRS)
Chapman, A. J.
1973-01-01
Reusable surface insulation materials, which were developed as heat shields for the space shuttle, were tested over a range of conditions including heat-transfer rates between 160 and 620 kW/sq m. The lowest of these heating rates was in a range predicted for the space shuttle during reentry, and the highest was more than twice the predicted entry heating on shuttle areas where reusable surface insulation would be used. Individual specimens were tested repeatedly at increasingly severe conditions to determine the maximum heating rate and temperature capability. A silica-base material experienced only minimal degradation during repeated tests which included conditions twice as severe as predicted shuttle entry and withstood cumulative exposures three times longer than the best mullite material. Mullite-base materials cracked and experienced incipient melting at conditions within the range predicted for shuttle entry. Neither silica nor mullite materials consistently survived the test series with unbroken waterproof surfaces. Surface temperatures for a silica and a mullite material followed a trend expected for noncatalytic surfaces, whereas surface temperatures for a second mullite material appeared to follow a trend expected for a catalytic surface.
NASA Astrophysics Data System (ADS)
Ding, Zong-ye; Hu, Qiao-dan; Zeng, Long; Li, Jian-guo
2016-11-01
Isothermal hot compression tests of as-cast high-Cr ultra-super-critical (USC) rotor steel with columnar grains perpendicular to the compression direction were carried out in the temperature range from 950 to 1250°C at strain rates ranging from 0.001 to 1 s-1. The softening mechanism was dynamic recovery (DRV) at 950°C and the strain rate of 1 s-1, whereas it was dynamic recrystallization (DRX) under the other conditions. A modified constitutive equation based on the Arrhenius model with strain compensation reasonably predicted the flow stress under various deformation conditions, and the activation energy was calculated to be 643.92 kJ•mol-1. The critical stresses of dynamic recrystallization under different conditions were determined from the work-hardening rate ( θ)-flow stress ( σ) and -∂ θ/∂ σ-σ curves. The optimum processing parameters via analysis of the processing map and the softening mechanism were determined to be a deformation temperature range from 1100 to 1200°C and a strain-rate range from 0.001 to 0.08 s-1, with a power dissipation efficiency η greater than 31%.
Ultrafast optical ranging using microresonator soliton frequency combs
NASA Astrophysics Data System (ADS)
Trocha, P.; Karpov, M.; Ganin, D.; Pfeiffer, M. H. P.; Kordts, A.; Wolf, S.; Krockenberger, J.; Marin-Palomo, P.; Weimann, C.; Randel, S.; Freude, W.; Kippenberg, T. J.; Koos, C.
2018-02-01
Light detection and ranging is widely used in science and industry. Over the past decade, optical frequency combs were shown to offer advantages in optical ranging, enabling fast distance acquisition with high accuracy. Driven by emerging high-volume applications such as industrial sensing, drone navigation, or autonomous driving, there is now a growing demand for compact ranging systems. Here, we show that soliton Kerr comb generation in integrated silicon nitride microresonators provides a route to high-performance chip-scale ranging systems. We demonstrate dual-comb distance measurements with Allan deviations down to 12 nanometers at averaging times of 13 microseconds along with ultrafast ranging at acquisition rates of 100 megahertz, allowing for in-flight sampling of gun projectiles moving at 150 meters per second. Combining integrated soliton-comb ranging systems with chip-scale nanophotonic phased arrays could enable compact ultrafast ranging systems for emerging mass applications.
The Rate of Beneficial Mutations Surfing on the Wave of a Range Expansion
Lehe, Rémi; Hallatschek, Oskar; Peliti, Luca
2012-01-01
Many theoretical and experimental studies suggest that range expansions can have severe consequences for the gene pool of the expanding population. Due to strongly enhanced genetic drift at the advancing frontier, neutral and weakly deleterious mutations can reach large frequencies in the newly colonized regions, as if they were surfing the front of the range expansion. These findings raise the question of how frequently beneficial mutations successfully surf at shifting range margins, thereby promoting adaptation towards a range-expansion phenotype. Here, we use individual-based simulations to study the surfing statistics of recurrent beneficial mutations on wave-like range expansions in linear habitats. We show that the rate of surfing depends on two strongly antagonistic factors, the probability of surfing given the spatial location of a novel mutation and the rate of occurrence of mutations at that location. The surfing probability strongly increases towards the tip of the wave. Novel mutations are unlikely to surf unless they enjoy a spatial head start compared to the bulk of the population. The needed head start is shown to be proportional to the inverse fitness of the mutant type, and only weakly dependent on the carrying capacity. The precise location dependence of surfing probabilities is derived from the non-extinction probability of a branching process within a moving field of growth rates. The second factor is the mutation occurrence which strongly decreases towards the tip of the wave. Thus, most successful mutations arise at an intermediate position in the front of the wave. We present an analytic theory for the tradeoff between these factors that allows to predict how frequently substitutions by beneficial mutations occur at invasion fronts. We find that small amounts of genetic drift increase the fixation rate of beneficial mutations at the advancing front, and thus could be important for adaptation during species invasions. PMID:22479175
NASA Astrophysics Data System (ADS)
Graur, Or; SDF SN Team
2012-01-01
The Type Ia supernova (SN Ia) rate, when compared to the cosmic star formation history (SFH), can be used to derive the delay-time distribution (DTD; the hypothetical SN Ia rate versus time following a brief burst of star formation) of SNe Ia, which can distinguish among progenitor models. We present the results of a supernova (SN) survey in the Subaru Deep Field (SDF). Over a period of 3 years, we have observed the SDF on four independent epochs with Suprime-Cam on the Subaru 8.2-m telescope, with two nights of exposure per epoch, in the R, i'and z‧ bands. We have discovered 150 SNe out to redshift z≈ 2. Our final sample includes 28 SNe Ia in the range 1.0 < z < 1.5 and 10 in the range 1.5 < z < 2.0. As our survey is largely insensitive to core-collapse SNe (CC SNe) at z > 1, most of the events found in this range are likely SNe Ia. Based on this sample, we find that the SN Ia rate evolution levels off at 1.0 < z < 2.0, but shows no sign of declining. Combining our SN Ia rate measurements and those from the literature, and comparing to a wide range of possible SFHs, the best-fitting DTD (with a reduced χ2= 0.7) is a power law of the form &Psi(t) ∝tβ, with index β=-1.1 ± 0.1 (statistical) ±0.17 (systematic). By combining the contribution from CC SNe, based on the wide range of SFHs, with that from SNe Ia, calculated with the best-fitting DTD, we predict that the mean present-day cosmic iron abundance is in the range ZFe= (0.09-0.37) ZFe, ⊙.
NASA Astrophysics Data System (ADS)
Burgarella, Denis; Ciesla, Laure; Boquien, Mederic; Buat, Veronique; Roehlly, Yannick
2015-09-01
The star formation rate density traces the formation of stars in the universe. To estimate the star formation rate of galaxies, we can use a wide range of star formation tracers: continuum measurements in most wavelength domains, lines, supernovae and GRBs... All of them have pros and cons. Most of the monochromatic tracers are hampered but the effects of dust. But, before being able to estimate the star formation rate, we first need to obtain a safe estimate to the dust attenuation. The advantage of the X-ray wavelength range is that we can consider it as free from the effect of dust. In this talk, we will estimate how many galaxies we could detect with ATHENA to obtain the star formation density. For this, I will use my recent Herschel paper where the total (UV + IR) star formation rate density was evaluated up to z ~ 4 and provide quantitative figures for what ATHENA will detect as a function of the redshift and the luminosity. ATHENA will need predictions that are in agreement with what we observe in the other wavelength ranges. I will present the code CIGALE (http://cigale.lam.fr). The new and public version of CIGALE (released in April 2015) allows to model the emission of galaxies from the far-ultraviolet to the radio and it can make prediction in any of these wavelength ranges. I will show how galaxy star formation rates can be estimated in a way that combines all the advantages of monochromatic tracers but not the caveats. It should be stressed that we can model the emission of AGNs in the FUV-to-FIR range using several models. Finally, I will explain why we seriously consider to extend CIGALE to the x-ray range to predict the X-ray emission of galaxies including any AGN.
Stoller, Oliver; Schindelholz, Matthias; Bichsel, Lukas; Schuster, Corina; de Bie, Rob A; de Bruin, Eling D; Hunt, Kenneth J
2014-07-01
The majority of post-stroke individuals suffer from low exercise capacity as a secondary reaction to immobility. The aim of this study was to prove the concept of feedback-controlled robotics-assisted treadmill exercise (RATE) to assess aerobic capacity and guide cardiovascular exercise in severely impaired individuals early after stroke. Subjects underwent constant load and incremental exercise testing using a human-in-the-loop feedback system within a robotics-assisted exoskeleton (Lokomat, Hocoma AG, CH). Inclusion criteria were: stroke onset ≤8 weeks, stable medical condition, non-ambulatory status, moderate motor control of the lower limbs and appropriate cognitive function. Outcome measures included oxygen uptake kinetics, peak oxygen uptake (VO2peak), gas exchange threshold (GET), peak heart rate (HRpeak), peak work rate (Ppeak) and accuracy of reaching target work rate (P-RMSE). Three subjects (18-42 d post-stroke) were included. Oxygen uptake kinetics during constant load ranged from 42.0 to 60.2 s. Incremental exercise testing showed: VO2peak range 19.7-28.8 ml/min/kg, GET range 11.6-12.7 ml/min/kg, and HRpeak range 115-161 bpm. Ppeak range was 55.2-110.9 W and P-RMSE range was 3.8-7.5 W. The concept of feedback-controlled RATE for assessment of aerobic capacity and guidance of cardiovascular exercise is feasible. Further research is warranted to validate the method on a larger scale. Aerobic capacity is seriously reduced in post-stroke individuals as a secondary reaction to immobility. Robotics-assisted walking devices may have substantial clinical relevance regarding assessment and improvement of aerobic capacity early after stroke. Feedback-controlled robotics-assisted treadmill exercise represents a new concept for cardiovascular assessment and intervention protocols for severely impaired individuals.
Krishnan, Ananthanarayan; Gandour, Jackson T.; Suresh, Chandan H.
2015-01-01
The aim of this study is to determine how pitch acceleration rates within and outside the normal pitch range may influence latency and amplitude of cortical pitch-specific responses (CPR) as a function of language experience (Chinese, English). Responses were elicited from a set of four pitch stimuli chosen to represent a range of acceleration rates (two each inside and outside the normal voice range) imposed on the high rising Mandarin Tone 2. Pitch-relevant neural activity, as reflected in the latency and amplitude of scalp-recorded CPR components, varied depending on language-experience and pitch acceleration of dynamic, time-varying pitch contours. Peak latencies of CPR components were shorter in the Chinese than the English group across stimuli. Chinese participants showed greater amplitude than English for CPR components at both frontocentral and temporal electrode sites in response to pitch contours with acceleration rates inside the normal voice pitch range as compared to pitch contours with acceleration rates that exceed the normal range. As indexed by CPR amplitude at the temporal sites, a rightward asymmetry was observed for the Chinese group only. Only over the right temporal site was amplitude greater in the Chinese group relative to the English. These findings may suggest that the neural mechanism(s) underlying processing of pitch in the right auditory cortex reflect experience-dependent modulation of sensitivity to acceleration in just those rising pitch contours that fall within the bounds of one’s native language. More broadly, enhancement of native pitch stimuli and stronger rightward asymmetry of CPR components in the Chinese group is consistent with the notion that long-term experience shapes adaptive, distributed hierarchical pitch processing in the auditory cortex, and reflects an interaction with higher-order, extrasensory processes beyond the sensory memory trace. PMID:26166727
NASA Astrophysics Data System (ADS)
Li, G.; Campbell, D. A.
2015-10-01
Among marine phytoplankton groups, diatoms span the widest range of cell size, with resulting effects upon their nitrogen uptake, photosynthesis and growth responses to light. We grew two strains of marine centric diatoms, the small Thalassiosira pseudonana and the larger T. punctigera in high and low nitrogen media, across a range of growth light levels. Nitrogen and total proteins per cell decreased with increasing growth light in both species when grown under low nitrogen media. Surprisingly, low nitrogen increased the cellular allocation to RUBISCO and the rate of electron transport away from Photosystem II for the smaller diatom under low growth light, and for the larger diatom across the range of growth lights. Low nitrogen decreased the growth rate of the smaller diatom, particularly under higher light, but stimulated the growth rate of the larger diatom. Our results show that the high nitrogen in common growth media favours the growth rate of a small diatom but inhibits growth of a larger species.
Mode-locking evolution in ring fiber lasers with tunable repetition rate.
Korobko, D A; Fotiadi, A A; Zolotovskii, I O
2017-09-04
We have applied a simple approach to analyze behavior of the harmonically mode-locked fiber laser incorporating an adjustable Mach-Zehnder interferometer (MZI). Our model is able to describe key features of the laser outputs and explore limitations of physical mechanisms responsible for laser operation at different pulse repetition rates tuned over a whole GHz range. At low repetition rates the laser operates as a harmonically mode-locked soliton laser triggered by a fast saturable absorber. At high repetition rates the laser mode-locking occurs due to dissipative four-wave mixing seeded by MZI and gain spectrum filtering. However, the laser stability in this regime is rather low due to poor mode selectivity provided by MZI that is able to support the desired laser operation just near the lasing threshold. The use of a double MZI instead of a single MZI could improve the laser stability and extends the range of the laser tunability. The model predicts a gap between two repetitive rate ranges where pulse train generation is not supported.
Adaptive quantization-parameter clip scheme for smooth quality in H.264/AVC.
Hu, Sudeng; Wang, Hanli; Kwong, Sam
2012-04-01
In this paper, we investigate the issues over the smooth quality and the smooth bit rate during rate control (RC) in H.264/AVC. An adaptive quantization-parameter (Q(p)) clip scheme is proposed to optimize the quality smoothness while keeping the bit-rate fluctuation at an acceptable level. First, the frame complexity variation is studied by defining a complexity ratio between two nearby frames. Second, the range of the generated bits is analyzed to prevent the encoder buffer from overflow and underflow. Third, based on the safe range of the generated bits, an optimal Q(p) clip range is developed to reduce the quality fluctuation. Experimental results demonstrate that the proposed Q(p) clip scheme can achieve excellent performance in quality smoothness and buffer regulation.
Fast and High Dynamic Range Imaging with Superconducting Tunnel Junction Detectors
NASA Astrophysics Data System (ADS)
Matsuo, Hiroshi
2014-08-01
We have demonstrated a combined test of the submillimeter-wave SIS photon detectors and GaAs-JFET cryogenic integrated circuits. A relatively large background photo-current can be read out by fast-reset integrating amplifiers. An integration time of 1 ms enables fast frame rate readout and large dynamic range imaging, with an expected dynamic range of 8,000 in 1 ms. Ultimate fast and high dynamic range performance of superconducting tunnel junction detectors (STJ) will be obtained when photon counting capabilities are employed. In the terahertz frequencies, when input photon rate of 100 MHz is measured, the photon bunching gives us enough timing resolution to be used as phase information of intensity fluctuation. Application of photon statistics will be a new tool in the terahertz frequency region. The design parameters of STJ terahertz photon counting detectors are discussed.
High dynamic range infrared radiometry and imaging
NASA Technical Reports Server (NTRS)
Coon, Darryl D.; Karunasiri, R. P. G.; Bandara, K. M. S. V.
1988-01-01
The use is described of cryogenically cooled, extrinsic silicon infrared detectors in an unconventional mode of operation which offers an unusually large dynamic range. The system performs intensity-to-frequency conversion at the focal plane via simple circuits with very low power consumption. The incident IR intensity controls the repetition rate of short duration output pulses over a pulse rate dynamic range of about 10(6). Theory indicates the possibility of monotonic and approx. linear response over the full dynamic range. A comparison between the theoretical and the experimental results shows that the model provides a reasonably good description of experimental data. Some measurements of survivability with a very intense IR source were made on these devices and found to be very encouraging. Evidence continues to indicate that some variations in interpulse time intervals are deterministic rather than probabilistic.
Patent ductus arteriosus in preterm infants: benefits of early surgical closure.
Fonseca, Elizabeth; Georgiev, Stanimir G; Gorenflo, Matthias; Loukanov, Tsvetomir S
2014-05-01
Patent ductus arteriosus in preterm neonates leads to significant morbidity. Surgery is indicated when pharmacological treatment fails or is contraindicated, but the optimal timing remains unclear. We retrospectively studied all 41 preterm neonates with symptomatic ductus arteriosus who underwent ligation between 1988 and 2009. We compared early complications rates and late neurological outcomes of patients operated on before 21 days of age with these operated on later. The median gestational age at birth was 26 weeks (range 23-31 weeks) and median weight at birth was 930 g (range 510-1500 g); 34 (82.9%) received pharmacological treatment before surgery. Fourteen (34.1%) patients underwent surgical closure before 21 days of age and 27 (65.9%) after 21 days. The 2 groups did not differ significantly in gestational age and weight at birth, but those operated on after 21 days received significantly more pharmacological treatment cycles. Patients in the early closure group had shorter intubation times: median 23 days (range 13-35 days) vs. 43 days (range 27-84 days; p < 0.001) and shorter neonatal intensive care unit stay: median 44 days (range 31-66 days) vs. 76 days (range 41-97 days; p < 0.001), with significantly lower rates of bronchopulmonary dysplasia, intraventricular hemorrhage, and acute renal failure, and significantly better neurological outcomes. Performing early ligation of symptomatic ductus arteriosus after unsuccessful pharmacological therapy in preterm neonates might lower complication rates and improve neurological outcome. Prospective randomized studies are needed to determine the optimal treatment.
NASA Astrophysics Data System (ADS)
Palamakumbura, Romesh; Robertson, Alastair; Kinnaird, Tim; van Calsteren, Peter; Kroon, Dick; Tait, Jenny
2016-04-01
The Kyrenia Range is a narrow E-W trending mountain range up to c. 180 km long by up to ca. 20 km wide, which is located <100 km south of the Anatolian orogenic plateau within the easternmost Mediterranean Sea. The Kyrenia Range structural lineament underwent tectonically driven uplift mainly during the Pleistocene in a setting dominated by incipient continental collision. The likely driver of the uplift was the collision of the Eratosthenes Seamount, an inferred promontory of north Africa, with a subduction zone located to the south of Cyprus. To help understand the tectonic processes driving the uplift of the Kyrenia Range several quantitative techniques have been used to date uplift-related terrace deposits exposed on the northern flank of the range. Uranium-series disequilibrium (U-series) dating provides ages of 127, 131 and 242 ka from solitary coral in shallow-marine deposits of the lowest terraces, whereas optically stimulated luminescence (OSL) dating gives ages of 53 and 76 ka from coastal aeolianite deposits. Prior to major tectonic uplift a shallow-marine carbonate-depositing sea existed in the vicinity of the Kyrenia Range. Some of the youngest pre-uplift marine carbonates yielded a reversed magnetic polarity, which constrains them as older than the last palaeomagnetic reversal (0.78 Ma). The combined evidence suggests that marine environments persisted into the Early Pleistocene, prior to major surface uplift of the Kyrenia Range lineament, which appears to have climaxed in the Mid-Pleistocene. The inferred uplift rates of the Kyrenia Range lineament range from >1.2 mm/yr during the Mid-Pleistocene to <0.2 mm/yr during the Late Pleistocene. The uplift rates of the Kyrenia Range appear to be, on average, significantly faster than those inferred for some adjacent regions of the Eastern Mediterranean during the Pleistocene (e.g. Lebanon coast; Anatolian plateau southern margin). The new data also suggest that the Kyrenia Range was uplifted contemporaneously with the ophiolitic Troodos Massif in southern Cyprus, which is in keeping with the model of regional-scale collision of the Eratosthenes Seamount with the Cyprus trench. The uplift of the Kyrenia Range lineament took place directly adjacent to the southern margin of the much larger Anatolian orogenic plateau, which was also mainly uplifted during the Pleistocene. The timing and processes involved in the uplift of the Kyrenia Range lineament are relevant to long-term processes of continental accretion and plateau uplift. On a longer timescale, the uplift of the Kyrenia Range in an incipient collisional setting can be seen as a step towards final accretion into a larger Anatolian orogenic plateau as collision intensifies. Terranes similar to the Kyrenia Range lineament may therefore exist embedded within the uplifted margins of orogenic plateaus in other areas of the world (e.g. southern Tibet).
Selonen, Salla; Setälä, Heikki
2015-06-15
The effects of shooting-derived lead (Pb) on the structure and functioning of a forest ecosystem, and the recovery of the ecosystem after range abandonment were studied at an active shotgun shooting range, an abandoned shooting range where shooting ceased 20 years earlier and an uncontaminated control site. Despite numerous lead-induced changes in the soil food web, soil processes were only weakly related to soil food web composition. However, decomposition of Scots pine (Pinus sylvestris) needle litter was retarded at the active shooting range, and microbial activity, microbial biomass and the rate of decomposition of Pb-contaminated grass litter decreased with increasing soil Pb concentrations. Tree (P. sylvestris) radial growth was suppressed at the active shooting range right after shooting activities started. In contrast, the growth of pines improved at the abandoned shooting range after the cessation of shooting, despite reduced nitrogen and phosphorus contents of the needles. Higher litter degradation rates and lower Pb concentrations in the topmost soil layer at the abandoned shooting range suggest gradual recovery after range abandonment. Our findings suggest that functions in lead-contaminated coniferous forest ecosystems depend on the successional stage of the forest as well as the time since the contamination source has been eliminated, which affects, e.g., the vertical distribution of the contaminant in the soil. However, despite multiple lead-induced changes throughout the ecosystem, the effects were rather weak, indicating high resistance of coniferous forest ecosystems to this type of stress. Copyright © 2015 Elsevier B.V. All rights reserved.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-15
... Albuquerque, NM, and El Paso, TX, wage areas to White Sands Missile Range. DATES: We must receive comments on... because the Department of Defense now refers to it as that White Sands Missile Range. OPM announced these... not include White Sands Missile Range portion) Los Alamos Mora Quay Rio Arriba Roosevelt San Miguel...
Interacting scales and energy transfer in isotropic turbulence
NASA Technical Reports Server (NTRS)
Zhou, YE
1993-01-01
The dependence of the energy transfer process on the disparity of the interacting scales is investigated in the inertial and far-dissipation ranges of isotropic turbulence. The strategy for generating the simulated flow fields and the choice of a disparity parameter to characterize the scaling of the interactions is discussed. The inertial range is found to be dominated by relatively local interactions, in agreement with the Kolmogorov assumption. The far-dissipation is found to be dominated by relatively non-local interactions, supporting the classical notion that the far-dissipation range is slaved to the Kolmogorov scales. The measured energy transfer is compared with the classical models of Heisenberg, Obukhov, and the more detailed analysis of Tennekes and Lumley. The energy transfer statistics measured in the numerically simulated flows are found to be nearly self-similar for wave numbers in the inertial range. Using the self-similar form measured within the limited scale range of the simulation, an 'ideal' energy transfer function and the corresponding energy flux rate for an inertial range of infinite extent are constructed. From this flux rate, the Kolmogorov constant is calculated to be 1.5, in excellent agreement with experiments.
Experimental Investigation of Diffuser Hub Injection to Improve Centrifugal Compressor Stability
NASA Technical Reports Server (NTRS)
Skoch, Gary J.
2004-01-01
Results from a series of experiments to investigate whether centrifugal compressor stability could be improved by injecting air through the diffuser hub surface are reported. The research was conducted in a 4:1 pressure ratio centrifugal compressor configured with a vane-island diffuser. Injector nozzles were located just upstream of the leading edge of the diffuser vanes. Nozzle orientations were set to produce injected streams angled at 8, 0 and +8 degrees relative to the vane mean camber line. Several injection flow rates were tested using both an external air supply and recirculation from the diffuser exit. Compressor flow range did not improve at any injection flow rate that was tested. Compressor flow range did improve slightly at zero injection due to the flow resistance created by injector openings on the hub surface. Leading edge loading and semi-vaneless space diffusion showed trends similar to those reported earlier from shroud surface experiments that did improve compressor flow range. Opposite trends are seen for hub injection cases where compressor flow range decreased. The hub injection data further explain the range improvement provided by shroud-side injection and suggest that different hub-side techniques may produce range improvement in centrifugal compressors.
Image dissector camera system study
NASA Technical Reports Server (NTRS)
Howell, L.
1984-01-01
Various aspects of a rendezvous and docking system using an image dissector detector as compared to a GaAs detector were discussed. Investigation into a gimbled scanning system is also covered and the measured video response curves from the image dissector camera are presented. Rendezvous will occur at ranges greater than 100 meters. The maximum range considered was 1000 meters. During docking, the range, range-rate, angle, and angle-rate to each reflector on the satellite must be measured. Docking range will be from 3 to 100 meters. The system consists of a CW laser diode transmitter and an image dissector receiver. The transmitter beam is amplitude modulated with three sine wave tones for ranging. The beam is coaxially combined with the receiver beam. Mechanical deflection of the transmitter beam, + or - 10 degrees in both X and Y, can be accomplished before or after it is combined with the receiver beam. The receiver will have a field-of-view (FOV) of 20 degrees and an instantaneous field-of-view (IFOV) of two milliradians (mrad) and will be electronically scanned in the image dissector. The increase in performance obtained from the GaAs photocathode is not needed to meet the present performance requirements.
Abnormal ranges of vital signs in children in Japanese prehospital settings.
Nosaka, Nobuyuki; Muguruma, Takashi; Knaup, Emily; Tsukahara, Kohei; Enomoto, Yuki; Kaku, Noriyuki
2015-10-01
The revised Fire Service Law obliges each prefectural government in Japan to establish a prehospital acuity scale. The Foundation for Ambulance Service Development (FASD) created an acuity scale for use as a reference. Our preliminary survey revealed that 32 of 47 prefectures directly applied the FASD scale for children. This scale shows abnormal ranges of heart rate and respiratory rate in young children. This study aimed to evaluate the validity of the abnormal ranges on the FASD scale to assess its overall performance for triage purposes in paediatric patients. We evaluated the validity of the ranges by comparing published centile charts for these vital signs with records of 1,296 ambulance patients. A large portion of the abnormal ranges on the scale substantially overlapped with the normal centile charts. Triage decisions using the FASD scale of vital signs properly classified 22% ( n = 287) of children. The sensitivity and specificity for high urgency were as high as 91% (95% confidence interval, 82-96%) and as low as 18% (95% confidence interval, 16-20%). We found there is room for improvement of the abnormal ranges on the FASD scale.
Acceptable range of speech level in noisy sound fields for young adults and elderly persons.
Sato, Hayato; Morimoto, Masayuki; Ota, Ryo
2011-09-01
The acceptable range of speech level as a function of background noise level was investigated on the basis of word intelligibility scores and listening difficulty ratings. In the present study, the acceptable range is defined as the range that maximizes word intelligibility scores and simultaneously does not cause a significant increase in listening difficulty ratings from the minimum ratings. Listening tests with young adult and elderly listeners demonstrated the following. (1) The acceptable range of speech level for elderly listeners overlapped that for young listeners. (2) The lower limit of the acceptable speech level for both young and elderly listeners was 65 dB (A-weighted) for noise levels of 40 and 45 dB (A-weighted), a level with a speech-to-noise ratio of +15 dB for noise levels of 50 and 55 dB, and a level with a speech-to-noise ratio of +10 dB for noise levels from 60 to 70 dB. (3) The upper limit of the acceptable speech level for both young and elderly listeners was 80 dB for noise levels from 40 to 55 dB and 85 dB or above for noise levels from 55 to 70 dB. © 2011 Acoustical Society of America
NASA Astrophysics Data System (ADS)
Chen, S. T.; Chen, W. S.
2016-12-01
Since late Pleistocene, the Coastal Range (Philippine Sea plate) collided and overridden on the Central Range (Eurasian Plate) along the Longitudinal Valley Fault. Therefore, the Coastal Range is exposed widely the late Pleistocene-Holocene marine and fluvial terraces caused by the tectonic uplift. Based on the estimation of paleosea-level elevations (Δh), depositional paleodepth, altitude distribution of Holocene deposits (D), altitude of outcrops (H), and 14C dating of marine deposits (t), the uplift rate (=(Δh+H +d-D)/t) is about 5-10 mm/yr in the southern Coastal Range. In this study, we suggest through field logging that the deposits can be divided into alluvial, foreshore (intertidal), shoreface, and offshore environments. In Dulan area in the southern Coastal Range, the uplift rate was 6-7 mm/yr during 16,380-10,000 cal yr BP and 3-4 mm/yr after 7,000 cal yr BP. Results from the Dulan Coastal alluvial-fan system can be divided into five depositional stages: (1) 16,380-14,300 cal yr BP: The rate of global sea level rise (SLR) has averaged about 6-7 mm/yr, similar to the tectonic uplift rate. In this stage, the bedrock was eroded and formed a wide wave-cut platform. (2) 14,300-10,000 cal yr BP: SLR of about 14 mm/yr that was faster than tectonic uplift rate of 6-7 mm/yr. As a result of transgression, the beach-lagoon deposits about 5 m thick were unconformably overlain on the wave-cut platform. (3) 10,000-8,200 cal yr BP: The ongoing sea level rise (SLR: 11 mm/yr), the lagoon deposits were overlain by an offshore slump deposits representing a gradual deepening of the depositional environment. (4) 8,200-7,930 cal yr BP (SLR: 6-7 mm/yr): The tectonic uplift rate may occur at similar SLR. The alluvial-fan deposits have prograded over the shallow marine deposits. (5) After 7,000 cal yr BP (SLR: 1-0 mm/yr): SLR was much slower than tectonic uplift rate of 3-4 mm/yr. Thus, Holocene marine terraces are extensively developed in the coastal region, showing that the Holocene marine deposits rest above the fluvial deposits. The crustal high uplift rates of relative sea-level changes led to form a well-developed multiple Holocene marine terraces.
Unusually low rates of slip on the Santa Rosa Range fault zone, northern Nevada
Personius, S.F.; Mahan, S.A.
2005-01-01
The Santa Rosa Range fault zone (SRRFZ) is one of the most topographically prominent normal fault systems in the northern Basin and Range province of the western United States. It has been assigned high rates of vertical slip by others and has been identified as a possible site of the future extension of the central Nevada seismic belt (CNSB). We use detailed trench mapping and luminescence dating to estimate displacements and timing of the last several large-magnitude paleoearthquakes on the southern part of the SRRFZ at a trench site near Orovada, Nevada. Coseismic vertical displacements ranged from 1 to 2.8 m for each of the last four events. Luminescence ages provide time limits for the last three events of 125-155 ka, 90-108 ka, and 11-16 ka. These data yield recurrence intervals of 17-65 k.y. and 74-97 k.y. and an elapsed time of 11-16 k.y. since the youngest event. Slip-rate determinations at the Orovada site are complicated by multiple fault strands, but rates calculated from a variety of data are surprisingly low (0.01-0.16 mm/yr), given the topographic prominence of the Santa Rosa Range. A lack of compelling patterns in a comparison of paleoseismic parameters indicate that the SRRFZ is no more likely a location for a large-magnitude earthquake than previously identified seismic gaps or along faults that lie directly north of the CNSB.
Hoganson, David M; Hinkel, Cameron J; Chen, Xiaomin; Agarwal, Ramesh K; Shenoy, Surendra
2014-01-01
Stenosis in a vascular access circuit is the predominant cause of access dysfunction. Hemodynamic significance of a stenosis identified by angiography in an access circuit is uncertain. This study utilizes computational fluid dynamics (CFD) to model flow through arteriovenous fistula to predict the functional significance of stenosis in vascular access circuits. Three-dimensional models of fistulas were created with a range of clinically relevant stenoses using SolidWorks. Stenoses diameters ranged from 1.0 to 3.0 mm and lengths from 5 to 60 mm within a fistula diameter of 7 mm. CFD analyses were performed using a blood model over a range of blood pressures. Eight patient-specific stenoses were also modeled and analyzed with CFD and the resulting blood flow calculations were validated by comparison with brachial artery flow measured by duplex ultrasound. Predicted flow rates were derived from CFD analysis of a range of stenoses. These stenoses were modeled by CFD and correlated with the ultrasound measured flow rate through the fistula of eight patients. The calculated flow rate using CFD correlated within 20% of ultrasound measured flow for five of eight patients. The mean difference was 17.2% (ranged from 1.3% to 30.1%). CFD analysis-generated flow rate tables provide valuable information to assess the functional significance of stenosis detected during imaging studies. The CFD study can help in determining the clinical relevance of a stenosis in access dysfunction and guide the need for intervention.
Species traits and climate velocity explain geographic range shifts in an ocean-warming hotspot.
Sunday, Jennifer M; Pecl, Gretta T; Frusher, Stewart; Hobday, Alistair J; Hill, Nicole; Holbrook, Neil J; Edgar, Graham J; Stuart-Smith, Rick; Barrett, Neville; Wernberg, Thomas; Watson, Reg A; Smale, Dan A; Fulton, Elizabeth A; Slawinski, Dirk; Feng, Ming; Radford, Ben T; Thompson, Peter A; Bates, Amanda E
2015-09-01
Species' ranges are shifting globally in response to climate warming, with substantial variability among taxa, even within regions. Relationships between range dynamics and intrinsic species traits may be particularly apparent in the ocean, where temperature more directly shapes species' distributions. Here, we test for a role of species traits and climate velocity in driving range extensions in the ocean-warming hotspot of southeast Australia. Climate velocity explained some variation in range shifts, however, including species traits more than doubled the variation explained. Swimming ability, omnivory and latitudinal range size all had positive relationships with range extension rate, supporting hypotheses that increased dispersal capacity and ecological generalism promote extensions. We find independent support for the hypothesis that species with narrow latitudinal ranges are limited by factors other than climate. Our findings suggest that small-ranging species are in double jeopardy, with limited ability to escape warming and greater intrinsic vulnerability to stochastic disturbances. © 2015 John Wiley & Sons Ltd/CNRS.
Partial stapled hemorrhoidopexy: a minimally invasive technique for hemorrhoids.
Lin, Hong-Cheng; He, Qiu-Lan; Ren, Dong-Lin; Peng, Hui; Xie, Shang-Kui; Su, Dan; Wang, Xiao-Xue
2012-09-01
This study was designed to assess the safety, efficacy, and postoperative outcomes of partial stapled hemorrhoidopexy (PSH). A prospective study was conducted between February and March 2010. PSH was performed with single-window anoscopes for single isolated hemorrhoids, bi-window anoscopes for two isolated hemorrhoids, and tri-window anoscopes for three isolated hemorrhoids or circumferential hemorrhoids. The data pertaining to demographics, preoperative characteristics and postoperative outcomes were collected and analyzed. Forty-four eligible patients underwent PSH. Single-window anoscopes were used in 2 patients, and bi- and tri-window anoscopes in 6 and 36 patients. The blood loss in patients with single-window, bi-window, and tri-window anoscopes was 6.0 ml (range 5.0-7.0 ml), 5.0 ml (range 5.0-6.5 ml), and 5.0 ml (4.5-14.5 ml) (P = 0.332). The mean postoperative visual analog scale score for pain was 3 (range, 1-4), 2 (range 1-4), 3 (range 2-6), 1 (range 0-3), 1 (range 0-2) and 2 (range 2-4) at 12 h, days 1, 2, 3, and 7, and at first defecation. The rate of urgency was 9.1%. No patients developed anal incontinence or stenosis. The 1-year recurrence rate of prolapsing hemorrhoids was 2.3%. Partial stapled hemorrhoidopexy appears to be a safe and effective technique for grade III-IV hemorrhoids. Encouragingly, PSH is associated with mild postoperative pain, few urgency episodes, and no stenosis or anal incontinence.
Huang, Rong Fung; Chen, Jia-Kun; Lin, Jyun-Hua
2015-01-01
The flow and spillage characteristics of an inclined quad-vortex (IQV) range hood subject to the influence of drafts from various directions were studied. The laser-assisted smoke flow visualization technique was used to reveal the flow characteristics, and the tracer-gas (sulfur hexafluoride) concentration detection method was used to indicate the quantitative values of the capture efficiency of the hood. It was found that the leakage mechanisms of the IQV range hood are closely related to the flow characteristics. A critical draft velocity of about 0.5 m/s and a critical face velocity of about 0.25 m/s for the IQV range hood were found. When the IQV range hood was influenced by a draft with a velocity larger than the critical draft velocity, the spillage of pollutants became significant and the pollutant spillage rate increased with increasing draft velocity. At draft velocities less than or equal to the critical value, no containment leakages induced by the turbulence diffusion, reverse flow, or boundary-layer separation were observed, and the capture efficiency was about 100%. The IQV range hood exhibited a high ability to resist the influences of lateral and frontal drafts. The capture efficiency of the IQV range hood operated at the suction flow rate 5 to 9 m(3)/min is higher than that of the conventional range hood operated at 11 to 15 m(3)/min.
Effects of high density on spacing behaviour and reproduction in Akodon azarae: A fencing experiment
NASA Astrophysics Data System (ADS)
Ávila, Belén; Bonatto, Florencia; Priotto, José; Steinmann, Andrea R.
2016-01-01
We studied the short term spacing behavioural responses of Pampean grassland mouse (Akodon azarae) with regard to population density in four 0.25 ha enclosures (two control and two experimental) in the 2011 breeding season. Based on the hypothesis that A. azarae breeding females exhibit spacing behaviour, and breeding males show a fusion spatial response, we tested the following predictions: (1) home range size and intrasexual overlap degree of females are independent of population density values; (2) at high population density, home range size of males decreases and the intrasexual home range overlap degree increases. To determine if female reproductive success decreases at high population density, we analyzed pregnancy rate, size and weight of litters, and period until fecundation in both low and high enclosure population density. We found that both males and females varied their home range size in relation to population density. Although male home ranges were always bigger than those of females in populations with high density, home range sizes of both sexes decreased. Females kept exclusive home ranges independent of density values meanwhile males decreased home range overlap in high breeding density populations. Although females produced litters of similar size in both treatments, weight of litter, pregnant rate and period until fecundation varied in relation to population density. Our results did not support the hypothesis that at high density females of A. azarae exhibit spacing behaviour neither that males exhibit a fusion spatial response.
Space-Based Range Safety and Future Space Range Applications
NASA Technical Reports Server (NTRS)
Whiteman, Donald E.; Valencia, Lisa M.; Simpson, James C.
2005-01-01
The National Aeronautics and Space Administration (NASA) Space-Based Telemetry and Range Safety (STARS) study is a multiphase project to demonstrate the performance, flexibility and cost savings that can be realized by using space-based assets for the Range Safety [global positioning system (GPS) metric tracking data, flight termination command and range safety data relay] and Range User (telemetry) functions during vehicle launches and landings. Phase 1 included flight testing S-band Range Safety and Range User hardware in 2003 onboard a high-dynamic aircraft platform at Dryden Flight Research Center (Edwards, California, USA) using the NASA Tracking and Data Relay Satellite System (TDRSS) as the communications link. The current effort, Phase 2, includes hardware and packaging upgrades to the S-band Range Safety system and development of a high data rate Ku-band Range User system. The enhanced Phase 2 Range Safety Unit (RSU) provided real-time video for three days during the historic Global Flyer (Scaled Composites, Mojave, California, USA) flight in March, 2005. Additional Phase 2 testing will include a sounding rocket test of the Range Safety system and aircraft flight testing of both systems. Future testing will include a flight test on a launch vehicle platform. This paper discusses both Range Safety and Range User developments and testing with emphasis on the Range Safety system. The operational concept of a future space-based range is also discussed.
Space-Based Range Safety and Future Space Range Applications
NASA Technical Reports Server (NTRS)
Whiteman, Donald E.; Valencia, Lisa M.; Simpson, James C.
2005-01-01
The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to demonstrate the performance, flexibility and cost savings that can be realized by using space-based assets for the Range Safety (global positioning system metric tracking data, flight termination command and range safety data relay) and Range User (telemetry) functions during vehicle launches and landings. Phase 1 included flight testing S-band Range Safety and Range User hardware in 2003 onboard a high-dynamic aircraft platform at Dryden Flight Research Center (Edwards, California) using the NASA Tracking and Data Relay Satellite System as the communications link. The current effort, Phase 2, includes hardware and packaging upgrades to the S-band Range Safety system and development of a high data rate Ku-band Range User system. The enhanced Phase 2 Range Safety Unit provided real-time video for three days during the historic GlobalFlyer (Scaled Composites, Mojave, California) flight in March, 2005. Additional Phase 2 testing will include a sounding rocket test of the Range Safety system and aircraft flight testing of both systems. Future testing will include a flight test on a launch vehicle platform. This report discusses both Range Safety and Range User developments and testing with emphasis on the Range Safety system. The operational concept of a future space-based range is also discussed.
Variations in teenage birth rates, 1991-98: national and state trends.
Ventura, S J; Curtin, S C; Mathews, T J
2000-04-24
This report presents national birth rates for teenagers for 1991-98 and the percent change, 1991-98. State-specific teenage birth rates by age, race, and Hispanic origin for 1991 and 1998 and the percent change, 1991 to 1998, are also presented. Tabular and graphical descriptions of the trends in teenage birth rates for the Nation and each State, by age group, race, and Hispanic origin of the mother, are discussed. Birth rates for teenagers 15-19 years declined nationally between 1991 and 1998 for all age and race and Hispanic origin populations, with the steepest declines recorded for black teenagers. State-specific rates fell significantly in all States for ages 15-19 years; declines ranged from 10 to 38 percent. In general, rates by State fell more for younger than for older teenagers, ranging by State from 10 to 46 percent for ages 15-17 years. Statistically significant reductions for older teenagers ranged from 3 to 39 percent. Reductions by State were largest for black teenagers 15-19 years, with rates falling 30 percent or more in 15 States. Among the factors accounting for these declines are decreased sexual activity, increases in condom use, and the adoption of the implant and injectable contraceptives.
Species biogeography predicts drought responses in a seasonally dry tropical forest
NASA Astrophysics Data System (ADS)
Schwartz, N.; Powers, J. S.; Vargas, G.; Xu, X.; Smith, C. M.; Brodribb, T.; Werden, L. K.; Becknell, J.; Medvigy, D.
2017-12-01
The timing, distribution, and amount of rainfall in the seasonal tropics have shifted in recent years, with consequences for seasonally dry tropical forests (SDTF). SDTF are sensitive to changing rainfall regimes and drought conditions, but sensitivity to drought varies substantially across species. One potential explanation of species differences is that species that experience dry conditions more frequently throughout their range will be better able to cope with drought than species from wetter climates, because species from drier climates will be better adapted to drought. An El-Niño induced drought in 2015 presented an opportunity to assess species-level differences in mortality in SDTF, and to ask whether the ranges of rainfall conditions species experience and the average rainfall regimes in species' ranges predict differences in mortality rates in Costa Rican SDTF. We used field plot data from northwest Costa Rica to determine species' level mortality rates. Mortality rates ranged substantially across species, with some species having no dead individuals to as high as 50% mortality. To quantify rainfall conditions across species' ranges, we used species occurrence data from the Global Biodiversity Information Facility, and rainfall data from the Chelsa climate dataset. We found that while the average and range of mean annual rainfall across species ranges did not predict drought-induced mortality in the field plots, across-range averages of the seasonality index, a measure of rainfall seasonality, was strongly correlated with species-level drought mortality (r = -0.62, p < 0.05), with species from more strongly seasonal climates experiencing less severe drought mortality. Furthermore, we found that the seasonality index was a stronger predictor of mortality than any individual functional trait we considered. This result shows that species' biogeography may be an important factor for how species will respond to future drought, and may be a more integrative predictor than individual functional traits.
Zhang, Ling; Zhang, Yaojun; Wang, Hong; Zou, Jianwen; Siemann, Evan
2013-01-01
Two mechanisms that have been proposed to explain success of invasive plants are unusual biotic interactions, such as enemy release or enhanced mutualisms, and increased resource availability. However, while these mechanisms are usually considered separately, both may be involved in successful invasions. Biotic interactions may be positive or negative and may interact with nutritional resources in determining invasion success. In addition, the effects of different nutrients on invasions may vary. Finally, genetic variation in traits between populations located in introduced versus native ranges may be important for biotic interactions and/or resource use. Here, we investigated the roles of soil biota, resource availability, and plant genetic variation using seedlings of Triadica sebifera in an experiment in the native range (China). We manipulated nitrogen (control or 4 g/m(2)), phosphorus (control or 0.5 g/m(2)), soil biota (untreated or sterilized field soil), and plant origin (4 populations from the invasive range, 4 populations from the native range) in a full factorial experiment. Phosphorus addition increased root, stem, and leaf masses. Leaf mass and height growth depended on population origin and soil sterilization. Invasive populations had higher leaf mass and growth rates than native populations did in fresh soil but they had lower, comparable leaf mass and growth rates in sterilized soil. Invasive populations had higher growth rates with phosphorus addition but native ones did not. Soil sterilization decreased specific leaf area in both native and exotic populations. Negative effects of soil sterilization suggest that soil pathogens may not be as important as soil mutualists for T. sebifera performance. Moreover, interactive effects of sterilization and origin suggest that invasive T. sebifera may have evolved more beneficial relationships with the soil biota. Overall, seedlings from the invasive range outperformed those from the native range, however, an absence of soil biota or low phosphorus removed this advantage.
Zhang, Ling; Zhang, Yaojun; Wang, Hong; Zou, Jianwen; Siemann, Evan
2013-01-01
Two mechanisms that have been proposed to explain success of invasive plants are unusual biotic interactions, such as enemy release or enhanced mutualisms, and increased resource availability. However, while these mechanisms are usually considered separately, both may be involved in successful invasions. Biotic interactions may be positive or negative and may interact with nutritional resources in determining invasion success. In addition, the effects of different nutrients on invasions may vary. Finally, genetic variation in traits between populations located in introduced versus native ranges may be important for biotic interactions and/or resource use. Here, we investigated the roles of soil biota, resource availability, and plant genetic variation using seedlings of Triadica sebifera in an experiment in the native range (China). We manipulated nitrogen (control or 4 g/m2), phosphorus (control or 0.5 g/m2), soil biota (untreated or sterilized field soil), and plant origin (4 populations from the invasive range, 4 populations from the native range) in a full factorial experiment. Phosphorus addition increased root, stem, and leaf masses. Leaf mass and height growth depended on population origin and soil sterilization. Invasive populations had higher leaf mass and growth rates than native populations did in fresh soil but they had lower, comparable leaf mass and growth rates in sterilized soil. Invasive populations had higher growth rates with phosphorus addition but native ones did not. Soil sterilization decreased specific leaf area in both native and exotic populations. Negative effects of soil sterilization suggest that soil pathogens may not be as important as soil mutualists for T. sebifera performance. Moreover, interactive effects of sterilization and origin suggest that invasive T. sebifera may have evolved more beneficial relationships with the soil biota. Overall, seedlings from the invasive range outperformed those from the native range, however, an absence of soil biota or low phosphorus removed this advantage. PMID:24023930
Potsaid, Benjamin; Baumann, Bernhard; Huang, David; Barry, Scott; Cable, Alex E.; Schuman, Joel S.; Duker, Jay S.; Fujimoto, James G.
2011-01-01
We demonstrate ultrahigh speed swept source/Fourier domain ophthalmic OCT imaging using a short cavity swept laser at 100,000–400,000 axial scan rates. Several design configurations illustrate tradeoffs in imaging speed, sensitivity, axial resolution, and imaging depth. Variable rate A/D optical clocking is used to acquire linear-in-k OCT fringe data at 100kHz axial scan rate with 5.3um axial resolution in tissue. Fixed rate sampling at 1 GSPS achieves a 7.5mm imaging range in tissue with 6.0um axial resolution at 100kHz axial scan rate. A 200kHz axial scan rate with 5.3um axial resolution over 4mm imaging range is achieved by buffering the laser sweep. Dual spot OCT using two parallel interferometers achieves 400kHz axial scan rate, almost 2X faster than previous 1050nm ophthalmic results and 20X faster than current commercial instruments. Superior sensitivity roll-off performance is shown. Imaging is demonstrated in the human retina and anterior segment. Wide field 12×12mm data sets include the macula and optic nerve head. Small area, high density imaging shows individual cone photoreceptors. The 7.5mm imaging range configuration can show the cornea, iris, and anterior lens in a single image. These improvements in imaging speed and depth range provide important advantages for ophthalmic imaging. The ability to rapidly acquire 3D-OCT data over a wide field of view promises to simplify examination protocols. The ability to image fine structures can provide detailed information on focal pathologies. The large imaging range and improved image penetration at 1050nm wavelengths promises to improve performance for instrumentation which images both the retina and anterior eye. These advantages suggest that swept source OCT at 1050nm wavelengths will play an important role in future ophthalmic instrumentation. PMID:20940894
Shock absorber operates over wide range
NASA Technical Reports Server (NTRS)
Creasy, W. K.; Jones, J. C.
1965-01-01
Piston-type hydraulic shock absorber, with a metered damping system, operates over a wide range of kinetic energy loading rates. It is used for absorbing shock and vibration on mounted machinery and heavy earth-moving equipment.
Boeye, Jeroen; Travis, Justin M J; Stoks, Robby; Bonte, Dries
2013-02-01
Species can either adapt to new conditions induced by climate change or shift their range in an attempt to track optimal environmental conditions. During current range shifts, species are simultaneously confronted with a second major anthropogenic disturbance, landscape fragmentation. Using individual-based models with a shifting climate window, we examine the effect of different rates of climate change on the evolution of dispersal distances through changes in the genetically determined dispersal kernel. Our results demonstrate that the rate of climate change is positively correlated to the evolved dispersal distances although too fast climate change causes the population to crash. When faced with realistic rates of climate change, greater dispersal distances evolve than those required for the population to keep track of the climate, thereby maximizing population size. Importantly, the greater dispersal distances that evolve when climate change is more rapid, induce evolutionary rescue by facilitating the population in crossing large gaps in the landscape. This could ensure population persistence in case of range shifting in fragmented landscapes. Furthermore, we highlight problems in using invasion speed as a proxy for potential range shifting abilities under climate change.
Scanning AC Nanocalorimetry and Its Applications
NASA Astrophysics Data System (ADS)
Xiao, Kechao
This thesis presents an AC nanocalorimetry technique that enables calorimetry measurements on very small quantities of materials over a wide range of scanning rates (from isothermal to 3x10. 3 K/s), temperatures(up to 1200 K), and environments. Such working range bridges the gap between traditional scanning calorimetry of bulk materials and nanocalorimetry. The method relies on a micromachined nanocalorimeter with negligible thermal lags between heater, thermometer, and sample. The ability to perform calorimetry measurements over such a broad range of scanning rates makes it an ideal tool to characterize the kinetics of phase transformations, reactions at elevated temperatures or to explore the behavior of materials far from equilibrium. We demonstrate the technique by performing measurements on thin-film samples of Sn, In, and Bi with thicknesses ranging from 100 to 300 nm. The experimental heat capacities and melting temperatures agree well with literature values. The measured heat capacities are insensitive to the applied AC frequency, scan rate, and heat loss to the environment over a broad range of experimental conditions. The dynamic range of scanning AC nanocalorimetry enables the combination of nanocalorimetry with in-situ x-ray diffraction (XRD) to facilitate interpretation of the calorimetry measurements. Time-resolved XRD during in-situ operation of nanocalorimetry sensors using intense, high-energy synchrotron radiation allows unprecedented characterization of thermal and structural material properties. We demonstrate this experiment with detailed characterization of the melting and solidification of elemental Bi, In and Sn thin-film samples, using heating and cooling rates up to 300 K/s. By combining scanning DC and AC nano-calorimetry techniques, we study the nucleation behavior of undercooled liquid Bi at cooling rates ranging from 10. 1 to 10. 4 K/s. Upon initial melting, the Bi thin-film sample breaksup into isolated islands. The number of islands in a typical sample is sufficiently large that highly repeatable nucleation behavior is observed, despite the stochastic nature of the nucleation process. We establish a data reduction technique to evaluate the nucleation rate from DC and AC calorimetry results. The results show that the driving force for the nucleation of melted Bi is well described by classical nucleation theory over a wide range of cooling rates. The proposed technique provides a unique and efficient way to examine nucleation kinetics with cooling rates over several orders of magnitude. The technique is quite general and can be used to evaluate reaction kinetics in other materials. Lastly, we apply the scanning AC nanocalorimetry technique to study solid-gas phase reactions by measuring the change in heat capacity of a sample during reaction. We apply this approach to evaluate the oxidation kinetics of thin-film samples of zirconium in air. The results confirm parabolic oxidation kinetics with an activation energy of 0.59+/-0.03 eV. The nano-calorimetry measurements were performed using a device that contains an array of micromachined nano-calorimeter sensors in an architecture designed for combinatorial studies. We demonstrate that the oxidation kinetics can be quantified using a single sample, thus enabling high-throughput mapping of the composition-dependence of the reaction rate.
The growth and population dynamics of seagrass Thalassia hemprichii in Suli Waters, Ambon Island
NASA Astrophysics Data System (ADS)
Tupan, C. I.; Uneputty, Pr A.
2017-10-01
The objectives of the research were to determined growth of rhizome, age structure, recruitment rate, and mortality rate of Thalassia hemprichii. Data were collected by using reconstruction technique which the measurements were based on past growth history. The age of seagrass was based on plastochrone interval. The recruitment rate was estimated by age structure of living shoots while mortality rate was estimated by age structure of dead shoots. The research was conducted on coastal waters of Suli where divided into two stations with different substrates, namely mixed substrates of sand and mud (S1) and mixed substrates of sand and coral fragment (S2). The growth rate of horizontal rhizome ranged from 4.15-8.68 cm.year-1 whereas the growth rate of vertical rhizome was 1.11-1.16 cm.year-1. The average age of T. hemprichii varied between 3.22-4.15 years. The youngest shoots were found at age 0.38 years and the oldest shoots were 7.82 years. Distribution of age was polymodal which reflecting cohort. The recruitment rate ranged from 0.23-0.54 year-1. Otherwise, the mortality rate ranged from 0.21-0.26 year-1.Seagrass population of T. hemprichii in Suli Waters indicated an increasing condition which shown by higher recruitment rate than mortality rate.
Earthquake Clustering on Normal Faults: Insight from Rate-and-State Friction Models
NASA Astrophysics Data System (ADS)
Biemiller, J.; Lavier, L. L.; Wallace, L.
2016-12-01
Temporal variations in slip rate on normal faults have been recognized in Hawaii and the Basin and Range. The recurrence intervals of these slip transients range from 2 years on the flanks of Kilauea, Hawaii to 10 kyr timescale earthquake clustering on the Wasatch Fault in the eastern Basin and Range. In addition to these longer recurrence transients in the Basin and Range, recent GPS results there also suggest elevated deformation rate events with recurrence intervals of 2-4 years. These observations suggest that some active normal fault systems are dominated by slip behaviors that fall between the end-members of steady aseismic creep and periodic, purely elastic, seismic-cycle deformation. Recent studies propose that 200 year to 50 kyr timescale supercycles may control the magnitude, timing, and frequency of seismic-cycle earthquakes in subduction zones, where aseismic slip transients are known to play an important role in total deformation. Seismic cycle deformation of normal faults may be similarly influenced by its timing within long-period supercycles. We present numerical models (based on rate-and-state friction) of normal faults such as the Wasatch Fault showing that realistic rate-and-state parameter distributions along an extensional fault zone can give rise to earthquake clusters separated by 500 yr - 5 kyr periods of aseismic slip transients on some portions of the fault. The recurrence intervals of events within each earthquake cluster range from 200 to 400 years. Our results support the importance of stress and strain history as controls on a normal fault's present and future slip behavior and on the characteristics of its current seismic cycle. These models suggest that long- to medium-term fault slip history may influence the temporal distribution, recurrence interval, and earthquake magnitudes for a given normal fault segment.
Department of Defense Operational Range Sustainability through Management of Munitions Constituents
2014-04-01
the MCs resulting from military training activities on ranges, to characterize the environmental deposition of MCs on military ranges, and to develop...technologies to manage or contain MCs in soil and groundwater. The results from these efforts can be found in numerous technical reports and journal...groundwater flow rate (if available), aquifer characteristics, monitoring well logs (if available), and historical sampling and analytical results
Precision Strike 2008 Summer Forum
2008-01-11
extended ranges, 360--mounted and dismounted Technical fire direction and limited tactical fire direction on all delivery systems Delivery systems that...can rapidly emplace/displace with high rates of fire Accurate on demand, meteorological data to delivery system ranges All munitions with less than 50M...CEP at all ranges Munitions that provide a variety of effects in any environment To achieve this, Field Artillery needs these “enablers” Target
NASA Astrophysics Data System (ADS)
Anderson, Suzanne P.; Foster, Melissa A.; Anderson, Scott W.; Dühnforth, Miriam; Anderson, Robert S.
2015-04-01
Erosion rates are expected vary with lithology, climate, and topographic slope, yet assembling these variations for an entire landscape is rarely done. The Front Range of the southern Rocky Mountains in Colorado, USA, exhibits contrasts in all three parameters. The range comprises ~2300 m in relief from the Plains to the crags of the Continental Divide. Its abrupt mountain front coincides closely with the boundary between marine sedimentary rocks to the east and Proterozoic crystalline rocks (primarily granodiorite and gneiss) to the west. Mean annual temperature declines and mean annual precipitation increases with elevation, from ~11° C/490 mm at the western edge of the Plains to -3.7° C/930 mm on Niwot Ridge near the range crest. The range contains regions of low relief with rolling topography, in which slopes rarely exceed 20° , as well as deeply incised glacial valleys and fluvial canyons lined by steep slopes (>25° ). Cosmogenic 10Be based erosion rates vary by a factor of ~5 within crystalline rock across the range. The lowest rates (5-10 mm/ka) are found on low relief summit tors in the alpine, where temperatures are low and precipitation is high. Slightly higher erosion rates (20-30 mm/ka) are found in low relief crystalline rock areas with montane forest cover. Taken together, these rates suggest that on low slopes, rock-weathering rates (which place a fundamental limit on erosion rates) are lower in cold alpine settings. Over the 40-150 ka averaging time of 10Be erosion rates, lower rates are found where periglacial/tundra conditions have prevailed, while moderate rates occur where conditions have varied from periglacial/tundra in the past to frigid regime/montane forest in the Holocene. Higher basin-averaged erosion rates of 40-60 mm/ka are reported for 'canyon edge' basins (Dethier et al., 2014, Geology), which are small, steep basins responding to fluvial bedrock incision that formed the canyons in the late Cenozoic. Are higher erosion rates in canyon-edge basins evidence that topographic slope affects weathering rates? We argue that it is more likely that these high erosion rates reflect faster weathering in areas with thinner soil cover. A recent major storm unleashed landslides and debris flows from ~10% of these canyon-edge basins. On average, the volume of material evacuated in these basins was equivalent to ~300 years of soil production by weathering at these rates, approximately the recurrence interval of the storm. The conceptual model that emerges is that agents that cut into rock (bedrock rivers, glaciers) set the pace for exhumation. Adjoining hillslopes erode at a pace set by weathering in the prevailing climate/vegetation regime, conditioned by the ability of sediment transport processes to limit soil thickness on the slopes.
Melloul, Emmanuel; Denys, Alban; Demartines, Nicolas
2015-09-01
During the last decade, the management of blunt hepatic injury has considerably changed. Three options are available as follows: nonoperative management (NOM), transarterial embolization (TAE), and surgery. We aimed to evaluate in a systematic review the current practice and outcomes in the management of Grade III to V blunt hepatic injury. The MEDLINE database was searched using PubMed to identify English-language citations published after 2000 using the key words blunt, hepatic injury, severe, and grade III to V in different combinations. Liver injury was graded according to the American Association for the Surgery of Trauma classification on computed tomography (CT). Primary outcome analyzed was success rate in intention to treat. Critical appraisal of the literature was performed using the validated National Institute for Health and Care Excellence "Quality Assessment for Case Series" system. Twelve articles were selected for critical appraisal (n = 4,946 patients). The median quality score of articles was 4 of 8 (range, 2-6). Overall, the median Injury Severity Score (ISS) at admission was 26 (range, 0.6-75). A median of 66% (range, 0-100%) of patients was managed with NOM, with a success rate of 94% (range, 86-100%). TAE was used in only 3% of cases (range, 0-72%) owing to contrast extravasation on CT with a success rate of 93% (range, 81-100%); however, 9% to 30% of patients required a laparotomy. Thirty-one percent (range, 17-100%) of patients were managed with surgery owing to hemodynamic instability in most cases, with 12% to 28% requiring secondary TAE to control recurrent hepatic bleeding. Mortality was 5% (range, 0-8%) after NOM and 51% (range, 30-68%) after surgery. NOM of Grade III to V blunt hepatic injury is the first treatment option to manage hemodynamically stable patients. TAE and surgery are considered in a highly selective group of patients with contrast extravasation on CT or shock at admission, respectively. Additional standardization of the reports is necessary to allow accurate comparisons of the various management strategies. Systematic review, level IV.
Goorens, Chul Ki; Geeurickx, Stijn; Wernaers, Pascal; Staelens, Barbara; Scheerlinck, Thierry; Goubau, Jean
2017-06-01
Specific treatment of the volar marginal rim fragment of distal radius fractures avoids occurance of volar radiocarpal dislocation. Although several fixation systems are available to capture this fragment, adequately maintaining internal fixation is difficult. We present our experience of the first 10 cases using the 2.4 mm variable angle LCP volar rim distal radius plate (Depuy Synthes®, West Chester, US), a low-profile volar rim-contouring plate designed for distal plate positioning and stable buttressing of the volar marginal fragment. Follow-up patient satisfaction, range of motion, grips strength, functional scoring with the QuickDASH and residual pain with a numeric rating scale were assessed. Radiological evaluation consisted in evaluating fracture consolidation, ulnar variance, volar angulation and maintenance of the volar rim fixation. The female to male ratio was 5:5 and the mean age was 52.2 (range, 17-80) years. The mean follow-up period was 11 (range, 5-19) months postoperatively. Patient satisfaction was high. The mean total flexion/extension range was 144° (range, 100-180°) compared to the contralateral uninjured side 160° (range, 95-180°). The mean total pronation/supination range was 153° (range, 140-180°) compared to the contralateral uninjured side 170° (range, 155-180°). Mean grip strength was 14 kg (range, 9-22), compared to the contralateral uninjured side 20 kg (range, 12-25 kg). Mean pre-injury level activity QuickDASH was 23 (range, 0-34.1), while post-recovery QuickDASH was 25 (range 0-43.2). Residual pain was 1.5 on the visual numerical pain rating scale. Radiological evaluation revealed in all cases fracture consolidation, satisfactory reconstruction of ulnar variance, volar angulation and volar rim. We encountered no flexor tendon complications, although plate removal was systematically performed after fracture consolidation. The 2.4 mm variable angle LCP volar rim distal radius plates is a valid treatment option for treating the volar marginal fragment in distal radius fractures.
Deng, Ang; Zhang, Hong-Qi; Tang, Ming-Xing; Liu, Shao-Hua; Wang, Yu-Xiang; Gao, Qi-Le
2017-01-01
OBJECTIVE The objective of this study was to evaluate the clinical efficacy of posterior-only surgical correction of dystrophic scoliosis in patients with neurofibromatosis Type 1 (NF1) using a multiple anchor point method (MAPM). METHODS From 2005 to 2014, 31 patients (mean age 13.5 years old, range 10-22 years old) suffering from dystrophic scoliosis associated with NF1 underwent posterior-only surgical correction using a MAPM. The apex of the deformity was thoracic (n = 25), thoracolumbar (n = 4), and lumbar (n = 2). The mean preoperative coronal Cobb angle was 69.1° (range 48.9°-91.4°). The mean Cobb angle on the side-bending radiograph of the convex side was 58.2° (range 40°-79.8°). The mean flexibility and apical vertebral rotation (AVR) were 15.6% (range 8.3%-28.2%) and 2.5° (range 2°-3°), respectively. The mean angle of sagittal kyphosis was 58.3° (range 34.1°-79.6°). RESULTS The mean follow-up period was 53 months (range 12-96 months). The mean postoperative coronal Cobb angle was 27.4° (range 16.3°-46.7°). Postoperatively, the mean AVR and angle of sagittal kyphosis were 1.2° (range 1°-2°) and 22.4° (range 4.2°-36.3°), respectively. All patients showed good correction of all indices postoperatively. The mean postoperative correction rate was 58.7% (range 46.3%-74.1%). At the final follow-up evaluation, the corrective loss rate of the Cobb angle was only 2.3%. Only 1 patient required revision surgery. No severe complications such as spinal cord, neural, or large vascular injury occurred during the operation. CONCLUSIONS Posterior-only surgical correction of dystrophic scoliosis in patients with NF1 using a MAPM could yield satisfactory clinical efficacy of correction and fusion.
NASA Astrophysics Data System (ADS)
Higashino, Satoru; Kobayashi, Shoei; Yamagami, Tamotsu
2007-06-01
High data transfer rate has been demanded for data storage devices along increasing the storage capacity. In order to increase the transfer rate, high-speed data processing techniques in read-channel devices are required. Generally, parallel architecture is utilized for the high-speed digital processing. We have developed a new architecture of Interpolated Timing Recovery (ITR) to achieve high-speed data transfer rate and wide capture-range in read-channel devices for the information storage channels. It facilitates the parallel implementation on large-scale-integration (LSI) devices.
Radio Wave Propagation over Salem
NASA Astrophysics Data System (ADS)
Jaiswal, R. S.; Uma, S.; Raj, M. V. A.
2007-07-01
In this paper study of rainfall has been carried out over Salem, a place in Southern India. Rainfall rate values have been recorded using a fast response rain gauge installed at Sona College of Technology. The derived rainfall rates have been used to estimate attenuation in the 10-100 GHz frequency range. Using the estimated co-polar attenuation cross polar discriminations (XPD) have been computed using ITU-R(2002) model in the 10-35 GHz range. The study shows that attenuation and cross polarization vary with frequency, elevation angle and rainfall rate. The study also depicts the cumulative distribution of rainfall rate, attenuation and XPD.
Dynamic strain aging in the high-temperature low-cycle fatigue of SA508 Cl. 3 forging steel
NASA Astrophysics Data System (ADS)
Lee, Byung Ho; Kim, In Sup
1995-10-01
The effect of dynamic strain aging on cyclic stress response and fatigue resistance of ASME SA508 Cl.3 forging steel for nuclear reactor pressure vessels has been evaluated in the temperature range of room temperature to 500°C. Total strain ranges and strain rates were varied from 0.7 to 2.0% and from 4 × 10 -4 to 1 × 10 -2 s -1, respectively. The cyclic stress response depended on the testing temperature, strain rate, and range. Generally, the initial cyclic hardening was immediately followed by cyclic softening at all strain rates. However, at 300°C, the operating temperature of nuclear reactor pressure vessels, the variation of cyclic stress amplitude showed the primary and secondary hardening stages dependent on the strain rate and strain range. Dynamic strain aging was manifested by enhanced cyclic hardening, distinguished secondary hardening, and negative strain rate sensitivity. A modified cell shutting model was described for the onset of the secondary hardening due to the dynamic strain aging and it was in good agreement with the experimental results. Fatigue life increased in strain rate at all testing temperatures. Specifically the fatigue life was longer at the dynamic strain aging temperature. Further, the dynamic strain aging was easy to initiate the crack, while crack propagation was retarded by crack branching and suppression of plastic zone, hence the dynamic strain aging caused the improvement of fatigue resistance.
NASA Astrophysics Data System (ADS)
Kuwahara, Akira; Matsui, Makoto; Yamagiwa, Yoshiki
2012-12-01
A vacuum ultraviolet absorption spectroscopy system for a wide measurement range of atomic number densities is developed. Dual-tube inductively coupled plasma was used as a light source. The probe beam profile was optimized for the target number density range by changing the mass flow rate of the inner and outer tubes. This system was verified using cold xenon gas. As a result, the measurement number density range was extended from the conventional two orders to five orders of magnitude.
AUTOMOTIVE EMISSIONS OF ETHYLENE DIBROMIDE
Ethylene dibromide, a suspected carcinogen, and ethylene dichloride are commonly used in leaded gasoline as scavengers. Ethylene dibromide emission rates were determined from seven automobiles which had a wide range of control devices, ranging from totally uncontrolled to evapora...
Assessment of range planting as a conservation practice
USDA-ARS?s Scientific Manuscript database
Natural Resource Conservation Service (NRCS) Range Planting - Conservation Practice Standards provide guidelines for making decisions about seedbed preparation, planting methods, plant materials selection, seeding rate, seeding depth, timing of seeding, post-planting management, and weed-control. ...
Self-Calibrating Respiratory-Flowmeter Combination
NASA Technical Reports Server (NTRS)
Westenskow, Dwayne R.; Orr, Joseph A.
1990-01-01
Dual flowmeters ensure accuracy over full range of human respiratory flow rates. System for measurement of respiratory flow employs two flowmeters; one compensates for deficiencies of other. Combination yields easily calibrated system accurate over wide range of gas flow.
NASA Astrophysics Data System (ADS)
Ya’acob, A. M.; Razali, D. A.; Anwar, U. A.; Radhi, A. H.; Ishak, A. A.; Minhat, M.; Aris, K. D. Mohd; Johari, M. K.; Casey, T.
2018-05-01
This project involves discovering how the permeability effect inside a close compartment in processing. After the appropriate pressure range was found, the close compartment was designed by studying the relationship between pressure output and the flow rate. A variety of pressure ranges have been used in this test to determine the effective pressure range that can be applied to the manufacturing process. Based on the results, the suitable pressure ranges were found between 55 psi to 75 psi. These pressures have been chosen based on the area covered on the product surfaces and time taken to penetrate the proposed area. The relationship between pressure and flow rate have been found to be directly proportional until 75 psi only. In conclusion, 70 psi for the proposed design of close compartment mould is suitable to be used to fulfill the required area of 120 mm square within 90 seconds.
Furtado, Mariana Malzoni; Kashivakura, Cynthia Kayo; Ferro, Claudia; de Almeida, Jácomo Anah Tereza; Silveira, Leandro; Astete, Samuel
2006-03-01
A tiletamine hydrochloride-zolazepam hydrochloride combination was used successfully to immobilize 27 free-ranging maned wolves (Chrysocyon brachyurus) at a mean dose of 2.77+/-0.56 (mean+/-SD) mg/kg. The induction time ranged from 3-15 min. Animals remained immobilized for periods of 48.56 +/-12.65 min. Compulsive licking, excessive salivation, muscle twitching, muscle tremors, tachypnea, and bradycardia were observed associated with the induction of the anesthesia in 13 of 27 maned wolves. Muscle twitching, pedal withdrawal reflex, muscle tremors, and ataxia were observed during recovery in three (11%) maned wolves. There were no significant differences in heart rates (P = 0.44), respiratory rates (P = 0.82), and rectal temperatures (P = 0.54) recorded at 5, 15, and 25 min after induction at these dosages. The tiletamine hydrochloride-zolazepam hydrochloride combination was shown to be an effective and safe immobilizing agent for free-ranging maned wolves.
Long-range ordered vorticity patterns in living tissue induced by cell division
NASA Astrophysics Data System (ADS)
Rossen, Ninna S.; Tarp, Jens M.; Mathiesen, Joachim; Jensen, Mogens H.; Oddershede, Lene B.
2014-12-01
In healthy blood vessels with a laminar blood flow, the endothelial cell division rate is low, only sufficient to replace apoptotic cells. The division rate significantly increases during embryonic development and under halted or turbulent flow. Cells in barrier tissue are connected and their motility is highly correlated. Here we investigate the long-range dynamics induced by cell division in an endothelial monolayer under non-flow conditions, mimicking the conditions during vessel formation or around blood clots. Cell divisions induce long-range, well-ordered vortex patterns extending several cell diameters away from the division site, in spite of the system’s low Reynolds number. Our experimental results are reproduced by a hydrodynamic continuum model simulating division as a local pressure increase corresponding to a local tension decrease. Such long-range physical communication may be crucial for embryonic development and for healing tissue, for instance around blood clots.
Underreporting of musculoskeletal disorders in 10 regions in France in 2009.
Rivière, Stéphanie; Penven, Emmanuelle; Cadéac-Birman, Hélène; Roquelaure, Yves; Valenty, Madeleine
2014-10-01
Underreporting of occupational diseases (OD) has been quantified, in particular in the United States, but little information is available in other countries. The aim of this study was to evaluate underreporting of musculoskeletal disorders (MSD) in France in 2009. We calculated an indicator that approximated the underreporting rate of MSD in 10 regions of France. Two databases were used: data on OD compensated by insurance funding and data from the surveillance program for uncompensated work-related diseases. Analyses were performed for carpal tunnel syndrome (CTS) and elbow, shoulder, and lumbar spine MSD. The underreporting rate was estimated at 59% (range 52-64%) for CTS, 73% (range 67-79%) for elbow MSD, 69% (range 63-74%) for shoulder MSD, and 63% (range 50-76%) for lumbar spine MSD. This study revealed that MSD are substantially underreported in France, as in the United States, despite the differences in workers' compensation systems. © 2014 Wiley Periodicals, Inc.
Chen, Gang; Xu, Zhengyuan; Ding, Haipeng; Sadler, Brian
2009-03-02
We consider outdoor non-line-of-sight deep ultraviolet (UV) solar blind communications at ranges up to 100 m, with different transmitter and receiver geometries. We propose an empirical channel path loss model, and fit the model based on extensive measurements. We observe range-dependent power decay with a power exponent that varies from 0.4 to 2.4 with varying geometry. We compare with the single scattering model, and show that the single scattering assumption leads to a model that is not accurate for small apex angles. Our model is then used to study fundamental communication system performance trade-offs among transmitted optical power, range, link geometry, data rate, and bit error rate. Both weak and strong solar background radiation scenarios are considered to bound detection performance. These results provide guidelines to system design.
Experimental demonstration of multiuser communication in deep water using time reversal.
Shimura, T; Ochi, H; Song, H C
2013-10-01
Multiuser communication is demonstrated using experimental data (450-550 Hz) collected in deep water, south of Japan. The multiple users are spatially distributed either in depth or range while a 114-m long, 20-element vertical array (i.e., base station) is deployed to around the sound channel axis (~1000 m). First, signals received separately from ranges of 150 km and 180 km at various depths are combined asynchronously to generate multiuser communication sequences for subsequent processing, achieving an aggregate data rate of 300 bits/s for up to three users. Adaptive time reversal is employed to separate collided packets at the base station, followed by a single channel decision feedback equalizer. Then it is demonstrated that two users separated by 3 km in range at ~1000 m depth can transmit information simultaneously to the base station at ~500 km range with an aggregate data rate of 200 bits/s.
NASA Astrophysics Data System (ADS)
Chakrabarti, Surajit
2015-11-01
We have performed an experiment in which we have determined the viscosity of air using the Hagen-Poiseuille equation in the proper range of the Reynolds number (Re). The experiment is novel and simple which students even at high school level can perform with minimal equipment.The experiment brings out the fact that determination of viscosity of a fluid is possible only when its Reynolds number is sufficiently small. At very large Reynolds number, the gas behaves more like an inviscid fluid and its flow rate satisfies Bernoulli’s equation. In the intermediate range of the Reynolds number, the flow rate satisfies neither the Hagen-Poiseuille equation nor the Bernoulli equation. A wide range of Reynolds numbers from 40 to about 5000 has been studied. In the case of air, this large range has not shown any sign of turbulence.
Climatic and Tectonic Controls on Topography in the Northern Basin and Range
NASA Astrophysics Data System (ADS)
Foster, D.; Brocklehurst, S. H.; Gawthorpe, R. L.
2006-12-01
This study takes advantage of the relatively simple tectonics of the normal fault-bounded Lost River and Lemhi Ranges and the Beaverhead Mountains, eastern Idaho, USA, to assess the roles of climate, erosion, and tectonics in topographic evolution through a combination of digital topographic analyses and field observations. These ranges transect the southern limit of Quaternary glaciation, and drainage basins record a range of glacial extents and histories, allowing for comparisons between climatic and tectonic controls. At a catchment scale, topography is controlled by both the degree of glaciation, and the response of the drainage system to range-front faulting. The range-bounding normal faults are segmented along-strike, and fault uplift rates vary systematically, being greatest at the fault centres. Here catchments predominantly drain normal to the range-front fault, although the trend of some catchments is influenced by pre-existing tectonic fabrics related to Cretaceous (northeast-southwest trending) and early Miocene (northwest-southeast trending) extension. For catchments that drain through fault segment boundaries, one of two general morphologies occurs. Either large drainage basins form, capturing drainage area from neighbouring basins, or, when fault segment boundaries are en echelon, a series of small drainage basins may form as catchments as the inboard- and outboard- footwalls interact and respond to fault linkage. Quaternary glaciation affected all but the southern portions of each of the ranges, most extensively at the north-eastern range flank. Increased extent of glaciation within a catchment results in wider valley floors, steeper valley walls, and greater relief at elevations close to the ELA. Cirque formation occurs preferentially on the north-eastern range flank, where glaciers are sheltered from both solar radiation and snow re-distribution by the prevailing winds. Snow accumulation is promoted in this setting by the increased influx of wind-blown snow from the western side of the range crest, and large moraines extend beyond the eastern range front. For portions of the ranges affected by glaciation, range mean heights decrease along-strike by 1-2m per km to the north-west, similar to the rate of decrease in ELA and in the trend of cirque floor elevations. This suggests that a glacial "buzzsaw" effect controls the range mean heights.
Plasma concentrations of midazolam during continuous subcutaneous administration in palliative care.
Bleasel, M D; Peterson, G M; Dunne, P F
1994-01-01
We have investigated the steady-state plasma concentrations of midazolam during continuous subcutaneous administration in palliative care. Using a sensitive gas chromatography with electron capture detector assay, plasma concentrations of midazolam were measured in 11 patients (median age 68 years; range 47-82 years; six females) receiving the drug by continuous subcutaneous infusion (median rate 20 mg/day; range 10-60 mg/day). While not significant, the infusion rate tended to decrease with increasing age of the patient (Spearman's p = -0.51; p = 0.11). The steady-state plasma concentration range was 10-147 ng/ml, with a median of 30 ng/ml. Infusion rates and plasma concentrations of midazolam were correlated (Spearman's p = 0.71; p < 0.05). No other significant relationships were found between plasma concentrations and the variables of age, sex and liver function.
A micromixer with consistent mixing performance for a wide range of flow rates.
Goovaerts, Robert; Van Assche, Tom; Sonck, Marc; Denayer, Joeri; Desmet, Gert
2015-02-01
A micromixer with consistent mixing performance for a wide range of flow rates is presented. The mixer makes use of internally moving elements, i.e. steel balls that are located in dedicated mixing chambers. Movement is induced by a rotating magnetic field. To get better insight in differences between active and passive mixing, we studied a mixer that can operate in both regimes. A mixing performance study for a range of flow rates along with pressure drop data is presented. The response of the moving elements in regard to the magnetic field is shown experimentally and shows the limitations of earlier modeling studies. Lastly, the estimated power input on the fluids was calculated and allows for a comparison with more well-known convective-type mixers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Qin, Heng; Zuo, Yong; Zhang, Dong; Li, Yinghui; Wu, Jian
2017-03-06
Through slight modification on typical photon multiplier tube (PMT) receiver output statistics, a generalized received response model considering both scattered propagation and random detection is presented to investigate the impact of inter-symbol interference (ISI) on link data rate of short-range non-line-of-sight (NLOS) ultraviolet communication. Good agreement with the experimental results by numerical simulation is shown. Based on the received response characteristics, a heuristic check matrix construction algorithm of low-density-parity-check (LDPC) code is further proposed to approach the data rate bound derived in a delayed sampling (DS) binary pulse position modulation (PPM) system. Compared to conventional LDPC coding methods, better bit error ratio (BER) below 1E-05 is achieved for short-range NLOS UVC systems operating at data rate of 2Mbps.
Amino acid geochemistry of fossil bones from the Rancho La Brea asphalt deposit, California
McMenamin, M.A.S.; Blunt, D.J.; Kvenvolden, K.A.; Miller, S.E.; Marcus, L.F.; Pardi, R.R.
1982-01-01
Low aspartic acid d:l ratios and modern collagenlike concentration values indicate that amino acids in bones from the Rancho La Brea asphalt deposit, Los Angeles, California are better preserved than amino acids in bones of equivalent age that have not been preserved in asphalt. Amino acids were recovered from 10 Rancho La Brea bone samples which range in age from less than 200 to greater than 36,000 yr. The calibrated rates of aspartic acid racemization range from 2.1 to 5.0 ?? 10-6yr-1. Although this wide range of rate constants decreases the level of confidence for age estimates, use of the larger rate constant of 5.0 ?? 10-6yr-1 provides minimum age estimates which fit the known stratigraphic and chronologic records of the Rancho La Brea deposits. ?? 1982.
A parallel implementation of a multisensor feature-based range-estimation method
NASA Technical Reports Server (NTRS)
Suorsa, Raymond E.; Sridhar, Banavar
1993-01-01
There are many proposed vision based methods to perform obstacle detection and avoidance for autonomous or semi-autonomous vehicles. All methods, however, will require very high processing rates to achieve real time performance. A system capable of supporting autonomous helicopter navigation will need to extract obstacle information from imagery at rates varying from ten frames per second to thirty or more frames per second depending on the vehicle speed. Such a system will need to sustain billions of operations per second. To reach such high processing rates using current technology, a parallel implementation of the obstacle detection/ranging method is required. This paper describes an efficient and flexible parallel implementation of a multisensor feature-based range-estimation algorithm, targeted for helicopter flight, realized on both a distributed-memory and shared-memory parallel computer.
Variation in spring harvest rates of male wild turkeys in New York, Ohio, and Pennsylvania
Diefenbach, Duane R.; Casalena, Mary Jo; Schiavone, Michael V.; Reynolds, Michael; Eriksen, Robert; Vreeland, Wendy C.; Swift, Bryan L.; Boyd, Robert C.
2012-01-01
Spring harvest rates of male wild turkeys (Meleagris gallapavo) influence the number and proportion of adult males in the population and turkey population models have treated harvest as additive to other sources of mortality. Therefore, hunting regulations and their effect on spring harvest rates have direct implications for hunter satisfaction. We used tag recovery models to estimate survival rates, investigate spatial, temporal, and demographic variability in harvest rates, and assess how harvest rates may be related to management strategies and landscape characteristics. We banded 3,266 male wild turkeys throughout New York, Ohio, and Pennsylvania during 2006–2009. We found little evidence that harvest rates varied by year or management zone. The proportion of the landscape that was forested within 6.5 km of the capture location was negatively related to harvest rates; however, even though the proportion forested ranged from 0.008 to 0.96 across our study area, this corresponded to differences in harvest rates of only 2–5%. Annual survival was approximately twice as high for juveniles as adults . In turn, spring harvest rates for adult turkeys were greater for adults than juveniles . We estimated the population of male turkeys in New York and Pennsylvania ranged from 104,000 to 132,000 in all years and ranged from 63,000 to 75,000 in Ohio. Because of greater harvest rates for adult males, the proportion of adult males in the population was less than in the harvest and ranged from 0.40 to 0.81 among all states and years. The high harvest rates observed for adults may be offset by greater recruitment of juveniles into the adult age class the following year such that these states can sustain high harvest rates yet still maintain a relative high proportion of adult males in the harvest and population.
NASA Astrophysics Data System (ADS)
Tan, A.; Shahrill, M.; Daud, S.; Leung, E.
2018-03-01
The purpose of this paper is to show that short-ranged dependence prevailed for Singapore-Malaysia exchange. Although, it is perceived that there is some evidence of long-ranged dependence [1,2], it is still unclear whether Singapore-Malaysia exchange indeed exhibits long-ranged dependence. For this paper, we focus on the currency rate for a sixteen-year period ranging from September 2002 to September 2017. We estimate the Hurst parameter using the famous rescaled R/S statistics technique. From our analysis, we showed that the Hurst parameter is approximately 0.5 which indicates short-ranged dependence. This short memory property is further validated by performing a one-tailed z-test whose alternative hypothesis is that the Hurst parameter is not 0.5 at 1% significance level. We conclude that the alternative hypothesis is rejected. The existence of short memory proves that the behaviour of the exchange rate is unpredictable, supporting the efficient market hypothesis, which states that not only is price movement completely random but also tomorrow’s prices are predicted by all the information in today’s prices.
Zhao, Anbang; Zeng, Caigao; Hui, Juan; Ma, Lin; Bi, Xuejie
2017-01-01
This paper proposes a composite channel virtual time reversal mirror (CCVTRM) for vertical sensor array (VSA) processing and applies it to long-range underwater acoustic (UWA) communication in shallow water. Because of weak signal-to-noise ratio (SNR), it is unable to accurately estimate the channel impulse response of each sensor of the VSA, thus the traditional passive time reversal mirror (PTRM) cannot perform well in long-range UWA communication in shallow water. However, CCVTRM only needs to estimate the composite channel of the VSA to accomplish time reversal mirror (TRM), which can effectively mitigate the inter-symbol interference (ISI) and reduce the bit error rate (BER). In addition, the calculation of CCVTRM is simpler than traditional PTRM. An UWA communication experiment using a VSA of 12 sensors was conducted in the South China Sea. The experiment achieves a very low BER communication at communication rate of 66.7 bit/s over an 80 km range. The results of the sea trial demonstrate that CCVTRM is feasible and can be applied to long-range UWA communication in shallow water. PMID:28653976
Effect of Control Mode and Test Rate on the Measured Fracture Toughness of Advanced Ceramics
NASA Technical Reports Server (NTRS)
Hausmann, Bronson D.; Salem, Jonathan A.
2018-01-01
The effects of control mode and test rate on the measured fracture toughness of ceramics were evaluated by using chevron-notched flexure specimens in accordance with ASTM C1421. The use of stroke control gave consistent results with about 2% (statistically insignificant) variation in measured fracture toughness for a very wide range of rates (0.005 to 0.5 mm/min). Use of strain or crack mouth opening displacement (CMOD) control gave approx. 5% (statistically significant) variation over a very wide range of rates (1 to 80 µm/m/s), with the measurements being a function of rate. However, the rate effect was eliminated by use of dry nitrogen, implying a stress corrosion effect rather than a stability effect. With the use of a nitrogen environment during strain controlled tests, fracture toughness values were within about 1% over a wide range of rates (1 to 80 micons/m/s). CMOD or strain control did allow stable crack extension well past maximum force, and thus is preferred for energy calculations. The effort is being used to confirm recommendations in ASTM Test Method C1421 on fracture toughness measurement.
Prospective randomized study of chevron osteotomy versus Mitchell's osteotomy in hallux valgus.
Buciuto, Robert
2014-12-01
We conducted a prospective randomized trial to compare the most popular osteotomy types of operative treatment of hallux valgus (HV) used in Norway, Mitchell's osteotomy (MO) and chevron osteotomy (CO). One hundred twenty adult female patients were prospectively randomized to treatment with either MO or CO. All operative procedures were performed with ankle block and with tourniquet applied. None of the patients received any antibiotic or antithrombotic prophylaxis. The follow-up period was 3 years. Clinical results were rated according to the American Orthopaedic Foot and Ankle Society (AOFAS) Clinical Rating System (CRS). HV in the MO group was reduced from 30 (range, 20 to 44) to 15 (range, 8 to 24) degrees and IM angle from 11 (range, 6 to 14) to 7 (range, 4 to 11) degrees. HV in the CO group was reduced from 31 (range, 22 to 42) to 16 (range, 6 to 24) degrees and IM angle from 14 (range, 8 to 20) to 6 (range, 2 to 10) degrees. Transfer metatarsalgia occurred in 36 (60%) patients and hammertoe in 6 (10%) patients in the MO group. In the CO group, metatarsalgia occurred in 5 patients. The median loss of postoperative HV correction was 4 (range, 2 to 10) degrees in mild deformity and 6 (6 to 10) degrees in moderate deformity. Patients treated with CO had significantly better results for AOFAS CRS, number of postoperative complications, patient satisfaction, and length of sick leave for the employed patients. Based on our results, we consider that in female patients CO should be regarded as the first-line procedure for treatment of mild and moderate HV. Level I, prospective randomized study. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Angelica, P. E.; Griffin, K. L.
2016-12-01
The Hudson Valley Region of New York State, USA is known for a convergence of tree species within the eastern deciduous forest that are near the margin of their geographical range limits. This convergence of primarily southern ranged species with primarily northern ranged species provides the back drop to our study of respiratory activity of 16 forest tree species - 10 broadleaf and 6 coniferous. We found that broadleaved species at the southern edge of their range have significantly higher rates of respiration than trees that are in the center or northern edge of their range, which is contrasting to the lower respiration rates found in northern ranged conifers when compared to their central ranged counterparts . Using a simple closed system to estimate the Respiratory Quotient (RQ - CO2 uptake vs. O2 released) for 10 broadleaved species, we found that northern broadleaved species were more likely to be incorporating some proteins and/or fats as respiratory substrates (RQ<1), compared to central or southern species (RQ 1). All 16 species had similar temperature response of respiration, regardless of the species range or growth type (broadleaved vs. coniferous). In addition, broadleaved species showed an increasing RQ with increasing leaf temperature (from <1 at 15 °C to >1 at 35 °C) indicating the temperature dependence of respiratory substrates that transitions from proteins and fats to carbohydrates and eventually some organic acids as temperatures increase. Overall, this work suggests the fate of fixed carbon in an eastern deciduous forest is controlled by a variety of factors including genetic and environmental variables. As a result, the impact of climate change is likely to change the composition and biogeochemistry of this widespread forest biome.
Shoreline Erosion in the Albemarle-Pamlico Estuarine System, Northeastern North Carolina
NASA Astrophysics Data System (ADS)
Murphy, M. A.; Riggs, S. R.
2002-12-01
Computer analysis of aerial photographic series demonstrates that the estuarine shorelines within the North Carolina Albemarle-Pamlico coastal system are eroding at 2-3 times greater rates than previous studies reported. Specific rates and amounts of shoreline recession vary tremendously depending upon local variables including: 1) shoreline type, geometry, and composition; 2) geographic location, size, and shape of associated estuary; 3) frequency, intensity, and fetch of storms; 4) type and abundance of associated vegetation; and locally 5) boat wakes. Organic or wetland shorelines (marsh and swamp forest) comprise approximately 62% of the estuarine margins in NE NC, whereas sediment banks (low, high, and bluff) constitute about 38%. The goals of this study were to determine the rates of recession for different shoreline types and the role of local variables in the erosion process. Shorelines were mapped using high precision GPS mapping techniques, digital orthographic quarter quadrangles, and other georeferenced aerial photographs from the early 1950's to 2001. Shoreline change was then calculated for 20 estuarine study sites. Field mapping of each site provided data on shoreline characteristics and erosional processes. Data synthesis suggests mean annual shoreline erosion rates are significantly different for shoreline types as follows: 1) marshes = 7.4 ft/yr (range 2.7-17.0 ft/yr), low sediment banks = 5.0 ft/yr (range 1.0-12.0 ft/yr), bluff sediment banks = 5.0 ft/yr (range = 3.9-6.0 ft/yr), swamp forests = 3.0 ft/yr (range = 1.7-4.0 ft/yr), high sediment banks = 2.8 ft/yr (range = 2.7-2.9 ft/yr). Modified shorelines continue to erode, however at lower mean annual rates that range from 0.9-2.7 ft/yr. Locally, specific marsh shorelines have eroded at rates up to 100 ft/yr during particularly stormy periods. Thus, about 1166 acres of land are lost each year along the 1593 miles of mapped estuarine shoreline in NE NC. If these erosion rates are representative of all 3,000 miles of NE NC's estuarine shorelines, if sea level continues to rise, and if the storm pattern persists at present levels, NC will experience significant loss of both wetlands and uplands at the estuarine water-land interface.
Fey, D P
2015-01-01
The effect of sampling with bongo (0·6 m diameter frame with 500 µm mesh) and Methot Isaac Kidd (MIK) (2 m diameter frame with 2 mm mesh finished with 500 µm codend) nets on standard length (LS ) range and growth rate differences was tested for larval Sprattus sprattus (n = 906, LS range: 7·0-34·5 mm) collected during four cruises in the summer months of 2006, 2007, 2009 and 2010 in the southern Baltic Sea. Although the minimum size of larvae collected with the bongo and MIK nets was similar in each cruise (from c. 7 to 9 mm), the MIK nets permitted collecting larger specimens (up to c. 34 mm) than the bongo nets did (up to c. 27 mm). The growth rates of larvae collected with the bongo and MIK nets (specimens of the same size range were compared for three cruises) were not statistically different (mean = 0·55 mm day(-1) , n = 788, LS range: 7·0-27·4 mm), which means the material collected with these two nets can be combined and growth rate results between them were compared. © 2014 The Fisheries Society of the British Isles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sturrock, P. A.; Fischbach, E.; Jenkins, J.
2014-10-10
We present the results of an analysis of measurements of the beta-decay rates of Ag 108, Ba 133, Eu 152, Eu 154, Kr 85, Ra 226, and Sr 90 acquired at the Physikalisch-Technische Bundesanstalt from 1990 through 1995. Although the decay rates vary over a range of 165 to 1 and the measured detector current varies over a range of 19 to 1, the detrended and normalized count rate measurements exhibit a sinusoidal annual variation with amplitude in the small range 0.068%-0.088% (mean 0.081%, standard deviation 0.0072%, a rejection of the zero-amplitude hypothesis) and phase-of-maximum in the small range 0.062-0.083more » (January 23 to January 30). In comparing these results with those of other related experiments that yield different results, it may be significant that this experiment, at a standards laboratory, seems to be unique in using a 4π detector. These results are compatible with a solar influence, and do not appear to be compatible with an experimental or environmental influence. It is possible that Ba 133 measurements are also subject to a non-solar (possibly cosmic) influence.« less
NASA Astrophysics Data System (ADS)
Narang, Saurabh; Kumar, Deepak; Sharma, Dinesh Kumar; Kumar, Ajay
2018-02-01
Over the last few decades, the study of radioactive radon gas has gained huge momentum due to its possible role in health related hazards. In the present work, pin-hole twin chamber single entrance dosimeters have been used for track measurements of radon and thoron. The annual average radon concentration varies from 50.3 to 204 Bq/m3 at all locations. Almost all the values are below the safe range provided by ICRP. Radon concentration is found to be higher in winter as compared to other seasons. Variation of radon with quality of dwellings is also discussed. The values of annual effective dose due to radon and thoron are also well within the range provided by ICRP and WHO. Radon and thoron exhalation rates are measured using SMART RnDuo monitor. The radon mass exhalation rates ranged from 11 to 71 mBq/kg/h while the thoron surface values ranged from 36 to 2048 Bq/m2/h. All the values are on the lower side. A weak correlation is found between radon and thoron concentrations and their exhalation rates. When compared with the values of other parts of northern India, the values of present investigation are on higher side.
Soliton microcomb range measurement
NASA Astrophysics Data System (ADS)
Suh, Myoung-Gyun; Vahala, Kerry J.
2018-02-01
Laser-based range measurement systems are important in many application areas, including autonomous vehicles, robotics, manufacturing, formation flying of satellites, and basic science. Coherent laser ranging systems using dual-frequency combs provide an unprecedented combination of long range, high precision, and fast update rate. We report dual-comb distance measurement using chip-based soliton microcombs. A single pump laser was used to generate dual-frequency combs within a single microresonator as counterpropagating solitons. We demonstrated time-of-flight measurement with 200-nanometer precision at an averaging time of 500 milliseconds within a range ambiguity of 16 millimeters. Measurements at distances up to 25 meters with much lower precision were also performed. Our chip-based source is an important step toward miniature dual-comb laser ranging systems that are suitable for photonic integration.
Cooling rates of group IVA iron meteorites
NASA Technical Reports Server (NTRS)
Willis, J.; Wasson, J. T.
1978-01-01
Cooling rates of six group IVA iron meteorites were estimated by a taenite central Ni concentration-taenite half-width method. Calculated cooling rates range from 13 to 25 C/Myr, with an average of 20 C/Myr. No correlation between cooling rate and bulk Ni content is observed, and the data appear to be consistent with a uniform cooling rate as expected from an igneous core origin. This result differs from previous studies reporting a wide range in cooling rates that were strongly correlated with bulk Ni content. The differences result mainly from differences in the phase diagram and the selected diffusion coefficients. Cooling rates inferred from taenite Ni concentrations at the interface with kamacite are consistent with those based on taenite central Ni content.
NASA Astrophysics Data System (ADS)
Iorio, Lorenzo
2018-05-01
We analytically calculate the time series for the perturbations Δ ρ \\left(t\\right), Δ \\dot{ρ }\\left(t\\right) induced by a general disturbing acceleration A on the mutual range ρ and range-rate \\dot{ρ } of two test particles A, B orbiting the same spinning body. We apply it to the general relativistic Lense-Thirring effect, due to the primary's spin S, and the classical perturbation arising from its quadrupole mass moment J2 for arbitrary orbital geometries and orientation of the source's symmetry axis {\\hat{S}}. The Earth-Mercury range and range-rate are nominally affected by the Sun's gravitomagnetic field to the 10 m, 10-3 cm s-1 level, respectively, during the extended phase (2026-2028) of the forthcoming BepiColombo mission to Mercury whose expected tracking accuracy is of the order of ≃0.1 m, 2 × 10-4 cm s-1. The competing signatures due to the solar quadrupole J_2^{\\odot }, if modelled at the σ _{J_2^{\\odot }}˜eq 10^{-9} level of the latest planetary ephemerides INPOP17a, are nearly 10 times smaller than the relativistic gravitomagnetic effects. The position and velocity vectors \\boldsymbol {r}, \\boldsymbol {v} of Mercury and Earth are changed by the solar Lense-Thirring effect by about 10 m, 1.5 m and 10-3 cm s-1, 10-5 cm s-1, respectively, over 2 yr; neglecting such shifts may have an impact on long-term integrations of the inner Solar system dynamics over ˜Gyr time-scales.
Dinh, Khuong Van; Janssens, Lizanne; Therry, Lieven; Bervoets, Lieven; Bonte, Dries; Stoks, Robby
2016-11-01
How exposure to contaminants may interfere with the widespread poleward range expansions under global warming is largely unknown. Pesticide exposure may negatively affect traits shaping the speed of range expansion, including traits related to population growth rate and dispersal-related traits. Moreover, rapid evolution of growth rates during poleward range expansions may come at a cost of a reduced investment in detoxification and repair thereby increasing the vulnerability to contaminants at expanding range fronts. We tested effects of a sublethal concentration of the widespread pesticide chlorpyrifos on traits related to range expansion in replicated edge and core populations of the poleward moving damselfly Coenagrion scitulum reared at low and high food levels in a common garden experiment. Food limitation in the larval stage had strong negative effects both in the larval stage and across metamorphosis in the adult stage. Exposure to chlorpyrifos during the larval stage did not affect larval traits but caused delayed effects across metamorphosis by increasing the incidence of wing malformations during metamorphosis and by reducing a key component of the adult immune response. There was some support for an evolutionary trade-off scenario as the faster growing edge larvae suffered a higher mortality during metamorphosis. Instead, there was no clear support for the faster growing edge larvae being more vulnerable to chlorpyrifos. Our data indicate that sublethal delayed effects of pesticide exposure, partly in association with the rapid evolution of faster growth rates, may slow down range expansions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Satellite tracking and Earth dynamics research programs
NASA Technical Reports Server (NTRS)
Pearlman, M. R.
1984-01-01
Following an upgrading program, ranging performance capabilities of a satellite-tracking pulsed laser system were assessed in terms of range accuracy, range noise, data yield, and reliability. With a shorter laser pulse duration (2.5 to 3.0 NSEC) and a new analog pulse processing system, the systematic range errors were reduced to 3 to 5 cm and range noise was reduced to 5 to 16 cm and range noise was reduced to 5 to 15 cm on Starlette and BE-C, and 10 to 18 cm on LAGEOS. Maximum pulse repetition rate was increased to 30 pulses per minute and significant improvement was made in signal to noise ratio by installing a 3 A interference filter and by reducing the range gate window to 200 to 400 nsec. The solution to a problem involving leakage of a fraction of the laser oscillator pulse through the pulse chopper was outlined.
Moving target parameter estimation of SAR after two looks cancellation
NASA Astrophysics Data System (ADS)
Gan, Rongbing; Wang, Jianguo; Gao, Xiang
2005-11-01
Moving target detection of synthetic aperture radar (SAR) by two looks cancellation is studied. First, two looks are got by the first and second half of the synthetic aperture. After two looks cancellation, the moving targets are reserved and stationary targets are removed. After that, a Constant False Alarm Rate (CFAR) detector detects moving targets. The ground range velocity and cross-range velocity of moving target can be got by the position shift between the two looks. We developed a method to estimate the cross-range shift due to slant range moving. we estimate cross-range shift by Doppler frequency center. Wigner-Ville Distribution (WVD) is used to estimate the Doppler frequency center (DFC). Because the range position and cross range before correction is known, estimation of DFC is much easier and efficient. Finally experiments results show that our algorithms have good performance. With the algorithms we can estimate the moving target parameter accurately.
NASA Technical Reports Server (NTRS)
Mcdonald, M. W.
1982-01-01
A frequency modulated continuous wave radar system was developed. The system operates in the 35 gigahertz frequency range and provides millimeter accuracy range and range rate measurements. This level of range resolution allows soft docking for the proposed teleoperator maneuvering system (TMS) or other autonomous or robotic space vehicles. Sources of error in the operation of the system which tend to limit its range resolution capabilities are identified. Alternative signal processing techniques are explored with emphasis on determination of the effects of inserting various signal filtering circuits in the system. The identification and elimination of an extraneous low frequency signal component created as a result of zero range immediate reflection of radar energy from the surface of the antenna dish back into the mixer of the system is described.
Structural properties of medium-range order in CuNiZr alloy
NASA Astrophysics Data System (ADS)
Gao, Tinghong; Hu, Xuechen; Xie, Quan; Li, Yidan; Ren, Lei
2017-10-01
The evolution characteristics of icosahedral clusters during the rapid solidification of Cu50Ni10Zr40 alloy at cooling rate of 1011 K s-1 are investigated based on molecular dynamics simulations. The structural properties of the short-range order and medium-range order of Cu50Ni10Zr40 alloy are analyzed by several structural characterization methods. The results reveal that the icosahedral clusters are the dominant short-range order structure, and that they assemble themselves into medium-range order by interpenetrating connections. The different morphologies of medium-range order are found in the system and include chain, triangle, tetrahedral, and their combination structures. The tetrahedral morphologies of medium-range order have excellent structural stability with decreasing temperature. The Zr atoms are favorable to form longer chains, while the Cu atoms are favorable to form shorter chains in the system. Those chains interlocked with each other to improve the structural stability.
Southern Appalachian hillslope erosion rates measured by soil and detrital radiocarbon in hollows
Hales, T.C.; Scharer, K.M.; Wooten, R.M.
2012-01-01
Understanding the dynamics of sediment generation and transport on hillslopes provides important constraints on the rate of sediment output from orogenic systems. Hillslope sediment fluxes are recorded by organic material found in the deposits infilling unchanneled convergent topographic features called hollows. This study describes the first hollow infilling rates measured in the southern Appalachian Mountains. Infilling rates (and bedrock erosion rates) were calculated from the vertical distribution of radiocarbon ages at two sites in the Coweeta drainage basin, western North Carolina. At each site we dated paired charcoal and silt soil organic matter samples from five different horizons. Paired radiocarbon samples were used to bracket the age of the soil material in order to capture the range of complex soil forming processes and deposition within the hollows. These dates constrain hillslope erosion rates of between 0.051 and 0.111mmyr-1. These rates are up to 4 times higher than spatially-averaged rates for the Southern Appalachian Mountains making creep processes one of the most efficient erosional mechanisms in this mountain range. Our hillslope erosion rates are consistent with those of forested mountain ranges in the western United States, suggesting that the mechanisms (dominantly tree throw) driving creep erosion in both the western United States and the Southern Appalachian Mountains are equally effective. ?? 2011 Elsevier B.V.
Improved pulse laser ranging algorithm based on high speed sampling
NASA Astrophysics Data System (ADS)
Gao, Xuan-yi; Qian, Rui-hai; Zhang, Yan-mei; Li, Huan; Guo, Hai-chao; He, Shi-jie; Guo, Xiao-kang
2016-10-01
Narrow pulse laser ranging achieves long-range target detection using laser pulse with low divergent beams. Pulse laser ranging is widely used in military, industrial, civil, engineering and transportation field. In this paper, an improved narrow pulse laser ranging algorithm is studied based on the high speed sampling. Firstly, theoretical simulation models have been built and analyzed including the laser emission and pulse laser ranging algorithm. An improved pulse ranging algorithm is developed. This new algorithm combines the matched filter algorithm and the constant fraction discrimination (CFD) algorithm. After the algorithm simulation, a laser ranging hardware system is set up to implement the improved algorithm. The laser ranging hardware system includes a laser diode, a laser detector and a high sample rate data logging circuit. Subsequently, using Verilog HDL language, the improved algorithm is implemented in the FPGA chip based on fusion of the matched filter algorithm and the CFD algorithm. Finally, the laser ranging experiment is carried out to test the improved algorithm ranging performance comparing to the matched filter algorithm and the CFD algorithm using the laser ranging hardware system. The test analysis result demonstrates that the laser ranging hardware system realized the high speed processing and high speed sampling data transmission. The algorithm analysis result presents that the improved algorithm achieves 0.3m distance ranging precision. The improved algorithm analysis result meets the expected effect, which is consistent with the theoretical simulation.
CN radical reactions with hydrogen cyanide and cyanogen - Comparison of theory and experiment
NASA Technical Reports Server (NTRS)
Yang, D. L.; Yu, T.; Lin, M. C.; Melius, C. F.
1992-01-01
The method of laser photolysis/laser-induced fluorescence is used to obtain absolute rate constants for CN radical reactions with HCN and C2N2. The rate constants were found to be temperature-dependent in the range 300-740 K and pressure independent in the range 100-600 Torr. Rice-Remsperger-Kassel-Marcus theory for both reactions employing the transition state parameters obtained by the BAC-MP4 method are made. These calculations yielded reasonable results for the CN + HCN reaction, predicting both the temperature dependence and pressure independence. No pressure effect was observed in the pressure range 100-1000 Torr at temperatures below 900 K, confirming the experimental results.
Magnetorheological fluids and applications to adaptive landing gear for a lightweight helicopter
NASA Astrophysics Data System (ADS)
Ahure-Powell, Louise A.
During hard landing or crash events of a helicopter there are impact loads that can be injurious to crew and other occupants as well as damaging to the helicopter structure. Landing gear systems are the first in line to protect crew and passengers from detrimental crash loads. The main focus of this research is to improve landing gear systems of a lightweight helicopter. Magnetorheological fluids (MRFs) provide potential solutions to several engineering challenges in a broad range of applications. One application that has been considered recently is the use of magnetorheological (MR) dampers in helicopter landing gear systems. In such application, the adaptive landing gear systems have to continuously adjust their stroking load in response to various operating conditions. In order to support this rotorcraft application, there is a necessity to validate that MRFs are qualified for landing gear applications. First, MRF composites, synthesized utilizing three hydraulic oils certified for use in landing gear systems, two average diameters of spherical magnetic particles, and a lecithin surfactant, are formulated to investigate their performance for potential use in a helicopter landing gear. The magnetorheology of these MR fluids is characterized through a range of tests, including (a) magnetorheology (yield stress and viscosity) as a function of magnetic field, (b) sedimentation analysis using an inductance-based sensor, (c) cycling of a small-scale MR damper undergoing sinusoidal excitations (at 2.5 and 5 Hz), and (d) impact testing of an MR damper for a range of magnetic field strengths and velocities using a free-flight drop tower facility. The performance of these MR fluids was analyzed, and their behavior was compared to standard commercial MR fluids. Based on this range of tests used to characterize the MR fluids synthesized, it was shown that it is feasible to utilize certified landing gear hydraulic oils as the carrier fluids to make suitable MR fluids. Another objective of this research is to satisfy the requirement of a helicopter landing gear damper to enable adaptive shock mitigation performance over a desired sink rate range. It was intended to maintain a constant stroking force of 17 793 N (4000 lbf) over a sink rate range of 1.8-7.9 m/s (6-26 ft/s), which is a substantial increase of the high-end of the sink rate range from 3.7 m/s (12 ft/s), in prior related work, to 7.9 m/s (26 ft/s). To achieve this increase in the high-end of the sink rate range, a spiral wave spring-assisted passive valve MR landing gear damper was developed. Drop tests were first conducted using a single MR landing gear damper. In order to maintain the peak stroking load constant over the desired sink rate range, a bang-bang current control algorithm was formulated using a force feedback signal. The controlled stroking loads were experimentally evaluated using a single drop damper test setup. To emulate the landing gear system of a lightweight helicopter, an iron bird drop test apparatus with four spiral wave spring-assisted relief valves MR landing gear dampers, was fabricated and successfully tested. The effectiveness of the proposed adaptive MR landing gear damper was theoretically and experimentally verified. The bang-bang current control algorithm successfully regulated the stroking load at 4000 lbf over a sink rate range of 6-22 ft/s in the iron bird tests, which significantly exceeds the sink rate range of the previous study (6-12 ft/s). The effectiveness of the proposed adaptive MR landing gear damper with a spiral wave spring-assisted passive valve is theoretically and experimentally verified.
Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Strugnell, Jan M; León, Rafael I; Semmens, Jayson M
2014-01-01
Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters.
Ramos, Jorge E.; Pecl, Gretta T.; Moltschaniwskyj, Natalie A.; Strugnell, Jan M.; León, Rafael I.; Semmens, Jayson M.
2014-01-01
Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters. PMID:25090250
Brown, Lydia; Bryant, Christina; Brown, Valerie; Bei, Bei; Judd, Fiona
2015-06-01
A large body of work has investigated the relationship between menopausal factors and negative well-being (e.g. anxiety and depressive symptoms), but less is known about positive well-being and its correlates among midlife women. This study tests two models with both positive and negative well-being indices as outcomes: the first included menopausal factors as predictors; the second model expanded the first by adding self-compassion, a protective trait, as a predictor and moderator. Cross-sectional study based on self-report questionnaires from 206 women aged 40-60, currently experiencing hot flushes. Hot flush interference ratings, emotional balance, satisfaction with life, eudaimonic well-being and depressive symptoms. In model one, menopausal stage and hot flush frequency were independent of well-being outcomes. Beliefs about perceived control over menopause was the strongest predictor of well-being (β range: .22-.32), followed by hot flush interference ratings (β range: .15-.33). In model two, self-compassion was the strongest predictor of well-being indices (β range: .20-.39), followed by beliefs about control (β range: .16-.20) and interference ratings (β range: .17-.26). Psychological aspects of the menopause appear more strongly linked to well-being than physiological aspects such as menopausal stage and hot flush frequency. Specifically, self-compassion, feeling in control of menopause and low interference ratings are three factors that are associated with well-being among midlife women. These aspects could be considered in tandem, as a means to support well-being in the context of menopause. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Heat transfer to small horizontal cylinders immersed in a fluidized bed
DOE Office of Scientific and Technical Information (OSTI.GOV)
Friedman, J.; Koundakjian, P.; Naylor, D.
2006-10-15
Heat transfer to horizontal cylinders immersed in fluidized beds has been extensively studied, but mainly in the context of heat transfer to boiler tubes in coal-fired beds. As a result, most correlations in the literature have been derived for cylinders of 25-50 mm diameter in vigorously fluidizing beds. In recent years, fluidized bed heat treating furnaces fired by natural gas have become increasingly popular, particularly in the steel wire manufacturing industry. These fluidized beds typically operate at relatively low fluidizing rates and with small diameter wires (1-6 mm). Nusselt number correlations developed based on boiler tube studies do not extrapolatemore » down to these small size ranges and low fluidizing rates. In order to obtain reliable Nusselt number data for these size ranges, an experimental investigation has been undertaken using two heat treating fluidized beds; one a pilot-scale industrial unit and the other a lab-scale (300 mm diameter) unit. Heat transfer measurements were obtained using resistively heated cylindrical samples ranging from 1.3 to 9.5 mm in diameter at fluidizing rates ranging from approximately 0.5 x G{sub mf} (packed bed condition) to over 10 x G{sub mf} using aluminum oxide sand particles ranging from d{sub p}=145-330 {mu}m (50-90 grit). It has been found that for all cylinder sizes tested, the Nusselt number reaches a maximum near 2 x G{sub mf}, then remains relatively steady ({+-}5-10%) to the maximum fluidizing rate tested, typically 8-12xG{sub mf}. A correlation for maximum Nusselt number is developed.« less
Tanaka, Jun; Kasai, Hidefumi; Shimizu, Kenji; Shimasaki, Shigeki; Kumagai, Yuji
2013-03-01
We performed a population pharmacokinetic analysis of phenytoin after intravenous administration of fosphenytoin sodium in healthy, neurosurgical, and epileptic subjects, including pediatric patients, and determined the optimal dose and infusion rate for achieving the therapeutic range. We used pooled data obtained from two phase I studies and one phase III study performed in Japan. The population pharmacokinetic analysis was performed using NONMEM software. The optimal dose and infusion rate were determined using simulation results obtained using the final model. The therapeutic range for total plasma phenytoin concentration is 10-20 μg/mL. We used a linear two-compartment model with conversion of fosphenytoin to phenytoin. Pharmacokinetic parameters of phenytoin, such as total clearance and central and peripheral volume of distribution were influenced by body weight. The dose simulations are as follows. In adult patients, the optimal dose and infusion rate of phenytoin for achieving the therapeutic range was 22.5 mg/kg and 3 mg/kg/min respectively. In pediatric patients, the total plasma concentration of phenytoin was within the therapeutic range for a shorter duration than that in adult patients at 22.5 mg/kg (3 mg/kg/min). However, many pediatric patients showed phenytoin concentration within the toxic range after administration of a dose of 30 mg/kg. The pharmacokinetics of phenytoin after intravenous administration of fosphenytoin sodium could be described using a linear two-compartment model. The administration of fosphenytoin sodium 22.5 mg/kg at an infusion rate of 3 mg/kg/min was optimal for achieving the desired plasma phenytoin concentration.
Edwards, Frances; Arkell, Paul; Fong; Roberts, Lesley M; Gendy, David; Wong, Christina Siew-Hie; Ngu, Joanna Chee Yien; Tiong, Lee Len; Bibi, Faridha Mohd Salleh; Lai, Lana Yin Hui; Ong, Tiong Kiam; Abouyannis, Michael
2014-01-01
Evidence is emerging that rates of adverse events in patients taking warfarin may vary with ethnicity. This study investigated the rates of bleeds and thromboembolic events, the international normalised ratio (INR) status and the relationship between INR and bleeding events in Malaysia. Patients attending INR clinic at the Heart Centre, Sarawak General Hospital were enrolled on an ad hoc basis from May 2010 and followed up for 1 year. At each routine visit, INR was recorded and screening for bleeding or thromboembolism occurred. Variables relating to INR control were used as predictors of bleeds in logistic regression models. 125 patients contributed to 140 person-years of follow-up. The rates of major bleed, thromboembolic event and minor bleed per 100 person-years of follow-up were 1.4, 0.75 and 34.3. The median time at target range calculated using the Rosendaal method was 61.6% (IQR 44.6–74.1%). Of the out-of-range readings, 30.0% were below range and 15.4% were above. INR variability, (standard deviation of individuals’ mean INR), was the best predictor of bleeding events, with an odds ratio of 3.21 (95% CI 1.10–9.38). Low rates of both major bleeds and thromboembolic events were recorded, in addition to a substantial number of INR readings under the recommended target range. This may suggest that the recommended INR ranges may not represent the optimal warfarin intensity for this population and that a lower intensity of therapy, as observed in this cohort, could be beneficial in preventing adverse events.
Gregson, Rachael Kathleen; Cole, Tim James; Skellett, Sophie; Bagkeris, Emmanouil; Welsby, Denise; Peters, Mark John
2017-05-01
To determine the effect of visual feedback on rate of chest compressions, secondarily relating the forces used. Randomised crossover trial. Tertiary teaching hospital. Fifty trained hospital staff. A thin sensor-mat placed over the manikin's chest measured rate and force. Rescuers applied compressions to the same paediatric manikin for two sessions. During one session they received visual feedback comparing their real-time rate with published guidelines. Primary: compression rate. Secondary: compression and residual forces. Rate of chest compressions (compressions per minute (compressions per minute; cpm)) varied widely (mean (SD) 111 (13), range 89-168), with a fourfold difference in variation during session 1 between those receiving and not receiving feedback (108 (5) vs 120 (20)). The interaction of session by feedback order was highly significant, indicating that this difference in mean rate between sessions was 14 cpm less (95% CI -22 to -5, p=0.002) in those given feedback first compared with those given it second. Compression force (N) varied widely (mean (SD) 306 (94); range 142-769). Those receiving feedback second (as opposed to first) used significantly lower force (adjusted mean difference -80 (95% CI -128 to -32), p=0.002). Mean residual force (18 N, SD 12, range 0-49) was unaffected by the intervention. While visual feedback restricted excessive compression rates to within the prescribed range, applied force remained widely variable. The forces required may differ with growth, but such variation treating one manikin is alarming. Feedback technologies additionally measuring force (effort) could help to standardise and define effective treatments throughout childhood. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Miniaturized GPS/MEMS IMU integrated board
NASA Technical Reports Server (NTRS)
Lin, Ching-Fang (Inventor)
2012-01-01
This invention documents the efforts on the research and development of a miniaturized GPS/MEMS IMU integrated navigation system. A miniaturized GPS/MEMS IMU integrated navigation system is presented; Laser Dynamic Range Imager (LDRI) based alignment algorithm for space applications is discussed. Two navigation cameras are also included to measure the range and range rate which can be integrated into the GPS/MEMS IMU system to enhance the navigation solution.
NASA Astrophysics Data System (ADS)
Katake, Anup; Choi, Heeyoul
2010-01-01
To enable autonomous air-to-refueling of manned and unmanned vehicles a robust high speed relative navigation sensor capable of proving high accuracy 3DOF information in diverse operating conditions is required. To help address this problem, StarVision Technologies Inc. has been developing a compact, high update rate (100Hz), wide field-of-view (90deg) direction and range estimation imaging sensor called VisNAV 100. The sensor is fully autonomous requiring no communication from the tanker aircraft and contains high reliability embedded avionics to provide range, azimuth, elevation (3 degrees of freedom solution 3DOF) and closing speed relative to the tanker aircraft. The sensor is capable of providing 3DOF with an error of 1% in range and 0.1deg in azimuth/elevation up to a range of 30m and 1 deg error in direction for ranges up to 200m at 100Hz update rates. In this paper we will discuss the algorithms that were developed in-house to enable robust beacon pattern detection, outlier rejection and 3DOF estimation in adverse conditions and present the results of several outdoor tests. Results from the long range single beacon detection tests will also be discussed.
Optimizing and Diversifying Electric Vehicle Driving Range for U.S. Drivers
Lin, Zhenhong
2014-08-11
Properly determining the driving range is critical for accurately predicting the sales and social benefits of battery electric vehicles (BEVs). This study proposes a framework for optimizing the driving range by minimizing the sum of battery price, electricity cost, and range limitation cost referred to as the "range-related cost" as a measurement of range anxiety. The objective function is linked to policy-relevant parameters, including battery cost and price markup, battery utilization, charging infrastructure availability, vehicle efficiency, electricity and gasoline prices, household vehicle ownership, daily driving patterns, discount rate, and perceived vehicle lifetime. Qualitative discussion of the framework and its empiricalmore » application to a sample (N=36664) representing new car drivers in the United States is included. The quantitative results strongly suggest that ranges of less than 100 miles are likely to be more popular in the BEV market for a long period of time. The average optimal range among U.S. drivers is found to be largely inelastic. Still, battery cost reduction significantly drives BEV demand toward longer ranges, whereas improvement in the charging infrastructure is found to significantly drive BEV demand toward shorter ranges. In conclusion, the bias of a single-range assumption and the effects of range optimization and diversification in reducing such biases are both found to be significant.« less
Optimizing and Diversifying Electric Vehicle Driving Range for U.S. Drivers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Zhenhong
Properly determining the driving range is critical for accurately predicting the sales and social benefits of battery electric vehicles (BEVs). This study proposes a framework for optimizing the driving range by minimizing the sum of battery price, electricity cost, and range limitation cost referred to as the "range-related cost" as a measurement of range anxiety. The objective function is linked to policy-relevant parameters, including battery cost and price markup, battery utilization, charging infrastructure availability, vehicle efficiency, electricity and gasoline prices, household vehicle ownership, daily driving patterns, discount rate, and perceived vehicle lifetime. Qualitative discussion of the framework and its empiricalmore » application to a sample (N=36664) representing new car drivers in the United States is included. The quantitative results strongly suggest that ranges of less than 100 miles are likely to be more popular in the BEV market for a long period of time. The average optimal range among U.S. drivers is found to be largely inelastic. Still, battery cost reduction significantly drives BEV demand toward longer ranges, whereas improvement in the charging infrastructure is found to significantly drive BEV demand toward shorter ranges. In conclusion, the bias of a single-range assumption and the effects of range optimization and diversification in reducing such biases are both found to be significant.« less
Laboratory Studies of Chemical and Photochemical Processes Relevant to Stratospheric Ozone
NASA Technical Reports Server (NTRS)
Villalta, P. W.; Zahniser, M. S.; Nelson, D. D.; Kolb, C. E.
1998-01-01
This is the final report for this project. Its purpose is to reduce the uncertainty in rate coefficients for key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring the rate coefficients for the reactions of HO2 + O3, and HO2 + NO2 in the temperature range (200-240 K) relevant to the lower stratosphere. In order to accomplish this, a high pressure turbulent flow tube reactor was built and its flow characteristics were quantified. The instrument was coupled with tunable diode laser spectroscopy for HO2 detection. Room temperature measurements of the HO2 + NO2 rate coefficients over the pressure range of 50-300 torr agree well with previous measurements. Preliminary measurements of the HO2 + O, rate coefficients at 50 - 300 Torr over the temperature range of 208-294 K agree with the NASA evaluation from 294-225 K but deviate significantly (50 % higher) at approximately 210 K.
Primary standards for measuring flow rates from 100 nl/min to 1 ml/min - gravimetric principle.
Bissig, Hugo; Petter, Harm Tido; Lucas, Peter; Batista, Elsa; Filipe, Eduarda; Almeida, Nelson; Ribeiro, Luis Filipe; Gala, João; Martins, Rui; Savanier, Benoit; Ogheard, Florestan; Niemann, Anders Koustrup; Lötters, Joost; Sparreboom, Wouter
2015-08-01
Microflow and nanoflow rate calibrations are important in several applications such as liquid chromatography, (scaled-down) process technology, and special health-care applications. However, traceability in the microflow and nanoflow range does not go below 16 μl/min in Europe. Furthermore, the European metrology organization EURAMET did not yet validate this traceability by means of an intercomparison between different National Metrology Institutes (NMIs). The NMIs METAS, Centre Technique des Industries Aérauliques et Thermiques, IPQ, Danish Technological Institute, and VSL have therefore developed and validated primary standards to cover the flow rate range from 0.1 μl/min to at least 1 ml/min. In this article, we describe the different designs and methods of the primary standards of the gravimetric principle and the results obtained at the intercomparison for the upper flow rate range for the various NMIs and Bronkhorst High-Tech, the manufacturer of the transfer standards used.
Study on improving the turbidity measurement of the absolute coagulation rate constant.
Sun, Zhiwei; Liu, Jie; Xu, Shenghua
2006-05-23
The existing theories dealing with the evaluation of the absolute coagulation rate constant by turbidity measurement were experimentally tested for different particle-sized (radius = a) suspensions at incident wavelengths (lambda) ranging from near-infrared to ultraviolet light. When the size parameter alpha = 2pi a/lambda > 3, the rate constant data from previous theories for fixed-sized particles show significant inconsistencies at different light wavelengths. We attribute this problem to the imperfection of these theories in describing the light scattering from doublets through their evaluation of the extinction cross section. The evaluations of the rate constants by all previous theories become untenable as the size parameter increases and therefore hampers the applicable range of the turbidity measurement. By using the T-matrix method, we present a robust solution for evaluating the extinction cross section of doublets formed in the aggregation. Our experiments show that this new approach is effective in extending the applicability range of the turbidity methodology and increasing measurement accuracy.
The Features of Fracture Behavior of an Aluminum-Magnesium Alloy AMg6 Under High-Rate Straining
NASA Astrophysics Data System (ADS)
Skripnyak, N. V.
2015-09-01
The results of investigation of fracture dynamics of rolled sheet specimens of an AMg6 alloy are presented for the range of strain rates from 10-3 to 103 s-1. It is found out that the presence of nanostructured surface layers on the thin AMg6 rolled sheets results in improved strength characteristics within the above range of strain rates. A modified model of a deforming medium is proposed to describe the plastic flow and fracture of the AMg6 alloy.
Influence of diurnal variations in stream temperature on streamflow loss and groundwater recharge
Constantz, Jim; Thomas, Carole L.; Zellweger, Gary W.
1994-01-01
We demonstrate that for losing reaches with significant diurnal variations in stream temperature, the effect of stream temperature on streambed seepage is a major factor contributing to reduced afternoon streamflows. An explanation is based on the effect of stream temperature on the hydraulic conductivity of the streambed, which can be expected to double in the 0° to 25°C temperature range. Results are presented for field experiments in which stream discharge and temperature were continuously measured for several days over losing reaches at St. Kevin Gulch, Colorado, and Tijeras Arroyo, New Mexico. At St. Kevin Gulch in July 1991, the diurnal stream temperature in the 160-m study reach ranged from about 4° to 18°C, discharges ranged from 10 to 18 L/s, and streamflow loss in the study reach ranged from 2.7 to 3.7 L/s. On the basis of measured stream temperature variations, the predicted change in conductivity was about 38%; the measured change in stream loss was about 26%, suggesting that streambed temperature varied less than the stream temperature. At Tijeras Arroyo in May 1992, diurnal stream temperature in the 655-m study reach ranged from about 10° to 25°C and discharge ranged from 25 to 55 L/s. Streamflow loss was converted to infiltration rates by factoring in the changing stream reach surface area and streamflow losses due to evaporation rates as measured in a hemispherical evaporation chamber. Infiltration rates ranged from about 0.7 to 2.0 m/d, depending on time and location. Based on measured stream temperature variations, the predicted change in conductivity was 29%; the measured change in infiltration was also about 27%. This suggests that high infiltration rates cause rapid convection of heat to the streambed. Evapotranspiration losses were estimated for the reach and adjacent flood plain within the arroyo. On the basis of these estimates, only about 5% of flow loss was consumed via stream evaporation and stream-side evapotranspiration, indicating that 95% of the loss within the study reach represented groundwater recharge.
Flow range enhancement by secondary flow effect in low solidity circular cascade diffusers
NASA Astrophysics Data System (ADS)
Sakaguchi, Daisaku; Tun, Min Thaw; Mizokoshi, Kanata; Kishikawa, Daiki
2014-08-01
High-pressure ratio and wide operating range are highly required for compressors and blowers. The technical issue of the design is achievement of suppression of flow separation at small flow rate without deteriorating the efficiency at design flow rate. A numerical simulation is very effective in design procedure, however, cost of the numerical simulation is generally high during the practical design process, and it is difficult to confirm the optimal design which is combined with many parameters. A multi-objective optimization technique is the idea that has been proposed for solving the problem in practical design process. In this study, a Low Solidity circular cascade Diffuser (LSD) in a centrifugal blower is successfully designed by means of multi-objective optimization technique. An optimization code with a meta-model assisted evolutionary algorithm is used with a commercial CFD code ANSYS-CFX. The optimization is aiming at improving the static pressure coefficient at design point and at low flow rate condition while constraining the slope of the lift coefficient curve. Moreover, a small tip clearance of the LSD blade was applied in order to activate and to stabilize the secondary flow effect at small flow rate condition. The optimized LSD blade has an extended operating range of 114 % towards smaller flow rate as compared to the baseline design without deteriorating the diffuser pressure recovery at design point. The diffuser pressure rise and operating flow range of the optimized LSD blade are experimentally verified by overall performance test. The detailed flow in the diffuser is also confirmed by means of a Particle Image Velocimeter. Secondary flow is clearly captured by PIV and it spreads to the whole area of LSD blade pitch. It is found that the optimized LSD blade shows good improvement of the blade loading in the whole operating range, while at small flow rate the flow separation on the LSD blade has been successfully suppressed by the secondary flow effect.
Listeners' identification and discrimination of digitally manipulated sounds as prolongations.
Kawai, Norimune; Healey, E Charles; Carrell, Thomas D
2007-08-01
The present study had two main purposes. One was to examine if listeners perceive gradually increasing durations of a voiceless fricative categorically ("fluent" versus "stuttered") or continuously (gradient perception from fluent to stuttered). The second purpose was to investigate whether there are gender differences in how listeners perceive various duration of sounds as "prolongations." Forty-four listeners were instructed to rate the duration of the // in the word "shape" produced by a normally fluent speaker. The target word was embedded in the middle of an experimental phrase and the initial // sound was digitally manipulated to create a range of fluent to stuttered sounds. This was accomplished by creating 20 ms stepwise increments for sounds ranging from 120 to 500 ms in duration. Listeners were instructed to give a rating of 1 for a fluent word and a rating of 100 for a stuttered word. The results showed listeners perceived the range of sounds continuously. Also, there was a significant gender difference in that males rated fluent sounds higher than females but female listeners rated stuttered sounds higher than males. The implications of these results are discussed.
Linking seasonal home range size with habitat selection and movement in a mountain ungulate.
Viana, Duarte S; Granados, José Enrique; Fandos, Paulino; Pérez, Jesús M; Cano-Manuel, Francisco Javier; Burón, Daniel; Fandos, Guillermo; Aguado, María Ángeles Párraga; Figuerola, Jordi; Soriguer, Ramón C
2018-01-01
Space use by animals is determined by the interplay between movement and the environment, and is thus mediated by habitat selection, biotic interactions and intrinsic factors of moving individuals. These processes ultimately determine home range size, but their relative contributions and dynamic nature remain less explored. We investigated the role of habitat selection, movement unrelated to habitat selection and intrinsic factors related to sex in driving space use and home range size in Iberian ibex, Capra pyrenaica . We used GPS collars to track ibex across the year in two different geographical areas of Sierra Nevada, Spain, and measured habitat variables related to forage and roost availability. By using integrated step selection analysis (iSSA), we show that habitat selection was important to explain space use by ibex. As a consequence, movement was constrained by habitat selection, as observed displacement rate was shorter than expected under null selection. Selection-independent movement, selection strength and resource availability were important drivers of seasonal home range size. Both displacement rate and directional persistence had a positive relationship with home range size while accounting for habitat selection, suggesting that individual characteristics and state may also affect home range size. Ibex living at higher altitudes, where resource availability shows stronger altitudinal gradients across the year, had larger home ranges. Home range size was larger in spring and autumn, when ibex ascend and descend back, and smaller in summer and winter, when resources are more stable. Therefore, home range size decreased with resource availability. Finally, males had larger home ranges than females, which might be explained by differences in body size and reproductive behaviour. Movement, selection strength, resource availability and intrinsic factors related to sex determined home range size of Iberian ibex. Our results highlight the need to integrate and account for process dependencies, here the interdependence of movement and habitat selection, to understand how animals use space. This study contributes to understand how movement links environmental and geographical space use and determines home range behaviour in large herbivores.
Rating of personality disorder features in popular movie characters.
Hesse, Morten; Schliewe, Sanna; Thomsen, Rasmus R
2005-12-08
Tools for training professionals in rating personality disorders are few. We present one such tool: rating of fictional persons. However, before ratings of fictional persons can be useful, we need to know whether raters get the same results, when rating fictional characters. Psychology students at the University of Copenhagen (N = 8) rated four different movie characters from four movies based on three systems: Global rating scales representing each of the 10 personality disorders in the DSM-IV, a criterion list of all criteria for all DSM-IV personality disorders in random order, and the Ten Item Personality Inventory for rating the five-factor model. Agreement was estimated based on intraclass-correlation. Agreement for rating scales for personality disorders ranged from 0.04 to 0.54. For personality disorder features based on DSM-IV criteria, agreement ranged from 0.24 to 0.89, and agreement for the five-factor model ranged from 0.05 to 0.88. The largest multivariate effect was observed for criteria count followed by the TIPI, followed by rating scales. Raters experienced personality disorder criteria as the easiest, and global personality disorder scales as the most difficult, but with significant variation between movies. Psychology students with limited or no clinical experience can agree well on the personality traits of movie characters based on watching the movie. Rating movie characters may be a way to practice assessment of personality.
Rating of personality disorder features in popular movie characters
Hesse, Morten; Schliewe, Sanna; Thomsen, Rasmus R
2005-01-01
Background Tools for training professionals in rating personality disorders are few. We present one such tool: rating of fictional persons. However, before ratings of fictional persons can be useful, we need to know whether raters get the same results, when rating fictional characters. Method Psychology students at the University of Copenhagen (N = 8) rated four different movie characters from four movies based on three systems: Global rating scales representing each of the 10 personality disorders in the DSM-IV, a criterion list of all criteria for all DSM-IV personality disorders in random order, and the Ten Item Personality Inventory for rating the five-factor model. Agreement was estimated based on intraclass-correlation. Results Agreement for rating scales for personality disorders ranged from 0.04 to 0.54. For personality disorder features based on DSM-IV criteria, agreement ranged from 0.24 to 0.89, and agreement for the five-factor model ranged from 0.05 to 0.88. The largest multivariate effect was observed for criteria count followed by the TIPI, followed by rating scales. Raters experienced personality disorder criteria as the easiest, and global personality disorder scales as the most difficult, but with significant variation between movies. Conclusion Psychology students with limited or no clinical experience can agree well on the personality traits of movie characters based on watching the movie. Rating movie characters may be a way to practice assessment of personality. PMID:16336663
Celler, Branko; Argha, Ahmadreza; Varnfield, Marlien; Jayasena, Rajiv
2018-04-09
In a home telemonitoring trial, patient adherence with scheduled vital signs measurements is an important aspect that has not been thoroughly studied and for which data in the literature are limited. Levels of adherence have been reported as varying from approximately 40% to 90%, and in most cases, the adherence rate usually dropped off steadily over time. This drop is more evident in the first few weeks or months after the start. Higher adherence rates have been reported for simple types of monitoring and for shorter periods of intervention. If patients do not follow the intended procedure, poorer results than expected may be achieved. Hence, analyzing factors that can influence patient adherence is of great importance. The goal of the research was to present findings on patient adherence with scheduled vital signs measurements in the recently completed Commonwealth Scientific and Industrial Research Organisation (CSIRO) national trial of home telemonitoring of patients (mean age 70.5 years, SD 9.3 years) with chronic conditions (chronic obstructive pulmonary disease, coronary artery disease, hypertensive diseases, congestive heart failure, diabetes, or asthma) carried out at 5 locations along the east coast of Australia. We investigated the ability of chronically ill patients to carry out a daily schedule of vital signs measurements as part of a chronic disease management care plan over periods exceeding 6 months (302 days, SD 135 days) and explored different levels of adherence for different measurements as a function of age, gender, and supervisory models. In this study, 113 patients forming the test arm of a Before and After Control Intervention (BACI) home telemonitoring trial were analyzed. Patients were required to monitor on a daily basis a range of vital signs determined by their chronic condition and comorbidities. Vital signs included noninvasive blood pressure, pulse oximetry, spirometry, electrocardiogram (ECG), blood glucose level, body temperature, and body weight. Adherence was calculated as the number of days during which at least 1 measurement was taken over all days where measurements were scheduled. Different levels of adherence for different measurements, as a function of age, gender, and supervisory models, were analyzed using linear regression and analysis of covariance for a period of 1 year after the intervention. Patients were monitored on average for 302 (SD 135) days, although some continued beyond 12 months. The overall adherence rate for all measurements was 64.1% (range 59.4% to 68.8%). The adherence rates of patients monitored in hospital settings relative to those monitored in community settings were significantly higher for spirometry (69.3%, range 60.4% to 78.2%, versus 41.0%, range 33.1% to 49.0%, P<.001), body weight (64.5%, range 55.7% to 73.2%, versus 40.5%, range 32.3% to 48.7%, P<.001), and body temperature (66.8%, range 59.7% to 73.9%, versus 55.2%, range 48.4% to 61.9%, P=.03). Adherence with blood glucose measurements (58.1%, range 46.7% to 69.5%, versus 50.2%, range 42.8% to 57.6%, P=.24) was not significantly different overall. Adherence rates for blood pressure (68.5%, range 62.7% to 74.2%, versus 59.7%, range 52.1% to 67.3%, P=.04), ECG (65.6%, range 59.7% to 71.5%, versus 56.5%, range 48.7% to 64.4%, P=.047), and pulse oximetry (67.0%, range 61.4% to 72.7%, versus 56.4%, range 48.6% to 64.1%, P=.02) were significantly higher in males relative to female subjects. No statistical differences were observed between rates of adherence for the younger patient group (70 years and younger) and older patient group (older than 70 years). Patients with chronic conditions enrolled in the home telemonitoring trial were able to record their vital signs at home at least once every 2 days over prolonged periods of time. Male patients maintained a higher adherence than female patients over time, and patients supervised by hospital-based care coordinators reported higher levels of adherence with their measurement schedule relative to patients supervised in community settings. This was most noticeable for spirometry. Australian New Zealand Clinical Trials Registry ACTRN12613000635763; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364030&isReview=true (Archived by WebCite at http://www.webcitation.org/6xPOU3DpR). ©Branko Celler, Ahmadreza Argha, Marlien Varnfield, Rajiv Jayasena. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 09.04.2018.
2018-01-01
Background In a home telemonitoring trial, patient adherence with scheduled vital signs measurements is an important aspect that has not been thoroughly studied and for which data in the literature are limited. Levels of adherence have been reported as varying from approximately 40% to 90%, and in most cases, the adherence rate usually dropped off steadily over time. This drop is more evident in the first few weeks or months after the start. Higher adherence rates have been reported for simple types of monitoring and for shorter periods of intervention. If patients do not follow the intended procedure, poorer results than expected may be achieved. Hence, analyzing factors that can influence patient adherence is of great importance. Objective The goal of the research was to present findings on patient adherence with scheduled vital signs measurements in the recently completed Commonwealth Scientific and Industrial Research Organisation (CSIRO) national trial of home telemonitoring of patients (mean age 70.5 years, SD 9.3 years) with chronic conditions (chronic obstructive pulmonary disease, coronary artery disease, hypertensive diseases, congestive heart failure, diabetes, or asthma) carried out at 5 locations along the east coast of Australia. We investigated the ability of chronically ill patients to carry out a daily schedule of vital signs measurements as part of a chronic disease management care plan over periods exceeding 6 months (302 days, SD 135 days) and explored different levels of adherence for different measurements as a function of age, gender, and supervisory models. Methods In this study, 113 patients forming the test arm of a Before and After Control Intervention (BACI) home telemonitoring trial were analyzed. Patients were required to monitor on a daily basis a range of vital signs determined by their chronic condition and comorbidities. Vital signs included noninvasive blood pressure, pulse oximetry, spirometry, electrocardiogram (ECG), blood glucose level, body temperature, and body weight. Adherence was calculated as the number of days during which at least 1 measurement was taken over all days where measurements were scheduled. Different levels of adherence for different measurements, as a function of age, gender, and supervisory models, were analyzed using linear regression and analysis of covariance for a period of 1 year after the intervention. Results Patients were monitored on average for 302 (SD 135) days, although some continued beyond 12 months. The overall adherence rate for all measurements was 64.1% (range 59.4% to 68.8%). The adherence rates of patients monitored in hospital settings relative to those monitored in community settings were significantly higher for spirometry (69.3%, range 60.4% to 78.2%, versus 41.0%, range 33.1% to 49.0%, P<.001), body weight (64.5%, range 55.7% to 73.2%, versus 40.5%, range 32.3% to 48.7%, P<.001), and body temperature (66.8%, range 59.7% to 73.9%, versus 55.2%, range 48.4% to 61.9%, P=.03). Adherence with blood glucose measurements (58.1%, range 46.7% to 69.5%, versus 50.2%, range 42.8% to 57.6%, P=.24) was not significantly different overall. Adherence rates for blood pressure (68.5%, range 62.7% to 74.2%, versus 59.7%, range 52.1% to 67.3%, P=.04), ECG (65.6%, range 59.7% to 71.5%, versus 56.5%, range 48.7% to 64.4%, P=.047), and pulse oximetry (67.0%, range 61.4% to 72.7%, versus 56.4%, range 48.6% to 64.1%, P=.02) were significantly higher in males relative to female subjects. No statistical differences were observed between rates of adherence for the younger patient group (70 years and younger) and older patient group (older than 70 years). Conclusions Patients with chronic conditions enrolled in the home telemonitoring trial were able to record their vital signs at home at least once every 2 days over prolonged periods of time. Male patients maintained a higher adherence than female patients over time, and patients supervised by hospital-based care coordinators reported higher levels of adherence with their measurement schedule relative to patients supervised in community settings. This was most noticeable for spirometry. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN12613000635763; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364030&isReview=true (Archived by WebCite at http://www.webcitation.org/6xPOU3DpR). PMID:29631991
NASA Technical Reports Server (NTRS)
Somogyi, Dezso; Feiler, Charles E.
1960-01-01
The initial rates of heat release produced by the reactions of hydrazine and unsymmetrical dimethylhydrazine with nitric acid were determined in a bomb calorimeter under conditions of forced mixing. Fuel-oxidant weight ratio and injection velocity were varied. The rate of heat release apparently depended on the interfacial area between the propellants. Above a narrow range of injection velocities representing a critical amount of interfacial area, the rates reached a maximum and were almost constant with injection velocity. The maximum rate for hydrazine was about 70 percent greater than that for unsymmetrical dimethylhydrazine. The total heat released did not vary with mixture ratio over the range studied.
Cooling Rate Determination in Additively Manufactured Aluminum Alloy 2219
NASA Astrophysics Data System (ADS)
Brice, Craig A.; Dennis, Noah
2015-05-01
Metallic additive manufacturing processes generally utilize a conduction mode, welding-type approach to create beads of deposited material that can be arranged into a three-dimensional structure. As with welding, the cooling rates in the molten pool are relatively rapid compared to traditional casting techniques. Determination of the cooling rate in the molten pool is critical for predicting the solidified microstructure and resultant properties. In this experiment, wire-fed electron beam additive manufacturing was used to melt aluminum alloy 2219 under different thermal boundary conditions. The dendrite arm spacing was measured in the remelted material, and this information was used to estimate cooling rates in the molten pool based on established empirical relationships. The results showed that the thermal boundary conditions have a significant effect on the resulting cooling rate in the molten pool. When thermal conduction is limited due to a small thermal sink, the dendrite arm spacing varies between 15 and 35 µm. When thermal conduction is active, the dendrite arm spacing varies between 6 and 12 µm. This range of dendrite arm spacing implies cooling rates ranging from 5 to 350 K/s. Cooling rates can vary greatly as thermal conditions change during deposition. A cooling rate at the higher end of the range could lead to significant deviation from microstructural equilibrium during solidification.
NASA Astrophysics Data System (ADS)
Rizvi, S. Tauqeer ul Islam; Linshu, He; ur Rehman, Tawfiq; Rafique, Amer Farhan
2012-11-01
A numerical optimization study of lifting body re-entry vehicles is presented for nominal as well as shallow entry conditions for Medium and Intermediate Range applications. Due to the stringent requirement of a high degree of accuracy for conventional vehicles, lifting re-entry can be used to attain the impact at the desired terminal flight path angle and speed and thus can potentially improve accuracy of the re-entry vehicle. The re-entry of a medium range and intermediate range vehicles is characterized by very high negative flight path angle and low re-entry speed as compared to a maneuverable re-entry vehicle or a common aero vehicle intended for an intercontinental range. Highly negative flight path angles at the re-entry impose high dynamic pressure as well as heat loads on the vehicle. The trajectory studies are carried out to maximize the cross range of the re-entry vehicle while imposing a maximum dynamic pressure constraint of 350 KPa with a 3 MW/m2 heat rate limit. The maximum normal acceleration and the total heat load experienced by the vehicle at the stagnation point during the maneuver have been computed for the vehicle for possible future conceptual design studies. It has been found that cross range capability of up to 35 km can be achieved with a lifting-body design within the heat rate and the dynamic pressure boundary at normal entry conditions. For shallow entry angle of -20 degree and intermediate ranges a cross range capability of up to 250 km can be attained for a lifting body design with less than 10 percent loss in overall range. The normal acceleration also remains within limits. The lifting-body results have also been compared with wing-body results at shallow entry condition. An hp-adaptive pseudo-spectral method has been used for constrained trajectory optimization.
A Macrophysiological Analysis of Energetic Constraints on Geographic Range Size in Mammals
Ceballos, Gerardo; Steele, Michael A.
2013-01-01
Physiological processes are essential for understanding the distribution and abundance of organisms, and recently, with widespread attention to climate change, physiology has been ushered back to the forefront of ecological thinking. We present a macrophysiological analysis of the energetics of geographic range size using combined data on body size, basal metabolic rate (BMR), phylogeny and range properties for 574 species of mammals. We propose three mechanisms by which interspecific variation in BMR should relate positively to geographic range size: (i) Thermal Plasticity Hypothesis, (ii) Activity Levels/Dispersal Hypothesis, and (iii) Energy Constraint Hypothesis. Although each mechanism predicts a positive correlation between BMR and range size, they can be further distinguished based on the shape of the relationship they predict. We found evidence for the predicted positive relationship in two dimensions of energetics: (i) the absolute, mass-dependent dimension (BMR) and (ii) the relative, mass-independent dimension (MIBMR). The shapes of both relationships were similar and most consistent with that expected from the Energy Constraint Hypothesis, which was proposed previously to explain the classic macroecological relationship between range size and body size in mammals and birds. The fact that this pattern holds in the MIBMR dimension indicates that species with supra-allometric metabolic rates require among the largest ranges, above and beyond the increasing energy demands that accrue as an allometric consequence of large body size. The relationship is most evident at high latitudes north of the Tropics, where large ranges and elevated MIBMR are most common. Our results suggest that species that are most vulnerable to extinction from range size reductions are both large-bodied and have elevated MIBMR, but also, that smaller species with elevated MIBMR are at heightened risk. We also provide insights into the global latitudinal trends in range size and MIBMR and more general issues of phylogenetic and geographic scale. PMID:24058444
Radar echo processing with partitioned de-ramp
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dubbert, Dale F.; Tise, Bertice L.
2013-03-19
The spurious-free dynamic range of a wideband radar system is increased by apportioning de-ramp processing across analog and digital processing domains. A chirp rate offset is applied between the received waveform and the reference waveform that is used for downconversion to the intermediate frequency (IF) range. The chirp rate offset results in a residual chirp in the IF signal prior to digitization. After digitization, the residual IF chirp is removed with digital signal processing.
Cardiovascular and Thermal Strain during Manual Work in Cold Weather
2005-05-01
subjective thermal sensation (on a scale ranging from unbearably cold to very hot) and thermal comfort (ranging from comfortable to extremely uncomfortable...both thermal sensation and thermal comfort ratings at 1 and at 30 min. There was no significant difference in Thermal Comfort (TC) between the two...overview of the subjective thermal ratings pre and post repeated cold exposure is shown in Table 2. During the acclimation days, thermal comfort was
Photovoltaic power system tests on an 8-kilowatt single-phase line-commutated inverter
NASA Technical Reports Server (NTRS)
Stover, J. B.
1978-01-01
Efficiency and power factor were measured as functions of solar array voltage and current. The effects of input shunt capacitance and series inductance were determined. Tests were conducted from 15 to 75 percent of the 8 kW rated inverter input power. Measured efficiencies ranged from 76 percent to 88 percent at about 50 percent of rated inverter input power. Power factor ranged from 36 percent to 72 percent.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vriens, L.; Smeets, A.H.M.
1980-09-01
For electron-induced ionization, excitation, and de-excitation, mainly from excited atomic states, a detailed analysis is presented of the dependence of the cross sections and rate coefficients on electron energy and temperature, and on atomic parameters. A wide energy range is covered, including sudden as well as adiabatic collisions. By combining the available experimental and theoretical information, a set of simple analytical formulas is constructed for the cross sections and rate coefficients of the processes mentioned, for the total depopulation, and for three-body recombination. The formulas account for large deviations from classical and semiclassical scaling, as found for excitation. They agreemore » with experimental data and with the theories in their respective ranges of validity, but have a wider range of validity than the separate theories. The simple analytical form further facilitates the application in plasma modeling.« less
NASA Technical Reports Server (NTRS)
Lerch, Bradley A.; Arnold, Steven M.
2014-01-01
In support of an effort on damage prognosis, the viscoelastic behavior of Ti-6Al-4V (Ti-6-4) was investigated. This report documents the experimental characterization of this titanium alloy. Various uniaxial tests were conducted to low load levels over the temperature range of 20 to 538 C to define tensile, creep, and relaxation behavior. A range of strain rates (6x10(exp -7) to 0.001/s) were used to document rate effects. All tests were designed to include an unloading portion, followed by a hold time at temperature to allow recovery to occur either at zero stress or strain. The titanium alloy was found to exhibit viscoelastic behavior below the "yield" point and over the entire range of temperatures (although at lower temperatures the magnitude is extremely small). These experimental data will be used for future characterization of a viscoelastic model.
3He(α, γ)7Be cross section in a wide energy range
NASA Astrophysics Data System (ADS)
Szücs, Tamás; Gyürky, György; Halász, Zoltán; Kiss, Gábor Gy.; Fülöp, Zsolt
2018-01-01
The reaction rate of the 3He(α,γ)7 Be reaction is important both in the Big Bang Nucleosynthesis (BBN) and in the Solar hydrogen burning. There have been a lot of experimental and theoretical efforts to determine this reaction rate with high precision. Some long standing issues have been solved by the more precise investigations, like the different S(0) values predicted by the activation and in-beam measurement. However, the recent, more detailed astrophysical model predictions require the reaction rate with even higher precision to unravel new issues like the Solar composition. One way to increase the precision is to provide a comprehensive dataset in a wide energy range, extending the experimental cross section database of this reaction. This paper presents a new cross section measurement between Ecm = 2.5 - 4.4 MeV, in an energy range which extends above the 7Be proton separation threshold.
Are pound and euro the same currency?
NASA Astrophysics Data System (ADS)
Matsushita, Raul; Gleria, Iram; Figueiredo, Annibal; da Silva, Sergio
2007-08-01
Based on long-range dependence, some analysts claim that the exchange rate time series of the pound sterling and of an artificially extended euro have been locked together for years despite daily changes [M. Ausloos, K. Ivanova, Physica A 286 (2000) 353; K. Ivanova, M. Ausloos, False EUR exchange rates vs DKK, CHF, JPY and USD. What is a strong currency? in: H. Takayasu (Ed.), Empirical Sciences in Financial Fluctuations: The Advent of Econophysics, Springer-Verlag, Berlin, 2002, pp. 62 76]. They conclude that pound and euro are in practice the same currency. We assess the long-range dependence over time through Hurst exponents of pound dollar and extended euro dollar exchange rates employing three alternative techniques, namely rescaled range analysis, detrended fluctuation analysis, and detrended moving average. We find the result above (which is based on detrended fluctuation analysis) not to be robust to the changing techniques and parameterizing.
Physical Controls on Delta Formation and Carbon Storage in Mountain Lakes
NASA Astrophysics Data System (ADS)
Scott, D.; Wohl, E.
2014-12-01
Carbon acts as a component in greenhouse gases that regulate global climate. It is imperative to understand the transport and storage of carbon in order to understand and manage climate change. We examine terrestrial carbon storage in mountain lake deltas as a way of furthering our understanding of the terrestrial carbon sink, which is a poorly understood but significant contributor to the global carbon cycle. We examined subalpine lake deltas in the Washington Cascade Range and Colorado Front Range to test the following hypotheses: 1) The size of the deltaic carbon sink is strongly correlated with incision at the outlet of the lake and the topography of the basin. 2) Areas of high exhumation rates will have smaller and fewer deltas because a high exhumation rate should lead to more confined basins and more colluvium available to dam lake outlets, preventing lake level drop and corresponding delta formation. 3) High-energy deltas will transport more carbon to lakes, avoiding the deltaic carbon sink. At 27 lakes, we surveyed mountain lake deltas and took sediment samples, surveyed lake outlets in the field, and measured lake valley confinement in GIS to test hypotheses 1 and 3. Across the Snoqualmie and Skykomish watersheds in the Washington Cascades and the Colorado Front Range, we took a census of the number of natural lakes and the proportion of those lakes with deltas to test hypothesis 2. Preliminary results indicate that the Washington Cascades (high exhumation rate) have a higher density of lakes, but fewer deltas, than the Colorado Front Range (low exhumation rate). We also suspect that deltas in the Washington Cascades will have a lower carbon content than the Colorado Front Range due to generally higher energy levels on deltas. Finally, we found a substantial difference in the geomorphology and sediment type between beaver-affected and non-beaver-affected lakes in the Colorado Front Range.
An airborne low SWaP-C UAS sense and avoid system
NASA Astrophysics Data System (ADS)
Wang, Zhonghai; Lin, Xingping; Xiang, Xingyu; Blasch, Erik; Pham, Khanh; Chen, Genshe; Shen, Dan; Jia, Bin; Wang, Gang
2016-05-01
This paper presents a low size, weight and power - cost (SWaP-C) airborne sense and avoid (ABSAA) system, which is based on a linear frequency modulated continuous wave (LFMCW) radar and can be mounted on small unmanned aircraft system (UAS). The system satisfies the constraint of the available sources on group 2/3 UAS. To obtain the desired sense and avoid range, a narrow band frequency (or range) scanning technique is applied for reducing the receiver's noise floor to improve its sensitivity, and a digital signal integration with fast Fourier transform (FFT) is applied to enhance the signal to noise ratio (SNR). The gate length and chirp rate are intelligently adapted to not only accommodate different object distances, speeds and approaching angle conditions, but also optimize the detection speed, resolution and coverage range. To minimize the radar blind zone, a higher chirp rate and a narrowband intermediate frequency (IF) filter are applied at the near region with a single antenna signal for target detection. The offset IF frequency between transmitter (TX) and receiver (RX) is designed to mitigate the TX leakage to the receiver, especially at close distances. Adaptive antenna gain and beam-width are utilized for searching at far distance and fast 360 degree middle range. For speeding up the system update rate, lower chirp rates and wider IF and baseband filters are applied for obtaining larger range scanning step length out of the near region. To make the system working with a low power transmitter (TX), multiple-antenna beamforming, digital signal integration with FFT, and a much narrower receiver (RX) bandwidth are applied at the far region. The ABSAA system working range is 2 miles with a 1W transmitter and single antenna signal detection, and it is 5 miles when a 5W transmitter and 4-antenna beamforming (BF) are applied.
Survivorship analysis of Cotrel-Dubousset instrumentation in idiopathic scoliosis.
Bago, J; Ramirez, M; Pellise, F; Villanueva, C
2003-08-01
This study presents a survivorship analysis of Cotrel-Dubousset instrumentation in the surgical treatment of idiopathic scoliosis. Between 1987 and 1995, a total of 133 patients with idiopathic scoliosis received posterior spine fusion and instrumentation with the CD system at our center. The patients' mean age at surgery was 16.5 years (range 11-43 years). The magnitude of the thoracic scoliosis averaged 62.7 degrees (range 40 degrees -125 degrees ) and that of the lumbar curve was 58.8 degrees (range 40 degrees -100 degrees ). On average, 12.2 segments were fused (range 8-17) and, excluding the rods, 14.1 implants were set for each patient (range 10-21). Survivorship analysis was carried out using the Kaplan-Meier method. Implant removal was considered the terminal event, or "death". The effect of several variables on survival rate was determined with the Cox regression method. The patients remained in the study for 56.7 months (range 2-120 months). One-hundred and ten patients were withdrawn ("censored"): 90 "alive" (did not require repeat surgery and attended follow-up control in 1997) and 20 "lost" (did not attend control in 1997). Twenty-three patients attained the terminal event of implant removal for a variety of reasons: acute infection (three cases), late infection (ten cases), implant failure requiring revision (six cases) and local pain (four cases). The survival rate was 95.5% at 3 months, 94.7% at 6 months, 93.9% at 1 year, 91.5% at 2 years, 82.2% at 5 years and 76.5% at 10 years. The magnitude of the curves, total number of implants and number of fused segments did not correlate with survival probability. A positive correlation was found between survival rate and correction loss between surgery and last control. A survival rate of 76.5% at 10 years is unexpectedly low. Current data suggest that the incapacity to maintain correction after initial surgery plays a major roll in the long-term evolution of Cotrel-Dubousset instrumentation.
Trapping of CH4, CO, and CO2 in Amorphous Water Ice
NASA Astrophysics Data System (ADS)
Mastrapa, R. M. E.; Brown, R. H.; Anicich, V. G.; Cohen, B. A.; Dai, W.; Lunine, J. I.
1999-09-01
In this study, CO, CH4, and CO2 were trapped in H2O at temperatures as low as 20 K and pressures between 10-5 and 10-8 Torr. IR spectra were taken of each sample before sublimation to confirm the presence of volatiles. The samples were then heated at rates from 0.25 K/min to 1 K/min and the escape ranges were measured with a mass spectrometer. The volatiles escaped from the ice mixtures in temperature ranges similar to those found in previous work (1, 2, 3), namely 48-52 K, 145-160 K, 170-185 K. H2O is released from 150 K to 185 K. However, the temperature range of escape is strongly dependent on deposition temperature and heating rate. If the deposition temperature is below the point where the solid volatile rapidly sublimates in the ambient environment of our experiment, then the first range of volatile escape is centered around it's sublimation point, and there is little of the volatile remaining from 170-185 K. The location of the third escape range shifts to lower temperatures with slower sublimation rate. It was determined that 0.5 K/min is the ideal sample heating rate to determine these escape ranges. In our data, the infrared spectrum of CO trapped in water ice shows a splitting of the 2145 cm-1 solid CO line into two bands at 2343 cm-1 and 2135 cm-1. These shifts are similar to those seen by Sandford, et al. (4). (1) Bar-Nun, A., G. Herman, D. Laufer, and M. L. Rappaport, (1985), Icarus, 63, 317-332. (2) Bar-Nun, A., J. Dror, E. Kochavi, and D. Laufer, (1987), Physical Review B, 35, no. 5, 2427-2435. (3) Hudson, R. L., and B. Donn, (1991), Icarus, 94, 326-332. (4) Sandford, S. A., L. J. Allamandola, A. G. G. M. Tielens, and G. J. Valero, (1988), Astrophysical Journal, 329, 498-510.
NASA Technical Reports Server (NTRS)
Stokely, C.; Stansbery, E.
2006-01-01
Data from the MIT Lincoln Laboratory (MIT/LL) Long Range Imaging Radar (known as the Haystack radar) have been used in the past to examine families of objects from individual satellite breakups or families of orbiting objects that can be isolated in altitude and inclination. This is possible because for some time after a breakup, the debris cloud of particles can remain grouped together in similar orbit planes. This cloud will be visible to the radar, in fixed staring mode, for a short time twice each day, as the orbit plane moves through the field of view. There should be a unique three-dimensional pattern in observation time, range, and range rate which can identify the cloud. Eventually, through slightly differing precession rates of the right ascension of ascending node of the debris cloud, the observation time becomes distributed so that event identification becomes much more difficult. Analyses of the patterns in observation time, range, and range rate have identified good debris candidates released from the polar orbiting SNAPSHOT satellite (International Identifier: 1965-027A). For orbits near 90o inclination, there is essentially no precession of the orbit plane. The SNAPSHOT satellite is a well known nuclear powered satellite launched in 1965 to a near circular 1300 km orbit with an inclination of 90.3o. This satellite began releasing debris in 1979 with new pieces being discovered and cataloged over the years. 51 objects are still being tracked by the United States Space Surveillance Network. An analysis of the Haystack data has identified at least 60 pieces of debris separate from the 51 known tracked debris pieces, where all but 2 of the 60 pieces have a size less than 10cm. The altitude and inclination (derived from range-rate with a circular orbit assumption) are consistent with the SNAPSHOT satellite and its tracked debris cloud.
Haya, Nir; Baessler, Kaven; Christmann-Schmid, Corina; de Tayrac, Renaud; Dietz, Viviane; Guldberg, Rikke; Mascarenhas, Teresa; Nussler, Emil; Ballard, Emma; Ankardal, Maud; Boudemaghe, Thierry; Wu, Jennifer M; Maher, Christopher F
2015-06-01
The purpose of this study was to report the rates and types of pelvic organ prolapse (POP) and female continence surgery performed in member countries of the Organization for Economic Co-operation and Development (OECD) in 2012. The published health outcome data sources of the 34 OECD countries were contacted for data on POP and female continence interventions from 2010-2012. In nonresponding countries, data were sought from national or insurer databases. Extracted data were entered into an age-specific International Classification of Disease, edition 10 (ICD-10)-compliant Excel spreadsheet by 2 authors independently in English-speaking countries and a single author in non-English-speaking countries. Data were collated centrally and discrepancies were resolved by mutual agreement. We report on 684,250 POP and 410,352 continence procedures that were performed in 15 OECD countries in 2012. POP procedures (median rate, 1.38/1000 women; range, 0.51-2.55 prolapse procedures/1000 women) were performed 1.8 times more frequently than continence procedures (median rate, 0.75/1000 women; range, 0.46-1.65 continence procedures/1000 women). Repairs of the anterior vaginal compartment represented 54% of POP procedures; posterior repairs represented 43% of the procedures, and apical compartment repairs represented 20% of POP procedures. Median rate of graft usage was 15.7% of anterior vaginal repairs (range, 3.3-25.6%) and 8.5% (range, 3.2-17%) of posterior vaginal repairs. Apical compartment repairs were repaired vaginally at a median rate of 70% (range, 35-95%). Sacral colpopexy represented a median rate of 17% (range, 5-65%) of apical repairs; 61% of sacral colpopexies were performed minimally invasively. Between 2010 and 2012, there was a 3.7% median reduction in transvaginal grafts, a 4.0% reduction in midurethral slings, and a 25% increase in sacral colpopexies that were performed per 1000 women. Midurethral slings represented 82% of female continence surgeries. The 5-fold variation in the rate of prolapse interventions within OECD countries needs further evaluation. The significant heterogeneity (>10 times) in the rates at which individual POP procedures are performed indicates a lack of uniformity in the delivery of care to women with POP and demands the development of uniform guidelines for the surgical management of prolapse. In contrast, the midurethral slings were the standard female continence surgery performed throughout OECD countries in 2012. Copyright © 2015 Elsevier Inc. All rights reserved.
2016-08-19
From 2007 to 2015, the birth rate for female teens aged 15-19 years declined 46%, from 41.5 to 22.3 births per 1,000, the lowest rate ever recorded for this population in the United States. In 2015, rates declined to record lows for all racial/ethnic populations, with declines ranging from 41% for non-Hispanic white teens to 54% for Hispanic teens. Despite the declines, teen birth rates by race/Hispanic ethnicity continued to reflect wide disparities, with rates ranging from 6.9 per 1,000 for Asian or Pacific Islander teens to 34.9 for Hispanic teens in 2015.
Retrospective Evaluation of the Effect of Heart Rate on Survival in Dogs with Atrial Fibrillation.
Pedro, B; Dukes-McEwan, J; Oyama, M A; Kraus, M S; Gelzer, A R
2018-01-01
Atrial fibrillation (AF) usually is associated with a rapid ventricular rate. The optimal heart rate (HR) during AF is unknown. Heart rate affects survival in dogs with chronic AF. Forty-six dogs with AF and 24-hour ambulatory recordings were evaluated. Retrospective study. Holter-derived HR variables were analyzed as follows: mean HR (meanHR, 24-hour average), minimum HR (minHR, 1-minute average), maximum HR (maxHR, 1-minute average). Survival times were recorded from the time of presumed adequate rate control. The primary endpoint was all-cause mortality. Cox proportional hazards analysis identified variables independently associated with survival; Kaplan-Meier survival analysis estimated the median survival time of dogs with meanHR <125 bpm versus ≥125 bpm. All 46 dogs had structural heart disease; 31 of 46 had congestive heart failure (CHF), 44 of 46 received antiarrhythmic drugs. Of 15 dogs with cardiac death, 14 had CHF. Median time to all-cause death was 524 days (Interquartile range (IQR), 76-1,037 days). MeanHR was 125 bpm (range, 62-203 bpm), minHR was 82 bpm (range, 37-163 bpm), maxHR was 217 bpm (range, 126-307 bpm). These were significantly correlated with all-cause and cardiac-related mortality. For every 10 bpm increase in meanHR, the risk of all-cause mortality increased by 35% (hazard ratio, 1.35; 95% CI, 1.17-1.55; P < 0.001). Median survival time of dogs with meanHR<125 bpm (n = 23) was significantly longer (1,037 days; range, 524-open) than meanHR ≥125 bpm (n = 23; 105 days; range, 67-267 days; P = 0.0012). Mean HR was independently associated with all-cause and cardiovascular mortality (P < 0.003). Holter-derived meanHR affects survival in dogs with AF. Dogs with meanHR <125 bpm lived longer than those with meanHR ≥ 125 bpm. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Gaffney, Shannon; Moody, Emily; McKinley, Meg; Knutsen, Jeffrey; Madl, Amy; Paustenbach, Dennis
2008-05-01
An exposure simulation was conducted to characterize methanol exposure of workers who cleaned wafers in quality control departments within the semiconductor industry. Short-term (15 min) and long-term (2-4 hr) personal and area samples (at distances of 1 m and 3-6 m from the source) were collected during the 2-day simulation. On the first day, 45 mL of methanol were used per hour by a single worker washing wafers in a 102 m(3) room with a ventilation rate of about 10 air changes per hour (ACH). Virtually all methanol volatilized. To assess exposures under conditions associated with higher productivity, on the second day, two workers cleaned wafers simultaneously, together using methanol at over twice the rate of the first day (95 mL/hr). On this day, the ventilation rate was halved (5 ACH). Personal concentrations on the first day averaged 60 ppm (SD = 46 ppm) and ranged from 10-140 ppm. On the second day, personal concentrations for both workers averaged 118 ppm (SD = 50 ppm; range: 64-270 ppm). Area concentrations measured on the first day at 1 m from the source and throughout the balance of the room averaged 29 ppm (SD = 19 ppm; range: 4-83 ppm) and 18 ppm (SD = 12 ppm; range: 3-42 ppm), respectively. As expected, area concentrations measured on the second day were higher than the first and averaged 73 ppm (SD = 25 ppm; range: 27-140 ppm) at 1 meter and 48 ppm (SD = 13 ppm; range: 21-67 ppm) throughout the balance of the room. The results of this simulation suggest that the use of methanol to clean semiconductor wafers without the use of local exhaust ventilation and with relatively low room ventilation rates is unlikely to result in worker exposures exceeding the current ACGIH(R) threshold limit value of 200 ppm. This study also confirmed prior studies suggesting that when a relatively volatile chemical is located within arm's length (near field), breathing zone concentrations will be about two- to threefold greater than the room concentration when the air exchange rate is 5-10 ACH.
Thompson, Sally E; Levin, Simon; Rodriguez-Iturbe, Ignacio
2014-04-01
Global change will simultaneously impact many aspects of climate, with the potential to exacerbate the risks posed by plant pathogens to agriculture and the natural environment; yet, most studies that explore climate impacts on plant pathogen ranges consider individual climatic factors separately. In this study, we adopt a stochastic modeling approach to address multiple pathways by which climate can constrain the range of the generalist plant pathogen Phytophthora cinnamomi (Pc): through changing winter soil temperatures affecting pathogen survival; spring soil temperatures and thus pathogen metabolic rates; and changing spring soil moisture conditions and thus pathogen growth rates through host root systems. We apply this model to the southwestern USA for contemporary and plausible future climate scenarios and evaluate the changes in the potential range of Pc. The results indicate that the plausible range of this pathogen in the southwestern USA extends over approximately 200,000 km(2) under contemporary conditions. While warming temperatures as projected by the IPCC A2 and B1 emissions scenarios greatly expand the range over which the pathogen can survive winter, projected reductions in spring rainfall reduce its feasible habitat, leading to spatially complex patterns of changing risk. The study demonstrates that temperature and rainfall changes associated with possible climate futures in the southwestern USA have confounding impacts on the range of Pc, suggesting that projections of future pathogen dynamics and ranges should account for multiple pathways of climate-pathogen interaction. © 2014 John Wiley & Sons Ltd.
2014-09-25
Unemployment rates in Yuma County have been historically high due to seasonal employment within the agriculture sector . In 2000, the San Lucy District of the...loader and where trees along the banks of the washes can be avoided. The source sites are highly ephemeral washes that are normally dry and flow only... Sector General Permit for the proposed sand and gravel operations. Water Resources Environmental Consequences: Effects on water resources are mostly
Future capabilities for the Deep Space Network
NASA Technical Reports Server (NTRS)
Berner, J. B.; Bryant, S. H.; Andrews, K. S.
2004-01-01
This paper will look at three new capabilities that are in different stages of development. First, turbo decoding, which provides improved telemetry performance for data rates up to about 1 Mbps, will be discussed. Next, pseudo-noise ranging will be presented. Pseudo-noise ranging has several advantages over the current sequential ranging, anmely easier operations, improved performance, and the capability to be used in a regenerative implementation on a spacecraft. Finally, Low Density Parity Check decoding will be discussed. LDPC codes can provide performance that matches or slightly exceed turbo codes, but are designed for use in the 10 Mbps range.
NASA Technical Reports Server (NTRS)
Gratz, Andrew J.; Bird, Peter
1993-01-01
The range of the measured quartz dissolution rates, as a function of temperature and pOH, extent of saturation, and ionic strength, is extended to cover a wider range of solution chemistries, using the negative crystal methodology of Gratz et al. (1990) to measure the dissolution rate. A simple rate law describing the quartz dissolution kinetics above the point of zero charge of quartz is derived for ionic strengths above 0.003 m. Measurements were performed on some defective crystals, and the mathematics of step motion was developed for quartz dissolution and was compared with rough-face behavior using two different models.
Enabling fast charging - Vehicle considerations
NASA Astrophysics Data System (ADS)
Meintz, Andrew; Zhang, Jiucai; Vijayagopal, Ram; Kreutzer, Cory; Ahmed, Shabbir; Bloom, Ira; Burnham, Andrew; Carlson, Richard B.; Dias, Fernando; Dufek, Eric J.; Francfort, James; Hardy, Keith; Jansen, Andrew N.; Keyser, Matthew; Markel, Anthony; Michelbacher, Christopher; Mohanpurkar, Manish; Pesaran, Ahmad; Scoffield, Don; Shirk, Matthew; Stephens, Thomas; Tanim, Tanvir
2017-11-01
To achieve a successful increase in the plug-in battery electric vehicle (BEV) market, it is anticipated that a significant improvement in battery performance is required to increase the range that BEVs can travel and the rate at which they can be recharged. While the range that BEVs can travel on a single recharge is improving, the recharge rate is still much slower than the refueling rate of conventional internal combustion engine vehicles. To achieve comparable recharge times, we explore the vehicle considerations of charge rates of at least 400 kW. Faster recharge is expected to significantly mitigate the perceived deficiencies for long-distance transportation, to provide alternative charging in densely populated areas where overnight charging at home may not be possible, and to reduce range anxiety for travel within a city when unplanned charging may be required. This substantial increase in charging rate is expected to create technical issues in the design of the battery system and the vehicle's electrical architecture that must be resolved. This work focuses on vehicle system design and total recharge time to meet the goals of implementing improved charge rates and the impacts of these expected increases on system voltage and vehicle components.
Hospital Variation in Time to Epinephrine for Non-Shockable In-Hospital Cardiac Arrest
Khera, Rohan; Chan, Paul S.; Donnino, Michael; Girotra, Saket
2016-01-01
Background For patients with in-hospital cardiac arrests due to non-shockable rhythms, delays in epinephrine administration beyond 5 minutes is associated with worse survival. However, the extent of hospital variation in delayed epinephrine administration and its impact on hospital-level outcomes is unknown. Methods Within Get with the Guidelines-Resuscitation, we identified 103,932 adult patients (≥18 years) at 548 hospitals with an in-hospital cardiac arrest due to a non-shockable rhythm who received at least 1 dose of epinephrine between 2000 to 2014. We constructed two-level hierarchical regression models to quantify hospital variation in rates of delayed epinephrine administration (>5 minutes) and its association with hospital rates of survival to discharge and survival with functional recovery. Results Overall, 13,213 (12.7%) patients had delays to epinephrine, and this rate varied markedly across hospitals (range: 0% to 53.8%). The odds of delay in epinephrine administration were 58% higher at one randomly selected hospital compared to a similar patient at another randomly selected hospitals (median odds ratio [OR] 1.58; 95% C.I. 1.51 – 1.64). Median risk-standardized survival rate was 12.0% (range: 5.4% to 31.9%) and risk-standardized survival with functional recovery was 7.4% (range: 0.9% to 30.8%). There was an inverse correlation between a hospital’s rate of delayed epinephrine administration and its risk-standardized rate of survival to discharge (ρ= −0.22, P<0.0001) and survival with functional recovery (ρ= −0.14, P=0.001). Compared to a median survival rate of 12.9% (interquartile range 11.1% to 15.4%) at hospitals in the lowest quartile of epinephrine delay, risk-standardized survival was 16% lower at hospitals in the quartile with the highest rate of epinephrine delays (10.8%, interquartile range: 9.7% to 12.7%). Conclusions Delays in epinephrine administration following in-hospital cardiac arrest are common and varies across hospitals. Hospitals with high rates of delayed epinephrine administration had lower rates of overall survival for in-hospital cardiac arrest due to non-shockable rhythm. Further studies are needed to determine if improving hospital performance on time to epinephrine administration, especially at hospitals with poor performance on this metric will lead to improved outcomes. PMID:27908910
Hospital Variation in Time to Epinephrine for Nonshockable In-Hospital Cardiac Arrest.
Khera, Rohan; Chan, Paul S; Donnino, Michael; Girotra, Saket
2016-12-20
For patients with in-hospital cardiac arrests attributable to nonshockable rhythms, delays in epinephrine administration beyond 5 minutes is associated with worse survival. However, the extent of hospital variation in delayed epinephrine administration and its effect on hospital-level outcomes is unknown. Within Get With The Guidelines-Resuscitation, we identified 103 932 adult patients (≥18 years) at 548 hospitals with an in-hospital cardiac arrest attributable to a nonshockable rhythm who received at least 1 dose of epinephrine between 2000 and 2014. We constructed 2-level hierarchical regression models to quantify hospital variation in rates of delayed epinephrine administration (>5 minutes) and its association with hospital rates of survival to discharge and survival with functional recovery. Overall, 13 213 (12.7%) patients had delays to epinephrine, and this rate varied markedly across hospitals (range, 0%-53.8%). The odds of delay in epinephrine administration were 58% higher at 1 randomly selected hospital in comparison with a similar patient at another randomly selected hospital (median odds ratio, 1.58; 95% confidence interval, 1.51-1.64). The median risk-standardized survival rate was 12.0% (range, 5.4%-31.9%), and the risk-standardized survival with functional recovery was 7.4% (range, 0.9%-30.8%). There was an inverse correlation between a hospital's rate of delayed epinephrine administration and its risk-standardized rate of survival to discharge (ρ=-0.22, P<0.0001) and survival with functional recovery (ρ=-0.14, P=0.001). In comparison with a median survival rate of 12.9% (interquartile range, 11.1%-15.4%) at hospitals in the lowest quartile of epinephrine delay, risk-standardized survival was 16% lower at hospitals in the quartile with the highest rate of epinephrine delays (10.8%; interquartile range, 9.7%-12.7%). Delays in epinephrine administration following in-hospital cardiac arrest are common and variy across hospitals. Hospitals with high rates of delayed epinephrine administration had lower rates of overall survival for in-hospital cardiac arrest attributable to nonshockable rhythm. Further studies are needed to determine whether improving hospital performance on time to epinephrine administration, especially at hospitals with poor performance on this metric, will lead to improved outcomes. © 2016 American Heart Association, Inc.
Kotsuma, Tadayuki; Yamazaki, Hideya; Masui, Koji; Yoshida, Ken; Shimizutani, Kimishige; Akiyama, Hironori; Murakami, Shumei; Isohashi, Fumiaki; Yoshioka, Yasuo; Ogawa, Kazuhiko; Tanaka, Eiichi
2017-12-01
To examine the effectiveness of newly-installed high-dose-rate interstitial brachytherapy (HDR-ISBT) for buccal cancer. We retrospectively reviewed 36 patients (25 men and 11 women) with buccal cancer treated with curative brachytherapy with or without external radiotherapy with a median follow-up of 99 months. A total of 15 HDR-ISBT (median 48 Gy/ 8 fractions, range=24-60 Gy) patients were compared to conventional 15 cases LDR-ISBT (70 Gy, range=42.8-110 Gy) and 7 molds techniques (15 Gy, range=9-74 Gy). A total of 31 patients also underwent external radiotherapy (30 Gy, range=24-48 Gy). They comprised of 3T1, 23 T2, 8 T3, 3 T4 including 11 node positive cases. HDR-ISBT provided 82% of local control rate at 5 years, whereas conventional brachytherapy showed 72% [p=0.44; LDR-ISBT (65%), mold therapy (85.7%)]. Patients with early lesions (T1-2 or stage I-II) showed better local control rates than those with advanced lesions (T3-4 or stage III-IV). Severe late grade 3 complications developed in two patients treated with LDR-ISBT and EBRT. There is no significant difference in toxicity grade ≤2 between conventional brachytherapy (5/15=33%) and HDR-ISBT (7/32=32%, p=0.92). HDR-ISBT achieved good and comparable local control rates to conventional brachytherapy without elevating the toxicity. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Stopping of 200-GeV gold nuclei in nuclear emulsions
NASA Technical Reports Server (NTRS)
Waddington, C.J.; Freier, P. S.; Fixsen, D. J.
1983-01-01
The residual ranges of Au-197(79) nuclei stopping in nuclear emulsions has been measured for nuclei with an incident energy of 991 MeV/amu. The mean ranges observed are appreciably less than those predicted from measurements made on energetic particles of lower charge. However, by the consideration of higher-order correction terms to the rate of energy loss, good agreement can be obtained between the predicted and observed ranges.
Plasma concentrations of fentanyl with subcutaneous infusion in palliative care patients.
Miller, R S; Peterson, G M; Abbott, F; Maddocks, I; Parker, D; McLean, S
1995-12-01
1. Plasma concentrations of fentanyl were measured by g.c. in 20 patients (median age: 75 years and range: 54-86 years; eight females) in palliative care receiving the drug by continuous s.c. infusion (median rate: 1200 micrograms day-1 and range: 100-5000 micrograms day-1). 2. The infusion rate was significantly related to the duration of therapy (Spearman rho = 0.56, P < 0.05). The total steady-state plasma concentrations of fentanyl ranged between 0.1 and 9 ng ml-1, with a median of 1 ng ml-1. The unbound fraction of fentanyl in the plasma ranged from 17.8 to 44.4%, with a median value of 33.6%. Infusion rates and both total and unbound plasma concentrations of fentanyl were correlated (Spearman rho = 0.92, P < 0.05 in each case). Even with standardization for dosage, there was an eightfold variation in total plasma concentrations and 3.5-fold variation in unbound plasma concentrations of fentanyl. 3. There is considerable inter-patient variability in the pharmacokinetics of fentanyl with s.c. infusion in the palliative care setting, which necessitates careful titration of dosage according to individual clinical response.
Boeye, Jeroen; Travis, Justin M J; Stoks, Robby; Bonte, Dries
2013-01-01
Species can either adapt to new conditions induced by climate change or shift their range in an attempt to track optimal environmental conditions. During current range shifts, species are simultaneously confronted with a second major anthropogenic disturbance, landscape fragmentation. Using individual-based models with a shifting climate window, we examine the effect of different rates of climate change on the evolution of dispersal distances through changes in the genetically determined dispersal kernel. Our results demonstrate that the rate of climate change is positively correlated to the evolved dispersal distances although too fast climate change causes the population to crash. When faced with realistic rates of climate change, greater dispersal distances evolve than those required for the population to keep track of the climate, thereby maximizing population size. Importantly, the greater dispersal distances that evolve when climate change is more rapid, induce evolutionary rescue by facilitating the population in crossing large gaps in the landscape. This could ensure population persistence in case of range shifting in fragmented landscapes. Furthermore, we highlight problems in using invasion speed as a proxy for potential range shifting abilities under climate change. PMID:23467649
Open ankle arthrodeses via an anterior approach.
Gordon, David; Zicker, Robyn; Cullen, Nicholas; Singh, Dishan
2013-03-01
In open ankle arthrodesis, debate remains as to which surgical approach and fixation devices should be used. The purpose of this study was to identify union, complication, and patient satisfaction rates of ankle fusions performed at our institution, using the plane between extensor hallucis longus and tibialis anterior with medial tibiotalar screw internal fixation. A retrospective review was performed of all isolated primary fusions between 2005 and 2009. Eighty-two ankles were identified in 73 patients. All patient records were reviewed, and 57 patients (65 ankles) attended for clinical evaluation and scoring. Age range at surgery was 18 to 75 years (mean, 56.1 years); 8 patients were smokers. Diagnoses were trauma in 52 patients (63%), osteoarthritis in 17, rheumatoid arthritis in 7, Charcot-Marie-Tooth disease in 3, congenital talipes equinovarus in 2, and talar avascular necrosis in 1. Follow-up range was 7 months to 8.3 years (mean, 4 years). Time to union ranged from 8 to 39 weeks (mean, 13.3) with a union rate of 100%. The AOFAS range was 12 to 93 (mean, 70). Eighty percent were "very satisfied" or "satisfied." Major complication rate was 14.6%: 7 malalignments; 3 wound problems; 2 complex regional pain syndrome; and 2 delayed unions, both smokers. An excellent union rate, high patient satisfaction, and low complication rate were achieved with this technique. Varus malalignment and persistent pain resulted in dissatisfaction. Many patients remained highly active, and bilaterally fused patients functioned as well as unilateral ones. Level IV, retrospective case series.
Bioremediation potential of microorganisms derived from petroleum reservoirs.
Dellagnezze, Bruna Martins; de Sousa, Gabriel Vasconcelos; Martins, Laercio Lopes; Domingos, Daniela Ferreira; Limache, Elmer E G; de Vasconcellos, Suzan Pantaroto; da Cruz, Georgiana Feitosa; de Oliveira, Valéria Maia
2014-12-15
Bacterial strains and metagenomic clones, both obtained from petroleum reservoirs, were evaluated for petroleum degradation abilities either individually or in pools using seawater microcosms for 21 days. Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses were carried out to evaluate crude oil degradation. The results showed that metagenomic clones 1A and 2B were able to biodegrade n-alkanes (C14 to C33) and isoprenoids (phytane and pristane), with rates ranging from 31% to 47%, respectively. The bacteria Dietzia maris CBMAI 705 and Micrococcus sp. CBMAI 636 showed higher rates reaching 99% after 21 days. The metagenomic clone pool biodegraded these compounds at rates ranging from 11% to 45%. Regarding aromatic compound biodegradation, metagenomic clones 2B and 10A were able to biodegrade up to 94% of phenanthrene and methylphenanthrenes (3-MP, 2-MP, 9-MP and 1-MP) with rates ranging from 55% to 70% after 21 days, while the bacteria Dietzia maris CBMAI 705 and Micrococcus sp. CBMAI 636 were able to biodegrade 63% and up to 99% of phenanthrene, respectively, and methylphenanthrenes (3-MP, 2-MP, 9-MP and 1-MP) with rates ranging from 23% to 99% after 21 days. In this work, isolated strains as well as metagenomic clones were capable of degrading several petroleum compounds, revealing an innovative strategy and a great potential for further biotechnological and bioremediation applications. Copyright © 2014 Elsevier Ltd. All rights reserved.
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.
Evolution of density-dependent movement during experimental range expansions.
Fronhofer, E A; Gut, S; Altermatt, F
2017-12-01
Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.
323 N. Michigan Ave, March 2016, Lindsay Light Radiological Survey
The count rates in the excavation ranged from 2,100 cpm to3,300 cpm. There was a layer of granite pavers immediately below the surfacecontaining Naturally Occurring Radioactive Material (NORM) that ranged from 5,500cpm to 8,400 cpm.
Kellam, Patrick; Ostrum, Robert F
2016-01-01
To determine the incidence rate and associative factors for the development of avascular necrosis (AVN) and posttraumatic arthritis (PTA) after traumatic hip dislocation and time to reduction. A comprehensive search of databases including PubMed, Cochrane Database, and Embase through April 2014 for English articles reporting complications of AVN and PTA after hip dislocation was performed. Inclusion criteria were English-only studies, a patient population of adults, study outcomes of AVN and/or PTA reported, and articles reported at least type I dislocations. Two authors independently extracted data from the selected studies and the data collected were compared to verify agreement. Random-effects models were used for meta-analysis. The overall event rate of AVN and PTA was calculated and stratified based on Thompson-Epstein of the hip dislocation. Odds ratios were calculated for those articles that reported rates of AVN based on time to reduction. For anterior dislocations, the event rate for AVN ranged from 0.087 to 0.333, whereas the event rate for PTA ranged from 0.125 to 0.700. Analysis of posterior dislocations revealed that the event rate for AVN ranged from 0.106 to 0.430; additionally, the event rate for PTA ranged from 0.194 to 0.586. For posterior hip dislocations and type I and II anterior dislocations, the severity of the injury correlates with an increase in the development of AVN and PTA. The odds ratio of AVN for those hip dislocations reduced after 12 hours versus those reduced before 12 hours was 5.627. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
The Rate of Binary Black Hole Mergers Inferred from Advanced LIGO Observations Surrounding GW150914
NASA Astrophysics Data System (ADS)
Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Behnke, B.; Bejger, M.; Bell, A. S.; Bell, C. J.; Berger, B. K.; Bergman, J.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birney, R.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bohe, A.; Bojtos, P.; Bond, C.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brown, N. M.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, H. Y.; Chen, Y.; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, S.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M., Jr.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dattilo, V.; Dave, I.; Daveloza, H. P.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; De, S.; DeBra, D.; Debreczeni, G.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dojcinoski, G.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etzel, T.; Evans, M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M.; Fong, H.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gatto, A.; Gaur, G.; Gehrels, N.; Gemme, G.; Gendre, B.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gordon, N. A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Hall, B. R.; Hall, E. D.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Hofman, D.; Hollitt, S. E.; Holt, K.; Holz, D. E.; Hopkins, P.; Hosken, D. J.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Idrisy, A.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J.-M.; Isi, M.; Islas, G.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jiménez-Forteza, F.; Johnson, W. W.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; K, Haris; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Karki, S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kawazoe, F.; Kéfélian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.; Key, J. S.; Khalaidovski, A.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, C.; Kim, J.; Kim, K.; Kim, Nam-Gyu; Kim, Namjun; Kim, Y.-M.; King, E. J.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Kokeyama, K.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Krishnan, B.; Królak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Levine, B. M.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Logue, J.; Lombardi, A. L.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lück, H.; Lundgren, A. P.; Luo, J.; Lynch, R.; Ma, Y.; MacDonald, T.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Magee, R. M.; Mageswaran, M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandel, I.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martin, R. M.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B. C.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P. G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Necula, V.; Nedkova, K.; Nelemans, G.; Neri, M.; Neunzert, A.; Newton, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perreca, A.; Phelps, M.; Piccinni, O.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poggiani, R.; Popolizio, P.; Porter, E. K.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Premachandra, S. S.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Ricci, F.; Riles, K.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sampson, L.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Serna, G.; Setyawati, Y.; Sevigny, A.; Shaddock, D. A.; Shah, S.; Shahriar, M. S.; Shaltev, M.; Shao, Z.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sigg, D.; Silva, A. D.; Simakov, D.; Singer, A.; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, J. R.; Smith, N. D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson, S.; Stone, R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tápai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Tomlinson, C.; Tonelli, M.; Torres, C. V.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifirò, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Welborn, T.; Wen, L.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; White, D. J.; Whiting, B. F.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Worden, J.; Wright, J. L.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, H.; Yvert, M.; Zadrożny, A.; Zangrando, L.; Zanolin, M.; Zendri, J.-P.; Zevin, M.; Zhang, F.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.; Zweizig, J.; LIGO Scientific Collaboration; Virgo Collaboration
2016-12-01
A transient gravitational-wave signal, GW150914, was identified in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To assess the implications of this discovery, the detectors remained in operation with unchanged configurations over a period of 39 days around the time of the signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous two-detector observational data is estimated to have a false-alarm rate (FAR) of \\lt 4.9× {10}-6 {{yr}}-1, yielding a p-value for GW150914 of \\lt 2× {10}-7. Parameter estimation follow-up on this trigger identifies its source as a binary black hole (BBH) merger with component masses ({m}1,{m}2)=({36}-4+5,{29}-4+4) {M}⊙ at redshift z={0.09}-0.04+0.03 (median and 90% credible range). Here, we report on the constraints these observations place on the rate of BBH coalescences. Considering only GW150914, assuming that all BBHs in the universe have the same masses and spins as this event, imposing a search FAR threshold of 1 per 100 years, and assuming that the BBH merger rate is constant in the comoving frame, we infer a 90% credible range of merger rates between 2{--}53 {{Gpc}}-3 {{yr}}-1 (comoving frame). Incorporating all search triggers that pass a much lower threshold while accounting for the uncertainty in the astrophysical origin of each trigger, we estimate a higher rate, ranging from 13{--}600 {{Gpc}}-3 {{yr}}-1 depending on assumptions about the BBH mass distribution. All together, our various rate estimates fall in the conservative range 2{--}600 {{Gpc}}-3 {{yr}}-1.
Late Quaternary denudation, Death and Panamint Valleys, eastern California
Jayko, A.S.
2005-01-01
Late Quaternary denudation rates are constrained from alluvial fans and tributary watersheds in central Death and Panamint Valleys. Preliminary results suggest that the denudation rate is in part a function of the mean watershed elevation. Rainfall increases semi-logarithmically with higher elevation to about 2500 m where it becomes limited by the regional average maximum moisture content of the air mass. The fan volumes show a power-law relation to the watershed areas. The fan volumes ranged from about 250,000 to 4000 km3 and the watershed areas range from about 60,000 to 2000 km2. The upper limit of the denudation rates estimated from small Death Valley fans restricted to the east side of the basin along the Black Mountain frontal scarp range between about 0.03 to 0.18 mm/yr. The maximum is made by assuming most of the clastic accumulation in these fans followed the last highstand of Lake Manly around 24,000 yr which is the least conservative condition. The upper limit of the denudation rates from the Panamint fans range from 0.04 to 0.20 mm/yr assuming the accumulation mainly postdates OIS-4 ???60,000 yr or OIS-2 ???20,000 yr based on the presence or absence of inset shorelines from the last glacial-pluvial maximum. The greater denudation rate associated with the higher mean watershed elevations can mainly be attributed to the greater rainfall at higher elevation. Denudation rates are about a third or less of the Neogene dip-slip rates reported from nearby active faults consistent with relief increasing during dryer periods. ?? 2005 Elsevier B.V. All rights reserved.
Compression performance of HEVC and its format range and screen content coding extensions
NASA Astrophysics Data System (ADS)
Li, Bin; Xu, Jizheng; Sullivan, Gary J.
2015-09-01
This paper presents a comparison-based test of the objective compression performance of the High Efficiency Video Coding (HEVC) standard, its format range extensions (RExt), and its draft screen content coding extensions (SCC). The current dominant standard, H.264/MPEG-4 AVC, is used as an anchor reference in the comparison. The conditions used for the comparison tests were designed to reflect relevant application scenarios and to enable a fair comparison to the maximum extent feasible - i.e., using comparable quantization settings, reference frame buffering, intra refresh periods, rate-distortion optimization decision processing, etc. It is noted that such PSNR-based objective comparisons generally provide more conservative estimates of HEVC benefit than are found in subjective studies. The experimental results show that, when compared with H.264/MPEG-4 AVC, HEVC version 1 provides a bit rate savings for equal PSNR of about 23% for all-intra coding, 34% for random access coding, and 38% for low-delay coding. This is consistent with prior studies and the general characterization that HEVC can provide about a bit rate savings of about 50% for equal subjective quality for most applications. The HEVC format range extensions provide a similar bit rate savings of about 13-25% for all-intra coding, 28-33% for random access coding, and 32-38% for low-delay coding at different bit rate ranges. For lossy coding of screen content, the HEVC screen content coding extensions achieve a bit rate savings of about 66%, 63%, and 61% for all-intra coding, random access coding, and low-delay coding, respectively. For lossless coding, the corresponding bit rate savings are about 40%, 33%, and 32%, respectively.
GPS Imaging of Sierra Nevada Uplift
NASA Astrophysics Data System (ADS)
Hammond, W. C.; Blewitt, G.; Kreemer, C.
2015-12-01
Recent improvements in the scope and precision of GPS networks across California and Nevada have allowed for uplift of the Sierra Nevada to be observed directly. Much of the signal, in the range of 1 to 2 mm/yr, has been attributed to lithospheric scale rebound following massive groundwater withdrawal in the San Joaquin Valley in southern California, exacerbated by drought since 2011. However, natural tectonic deformation associated with long term uplift of the range may also contribute to the observed signal. We have developed new algorithms that enhance the signal of Sierra Nevada uplift and improve our ability to interpret and separate natural tectonic signals from anthropogenic contributions. We apply our new Median Interannual Difference Adjusted for Skewness (MIDAS) algorithm to the vertical times series and a inverse distance-weighted median spatial filtering and Delaunay-based interpolation to despeckle the rate map. The resulting spatially continuous vertical rate field is insensitive to outliers and steps in the GPS time series, and omits isolated features attributable to unstable stations or unrepresentative rates. The resulting vertical rate field for California and Nevada exhibits regionally coherent signals from the earthquake cycle including interseismic strain accumulation in Cascadia, postseismic relaxation of the mantle from recent large earthquakes in central Nevada and southern California, groundwater loading changes, and tectonic uplift of the Sierra Nevada and Coast Ranges. Uplift of the Sierra Nevada extends from the Garlock Fault in the south to an indefinite boundary in the north near the latitude of Mt. Lassen to the eastern Sierra Nevada range front in Owen's Valley. The rates transition to near zero in the southern Walker Lane. The eastern boundary of uplift coincides with the highest strain rates in the western Great Basin, suggesting higher normal fault slip rates and a component of tectonic uplift of the Sierra Nevada.
Analysis of possible future atmospheric retention of fossil fuel CO/sub 2/
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edmonds, J.A.; Reilly, J.; Trabalka, J.R.
1984-09-01
This report investigates the likely rates and the potential range of future CO/sub 2/ emissions, combined with knowledge of the global cycle of carbon, to estimate a possible range of future atmospheric CO/sub 2/ concentrations through the year 2075. Historic fossil fuel usage to the present, growing at a rate of 4.5% per year until 1973 and at a slower rate of 1.9% after 1973, was combined with three scenarios of projected emissions growth ranging from approximately 0.2 to 2.8% per year to provide annual CO/sub 2/ emissions data for two different carbon cycle models. The emissions scenarios were constructedmore » using an energy-economic model and by varying key parameters within the bounds of currently expected future values. The extreme values for CO/sub 2/ emissions in the year 2075 are 6.8 x 10/sup 15/ and 91 x 10/sup 15/ g C year/sup -1/. Carbon cycle model simulations used a range of year - 1800 preindustrial atmospheric concentrations of 245 to 292 ppM CO/sub 2/ and three scenarios of bioshere conversion as additional atmospheric CO/sub 2/ source terms. These simulations yield a range of possible atmospheric CO/sub 2/ concentrations in year 2075 of approximately 500 to 1500 ppM, with a median of about 700 ppM. The time at which atmospheric CO/sub 2/ would potentially double from the preindustrial level ranges from year 2025 to >2075. The practical, programmatic value of this forecast exercise is that it forces quantitative definition of the assumptions, and the uncertainties therein, which form the basis of our understanding of the natural biogeochemical cycle of carbon and both historic and future human influences on the dynamics of the global cycle. Assumptions about the possible range of future atmospheric CO/sub 2/ levels provide a basis on which to evaluate the implications of these changes on climate and the biosphere. 44 references, 17 figures, 21 tables.« less
Advanced digital SAR processing study
NASA Technical Reports Server (NTRS)
Martinson, L. W.; Gaffney, B. P.; Liu, B.; Perry, R. P.; Ruvin, A.
1982-01-01
A highly programmable, land based, real time synthetic aperture radar (SAR) processor requiring a processed pixel rate of 2.75 MHz or more in a four look system was designed. Variations in range and azimuth compression, number of looks, range swath, range migration and SR mode were specified. Alternative range and azimuth processing algorithms were examined in conjunction with projected integrated circuit, digital architecture, and software technologies. The advaced digital SAR processor (ADSP) employs an FFT convolver algorithm for both range and azimuth processing in a parallel architecture configuration. Algorithm performace comparisons, design system design, implementation tradeoffs and the results of a supporting survey of integrated circuit and digital architecture technologies are reported. Cost tradeoffs and projections with alternate implementation plans are presented.
Kang, Seol-Jung; Ha, Gi-Chul; Ko, Kwang-Jun
2017-06-01
The present study aimed to investigate the association between metabolic syndrome and cardiorespiratory fitness according to resting heart rate of Korean male adults. A total of 11,876 male adults aged 20-65 years who underwent health examinations from 2010 to 2015 at a National Fitness Centre in South Korea were included. Subjects' resting heart rate, cardiorespiratory fitness (VO 2 max), and metabolic syndrome parameters were collected. The subjects were divided into 5 categories (<60 bpm, 60-69 bpm, 70-79 bpm, 80-89 bpm, and ≥90 bpm) of resting heart rate for further analysis. We found that elevated resting heart rate was positively associated with body mass index, systolic blood pressure, diastolic blood pressure, triglycerides, and fasting blood glucose levels ( p < 0.001, respectively); in contrast, elevated resting heart rate was inversely associated with VO 2 max ( p < 0.001). When resting heart rate of subjects was categorized into quintiles and analysed, the results showed that the relative risk of metabolic syndrome was 1.53-fold higher (95% CI, 1.34 to 1.82) in the range of 60-69 beats per minute (bpm), 2.08-fold higher (95% CI, 1.77 to 2.45) in the range of 70-79 bpm, 2.28-fold higher (95% CI, 1.73 to 3.00) in the range of 80-89 bpm, and 2.61-fold higher (95% CI, 1.62 to 4.20) in the range of ≥90 bpm, compared to those <60 bpm; this indicated that as resting heart rate increased, the relative risk of metabolic syndrome also increased. Resting heart rate of male adults was found to be associated with cardiorespiratory fitness; the risk factors for metabolic syndrome and relative risk of metabolic syndrome increased as resting heart rate increased.
van Oeffelen, A A M; van den Broek, I V F; Doesburg, M; Boogmans, B; Götz, H M; van Leeuwen-Voerman, F A M; van Veen, M G; Woestenberg, P J; van Benthem, B H B; van Steenbergen, J E
2017-02-01
Ethnic minorities (EM) from STI-endemic countries are at increased risk to acquire an STI. The objectives of this study were to investigate the difference in STI clinic consultation and positivity rates between ethnic groups, and compare findings between Dutch cities. Aggregated population numbers from 2011 to 2013 of 15-44 year-old citizens of Amsterdam, Rotterdam, The Hague and Utrecht extracted from the population register (N=3 129 941 person-years) were combined with aggregated STI clinic consultation data in these cities from the national STI surveillance database (N=113 536). Using negative binomial regression analyses (adjusted for age and gender), we compared STI consultation and positivity rates between ethnic groups and cities. Compared with ethnic Dutch (consultation rate: 40.3/1000 person-years), EM from Eastern Europe, Sub-Sahara Africa, Suriname, the Netherlands Antilles/Aruba and Latin America had higher consultation rates (range relative risk (RR): 1.27-2.26), whereas EM from Turkey, North Africa, Asia and Western countries had lower consultation rates (range RR: 0.29-0.82). Of the consultations among ethnic Dutch, 12.2% was STI positive. Positivity rates were higher among all EM groups (range RR: 1.14-1.81). Consultation rates were highest in Amsterdam and lowest in Utrecht independent of ethnic background (range RR Amsterdam vs Utrecht: 4.30-10.30). Positivity rates differed less between cities. There were substantial differences in STI clinic use between ethnic groups and cities in the Netherlands. Although higher positivity rates among EM suggest that these high-risk individuals reach STI clinics, it remains unknown whether their reach is optimal. Special attention should be given to EM with comparatively low consultation rates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Bradley, P.M.; Chapelle, F.H.
1998-01-01
Discharge of DCE and VC to an aerobic surface water system simultaneously represents a significant environmental concern and, potentially, a non-engineered opportunity for efficient contaminant bioremediation. The potential for bioremediation, however, depends on the ability of the stream-bed microbial community to efficiently and completely degrade DCE and VC over a range of contaminant concentrations. The purposes of the studies reported here were to assess the potential for aerobic DCE and VC mineralization by stream-bed microorganisms and to evaluate the effects of DCE and VC concentrations on the apparent rates of aerobic mineralization. Bed-sediment microorganisms indigenous to a creek, where DCE-contaminated groundwater continuously discharges, demonstrated rapid mineralization of DCE and VC under aerobic conditions. Over 8 days, the recovery of [1,2-14C]DCE radioactivity as 14CO2 ranged from 17% to 100%, and the recovery of [1,2- 14C]VC radioactivity as 14CO2 ranged from 45% to 100%. Rates of DCE and VC mineralization increased significantly with increasing contaminant concentration, and the response of apparent mineralization rates to changes in DCE and VC concentrations was adequately described by Michaelis-Menten kinetics.Discharge of DCE and VC to an aerobic surface water system simultaneously represents a significant environmental concern and, potentially, a non-engineered opportunity for efficient contaminant bioremediation. The potential for bioremediation, however, depends on the ability of the stream-bed microbial community to efficiently and completely degrade DCE and VC over a range of contaminant concentrations. The purposes of the studies reported here were to assess the potential for aerobic DCE and VC mineralization by stream-bed microorganisms and to evaluate the effects of DCE and VC concentrations on the apparent rates of aerobic mineralization. Bed-sediment microorganisms indigenous to a creek, where DCE-contaminated groundwater continuously discharges, demonstrated rapid mineralization of DCE and VC under aerobic conditions. Over 8 days, the recovery of [1,2-14C]DCE radioactivity as 14CO2 ranged from 17% to 100%, and the recovery of [1,2-14C]VC radioactivity as 14CO2 ranged from 45% to 100%. Rates of DCE and VC mineralization increased significantly with increasing contaminant concentration, and the response of apparent mineralization rates to changes in DCE and VC concentrations was adequately described by Michaelis-Menten kinetics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Colonias, Athanasios, E-mail: acolonia@wpahs.or; Drexel University College of Medicine, Allegheny Campus, Pittsburgh, PA; Betler, James
2011-01-01
Purpose: To update the Allegheny General Hospital experience of high-risk Stage I non-small-cell lung cancer patients treated with sublobar resection and intraoperative {sup 125}I Vicryl mesh brachytherapy. Methods and Materials: Between January 5, 1996 and February 19, 2008, 145 patients with Stage I non-small-cell lung cancer who were not lobectomy candidates because of cardiopulmonary compromise underwent sublobar resection and placement of {sup 125}I seeds along the resection line. The {sup 125}I seeds embedded in Vicryl suture were attached with surgical clips to a sheet of Vicryl mesh, inserted over the target area, and prescribed to a 0.5-cm planar margin. Results:more » The mean target area, total activity, number of seeds implanted, and prescribed total dose was 33.3 cm{sup 2} (range, 18.0-100.8), 20.2 mCi (range, 11.1-29.7), 46 (range, 30-100), and 117 Gy (range, 80-180), respectively. The median length of the surgical stay was 6 days (range, 1-111), with a perioperative mortality rate of 3.4%. At a median follow-up of 38.3 months (range, 1-133), 6 patients had developed local recurrence (4.1%), 9 had developed regional failure (6.2%), and 25 had distant failure (17.2%). On multivariate analysis, no patient- or tumor-specific factors or surgical or dosimetric factors were predictive of local recurrence. The overall median survival was 30.5 months with a 3- and 5-year overall survival rate of 65% and 35%, respectively. Conclusion: {sup 125}I brachytherapy for high-risk, Stage I non-small-cell lung cancer after sublobar resection is well tolerated and associated with a low local failure rate.« less
Ionospheric range-rate effects in satellite-to-satellite tracking
NASA Technical Reports Server (NTRS)
Lipofsky, J. R.; Bent, R. B.; Llewellyn, S. K.; Schmid, P. E.
1977-01-01
Investigation of ionospheric range and range-rate corrections in satellite-to-satellite tracking were investigated. Major problems were cited and the magnitude of errors that have to be considered for communications between satellites and related experiments was defined. The results point to the need of using a sophisticated modeling approach incorporating daily solar data, and where possible actual ionospheric measurements as update information, as a simple median model cannot possibly account for the complex interaction of the many variables. The findings provide a basis from which the residual errors can be estimated after ionospheric modeling is incorporated in the reduction. Simulations were performed for satellites at various heights: Apollo, Geos, and Nimbus tracked by ATS-6; and in two different geometric configurations: coplanar and perpendicular orbits.
Prentice, Carol S.; Crosby, Christopher J.; Weber, John C.; Ragona, Daniel
2010-01-01
Recent geodetic studies suggest that the Central Range fault is the principal plate-boundary structure accommodating strike-slip motion between the Caribbean and South American plates. Our study shows that the fault forms a topographically prominent lineament in central Trinidad. Results from a paleoseismic investigation at a site where Holocene sediments have been deposited across the Central Range fault indicate that it ruptured the ground surface most recently between 2710 and 550 yr B.P. If the geodetic slip rate of 9–15 mm/yr is representative of Holocene slip rates, our paleoseismic data suggest that at least 4.9 m of potential slip may have accumulated on the fault and could be released during a future large earthquake (M > 7).
Geothermal segmentation of the Cascade Range in the USA
Guffanti, Marianne; Muffler, L.J.; Mariner, R.H.; Sherrod, D.R.; Smith, James G.; Blackwell, D.D.; Weaver, C.S.
1990-01-01
Characteristics of the crustal thermal regime of the Quaternary Cascades vary systematically along the range. Spatially congruent changes in volcanic vent distribution, volcanic extrusion rate, hydrothermal discharge rate, and regional conductive heat flow define 5 geothermal segments. These segments are, from north to south: (1) the Washington Cascades north of Mount Rainier, (2) the Cascades from Mount Rainier to Mount Hood, (3) the Oregon Cascades from south of Mount Hood to the California border, (4) northernmost California, including Mount Shasta and Medicine Lake volcano, and (5) the Lassen region of northern California. This segmentation indicates that geothermal resource potential is not uniform in the Cascade Range. Potential varies from high in parts of Oregon to low in Washington north of Mount Rainier.
Slow speed—fast motion: time-lapse recordings in physics education
NASA Astrophysics Data System (ADS)
Vollmer, Michael; Möllmann, Klaus-Peter
2018-05-01
Video analysis with a 30 Hz frame rate is the standard tool in physics education. The development of affordable high-speed-cameras has extended the capabilities of the tool for much smaller time scales to the 1 ms range, using frame rates of typically up to 1000 frames s-1, allowing us to study transient physics phenomena happening too fast for the naked eye. Here we want to extend the range of phenomena which may be studied by video analysis in the opposite direction by focusing on much longer time scales ranging from minutes, hours to many days or even months. We discuss this time-lapse method, needed equipment and give a few hints of how to produce respective recordings for two specific experiments.
Reproductive performance in a select sample of dairy herds.
Ferguson, James D; Skidmore, Andrew
2013-02-01
Sixteen herds were selected from a pool of 64 herds nominated by consultants for participation in a national survey to demonstrate excellence in reproductive performance. For inclusion in the survey, herds had to have comprehensive records in a farm computer database or participate in a Dairy Herd Improvement Association record system and have superior reproductive performance as judged by the herd advisor. Herd managers were asked to fill out a questionnaire to describe their reproductive management practices and provide herd records for data analysis. Reproductive analysis was based on individual cow records for active and cull dairy cows that calved during the calendar year 2010. Breeding records by cow were used to calculate indices for insemination rate (IR), conception rate (CR), pregnancy rate (PR), and culling. Herds ranged in size from 262 to 6,126 lactating and dry cows, with a mean of 1,654 [standard deviation (SD) 1,494] cows. Mean days to first insemination (DFS) was 71.2d (SD 4.7d), and IR for first insemination was 86.9%. Mean days between inseminations were 33.4d (SD 3.1d), and 15.4% of insemination intervals were greater than 48 d (range: 7.2 to 21.5%). First-service conception rate was 44.4% (SD 4.8%) across all herds and ranged from 37.5 to 51.8%. Mean PR was 32.0% (SD 3.9%) with a range of 26.5 to 39.4%. Lactation cull rate was 32.2% (SD 12.4%) with a range from 13.6 to 58.1%. Compared with mean data and SD for herds in the Raleigh Dairy Herd Improvement Association system, mean indices for these herds ranked them in the 99 th percentile for IR (using heat detection rate as comparison), 99 th percentile for PR, the bottom 18.6 percentile for DFS, and around the 50th percentile for CR. This suggests that excellent herd reproductive performance was associated with reproductive management that resulted in high insemination rates combined with average CR. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
The range expansion patterns of Spartina alterniflora on salt marshes in the Yangtze Estuary, China
NASA Astrophysics Data System (ADS)
Xiao, Derong; Zhang, Liquan; Zhu, Zhenchang
2010-06-01
The range expansion patterns of Spartina alterniflora and the roles which sexual reproduction and asexual propagation play in range expansion were investigated at the Chongming Dongtan nature reserve in the Yangtze Estuary, China. Two range expansion patterns of S. alterniflora at its advancing fronts could be found (1) S. alterniflora-mudflat front (S-M) and (2) S. alterniflora- Scirpus mariqueter-mudflat front (S-S-M). One feature revealed by this study was that a flush of seedling recruitment and establishment in spring was a crucial way for S. alterniflora to colonize new habitats and achieve a fast rate of range expansion. The mean number of seedlings recruited at the S-M front was much higher than that at the S-S-M front. Once established, the survivorship of seedlings was high, both at the S-M and S-S-M fronts. The established seedlings formed new tussocks quickly by vegetative tillering and growth of rhizomes and these finally merged into dense meadows. The mean distance of range expansion of S. alterniflora, after one growing season at the S-M front, was 25.4 ± 3.1 m yr -1 and 2.7 ± 0.5 m yr -1 at the S-S-M front. Sexual reproduction by seedlings and asexual propagation by tillering and growth of rhizomes were the two main means by which S. alterniflora could maintain a fast rate of range expansion on the salt marshes of the Yangtze Estuary. The colonization behaviors of S. alterniflora on advancing fronts differed as a reaction to various external and internal factors. The impact of abiotic and biotic factors governing the range expansion of S. alterniflora and its implications for the spatial structure of tidal wetlands are discussed.
Revisiting Trypanosoma rangeli Transmission Involving Susceptible and Non-Susceptible Hosts
Ferreira, Luciana de Lima; Pereira, Marcos Horácio; Guarneri, Alessandra Aparecida
2015-01-01
Trypanosoma rangeli infects several triatomine and mammal species in South America. Its transmission is known to occur when a healthy insect feeds on an infected mammal or when an infected insect bites a healthy mammal. In the present study we evaluated the classic way of T. rangeli transmission started by the bite of a single infected triatomine, as well as alternative ways of circulation of this parasite among invertebrate hosts. The number of metacyclic trypomastigotes eliminated from salivary glands during a blood meal was quantified for unfed and recently fed nymphs. The quantification showed that ~50,000 parasites can be liberated during a single blood meal. The transmission of T. rangeli from mice to R. prolixus was evaluated using infections started through the bite of a single infected nymph. The mice that served as the blood source for single infected nymphs showed a high percentage of infection and efficiently transmitted the infection to new insects. Parasites were recovered by xenodiagnosis in insects fed on mice with infections that lasted approximately four months. Hemolymphagy and co-feeding were tested to evaluate insect-insect T. rangeli transmission. T. rangeli was not transmitted during hemolymphagy. However, insects that had co-fed on mice with infected conspecifics exhibited infection rates of approximately 80%. Surprisingly, 16% of the recipient nymphs became infected when pigeons were used as hosts. Our results show that T. rangeli is efficiently transmitted between the evaluated hosts. Not only are the insect-mouse-insect transmission rates high, but parasites can also be transmitted between insects while co-feeding on a living host. We show for the first time that birds can be part of the T. rangeli transmission cycle as we proved that insect-insect transmission is feasible during a co-feeding on these hosts. PMID:26469403
DeWalt, Saara J.; Zou, Jianwen; Rogers, William E.
2017-01-01
Abstract The success of invasive plants may reflect environmental differences in their native and introduced ranges including both abiotic and biotic conditions, such as release from aboveground herbivory. However, in response to these novel conditions, plants from invasive populations may have higher growth rates and lower defence levels compared with those in the native range. This may contribute to their success in the introduced range but perhaps not in the native range. Here, we grew 1000 Triadica sebifera plants from 14 native and introduced populations in seven common gardens with unmanaged background vegetation for three growing seasons in three geographic venues that varied in T. sebifera status and insect herbivore communities: Texas—T. sebifera is invasive, low levels of generalist herbivory; Hawaii—T. sebifera introduced but not invasive, high levels of generalist herbivory from exotic herbivores; China—native range, both generalist and specialist herbivores. We suppressed aboveground insects with insecticide on half the plants. Aboveground damage in the first growing season was lowest in Texas and insecticide sprays reduced damage in China. At the end of the first growing season, plants were tallest on an average in China and shortest in Hawaii. However, height in later years and mass were the highest on average in Texas and the lowest in Hawaii. However, there was large variation in damage and plant performance among gardens within venues. Our results suggest that more rapid aboveground growth rates contribute to T. sebifera’s success in both the invasive and native ranges independent of aboveground herbivory. However, strong variation among sites indicates that T. sebifera plants from invasive populations only have a strong advantage in a subset of sites in Texas. PMID:28039113
Siemann, Evan; DeWalt, Saara J; Zou, Jianwen; Rogers, William E
2016-12-30
The success of invasive plants may reflect environmental differences in their native and introduced ranges including both abiotic and biotic conditions, such as release from aboveground herbivory. However, in response to these novel conditions, plants from invasive populations may have higher growth rates and lower defense levels compared to those in the native range. This may contribute to their success in the introduced range but perhaps not in the native range. Here, we grew 1000 Triadica sebifera plants from 14 native and introduced populations in seven common gardens with unmanaged background vegetation for three growing seasons in three geographic venues that varied in T. sebifera status and insect herbivore communities: Texas -T. sebifera is invasive, low levels of generalist herbivory; Hawaii - T. sebifera introduced but not invasive, high levels of generalist herbivory from exotic herbivores; China - native range, both generalist and specialist herbivores. We suppressed aboveground insects with insecticide on half the plants. Aboveground damage in the first growing season was lowest in Texas and insecticide sprays reduced damage in China. At the end of the first growing season, plants were tallest on average in China and shortest in Hawaii. However, height in later years and mass were highest on average in Texas and lowest in Hawaii. However, there was large variation in damage and plant performance among gardens within venues. Our results suggest that more rapid aboveground growth rates contribute to T. sebifera's success in both the invasive and native ranges independent of aboveground herbivory. However, strong variation among sites indicates that T. sebifera plants from invasive populations only have a strong advantage in a subset of sites in Texas. Published by Oxford University Press on behalf of the Annals of Botany Company.
Robotic partial nephrectomy with intracorporeal renal hypothermia using ice slush.
Kaouk, Jihad H; Samarasekera, Dinesh; Krishnan, Jayram; Autorino, Riccardo; Acka, Oktay; Brando, Luis Felipe; Laydner, Humberto; Zargar, Homayoun
2014-09-01
To outline our technique for intracorporeal cooling with ice slush during robotic partial nephrectomy (RPN), with real-time parenchymal temperature monitoring. Eleven consecutive patients with enhancing solid renal masses suitable for treatment with RPN between September 2013 and January 2014 were included in the analysis. Institutional review board approval and informed consent were obtained. Preoperative patient characteristics, intraoperative surgical parameters including patient body temperature and ipsilateral kidney temperature with real-time monitoring, and short-term functional outcomes were analyzed. Median age was 55 years (range, 39-75 years) and American Society of Anesthesiologists score was 3 (range, 2-4). Median tumor size was 4 cm (range, 2.3-7.1) and RENAL nephrometry score was 9 (range, 5-11). One patient had a solitary kidney. During cooling, the lowest median renal parenchymal temperature was 17.05°C (range, 11°C-26°C) and cold ischemia time was 27.17 minutes (range, 18-49 minutes). Median time to latest postoperative estimated glomerular filtration rate was 12 days (range, 2-30 days). Median glomerular filtration rate preservation was 81% (range, 47.9%-126%). There was one positive margin. There were no postoperative complications, and no patients experienced a prolonged ileus. The limitations of this study include a small number of patients and short-term follow-up. RPN with renal hypothermia using intracorporeal ice slush is technically feasible. Our simplified method of introducing the ice slush was free of complications and highly reproducible. The use of a needle temperature probe allowed us to monitor in real time cooling of the renal parenchyma. Copyright © 2014 Elsevier Inc. All rights reserved.
Crocker, D.E.; Kofahl, N.; Fellers, G.D.; Gates, N.B.; Houser, D.S.
2007-01-01
We measured water flux and energy expenditure in free-ranging Point Reyes mountain beavers Aplodontia rufa phaea by using the doubly labeled water method. Previous laboratory investigations have suggested weak urinary concentrating ability, high rates of water flux, and low basal metabolic rates in this species. However, free-ranging measurements from hygric mammals are rare, and it is not known how these features interact in the environment. Rates of water flux (210 ?? 32 mL d-1) and field metabolic rates (1,488 ?? 486 kJ d-1) were 159% and 265%, respectively, of values predicted by allometric equations for similar-sized herbivores. Mountain beavers can likely meet their water needs through metabolic water production and preformed water in food and thus remain in water balance without access to free water. Arginine-vasopressin levels were strongly correlated with rates of water flux and plasma urea : creatinine ratios, suggesting an important role for this hormone in regulating urinary water loss in mountain beavers. High field metabolic rates may result from cool burrow temperatures that are well below lower critical temperatures measured in previous laboratory studies and suggest that thermoregulation costs may strongly influence field energetics and water flux in semifossorial mammals. ?? 2007 by The University of Chicago. All rights reserved.
Deposition rates of viruses and bacteria above the atmospheric boundary layer.
Reche, Isabel; D'Orta, Gaetano; Mladenov, Natalie; Winget, Danielle M; Suttle, Curtis A
2018-04-01
Aerosolization of soil-dust and organic aggregates in sea spray facilitates the long-range transport of bacteria, and likely viruses across the free atmosphere. Although long-distance transport occurs, there are many uncertainties associated with their deposition rates. Here, we demonstrate that even in pristine environments, above the atmospheric boundary layer, the downward flux of viruses ranged from 0.26 × 10 9 to >7 × 10 9 m -2 per day. These deposition rates were 9-461 times greater than the rates for bacteria, which ranged from 0.3 × 10 7 to >8 × 10 7 m -2 per day. The highest relative deposition rates for viruses were associated with atmospheric transport from marine rather than terrestrial sources. Deposition rates of bacteria were significantly higher during rain events and Saharan dust intrusions, whereas, rainfall did not significantly influence virus deposition. Virus deposition rates were positively correlated with organic aerosols <0.7 μm, whereas, bacteria were primarily associated with organic aerosols >0.7 μm, implying that viruses could have longer residence times in the atmosphere and, consequently, will be dispersed further. These results provide an explanation for enigmatic observations that viruses with very high genetic identity can be found in very distant and different environments.
Sohn, J H; Smith, R; Yoong, E; Hudson, N; Kim, T I
2004-01-01
A novel laboratory wind tunnel, with the capability to control factors such as air flow-rate, was developed to measure the kinetics of odour emissions from liquid effluent. The tunnel allows the emission of odours and other volatiles under an atmospheric transport system similar to ambient conditions. Sensors for wind speed, temperature and humidity were installed and calibrated. To calibrate the wind tunnel, trials were performed to determine the gas recovery efficiency under different air flow-rates (ranging from 0.001 to 0.028m3/s) and gas supply rates (ranging from 2.5 to 10.0 L/min) using a standard CO gas mixture. The results have shown gas recovery efficiencies ranging from 61.7 to 106.8%, while the average result from the trials was 81.14%. From statistical analysis, it was observed that the highest, most reliable gas recovery efficiency of the tunnel was 88.9%. The values of air flow-rate and gas supply rate corresponding to the highest gas recovery efficiency were 0.028 m3/s and 10.0 L/min respectively. This study suggested that the wind tunnel would provide precise estimates of odour emission rate. However, the wind tunnel needs to be calibrated to compensate for errors caused by different air flow-rates.
NASA Technical Reports Server (NTRS)
Palmer, Michael T.; Abbott, Kathy H.
1994-01-01
This study identifies improved methods to present system parameter information for detecting abnormal conditions and to identify system status. Two workstation experiments were conducted. The first experiment determined if including expected-value-range information in traditional parameter display formats affected subject performance. The second experiment determined if using a nontraditional parameter display format, which presented relative deviation from expected value, was better than traditional formats with expected-value ranges included. The inclusion of expected-value-range information onto traditional parameter formats was found to have essentially no effect. However, subjective results indicated support for including this information. The nontraditional column deviation parameter display format resulted in significantly fewer errors compared with traditional formats with expected-value-ranges included. In addition, error rates for the column deviation parameter display format remained stable as the scenario complexity increased, whereas error rates for the traditional parameter display formats with expected-value ranges increased. Subjective results also indicated that the subjects preferred this new format and thought that their performance was better with it. The column deviation parameter display format is recommended for display applications that require rapid recognition of out-of-tolerance conditions, especially for a large number of parameters.
Temperature effect on bacterial azo bond reduction kinetics: an Arrhenius plot analysis.
Angelova, Blaga; Avramova, Tatyana; Stefanova, Lilyana; Mutafov, Sava
2008-06-01
Studied was the effect of temperature in the range 12-46 degrees C on the rate of bacterial decolorization of the mono-azo dye Acid Orange 7 by Alcaligenes faecalis 6132 and Rhodococcus erythropolis 24. With both strains the raise of temperature led to a corresponding raise of decolorization rate better manifested by R. erythropolis. The analysis of the Arrhenius plot revealed a break near the middle of the temperature range. The regression analysis showed practically complete identity of the observed break point temperatures (T (BP)): 20.7 degrees C for Alc. faecalis and 20.8 degrees C for R. erythropolis. The values of the activation energy of the decolorization reaction (E (a)) were found to depend on both the organism and the temperature range. In the range below T (BP) the estimated values of E (a) were 138 +/- 7 kJ mol(-1) for Alc. faecalis and 160 +/- 8 kJ mol(-1) for R. erythropolis. In the range above T (BP) they were 54.2 +/- 1.8 kJ mol(-1) for Alc. faecalis and 37.6 +/- 4.1 kJ mol(-1) for R. erythropolis. Discussed are the possible reasons for the observed abrupt change of the activation energy.
NASA Technical Reports Server (NTRS)
Wilson, D. J.; Krause, M. C.; Coffey, E. W.; Huang, C. C.; Edwards, B. B.; Shrider, K. R.; Jetton, J. L.; Morrison, L. K.
1974-01-01
A servo-controlled range/elevation scanner for the laser Doppler velocimeter (LDV) was developed and tested in the field to assess its performance in detecting and monitoring aircraft trailing vortices in an airport environment. The elevation scanner provides a capability to manually point the LDV telescope at operator chosen angles from 3.2 deg. to 89.6 deg within 0.2 deg, or to automatically scan the units between operator chosen limits at operator chosen rates of 0.1 Hz to 0.5 Hz. The range scanner provides a capability to manually adjust the focal point of the system from a range of 32 meters to a range of 896 meters under operator control, or to scan between operator chosen limits and at rates from 0.1 Hz to 6.9 Hz. The scanner controls are designed to allow simulataneous range and elevation scanning so as to provide finger scan patterns, arc scan patterns, and vertical line scan patterns. The development and testing of the unit is discussed, along with a fluid dynamic model of the wake vortex developed in a laser Doppler vortex sensor simulation program.
Pulse homodyne field disturbance sensor
McEwan, Thomas E.
1997-01-01
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudo-randomly modulated so that bursts in the sequence of bursts have a phase which varies. A second range-defining mode transmits two radio frequency bursts, where the time spacing between the bursts defines the maximum range divided by two.
Pulse homodyne field disturbance sensor
McEwan, T.E.
1997-10-28
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudo-randomly modulated so that bursts in the sequence of bursts have a phase which varies. A second range-defining mode transmits two radio frequency bursts, where the time spacing between the bursts defines the maximum range divided by two. 12 figs.
Absorption performance for CO2 capture process using MDEA-AMP aqueous solution
NASA Astrophysics Data System (ADS)
Liu, Gang; Kou, Liqing; Li, Chao
2017-03-01
The absorption capacity and the absorption rate of CO2 in 2-amino-2-methyl-1-propanol (AMP)-N-methyldiethanolamine (MDEA) aqueous solution were measured. The temperatures ranged from 303.2K to 323.2K. The mass fractions of AMP and MDEA respectively ranged from 0 to 0.03 and 0.2 to 0.3. The influence of temperature and w AMP on the absorption capacity and absorption rate of CO2 was illustrated.
NASA Astrophysics Data System (ADS)
Owen, Lewis A.; Davis, Teresa; Caffee, Marc W.; Budinger, Fred; Nash, David
2011-01-01
Erosion rates and surface exposure ages were determined at the Calico Archaeological Site in the Calico Hills of the Mojave Desert, California, using 10Be terrestrial cosmogenic nuclides (TCN) methods. The Calico Hills are composed of Miocene lacustrine deposits of the Barstow Formation and fanglomerates/debris flows of the Pleistocene Yermo Deposits. These deposits are highly denuded and dissected by arroyos that have surfaces armored with chert. Surface erosion rates based on cosmogenic 10Be concentrations in stream sediments range from 19 to 39 m/Ma, with an average of 30.5 ± 6.2 m/Ma. Surface boulders have 10Be TCN ages that range from 27 ka to 198 ka, reflecting significant erosion of the Calico Hills. The oldest boulder age (197 ± 20 ka) places a minimum limit on the age of Yermo deposits. Depth profile ages at four locations within the study area have minimum ages that range from 31 to 84 ka and erosion rate-corrected surface exposure ages ranging from 43 to 139 ka. These surface exposure ages support the view that the surfaces in Yermo deposits formed during the Late Pleistocene to latest Middle Pleistocene. This chronology has important implications for interpreting the context of possible artifacts/geofacts at the site that might provide evidence for early human occupation of North America, and for reconstructing paleoenvironment change and landscape evolution in the region.
Shi, Chengcheng; Jiang, Shaosong; Zhang, Kaifeng
2017-01-01
This paper focuses on the fabrication of as-forged Ti46.5Al2Cr1.8Nb-(W, B) alloy via pulse current auxiliary isothermal forging (PCIF). The starting material composed of near gamma (NG) microstructure was fabricated by adopting pre-alloyed powders via hot pressing sintering (HPS) at 1300 °C. Isothermal compression tests were conducted at a strain rate range of 0.001–0.1 s−1 and a temperature range of 1125–1275 °C to establish the constitutive model and processing map. The optimal hot deformation parameters were successfully determined (in a strain rate range of 10−3–2.5 × 10−3 s−1 and temperature range of 1130–1180 °C) based on the hot processing map and microstructure observation. Accordingly, an as-forged TiAl based alloy without cracks was successfully fabricated by PCIF processing at 1175 °C with a nominal strain rate of 10−3 s−1. Microstructure observation indicated that complete dynamic recrystallization (DRX) and phase transformation of γ→α2 occurred during the PCIF process. The elongation of as-forged alloy was 136%, possessing a good secondary hot workability, while the sintered alloy was only 66% when tested at 900 °C with a strain rate of 2 × 10−4 s−1. PMID:29258198
Determination of sex from the hyoid bone in a contemporary White population.
Logar, Ciara J; Peckmann, Tanya R; Meek, Susan; Walls, Stephen G
2016-04-01
Six discriminant functions, developed from an historic White population, were tested on a contemporary White population for determination of sex from the hyoid. One hundred and thirty four fused and unfused hyoids from a contemporary White population were used. Individuals ranged between 20 and 49 years old. Six historic White discriminant functions were applied to the fused and unfused hyoids of the pooled contemporary White population, i.e. all males and females and all age ranges combined. The overall accuracy rates were between 72.1% and 92.3%. Correct sex determination for contemporary White males ranged between 88.2% and 96.3%, while correct sex determination for contemporary White females ranged between 31.3% and 92.0%. Discriminant functions were created for the contemporary White population with overall mean accuracy rates between 67.0% and 93.0%. The multivariate discriminant function overall accuracy rates were between 89.0% and 93.0% and the univariate discriminant function overall accuracy rates were between 67.0% and 86.8%. The contemporary White population data were compared to other populations and showed significant differences between many of the variables measured. This study illustrated the need for population-specific and temporally-specific discriminant functions for determination of sex from the hyoid bone. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Shi, Chengcheng; Jiang, Shaosong; Zhang, Kaifeng
2017-12-16
This paper focuses on the fabrication of as-forged Ti46.5Al2Cr1.8Nb-(W, B) alloy via pulse current auxiliary isothermal forging (PCIF). The starting material composed of near gamma (NG) microstructure was fabricated by adopting pre-alloyed powders via hot pressing sintering (HPS) at 1300 °C. Isothermal compression tests were conducted at a strain rate range of 0.001-0.1 s -1 and a temperature range of 1125-1275 °C to establish the constitutive model and processing map. The optimal hot deformation parameters were successfully determined (in a strain rate range of 10 -3 -2.5 × 10 -3 s -1 and temperature range of 1130-1180 °C) based on the hot processing map and microstructure observation. Accordingly, an as-forged TiAl based alloy without cracks was successfully fabricated by PCIF processing at 1175 °C with a nominal strain rate of 10 -3 s -1 . Microstructure observation indicated that complete dynamic recrystallization (DRX) and phase transformation of γ→α₂ occurred during the PCIF process. The elongation of as-forged alloy was 136%, possessing a good secondary hot workability, while the sintered alloy was only 66% when tested at 900 °C with a strain rate of 2 × 10 -4 s -1 .
Hot deformation characteristics of INCONEL alloy MA 754 and development of a processing map
DOE Office of Scientific and Technical Information (OSTI.GOV)
Somani, M.C.; Muraleedharan, K.; Birla, N.C.
1994-08-01
The characteristics of hot deformation of INCONEL alloy MA 754 have been studies using processing maps obtained on the basis of flow stress data generated in compression in the temperature range 700 C to 1,150 C and strain rate range 0.001 to 100 s[sup [minus]1]. The map exhibited three domains. (1) A domain of dynamic recovery occurs in the temperature range 800 C to 1,075 C and strain rate range 0.02 to 2 s[sup [minus]1], with a peak efficiency of 18 pct occurring at 950 C and 0.1 s [sup [minus]1]. Transmission electron microscope (TEM) micrographs revealed stable subgrain structuremore » in this domain with the subgrain size increasing exponentially with an increase in temperature. (2) A domain exhibiting grain boundary cracking occurs at temperatures lower than 800 C and strain rates lower than 0.01 s[sup [minus]1]. (3) A domain exhibiting intense grain boundary cavitation occurs at temperatures higher than 1075 C. The material did not exhibit a dynamic recrystallization (DRX) domain, unlike other superalloys. At strain rates higher than about 1 s[sup [minus]1], the material exhibits flow instabilities manifesting as kinking of the elongated grains and adiabatic shear bands. The materials may be safely worked in the domain of dynamic recovery but can only be statically recrystallized.« less
Bevelhimer, Mark S.; Stewart, Aurthur J.; Fortner, Allison M.; ...
2016-01-06
During August-September 2012, we sampled six hydropower reservoirs in southeastern United States. for CO 2 and CH 4 emissions via three pathways: diffusive emissions from water surface; ebullition in the water column; and losses from dam tailwaters during power generation. Average total emission rates of CO 2 for the six reservoirs ranged from 1,127 to 2,051 mg m -2 d -1, which is low to moderate compared to CO 2 emissions rates reported for tropical hydropower reservoirs and boreal ponds and lakes, and similar to rates reported for other temperate reservoirs. Similar average rates for CH 4 were also relativelymore » low, ranging from 5 to 83 mg m -2 d -1. On a whole-reservoir basis, total emissions of CO 2 ranged nearly 10-fold, from ~51,000 kg per day for Fontana to ~486,000 kg per day for Guntersville, and total emissions of CH 4 ranged nearly 20-fold, from ~5 kg per day for Fontana to ~83 kg per day for Allatoona. Emissions through the tailwater pathway varied among reservoirs, comprising from 20 to 50% of total CO 2 emissions and 0 to 90% of CH 4 emissions, depending on the reservoir. Furthermore, several explanatory factors related to reservoir morphology and water quality were considered for observed differences among reservoirs.« less
Sun, Jun; Liu, Dongyan; Wang, Zonglin; Shi, Xiaoyong; Li, Ruixiang; Zhu, Mingyuan
2003-07-01
Five typical stations in the Changjiang River estuary and adjacent waters of the East China Sea, were chosen as the sites to study phytoplankton growth and microzooplankton ingestion by on-deck-incubation dilution experiment from 25th April to 25th May 2002. The results showed that microzooplankton ingestion was a key process for controlling red tide event. Strombidium sulcatum, Noctiluca scintillans and Mesodinium robudium were dominant microzooplankton species. In this study, the ingestion rate of microzooplankton ranged from 0.28 to 1.13 d-1; ingestion pressure on percentage of phytoplankton standing crop ranged from 35.14% to 811.69%; ingestion pressure on percentage of potential production ranged from 74.04% to 203.25%; and ingestion rate of phytoplankton carbon ranged from 9.58 to 97.91 C.L-1.d-1. The microzooplankton grazing rate, ingestion pressure on percentage of phytoplankton standing crop, and ingestion rate of phytoplankton carbon were higher near coastal area, but lower at open sea, and the microzooplankton ingestion pressure on percentage of phytoplankton potential production was no the contrary. Compared with the similar studies around the world, the ingestion pressure of microzooplankton in the East China Sea was at a higher level. The primary deduction was that Strombidium was the key microzooplankton species on controlling Prorocentrum dentatum, the most important red tide species in the East China Sea.
The structure and productivity of the Thalassia testudinum community in Bon Accord Lagoon, Tobago.
Juman, Rahanna A
2005-05-01
The Thalassia testudinum dominated seagrass community in the Buccoo Reef/ Bon Accord Lagoon Marine Park, measures 0.5 km(2) and is part of a contiguous coral reef, seagrass bed and mangrove swamp system in southwest Tobago. 7 testudinum coverage, productivity and percent turnover rates were measured from February 1998 to February 1999 at four sample locations, while total T. testudinum biomass was measured at two locations in the lagoon from 1992-2002. Productivity and turnover rates varied spatially and seasonally. They were higher in the back-reef area than in the mangrove-fringed lagoon, and were lowest at locations near to a sewage outfall. 7 testudinum coverage ranged from 6.6% in the lagoon to 68.5% in the back-reef area while productivity ranged from 3.9 to 4.9 g dry wt m(-2) d(-1) . Productivity and percentage turnover rates were higher in the dry season (January-June) than in the wet season (July-December). Productivity ranged from 3.0 in the wet season to 5.0 g dry wt m2 d-' in the dry season while percentage turnover rates ranged from 4.2% to 5.6%. Total Thalassia biomass and productivity in Bon Accord Lagoon were compared to six similar sites in the Caribbean that also participate in the Caribbean Coastal Marine Productivity Program (CARICOMP). This seagrass community is being negatively impacted by nutrient-enriched conditions.
Rates and style of Cenozoic deformation around the Gonghe Basin, northeastern Tibetan Plateau
Craddock, William H.; Kirby, Eric; Zhang, Huiping; Clark, Marin K.; Champagnac, Jean-Daniel; Yuan, Daoyang
2014-01-01
The northeastern Tibetan Plateau constitutes a transitional region between the low-relief physiographic plateau to the south and the high-relief ranges of the Qilian Shan to the north. Cenozoic deformation across this margin of the plateau is associated with localized growth of fault-cored mountain ranges and associated basins. Herein, we combine detailed structural analysis of the geometry of range-bounding faults and deformation of foreland basin strata with geomorphic and exhumational records of erosion in hanging-wall ranges in order to investigate the magnitude, timing, and style of deformation along the two primary fault systems, the Qinghai Nan Shan and the Gonghe Nan Shan. Structural mapping shows that both ranges have developed above imbricate fans of listric thrust faults, which sole into décollements in the middle crust. Restoration of shortening along balanced cross sections suggests a minimum of 0.8–2.2 km and 5.1–6.9 km of shortening, respectively. Growth strata in the associated foreland basin record the onset of deformation on the two fault systems at ca. 6–10 Ma and ca. 7–10 Ma, respectively, and thus our analysis suggests late Cenozoic shortening rates of 0.2 +0.2/–0.1 km/m.y. and 0.7 +0.3/–0.2 km/m.y. along the north and south sides of Gonghe Basin. Along the Qinghai Nan Shan, these rates are similar to late Pleistocene slip rates of ∼0.10 ± 0.04 mm/yr, derived from restoration and dating of a deformed alluvial-fan surface. Collectively, our results imply that deformation along both flanks of the doubly vergent Qilian Shan–Nan Shan initiated by ca. 10 Ma and that subsequent shortening has been relatively steady since that time.
Mapping the dense scotoma and its enlargement in Stargardt disease
Bernstein, Aryeh; Sunness, Janet S.; Applegate, Carol A.; Tegins, Elizabeth O.
2016-01-01
Purpose To describe the enlargement of the dense scotoma over time in Stargardt disease, and to highlight methodological issues in tracking enlargement. Methods Retrospective study of patients with full mapping of the border of the dense scotoma using the MP-1 for at least two visits. Results Fourteen eyes of 7 patients met this criterion. Patients had median of 3 visits (range 2 to 5), with median total f/u of 4.5 years (range 1.5-8). Mean baseline visual acuity was 20/56 (range 20/25-20/200), mean baseline dense scotoma area was 2.23mm2 (range 0.41-5.48), and mean dense scotoma enlargement rate was 1.36mm2/year (range 0.22-2.91). The younger patients tended to have more rapid loss of visual acuity, which tended to plateau when the VA was 20/100 or worse. The patients who developed Stargardt before age 20, and the single patient who developed Stargardt disease after age 40, had more rapid enlargement rates, with preservation of central vision in the oldest patient. The ability to precisely define the dense scotoma area was dependent upon the density location of the points tested; this led to significant variability in the assessment of the scotoma enlargement rate in 3 of the 7 patients. The dense scotoma was not described adequately by the extent of the homogeneous dark area on fundus autofluorescence imaging. Conclusion Microperimetry is necessary for mapping the scotoma in patients with Stargardt disease, since current imaging is not adequate. Standardized grid testing, plus a standardized procedure for refining the border of the dense scotoma, should allow more precise testing and longitudinal assessment of enlargement rates. PMID:26909568
18F-choline PET/MRI in suspected recurrence of prostate carcinoma.
Riola-Parada, C; Carreras-Delgado, J L; Pérez-Dueñas, V; Garcerant-Tafur, M; García-Cañamaque, L
2018-05-21
To evaluate the usefulness of simultaneous 18 F-choline PET/MRI in the suspicion of prostate cancer recurrence and to relate 18 F-choline PET/MRI detection rate with analytical and pathological variables. 27 patients with prostate cancer who received local therapy as primary treatment underwent a 18 F-choline PET/MRI due to suspicion of recurrence (persistently rising serum PSA level). 18 F-choline PET/MRI findings were validated by anatomopathological analysis, other imaging tests or by biochemical response to oncological treatment. 18 F-choline PET/MRI detected disease in 15 of 27 patients (detection rate 55.56%). 4 (15%) presented exclusively local recurrence, 5 (18%) lymph node metastases and 7 (26%) bone metastases. Mean PSA (PSA med ) at study time was 2.94ng/mL (range 0.18-10ng/mL). PSA med in patients with positive PET/MRI was 3.70ng/mL (range 0.24-10ng/mL), higher than in patients with negative PET/MRI, PSA med 1.97ng/mL (range 0.18-4.38ng/mL), although without statistically significant differences. Gleason score at diagnosis in patients with a positive study was 7.33 (range 6-9) and in patients with a negative study was 7 (range 6-9), without statistically significant differences. 18 F-choline PET/MRI detection rate was considerable despite the relatively low PSA values in our sample. The influence of Gleason score and PSA level on 18 F-choline PET/MRI detection rate was not statistically significant. Copyright © 2018 Sociedad Española de Medicina Nuclear e Imagen Molecular. Publicado por Elsevier España, S.L.U. All rights reserved.
Ruthenium brachytherapy for uveal melanoma - single institution experience.
Rospond-Kubiak, Iwona; Wróblewska-Zierhoffer, Marta; Twardosz-Pawlik, Hanna; Kocięcki, Jarosław
2017-12-01
The aim of this study was to report on results of uveal melanoma treatment with ruthenium-106 ( 106 Ru) brachytherapy with long-term follow-up, in terms of local tumor control, eye retention rate, radiation retinopathy, and patients' survival. Medical records of patients treated with ruthenium plaque due to uveal melanoma at the Department of Ophthalmology, Poznan University of Medical Sciences, Poland, between 1994 and 2014 were retrospectively reviewed. We identified 126 patients: 53 men, 73 women, mean age 60.04 years (range, 21-89). The largest basal diameter ranged from 4.04 mm to 18.9 mm (median, 10.67 mm), tumor height was 1.9 mm to 7.42 mm (median, 4.8 mm). Median scleral radiation dose was 570 Gy (range, 235-1,500 Gy), median apical dose 100 Gy (range, 60-129 Gy). Median follow-up was 66.5 months (range, 2-261 months). We noted a total of 19 (15%) recurrences. The actuarial rate of recurrence was 9.5% at 3 years, and 13.5% at 5 years postoperatively. Nine (7%) eye globes were lost, median time to enucleation was 5 years. The eye retention rate at 5 years was 92.7% and 81% at 10 years. Forty-three (34%) patients died before the end of the study, 24 (19%) of them due to metastatic disease. Metastatic death was related to: tumor size and TNM stage at presentation ( p = 0.002 vs. p = 0.0006, respectively) but not to age, gender, and plaque dosimetry. 106 Ru brachytherapy is an effective, globe sparing treatment that provides good tumor control and a high rate of survival. However, some ocular complications tend to appear late post-treatment, and therefore long-term follow-up is advised.
Howie, Erin K; Straker, Leon M
2016-10-01
The purpose of this brief review was to describe the missingness, from both attrition and non-compliance, during physical activity randomized controlled trials among children which have used accelerometers to measure physical activity. Systematic review. Using a previously published search strategy, an updated search of the literature was performed in the MEDLINE database for articles published from 1996 to February 2015 identifying physical activity RCTs in children (ages 2-18) measuring physical activity using accelerometers. Rates of attrition and non-compliance were extracted from identified articles. Twenty-three independent studies provided complete attrition and non-compliance data and were included. The mean attrition rate was 11.5% (SD 10.1%, range 0-30.9%). The mean accelerometer non-compliance rate at baseline was 22.7% (SD 16.4%, range 1.7-67.8%) and 29.6% (SD 19.4%, range 3.3-70.1%) at follow-up. The mean total study missingness was 37.4% (SD 20.2%, range 3.3-75.4%) and ranged from 3.3% to 75.4%. There was large variation in how missingness was accounted for between studies. There were no statistically significant differences in missingness between study characteristics including sample size, participant age, intervention setting, duration of follow-up, whether physical activity was the primary outcome, and weartime compliance criteria. Missingness is common among randomized controlled trials using accelerometry in children and is currently handled inconsistently. Researchers must plan for high levels of missingness in study design and account for missingness in reporting and analyses of trial outcomes. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Kinetics of the solid-state carbothermic reduction of wessel manganese ores
NASA Astrophysics Data System (ADS)
Akdogan, Guven; Eric, R. Hurman
1995-02-01
Reduction of manganese ores from the Wessel mine of South Africa has been investigated in the temperature range 1100 °C to 1350 °C with pure graphite as the reductant under argon atmosphere. The rate and degree of reduction were found to increase with increasing temperature and decreasing particle sizes of both the ore and the graphite. The reduction was found to occur in two stages: (1) The first stage includes the rapid reduction of higher oxides of manganese and iron to MnO and FeO. The rate control appears to be mixed, both inward diffusion of CO and outward diffusion of CO2 across the porous product layer, and the reaction of carbon monoxide on the pore walls of the oxide phase play important roles. The values of effective CO-CO2 diffusivities generated by the mathematical model are in the range from 2.15 x 10-5 to 6.17 X 10-5 cm2.s-1 for different ores at 1300 °C. Apparent activation energies range from 81. 3 to 94.6 kJ/kg/mol. (2) The second stage is slower during which MnO and FeO are reduced to mixed carbide of iron and manganese. The chemical reaction between the manganous oxide and carbon dissolved in the metal phase or metal carbide seems to be the rate-controlling process The rate constant of chemical reaction between MnO and carbide on the surface of the impervious core was found to lie in the range from 1.53 x 10-8 to 1.32 x 10-7 mol . s-1 . cm-2. Apparent activation energies calculated are in the range from 102.1 to 141.7 kJ/kg/mol.
Assessment of range planting as a conservation practice
Stuart P. Hardegree; Thomas A. Jones; Bruce A. Roundy; Nancy L. Shaw; Thomas A. Monaco
2016-01-01
Natural Resource Conservation Service Range Planting - Conservation Practice Standards provide guidelines for making decisions about seedbed preparation, planting methods, plant materials selection, seeding rate, seeding depth, timing of seeding, postplanting management, and weed control. Adoption of these standards is expected to contribute to successful...
Integrated communications and optical navigation system
NASA Astrophysics Data System (ADS)
Mueller, J.; Pajer, G.; Paluszek, M.
2013-12-01
The Integrated Communications and Optical Navigation System (ICONS) is a flexible navigation system for spacecraft that does not require global positioning system (GPS) measurements. The navigation solution is computed using an Unscented Kalman Filter (UKF) that can accept any combination of range, range-rate, planet chord width, landmark, and angle measurements using any celestial object. Both absolute and relative orbit determination is supported. The UKF employs a full nonlinear dynamical model of the orbit including gravity models and disturbance models. The ICONS package also includes attitude determination algorithms using the UKF algorithm with the Inertial Measurement Unit (IMU). The IMU is used as the dynamical base for the attitude determination algorithms. This makes the sensor a more capable plug-in replacement for a star tracker, thus reducing the integration and test cost of adding this sensor to a spacecraft. Recent additions include an integrated optical communications system which adds communications, and integrated range and range rate measurement and timing. The paper includes test results from trajectories based on the NASA New Horizons spacecraft.
Mechanical Behavior and Microstructure Evolution of Bearing Steel 52100 During Warm Compression
NASA Astrophysics Data System (ADS)
Huo, Yuanming; He, Tao; Chen, Shoushuang; Wu, Riming
2018-05-01
High-performance bearing steel requires a fine and homogeneous structure of carbide particles. Direct deformation spheroidizing of bearing steel in a dual-phase zone can contribute to achieving this important structure. In this work, warm compression testing of 52100 bearing steel was performed at temperatures in the range of 650-850°C and at strain rates of 0.1-10.0 s-1. The effect of deformation temperatures on mechanical behavior and microstructure evolution was investigated to determine the warm deformation temperature window. The effect of deformation rates on microstructure evolution and metal flow softening behavior of the warm compression was analyzed and discussed. Experimental results showed that the temperature range from 750°C to 800°C should be regarded as the critical range separating warm and hot deformation. Warm deformation at temperatures in the range of 650-750°C promoted carbide spheroidization, and this was determined to be the warm deformation temperature window. Metal flow softening during the warm deformation was caused by carbide spheroidization.
Automatic dilution gaging of rapidly varying flow
Duerk, M.D.
1983-01-01
The analysis showed that the discharges measured by dye-dilution techniques were generally within ± 10 percent of the discharges determined from ratings established by current-meter measurements. Larger differences were noted at the start of and on the rising limb of four hydrographs. Of the 20 storms monitored, dilution measurements on 17 were of acceptable accuracy. Peak discharges from the open-channel site ranged from 0 to 12 percent departures from the existing rating whereas the comparison of peak discharge at the storm sewer site ranged from 0 to 5 percent departures from the existing rating.
NASA Technical Reports Server (NTRS)
Jameson, A. R.
1990-01-01
The relationship between the rainfall rate (R) obtained from radiometric brightness temperatures and the extinction coefficient (k sub e) is investigated by computing the values of k sub e over a wide range of rainfall rates, for frequencies from 3 to 25 GHz. The results show that the strength of the relation between the R and the k sub e values exhibits considerable variation for frequencies at this range. Practical suggestions are made concerning the selection of particular frequencies for rain measurements to minimize the error in R determinations.
New test of general relativity - Measurement of de Sitter geodetic precession rate for lunar perigee
NASA Technical Reports Server (NTRS)
Bertotti, Bruno; Ciufolini, Ignazio; Bender, Peter L.
1987-01-01
According to general relativity, the calculated rate of motion of lunar perigee should include a contribution of 19.2 msec/yr from geodetic precession. It is shown that existing analyses of lunar-laser-ranging data confirm the general-relativistic rate for geodetic precession with respect to the planetary dynamical frame. In addition, the comparison of earth-rotation results from lunar laser ranging and from VLBI shows that the relative drift of the planetary dynamical frame and the extragalactic VLBI reference frame is small. The estimated accuracy is about 10 percent.
Image interpolation used in three-dimensional range data compression.
Zhang, Shaoze; Zhang, Jianqi; Huang, Xi; Liu, Delian
2016-05-20
Advances in the field of three-dimensional (3D) scanning have made the acquisition of 3D range data easier and easier. However, with the large size of 3D range data comes the challenge of storing and transmitting it. To address this challenge, this paper presents a framework to further compress 3D range data using image interpolation. We first use a virtual fringe-projection system to store 3D range data as images, and then apply the interpolation algorithm to the images to reduce their resolution to further reduce the data size. When the 3D range data are needed, the low-resolution image is scaled up to its original resolution by applying the interpolation algorithm, and then the scaled-up image is decoded and the 3D range data are recovered according to the decoded result. Experimental results show that the proposed method could further reduce the data size while maintaining a low rate of error.
Home range and movements of Feral cats on Mauna Kea, Hawai'i
Goltz, Dan M.; Hess, S.C.; Brinck, K.W.; Banko, P.C.; Danner, R.M.
2008-01-01
Feral cats Felis catus in dry subalpine woodland of Mauna Kea, Hawai'i, live in low density and exhibit some of the largest reported home ranges in the literature. While 95% fixed kemel home range estimates for three females averaged 772 ha, four males averaged 1 418 ha, and one male maintained a home range of 2 050 ha. Mean daily movement rates between sexes overlapped widely and did not differ significantly (P = 0.083). Log-transformed 95% kernel home ranges for males were significantly larger than those of females (P = 0.024), but 25% kernel home ranges for females were larger than those of males (P = 0.017). Moreover, log-transformed home ranges of males were also significantly larger than those of females in this and seven other studies from the Pacific region (P = 0.044). Feral cats present a major threat to endangered Hawaiian birds, but knowledge of their ecology can be used for management by optimizing trap spacing and creating buffer zones around conservation areas.
Strona, Giovanni; Galli, Paolo; Montano, Simone; Seveso, Davide; Fattorini, Simone
2012-01-01
Although fish range sizes are expected to be associated with species dispersal ability, several studies failed to find a clear relationship between range size and duration of larval stage as a measure of dispersal potential. We investigated how six characteristics of the adult phase of fishes (maximum body length, growth rate, age at first maturity, life span, trophic level and frequency of occurrence) possibly associated with colonization ability correlate with range size in both freshwater and marine species at global scale. We used more than 12 million point records to estimate range size of 1829 freshwater species and 10068 marine species. As measures of range size we used both area of occupancy and extent of occurrence. Relationships between range size and species traits were assessed using Canonical Correlation Analysis. We found that frequency of occurrence and maximum body length had a strong influence on range size measures, which is consistent with patterns previously found (at smaller scales) in several other taxa. Freshwater and marine fishes showed striking similarities, suggesting the existence of common mechanisms regulating fish biogeography in the marine and freshwater realms.
Self-contained eye-safe laser radar using an erbium-doped fiber laser
NASA Astrophysics Data System (ADS)
Driscoll, Thomas A.; Radecki, Dan J.; Tindal, Nan E.; Corriveau, John P.; Denman, Richard
2003-07-01
An Eye-safe Laser Radar has been developed under White Sands Missile Range sponsorship. The SEAL system, the Self-contained Eyesafe Autonomous Laser system, is designed to measure target position within a 0.5 meter box. Targets are augmented with Scotchlite for ranging out to 6 km and augmented with a retroreflector for targets out to 20 km. The data latency is less than 1.5 ms, and the position update rate is 1 kHz. The system is air-cooled, contained in a single 200-lb, 6-cubic-foot box, and uses less than 600 watts of prime power. The angle-angle-range data will be used to measure target dynamics and to control a tracking mount. The optical system is built around a diode-pumped, erbium-doped fiber laser rated at 1.5 watts average power at 10 kHz repetition rate with 25 nsec pulse duration. An 8 inch-diameter, F/2.84 telescope is relayed to a quadrant detector at F/0.85 giving a 5 mrad field of view. Two detectors have been evaluated, a Germanium PIN diode and an Intevac TE-IPD. The receiver electronics uses a DSP network of 6 SHARC processors to implement ranging and angle error algorithms along with an Optical AGC, including beam divergence/FOV control loops.Laboratory measurements of the laser characteristics, and system range and angle accuracies will be compared to simulations. Field measurements against actual targets will be presented.
The effects of vertical motion on the performance of current meters
Thibodeaux, K.G.; Futrell, J. C.
1987-01-01
A series of tests to determine the correction coefficients for Price type AA and Price type OAA current meters, when subjected to vertical motion in a towing tank, have been conducted. During these tests, the meters were subjected to vertical travel that ranged from 1.0 to 4.0 ft and vertical rates of travel that ranged from 0.33 to 1.20 ft/sec while being towed through the water at speeds ranging from 0 to 8 ft/sec. The tests show that type AA and type OAA current meters are affected adversely by the rate of vertical motion and the distance of vertical travel. In addition, the tests indicate that when current meters are moved vertically, correction coefficients must be applied to the observed meter velocities to correct for the registration errors that are induced by the vertical motion. The type OAA current meter under-registers and the type AA current meter over-registers in observed meter velocity. These coefficients for the type OAA current meter range from 0.99 to 1.49 and for the type AA current meter range from 0.33 to 1.07. When making current meter measurements from a boat or a cableway, errors in observed current meter velocity will occur when the bobbing of a boat or cableway places the current meter into vertical motion. These errors will be significant when flowing water is < 2 ft/sec and the rate of vertical motion is > 0.3 ft/sec. (Author 's abstract)
A systematic review of population based epidemiological studies in Myasthenia Gravis
2010-01-01
Background The aim was to collate all myasthenia gravis (MG) epidemiological studies including AChR MG and MuSK MG specific studies. To synthesize data on incidence rate (IR), prevalence rate (PR) and mortality rate (MR) of the condition and investigate the influence of environmental and technical factors on any trends or variation observed. Methods Studies were identified using multiple sources and meta-analysis performed to calculate pooled estimates for IR, PR and MR. Results 55 studies performed between 1950 and 2007 were included, representing 1.7 billion population-years. For All MG estimated pooled IR (eIR): 5.3 per million person-years (C.I.:4.4, 6.1), range: 1.7 to 21.3; estimated pooled PR: 77.7 per million persons (C.I.:64.0, 94.3), range 15 to 179; MR range 0.1 to 0.9 per millions person-years. AChR MG eIR: 7.3 (C.I.:5.5, 7.8), range: 4.3 to 18.0; MuSK MG IR range: 0.1 to 0.32. However marked variation persisted between populations studied with similar methodology and in similar areas. Conclusions We report marked variation in observed frequencies of MG. We show evidence of increasing frequency of MG with year of study and improved study quality. This probably reflects improved case ascertainment. But other factors must also influence disease onset resulting in the observed variation in IR across geographically and genetically similar populations. PMID:20565885
Interactions regulating the head-to-tail directed assembly of biological Janus rods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greene, A. C.; Bachand, M.; Gomez, A.
We can generalize the directed, head-to-tail self-assembly of microtubule filaments in the context of Janus colloidal rods. Specifically, their assembly at the tens of micron-length scale involves a careful balance between long-range electrostatic repulsion and short-range attractive forces. We show that the addition of counterion salts increases the rate of directed assembly by screening the electrostatic forces and enhancing the effectiveness of short-range interactions at the microtubule ends.
Development of a Low cost Ultra tiny Line Laser Range Sensor
2016-12-01
Development of a Low-cost Ultra-tiny Line Laser Range Sensor Xiangyu Chen∗, Moju Zhao∗, Lingzhu Xiang†, Fumihito Sugai∗, Hiroaki Yaguchi∗, Kei Okada...and Masayuki Inaba∗ Abstract— To enable robotic sensing for tasks with require- ments on weight, size, and cost, we develop an ultra-tiny line laser ...view customizable using different laser lenses. The optimal measurement range of the sensor is 0.05[m] ∼ 2[m]. Higher sampling rates can be achieved
Interactions regulating the head-to-tail directed assembly of biological Janus rods
Greene, A. C.; Bachand, M.; Gomez, A.; ...
2017-03-31
We can generalize the directed, head-to-tail self-assembly of microtubule filaments in the context of Janus colloidal rods. Specifically, their assembly at the tens of micron-length scale involves a careful balance between long-range electrostatic repulsion and short-range attractive forces. We show that the addition of counterion salts increases the rate of directed assembly by screening the electrostatic forces and enhancing the effectiveness of short-range interactions at the microtubule ends.
Lilies at the limit: Variation in plant-pollinator interactions across an elevational range.
Theobald, Elli J; Gabrielyan, Hrach; HilleRisLambers, Janneke
2016-02-01
Many studies assume climatic factors are paramount in determining species' distributions, however, biotic interactions may also play a role. For example, pollinators may limit species' ranges if floral abundance or floral attractiveness is reduced at range margins, thus causing lower pollinator visitation and reduced reproductive output. To test if pollinators influence the altitudinal distribution of Erythronium montanum (Liliaceae) at Mount Rainier National Park, we asked whether (1) seed production in this species relies on pollinators, (2) seed production and pollen limitation is greatest at range limits, and (3) pollinator visitation rates (either overall or by individual taxonomic groups) reflect patterns of seed production and pollen limitation. From this three-year study, we established that this plant does rely on pollinators for fruit set and we found that pollen limitation trended toward being higher at the upper range limit in some years, but not consistently year to year. Insect visitation rates did not mirror spatial patterns of pollen limitation, but annually variable pollinator composition suggested differential importance of some pollinator taxonomic groups (specifically, bumblebees may be better pollinators than syrphid flies). Overall, these results suggest that while pollinators are critical for the reproductive success of this high mountain wildflower, plant-pollinator interactions do not obviously drive the distribution of this species. Nonetheless, high spatio-temporal variability in range-wide plant-pollinator dynamics may complicate responses to climate change. © 2016 Botanical Society of America.
Effects of box handle position and carrying range on bi-manual carrying capacity for females.
Wu, Swei-Pi; Loiu, Yi; Chien, Te Hong
2015-01-01
This study utilizes a psychophysical approach to examine the effects on carrying capacity for bi-manual carrying tasks involving different handle positions and carrying ranges. A total of 16 female subjects participated in the experiment in groups of two people, and each group of subjects performed the tasks in a random order with 12 different combinations of carrying task. The independent variables are handle position (upper, middle, lower) and carrying range (F-F: floor height carried to floor height, F-W: floor height carried to waist height, W-W: waist height carried to waist height, W-F: waist height carried to floor height), the dependent variable is the maximum acceptable carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The results show that the handle position has a significant effect on MAWC and overall RPE but no significant effect on HR. Carrying range has a significant effect on the MAWC and HR, but no significant effect on overall HR. The handle position and carrying range have a significant interaction on the MAWC and HR. The RPE for different body parts shows significant differences, and the hands feel the most tired. Overall, this study confirms that the lower handle position with the W-W carrying range is the best combination for a two-person carrying task.
Basis convergence of range-separated density-functional theory.
Franck, Odile; Mussard, Bastien; Luppi, Eleonora; Toulouse, Julien
2015-02-21
Range-separated density-functional theory (DFT) is an alternative approach to Kohn-Sham density-functional theory. The strategy of range-separated density-functional theory consists in separating the Coulomb electron-electron interaction into long-range and short-range components and treating the long-range part by an explicit many-body wave-function method and the short-range part by a density-functional approximation. Among the advantages of using many-body methods for the long-range part of the electron-electron interaction is that they are much less sensitive to the one-electron atomic basis compared to the case of the standard Coulomb interaction. Here, we provide a detailed study of the basis convergence of range-separated density-functional theory. We study the convergence of the partial-wave expansion of the long-range wave function near the electron-electron coalescence. We show that the rate of convergence is exponential with respect to the maximal angular momentum L for the long-range wave function, whereas it is polynomial for the case of the Coulomb interaction. We also study the convergence of the long-range second-order Møller-Plesset correlation energy of four systems (He, Ne, N2, and H2O) with cardinal number X of the Dunning basis sets cc - p(C)V XZ and find that the error in the correlation energy is best fitted by an exponential in X. This leads us to propose a three-point complete-basis-set extrapolation scheme for range-separated density-functional theory based on an exponential formula.
NASA Astrophysics Data System (ADS)
Liu, Shuyuan; Zhang, Yong; Feng, Yu; Shi, Changbin; Cao, Yong; Yuan, Wei
2018-02-01
A coupled population balance sectional method (PBSM) coupled with computational fluid dynamics (CFD) is presented to simulate the capture of aerosolized oil droplets (AODs) in a range hood exhaust. The homogeneous nucleation and coagulation processes are modeled and simulated with this CFD-PBSM method. With the design angle, α of the range hood exhaust varying from 60° to 30°, the AODs capture increases meanwhile the pressure drop between the inlet and the outlet of the range hood also increases from 8.38Pa to 175.75Pa. The increasing inlet flow velocities also result in less AODs capture although the total suction increases due to higher flow rates to the range hood. Therefore, the CFD-PBSM method provides an insight into the formation and capture of AODs as well as their impact on the operation and design of the range hood exhaust.
Soliton microcomb range measurement.
Suh, Myoung-Gyun; Vahala, Kerry J
2018-02-23
Laser-based range measurement systems are important in many application areas, including autonomous vehicles, robotics, manufacturing, formation flying of satellites, and basic science. Coherent laser ranging systems using dual-frequency combs provide an unprecedented combination of long range, high precision, and fast update rate. We report dual-comb distance measurement using chip-based soliton microcombs. A single pump laser was used to generate dual-frequency combs within a single microresonator as counterpropagating solitons. We demonstrated time-of-flight measurement with 200-nanometer precision at an averaging time of 500 milliseconds within a range ambiguity of 16 millimeters. Measurements at distances up to 25 meters with much lower precision were also performed. Our chip-based source is an important step toward miniature dual-comb laser ranging systems that are suitable for photonic integration. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Range expansion through fragmented landscapes under a variable climate
Bennie, Jonathan; Hodgson, Jenny A; Lawson, Callum R; Holloway, Crispin TR; Roy, David B; Brereton, Tom; Thomas, Chris D; Wilson, Robert J
2013-01-01
Ecological responses to climate change may depend on complex patterns of variability in weather and local microclimate that overlay global increases in mean temperature. Here, we show that high-resolution temporal and spatial variability in temperature drives the dynamics of range expansion for an exemplar species, the butterfly Hesperia comma. Using fine-resolution (5 m) models of vegetation surface microclimate, we estimate the thermal suitability of 906 habitat patches at the species' range margin for 27 years. Population and metapopulation models that incorporate this dynamic microclimate surface improve predictions of observed annual changes to population density and patch occupancy dynamics during the species' range expansion from 1982 to 2009. Our findings reveal how fine-scale, short-term environmental variability drives rates and patterns of range expansion through spatially localised, intermittent episodes of expansion and contraction. Incorporating dynamic microclimates can thus improve models of species range shifts at spatial and temporal scales relevant to conservation interventions. PMID:23701124
Mismatch between marine plankton range movements and the velocity of climate change
NASA Astrophysics Data System (ADS)
Chivers, William J.; Walne, Anthony W.; Hays, Graeme C.
2017-02-01
The response of marine plankton to climate change is of critical importance to the oceanic food web and fish stocks. We use a 60-year ocean basin-wide data set comprising >148,000 samples to reveal huge differences in range changes associated with climate change across 35 plankton taxa. While the range of dinoflagellates and copepods tended to closely track the velocity of climate change (the rate of isotherm movement), the range of the diatoms moved much more slowly. Differences in range shifts were up to 900 km in a recent warming period, with average velocities of range movement between 7 km per decade northwards for taxa exhibiting niche plasticity and 99 km per decade for taxa exhibiting niche conservatism. The differing responses of taxa to global warming will cause spatial restructuring of the plankton ecosystem with likely consequences for grazing pressures on phytoplankton and hence for biogeochemical cycling, higher trophic levels and biodiversity.
Performance of a GM tube based environmental dose rate monitor operating in the Time-To-Count mode
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zickefoose, J.; Kulkarni, T.; Martinson, T.
The events at the Fukushima Daiichi power plant in the aftermath of a natural disaster underline the importance of a large array of networked environmental monitors to cover areas around nuclear power plants. These monitors should meet a few basic criteria: have a uniform response over a wide range of gamma energies, have a uniform response over a wide range of incident angles, and have a large dynamic range. Many of these criteria are met if the probe is qualified to the international standard IEC 60532 (Radiation protection instrumentation - Installed dose rate meters, warning assemblies and monitors - Xmore » and gamma radiation of energy between 50 keV and 7 MeV), which specifically deals with energy response, angle of incidence, dynamic range, response time, and a number of environmental characteristics. EcoGamma is a dual GM tube environmental gamma radiation monitor designed specifically to meet the requirements of IEC 60532 and operate in the most extreme conditions. EcoGamma utilizes two energy compensated GM tubes operating with a Time-To-Count (TTC) collection algorithm. The TTC algorithm extends the lifetime and range of a GM tube significantly and allows the dual GM tube probe to achieve linearity over approximately 10 decades of gamma dose rate (from the Sv/hr range to 100 Sv/hr). In the TTC mode of operation, the GM tube is not maintained in a biased condition continuously. This is different from a traditional counting system where the GM tube is held at a constant bias continuously and the total number of strikes that the tube registers are counted. The traditional approach allows for good sensitivity, but does not lend itself to a long lifetime of the tube and is susceptible to linearity issues at high count rates. TTC on the other hand only biases the tube for short periods of time and in effect measures the time between events, which is statistically representative of the total strike rate. Since the tube is not continually biased, the life of the tube is extended and the linearity is greatly improved. Testing has been performed at Pacific Northwest National Laboratory (PNNL) in the USA and confirms compliance to IEC 60532 as well as linearity (± 10%) up to 100 Sv/hr. Furthermore, a network of EcoGamma probes may be linked through available supervisory software to provide a dose rate map of an area. This allows for real time monitoring of dose rates from one (or multiple) remote locations. (authors)« less
Application rate affects the degradation rate and hence emissions of chloropicrin in soil.
Ashworth, Daniel J; Yates, Scott R; Stanghellini, Mike; van Wesenbeeck, Ian J
2018-05-01
Increasingly stringent regulations to control soil-air emissions of soil fumigants has led to much research effort aimed at reducing emission potential. Using laboratory soil columns, we aimed to investigate the relationship between chloropicrin (CP) application rate and its emissions from soil across a wide range of CP applications (equivalent to 56-392kgha -1 ). In contrast to the known behavior of other fumigants, total emission percentages were strongly and positively related to application rate (i.e., initial mass), ranging from 4 to 34% across the application rate range. When combined, data from a previous study and the present study showed good overall comparability in terms of CP application rate vs. emission percentage, yielding a second-order polynomial relationship with an R 2 value of 0.93 (n=12). The study revealed that mass losses of CP were strongly disproportional to application rate, also showing a polynomial relationship. Based on degradation studies, we consider that a shorter half-life (faster degradation) at lower application rates limited the amount of CP available for emission. The non-linear relationship between CP application rate and CP emissions (both as % of that applied and as total mass) suggests that low application rates likely lead to disproportionally low emission losses compared with higher application rates; such a relationship could be taken into account when assessing/mitigating risk, e.g., in the setting of buffer zone distances. Copyright © 2017 Elsevier B.V. All rights reserved.
Bacterial aerosol emission rates from municipal wastewater aeration tanks.
Sawyer, B; Elenbogen, G; Rao, K C; O'Brien, P; Zenz, D R; Lue-Hing, C
1993-01-01
In this report we describe the results of a study conducted to determine the rates of bacterial aerosol emission from the surfaces of the aeration tanks of the Metropolitan Water Reclamation District of Greater Chicago John E. Egan Water Reclamation Plant. This study was accomplished by conducting test runs in which Andersen six-stage viable samplers were used to collect bacterial aerosol samples inside a walled tower positioned above an aeration tank liquid surface at the John E. Egan Water Reclamation Plant. The samples were analyzed for standard plate counts (SPC), total coliforms (TC), fecal coliforms, and fecal streptococci. Two methods of calculation were used to estimate the bacterial emission rate. The first method was a conventional stack emission rate calculation method in which the measured air concentration of bacteria was multiplied by the air flow rate emanating from the aeration tanks. The second method was a more empirical method in which an attempt was made to measure all of the bacteria emanating from an isolated area (0.37 m2) of the aeration tank surface over time. The data from six test runs were used to determine bacterial emission rates by both calculation methods. As determined by the conventional calculation method, the average SPC emission rate was 1.61 SPC/m2/s (range, 0.66 to 2.65 SPC/m2/s). As determined by the empirical calculation method, the average SPC emission rate was 2.18 SPC/m2/s (range, 1.25 to 2.66 SPC/m2/s). For TC, the average emission rate was 0.20 TC/m2/s (range, 0.02 to 0.40 TC/m2/s) when the conventional calculation method was used and 0.27 TC/m2/s (range, 0.04 to 0.53 TC/m2/s) when the empirical calculation method was used.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8250547
Hiroi, Satoshi; Morikawa, Saeko; Nakata, Keiko; Maeda, Akiko; Kanno, Tsuneji; Irie, Shin; Ohfuji, Satoko; Hirota, Yoshio; Kase, Tetsuo
2015-01-01
To evaluate antibody response induced by trivalent inactivated influenza vaccine (TIV) against circulating influenza A (H3N2) strains in healthy adults during the 2010/11 and 2011/12 seasons, a hemagglutination-inhibition (HI) assay was utilized to calculate geometric mean antibody titer (GMT), seroprotection rate (post vaccination HI titers of ≥1 :40), and seroresponse rate (4-fold increase in antibody level). In the 2010/11 season, GMT increased 1.8- to 2.0-fold following the first dose of TIV against 3 circulating strains and 2.2-fold following the second compared to before vaccination. The seroresponse rate ranged from 22% to 26% following the first dose of TIV and from 31% to 33% following the second (n = 54 ). The seroprotection rate increased from a range of 6% to 13% to a range of 26% to 33% following the first dose of TIV and to a range of 37% to 42% following the second (n = 54 ). In the 2011/12 season, GMT increased 1.4-fold against A/Osaka/110/2011 and 1.8-fold against A/Osaka/5/2012. For A/Osaka/110/2011, the seroresponse rate was 29%, and the seroprotection rate increased from 26% to 55% following vaccination (n = 31 ). For A/Osaka/5/2012, the seroresponse rate was 26%, and the seroprotection rate increased from 68% to 84% following vaccination (n = 31 ). HI assays with reference antisera demonstrated that the strains in the 2011/12 season were antigenically distinct from vaccine strain (A/Victoria/210/2009). In conclusion, the vaccination increased the seroprotection rate against circulating H3N2 strains in the 2010/11 and 2011/12 seasons. Vaccination of TIV might have potential to induce reactive antibodies against antigenically distinct circulating H3N2 viruses.
Modeling the Declining Positivity Rates for Human Immunodeficiency Virus Testing in New York State.
Martin, Erika G; MacDonald, Roderick H; Smith, Lou C; Gordon, Daniel E; Lu, Tao; OʼConnell, Daniel A
2015-01-01
New York health care providers have experienced declining percentages of positive human immunodeficiency virus (HIV) tests among patients. Furthermore, observed positivity rates are lower than expected on the basis of the national estimate that one-fifth of HIV-infected residents are unaware of their infection. We used mathematical modeling to evaluate whether this decline could be a result of declining numbers of HIV-infected persons who are unaware of their infection, a measure that is impossible to measure directly. A stock-and-flow mathematical model of HIV incidence, testing, and diagnosis was developed. The model includes stocks for uninfected, infected and unaware (in 4 disease stages), and diagnosed individuals. Inputs came from published literature and time series (2006-2009) for estimated new infections, newly diagnosed HIV cases, living diagnosed cases, mortality, and diagnosis rates in New York. Primary model outcomes were the percentage of HIV-infected persons unaware of their infection and the percentage of HIV tests with a positive result (HIV positivity rate). In the base case, the estimated percentage of unaware HIV-infected persons declined from 14.2% in 2006 (range, 11.9%-16.5%) to 11.8% in 2010 (range, 9.9%-13.1%). The HIV positivity rate, assuming testing occurred independent of risk, was 0.12% in 2006 (range, 0.11%-0.15%) and 0.11% in 2010 (range, 0.10%-0.13%). The observed HIV positivity rate was more than 4 times the expected positivity rate based on the model. HIV test positivity is a readily available indicator, but it cannot distinguish causes of underlying changes. Findings suggest that the percentage of unaware HIV-infected New Yorkers is lower than the national estimate and that the observed HIV test positivity rate is greater than expected if infected and uninfected individuals tested at the same rate, indicating that testing efforts are appropriately targeting undiagnosed cases.
Del Bene, Victor A; Arce Rentería, Miguel; Maiman, Moshe; Slugh, Mitch; Gazzola, Deana M; Nadkarni, Siddhartha S; Barr, William B
2017-07-01
The Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) is a self-report instrument, previously shown to differentiate patients with epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES). At present, the odds of MMPI-2-RF scale elevations in PNES patients, as well as the diagnostic predictive value of such scale elevations, remain largely unexplored. This can be of clinical utility, particularly when a diagnosis is uncertain. After looking at mean group differences, we applied contingency table derived odds ratios to a sample of ES (n=92) and PNES (n=77) patients from a video EEG (vEEG) monitoring unit. We also looked at the positive and negative predictive values (PPV, NPV), as well as the false discovery rate (FDR) and false omission rate (FOR) for scales found to have increased odds of elevation in PNES patients. This was completed for the overall sample, as well as the sample stratified by sex. The odds of elevations related to somatic concerns, negative mood, and suicidal ideation in the PNES sample ranged from 2 to 5 times more likely. Female PNES patients had 3-6 times greater odds of such scale elevations, while male PNES patients had odds of 5-15 times more likely. PPV rates ranged from 53.66% to 84.62%, while NPV rates ranged from 47.52% to 90.91%. FDR across scales ranged from 15.38% to 50%, while the FOR ranged from 9.09% to 52.47%. Consistent with prior research, PNES patients have greater odds of MMPI-2-RF scale elevations, particularly related to somatic concerns and mood disturbance. Female PNES patients endorsed greater emotional distress, including endorsement of suicide related items. Elevations of these scales could aid in differentiating PNES from ES patients, although caution is warranted due to the possibility of both false positives and the incorrect omissions of PNES cases. Copyright © 2017 Elsevier Inc. All rights reserved.
Target recognition of log-polar ladar range images using moment invariants
NASA Astrophysics Data System (ADS)
Xia, Wenze; Han, Shaokun; Cao, Jie; Yu, Haoyong
2017-01-01
The ladar range image has received considerable attentions in the automatic target recognition field. However, previous research does not cover target recognition using log-polar ladar range images. Therefore, we construct a target recognition system based on log-polar ladar range images in this paper. In this system combined moment invariants and backpropagation neural network are selected as shape descriptor and shape classifier, respectively. In order to fully analyze the effect of log-polar sampling pattern on recognition result, several comparative experiments based on simulated and real range images are carried out. Eventually, several important conclusions are drawn: (i) if combined moments are computed directly by log-polar range images, translation, rotation and scaling invariant properties of combined moments will be invalid (ii) when object is located in the center of field of view, recognition rate of log-polar range images is less sensitive to the changing of field of view (iii) as object position changes from center to edge of field of view, recognition performance of log-polar range images will decline dramatically (iv) log-polar range images has a better noise robustness than Cartesian range images. Finally, we give a suggestion that it is better to divide field of view into recognition area and searching area in the real application.
Population genetics and the evolution of geographic range limits in an annual plant.
Moeller, David A; Geber, Monica A; Tiffin, Peter
2011-10-01
Abstract Theoretical models of species' geographic range limits have identified both demographic and evolutionary mechanisms that prevent range expansion. Stable range limits have been paradoxical for evolutionary biologists because they represent locations where populations chronically fail to respond to selection. Distinguishing among the proposed causes of species' range limits requires insight into both current and historical population dynamics. The tools of molecular population genetics provide a window into the stability of range limits, historical demography, and rates of gene flow. Here we evaluate alternative range limit models using a multilocus data set based on DNA sequences and microsatellites along with field demographic data from the annual plant Clarkia xantiana ssp. xantiana. Our data suggest that central and peripheral populations have very large historical and current effective population sizes and that there is little evidence for population size changes or bottlenecks associated with colonization in peripheral populations. Whereas range limit populations appear to have been stable, central populations exhibit a signature of population expansion and have contributed asymmetrically to the genetic diversity of peripheral populations via migration. Overall, our results discount strictly demographic models of range limits and more strongly support evolutionary genetic models of range limits, where adaptation is prevented by a lack of genetic variation or maladaptive gene flow.
The wide-range ejector flowmeter: calibrated gas evacuation comprising both high and low gas flows.
Waaben, J; Brinkløv, M M; Jørgensen, S
1984-11-01
The wide-range ejector flowmeter is an active scavenging system applying calibrated gas removal directly to the anaesthetic circuit. The evacuation rate can be adjusted on the flowmeter under visual control using the calibration scale ranging from 200 ml X min-1 to 151 X min-1. The accuracy of the calibration was tested on three ejector flowmeters at 12 different presettings. The percentage deviation from presetting varied from + 18 to - 19.4 per cent. The ejector flowmeter enables the provision of consistent and accurately calibrated extraction of waste gases and is applicable within a wide range of fresh gas flows.
Li-Ion Cells Employing Electrolytes With Methyl Propionate and Ethyl Butyrate Co-Solvents
NASA Technical Reports Server (NTRS)
Smart, Marshall C.; Bugga, Ratnakumar V.
2011-01-01
Future NASA missions aimed at exploring Mars and the outer planets require rechargeable batteries that can operate at low temperatures to satisfy the requirements of such applications as landers, rovers, and penetrators. A number of terrestrial applications, such as hybrid electric vehicles (HEVs) and electric vehicles (EVs) also require energy storage devices that can operate over a wide temperature range (i.e., -40 to +70 C), while still providing high power capability and long life. Currently, the state-of-the-art lithium-ion system has been demonstrated to operate over a wide range of temperatures (-30 to +40 C); however, the rate capability at the lower temperatures is very poor. These limitations at very low temperatures are due to poor electrolyte conductivity, poor lithium intercalation kinetics over the electrode surface layers, and poor ionic diffusion in the electrode bulk. Two wide-operating-temperature-range electrolytes have been developed based on advances involving lithium hexafluorophosphate-based solutions in carbonate and carbonate + ester solvent blends, which have been further optimized in the context of the technology and targeted applications. The approaches employed include further optimization of electrolytes containing methyl propionate (MP) and ethyl butyrate (EB), which are effective co-solvents, to widen the operating temperature range beyond the baseline systems. Attention was focused on further optimizing ester-based electrolyte formulations that have exhibited the best performance at temperatures ranging from -60 to +60 C, with an emphasis upon improving the rate capability at -20 to -40 C. This was accomplished by increasing electrolyte salt concentration to 1.20M and increasing the ester content to 60 percent by volume to increase the ionic conductivity at low temperatures. Two JPL-developed electrolytes 1.20M LiPF6 in EC+EMC+MP (20:20:60 v/v %) and 1.20M LiPF6 in EC+EMC+EB (20:20:60 v/v %) operate effectively over a wide temperature range in MCMB-LiNiCoAlO2 and Li4Ti5O12-LiNi-CoAlO2 prototype cells. These electrolytes have enabled high rate performance at low temperature (i.e., up to 2.0C rates at -50 C and 5.0C rates at -40 C), and good cycling performance over a wide temperature range (i.e., from -40 to +70 C). Current efforts are focused upon improving the high temperature resilience of the methyl propionatebased system through the use of electrolyte additives, which are envisioned to improve the nature of the solid electrolyte interphase (SEI) layers.
Home Range and Ranging Behaviour of Bornean Elephant (Elephas maximus borneensis) Females
Alfred, Raymond; Ahmad, Abd Hamid; Payne, Junaidi; Williams, Christy; Ambu, Laurentius Nayan; How, Phua Mui; Goossens, Benoit
2012-01-01
Background Home range is defined as the extent and location of the area covered annually by a wild animal in its natural habitat. Studies of African and Indian elephants in landscapes of largely open habitats have indicated that the sizes of the home range are determined not only by the food supplies and seasonal changes, but also by numerous other factors including availability of water sources, habitat loss and the existence of man-made barriers. The home range size for the Bornean elephant had never been investigated before. Methodology/Principal Findings The first satellite tracking program to investigate the movement of wild Bornean elephants in Sabah was initiated in 2005. Five adult female elephants were immobilized and neck collars were fitted with tracking devices. The sizes of their home range and movement patterns were determined using location data gathered from a satellite tracking system and analyzed by using the Minimum Convex Polygon and Harmonic Mean methods. Home range size was estimated to be 250 to 400 km2 in a non-fragmented forest and 600 km2 in a fragmented forest. The ranging behavior was influenced by the size of the natural forest habitat and the availability of permanent water sources. The movement pattern was influenced by human disturbance and the need to move from one feeding site to another. Conclusions/Significance Home range and movement rate were influenced by the degree of habitat fragmentation. Once habitat was cleared or converted, the availability of food plants and water sources were reduced, forcing the elephants to travel to adjacent forest areas. Therefore movement rate in fragmented forest was higher than in the non-fragmented forest. Finally, in fragmented habitat human and elephant conflict occurrences were likely to be higher, due to increased movement bringing elephants into contact more often with humans. PMID:22347469
Kitai, Yuichiro; Doi, Yohei; Osaki, Keisuke; Sugioka, Sayaka; Koshikawa, Masao; Sugawara, Akira
2015-12-01
Proteinuria is an established risk factor for progression of renal disease, including diabetic nephropathy. The predictive power of proteinuria, especially nephrotic range proteinuria, for progressive renal deterioration has been well demonstrated in diabetic patients with normal to relatively preserved renal function. However, little is known about the relationship between severity of proteinuria and renal outcome in pre-dialysis diabetic patients with severely impaired renal function. 125 incident dialysis patients with type 2 diabetes were identified. This study was aimed at retrospectively evaluating the impact of nephrotic range proteinuria (urinary protein-creatinine ratio above 3.5 g/gCr) on renal function decline during the 3 months just prior to dialysis initiation. In total, 103 patients (82.4 %) had nephrotic range proteinuria. The median rate of decline in estimated glomerular filtration rate (eGFR) in this study population was 0.98 (interquartile range 0.51-1.46) ml/min/1.73 m(2) per month. Compared to patients without nephrotic range proteinuria, patients with nephrotic range proteinuria showed significantly faster renal function decline (0.46 [0.24-1.25] versus 1.07 [0.64-1.54] ml/min/1.73 m(2) per month; p = 0.007). After adjusting for gender, age, systolic blood pressure, serum albumin, calcium-phosphorus product, hemoglobin A1c, and use of an angiotensin-converting enzyme inhibitor or an angiotensin II receptor blocker, patients with nephrotic range proteinuria showed a 3.89-fold (95 % CI 1.08-14.5) increased risk for rapid renal function decline defined as a decline in eGFR ≥0.5 ml/min/1.73 m(2) per month. Nephrotic range proteinuria is the predominant renal risk factor in type 2 diabetic patients with severely impaired renal function receiving pre-dialysis care.
NASA Technical Reports Server (NTRS)
Knapp, C. F.; Evans, J. M.; Grande, K. J.; Murphy, C. D.; Patwardhan, A. R.
1992-01-01
Changes in autonomic outflow to peripheral organs during the development of bedrest induced orthostatic intolerance have not been determined. Recent studies have indicated that spectral analysis provides an indirect assessment of these changes. Eight male subjects were studied before and after 22 hours of 6 degree head down bedrest plus Lasix (40 mg. P.P.). Cardiovascular spectra (using an autoregressive technique) were determined for heart rate (HR, ECG), arterial pressure (AP, Finapres), radial artery flow (RF, Hokansen) and respiration rate (RR, BoMed). Spectra were obtained from 2.5 minute segments during control, lower body negative pressure (minus 10, 20, 30, 40, 50 mmHg) and recovery. Bedrest increased HR spectra power in the low frequency (.001 to .041 Hz) range, increased RF power in the low and mid (.04 to .18 Hz) range and increased AP power in the high (.18 to .50 Hz) frequency range. Increasing levels of lower body negative pressure decreased HR power and increased RF power in the high frequency range and decreased AP power in the low frequency range. Since spectral power of HR in the high frequency range has been shown to indicate parasympathetically mediated regulation and power in the low and mid frequency ranges indicates a sympathetic / parasympathetic mixture, then both bedrest and lower body negative pressure appeared to shift sympathetic / parasympathetic balance toward sympathetic regulation of HR. The interpretation of the spectral content of AP and RF with respect to their autonomic origins remains unclear.
Success rates of a skeletal anchorage system in orthodontics: A retrospective analysis.
Lam, Raymond; Goonewardene, Mithran S; Allan, Brent P; Sugawara, Junji
2018-01-01
To evaluate the premise that skeletal anchorage with SAS miniplates are highly successful and predictable for a range of complex orthodontic movements. This retrospective cross-sectional analysis consisted of 421 bone plates placed by one clinician in 163 patients (95 female, 68 male, mean age 29.4 years ± 12.02). Simple descriptive statistics were performed for a wide range of malocclusions and desired movements to obtain success, complication, and failure rates. The success rate of skeletal anchorage system miniplates was 98.6%, where approximately 40% of cases experienced mild complications. The most common complication was soft tissue inflammation, which was amenable to focused oral hygiene and antiseptic rinses. Infection occurred in approximately 15% of patients where there was a statistically significant correlation with poor oral hygiene. The most common movements were distalization and intrusion of teeth. More than a third of the cases involved complex movements in more than one plane of space. The success rate of skeletal anchorage system miniplates is high and predictable for a wide range of complex orthodontic movements.
NASA Astrophysics Data System (ADS)
Gary, S. Peter; Zhao, Yinjian; Hughes, R. Scott; Wang, Joseph; Parashar, Tulasi N.
2018-06-01
Three-dimensional particle-in-cell simulations of the forward cascade of decaying turbulence in the relatively short-wavelength kinetic range have been carried out as initial-value problems on collisionless, homogeneous, magnetized electron-ion plasma models. The simulations have addressed both whistler turbulence at β i = β e = 0.25 and kinetic Alfvén turbulence at β i = β e = 0.50, computing the species energy dissipation rates as well as the increase of the Boltzmann entropies for both ions and electrons as functions of the initial dimensionless fluctuating magnetic field energy density ε o in the range 0 ≤ ε o ≤ 0.50. This study shows that electron and ion entropies display similar rates of increase and that all four entropy rates increase approximately as ε o , consistent with the assumption that the quasilinear premise is valid for the initial conditions assumed for these simulations. The simulations further predict that the time rates of ion entropy increase should be substantially greater for kinetic Alfvén turbulence than for whistler turbulence.
Hatch, Christine E; Fisher, Andrew T.; Revenaugh, Justin S.; Constantz, Jim; Ruehl, Chris
2006-01-01
We present a method for determining streambed seepage rates using time series thermal data. The new method is based on quantifying changes in phase and amplitude of temperature variations between pairs of subsurface sensors. For a reasonable range of streambed thermal properties and sensor spacings the time series method should allow reliable estimation of seepage rates for a range of at least ±10 m d−1 (±1.2 × 10−2 m s−1), with amplitude variations being most sensitive at low flow rates and phase variations retaining sensitivity out to much higher rates. Compared to forward modeling, the new method requires less observational data and less setup and data handling and is faster, particularly when interpreting many long data sets. The time series method is insensitive to streambed scour and sedimentation, which allows for application under a wide range of flow conditions and allows time series estimation of variable streambed hydraulic conductivity. This new approach should facilitate wider use of thermal methods and improve understanding of the complex spatial and temporal dynamics of surface water–groundwater interactions.
Shoreline erosion rates along barrier islands of the north central gulf of Mexico
NASA Astrophysics Data System (ADS)
Shabica, Stephen V.; Dolan, Robert; May, Suzette; May, Paul
1983-09-01
Rates of shoreline change and overwash penetration distances were calculated for barrier islands along the Louisiana, Mississippi, and Alabama coasts with the orthogonal grid mapping system (OGMS). Average rates of shoreline change are exceptionally high in Louisiana, being of the order -4.7 to -7.4 m yr-1. Mississippi and Alabama recession rates are lower and range from -2.0 to -3.1 m yr-1 over the period of record. Erosion rates along the shorelines of these islands have remained relatively constant over the period of study with five exceptions in coastal Louisiana and the Chandeleur-Breton Islands Arc, and two exceptions along the Mississippi-Alabama barrier islands where they have accelerated. Mean overwash penetration is greatest along Dauphin Island, Alabama, and Cat Island, Mississippi: 207.6 and 197.9 m, respectively. The Chandeleur-Brenton Islands Arc range from 88.1 m at the central barrier to 180.4 along the flanks. The Mississippi islands range from 105.2 m on Ship Island to 200.5 m along central Horn Island. Mean overwash penetration along the Louisiana barriers is highly variable: 46.3 to 211.4 m.
Optimum moisture levels for biodegradation of mortality composting envelope materials.
Ahn, H K; Richard, T L; Glanville, T D
2008-01-01
Moisture affects the physical and biological properties of compost and other solid-state fermentation matrices. Aerobic microbial systems experience different respiration rates (oxygen uptake and CO2 evolution) as a function of moisture content and material type. In this study the microbial respiration rates of 12 mortality composting envelope materials were measured by a pressure sensor method at six different moisture levels. A wide range of respiration (1.6-94.2mg O2/g VS-day) rates were observed for different materials, with alfalfa hay, silage, oat straw, and turkey litter having the highest values. These four envelope materials may be particularly suitable for improving internal temperature and pathogen destruction rates for disease-related mortality composting. Optimum moisture content was determined based on measurements across a range that spans the maximum respiration rate. The optimum moisture content of each material was observed near water holding capacity, which ranged from near 60% to over 80% on a wet basis for all materials except a highly stabilized soil compost blend (optimum around 25% w.b.). The implications of the results for moisture management and process control strategies during mortality composting are discussed.
NASA Astrophysics Data System (ADS)
Abed, Farid H.
2010-11-01
A constitutive relation is presented in this paper to describe the plastic behavior of ferritic steel over a broad range of temperatures and strain rates. The thermo-mechanical behavior of high strength low alloy (HSLA-65) and DH-63 naval structural steels is considered in this study at strains over 40%. The temperatures and strain rates are considered in the range where dynamic strain aging is not effective. The concept of thermal activation analysis as well as the dislocation interaction mechanism is used in developing the flow model for both the isothermal and adiabatic viscoplastic deformation. The flow stresses of the two steels are very sensitive to temperature and strain rate, the yield stresses increase with decreasing temperatures and increasing strain rates. That is, the thermal flow stress is mainly captured by the yield stresses while the hardening stresses are totally pertained to the athermal component of the flow stress. The proposed constitutive model predicts results that compare very well with the measured ones at initial temperature range of 77 K to 1000 K and strain rates between 0.001 s-1 and 8500 s-1 for both steels.
Servais, P
1995-03-01
In aquatic ecosystems, [(3)H]thymidine incorporation into bacterial DNA and [(3)H]leucine incorporation into proteins are usually used to estimate bacterial production. The incorporation rates of four amino acids (leucine, tyrosine, lysine, alanine) into proteins of bacteria were measured in parallel on natural freshwater samples from the basin of the river Meuse (Belgium). Comparison of the incorporation into proteins and into the total macromolecular fraction showed that these different amino acids were incorporated at more than 90% into proteins. From incorporation measurements at four subsaturated concentrations (range, 2-77 nm), the maximum incorporation rates were determined. Strong correlations (r > 0.91 for all the calculated correlations) were found between the maximum incorporation rates of the different tested amino acids over a range of two orders of magnitude of bacterial activity. Bacterial production estimates were calculated using theoretical and experimental conversion factors. The productions calculated from the incorporation rates of the four amino acids were in good concordance, especially when the experimental conversion factors were used (slope range, 0.91-1.11, and r > 0.91). This study suggests that the incorporation of various amino acids into proteins can be used to estimate bacterial production.
On the communicative significance of whistles in wild killer whales (Orcinus orca)
NASA Astrophysics Data System (ADS)
Thomsen, Frank; Franck, Dierk; Ford, John
2002-08-01
Killer whales (Orcinus orca) use pulsed calls and whistles in underwater communication. Unlike pulsed calls, whistles have received little study and thus their function is poorly known. In this study, whistle activities of groups of individually known killer whales were compared quantitatively across behavioural categories. Acoustic recordings and simultaneous behavioural observations were made of northern resident killer whales off Vancouver Island in 1996 and 1997. Whistles were produced at greater rates than discrete calls during close-range behavioural activities than during long-range activities. They were the predominant sound-type recorded during socializing. The number of whistles per animal per minute was significantly higher during close-range behavioural activities than during long-range activities. Evidently, whistles play an important role in the close-range acoustic communication in northern resident killer whales.
On the communicative significance of whistles in wild killer whales (Orcinus orca).
Thomsen, Frank; Franck, Dierk; Ford, John K B
2002-09-01
Killer whales (Orcinus orca) use pulsed calls and whistles in underwater communication. Unlike pulsed calls, whistles have received little study and thus their function is poorly known. In this study, whistle activities of groups of individually known killer whales were compared quantitatively across behavioural categories. Acoustic recordings and simultaneous behavioural observations were made of northern resident killer whales off Vancouver Island in 1996 and 1997. Whistles were produced at greater rates than discrete calls during close-range behavioural activities than during long-range activities. They were the predominant sound-type recorded during socializing. The number of whistles per animal per minute was significantly higher during close-range behavioural activities than during long-range activities. Evidently, whistles play an important role in the close-range acoustic communication in northern resident killer whales.
The Dark Side of Saturn's Gravity
NASA Astrophysics Data System (ADS)
Iess, L.; Racioppa, P.; Durante, D.; Mariani, M., Jr.; Anabtawi, A.; Armstrong, J. W.; Gomez Casajus, L.; Tortora, P.; Zannoni, M.
2017-12-01
On July 19, 2017 the Cassini spacecraft successfully completed its sixth and last pericenter pass devoted to the investigation of Saturn's interior structure and rings. During each pass the spacecraft was tracked for about 24 hours by the antennas of NASA's Deep Space Network and ESA's ESTRACK network, providing high quality measurements of the spacecraft range rate. We report on a preliminary estimate of Saturn's gravity field and ring mass inferred from range rate observables, and discuss the surprising features of our findings.
Kirshenbaum, Eric J; Zhao, Lee C; Myers, Jeremy B; Elliott, Sean P; Vanni, Alex J; Baradaran, Nima; Erickson, Bradley A; Buckley, Jill C; Voelzke, Bryan B; Granieri, Michael A; Summers, Stephen J; Breyer, Benjamin N; Dash, Atreya; Weinberg, Aaron; Alsikafi, Nejd F
2018-05-16
To review a robotic approach to recalcitrant bladder neck obstruction and to assess success and incontinence rates. Patients with a recalcitrant bladder neck contracture or vesicourethral anastomotic stenosis who underwent robotic bladder neck reconstruction (RBNR) were identified. We reviewed patient demographics, medical history, etiology, previous endoscopic management, cystoscopic and symptomatic outcomes, urinary continence, and complications. Stricture success was anatomic and functional based upon atraumatic passage of a 17 Fr flexible cystoscope or uroflowmetry rate >15 ml/s. Incontinence was defined as the use of >1 pad per day or procedures for incontinence. Between 2015 and 2017, 12 patients were identified who met study criteria and underwent RBNR. Etiology of obstruction was endoscopic prostate procedure in 7 and radical prostatectomy in 5. The mean operative time was 216 minutes (range 120-390 minutes), with a mean estimated blood loss of 85 cc (range 5-200 cc). Median length of stay was 1 day (range 1-5 days). Three of 12 patients had recurrence of obstruction for a 75% success rate. Additionally, 82% of patients without preoperative incontinence were continent with a median follow-up of 13.5 months (range 5-30 months). There was 1 Clavien IIIb complication of osteitis pubis and pubovesical fistula that required vesicopubic fistula repair with pubic bone debridement. RBNR is a viable surgical option with high patency rates and favorable continence outcomes. This is in contrast to perineal reconstruction, which has high incontinence rates. If future incontinence procedures are needed, outcomes may be improved given lack of previous perineal dissection. Copyright © 2018 Elsevier Inc. All rights reserved.
The fate of chlorinated aliphatics in anaerobic treatment under transient loading
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chiu, Y.C.
1993-01-01
A CSTR with dispersed-growth anaerobic bacteria that simultaneously remove COD and chlorinated aliphatics was used. Seven chlorinated aliphatics (methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, 1,1-dichloroethylene, trichloroethylene, and tetrachloroethylene) were biotransformed into lower-chlorinated compounds by anaerobic treatment, utilizing propionic acid (HPr) or acetic acid (HAc). The microorganisms supplied with HAc grew and were sustained at higher BSS concentrations (4,500 to 11,000 mg/L) than those with HPr (2,000 to 5,000 mg/L). The anaerobic treatment process has a considerable potential for acclimation to and biotransformation of toxic chlorinated aliphatics. For providing a safe operation range, the maximum loading rates of the chlorinated aliphaticsmore » are defined as the observed daily injection of those compounds which resulted in 50% activity of the biomass. Based on the reactor volume, the maximum chlorinated compound loading rates to the microorganisms metabolizing HPr were from 0.4 to 90 mg/L-day, while the rates ranged from 0.6 to 190 mg/L-day for the microorganisms metabolizing HAc. When based on biomass, the maximum loading rates of the microorganisms metabolizing HPr were from 0.2 to 26 mg/g cell-day, while rates for the microorganisms metabolizing HAc ranged from 0.1 to 19 mg/g cell-day. Anaerobic microorganisms have higher resistance to chlorinated aliphatic alkenes than alkanes, and can biotransform about 0.04 to 68 pound chlorinated aliphatics while simultaneously metabolizing 1,000 pounds COD. Therefore, within the safe operation range, the anaerobic process can stabilize organic pollution at a high rate while still biotransforming chlorinated aliphatics.« less
Carpio, B; Brown, B
1993-01-01
The undergraduate nursing degree program (B.Sc.N.) at McMaster University School of Nursing uses small groups, and is learner-centered and problem-based. A study was conducted during the 1991 admissions cycle to determine the initial reliability and validity of the semi-structured personal interview which constitutes the final component of candidate selection for this program. During the interview, three-member teams assess applicant suitability to the program based on six dimensions: applicant motivation, awareness of the program, problem-solving abilities, ability to relate to others, self-appraisal skills, and career goals. Each interviewer assigns the applicant a global rating using a seven-point scale. For the purposes of this study four interviewer teams were randomly selected from the pool of 31 teams to interview four simulated (preprogrammed) applicants. Using two-factor repeated-measures ANOVA to analyze interview ratings, inter-rater and inter-team intraclass correlation coefficients (ICC) were calculated. Inter-team reliability ranged from .64 to .97 for the individual dimensions, and .66 to .89 on global ratings. Inter-rater ICC for the six dimensions ranged from .81 to .99, and .96 to .99 for the global ratings. The item-to-total correlation coefficients between individual dimensions and global ratings ranged from .8 to 1.0. Pearson correlations between items ranged from .77 to 1.0. The ICC were then calculated for the interview scores of 108 actual applicants to the program. Inter-rater reliability based on global ratings was .79 for the single (1 rater) observation, and .91 for the multiple (3 rater) observation. These findings support the continued use of the interview as a reliable instrument with face validity. Studies of predictive validity will be undertaken.
Spall response of single-crystal copper
NASA Astrophysics Data System (ADS)
Turley, W. D.; Fensin, S. J.; Hixson, R. S.; Jones, D. R.; La Lone, B. M.; Stevens, G. D.; Thomas, S. A.; Veeser, L. R.
2018-02-01
We performed a series of systematic spall experiments on single-crystal copper in an effort to determine and isolate the effects of crystal orientation, peak stress, and unloading strain rate on the tensile spall strength. Strain rates ranging from 0.62 to 2.2 × 106 s-1 and peak shock stresses in the 5-14 GPa range, with one additional experiment near 50 GPa, were explored as part of this work. Gun-driven impactors, called flyer plates, generated flat top shocks followed by spall. This work highlights the effect of crystal anisotropy on the spall strength by showing that the spall strength decreases in the following order: [100], [110], and [111]. Over the range of stresses and strain rates explored, the spall strength of [100] copper depends strongly on both the strain rate and shock stress. Except at the very highest shock stress, the results for the [100] orientation show linear relationships between the spall strength and both the applied compressive stress and the strain rate. In addition, hydrodynamic computer code simulations of the spall experiments were performed to calculate the relationship between the strain rate near the spall plane in the target and the rate of free surface velocity release during the pullback. As expected, strain rates at the spall plane are much higher than the strain rates estimated from the free surface velocity release rate. We have begun soft recovery experiments and molecular dynamics calculations to understand the unusual recompression observed in the spall signature for [100] crystals.
NASA Astrophysics Data System (ADS)
Abadie, J.; Abbott, B. P.; Abbott, R.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Ajith, P.; Allen, B.; Allen, G.; Amador Ceron, E.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Antonucci, F.; Aoudia, S.; Arain, M. A.; Araya, M.; Aronsson, M.; Arun, K. G.; Aso, Y.; Aston, S.; Astone, P.; Atkinson, D. E.; Aufmuth, P.; Aulbert, C.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barker, D.; Barnum, S.; Barone, F.; Barr, B.; Barriga, P.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Bauchrowitz, J.; Bauer, Th S.; Behnke, B.; Beker, M. G.; Belczynski, K.; Benacquista, M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bigotta, S.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birindelli, S.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Blomberg, A.; Boccara, C.; Bock, O.; Bodiya, T. P.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bork, R.; Born, M.; Bose, S.; Bosi, L.; Boyle, M.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Brau, J. E.; Breyer, J.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Budzyński, R.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Buskulic, D.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campagna, E.; Campsie, P.; Cannizzo, J.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C.; Carbognani, F.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarini, E.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chassande Mottin, E.; Chelkowski, S.; Chen, Y.; Chincarini, A.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Clark, D.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, R.; Cook, D.; Corbitt, T. R.; Corda, C.; Cornish, N.; Corsi, A.; Costa, C. A.; Coulon, J. P.; Coward, D.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Culter, R. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dari, A.; Das, K.; Dattilo, V.; Daudert, B.; Davier, M.; Davies, G.; Davis, A.; Daw, E. J.; Day, R.; Dayanga, T.; De Rosa, R.; DeBra, D.; Degallaix, J.; del Prete, M.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Devanka, P.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Emilio, M. Di Paolo; Di Virgilio, A.; Díaz, M.; Dietz, A.; Donovan, F.; Dooley, K. L.; Doomes, E. E.; Dorsher, S.; Douglas, E. S. D.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Dueck, J.; Dumas, J. C.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Engel, R.; Etzel, T.; Evans, M.; Evans, T.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Flaminio, R.; Flanigan, M.; Flasch, K.; Foley, S.; Forrest, C.; Forsi, E.; Fotopoulos, N.; Fournier, J. D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gammaitoni, L.; Garofoli, J. A.; Garufi, F.; Gemme, G.; Genin, E.; Gennai, A.; Gholami, I.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gill, C.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Gustafson, E. K.; Gustafson, R.; Hage, B.; Hall, P.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Haughian, K.; Hayama, K.; Heefner, J.; Heitmann, H.; Hello, P.; Heng, I. S.; Heptonstall, A.; Hewitson, M.; Hild, S.; Hirose, E.; Hoak, D.; Hodge, K. A.; Holt, K.; Hosken, D. J.; Hough, J.; Howell, E.; Hoyland, D.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Jaranowski, P.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.; Kanner, J.; Katsavounidis, E.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, C.; Kim, H.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kondrashov, V.; Kopparapu, R.; Koranda, S.; Kowalska, I.; Kozak, D.; Krause, T.; Kringel, V.; Krishnamurthy, S.; Krishnan, B.; Królak, A.; Kuehn, G.; Kullman, J.; Kumar, R.; Kwee, P.; Landry, M.; Lang, M.; Lantz, B.; Lastzka, N.; Lazzarini, A.; Leaci, P.; Leong, J.; Leonor, I.; Leroy, N.; Letendre, N.; Li, J.; Li, T. G. F.; Lin, H.; Lindquist, P. E.; Lockerbie, N. A.; Lodhia, D.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lu, P.; Luan, J.; Lubiński, M.; Lucianetti, A.; Lück, H.; Lundgren, A.; Machenschalk, B.; MacInnis, M.; Mackowski, J. M.; Mageswaran, M.; Mailand, K.; Majorana, E.; Mak, C.; Man, N.; Mandel, I.; Mandic, V.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Maros, E.; Marque, J.; Martelli, F.; Martin, I. W.; Martin, R. M.; Marx, J. N.; Mason, K.; Masserot, A.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McIntyre, G.; McIvor, G.; McKechan, D. J. A.; Meadors, G.; Mehmet, M.; Meier, T.; Melatos, A.; Melissinos, A. C.; Mendell, G.; Menéndez, D. F.; Mercer, R. A.; Merill, L.; Meshkov, S.; Messenger, C.; Meyer, M. S.; Miao, H.; Michel, C.; Milano, L.; Miller, J.; Minenkov, Y.; Mino, Y.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moe, B.; Mohan, M.; Mohanty, S. D.; Mohapatra, S. R. P.; Moraru, D.; Moreau, J.; Moreno, G.; Morgado, N.; Morgia, A.; Morioka, T.; Mors, K.; Mosca, S.; Moscatelli, V.; Mossavi, K.; Mours, B.; MowLowry, C.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Müller-Ebhardt, H.; Munch, J.; Murray, P. G.; Nash, T.; Nawrodt, R.; Nelson, J.; Neri, I.; Newton, G.; Nishizawa, A.; Nocera, F.; Nolting, D.; Ochsner, E.; O'Dell, J.; Ogin, G. H.; Oldenburg, R. G.; O'Reilly, B.; O'Shaughnessy, R.; Osthelder, C.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Page, A.; Pagliaroli, G.; Palladino, L.; Palomba, C.; Pan, Y.; Pankow, C.; Paoletti, F.; Papa, M. A.; Pardi, S.; Pareja, M.; Parisi, M.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patel, P.; Pedraza, M.; Pekowsky, L.; Penn, S.; Peralta, C.; Perreca, A.; Persichetti, G.; Pichot, M.; Pickenpack, M.; Piergiovanni, F.; Pietka, M.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Plissi, M. V.; Poggiani, R.; Postiglione, F.; Prato, M.; Predoi, V.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Quetschke, V.; Raab, F. J.; Rabaste, O.; Rabeling, D. S.; Radke, T.; Radkins, H.; Raffai, P.; Rakhmanov, M.; Rankins, B.; Rapagnani, P.; Raymond, V.; Re, V.; Reed, C. M.; Reed, T.; Regimbau, T.; Reid, S.; Reitze, D. H.; Ricci, F.; Riesen, R.; Riles, K.; Roberts, P.; Robertson, N. A.; Robinet, F.; Robinson, C.; Robinson, E. L.; Rocchi, A.; Roddy, S.; Röver, C.; Rogstad, S.; Rolland, L.; Rollins, J.; Romano, J. D.; Romano, R.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sakata, S.; Sakosky, M.; Salemi, F.; Sammut, L.; Sancho de la Jordana, L.; Sandberg, V.; Sannibale, V.; Santamaría, L.; Santostasi, G.; Saraf, S.; Sassolas, B.; Sathyaprakash, B. S.; Sato, S.; Satterthwaite, M.; Saulson, P. R.; Savage, R.; Schilling, R.; Schnabel, R.; Schofield, R.; Schulz, B.; Schutz, B. F.; Schwinberg, P.; Scott, J.; Scott, S. M.; Searle, A. C.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sergeev, A.; Shaddock, D. A.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Siemens, X.; Sigg, D.; Singer, A.; Sintes, A. M.; Skelton, G.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, M. R.; Smith, N. D.; Somiya, K.; Sorazu, B.; Speirits, F. C.; Stein, A. J.; Stein, L. C.; Steinlechner, S.; Steplewski, S.; Stochino, A.; Stone, R.; Strain, K. A.; Strigin, S.; Stroeer, A.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sung, M.; Susmithan, S.; Sutton, P. J.; Swinkels, B.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, J. R.; Taylor, R.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Thüring, A.; Titsler, C.; Tokmakov, K. V.; Toncelli, A.; Tonelli, M.; Torres, C.; Torrie, C. I.; Tournefier, E.; Travasso, F.; Traylor, G.; Trias, M.; Trummer, J.; Tseng, K.; Ugolini, D.; Urbanek, K.; Vahlbruch, H.; Vaishnav, B.; Vajente, G.; Vallisneri, M.; van den Brand, J. F. J.; Van Den Broeck, C.; van der Putten, S.; van der Sluys, M. V.; van Veggel, A. A.; Vass, S.; Vaulin, R.; Vavoulidis, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Veltkamp, C.; Verkindt, D.; Vetrano, F.; Viceré, A.; Villar, A.; Vinet, J.-Y.; Vocca, H.; Vorvick, C.; Vyachanin, S. P.; Waldman, S. J.; Wallace, L.; Wanner, A.; Ward, R. L.; Was, M.; Wei, P.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wen, S.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D. J.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, L.; Willke, B.; Winkelmann, L.; Winkler, W.; Wipf, C. C.; Wiseman, A. G.; Woan, G.; Wooley, R.; Worden, J.; Yakushin, I.; Yamamoto, H.; Yamamoto, K.; Yeaton-Massey, D.; Yoshida, S.; Yu, P. P.; Yvert, M.; Zanolin, M.; Zhang, L.; Zhang, Z.; Zhao, C.; Zotov, N.; Zucker, M. E.; Zweizig, J.; LIGO Scientific Collaboration; Virgo Collaboration
2010-09-01
We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. The most confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr-1 per Milky Way Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 Myr-1 MWEG-1 to 1000 Myr-1 MWEG-1 (Kalogera et al 2004 Astrophys. J. 601 L179; Kalogera et al 2004 Astrophys. J. 614 L137 (erratum)). We convert coalescence rates into detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and projected sensitivities for our advanced detectors. Using the detector sensitivities derived from these data, we find a likely detection rate of 0.02 per year for Initial LIGO-Virgo interferometers, with a plausible range between 2 × 10-4 and 0.2 per year. The likely binary neutron-star detection rate for the Advanced LIGO-Virgo network increases to 40 events per year, with a range between 0.4 and 400 per year.
A new variable interval schedule with constant hazard rate and finite time range.
Bugallo, Mehdi; Machado, Armando; Vasconcelos, Marco
2018-05-27
We propose a new variable interval (VI) schedule that achieves constant probability of reinforcement in time while using a bounded range of intervals. By sampling each trial duration from a uniform distribution ranging from 0 to 2 T seconds, and then applying a reinforcement rule that depends linearly on trial duration, the schedule alternates reinforced and unreinforced trials, each less than 2 T seconds, while preserving a constant hazard function. © 2018 Society for the Experimental Analysis of Behavior.
Deep Throttle Turbopump Technology Testing
NASA Technical Reports Server (NTRS)
Ferguson, T. V.; Guinzburg, A.; McGlynn, R. D.; Williams, M.
2002-01-01
The objectives of this viewgraph presentation were to: (1) enhance and demonstrate critical technologies in support of planned RBCC flight test programs; and (2) obtain knowledge of wide flow range as it is applicable to liquid rocket engine turbopumps operating over extreme throttle ranges. This program was set up to demonstrate wide flow range diffuser technologies. The testing phase of the contract to provide data to anchor initial designs was partially successful. Data collected suggest flow phenomena exists at off-design flow rates.
"Stillbirth rates in 20 countries of Latin America: an ecological study".
Pingray, Veronica; Althabe, Fernando; Vazquez, Paula; Correa, Malena; Pajuelo, Mónica; Belizán, José M
2018-05-23
To describe country-level stillbirth rates and their change over time in Latin America, and to measure the association of stillbirth rates with socioeconomic and health coverage indicators in the region. Ecological study. 20 countries of Latin America. Aggregated data from pregnant women with countries as units of analysis. We used stillbirth estimates, and socioeconomic and health care coverage indicators reported from 2006 to 2016 from UNICEF, United Nations Development Programme and World Bank datasets. We calculated Spearman's correlation coefficients between stillbirths rates and socioeconomic and health coverage indicators. National estimates of stillbirth rates in each country. The estimated stillbirth rate for Latin America for 2015 was 8.1 per 1000 births (range 3.1-24.9). Seven Latin America countries had rates higher than 10 stillbirths per 1000 births. The average annual reduction rate for the region was 2% (range 0.1-3.8%), with the majority of Latin America countries ranging between 1.5 and 2.5%. National stillbirth rates were correlated to: women's schooling (rS=-0.7910), gross domestic product per capita (rS=-0.8226), fertility rate (rS=0.6055), urban population (rS=-0.6316) and deliveries at health facilities (rS=-0.6454). Country-level estimated stillbirth rates in Latin America varied widely in 2015. The trend and magnitude of reduction in stillbirth rates between 2000 and 2015 was similar to the world average. Socioeconomic and health coverage indicators were correlated to stillbirth rates in Latin America. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Prentice, C.S.; Weber, J.C.; Crosby, C.J.; Ragona, D.
2010-01-01
Recent geodetic studies suggest that the Central Range fault is the principal plate-boundary structure accommodating strike-slip motion between the Caribbean and South American plates. Our study shows that the fault forms a topographically prominent lineament in central Trinidad. Results from a paleoseismic investigation at a site where Holocene sediments have been deposited across the Central Range fault indicate that it ruptured the ground surface most recently between 2710 and 550 yr B.P. If the geodetic slip rate of 9-15 mm/yr is representative of Holocene slip rates, our paleoseismic data suggest that at least 4.9 m of potential slip may have accumulated on the fault and could be released during a future large earthquake (M > 7). ?? 2010 Geological Society of America.
NASA Astrophysics Data System (ADS)
Sarkar, A.; Chakravartty, J. K.
2013-10-01
A model is developed to predict the constitutive flow behavior of cadmium during compression test using artificial neural network (ANN). The inputs of the neural network are strain, strain rate, and temperature, whereas flow stress is the output. Experimental data obtained from compression tests in the temperature range -30 to 70 °C, strain range 0.1 to 0.6, and strain rate range 10-3 to 1 s-1 are employed to develop the model. A three-layer feed-forward ANN is trained with Levenberg-Marquardt training algorithm. It has been shown that the developed ANN model can efficiently and accurately predict the deformation behavior of cadmium. This trained network could predict the flow stress better than a constitutive equation of the type.
Correcting reaction rates measured by saturation-transfer magnetic resonance spectroscopy
NASA Astrophysics Data System (ADS)
Gabr, Refaat E.; Weiss, Robert G.; Bottomley, Paul A.
2008-04-01
Off-resonance or spillover irradiation and incomplete saturation can introduce significant errors in the estimates of chemical rate constants measured by saturation-transfer magnetic resonance spectroscopy (MRS). Existing methods of correction are effective only over a limited parameter range. Here, a general approach of numerically solving the Bloch-McConnell equations to calculate exchange rates, relaxation times and concentrations for the saturation-transfer experiment is investigated, but found to require more measurements and higher signal-to-noise ratios than in vivo studies can practically afford. As an alternative, correction formulae for the reaction rate are provided which account for the expected parameter ranges and limited measurements available in vivo. The correction term is a quadratic function of experimental measurements. In computer simulations, the new formulae showed negligible bias and reduced the maximum error in the rate constants by about 3-fold compared to traditional formulae, and the error scatter by about 4-fold, over a wide range of parameters for conventional saturation transfer employing progressive saturation, and for the four-angle saturation-transfer method applied to the creatine kinase (CK) reaction in the human heart at 1.5 T. In normal in vivo spectra affected by spillover, the correction increases the mean calculated forward CK reaction rate by 6-16% over traditional and prior correction formulae.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-05
... choose the duty rates during customs entry procedures that apply to gas and electric kitchen ranges (duty... injet assemblies, vent caps, blowers, valves, gas valves, motors, fans, control boards, light indicator assemblies, timers, light indicators, capacitors, thermistors, sensors, lamps, encoder assemblies, lenses...
Programmable random interval generator
NASA Technical Reports Server (NTRS)
Lindsey, R. S., Jr.
1973-01-01
Random pulse generator can supply constant-amplitude randomly distributed pulses with average rate ranging from a few counts per second to more than one million counts per second. Generator requires no high-voltage power supply or any special thermal cooling apparatus. Device is uniquely versatile and provides wide dynamic range of operation.
A simple analytical infiltration model for short-duration rainfall
NASA Astrophysics Data System (ADS)
Wang, Kaiwen; Yang, Xiaohua; Liu, Xiaomang; Liu, Changming
2017-12-01
Many infiltration models have been proposed to simulate infiltration process. Different initial soil conditions and non-uniform initial water content can lead to infiltration simulation errors, especially for short-duration rainfall (SHR). Few infiltration models are specifically derived to eliminate the errors caused by the complex initial soil conditions. We present a simple analytical infiltration model for SHR infiltration simulation, i.e., Short-duration Infiltration Process model (SHIP model). The infiltration simulated by 5 models (i.e., SHIP (high) model, SHIP (middle) model, SHIP (low) model, Philip model and Parlange model) were compared based on numerical experiments and soil column experiments. In numerical experiments, SHIP (middle) and Parlange models had robust solutions for SHR infiltration simulation of 12 typical soils under different initial soil conditions. The absolute values of percent bias were less than 12% and the values of Nash and Sutcliffe efficiency were greater than 0.83. Additionally, in soil column experiments, infiltration rate fluctuated in a range because of non-uniform initial water content. SHIP (high) and SHIP (low) models can simulate an infiltration range, which successfully covered the fluctuation range of the observed infiltration rate. According to the robustness of solutions and the coverage of fluctuation range of infiltration rate, SHIP model can be integrated into hydrologic models to simulate SHR infiltration process and benefit the flood forecast.
The global decline of cheetah Acinonyx jubatus and what it means for conservation.
Durant, Sarah M; Mitchell, Nicholas; Groom, Rosemary; Pettorelli, Nathalie; Ipavec, Audrey; Jacobson, Andrew P; Woodroffe, Rosie; Böhm, Monika; Hunter, Luke T B; Becker, Matthew S; Broekhuis, Femke; Bashir, Sultana; Andresen, Leah; Aschenborn, Ortwin; Beddiaf, Mohammed; Belbachir, Farid; Belbachir-Bazi, Amel; Berbash, Ali; Brandao de Matos Machado, Iracelma; Breitenmoser, Christine; Chege, Monica; Cilliers, Deon; Davies-Mostert, Harriet; Dickman, Amy J; Ezekiel, Fabiano; Farhadinia, Mohammad S; Funston, Paul; Henschel, Philipp; Horgan, Jane; de Iongh, Hans H; Jowkar, Houman; Klein, Rebecca; Lindsey, Peter Andrew; Marker, Laurie; Marnewick, Kelly; Melzheimer, Joerg; Merkle, Johnathan; M'soka, Jassiel; Msuha, Maurus; O'Neill, Helen; Parker, Megan; Purchase, Gianetta; Sahailou, Samaila; Saidu, Yohanna; Samna, Abdoulkarim; Schmidt-Küntzel, Anne; Selebatso, Eda; Sogbohossou, Etotépé A; Soultan, Alaaeldin; Stone, Emma; van der Meer, Esther; van Vuuren, Rudie; Wykstra, Mary; Young-Overton, Kim
2017-01-17
Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.
Villellas, Jesús; Doak, Daniel F; García, María B; Morris, William F
2015-09-10
Most species are exposed to significant environmental gradients across their ranges, but vital rates (survival, growth, reproduction and recruitment) need not respond in the same direction to those gradients. Opposing vital rate trends across environments, a phenomenon that has been loosely called 'demographic compensation', may allow species to occupy larger geographical ranges and alter their responses to climate change. Yet the term has never been precisely defined, nor has its existence or strength been assessed for multiple species. Here, we provide a rigorous definition, and use it to develop a strong test for demographic compensation. By applying the test to data from 26 published, multi-population demographic studies of plants, we show that demographic compensation commonly occurs. We also investigate the mechanisms by which this phenomenon arises by assessing which demographic processes and life stages are most often involved. In addition, we quantify the effect of demographic compensation on variation in population growth rates across environmental gradients, a potentially important determinant of the size of a species' geographical range. Finally, we discuss the implications of demographic compensation for the responses of single populations and species' ranges to temporal environmental variation and to ongoing environmental trends, e.g. due to climate change. © 2015 John Wiley & Sons Ltd/CNRS.
Koczor, Bálint; Rohonczy, János
2015-01-01
Concerning many former liquid or hybrid liquid/solid NMR consoles, the built in Analog-to-Digital Converters (ADCs) are incapable of digitizing the fids at sampling rates in the MHz range. Regarding both strong anisotropic interactions in the solid state and wide chemical shift dispersion nuclei in solution phase such as (195)Pt, (119)Sn, (207)Pb etc., the spectrum range of interest might be in the MHz range. As determining the informative tensor components of anisotropic NMR interactions requires nonlinear fitting over the whole spectrum including the asymptotic baseline, it is prohibited by low sampling rates of the ADCs. Wide spectrum width is also useful in solution NMR, since windowing of wide chemical shift ranges is avoidable. We built an external analog to digital converter with 10 MHz maximal sampling rate, which can work simultaneously with the built in ADC of the spectrometer. The ADC was tested on both Bruker DRX and Avance-I NMR consoles. In addition to the analog channels it only requires three external digital lines of the NMR console. The ADC sends data to PC via USB. The whole process is controlled by software written in JAVA which is implemented under TopSpin. Copyright © 2015 Elsevier Inc. All rights reserved.
Prevalence of Coccidiosis in Free-Range Chicken in Sidi Thabet, Tunisia.
Kaboudi, Khaled; Umar, Sajid; Munir, Muhammad Tanveer
2016-01-01
Background. Enteric diseases are an important concern to the poultry industry and coccidiosis is imposing a significant economic burden worldwide. Objectives. The main goal of the present study was to investigate the prevalence of coccidiosis in free-range chicken in Sidi Thabet, northeast Tunisia. Methods. Six hundred and thirty free-range chickens along with fecal samples were collected from 15 flocks in this region and two hundred chickens were found positive for oocysts of Eimeria spp. Intestines were dissected and examined for macroscopic lesions. The mucosa of small intestine and the caeca were examined for the presence and identification of parasitic forms using parasitology methods. The mean lesion scores were usually low (<2+) in different intestinal portions of different types of chicken and high scores (>2+) were attributed mainly to the caeca. Results. The overall rate of coccidiosis was 31.8%: E. tenella (61.5%), E. maxima (12%), and E. acervulina (1.5%). Mixed Eimeria species infection was observed with overall prevalence 26.5%. There was a statistically significant difference (P < 0.05) among infection rates, age groups, season, diarrhea, and type of chicken. Conclusion. This is the first report of coccidiosis rate in free-range chicken in this region. Further additional studies are needed to develop better preventive measures against coccidiosis in the country.
Adverse events and dropouts in Alzheimer's disease studies: what can we learn?
Henley, David B; Sundell, Karen L; Sethuraman, Gopalan; Schneider, Lon S
2015-01-01
Interpreting Alzheimer's disease (AD) clinical trial (CT) outcomes is complicated by treatment dropouts and adverse events (AEs). In elderly participants, AE rates, dropouts, and deaths are important considerations as they may undermine the validity of clinical trials. Published discontinuation and safety data are limited. Safety data from 1054 placebo-treated participants in IDENTITY and IDENTITY-2, 76-week, Phase 3 AD studies conducted in 31 countries, were pooled, annualized, and summarized overall, by country and age group. Median age was 74.2 (interquartile range 67.9-79.5) years; 57.4% were female; and median observation time was 63.2 (interquartile range 41.6-77.4) weeks when study drug dosing was halted. Overall annualized rates for discontinuations, discontinuations due to AEs, serious adverse events (SAEs), and deaths were 21.6% (range 19.6%-24.0%), 8.2% (range 8.1%-8.3%), 12.0%, and 1.7%, respectively. AE and discontinuation rates varied by country and age groups. Fall, pneumonia, and atrial fibrillation AEs were more frequent in the oldest age group. These annualized placebo safety data provide insight into the course of enrolled patients with mild-to-moderate AD, and are useful in planning longer term trials and in monitoring safety. Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
The global decline of cheetah Acinonyx jubatus and what it means for conservation
Mitchell, Nicholas; Groom, Rosemary; Pettorelli, Nathalie; Ipavec, Audrey; Jacobson, Andrew P.; Woodroffe, Rosie; Böhm, Monika; Becker, Matthew S.; Broekhuis, Femke; Bashir, Sultana; Andresen, Leah; Aschenborn, Ortwin; Beddiaf, Mohammed; Berbash, Ali; Brandao de Matos Machado, Iracelma; Breitenmoser, Christine; Chege, Monica; Cilliers, Deon; Davies-Mostert, Harriet; Dickman, Amy J.; Ezekiel, Fabiano; Farhadinia, Mohammad S.; Funston, Paul; Henschel, Philipp; Horgan, Jane; de Iongh, Hans H.; Jowkar, Houman; Klein, Rebecca; Lindsey, Peter Andrew; Marker, Laurie; Marnewick, Kelly; Melzheimer, Joerg; Merkle, Johnathan; M'soka, Jassiel; Msuha, Maurus; O'Neill, Helen; Parker, Megan; Purchase, Gianetta; Sahailou, Samaila; Saidu, Yohanna; Samna, Abdoulkarim; Schmidt-Küntzel, Anne; Selebatso, Eda; Sogbohossou, Etotépé A.; Stone, Emma; van der Meer, Esther; van Vuuren, Rudie; Wykstra, Mary; Young-Overton, Kim
2017-01-01
Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human–wildlife coexistence across large multiple-use landscapes. PMID:28028225
Yan, Zejun; Xie, Guohai; Yuan, Hesheng; Cheng, Yue
2015-10-01
To determine the safety and efficacy of modular flexible ureteroscopy and holmium laser lithotripsy for the treatment of renal and proximal ureteral calculi, a retrospective chart review of a single surgeon's 3-year modular flexible ureteroscopy experience was performed. All of the patients were treated with modular flexible ureteroscopy and holmium laser lithotripsy by a single surgeon. Stone-free status was defined as no fragments or a single fragment ≤4 mm in diameter at the 3-month follow-up. The procedure number, operative time, stone-free rates, repeat usage of the multilumen catheter, and perioperative complications were documented. The present study included 215 male patients and 167 female patients, with an average age of 48.5±13.7 years (range, 17-84 years). The mean stone size was 11.5±4.1 mm (range, 4-28 mm), and the mean total stone burden was 17.5±5.7 mm (range 15-46 mm). A total of 305 patients (79.8%) had a stone burden ≤20 mm, and 77 patients (20.2%) had a stone burden >20 mm. The mean number of primary procedures was 1.3±0.2 (range, 1-3). The stone-free rate following the first and the second procedure was 73.4 and 86.9%, respectively. The mean postoperative hospital stay was 3.1±1.2 days (range, 2-6 days). The highest clearance rates were observed for proximal ureteral stones (100%) and renal pelvic stones (88.7%), whereas the lowest clearance rates were observed for lower calyx stones (76.7%) and multiple calyx stones (77.8%). The higher the initial stone burden, the lower the postoperative stone-free rate (≤20 vs. >20 mm; 89.8 vs. 75.3%). The overall complication rate was 8.1%. The results of the present study suggest that modular flexible ureteroscopy with holmium laser lithotripsy may be considered the primary method for the treatment of renal and proximal ureteral calculi in select patients, due to its acceptable efficacy, low morbidity, and relatively low maintenance costs.
[Ribeiro-Technique in Gigantomastia - Review of 294 Reduction Mammaplasties in 8 Years].
Wolter, Andreas; Pluto, Naja; Scholz, Till; Diedrichson, Jens; Arens-Landwehr, Andreas; Liebau, Jutta
2017-12-01
Reduction mammaplasty in patients with gigantomastia is challenging even to very experienced plastic surgeons. Extremely elongated pedicles impair the vascular supply of the nipple-areola complex. Breast shaping and effective reduction are difficult due to the severely stretched skin envelope. The Ribeiro technique is the standard technique for reduction mammaplasty in our clinic. The aim of this study is to review our approach in patients with gigantomastia in comparison to the current literature. From 01/2009 to 12/2016, we performed 1247 reduction mammaplasties in 760 patients. In 294 reduction mammoplasties (23.6 %), resection weight was more than 1000 g per breast corresponding to the definition of gigantomastia. The Ribeiro technique with a superomedial pedicle and inferior dermoglandular flap for autologous augmentation of the upper pole was implemented as standard procedure. In cases with a sternal notch-nipple distance > 40 cm, free nipple grafting was performed. The outcome parameters complication rate, patient satisfaction with the aesthetic result, nipple sensitivity and surgical revision rate were obtained and retrospectively analysed. In 174 patients, 294 reduction mammaplasties were performed with a resection weight of more than 1000 g per breast. Average resection weight was 1389.6 g (range, 1000-4580 g). Average age was 43.5 years (range, 18-76 years), average body mass index (BMI) was 29.2 kg/m 2 (range, 19-40 kg/m 2 ), average sternal notch-nipple distance was 34.8 cm (range, 27-52 cm), average operation time was 117 minutes (range, 72-213 minutes). A free nipple graft was necessary in 30 breasts. Overall complication rate was 7.8 %; secondary surgical revision rate was 16 %. 93 % of the patients were "very satisfied" and "satisfied" with the aesthetic result. Nipple sensitivity was rated "very good" and "good" in 88 %. The Ribeiro technique is a well established, versatile standard technique for reduction mammaplasty, which helps to create high-quality reproducible results with longterm formstable shape. In gigantomastia, this procedure is also very effective to achieve volume reduction and aesthetically pleasing results with a low complication rate. Georg Thieme Verlag KG Stuttgart · New York.
Density of wild prey modulates lynx kill rates on free-ranging domestic sheep.
Odden, John; Nilsen, Erlend B; Linnell, John D C
2013-01-01
Understanding the factors shaping the dynamics of carnivore-livestock conflicts is vital to facilitate large carnivore conservation in multi-use landscapes. We investigated how the density of their main wild prey, roe deer Capreolus capreolus, modulates individual Eurasian lynx Lynx lynx kill rates on free-ranging domestic sheep Ovis aries across a range of sheep and roe deer densities. Lynx kill rates on free-ranging domestic sheep were collected in south-eastern Norway from 1995 to 2011 along a gradient of different livestock and wild prey densities using VHF and GPS telemetry. We used zero-inflated negative binomial (ZINB) models including lynx sex, sheep density and an index of roe deer density as explanatory variables to model observed kill rates on sheep, and ranked the models based on their AICc values. The model including the effects of lynx sex and sheep density in the zero-inflation model and the effect of lynx sex and roe deer density in the negative binomial part received most support. Irrespective of sheep density and sex, we found the lowest sheep kill rates in areas with high densities of roe deer. As roe deer density decreased, males killed sheep at higher rates, and this pattern held for both high and low sheep densities. Similarly, females killed sheep at higher rates in areas with high densities of sheep and low densities of roe deer. However, when sheep densities were low females rarely killed sheep irrespective of roe deer density. Our quantification of depredation rates can be the first step towards establishing fairer compensation systems based on more accurate and area specific estimation of losses. This study demonstrates how we can use ecological theory to predict where losses of sheep will be greatest, and can be used to identify areas where mitigation measures are most likely to be needed.
Density of Wild Prey Modulates Lynx Kill Rates on Free-Ranging Domestic Sheep
Odden, John; Nilsen, Erlend B.; Linnell, John D. C.
2013-01-01
Understanding the factors shaping the dynamics of carnivore–livestock conflicts is vital to facilitate large carnivore conservation in multi-use landscapes. We investigated how the density of their main wild prey, roe deer Capreolus capreolus, modulates individual Eurasian lynx Lynx lynx kill rates on free-ranging domestic sheep Ovis aries across a range of sheep and roe deer densities. Lynx kill rates on free-ranging domestic sheep were collected in south-eastern Norway from 1995 to 2011 along a gradient of different livestock and wild prey densities using VHF and GPS telemetry. We used zero-inflated negative binomial (ZINB) models including lynx sex, sheep density and an index of roe deer density as explanatory variables to model observed kill rates on sheep, and ranked the models based on their AICc values. The model including the effects of lynx sex and sheep density in the zero-inflation model and the effect of lynx sex and roe deer density in the negative binomial part received most support. Irrespective of sheep density and sex, we found the lowest sheep kill rates in areas with high densities of roe deer. As roe deer density decreased, males killed sheep at higher rates, and this pattern held for both high and low sheep densities. Similarly, females killed sheep at higher rates in areas with high densities of sheep and low densities of roe deer. However, when sheep densities were low females rarely killed sheep irrespective of roe deer density. Our quantification of depredation rates can be the first step towards establishing fairer compensation systems based on more accurate and area specific estimation of losses. This study demonstrates how we can use ecological theory to predict where losses of sheep will be greatest, and can be used to identify areas where mitigation measures are most likely to be needed. PMID:24278123
Miyazaki, Hiroyasu; Yoshida, Mutsumi; Samura, Keiji; Matsumoto, Hiroyoshi; Ikemoto, Fumihiko; Tagawa, Masahiro
2002-01-01
Ranges in diurnal variation and the patterns of body temperature (T), blood pressure (BP), heart rate (HR) and locomotor activity (LA) in 61 laboratory beagle dogs were analyzed using a telemetry system. Body temperature, BP, HR and LA increased remarkably at feeding time. Locomotor activity increased sporadically during the other periods. Body temperature was maintained at the higher value after feeding but had decreased by 0.2 C by early the next morning. Blood pressure fell to a lower value after feeding but had increased by 2.8% by early the next morning. Heart rate decreased progressively after feeding and was 14.5% lower the next morning. This study determined that in laboratory beagles the ranges of diurnal variation and patterns of T, BP and HR are significantly different from those reported in humans and rodents, and that over 24 hr these physiological changes were associated with their sporadic wake-sleep cycles of the dogs.
Potential incremental seepage losses in an alluvial channel in the Rio Grande Basin, New Mexico
Gold, R.L.
1985-01-01
A two-dimensional, digital, cross-sectional model was used to simulate seepage of water from an alluvial channel, which had the general characteristic of the Rio Grande channel, into the underlying alluvium within the reach from Cochiti Dam to Elephant Butte Reservoir. Seepage rates were determined for losing and gaining reaches, and reaches affected by pumping of ground water. The seepage rates were computed for stream surcharges (height of additional water applied on top of base flow) ranging from 0.5 foot to 3 feet and for application periods ranging from 1 to 100 days. The net seepage rates, which were nearly identical for each type of reach, ranged from 0.0 cubic foot per second per mile of channel length for a 0.5 foot surcharge applied for 1 day to 0.37 cubic foot per second per mile of channel length for a 3 feet surcharge applied for 100 days, followed by a 180 day seepage return flow from the aquifer. (USGS)
Thermal wind from hot accretion flows at large radii
NASA Astrophysics Data System (ADS)
Bu, De-Fu; Yang, Xiao-Hong
2018-06-01
We study slowly rotating accretion flow at parsec and subparsec scales irradiated by low-luminosity active galactic nuclei. We take into account the Compton heating, photoionization heating by the central X-rays. The bremsstrahlung cooling, recombination, and line cooling are also included. We find that due to the Compton heating, wind can be thermally driven. The power of wind is in the range (10-6-10-3) LEdd, with LEdd being the Eddington luminosity. The mass flux of wind is in the range (0.01-1) \\dot{M}_Edd (\\dot{M}_Edd= L_Edd/0.1c^2 is the Eddington accretion rate, c is speed of light). We define the wind generation efficiency as ɛ = P_W/\\dot{M}_BHc^2, with PW being wind power, \\dot{M}_BH being the mass accretion rate on to the black hole. ɛ lies in the range 10-4-1.18. Wind production efficiency decreases with increasing mass accretion rate. The possible role of the thermally driven wind in the active galactic feedback is briefly discussed.
Multi-point optimization of recirculation flow type casing treatment in centrifugal compressors
NASA Astrophysics Data System (ADS)
Tun, Min Thaw; Sakaguchi, Daisaku
2016-06-01
High-pressure ratio and wide operating range are highly required for a turbocharger in diesel engines. A recirculation flow type casing treatment is effective for flow range enhancement of centrifugal compressors. Two ring grooves on a suction pipe and a shroud casing wall are connected by means of an annular passage and stable recirculation flow is formed at small flow rates from the downstream groove toward the upstream groove through the annular bypass. The shape of baseline recirculation flow type casing is modified and optimized by using a multi-point optimization code with a metamodel assisted evolutionary algorithm embedding a commercial CFD code CFX from ANSYS. The numerical optimization results give the optimized design of casing with improving adiabatic efficiency in wide operating flow rate range. Sensitivity analysis of design parameters as a function of efficiency has been performed. It is found that the optimized casing design provides optimized recirculation flow rate, in which an increment of entropy rise is minimized at grooves and passages of the rotating impeller.
Fast, High-Resolution Terahertz Radar Imaging at 25 Meters
NASA Technical Reports Server (NTRS)
Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria; Talukder, Ashit; Panangadan, Anand V.; Peay, Chris S.; Siegel, Peter H.
2010-01-01
We report improvements in the scanning speed and standoff range of an ultra-wide bandwidth terahertz (THz) imaging radar for person-borne concealed object detection. Fast beam scanning of the single-transceiver radar is accomplished by rapidly deflecting a flat, light-weight subreflector in a confocal Gregorian optical geometry. With RF back-end improvements also implemented, the radar imaging rate has increased by a factor of about 30 compared to that achieved previously in a 4 m standoff prototype instrument. In addition, a new 100 cm diameter ellipsoidal aluminum reflector yields beam spot diameters of approximately 1 cm over a 50x50 cm field of view at a range of 25 m, although some aberrations are observed that probably arise from misaligned optics. Through-clothes images of a concealed threat at 25 m range, acquired in 5 seconds, are presented, and the impact of reduced signal-to-noise from an even faster frame rate is analyzed. These results inform the system requirements for eventually achieving sub-second or video-rate THz radar imaging.
Guelpa, Valérian; Laurent, Guillaume J; Sandoz, Patrick; Zea, July Galeano; Clévy, Cédric
2014-03-12
This paper presents a visual measurement method able to sense 1D rigid body displacements with very high resolutions, large ranges and high processing rates. Sub-pixelic resolution is obtained thanks to a structured pattern placed on the target. The pattern is made of twin periodic grids with slightly different periods. The periodic frames are suited for Fourier-like phase calculations-leading to high resolution-while the period difference allows the removal of phase ambiguity and thus a high range-to-resolution ratio. The paper presents the measurement principle as well as the processing algorithms (source files are provided as supplementary materials). The theoretical and experimental performances are also discussed. The processing time is around 3 µs for a line of 780 pixels, which means that the measurement rate is mostly limited by the image acquisition frame rate. A 3-σ repeatability of 5 nm is experimentally demonstrated which has to be compared with the 168 µm measurement range.
Guelpa, Valérian; Laurent, Guillaume J.; Sandoz, Patrick; Zea, July Galeano; Clévy, Cédric
2014-01-01
This paper presents a visual measurement method able to sense 1D rigid body displacements with very high resolutions, large ranges and high processing rates. Sub-pixelic resolution is obtained thanks to a structured pattern placed on the target. The pattern is made of twin periodic grids with slightly different periods. The periodic frames are suited for Fourier-like phase calculations—leading to high resolution—while the period difference allows the removal of phase ambiguity and thus a high range-to-resolution ratio. The paper presents the measurement principle as well as the processing algorithms (source files are provided as supplementary materials). The theoretical and experimental performances are also discussed. The processing time is around 3 μs for a line of 780 pixels, which means that the measurement rate is mostly limited by the image acquisition frame rate. A 3-σ repeatability of 5 nm is experimentally demonstrated which has to be compared with the 168 μm measurement range. PMID:24625736
A low timing jitter picosecond microchip laser pumped by pulsed LD
NASA Astrophysics Data System (ADS)
Wang, Sha; Wang, Yan-biao; Feng, Guoying; Zhou, Shou-huan
2016-07-01
SESAM passively Q-switched microchip laser is a very promising instrument to replace mode locked lasers to obtain picosecond pulses. The biggest drawback of a passively Q-switched microchip laser is its un-avoided large timing jitter, especially when the pump intensity is low, i.e. at low laser repetition rate range. In order to obtain a low timing jitter passively Q-switched picosecond microchip laser in the whole laser repetition rate range, a 1000 kHz pulsed narrow bandwidth Fiber Bragg Grating (FBG) stablized laser diode was used as the pump source. By tuning the pump intensity, we could control the output laser frequency. In this way, we achieved a very low timing jitter passively Q-switched picosecond laser at 2.13 mW, 111.1 kHz. The relative timing jitter was only 0.0315%, which was around 100 times smaller compared with a cw LD pumped microchip working at hundred kilohertz repetition rate frequency range.
Wei, Fang; Lu, Bin; Wang, Jian; Xu, Dan; Pan, Zhengqing; Chen, Dijun; Cai, Haiwen; Qu, Ronghui
2015-02-23
A precision and broadband laser frequency swept technique is experimentally demonstrated. Using synchronous current compensation, a slave diode laser is dynamically injection-locked to a specific high-order modulation-sideband of a narrow-linewidth master laser modulated by an electro-optic modulator (EOM), whose driven radio frequency (RF) signal can be agilely, precisely controlled by a frequency synthesizer, and the high-order modulation-sideband enables multiplied sweep range and tuning rate. By using 5th order sideband injection-locking, the original tuning range of 3 GHz and tuning rate of 0.5 THz/s is multiplied by 5 times to 15 GHz and 2.5 THz/s respectively. The slave laser has a 3 dB-linewidth of 2.5 kHz which is the same to the master laser. The settling time response of a 10 MHz frequency switching is 2.5 µs. By using higher-order modulation-sideband and optimized experiment parameters, an extended sweep range and rate could be expected.
Basis convergence of range-separated density-functional theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Franck, Odile, E-mail: odile.franck@etu.upmc.fr; Mussard, Bastien, E-mail: bastien.mussard@upmc.fr; CNRS, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris
2015-02-21
Range-separated density-functional theory (DFT) is an alternative approach to Kohn-Sham density-functional theory. The strategy of range-separated density-functional theory consists in separating the Coulomb electron-electron interaction into long-range and short-range components and treating the long-range part by an explicit many-body wave-function method and the short-range part by a density-functional approximation. Among the advantages of using many-body methods for the long-range part of the electron-electron interaction is that they are much less sensitive to the one-electron atomic basis compared to the case of the standard Coulomb interaction. Here, we provide a detailed study of the basis convergence of range-separated density-functional theory. Wemore » study the convergence of the partial-wave expansion of the long-range wave function near the electron-electron coalescence. We show that the rate of convergence is exponential with respect to the maximal angular momentum L for the long-range wave function, whereas it is polynomial for the case of the Coulomb interaction. We also study the convergence of the long-range second-order Møller-Plesset correlation energy of four systems (He, Ne, N{sub 2}, and H{sub 2}O) with cardinal number X of the Dunning basis sets cc − p(C)V XZ and find that the error in the correlation energy is best fitted by an exponential in X. This leads us to propose a three-point complete-basis-set extrapolation scheme for range-separated density-functional theory based on an exponential formula.« less
Waninge, Aly; van der Putten, Annette A J; Stewart, Roy E; Steenbergen, Bert; van Wijck, Ruud; van der Schans, Cees P
2013-11-01
Because physical fitness and health are related to physical activity, it is important to gain an insight into the physical activity levels of persons with profound intellectual and multiple disabilities (PIMD). The purpose of this study was to examine heart rate patterns to measure the activity levels of persons with PIMD and to analyze these heart rate patterns according to participant characteristics, observed level of activity, days, and time of day. The heart rate patterns of 24 participants with PIMD were measured continuously using a heart rate monitor for 8 h · d for a period of 6 days. Physical activity levels were measured with questionnaires. Data were analyzed using multilevel analysis. The results indicate that the participants use only 32% of their heart rate reserve over 6 days. The intensity of heart rate reserve ranged from 1 to 62%. On a given day, wide ranges in heart rates between participants and within persons were observed. Between days, only small ranges in the heart rate were found. The participants could be grouped into 4 classes according to their heart rate. In addition, factors such as time of day, physical activity, and age are significantly related to heart rate patterns. In conclusion, this study is an important first step in exploring activity patterns based on heart rate patterns in persons with PIMD. The participants used relatively small fractions of their heart rate reserves. Time of day and age appear to have a considerable influence on heart rate patterns. The observed classes in heart rate patterns suggest that other probably more personal and psychosocial factors have significant influences on heart rate patterns, as well.
Finite metapopulation models with density-dependent migration and stochastic local dynamics
Saether, B.-E.; Engen, S.; Lande, R.
1999-01-01
The effects of small density-dependent migration on the dynamics of a metapopulation are studied in a model with stochastic local dynamics. We use a diffusion approximation to study how changes in the migration rate and habitat occupancy affect the rates of local colonization and extinction. If the emigration rate increases or if the immigration rate decreases with local population size, a positive expected rate of change in habitat occupancy is found for a greater range of habitat occupancies than when the migration is density-independent. In contrast, the reverse patterns of density dependence in respective emigration and immigration reduce the range of habitat occupancies where the metapopulation will be viable. This occurs because density-dependent migration strongly influences both the establishment and rescue effects in the local dynamics of metapopulations.
Evaporation rate and vapor pressure of selected polymeric lubricating oils.
NASA Technical Reports Server (NTRS)
Gardos, M. N.
1973-01-01
A recently developed ultrahigh-vacuum quartz spring mass sorption microbalance has been utilized to measure the evaporation rates of several low-volatility polymeric lubricating oils at various temperatures. The evaporation rates are used to calculate the vapor pressures by the Langmuir equation. A method is presented to accurately estimate extended temperature range evaporation rate and vapor pressure data for polymeric oils, incorporating appropriate corrections for the increases in molecular weight and the change in volatility of the progressively evaporating polymer fractions. The logarithms of the calculated data appear to follow linear relationships within the test temperature ranges, when plotted versus 1000/T. These functions and the observed effusion characteristics of the fluids on progressive volatilization are useful in estimating evaporation rate and vapor pressure changes on evaporative depletion.
How long is the memory of the US stock market?
NASA Astrophysics Data System (ADS)
Ferreira, Paulo; Dionísio, Andreia
2016-06-01
The Efficient Market Hypothesis (EMH), one of the most important hypothesis in financial economics, argues that return rates have no memory (correlation) which implies that agents cannot make abnormal profits in financial markets, due to the possibility of arbitrage operations. With return rates for the US stock market, we corroborate the fact that with a linear approach, return rates do not show evidence of correlation. However, linear approaches might not be complete or global, since return rates could suffer from nonlinearities. Using detrended cross-correlation analysis and its correlation coefficient, a methodology which analyzes long-range behavior between series, we show that the long-range correlation of return rates only ends in the 149th lag, which corresponds to about seven months. Does this result undermine the EMH?
Influence of temperature on growth rate and lag phase of fungi isolated from Argentine corn.
González, H H; Resnik, S L; Vaamonde, G
1988-03-01
The influence of temperature on the growth of nine strains of fungi belonging to the genera Eurotium, Aspergillus, Penicillium and Fusarium has been investigated for the temperature range 15-35 degrees C. The lag phase and the growth rate were evaluated by using a laboratory medium. The maximum growth rate for E. repens, A. wentii and P. chrysogenum was observed at about 25 degrees C, for P. citrinum near 30 degrees C and for F. semitectum and F. moniliforme between 20 and 25 degrees C. The growth rate of A. niger, A. flavus and A. parasiticus increased with increasing temperatures in the range studied. For all strains studied it appeared that the higher the growth rate the lower the lag phase was.
Dynamic tensile fracture of mortar at ultra-high strain-rates
NASA Astrophysics Data System (ADS)
Erzar, B.; Buzaud, E.; Chanal, P.-Y.
2013-12-01
During the lifetime of a structure, concrete and mortar may be exposed to highly dynamic loadings, such as impact or explosion. The dynamic fracture at high loading rates needs to be well understood to allow an accurate modeling of this kind of event. In this work, a pulsed-power generator has been employed to conduct spalling tests on mortar samples at strain-rates ranging from 2 × 104 to 4 × 104 s-1. The ramp loading allowed identifying the strain-rate anytime during the test. A power law has been proposed to fit properly the rate-sensitivity of tensile strength of this cementitious material over a wide range of strain-rate. Moreover, a specimen has been recovered damaged but unbroken. Micro-computed tomography has been employed to study the characteristics of the damage pattern provoked by the dynamic tensile loading.
Vowles, Kevin E; McEntee, Mindy L; Julnes, Peter Siyahhan; Frohe, Tessa; Ney, John P; van der Goes, David N
2015-04-01
Opioid use in chronic pain treatment is complex, as patients may derive both benefit and harm. Identification of individuals currently using opioids in a problematic way is important given the substantial recent increases in prescription rates and consequent increases in morbidity and mortality. The present review provides updated and expanded information regarding rates of problematic opioid use in chronic pain. Because previous reviews have indicated substantial variability in this literature, several steps were taken to enhance precision and utility. First, problematic use was coded using explicitly defined terms, referring to different patterns of use (ie, misuse, abuse, and addiction). Second, average prevalence rates were calculated and weighted by sample size and study quality. Third, the influence of differences in study methodology was examined. In total, data from 38 studies were included. Rates of problematic use were quite broad, ranging from <1% to 81% across studies. Across most calculations, rates of misuse averaged between 21% and 29% (range, 95% confidence interval [CI]: 13%-38%). Rates of addiction averaged between 8% and 12% (range, 95% CI: 3%-17%). Abuse was reported in only a single study. Only 1 difference emerged when study methods were examined, where rates of addiction were lower in studies that identified prevalence assessment as a primary, rather than secondary, objective. Although significant variability remains in this literature, this review provides guidance regarding possible average rates of opioid misuse and addiction and also highlights areas in need of further clarification.
High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results
NASA Technical Reports Server (NTRS)
Franz, Russell
2008-01-01
An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This report discusses system configuration and the flight test results.
Rain rate range profiling from a spaceborne radar
NASA Technical Reports Server (NTRS)
Meneghini, R.
1980-01-01
At certain frequencies and incidence angles the relative invariance of the surface scattering properites over land can be used to estimate the total attenuation and the integrated rain from a spaceborne attenuation-wavelength radar. The technique is generalized so that rain rate profiles along the radar beam can be estimated, i.e., rain rate determination at each range bin. This is done by modifying the standard algorithm for an attenuating-wavelength radar to include in it the measurement of the total attenuation. Simple error analyses of the estimates show that this type of profiling is possible if the total attenuation can be measured with a modest degree of accuracy.
High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results
NASA Technical Reports Server (NTRS)
Franz, Russell
2007-01-01
An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This paper discusses system configuration and the flight test results.
Kinetics of Mixed Microbial Assemblages Enhance Removal of Highly Dilute Organic Substrates
Lewis, David L.; Hodson, Robert E.; Hwang, Huey-Min
1988-01-01
Our experiments with selected organic substrates reveal that the rate-limiting process governing microbial degradation rates changes with substrate concentration, S, in such a manner that substrate removal is enhanced at lower values of S. This enhancement is the result of the dominance of very efficient systems for substrate removal at low substrate concentrations. The variability of dominant kinetic parameters over a range of S causes the kinetics of complex assemblages to be profoundly dissimilar to those of systems possessing a single set of kinetic parameters; these findings necessitate taking a new approach to predicting substrate removal rates over wide ranges of S. PMID:16347715
The nonuniformity of antibody distribution in the kidney and its influence on dosimetry.
Flynn, Aiden A; Pedley, R Barbara; Green, Alan J; Dearling, Jason L; El-Emir, Ethaar; Boxer, Geoffrey M; Boden, Robert; Begent, Richard H J
2003-02-01
The therapeutic efficacy of radiolabeled antibody fragments can be limited by nephrotoxicity, particularly when the kidney is the major route of extraction from the circulation. Conventional dose estimates in kidney assume uniform dose deposition, but we have shown increased antibody localization in the cortex after glomerular filtration. The purpose of this study was to measure the radioactivity in cortex relative to medulla for a range of antibodies and to assess the validity of the assumption of uniformity of dose deposition in the whole kidney and in the cortex for these antibodies with a range of radionuclides. Storage phosphor plate technology (radioluminography) was used to acquire images of the distributions of a range of antibodies of various sizes, labeled with 125I, in kidney sections. This allowed the calculation of the antibody concentration in the cortex relative to the medulla. Beta-particle point dose kernels were then used to generate the dose-rate distributions from 14C, 131I, 186Re, 32P and 90Y. The correlation between the actual dose-rate distribution and the corresponding distribution calculated assuming uniform antibody distribution throughout the kidney was used to test the validity of estimating dose by assuming uniformity in the kidney and in the cortex. There was a strong inverse relationship between the ratio of the radioactivity in the cortex relative to that in the medulla and the antibody size. The nonuniformity of dose deposition was greatest with the smallest antibody fragments but became more uniform as the range of the emissions from the radionuclide increased. Furthermore, there was a strong correlation between the actual dose-rate distribution and the distribution when assuming a uniform source in the kidney for intact antibodies along with medium- to long-range radionuclides, but there was no correlation for small antibody fragments with any radioisotope or for short-range radionuclides with any antibody. However, when the cortex was separated from the whole kidney, the correlation between the actual dose-rate distribution and the assumed dose-rate distribution, if the source was uniform, increased significantly. During radioimmunotherapy, the extent of nonuniformity of dose deposition in the kidney depends on the properties of the antibody and radionuclide. For dosimetry estimates, the cortex should be taken as a separate source region when the radiopharmaceutical is small enough to be filtered by the glomerulus.
NASA Astrophysics Data System (ADS)
Mangano, J.; O'Connor, J. E.; Jones, K. L.; Wallick, R.
2011-12-01
Many topographic, hydrologic, and land use variables affect the supply and transport of bed-material in rivers, but the underlying geology is a key factor controlling both the volume of introduced material and the attrition of bed-material as it moves downstream. Recent and ongoing USGS river studies in Western Oregon document strong links between geologic province and bed-material transport. Rivers originating in the Mesozoic metamorphic and intrusive igneous rocks of the Klamath terranes of southwestern Oregon have the greatest gravel transport rates (and channel and valley-bottom morphologies reflecting high bed-material fluxes), whereas the generally lesser amounts of gravel in streams that drain Oregon's Coast Range and western Cascade Range owes in large part to Tertiary sedimentary and volcanic units underlying most of these basins. Aspects of these differences are controlled by supply as well as clast attrition. Here we aim to quantify bed-material attrition rates associated with the five main geologic provinces of Western Oregon: the Klamath terranes, Western Cascades, High Cascades, Coast Range sedimentary rocks, and Coast Range volcanic rocks. Bed-material samples were collected throughout the region from streams that drain a single geologic province and tumbled with a lapidary tumbler to determine relative attrition rates. Two kilograms of each sample were sorted into an initial distribution of clast sizes (from 16 to 64mm) and tumbled, with periodic breaks to reweigh and sieve the sample. Results show marked differences in attrition rates, with the sedimentary rocks of the Coast Range having weight loss coefficients between 1.206 and 0.211/km, orders of magnitude greater than all of the other sampled provinces. For comparison, bed material from the Klamath terranes have weight loss coefficients ranging from 0.013 to 0.005/km, and a control sample of quartzite clasts (from the Klamath terranes) has a weight loss coefficient of 0.001/km. These results confirm that bed-material attrition is an important process affecting bed-material supply and transport, and will allow for more complete development of regional bed-material sediment budgets in ongoing efforts to understand patterns of gravel abundance and channel morphology in rivers of Western Oregon.
Stolworthy, Dean K; Zirbel, Shannon A; Howell, Larry L; Samuels, Marina; Bowden, Anton E
2014-05-01
The soft tissues of the spine exhibit sensitivity to strain-rate and temperature, yet current knowledge of spine biomechanics is derived from cadaveric testing conducted at room temperature at very slow, quasi-static rates. The primary objective of this study was to characterize the change in segmental flexibility of cadaveric lumbar spine segments with respect to multiple loading rates within the range of physiologic motion by using specimens at body or room temperature. The secondary objective was to develop a predictive model of spine flexibility across the voluntary range of loading rates. This in vitro study examines rate- and temperature-dependent viscoelasticity of the human lumbar cadaveric spine. Repeated flexibility tests were performed on 21 lumbar function spinal units (FSUs) in flexion-extension with the use of 11 distinct voluntary loading rates at body or room temperature. Furthermore, six lumbar FSUs were loaded in axial rotation, flexion-extension, and lateral bending at both body and room temperature via a stepwise, quasi-static loading protocol. All FSUs were also loaded using a control loading test with a continuous-speed loading-rate of 1-deg/sec. The viscoelastic torque-rotation response for each spinal segment was recorded. A predictive model was developed to accurately estimate spine segment flexibility at any voluntary loading rate based on measured flexibility at a single loading rate. Stepwise loading exhibited the greatest segmental range of motion (ROM) in all loading directions. As loading rate increased, segmental ROM decreased, whereas segmental stiffness and hysteresis both increased; however, the neutral zone remained constant. Continuous-speed tests showed that segmental stiffness and hysteresis are dependent variables to ROM at voluntary loading rates in flexion-extension. To predict the torque-rotation response at different loading rates, the model requires knowledge of the segmental flexibility at a single rate and specified temperature, and a scaling parameter. A Bland-Altman analysis showed high coefficients of determination for the predictive model. The present work demonstrates significant changes in spine segment flexibility as a result of loading rate and testing temperature. Loading rate effects can be accounted for using the predictive model, which accurately estimated ROM, neutral zone, stiffness, and hysteresis within the range of voluntary motion. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Zhe; Xiao, Yan; Yang, Jixiang; Li, Chao; Gao, Xia; Guo, Jinsong
2017-11-01
Turbulent mixing, in particular on a small scale, affects the growth of microalgae by changing diffusive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the cellular stoichiometry and phosphorus storage of microalgae under different turbulent mixing conditions. Aphanizomenon flos-aquae were cultivated in different stirring batch reactors with turbulent dissipation rates ranging from 0.001 51 m2/s3 to 0.050 58 m2/s3, the latter being the highest range observed in natural aquatic systems. Samples were taken in the exponential growth phase and compared with samples taken when the reactor was completely stagnant. Results indicate that, within a certain range, turbulent mixing stimulates the growth of A. flos-aquae. An inhibitory effect on growth rate was observed at the higher range. Photosynthesis activity, in terms of maximum effective quantum yield of PSII (the ratio of F v/ F m) and cellular chlorophyll a, did not change significantly in response to turbulence. However, Chl a/C mass ratio and C/N molar ratio, showed a unimodal response under a gradient of turbulent mixing, similar to growth rate. Moreover, we found that increases in turbulent mixing might stimulate respiration rates, which might lead to the use of polyphosphate for the synthesis of cellular constituents. More research is required to test and verify the hypothesis that turbulent mixing changes the diffusive sublayer, regulating the nutrient flux of cells.
Savage, Jessica A; Cavender-Bares, Jeannine
2013-08-01
With increasing concern about the ecological consequences of global climate change, there has been renewed interest in understanding the processes that determine species range limits. We tested a long-hypothesized trade-off between freezing tolerance and growth rate that is often used to explain species range limits. We grew 24 willow and poplar species (family Salicaceae) collected from across North America in a greenhouse common garden under two climate treatments. Maximum entropy models were used to describe species distributions and to estimate species-specific climate parameters. A range of traits related to freezing tolerance, including senescence, budburst, and susceptibility to different temperature minima during and after acclimation were measured. As predicted, species from colder climates exhibited higher freezing tolerance and slower growth rates than species from warmer climates under certain environmental conditions. However, the average relative growth rate (millimeters per meter per day) of northern species markedly increased when a subset of species was grown under a long summer day length (20.5 h), indicating that genetically based day-length cues are required for growth regulation in these species. We conclude that the observed relationship between freezing tolerance and growth rate is not driven by differences in species' intrinsic growth capacity but by differences in the environmental cues that trigger growth. We propose that the coordinated evolution of freezing tolerance and growth phenology could be important in circumscribing willow and poplar range limits and may have important implications for species' current and future distributions.
Flexible Ureteroscopic Management of Horseshoe Kidney Renal Calculi.
Ding, Jie; Huang, Yunteng; Gu, Siping; Chen, Yifan; Peng, Jie; Bai, Qiang; Ye, Min; Qi, Jun
2015-01-01
To evaluate the clinical efficacy of flexible ureteroscope (F-URS) combined with holmium laser lithotripter in treating renal calculi in horseshoe kidney. From November 2010 to December 2013, the medical history and charts of sixteen patients (mean age 42.9 ± 11.6 years, range 26-66 years), including 13 males and 3 females were analyzed retrospectively. Mean stone burden was 29 ± 8 mm (range 17-42 mm2). Mean stone digitized surface area (DSA) was 321 ± 94 mm2 (range 180-538 mm2). Under spinal anesthesia in a modified lithotomy position with the head down, rigid ureteroscope was placed firstly into the ureter to reach the level of the pelvis, a zebra guide wire was inserted and following the removal of the rigid ureteroscope, an ureteral access sheath was positioned along the guide wire, then passed the URF P-5 flexible ureteroscope into the renal cavities over the guidewire. After locating the stones, holmium laser lithotripsy was performed. The average operative time was 92 ± 16 minutes (range 74-127 min.). No major complications were encountered. Ten patients obtained stone-free status with one session, four obtained stone-free status after two sessions. Single session stone-free rate was 62.5%, overall stone-free rate was 87.5%. Two patients have small residual stones in the lower pole. F-URS combined with holmium laser lithotripter and nitinol basket, is safe and effective in dealing with moderate stone diameter (<30 mm) in HSKs with high clearance rates and low complication rates.
Newcombe, John R; Cuervo-Arango, Juan
2013-03-12
It is believed that during the spring transition, the developing follicle tends to grow more slowly, persist longer and grow to a larger diameter prior to ovulation than at subsequent oestrus periods. A general suspicion, that the first ovulation of the year is less fertile than subsequent ovulations could be explained by a slower growth rate of the ovulatory follicle during transition with the consequent production of a subfertile oocyte. By detailed serial examination of the same group of Irish Draught mares over three winter/spring periods, no significant difference was found in either growth rate or pre-ovulatory diameter when compared with subsequent ovulations. Mean growth rates over the ten days prior to ovulation were 2.20 mm/day (range 1.18 to 3.64) and 2.19 mm/day (range 1.25 to 3.41) for first and subsequent ovulations respectively. Mean maximum pre-ovulatory diameters were 44.7 mm (range 35 to 59) and 43.5 mm (range 31 to 57.5) for first and subsequent ovulations respectively. The impression gained by practitioners that the first follicle develops more slowly during the transition to the first ovulation of the season may be due to less frequent examinations and consequently a failure to observe and record that follicles may grow and then regress during this period. The largest follicle observed a few days previously is not necessarily the same large follicle found at a later examination.
Vocal impact of a prolonged reading task in dysphonic versus normophonic female teachers.
Remacle, Angélique; Morsomme, Dominique; Berrué, Elise; Finck, Camille
2012-11-01
This study evaluates the effect of a 2-hour reading task between 70 and 75 dB(A) in 16 normophonic and 16 dysphonic female teachers with vocal nodules. Objective measurements (acoustic analysis, voice range measurements, and aerodynamic measurements) and subjective self-ratings were collected before and every 30 minutes during the reading to determine the voice evolution in both groups. Fundamental frequency, lowest frequency, highest frequency (F-High), highest intensity, and intensity range increase through the reading, whereas shimmer decreases. Maximum phonation time decreases after 30 minutes. Estimated subglottal pressure (ESP) and sound pressure level increase during the first hour. Afterward, ESP decreases. Self-ratings worsen through time. When comparing the normophonic and the dysphonic teachers, self-ratings reveal more complaints in the dysphonic group. Few differences in objective measurements are found between both groups: normophonic teachers show lower ESP, higher F-High, and greater frequency range. Frequency modifications from acoustic analysis and voice range measurements suggest an increased laryngeal tension during vocal load, while subjects perceive a worsening of voice. Aerodynamic parameters depict first a deterioration of voice efficiency and then an adaptation to the prolonged reading. The comparison between both groups shows a discrepancy between objective measurements and self-ratings, suggesting that both approaches are necessary to have a complete view of vocal load effects. Surprisingly, both groups behave similarly through vocal load, without more or quicker deterioration of voice in the dysphonic group. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.
Effects of air current speed on gas exchange in plant leaves and plant canopies.
Kitaya, Y; Tsuruyama, J; Shibuya, T; Yoshida, M; Kiyota, M
2003-01-01
To obtain basic data on adequate air circulation to enhance plant growth in a closed plant culture system in a controlled ecological life support system (CELSS), an investigation was made of the effects of the air current speed ranging from 0.01 to 1.0 m s-1 on photosynthesis and transpiration in sweetpotato leaves and photosynthesis in tomato seedlings canopies. The gas exchange rates in leaves and canopies were determined by using a chamber method with an infrared gas analyzer. The net photosynthetic rate and the transpiration rate increased significantly as the air current speeds increased from 0.01 to 0.2 m s-1. The transpiration rate increased gradually at air current speeds ranging from 0.2 to 1.0 m s-1 while the net photosynthetic rate was almost constant at air current speeds ranging from 0.5 to 1.0 m s-1. The increase in the net photosynthetic and transpiration rates were strongly dependent on decreased boundary-layer resistances against gas diffusion. The net photosynthetic rate of the plant canopy was doubled by an increased air current speed from 0.1 to 1.0 m s-1 above the plant canopy. The results demonstrate the importance of air movement around plants for enhancing the gas exchange in the leaf, especially in plant canopies in the CELSS. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
Lincoln estimates of mallard (Anas platyrhynchos) abundance in North America.
Alisauskas, Ray T; Arnold, Todd W; Leafloor, James O; Otis, David L; Sedinger, James S
2014-01-01
Estimates of range-wide abundance, harvest, and harvest rate are fundamental for sound inferences about the role of exploitation in the dynamics of free-ranging wildlife populations, but reliability of existing survey methods for abundance estimation is rarely assessed using alternative approaches. North American mallard populations have been surveyed each spring since 1955 using internationally coordinated aerial surveys, but population size can also be estimated with Lincoln's method using banding and harvest data. We estimated late summer population size of adult and juvenile male and female mallards in western, midcontinent, and eastern North America using Lincoln's method of dividing (i) total estimated harvest, [Formula: see text], by estimated harvest rate, [Formula: see text], calculated as (ii) direct band recovery rate, [Formula: see text], divided by the (iii) band reporting rate, [Formula: see text]. Our goal was to compare estimates based on Lincoln's method with traditional estimates based on aerial surveys. Lincoln estimates of adult males and females alive in the period June-September were 4.0 (range: 2.5-5.9), 1.8 (range: 0.6-3.0), and 1.8 (range: 1.3-2.7) times larger than respective aerial survey estimates for the western, midcontinent, and eastern mallard populations, and the two population estimates were only modestly correlated with each other (western: r = 0.70, 1993-2011; midcontinent: r = 0.54, 1961-2011; eastern: r = 0.50, 1993-2011). Higher Lincoln estimates are predictable given that the geographic scope of inference from Lincoln estimates is the entire population range, whereas sampling frames for aerial surveys are incomplete. Although each estimation method has a number of important potential biases, our review suggests that underestimation of total population size by aerial surveys is the most likely explanation. In addition to providing measures of total abundance, Lincoln's method provides estimates of fecundity and population sex ratio and could be used in integrated population models to provide greater insights about population dynamics and management of North American mallards and most other harvested species.
Improving Neurodevelopmental Surveillance and Follow-up in Infants with Congenital Heart Disease.
Michael, Mark; Scharf, Rebecca; Letzkus, Lisa; Vergales, Jeffrey
2016-01-01
We hypothesize that neurodevelopmental surveillance of targeted patients with congenital heart disease during the admission for their cardiac surgery would improve neurodevelopmental assessment and outpatient follow-up rates. All patients under 12 months of age who were operated on between October 2013 and October 2014 and were considered at risk for neurodevelopmental delay in accordance with the 2012 American Heart Association Scientific Statement were included. A protocol was implemented to increase surveillance of targeted patients during the hospitalization for their cardiac surgery. A historical control cohort was used from a 6-month period that preceded initiation of the program from July 2012 to December 2012. Univariate analysis assessed the effects of patient demographics, anatomy, postoperative course, and distance from clinic on inpatient screening and follow-up to evaluate areas for future improvement. Neurodevelopmental surveillance in the post-protocol period increased from 21% to 82% (P < .001) as did compliance rates for outpatient follow-up from 38% to 52% (P < .001). Patients receiving consultation were younger (median 1.2 months range 0.3-3.1 vs. 4.0 range 1.2-5.5, P = .002), had a longer intensive care unit duration (median 8 days range 4-13 vs. 4 range 3-8, P = .044), and a longer total hospital duration (median 14 days range 8-25 vs. 8 range 6-16, P = .023). The presence of single ventricle anatomy was associated with a lower follow-up rate at 29% than those with biventricular hearts at 64% (P = .009). Distance from the clinic did not have an effect on follow-up (P = .39). The protocol described increased neurodevelopmental surveillance of high risk patients. Individuals that were younger and in the hospital longer were more likely to be successfully seen and comply with outpatient follow-up than those not receiving inpatient risk assessment. Patients with single ventricle anatomy may benefit from a modified follow-up schedule to improve compliance rates. Travel distance has no effect on likelihood of outpatient cardiac neurodevelopmental follow-up. © 2016 Wiley Periodicals, Inc.
The quality assurance program of organ donation in Tuscany.
Bozzi, G; Saviozzi, A; De Simone, P; Filipponi, F
2008-01-01
Constant monitoring is paramount in order to detect the criticalities and improve the results of the deceased donation process. Concomitant with the institution of a regional transplantation service authority--Organizzazione Toscana Trapianti--in 2003, Tuscany adopted a program of quality assurance of the deceased donation process by compulsory reporting of all encephalic deaths from local intensive care units to the regional transplant office in Florence. The indicators we adopted were the efficiency of deceased donor (DD) identification, expressed as the ratio of encephalic deaths (ED) to total deaths with encephalic lesions (EL) (ie, ED/EL); the efficiency of DD reporting, expressed as the ratio of reported potential DD (RPDD) to total ED (ie, RPDD/ED); the efficacy of the DD process, as the ratio between actual DD (ADD) to total ED (ie, ADD/ED); the conversion rate; the percent of opposition to donation; and the incidence of DD maintenance failures. Data were collected prospectively, stratified by regional hospital consortia (Aziende Sanitarie Locali) and compared with international benchmarks. In the period 2003-2006 the mean efficiency of DD identification was 48.3%+/-4.4% (range 42.6%-53.2%); the mean efficiency of DD reporting was 95.2%+/-2.5% (range 92.5%-98.5%); the mean efficacy of the deceased donation process was 51.8%+/-2.4% (range 48.6%-54.4%); the mean conversion rate was 59.6%+/-2.2% (range 57.6%-62.7%); the mean opposition rate was 31.9%+/-1.1% (range 30.6%-33.2%); and the incidence of DD maintenance failure was 5%+/-2.9% (range 2.2%-8.7%). The breakdown analysis revealed wide interhospital variability in terms of efficiency of DD identification (from a low of 25% to a high of 80%); efficacy of the donation process (from a low of 22% to a high of 79%); and conversion rate (from a low of 29% to a high of 79%). Our results highlight that the donation process gets started in about 50% of eligible cases. Further strategies are favored to address this critical area.
Theoretical Perspectives on the Statics and Dynamics of Species’ Borders in Patchy Environments
Holt, Robert D.; Barfield, Michael
2016-01-01
Understanding range limits is a fundamental problem in ecology and evolutionary biology. In 1963, Mayr argued that “contaminating” gene flow from central populations constrained adaptation in marginal populations, preventing range expansion, while in 1984, Bradshaw suggested that absence of genetic variation prevented species from occurring everywhere. Understanding stability of range boundaries requires unraveling the interplay of demography, gene flow, and evolution of populations in concrete landscape settings. We walk through a set of interrelated spatial scenarios that illustrate interesting complexities of this interplay. To motivate our individual-based model results, we consider a hypothetical zooplankter in a landscape of discrete water bodies coupled by dispersal. We examine how patterns of dispersal influence adaptation in sink habitats where conditions are outside the species’ niche. The likelihood of observing niche evolution (and thus range expansion) over any given timescale depends on (1) the degree of initial maladaptation; (2) pattern (pulsed vs. continuous, uni- vs. bidirectional), timing (juvenile vs. adult), and rate of dispersal (and hence population size); (3) mutation rate; (4) sexuality; and (5) the degree of heterogeneity in the occupied range. We also show how the genetic architecture of polygenic adaptation is influenced by the interplay of selection and dispersal in heterogeneous landscapes. PMID:21956092
Ranging error analysis of single photon satellite laser altimetry under different terrain conditions
NASA Astrophysics Data System (ADS)
Huang, Jiapeng; Li, Guoyuan; Gao, Xiaoming; Wang, Jianmin; Fan, Wenfeng; Zhou, Shihong
2018-02-01
Single photon satellite laser altimeter is based on Geiger model, which has the characteristics of small spot, high repetition rate etc. In this paper, for the slope terrain, the distance of error's formula and numerical calculation are carried out. Monte Carlo method is used to simulate the experiment of different terrain measurements. The experimental results show that ranging accuracy is not affected by the spot size under the condition of the flat terrain, But the inclined terrain can influence the ranging error dramatically, when the satellite pointing angle is 0.001° and the terrain slope is about 12°, the ranging error can reach to 0.5m. While the accuracy can't meet the requirement when the slope is more than 70°. Monte Carlo simulation results show that single photon laser altimeter satellite with high repetition rate can improve the ranging accuracy under the condition of complex terrain. In order to ensure repeated observation of the same point for 25 times, according to the parameters of ICESat-2, we deduce the quantitative relation between the footprint size, footprint, and the frequency repetition. The related conclusions can provide reference for the design and demonstration of the domestic single photon laser altimetry satellite.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Titov, Gene; Lustbader, Jason Aaron
The National Renewable Energy Laboratory's (NREL's) CoolSim MATLAB/Simulink modeling framework was used to explore control strategies for an electric vehicle combined loop system. Three system variants of increased complexity and efficiency were explored: a glycol-based positive temperature coefficient heater (PTC), PTC with power electronics and electric motor (PEEM) waste heat recovery, and PTC with PEEM waste heat recovery plus heat pump versions. Additionally, the benefit of electric motor preheating was considered. A two-level control strategy was developed where the mode selection and component control were treated separately. Only the parameters typically available by vehicle sensors were used to control themore » system. The control approach included a mode selection algorithm and controllers for the compressor speed, cabin blower flow rate, coolant flow rate, and the front-end heat exchanger coolant bypass rate. The electric motor was bypassed by the cooling circuit until its temperature exceeded the coolant inlet temperature. The impact of these thermal systems on electric vehicle range during warmup was simulated for the Urban Dynamometer Driving Schedule (UDDS) and Highway Fuel Economy Test (HWFET2X) drive cycles weighted 45%/55% respectively. A range of ambient temperatures from -20 degrees C to +20 degrees C was considered. NREL's Future Automotive Systems Technology Simulator (FASTSim) vehicle modeling tool showed up to a 10.9% improvement in range for the full system over the baseline during warmup from cold soak. The full system with preheat showed up to 17% improvement in range.« less
Robotic liver surgery: results for 70 resections.
Giulianotti, Pier Cristoforo; Coratti, Andrea; Sbrana, Fabio; Addeo, Pietro; Bianco, Francesco Maria; Buchs, Nicolas Christian; Annechiarico, Mario; Benedetti, Enrico
2011-01-01
Robotic surgery is gaining popularity for digestive surgery; however, its use for liver surgery is reported scarcely. This article reviews a surgeon's experience with the use of robotic surgery for liver resections. From March 2002 to March 2009, 70 robotic liver resections were performed at 2 different centers by a single surgeon. The surgical procedure and postoperative outcome data were reviewed retrospectively. Malignant tumors were indications for resections in 42 (60%) patients, whereas benign tumors were indications in 28 (40%) patients. The median age was 60 years (range, 21-84) and 57% of patients were female. Major liver resections (≥ 3 liver segments) were performed in 27 (38.5%) patients. There were 4 conversions to open surgery (5.7%). The median operative time for a major resection was 313 min (range, 220-480) and 198 min (range, 90-459) for minor resection. The median blood loss was 150 mL (range, 20-1,800) for minor resection and 300 mL (range, 100-2,000) for major resection. The mortality rate was 0%, and the overall rate of complications was 21%. Major morbidity occurred in 4 patients in the major hepatectomies group (14.8%) and in 4 patients in the minor hepatectomies group (9.3%). All complications were managed conservatively and none required reoperation. This preliminary experience shows that robotic surgery can be used safely for liver resections with a limited conversion rate, blood loss, and postoperative morbidity. Robotics offers a new technical option for minimally invasive liver surgery. Copyright © 2011 Mosby, Inc. All rights reserved.
Silvestro, Daniele; Tejedor, Marcelo F; Serrano-Serrano, Martha L; Loiseau, Oriane; Rossier, Victor; Rolland, Jonathan; Zizka, Alexander; Höhna, Sebastian; Antonelli, Alexandre; Salamin, Nicolas
2018-06-20
New World monkeys (platyrrhines) are one of the most diverse groups of primates, occupying today a wide range of ecosystems in the American tropics and exhibiting large variations in ecology, morphology, and behavior. Although the relationships among the almost 200 living species are relatively well understood, we lack robust estimates of the timing of origin, ancestral morphology, and geographic range evolution of the clade. Here we integrate paleontological and molecular evidence to assess the evolutionary dynamics of extinct and extant platyrrhines. We develop novel analytical frameworks to infer the evolution of body mass, changes in latitudinal ranges through time, and species diversification rates using a phylogenetic tree of living and fossil taxa. Our results show that platyrrhines originated 5-10 million years earlier than previously assumed, dating back to the Middle Eocene. The estimated ancestral platyrrhine was small - weighing 0.4 kg - and matched the size of their presumed African ancestors. As the three platyrrhine families diverged, we recover a rapid change in body mass range. During the Miocene Climatic Optimum, fossil diversity peaked and platyrrhines reached their widest latitudinal range, expanding as far South as Patagonia, favored by warm and humid climate and the lower elevation of the Andes. Finally, global cooling and aridification after the middle Miocene triggered a geographic contraction of New World monkeys and increased their extinction rates. These results unveil the full evolutionary trajectory of an iconic and ecologically important radiation of monkeys and showcase the necessity of integrating fossil and molecular data for reliably estimating evolutionary rates and trends.
Lin, Xianghong; Johnson, William L.
1998-01-01
At least quinary alloys form metallic glass upon cooling below the glass transition temperature at a rate less than 10.sup.3 K/s. Such alloys comprise zirconium and/or hafnium in the range of 45 to 65 atomic percent, titanium and/or niobium in the range of 4 to 7.5 atomic percent, and aluminum and/or zinc in the range of 5 to 15 atomic percent. The balance of the alloy compositions comprise copper, iron, and cobalt and/or nickel. The composition is constrained such that the atomic percentage of iron is less than 10 percent. Further, the ratio of copper to nickel and/or cobalt is in the range of from 1:2 to 2:1. The alloy composition formula is: (Zr,Hf).sub.a (Al,Zn).sub.b (Ti,Nb).sub.c (Cu.sub.x Fe.sub.y (Ni,Co).sub.z).sub.d wherein the constraints upon the formula are: a ranges from 45 to 65 atomic percent, b ranges from 5 to 15 atomic percent, c ranges from 4 to 7.5 atomic percent, d comprises the balance, d.multidot.y is less than 10 atomic percent, and x/z ranges from 0.5 to 2.
Hufbauer, Ruth A; Facon, Benoît; Ravigné, Virginie; Turgeon, Julie; Foucaud, Julien; Lee, Carol E; Rey, Olivier; Estoup, Arnaud
2012-01-01
Adaptive evolution is currently accepted as playing a significant role in biological invasions. Adaptations relevant to invasions are typically thought to occur either recently within the introduced range, as an evolutionary response to novel selection regimes, or within the native range, because of long-term adaptation to the local environment. We propose that recent adaptation within the native range, in particular adaptations to human-altered habitat, could also contribute to the evolution of invasive populations. Populations adapted to human-altered habitats in the native range are likely to increase in abundance within areas frequented by humans and associated with human transport mechanisms, thus enhancing the likelihood of transport to a novel range. Given that habitats are altered by humans in similar ways worldwide, as evidenced by global environmental homogenization, propagules from populations adapted to human-altered habitats in the native range should perform well within similarly human-altered habitats in the novel range. We label this scenario ‘Anthropogenically Induced Adaptation to Invade’. We illustrate how it differs from other evolutionary processes that may occur during invasions, and how it can help explain accelerating rates of invasions. PMID:25568032
Lin, X.; Johnson, W.L.
1998-04-07
At least quinary alloys form metallic glass upon cooling below the glass transition temperature at a rate less than 10{sup 3}K/s. Such alloys comprise zirconium and/or hafnium in the range of 45 to 65 atomic percent, titanium and/or niobium in the range of 4 to 7.5 atomic percent, and aluminum and/or zinc in the range of 5 to 15 atomic percent. The balance of the alloy compositions comprise copper, iron, and cobalt and/or nickel. The composition is constrained such that the atomic percentage of iron is less than 10 percent. Further, the ratio of copper to nickel and/or cobalt is in the range of from 1:2 to 2:1. The alloy composition formula is: (Zr,Hf){sub a}(Al,Zn){sub b}(Ti,Nb){sub c}(Cu{sub x}Fe{sub y}(Ni,Co){sub z}){sub d} wherein the constraints upon the formula are: a ranges from 45 to 65 atomic percent, b ranges from 5 to 15 atomic percent, c ranges from 4 to 7.5 atomic percent, d comprises the balance, d{hor_ellipsis}y is less than 10 atomic percent, and x/z ranges from 0.5 to 2.
Tul, Natasa; Lucovnik, Miha; Verdenik, Ivan; Druskovic, Mirjam; Novak, Ziva; Blickstein, Isaac
2013-12-01
To assess the contribution of ART twins to the very preterm birth rate in Slovenia. In this retrospective population-based study we stratified by plurality and gestational age (<32 weeks vs >32 week) all deliveries >24 weeks in women who conceived by ART. We counted the frequencies of all ART liveborn twins among all liveborn infants and among all liveborn twins and frequencies in the subgroup of very preterm births. During the period 1987-2010, there were 13,293 twins (2.73%, range 1.93-3.62%, a nearly 2-fold increase from 1987 to 2010), 6939 infants born after ART (1.42%, range 0.03-2.62%, an 87-fold increase from 1987 to 2010), including 2317 (33.4%, range 14.28-44.83%, a 3-fold increase from 1987 to 2010) twins (0.47% of all deliveries). A total of 425 twin infants (0.99%, range: 1.07-1.2%, insignificant increase) were born at <32 weeks' gestation, including 261 after ART (61.4%, range 20-100%, 5-fold increase). Twins after ART born at <32 weeks comprised 0.05% of all births (range 0.004-0.11%) and increased 27-fold from 1987 to 2010. The incidence of twins after ART born at <32 weeks increased 27-fold from 1987 to 2010 and has not reduced from its peak incidence over the last decade. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Test of the ecological-constraints model on ursine colobus monkeys (Colobus vellerosus) in Ghana.
Teichroeb, Julie A; Sicotte, Pascale
2009-01-01
For group-living mammals, the ecological-constraints model predicts that within-group feeding competition will increase as group size increases, necessitating more daily travel to find food and thereby constraining group size. It provides a useful tool for detecting scramble competition any time it is difficult to determine whether or not food is limiting. We tested the ecological-constraints model on highly folivorous ursine colobus monkeys (Colobus vellerosus) at the Boabeng-Fiema Monkey Sanctuary in Ghana. Three differently sized groups were followed for 13 months and two others were followed for 6 months each in 2004-2005 using focal-animal sampling and ranging scans; ecological plots and phenology surveys were used to determine home-range quality and food availability. There was relatively little difference in home-range quality, monthly food availability, diet, adult female ingestion rates, and rate of travel within food patches between the groups. However, home-range size, day-range length, and percent of time spent feeding all increased with group size. We performed a single large test of the ecological-constraints model by combining several separate Spearman correlations, each testing different predictions under the model, using Fisher's log-likelihood method. It showed that the ecological-constraints model was supported in this study; scramble competition in this population is manifesting in increased ranging and time spent feeding. How costly this increased energy expenditure is for individuals in larger groups remains to be determined. (c) 2008 Wiley-Liss, Inc.
First Test of Long-Range Collisional Drag via Plasma Wave Damping
NASA Astrophysics Data System (ADS)
Affolter, Matthew
2017-10-01
In magnetized plasmas, the rate of particle collisions is enhanced over classical predictions when the cyclotron radius rc is less than the Debye length λD. Classical theories describe local velocity scattering collisions with impact parameters ρ
Rahal, R; Chadder, J; DeCaria, K; Lockwood, G; Bryant, H
2017-04-01
Meaningful performance measures are an important part of the toolkit for health system improvement. The Canadian Partnership Against Cancer has been reporting on pan-Canadian cancer system performance indicators since 2009-work that has led to the availability of standardized measures that can help to shed light on the extent of variation and opportunities for quality improvement across the country. Those measures include a core set of system indicators ranging from prevention and screening, through diagnosis and treatment, to survivorship and end-of-life care. Key indicators were calculated and graphed, showing the range from worst to best result for the provinces and territories included in the data. There were often significant differences in cancer system performance between provinces and territories. For example, smoking prevalence rates ranged from 14% to 62%. The 90th percentile wait times from an abnormal breast screen to resolution (without biopsy) ranged from 4 weeks to 8 weeks. The percentage of breast cancer resections that used breast-conserving surgery rather than mastectomy ranged from 38% to 75%. Clinical trial participation rates for adults ranged from 0.2% to 6.6%. Variations in performance indicators between Canadian jurisdictions suggest potential differences in the planning and delivery of cancer control services and in clinical practice patterns and patient outcomes. Understanding sources of variation can help to identify opportunities for improvements in the quality and outcomes of cancer control service delivery in each province and territory.
Ilhan, Harun; Goritschan, Anna; Paprottka, Phillip; Jakobs, Tobias F; Fendler, Wolfgang P; Bartenstein, Peter; Hacker, Marcus; Haug, Alexander R
2015-03-01
The aim of this study was to evaluate the (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) uptake of primary and secondary liver tumors in a large patient cohort before (90)Y radioembolization. We included 502 patients during the years 2005-2013 (55% male; mean age, 62 ± 11 y), who were examined with (99m)Tc-MAA SPECT or SPECT/CT before planned radioembolization. The patients had colorectal cancer (CRC; n = 195, 38.8%), neuroendocrine tumors (NET; n = 77, 15.3%), mammary cancer (MAM; n = 68, 13.5%), hepatocellular carcinoma (HCC; n = 59, 11.8%), cholangiocellular carcinoma (CCC; n = 40, 8.0%), or urologic tumors (URO; n = 14, 2.8%). SPECT with coregistered contrast-enhanced CT or MR imaging and SPECT/CT images of these patients were analyzed using dedicated software with regard to the (99m)Tc-MAA uptake of the liver tumors. Regions of interest were drawn around the lesions manually and quantified the uptake of up to 3 lesions per patient and also adjacent healthy liver tissue without evidence of tumor. We quantified maximum and mean counts per pixel and calculated tumor-to-background ratio (TBR). Data are reported as mean ± SD. Lesion uptake was classified as being homogeneously high (grade 1), heterogeneously high (grade 2), equal to that of the liver (grade 3), or low (grade 4). Grade 1 uptake was seen in 230 of 1,008 lesions (with the highest rates in sarcoma [47%], MAM [37%], and NET [32%]), grade 2 in 706 lesions (with the highest rates in CRC [77%], HCC [75%], and CCC [74%]), grade 4 in 57 lesions (with the highest rates in pancreatic cancer [17%], sarcoma [SAR] [13%], and MAM [8%]), and grade 3 in only 15 lesions. In quantitative analysis, the mean TBRmax of all lesions was 4.8 ± 4.1 (range, 0.2-50.1), with the highest values in HCC (6.0 ± 4.7; range, 1.4-21.6), NET (5.4 ± 4.9; range, 0.8-43.0), pancreatic cancer (4.0 ± 2.8; range, 0.9-12.2), and CCC (4.7 ± 2.9; range, 0.9-11.6), and the lowest values in SAR (3.5 ± 1.8; range, 0.8-2.7) and MAM (3.6 ± 2.2; range, 0.9-11.6). The mean TBRmean was 1.9 ± 1.0 (range, 0.1-7.2), with the highest values in NET (2.2 ± 1.2; range, 0.2-7.2), HCC (2.1 ± 1.2; range, 0.3-6.3), and CCC (2.0 ± 1.0; range, 0.2-6.3) and the lowest values in MAM (1.7 ± 0.8; range, 0.2-4.1), CRC (1.8 ± 0.9; range, 0.4-6.6), and SAR (1.7 ± 1.1; range, 0.3-3.9). The (99m)Tc-MAA uptake of different tumor entities shows a wide variation, with generally highest values for NET, HCC, and CCC and lowest values for MAM, CRC, and SAR. However, the variation of uptake within the different tumor entities is high. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.
O'Leary, David; Clark, Dennis A.; Izbicki, John A.
2015-01-01
Water levels in the observation well ranged from about 367 to 370 feet below land surface during the period of the study. Measured saturated hydraulic conductivity of core material ranged from 2.1 to 11.0 feet per day. Average vertical infiltration rates in the pilot-scale infiltration pond ranged from 0.7 to 2.4 feet per day. Both denitrifying and nitrate-reducing bacteria were present in drill cutting material in most probable numbers ranging from below detection limits to 2,400,000 for denitrifying and to 93,000 for nitrate-reducing bacteria.
An approach to instrument qualified visual range
NASA Astrophysics Data System (ADS)
Courtade, Benoît; Bonnet, Jordan; Woodruff, Chris; Larson, Josiah; Giles, Andrew; Sonde, Nikhil; Moore, C. J.; Schimon, David; Harris, David Money; Pond, Duane; Way, Scott
2008-04-01
This paper describes a system that calculates aircraft visual range with instrumentation alone. A unique message is encoded using modified binary phase shift keying and continuously flashed at high speed by ALSF-II runway approach lights. The message is sampled at 400 frames per second by an aircraft borne high-speed camera. The encoding is designed to avoid visible flicker and minimize frame rate. Instrument qualified visual range is identified as the largest distance at which the aircraft system can acquire and verify the correct, runway-specific signal. Scaled testing indicates that if the system were implemented on one full ALSF-II fixture, instrument qualified range could be established at 5 miles in clear weather conditions.
Synthesis and analysis of precise spaceborne laser ranging systems, volume 1. [link analysis
NASA Technical Reports Server (NTRS)
Paddon, E. A.
1977-01-01
Measurement accuracy goals of 2 cm rms range estimation error and 0.003 cm/sec rms range rate estimation error, with no more than 1 cm (range) static bias error are requirements for laser measurement systems to be used in planned space-based earth physics investigations. Constraints and parameters were defined for links between a high altitude, transmit/receive satellite (HATRS), and one of three targets: a low altitude target satellite, passive (LATS), and active low altitude target, and a ground-based target, as well as with operations with a primary transmit/receive terminal intended to be carried as a shuttle payload, in conjunction with the Spacelab program.
NASA Technical Reports Server (NTRS)
Sun, Xiaoli; Skillman, David R.; Hoffman, Evan D.; Mao, Dandan; McGarry, Jan F.; Neumann, Gregory A.; McIntire, Leva; Zellar, Ronald S.; Davidson, Frederic M.; Fong, Wai H.;
2013-01-01
We report a free space laser communication experiment from the satellite laser ranging (SLR) station at NASA Goddard Space Flight Center (GSFC) to the Lunar Reconnaissance Orbiter (LRO) in lunar orbit through the on board one-way Laser Ranging (LR) receiver. Pseudo random data and sample image files were transmitted to LRO using a 4096-ary pulse position modulation (PPM) signal format. Reed-Solomon forward error correction codes were used to achieve error free data transmission at a moderate coding overhead rate. The signal fading due to the atmosphere effect was measured and the coding gain could be estimated.
Upgrading and performance of the SAO laser ranging system in Matera
NASA Technical Reports Server (NTRS)
Maddox, J.; Pearlman, M.; Throp, J.; Wohn, J.
1983-01-01
The performance of the SAO lasers was improved considerably in terms of accuracy, range noise, data yield, and reliability. With the narrower laser pulse (2.5-3.0 nsec) and a new analog pulse processing system, the systematic range errors were reduced to 3-5 cm and range noise has been reduced to 5-15 cm on low satellites and 10-18 cm on Lageos. Pulse repetition rate was increased to 30 ppm and considerable improvement has been made in signal-to-noise ratio by using a 3 Angstrom interference filter and by reducing the range gate window down to 200-400 nsec. The first upgraded system was installed in Arequipa, Peru in the spring of 1982. The second upgraded system is now in operation in Matera, Italy. The third system is expected to be installed in Israel during 1984.
Wen, Xuejiao; Qiu, Xiaolan; Han, Bing; Ding, Chibiao; Lei, Bin; Chen, Qi
2018-05-07
Range ambiguity is one of the factors which affect the SAR image quality. Alternately transmitting up and down chirp modulation pulses is one of the methods used to suppress the range ambiguity. However, the defocusing range ambiguous signal can still hold the stronger backscattering intensity than the mainlobe imaging area in some case, which has a severe impact on visual effects and subsequent applications. In this paper, a novel hybrid range ambiguity suppression method for up and down chirp modulation is proposed. The method can obtain the ambiguity area image and reduce the ambiguity signal power appropriately, by applying pulse compression using a contrary modulation rate and CFAR detecting method. The effectiveness and correctness of the approach is demonstrated by processing the archive images acquired by Chinese Gaofen-3 SAR sensor in full-polarization mode.
High altitude flights by ruddy shelduck Tadorna ferruginea during trans-Himalayan migrations
Parr, N.; Bearhop, S.; Douglas, David C.; Takekawa, J.Y.; Prosser, Diann J.; Newman, S.H.; Perry, W.M.; Balachandran, S.; Witt, M.J.; Hou, Y.; Luo, Z.; Hawkes, L.A.
2017-01-01
Birds that migrate across high altitude mountain ranges are faced with the challenge of maintaining vigorous exercise in environments with limited oxygen. Ruddy shelducks are known to use wintering grounds south of the Tibetan Plateau at sea level and breeding grounds north of Himalayan mountain range. Therefore, it is likely these shelducks are preforming high altitude migrations. In this study we analyse satellite telemetry data collected from 15 ruddy shelduck from two populations wintering south of the Tibetan Plateau from 2007 to 2011. During north and south migrations ruddy shelduck travelled 1481 km (range 548–2671 km) and 1238 km (range 548–2689 km) respectively. We find mean maximum altitudes of birds in flight reached 5590 m (range of means 4755–6800 m) and mean maximum climb rates of 0.45 m s–1 (range 0.23–0.74 m s–1). The ruddy shelduck is therefore an extreme high altitude migrant that has likely evolved a range of physiological adaptations in order to complete their migrations.