NASA Astrophysics Data System (ADS)
Morita, Kazuyo; Yamamoto, Kimiko
2017-03-01
Xylan, one of hemicellulose family, block copolymer was newly developed for wide-range directed self-assembly lithography (DSA). Xylan is higher hydrophilic material because of having many hydroxy groups in one molecule. It means that xylan block copolymer has a possibility of high-chi block copolymer. Generally, DSA is focused on microphase separation for smaller size with high-chi block copolymer and not well known for larger size. In this study, xylan block copolymer was confirmed enabling wider range of patterning size, from smaller size to larger size. The key of xylan block copolymer is a new molecular structure of block copolymer and sugar chain control technology. Sugar content is the important parameter for not only micro-phase separation property but also line edge roughness (LER) and defects. Based on the sugar control technology, wide-range (hp 8.3nm to 26nm L/S and CD 10nm to 51nm hole) DSA patterning was demonstrated. Additionally it was confirmed that xylan block copolymer is suitable for sequential infiltration synthesis (SIS) process.
ERIC Educational Resources Information Center
Hutchins, Tiffany L.; Howard, Malinda; Prelock, Patricia A.; Belin, Gayle
2010-01-01
Nationally, the shortage of speech-language pathologists (SLPs) in the schools is growing. As such, it is important to understand factors related to the retention of SLPs in this setting. This study expanded on previous research by examining a wider range of factors that may be related to the retention of SLPs including caseload size, workload…
DOT National Transportation Integrated Search
2016-05-01
Over the past 20 years, drilled shafts have demonstrated increasing popularity over driven : precast piles. Drilled shafts can accommodate a wider range of sizes, and noise and vibration : during construction are significantly reduced. On the other h...
Forest operations for ecosystem management
Robert B. Rummer; John Baumgras; Joe McNeel
1997-01-01
The evolution of modern forest resource management is focusing on ecologically sensitive forest operations. This shift in management strategies is producing a new set of functional requirements for forest operations. Systems to implement ecosystem management prescriptions may need to be economically viable over a wider range of piece sizes, for example. Increasing...
Effect of display size on visual attention.
Chen, I-Ping; Liao, Chia-Ning; Yeh, Shih-Hao
2011-06-01
Attention plays an important role in the design of human-machine interfaces. However, current knowledge about attention is largely based on data obtained when using devices of moderate display size. With advancement in display technology comes the need for understanding attention behavior over a wider range of viewing sizes. The effect of display size on test participants' visual search performance was studied. The participants (N = 12) performed two types of visual search tasks, that is, parallel and serial search, under three display-size conditions (16 degrees, 32 degrees, and 60 degrees). Serial, but not parallel, search was affected by display size. In the serial task, mean reaction time for detecting a target increased with the display size.
Galloway, Joel M.; Blanchard, Robert A.; Ellison, Christopher A.
2011-01-01
Most of the bedload samples had particle sizes in the 0.5 to 1 millimeter and 0.25 to 0.5 millimeter ranges from the Maple River, Wild Rice River, Rush River, Buffalo River, and Red River sites. The Rush and Lower Branch Rush Rivers also had a greater portion of larger particle sizes in the 1 to 2 millimeter range. The Sheyenne River sites had a greater portion of smaller particle sizes in the bedload in the 0.125 to 0.5 millimeter range compared to the other sites. The bed material in samples collected during the 2011 spring high-flow event demonstrated a wider distribution of particle sizes than were observed in the bedload; the coarsest material was found at the Red River near Christine and the Lower Branch Rush River and the finest material at the Sheyenne River sites.
Archaebacterial Involvement in Microbial Metal Corrosion
1990-03-19
viand /or + I A-o- - iP’ " ’ I m I I | | A more complete study using a wider range of sizes of organo groups is currently being completed to further...replaced with Dr. Boopathy, who comes from the University of Missouri. Through Dr. Rajogopal’s visit last year to work with the French-Georgia group ( Le
Wason, James M. S.; Mander, Adrian P.
2012-01-01
Two-stage designs are commonly used for Phase II trials. Optimal two-stage designs have the lowest expected sample size for a specific treatment effect, for example, the null value, but can perform poorly if the true treatment effect differs. Here we introduce a design for continuous treatment responses that minimizes the maximum expected sample size across all possible treatment effects. The proposed design performs well for a wider range of treatment effects and so is useful for Phase II trials. We compare the design to a previously used optimal design and show it has superior expected sample size properties. PMID:22651118
MAUSETH, JAMES D.
2004-01-01
• Background and Aims Shoot apical meristems (SAMs) in most seed plants are quite uniform in size and zonation, and molecular genetic studies of Arabidopsis and other model plants are revealing details of SAM morphogenesis. Some cacti have SAMs much larger than those of A. thaliana and other seed plants. This study examined how SAM size affects leaf primordium (LP) size, phyllotaxy and shoot diameter. • Methods. Apices from 183 species of cacti were fixed, microtomed and studied by light microscopy. • Key Results Cactus SAM diameter varies from 93 to 2565 µm, the latter being 36 times wider than SAMs of A. thaliana and having a volume 45 thousand times larger. Phyllotaxy ranges from distichous to having 56 rows of leaves and is not restricted to Fibonacci numbers. Leaf primordium diameter ranges from 44 to 402 µm, each encompassing many more cells than do LP of other plants. Species with high phyllotaxy have smaller LP, although the correlation is weak. There is almost no correlation between SAM diameter and LP size, but SAM diameter is strongly correlated with shoot diameter, with shoots being about 189·5 times wider than SAMs. • Conclusions Presumably, genes such as SHOOT‐MERISTEMLESS, WUSCHEL and CLAVATA must control much larger volumes of SAM tissue in cacti than they do in A. thaliana, and genes such as PERIANTHIA might establish much more extensive fields of inhibition around LP. These giant SAMs should make it possible to more accurately map gene expression patterns relative to SAM zonation and LP sites. PMID:15145794
Beyond eruptive scenarios: assessing tephra fallout hazard from Neapolitan volcanoes.
Sandri, Laura; Costa, Antonio; Selva, Jacopo; Tonini, Roberto; Macedonio, Giovanni; Folch, Arnau; Sulpizio, Roberto
2016-04-12
Assessment of volcanic hazards is necessary for risk mitigation. Typically, hazard assessment is based on one or a few, subjectively chosen representative eruptive scenarios, which use a specific combination of eruptive sizes and intensities to represent a particular size class of eruption. While such eruptive scenarios use a range of representative members to capture a range of eruptive sizes and intensities in order to reflect a wider size class, a scenario approach neglects to account for the intrinsic variability of volcanic eruptions, and implicitly assumes that inter-class size variability (i.e. size difference between different eruptive size classes) dominates over intra-class size variability (i.e. size difference within an eruptive size class), the latter of which is treated as negligible. So far, no quantitative study has been undertaken to verify such an assumption. Here, we adopt a novel Probabilistic Volcanic Hazard Analysis (PVHA) strategy, which accounts for intrinsic eruptive variabilities, to quantify the tephra fallout hazard in the Campania area. We compare the results of the new probabilistic approach with the classical scenario approach. The results allow for determining whether a simplified scenario approach can be considered valid, and for quantifying the bias which arises when full variability is not accounted for.
Beyond eruptive scenarios: assessing tephra fallout hazard from Neapolitan volcanoes
Sandri, Laura; Costa, Antonio; Selva, Jacopo; Tonini, Roberto; Macedonio, Giovanni; Folch, Arnau; Sulpizio, Roberto
2016-01-01
Assessment of volcanic hazards is necessary for risk mitigation. Typically, hazard assessment is based on one or a few, subjectively chosen representative eruptive scenarios, which use a specific combination of eruptive sizes and intensities to represent a particular size class of eruption. While such eruptive scenarios use a range of representative members to capture a range of eruptive sizes and intensities in order to reflect a wider size class, a scenario approach neglects to account for the intrinsic variability of volcanic eruptions, and implicitly assumes that inter-class size variability (i.e. size difference between different eruptive size classes) dominates over intra-class size variability (i.e. size difference within an eruptive size class), the latter of which is treated as negligible. So far, no quantitative study has been undertaken to verify such an assumption. Here, we adopt a novel Probabilistic Volcanic Hazard Analysis (PVHA) strategy, which accounts for intrinsic eruptive variabilities, to quantify the tephra fallout hazard in the Campania area. We compare the results of the new probabilistic approach with the classical scenario approach. The results allow for determining whether a simplified scenario approach can be considered valid, and for quantifying the bias which arises when full variability is not accounted for. PMID:27067389
Ultrafast and Wide Range Analysis of DNA Molecules Using Rigid Network Structure of Solid Nanowires
Rahong, Sakon; Yasui, Takao; Yanagida, Takeshi; Nagashima, Kazuki; Kanai, Masaki; Klamchuen, Annop; Meng, Gang; He, Yong; Zhuge, Fuwei; Kaji, Noritada; Kawai, Tomoji; Baba, Yoshinobu
2014-01-01
Analyzing sizes of DNA via electrophoresis using a gel has played an important role in the recent, rapid progress of biology and biotechnology. Although analyzing DNA over a wide range of sizes in a short time is desired, no existing electrophoresis methods have been able to fully satisfy these two requirements. Here we propose a novel method using a rigid 3D network structure composed of solid nanowires within a microchannel. This rigid network structure enables analysis of DNA under applied DC electric fields for a large DNA size range (100 bp–166 kbp) within 13 s, which are much wider and faster conditions than those of any existing methods. The network density is readily varied for the targeted DNA size range by tailoring the number of cycles of the nanowire growth only at the desired spatial position within the microchannel. The rigid dense 3D network structure with spatial density control plays an important role in determining the capability for analyzing DNA. Since the present method allows the spatial location and density of the nanostructure within the microchannels to be defined, this unique controllability offers a new strategy to develop an analytical method not only for DNA but also for other biological molecules. PMID:24918865
Ultrafast and Wide Range Analysis of DNA Molecules Using Rigid Network Structure of Solid Nanowires
NASA Astrophysics Data System (ADS)
Rahong, Sakon; Yasui, Takao; Yanagida, Takeshi; Nagashima, Kazuki; Kanai, Masaki; Klamchuen, Annop; Meng, Gang; He, Yong; Zhuge, Fuwei; Kaji, Noritada; Kawai, Tomoji; Baba, Yoshinobu
2014-06-01
Analyzing sizes of DNA via electrophoresis using a gel has played an important role in the recent, rapid progress of biology and biotechnology. Although analyzing DNA over a wide range of sizes in a short time is desired, no existing electrophoresis methods have been able to fully satisfy these two requirements. Here we propose a novel method using a rigid 3D network structure composed of solid nanowires within a microchannel. This rigid network structure enables analysis of DNA under applied DC electric fields for a large DNA size range (100 bp-166 kbp) within 13 s, which are much wider and faster conditions than those of any existing methods. The network density is readily varied for the targeted DNA size range by tailoring the number of cycles of the nanowire growth only at the desired spatial position within the microchannel. The rigid dense 3D network structure with spatial density control plays an important role in determining the capability for analyzing DNA. Since the present method allows the spatial location and density of the nanostructure within the microchannels to be defined, this unique controllability offers a new strategy to develop an analytical method not only for DNA but also for other biological molecules.
Development of Portable Aerosol Mobility Spectrometer for Personal and Mobile Aerosol Measurement
Kulkarni, Pramod; Qi, Chaolong; Fukushima, Nobuhiko
2017-01-01
We describe development of a Portable Aerosol Mobility Spectrometer (PAMS) for size distribution measurement of submicrometer aerosol. The spectrometer is designed for use in personal or mobile aerosol characterization studies and measures approximately 22.5 × 22.5 × 15 cm and weighs about 4.5 kg including the battery. PAMS uses electrical mobility technique to measure number-weighted particle size distribution of aerosol in the 10–855 nm range. Aerosol particles are electrically charged using a dual-corona bipolar corona charger, followed by classification in a cylindrical miniature differential mobility analyzer. A condensation particle counter is used to detect and count particles. The mobility classifier was operated at an aerosol flow rate of 0.05 L/min, and at two different user-selectable sheath flows of 0.2 L/min (for wider size range 15–855 nm) and 0.4 L/min (for higher size resolution over the size range of 10.6–436 nm). The instrument was operated in voltage stepping mode to retrieve the size distribution, which took approximately 1–2 minutes, depending on the configuration. Sizing accuracy and resolution were probed and found to be within the 25% limit of NIOSH criterion for direct-reading instruments (NIOSH 2012). Comparison of size distribution measurements from PAMS and other commercial mobility spectrometers showed good agreement. The instrument offers unique measurement capability for on-person or mobile size distribution measurements of ultrafine and nanoparticle aerosol. PMID:28413241
Linkage between canopy water storage and drop size distributions of leaf drips
NASA Astrophysics Data System (ADS)
Nanko, Kazuki; Watanabe, Ai; Hotta, Norifumi; Suzuki, Masakazu
2013-04-01
Differences in drop size distribution (DSD) of leaf drips among tree species have been estimated and physically interpreted to clarify the leaf drip generation process. Leaf drip generation experiments for nine species were conducted in an indoor location without foliage vibration using an automatic mist spray. Broad-leaved species produced a similar DSD among species whose leaves had a matte surface and a second similar DSD among species whose leaves had a coated surface. The matte broad leaves produced a larger and wider range of DSDs than the coated broad leaves. Coated coniferous needles had a wider range of DSDs than the coated broad leaves and different DSDs were observed for different species. The species with shorter dense needles generated a larger DSD. The leaf drip diameter was calculated through the estimation of a state of equilibrium of a hanging drop on the leaves based on physical theory. The calculations indicated that the maximum diameter of leaf drips was determined by the contact angle, and the range of DSDs was determined by the variation in contact length and the contact diameter at the hanging points. The results revealed that leaf drip DSD changed due to variations in leaf hydrophobicity, leaf roughness, leaf geometry and leaf inclination among the different tree species. This study allows the modelization of throughfall DSD. Furthermore, it indicates the possibility of interpreting canopy water processes from canopy water storage to drainage through the contact angle and leaf drip DSD. The part of this study is published in Nanko et al. (2013, Agric. Forest. Meteorol. 169, 74-84).
New families of carbon gels based on natural resources
NASA Astrophysics Data System (ADS)
Szczurek, Andrzej; Amaral-Labat, Gisele; Fierro, Vanessa; Pizzi, Antonio; Celzard, Alain
2013-03-01
Carbon gels are versatile materials which can be used for many applications. They are extremely expensive, because generally prepared from resorcinol - formaldehyde (RF) resins first gelled and next dried with supercritical carbon dioxide. In the present work, resorcinol has been substituted partly or completely by tannins, a family of molecules extracted from mimosa tree barks. Tannins are natural, non-toxic products, typically thirty times cheaper than resorcinol. Their chemical resemblance with the latter makes them be often called natural resorcinol. Using tannins not only substantially decreases the cost but also allows preparing materials in a much wider range of pHs than that usually employed for RF gels. Consequently the main pore size and the fraction of given families of pores, controlling the carbon gels' properties, are tuned in an easier way, and a much wider range of pore structures is obtained. Finally, two alternative ways of drying are suggested for further decreasing the cost: freeze-drying and supercritical drying in acetone. Both are shown to lead, in some conditions described below, to materials having similar characteristics to those of expensive RF carbon aerogels previously dried in supercritical CO2.
Shigeta, Masaya; Watanabe, Takayuki
2016-03-07
A computational investigation using a unique model and a solution algorithm was conducted, changing only the saturation pressure of one material artificially during nanopowder formation in thermal plasma fabrication, to highlight the effects of the saturation pressure difference between a metal and silicon. The model can not only express any profile of particle size-composition distribution for a metal-silicide nanopowder even with widely ranging sizes from sub-nanometers to a few hundred nanometers, but it can also simulate the entire growth process involving binary homogeneous nucleation, binary heterogeneous co-condensation, and coagulation among nanoparticles with different compositions. Greater differences in saturation pressures cause a greater time lag for co-condensation of two material vapors during the collective growth of the metal-silicide nanopowder. The greater time lag for co-condensation results in a wider range of composition of the mature nanopowder.
A comparison of certain methods of measuring ranges of small mammals
Stickel, L.F.
1954-01-01
SUMMARY: A comparison is made of different methods of determining size of home range from grid trapping data. Studies of artificial populations show that a boundary strip method of measuring area and an adjusted range length give sizes closer to the true range than do minimum area or observed range length methods. In simulated trapping of artificial populations, the known range size increases with successive captures until a level is reached that approximates the true range. The same general pattern is followed whether traps are visited at random or traps nearer the center of the range are favored; but when central traps are favored the curve levels more slowly. Range size is revealed with fewer captures when traps are far apart than when they are close together. The curve levels more slowly for oblong ranges than for circular ranges of the same area. Fewer captures are required to determine range length than to determine range area. Other examples of simulated trapping in artificial populations are used to provide measurements of distances from the center of activity and distances between successive captures. These are compared with similar measurements taken from Peromyscus trapping data. The similarity of range sizes found in certain field comparisons of area trapping, colored scat collections, and trailing is cited. A comparison of home range data obtained by area trapping and nest box studies is discussed. It is shown that when traps are set too far apart to include two or more in the range of each animal, calculation of average range size gives biased results. The smaller ranges are not expressed and cannot be included in the averages. The result is that range estimates are smaller at closer spacings and greater at wider spacings, purely as a result of these erroneous calculations and not reflecting any varying behavior of the animals. The problem of variation in apparent home range with variation in trap spacing is considered further by trapping in an artificial population. It is found that trap spacing can alter the apparent size of range even when biological factors are excluded and trap visiting is random. The desirability of excluding travels outside the normal range from home range calculations is discussed. Effects of varying the trapping plan by setting alternate rows of traps, or setting two traps per site, are discussed briefly.
Sizing of single evaporating droplet with Near-Forward Elastic Scattering Spectroscopy
NASA Astrophysics Data System (ADS)
Woźniak, M.; Jakubczyk, D.; Derkachov, G.; Archer, J.
2017-11-01
We have developed an optical setup and related numerical models to study evolution of single evaporating micro-droplets by analysis of their spectral properties. Our approach combines the advantages of the electrodynamic trapping with the broadband spectral analysis with the supercontinuum laser illumination. The elastically scattered light within the spectral range of 500-900 nm is observed by a spectrometer placed at the near-forward scattering angles between 4.3 ° and 16.2 ° and compared with the numerically generated lookup table of the broadband Mie scattering. Our solution has been successfully applied to infer the size evolution of the evaporating droplets of pure liquids (diethylene and ethylene glycol) and suspensions of nanoparticles (silica and gold nanoparticles in diethylene glycol), with maximal accuracy of ± 25 nm. The obtained results have been compared with the previously developed sizing techniques: (i) based on the analysis of the Mie scattering images - the Mie Scattering Lookup Table Method and (ii) the droplet weighting. Our approach provides possibility to handle levitating objects with much larger size range (radius from 0.5 μm to 30 μm) than with the use of optical tweezers (typically radius below 8 μm) and analyse them with much wider spectral range than with commonly used LED sources.
Navigating aerial transects with a laptop computer
Anthony, R. Michael; Stehn, R.A.
1994-01-01
SUMMARY: A comparison is made of different methods of determining size of home range from grid trapping data. Studies of artificial populations show that a boundary strip method of measuring area and an adjusted range length give sizes closer to the true range than do minimum area or observed range length methods. In simulated trapping of artificial populations, the known range size increases with successive captures until a level is reached that approximates the true range. The same general pattern is followed whether traps are visited at random or traps nearer the center of the range are favored; but when central traps are favored the curve levels more slowly. Range size is revealed with fewer captures when traps are far apart than when they are close together. The curve levels more slowly for oblong ranges than for circular ranges of the same area. Fewer captures are required to determine range length than to determine range area. Other examples of simulated trapping in artificial populations are used to provide measurements of distances from the center of activity and distances between successive captures. These are compared with similar measurements taken from Peromyscus trapping data. The similarity of range sizes found in certain field comparisons of area trapping, colored scat collections, and trailing is cited. A comparison of home range data obtained by area trapping and nest box studies is discussed. It is shown that when traps are set too far apart to include two or more in the range of each animal, calculation of average range size gives biased results. The smaller ranges are not expressed and cannot be included in the averages. The result is that range estimates are smaller at closer spacings and greater at wider spacings, purely as a result of these erroneous calculations and not reflecting any varying behavior of the animals. The problem of variation in apparent home range with variation in trap spacing is considered further by trapping in an artificial population. It is found that trap spacing can alter the apparent size of range even when biological factors are excluded and trap visiting is random. The desirability of excluding travels outside the normal range from home range calculations is discussed. Effects of varying the trapping plan by setting alternate rows of traps, or setting two traps per site, are discussed briefly.
Spatiotemporal chaos of fractional order logistic equation in nonlinear coupled lattices
NASA Astrophysics Data System (ADS)
Zhang, Ying-Qian; Wang, Xing-Yuan; Liu, Li-Yan; He, Yi; Liu, Jia
2017-11-01
We investigate a new spatiotemporal dynamics with fractional order differential logistic map and spatial nonlinear coupling. The spatial nonlinear coupling features such as the higher percentage of lattices in chaotic behaviors for most of parameters and none periodic windows in bifurcation diagrams are held, which are more suitable for encryptions than the former adjacent coupled map lattices. Besides, the proposed model has new features such as the wider parameter range and wider range of state amplitude for ergodicity, which contributes a wider range of key space when applied in encryptions. The simulations and theoretical analyses are developed in this paper.
The influence of feminist ascription on judgements of women's physical attractiveness.
Swami, Viren; Salem, Natalie; Furnham, Adrian; Tovée, Martin J
2008-06-01
The present study examined the effect of feminist ascription on perceptions of the physical attractiveness of women ranging in body mass index (BMI). One-hundred and twenty-nine women who self-identified as feminists and 132 who self-identified as non-feminists rated a series of 10 images of women that varied in BMI from emaciated to obese. Results showed no significant differences between feminist and non-feminists in the figure they considered to be maximally attractive. However, feminists were more likely to positively perceive a wider range of body sizes than non-feminists. These results are discussed in relation to possible protective factors against the internalisation of the thin ideal and body objectification.
NASA Astrophysics Data System (ADS)
El-Taibany, W. F.; El-Siragy, N. M.; Behery, E. E.; Elbendary, A. A.; Taha, R. M.
2018-05-01
The propagation characteristics of dust acoustic waves (DAWs) in a dusty plasma consisting of variable size dust grains, hybrid Cairns-Tsallis-distributed electrons, and nonthermal ions are studied. The charging of the dust grains is described by the orbital-motion-limited theory and the size of the dust grains obeys the power law dust size distribution. To describe the nonlinear propagation of the DAWs, a Zakharov-Kuznetsov equation is derived using a reductive perturbation method. It is found that the nonthermal and nonextensive parameters influence the main properties of DAWs. Moreover, our results reveal that the rarefactive waves can propagate mainly in the proposed plasma model while compressive waves can be detected for a very small range of the distribution parameters of plasma species, and the DAWs are faster and wider for smaller size dust grains. Applications of the present results to dusty plasma observations are briefly discussed.
NASA Technical Reports Server (NTRS)
Lieneweg, Udo; Hannaman, David J.
1987-01-01
A quasi-two-dimensional analytical model is developed to account for vertical and horizontal current flow in and adjacent to a square ohmic contact between a metal and a thin semiconducting strip which is wider than the contact. The model includes side taps to the contact area for voltage probing and relates the 'apparent' interfacial resistivity to the (true) interfacial resistivity, the sheet resistance of the semiconducting layer, the contact size, and the width of the 'flange' around the contact. This relation is checked against numerical simulations. With the help of the model, interfacial resistivities of ohmic contacts to GaAs were extracted and found independent of contact size in the range of 1.5-10 microns.
Sizes and locations of coronal mass ejections - SMM observations from 1980 and 1984-1989
NASA Technical Reports Server (NTRS)
Hundhausen, A. J.
1993-01-01
A statistical description of the sizes and locations of 1209 mass ejections observed with the SMM coronagraph/polarimeter in 1980 and 1984-1989 is presented. The average width of the coronal mass ejections detected with this instrument was close to 40 deg in angle for the entire period of SMM observations. No evidence was found for a significant change in mass ejection widths as reported by Howard et al. (1986). There is clear evidence for changes in the latitude distribution of mass ejections over this epoch. Mass ejections occurred over a much wider range of latitudes at the times of high solar activity (1980 and 1989) than at times of low activity (1985-1986).
Daly, Ryan; Froneman, Pierre W; Smale, Malcolm J
2013-01-01
As apex predators, sharks play an important role shaping their respective marine communities through predation and associated risk effects. Understanding the predatory dynamics of sharks within communities is, therefore, necessary to establish effective ecologically based conservation strategies. We employed non-lethal sampling methods to investigate the feeding ecology of bull sharks (Carcharhinus leucas) using stable isotope analysis within a subtropical marine community in the southwest Indian Ocean. The main objectives of this study were to investigate and compare the predatory role that sub-adult and adult bull sharks play within a top predatory teleost fish community. Bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and relatively enriched range of δ(13)C values relative to the local marine community. This suggests that bull sharks forage from a more diverse range of δ(13)C sources over a wider geographical range than the predatory teleost community. Adult bull sharks appeared to exhibit a shift towards consistently higher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Although predatory teleost fish are also capable of substantial migrations, bull sharks may have the ability to exploit a more diverse range of habitats and appeared to prey on a wider diversity of larger prey. This suggests that bull sharks play an important predatory role within their respective marine communities and adult sharks in particular may shape and link ecological processes of a variety of marine communities over a broad range.
Daly, Ryan; Froneman, Pierre W.; Smale, Malcolm J.
2013-01-01
As apex predators, sharks play an important role shaping their respective marine communities through predation and associated risk effects. Understanding the predatory dynamics of sharks within communities is, therefore, necessary to establish effective ecologically based conservation strategies. We employed non-lethal sampling methods to investigate the feeding ecology of bull sharks (Carcharhinus leucas) using stable isotope analysis within a subtropical marine community in the southwest Indian Ocean. The main objectives of this study were to investigate and compare the predatory role that sub-adult and adult bull sharks play within a top predatory teleost fish community. Bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and relatively enriched range of δ13C values relative to the local marine community. This suggests that bull sharks forage from a more diverse range of δ13C sources over a wider geographical range than the predatory teleost community. Adult bull sharks appeared to exhibit a shift towards consistently higher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Although predatory teleost fish are also capable of substantial migrations, bull sharks may have the ability to exploit a more diverse range of habitats and appeared to prey on a wider diversity of larger prey. This suggests that bull sharks play an important predatory role within their respective marine communities and adult sharks in particular may shape and link ecological processes of a variety of marine communities over a broad range. PMID:24205168
NASA Astrophysics Data System (ADS)
Frangoulis, Constantin; Grigoratou, Maria; Zoulias, Theodore; Hannides, Cecelia C. S.; Pantazi, Maria; Psarra, Stella; Siokou, Ioanna
2017-10-01
Although metazooplankton includes a wide size range of organisms, our knowledge is essentially based on mesozooplankton. A first estimation of the metazooplankton standing stock in a Mediterranean area, and of its size fractions and functional groups are provided by combining data out of three nets with different mesh sizes (45, 200 and 500 μm). Data were collected along a gradient of oligotrophy in the frontal area created, where the waters of Black Sea origin meet those of Levantine Sea origin (Northeast Aegean Sea, Eastern Mediterranean). Metazooplankton biomass was dominated by mesozooplankton (0.2-2 mm), while meso- and microzooplankton (<0.2 mm) shared dominance of abundance. Copepods dominated both in abundance and biomass and were followed by nauplii in abundance and gelatinous carnivores or decapod-euphausiid larvae in biomass. The spatiotemporal variability of metazoans stock, biomass-size spectra linearity, carnivorous group contribution and copepod diversity, supported that metazooplankton tends to recede from steady-state when approaching less oligotrophic dynamic areas (such as fronts) or dynamic periods (such as the spring bloom). The need and the difficulties of obtaining a larger picture from a wider size range of metazoans for understanding the role of zooplankton are stressed.
Zheng, Zhi; Gong, Da-Jie; Sun, Cheng-Xiang; Li, Xiao-Jun; Li, Wan-Jiang
2014-09-01
Altitudinal patterns of species richness and species range size and their underlying mechanisms have long been a key topic in biogeography and biodiversity research. Rapoport's rule stated that the species richness gradually declined with the increasing altitude, while the species ranges became larger. Using altitude-distribution database from Xiaolongshan Reverse, this study explored the altitudinal patterns of vascular plant species richness and species range in Qinling Xiaolongshan Reserve, and examined the relationships between species richness and their distributional middle points in altitudinal bands for different fauna, taxonomic units and growth forms and tested the Rapoport's rule by using Stevens' method, Pagel's method, mid-point method and cross-species method. The results showed that the species richness of vascular plants except small-range species showed a unimodal pattern along the altitude in Qinling Xiaolongshan Reserve and the highest proportion of small-range species was found at the lower altitudinal bands and at the higher altitudinal bands. Due to different assemblages and examining methods, the relationships between species distributing range sizes and the altitudes were different. Increasing taxonomic units was easier to support Rapoport's rule, which was related to niche differences that the different taxonomic units occupied. The mean species range size of angiosperms showed a unimodal pattern along the altitude, while those of the gymnosperms and pteridophytes were unclearly regular. The mean species range size of the climbers was wider with the increasing altitude, while that of the shrubs which could adapt to different environmental situations was not sensitive to the change of altitude. Pagel's method was easier to support the Rapoport's rule, and then was Steven's method. On the contrary, due to the mid-domain effect, the results of the test by using the mid-point method showed that the mean species range size varied in a unimodal pattern along the altitude, which didn't support the Rapoport's rule, and because of the scatter-spot impact, the explanatory power of the cross-species method was much lower.
Phase Equilibrium of TiO2 Nanocrystals in Flame-Assisted Chemical Vapor Deposition.
Liu, Changran; Camacho, Joaquin; Wang, Hai
2018-01-19
Nano-scale titanium oxide (TiO 2 ) is a material useful for a wide range of applications. In a previous study, we showed that TiO 2 nanoparticles of both rutile and anatase crystal phases could be synthesized over the size range of 5 to 20 nm in flame-assisted chemical vapor deposition. Rutile was unexpectedly dominant in oxygen-lean synthesis conditions, whereas anatase is the preferred phase in oxygen-rich gases. The observation is in contrast to the 14 nm rutile-anatase crossover size derived from the existing crystal-phase equilibrium model. In the present work, we made additional measurements over a wider range of synthesis conditions; the results confirm the earlier observations. We propose an improved model for the surface energy that considers the role of oxygen desorption at high temperatures. The model successfully explains the observations made in the current and previous work. The current results provide a useful path to designing flame-assisted chemical vapor deposition of TiO 2 nanocrystals with controllable crystal phases. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Han, Chang-Hee; Lim, Jeong-Hwan; Lee, Jun-Hak; Kim, Kangsan; Im, Chang-Hwan
2016-01-01
It has frequently been reported that some users of conventional neurofeedback systems can experience only a small portion of the total feedback range due to the large interindividual variability of EEG features. In this study, we proposed a data-driven neurofeedback strategy considering the individual variability of electroencephalography (EEG) features to permit users of the neurofeedback system to experience a wider range of auditory or visual feedback without a customization process. The main idea of the proposed strategy is to adjust the ranges of each feedback level using the density in the offline EEG database acquired from a group of individuals. Twenty-two healthy subjects participated in offline experiments to construct an EEG database, and five subjects participated in online experiments to validate the performance of the proposed data-driven user feedback strategy. Using the optimized bin sizes, the number of feedback levels that each individual experienced was significantly increased to 139% and 144% of the original results with uniform bin sizes in the offline and online experiments, respectively. Our results demonstrated that the use of our data-driven neurofeedback strategy could effectively increase the overall range of feedback levels that each individual experienced during neurofeedback training.
Lim, Jeong-Hwan; Lee, Jun-Hak; Kim, Kangsan
2016-01-01
It has frequently been reported that some users of conventional neurofeedback systems can experience only a small portion of the total feedback range due to the large interindividual variability of EEG features. In this study, we proposed a data-driven neurofeedback strategy considering the individual variability of electroencephalography (EEG) features to permit users of the neurofeedback system to experience a wider range of auditory or visual feedback without a customization process. The main idea of the proposed strategy is to adjust the ranges of each feedback level using the density in the offline EEG database acquired from a group of individuals. Twenty-two healthy subjects participated in offline experiments to construct an EEG database, and five subjects participated in online experiments to validate the performance of the proposed data-driven user feedback strategy. Using the optimized bin sizes, the number of feedback levels that each individual experienced was significantly increased to 139% and 144% of the original results with uniform bin sizes in the offline and online experiments, respectively. Our results demonstrated that the use of our data-driven neurofeedback strategy could effectively increase the overall range of feedback levels that each individual experienced during neurofeedback training. PMID:27631005
Dependence of the forward light scattering on the refractive index of particles
NASA Astrophysics Data System (ADS)
Guo, Lufang; Shen, Jianqi
2018-05-01
In particle sizing technique based on forward light scattering, the scattered light signal (SLS) is closely related to the relative refractive index (RRI) of the particles to the surrounding, especially when the particles are transparent (or weakly absorbent) and the particles are small in size. The interference between the diffraction (Diff) and the multiple internal reflections (MIR) of scattered light can lead to the oscillation of the SLS on RRI and the abnormal intervals, especially for narrowly-distributed small particle systems. This makes the inverse problem more difficult. In order to improve the inverse results, Tikhonov regularization algorithm with B-spline functions is proposed, in which the matrix element is calculated for a range of particle sizes instead using the mean particle diameter of size fractions. In this way, the influence of abnormal intervals on the inverse results can be eliminated. In addition, for measurements on narrowly distributed small particles, it is suggested to detect the SLS in a wider scattering angle to include more information.
Memory-based snowdrift game on a square lattice
NASA Astrophysics Data System (ADS)
Shu, Feng; Liu, Xingwen; Fang, Kai; Chen, Hao
2018-04-01
Spatial reciprocity is an effective way widely accepted to facilitate cooperation. In the case of snowdrift game, some researches showed that spatial reciprocity inhibits cooperation for a very wide range of cost-to-benefit ratio r. However, some other researches found that based on the spatial reciprocity, a wider range of r is helpful to achieve a high cooperation level. Thus, how to enlarge the range of r for the purpose of promoting cooperation becomes a hot topic recently. This paper proposes a new memory-based method, in which each individual compares with its own previous payoffs to find out the maximal one as virtual payoff and then randomly compares with one of its neighbours to obtain the optimal strategy according to the given updating rules. It shows the positive effect of spatial reciprocity in the context of memory. Specifically, in this situation, not only the lower ratio can appear a high cooperation level, but also the larger ratio r can emerge a high cooperation level. That is, an expected cooperation level can be achieved simultaneously for small and large r. Furthermore, the scenarios of both constant-size memory and size-varying memory are investigated. An interesting phenomenon is discovered that the cooperation level drops down gradually as the memory size increases.
NASA Astrophysics Data System (ADS)
Garvie, Laurence A. J.; Baumgardner, Grant; Buseck, Peter R.
2008-05-01
Carbonaceous nanoglobules are ubiquitous in carbonaceous chondrite (CC) meteorites. The Tagish Lake (C2) meteorite is particularly intriguing in containing an abundance of nanoglobules, with a wider range of forms and sizes than encountered in other CC meteorites. Previous studies by transmission electron microscopy (TEM) have provided a wealth of information on chemistry and structure. In this study low voltage scanning electron microscopy (SEM) was used to characterize the globule forms and external structures. The internal structure of the globules was investigated after sectioning by focused ion beam (FIB) milling. The FIB-SEM analysis shows that the globules range from solid to hollow. Some hollow globules show a central open core, with adjoining smaller cores. The FIB with an SEM is a valuable tool for the analysis of extraterrestrial materials, even of sub-micron-sized "soft" carbonaceous particles. The rapid site-specific cross-sectioning capabilities of the FIB allow the preservation of the internal morphology of the nanoglobules, with minimal damage or alteration of the unsectioned areas.
Studies of ionic current rectification using polyethyleneimines coated glass nanopipettes.
Liu, Shujuan; Dong, Yitong; Zhao, Wenbo; Xie, Xiang; Ji, Tianrong; Yin, Xiaohong; Liu, Yun; Liang, Zhongwei; Momotenko, Dmitry; Liang, Dehai; Girault, Hubert H; Shao, Yuanhua
2012-07-03
The modification of glass nanopipettes with polyethyleneimines (PEIs) has been successfully achieved by a relatively simple method, and the smallest tip opening is around 3 nm. Thus, in a much wider range of glass pipettes with radii from several nanometers to a few micrometers, the ion current rectification (ICR) phenomenon has been observed. The influences of different KCl concentrations, pH values, and tip radii on the ICR are investigated in detail. The sizes of PEIs have been determined by dynamic light scattering, and the effect of the sizes of PEIs for the modification, especially for a few nanometer-pipettes in radii, is also discussed. These findings systemically confirm and complement the theoretical model and provide a platform for possible selectively molecular detection and mimic biological ion channels.
Sound absorption of a new oblique-section acoustic metamaterial with nested resonator
NASA Astrophysics Data System (ADS)
Gao, Nansha; Hou, Hong; Zhang, Yanni; Wu, Jiu Hui
2018-02-01
This study designs and investigates high-efficiency sound absorption of new oblique-section nested resonators. Impedance tube experiment results show that different combinations of oblique-section nest resonators have tunable low-frequency bandwidth characteristics. The sound absorption mechanism is due to air friction losses in the slotted region and the sample structure resonance. The acousto-electric analogy model demonstrates that the sound absorption peak and bandwidth can be modulated over an even wider frequency range by changing the geometric size and combinations of structures. The proposed structure can be easily fabricated and used in low-frequency sound absorption applications.
NASA Technical Reports Server (NTRS)
Hunt, Mitchell; Sayyah, Rana; Mitchell, Cody; Laws, Crystal; MacLeod, Todd C.; Ho, Fat D.
2013-01-01
Collected data for both common-source and common-gate amplifiers is presented in this paper. Characterizations of the two amplifier circuits using metal-ferroelectric-semiconductor field effect transistors (MFSFETs) are developed with wider input frequency ranges and varying device sizes compared to earlier characterizations. The effects of the ferroelectric layer's capacitance and variation load, quiescent point, or input signal on each circuit are discussed. Comparisons between the MFSFET and MOSFET circuit operation and performance are discussed at length as well as applications and advantages for the MFSFETs.
Computational and Mathematical Modeling of Coupled Superconducting Quantum Interference Devices
NASA Astrophysics Data System (ADS)
Berggren, Susan Anne Elizabeth
This research focuses on conducting an extensive computational investigation and mathematical analysis into the average voltage response of arrays of Superconducting Quantum Interference Devices (SQUIDs). These arrays will serve as the basis for the development of a sensitive, low noise, significantly lower Size, Weight and Power (SWaP) antenna integrated with Low-Noise Amplifier (LNA) using the SQUID technology. The goal for this antenna is to be capable of meeting all requirements for Guided Missile Destroyers (DDG) 1000 class ships for Information Operations/Signals Intelligence (IO/SIGINT) applications in Very High Frequency/Ultra High Frequency (V/UHF) bands. The device will increase the listening capability of receivers by moving technology into a new regime of energy detection allowing wider band, smaller size, more sensitive, stealthier systems. The smaller size and greater sensitivity will allow for ships to be “de-cluttered” of their current large dishes and devices, replacing everything with fewer and smaller SQUID antenna devices. The fewer devices present on the deck of a ship, the more invisible the ship will be to enemy forces. We invent new arrays of SQUIDs, optimized for signal detection with very high dynamic range and excellent spur-free dynamic range, while maintaining extreme small size (and low radar cross section), wide bandwidth, and environmentally noise limited sensitivity, effectively shifting the bottle neck of receiver systems forever away from the antenna itself deeper into the receiver chain. To accomplish these goals we develop and validate mathematical models for different designs of SQUID arrays and use them to invent a new device and systems design. This design is capable of significantly exceeding, per size weight and power, state-of-the-art receiver system measures of performance, such as bandwidth, sensitivity, dynamic range, and spurious-free dynamic range.
Growth-direction dependence of steady-state Saffman-Taylor flow in an anisotropic Hele-Shaw cell
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCloud, K.V.; Maher, J.V.
1996-08-01
Selection of steady-state fingers has been measured in a Hele-Shaw cell perturbed by having a square lattice etched onto one of the plates. Flows at different orientations {theta} between the direction of flow and the lattice axes have been studied, in a wide range of observable tip velocities where the perturbation was made microscopic in the sense that the capillary length of the flow was much greater than the etched lattice cell size. The full range of dynamically interesting angles for the square lattice was examined, and above a threshold, the microscopic perturbation always results in wider fingers than aremore » selected in the unperturbed case. There is some dependence of the width of the fingers on the orientation of the flow, with fingers at {theta}=0{degree} being the widest with respect to the unperturbed fingers, and fingers at 45{degree} being the least wide, although still wider than the unperturbed fingers. All observed solutions are symmetric, centered in the channel, and have the relation between tip-curvature and finger width expected of members of the Saffman-Taylor family of solutions. Selected solutions narrow again at tip velocities where the perturbation can no longer be considered microscopic. {copyright} {ital 1996 The American Physical Society.}« less
tRNA acceptor stem and anticodon bases form independent codes related to protein folding
Carter, Charles W.; Wolfenden, Richard
2015-01-01
Aminoacyl-tRNA synthetases recognize tRNA anticodon and 3′ acceptor stem bases. Synthetase Urzymes acylate cognate tRNAs even without anticodon-binding domains, in keeping with the possibility that acceptor stem recognition preceded anticodon recognition. Representing tRNA identity elements with two bits per base, we show that the anticodon encodes the hydrophobicity of each amino acid side-chain as represented by its water-to-cyclohexane distribution coefficient, and this relationship holds true over the entire temperature range of liquid water. The acceptor stem codes preferentially for the surface area or size of each side-chain, as represented by its vapor-to-cyclohexane distribution coefficient. These orthogonal experimental properties are both necessary to account satisfactorily for the exposed surface area of amino acids in folded proteins. Moreover, the acceptor stem codes correctly for β-branched and carboxylic acid side-chains, whereas the anticodon codes for a wider range of such properties, but not for size or β-branching. These and other results suggest that genetic coding of 3D protein structures evolved in distinct stages, based initially on the size of the amino acid and later on its compatibility with globular folding in water. PMID:26034281
Møller, Anders P.
2017-01-01
Understanding temporal variability in population size is important for conservation biology because wide population fluctuations increase the risk of extinction. Previous studies suggested that certain ecological, demographic, life-history and genetic characteristics of species might be related to the degree of their population fluctuations. We checked whether that was the case in a large sample of 231 European breeding bird species while taking a number of potentially confounding factors such as population trends or similarities among species due to common descent into account. When species-specific characteristics were analysed one by one, the magnitude of population fluctuations was positively related to coloniality, habitat, total breeding range, heterogeneity of breeding distribution and natal dispersal, and negatively related to urbanisation, abundance, relative number of subspecies, parasitism and proportion of polymorphic loci. However, when abundance (population size) was included in the analyses of the other parameters, only coloniality, habitat, total breeding range and abundance remained significantly related to population fluctuations. The analysis including all these predictors simultaneously showed that population size fluctuated more in colonial, less abundant species with larger breeding ranges. Other parameters seemed to be related to population fluctuations only because of their association with abundance or coloniality. The unexpected positive relationship between population fluctuations and total breeding range did not seem to be mediated by abundance. The link between population fluctuations and coloniality suggests a previously unrecognized cost of coloniality. The negative relationship between population size and population fluctuations might be explained by at least three types of non-mutually exclusive stochastic processes: demographic, environmental and genetic stochasticity. Measurement error in population indices, which was unknown, may have contributed to the negative relationship between population size and fluctuations, but apparently only to a minor extent. The association between population size and fluctuations suggests that populations might be stabilized by increasing population size. PMID:28253345
2012-05-10
This graphic shows the global distribution of craters that hit the giant asteroid Vesta, based on data from NASA Dawn mission. The yellow circles indicate craters of 2 miles or wider, with the size of the circles indicating the size of the crater.
Granule size control and targeting in pulsed spray fluid bed granulation.
Ehlers, Henrik; Liu, Anchang; Räikkönen, Heikki; Hatara, Juha; Antikainen, Osmo; Airaksinen, Sari; Heinämäki, Jyrki; Lou, Honxiang; Yliruusi, Jouko
2009-07-30
The primary aim of the study was to investigate the effects of pulsed liquid feed on granule size. The secondary aim was to increase knowledge of this technique in granule size targeting. Pulsed liquid feed refers to the pump changing between on- and off-positions in sequences, called duty cycles. One duty cycle consists of one on- and off-period. The study was performed with a laboratory-scale top-spray fluid bed granulator with duty cycle length and atomization pressure as studied variables. The liquid feed rate, amount and inlet air temperature were constant. The granules were small, indicating that the powder has only undergone ordered mixing, nucleation and early growth. The effect of atomizing pressure on granule size depends on inlet air relative humidity, with premature binder evaporation as a reason. The duty cycle length was of critical importance to the end product attributes, by defining the extent of intermittent drying and rewetting. By varying only the duty cycle length, it was possible to control granule nucleation and growth, with a wider granule size target range in increased relative humidity. The present study confirms that pulsed liquid feed in fluid bed granulation is a useful tool in end product particle size targeting.
Study into the correlation of dominant pore throat size and SIP relaxation frequency
NASA Astrophysics Data System (ADS)
Kruschwitz, Sabine; Prinz, Carsten; Zimathies, Annett
2016-12-01
There is currently a debate within the SIP community about the characteristic textural length scale controlling relaxation time of consolidated porous media. One idea is that the relaxation time is dominated by the pore throat size distribution or more specifically the modal pore throat size as determined in mercury intrusion capillary pressure tests. Recently new studies on inverting pore size distributions from SIP data were published implying that the relaxation mechanisms and controlling length scale are well understood. In contrast new analytical model studies based on the Marshall-Madden membrane polarization theory suggested that two relaxation processes might compete: the one along the short narrow pore (the throat) with one across the wider pore in case the narrow pores become relatively long. This paper presents a first systematically focused study into the relationship of pore throat sizes and SIP relaxation times. The generality of predicted trends is investigated across a wide range of materials differing considerably in chemical composition, specific surface and pore space characteristics. Three different groups of relaxation behaviors can be clearly distinguished. The different behaviors are related to clay content and type, carbonate content, size of the grains and the wide pores in the samples.
NASA Astrophysics Data System (ADS)
Musarudin, M.; Saripan, M. I.; Mashohor, S.; Saad, W. H. M.; Nordin, A. J.; Hashim, S.
2015-10-01
Energy window technique has been implemented in all positron emission tomography (PET) imaging protocol, with the aim to remove the unwanted low energy photons. Current practices in our institution however are performed by using default energy threshold level regardless of the weight of the patient. Phantom size, which represents the size of the patient's body, is the factor that determined the level of scatter fraction during PET imaging. Thus, the motivation of this study is to determine the optimum energy threshold level for different sizes of human-shaped phantom, to represent underweight, normal, overweight and obese patients. In this study, the scanner was modeled by using Monte Carlo code, version MCNP5. Five different sizes of elliptical-cylinder shaped of human-sized phantoms with diameter ranged from 15 to 30 cm were modeled. The tumor was modeled by a cylindrical line source filled with 1.02 MeV positron emitters at the center of the phantom. Various energy window widths, in the ranged of 10-50% were implemented to the data. In conclusion, the phantom mass volume did influence the scatter fraction within the volume. Bigger phantom caused more scattering events and thus led to coincidence counts lost. We evaluated the impact of phantom sizes on the sensitivity and visibility of the simulated models. Implementation of wider energy window improved the sensitivity of the system and retained the coincidence photons lost. Visibility of the tumor improved as an appropriate energy window implemented for the different sizes of phantom.
Black phosphorus quantum dots/attapulgite nanocomposite with enhanced photocatalytic performance
NASA Astrophysics Data System (ADS)
Li, Xiazhang; Li, Feihong; Lu, Xiaowang; Zuo, Shixiang; Zhuang, Ziheng; Yao, Chao
Novel black phosphorus quantum dots/attapulgite (BPQDs/ATP) nanocomposites were prepared via a facile hydrothermal-deposition method. TEM showed that BPQDs dispersed evenly on the surface of ATP with uniform particle size about 5nm. UV-Vis revealed that the BPQDs/ATP composite showed wider visible light absorption range as compared with pure ATP. The photocatalytic activity was evaluated by degradation of bisphenol A (BPA). Results showed that BPQDs/ATP reached 90% degradation rate under solar light irradiation for 180min. The coherent heterostructure formed by BPQDs and ATP was responsible for the enhanced photocatalytic performance, due to the sensitization effect of BPQDs and the facilitation of charges separation.
High temperature ion source for an on-line isotope separator
Mlekodaj, Ronald L.
1979-01-01
A reduced size ion source for on-line use with a cyclotron heavy-ion beam is provided. A sixfold reduction in source volume while operating with similar input power levels results in a 2000.degree. C. operating temperature. A combined target/window normally provides the reaction products for ionization while isolating the ion source plasma from the cyclotron beam line vacuum. A graphite felt catcher stops the recoiling reaction products and releases them into the plasma through diffusion and evaporation. Other target arrangements are also possible. A twenty-four hour lifetime of unattended operation is achieved, and a wider range of elements can be studied than was heretofore possible.
NASA Astrophysics Data System (ADS)
Rodríguez-Magdaleno, K. A.; Pérez-Álvarez, R.; Martínez-Orozco, J. C.; Pernas-Salomón, R.
2017-04-01
In this work the generation of an intermediate band of energy levels from multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution is reported. Within the effective mass approximation the electronic structure of a GaAs spherical quantum-dot surrounded by one, two and three shells is studied in detail using a numerically stable transfer matrix method. We found that a shells-size distribution characterized by continuously wider GaAs domains is a suitable mechanism to generate the intermediate band whose width is also dependent on the Aluminium concentration x. Our results suggest that this effective mechanism can be used for the design of wider intermediate band than reported in other quantum systems with possible solar cells enhanced performance.
Jet Noise Modeling for Suppressed and Unsuppressed Aircraft in Simulated Flight
NASA Technical Reports Server (NTRS)
Stone, James R.; Krejsa, Eugene A.; Clark, Bruce J; Berton, Jeffrey J.
2009-01-01
This document describes the development of further extensions and improvements to the jet noise model developed by Modern Technologies Corporation (MTC) for the National Aeronautics and Space Administration (NASA). The noise component extraction and correlation approach, first used successfully by MTC in developing a noise prediction model for two-dimensional mixer ejector (2DME) nozzles under the High Speed Research (HSR) Program, has been applied to dual-stream nozzles, then extended and improved in earlier tasks under this contract. Under Task 6, the coannular jet noise model was formulated and calibrated with limited scale model data, mainly at high bypass ratio, including a limited-range prediction of the effects of mixing-enhancement nozzle-exit chevrons on jet noise. Under Task 9 this model was extended to a wider range of conditions, particularly those appropriate for a Supersonic Business Jet, with an improvement in simulated flight effects modeling and generalization of the suppressor model. In the present task further comparisons are made over a still wider range of conditions from more test facilities. The model is also further generalized to cover single-stream nozzles of otherwise similar configuration. So the evolution of this prediction/analysis/correlation approach has been in a sense backward, from the complex to the simple; but from this approach a very robust capability is emerging. Also from these studies, some observations emerge relative to theoretical considerations. The purpose of this task is to develop an analytical, semi-empirical jet noise prediction method applicable to takeoff, sideline and approach noise of subsonic and supersonic cruise aircraft over a wide size range. The product of this task is an even more consistent and robust model for the Footprint/Radius (FOOTPR) code than even the Task 9 model. The model is validated for a wider range of cases and statistically quantified for the various reference facilities. The possible role of facility effects will thus be documented. Although the comparisons that can be accomplished within the limited resources of this task are not comprehensive, they provide a broad enough sampling to enable NASA to make an informed decision on how much further effort should be expended on such comparisons. The improved finalized model is incorporated into the FOOTPR code. MTC has also supported the adaptation of this code for incorporation in NASA s Aircraft Noise Prediction Program (ANOPP).
Dietary specialization is linked to reduced species durations in North American fossil canids
NASA Astrophysics Data System (ADS)
Balisi, Mairin; Casey, Corinna; Van Valkenburgh, Blaire
2018-04-01
How traits influence species persistence is a fundamental question in ecology, evolution and palaeontology. We test the relationship between dietary traits and both species duration and locality coverage over 40 million years in North American canids, a clade with considerable ecomorphological disparity and a dense fossil record. Because ecomorphological generalization-broad resource use-may enable species to withstand disturbance, we predicted that canids of average size and mesocarnivory would exhibit longer durations and wider distributions than specialized larger or smaller species. Second, because locality coverage might reflect dispersal ability and/or survivability in a range of habitats, we predicted that high coverage would correspond with longer durations. We find a nonlinear relationship between species duration and degree of carnivory: species at either end of the carnivory spectrum tend to have shorter durations than mesocarnivores. Locality coverage shows no relationship with size, diet or duration. To test whether generalization (medium size, mesocarnivory) corresponds to an adaptive optimum, we fit trait evolution models to previously generated canid phylogenies. Our analyses identify no single optimum in size or diet. Instead, the primary model of size evolution is a classic Cope's Rule increase over time, while dietary evolution does not conform to a single model.
Size of the top jet drop produced by bubble bursting
NASA Astrophysics Data System (ADS)
Berny, Alexis; Deike, Luc; Popinet, Stéphane; Seon, Thomas
2017-11-01
When a bubble is located on a liquid-air interface, it eventually bursts. First, the bubble cap shatters and produces film drops. Then, the cavity collapses, a tiny liquid jet rises and, depending on bubble radius and liquid parameters, it can eventually break-up and release the so-called jet drops. We perform numerical simulations, using the free software basilisk, to determine and discuss the regime of existence and the size of the first liquid jet droplets. We first validate the numerical scheme by comparing our results with recent experimental data. We then extend our numerical study to a wider range of control parameters in order to enrich our knowledge of the jet drops production. Finally, we show and interpret our results using a scaling law approach and basic physical arguments. This allows us to untangle the intricate roles of viscosity, gravity, and surface tension in the end pinching of the bubble bursting jet.
Samara size versus dispersal and seedling establishment in Ailanthus altissima (Miller) Swingle.
Delgado, J A; Jimenez, M D; Gomez, A
2009-03-01
We have specifically carried out a greenhouse experiment to assess relationship between samara weight and seed success. Relationship assessed as dispersal potential, germination level, germination rate and early seedling mass for the invasive species Ailanthus altissima. For this purpose, we considered two close stands as seeds source. We found no correlation between samara size and neither germination level, germination rate, nor seedling mass, but a positive correlation with samara projected area. These results suggest that samara weight is not directly related to germination, dispersal and invasion potential neither. Nevertheless, stands differed in the invasion potential of their samaras; one stand presented samaras with higher projected area per weight unit whereas the other one presented samaras that produced heavier seedlings. Whatever the origin, (genetic or environmental) of this differences it should be advantageous for a colonizing invader species such as A. altissima since it could imply a wider range of habitats susceptible to invasion.
Ortega-Mayagoitia, Elizabeth; Hernández-Martínez, Osvaldo; Ciros-Pérez, Jorge
2018-01-01
According to the Climatic Variability Hypothesis [CVH], thermal plasticity should be wider in organisms from temperate environments, but is unlikely to occur in tropical latitudes where temperature fluctuations are narrow. In copepods, food availability has been suggested as the main driver of phenotypic variability in adult size if the range of temperature change is less than 14°C. Leptodiaptomus garciai is a calanoid copepod inhabiting Lake Alchichica, a monomictic, tropical lake in Mexico that experiences regular, narrow temperature fluctuations but wide changes in phytoplankton availability. We investigated whether the seasonal fluctuations of temperature and food produce phenotypic variation in the life-history traits of this tropical species. We sampled L. garciai throughout a year and measured female size, egg size and number, and hatching success, along with temperature and phytoplankton biomass. The amplitude of the plastic responses was estimated with the Phenotypic Plasticity Index. This index was also computed for a published dataset of 84 copepod populations to look if there is a relationship between the amplitude of the phenotypic plasticity of adult size and seasonal change in temperature. The temperature annual range in Lake Alchichica was 3.2°C, whereas phytoplankton abundance varied 17-fold. A strong pattern of thermal plasticity in egg size and adult female size followed the inverse relationship with temperature commonly observed in temperate environments, although its adaptive value was not demonstrated. Egg number, relative reproductive effort and number of nauplii per female were clearly plastic to food availability, allowing organisms to increase their fitness. When comparing copepod species from different latitudes, we found that the magnitude of thermal plasticity of adult size is not related to the range of temperature variation; furthermore, thermal plasticity exists even in environments of limited temperature variation, where the response is more intense compared to temperate populations.
Hernández-Martínez, Osvaldo; Ciros-Pérez, Jorge
2018-01-01
According to the Climatic Variability Hypothesis [CVH], thermal plasticity should be wider in organisms from temperate environments, but is unlikely to occur in tropical latitudes where temperature fluctuations are narrow. In copepods, food availability has been suggested as the main driver of phenotypic variability in adult size if the range of temperature change is less than 14°C. Leptodiaptomus garciai is a calanoid copepod inhabiting Lake Alchichica, a monomictic, tropical lake in Mexico that experiences regular, narrow temperature fluctuations but wide changes in phytoplankton availability. We investigated whether the seasonal fluctuations of temperature and food produce phenotypic variation in the life-history traits of this tropical species. We sampled L. garciai throughout a year and measured female size, egg size and number, and hatching success, along with temperature and phytoplankton biomass. The amplitude of the plastic responses was estimated with the Phenotypic Plasticity Index. This index was also computed for a published dataset of 84 copepod populations to look if there is a relationship between the amplitude of the phenotypic plasticity of adult size and seasonal change in temperature. The temperature annual range in Lake Alchichica was 3.2°C, whereas phytoplankton abundance varied 17-fold. A strong pattern of thermal plasticity in egg size and adult female size followed the inverse relationship with temperature commonly observed in temperate environments, although its adaptive value was not demonstrated. Egg number, relative reproductive effort and number of nauplii per female were clearly plastic to food availability, allowing organisms to increase their fitness. When comparing copepod species from different latitudes, we found that the magnitude of thermal plasticity of adult size is not related to the range of temperature variation; furthermore, thermal plasticity exists even in environments of limited temperature variation, where the response is more intense compared to temperate populations. PMID:29708999
Ruthrauff, Daniel R.; Dekinga, Anne; Gill, Robert E.; van Gils, Jan A.; Piersma, Theunis
2015-01-01
At what phenotypic level do closely related subspecies that live in different environments differ with respect to food detection, ingestion, and processing? This question motivated an experimental study on rock sandpipers (Calidris ptilocnemis). The species' nonbreeding range spans 20 degrees of latitude, the extremes of which are inhabited by two subspecies: Calidris p. ptilocnemis that winters primarily in upper Cook Inlet, Alaska (61°N), and C. p. tschuktschorum that overlaps slightly with C. p. ptilocnemis but whose range extends much farther south (~40°N). In view of the strongly contrasting energetic demands of their distinct nonbreeding distributions, we conducted experiments to assess the behavioural, physiological, and sensory aspects of foraging, and we used the bivalve Macoma balthica for all trials. Ptilocnemis consumed a wider range of prey sizes, had higher maximum rates of energy intake, processed shell waste at higher maximum rates, and handled prey more quickly. Notably, however, the two subspecies did not differ in their abilities to find buried prey. The subspecies were similar in size and had equally sized gizzards, but the more northern ptilocnemis individuals were 10-14% heavier than their same-sex tschuktschorum counterparts. The higher body mass in ptilocnemis likely resulted from hypertrophy of digestive organs (e.g. intestine, liver) related to digestion and nutrient assimilation. Given the previously established equality of the two subspecies' metabolic capacities, we propose that the high-latitude nonbreeding range of ptilocnemis rock sandpipers is primarily facilitated by digestive (i.e. physiological) aspects of their foraging ecology rather than behavioural or sensory aspects.
NASA Astrophysics Data System (ADS)
Tang, Hong; Lin, Jian-Zhong
2013-01-01
An improved anomalous diffraction approximation (ADA) method is presented for calculating the extinction efficiency of spheroids firstly. In this approach, the extinction efficiency of spheroid particles can be calculated with good accuracy and high efficiency in a wider size range by combining the Latimer method and the ADA theory, and this method can present a more general expression for calculating the extinction efficiency of spheroid particles with various complex refractive indices and aspect ratios. Meanwhile, the visible spectral extinction with varied spheroid particle size distributions and complex refractive indices is surveyed. Furthermore, a selection principle about the spectral extinction data is developed based on PCA (principle component analysis) of first derivative spectral extinction. By calculating the contribution rate of first derivative spectral extinction, the spectral extinction with more significant features can be selected as the input data, and those with less features is removed from the inversion data. In addition, we propose an improved Tikhonov iteration method to retrieve the spheroid particle size distributions in the independent mode. Simulation experiments indicate that the spheroid particle size distributions obtained with the proposed method coincide fairly well with the given distributions, and this inversion method provides a simple, reliable and efficient method to retrieve the spheroid particle size distributions from the spectral extinction data.
Home range overlap as a driver of intelligence in primates.
Grueter, Cyril C
2015-04-01
Various socioecological factors have been suggested to influence cognitive capacity in primates, including challenges associated with foraging and dealing with the complexities of social life. Alexander [Alexander, 1989]. Evolution of the human psyche. In: Mellars P, Stringer C, editors. The human revolution: Behavioural and biological perspectives on the origins of modern humans. Princeton: Princeton University Press. p 455-513] proposed an integrative model for the evolution of human cognitive abilities and complex sociality that incorporates competition among coalitions of conspecifics (inter-group conflict) as a major selective pressure. However, one of the premises of this model, i.e., that when confronted with inter-group conflict selection should favor enhanced cognition, has remained empirically untested. Using a comparative approach on species data, I aimed to test the prediction that primate species (n = 104) that face greater inter-group conflict have higher cognitive abilities (indexed by endocranial volume). The degree of inter-group conflict/complexity was approximated via the variable home range overlap among groups. I found a significant relationship between home range overlap and endocranial volume, even after controlling for other predictor variables and covariates such as group size and body mass. I conclude that brain size evolution cannot be attributed exclusively to social factors such as group size, but likely reflects a variety of social and ecological determinants including inter-group conflict which poses cognitive demands on monitoring both the wider social milieu as well as spatial attributes of the habitat. © 2014 Wiley Periodicals, Inc.
Scaling tunable network model to reproduce the density-driven superlinear relation
NASA Astrophysics Data System (ADS)
Gao, Liang; Shan, Xiaoya; Qin, Yuhao; Yu, Senbin; Xu, Lida; Gao, Zi-You
2018-03-01
Previous works have shown the universality of allometric scaling under total and density values at the city level, but our understanding of the size effects of regions on the universality of allometric scaling remains inadequate. Here, we revisit the scaling relations between the gross domestic production (GDP) and the population based on the total and density values and first reveal that the allometric scaling under density values for different regions is universal. The scaling exponent β under the density value is in the range of (1.0, 2.0], which unexpectedly exceeds the range observed by Pan et al. [Nat. Commun. 4, 1961 (2013)]. For the wider range, we propose a network model based on a 2D lattice space with the spatial correlation factor α as a parameter. Numerical experiments prove that the generated scaling exponent β in our model is fully tunable by the spatial correlation factor α. Our model will furnish a general platform for extensive urban and regional studies.
Shigeta, Masaya; Watanabe, Takayuki
2016-01-01
A computational investigation using a unique model and a solution algorithm was conducted, changing only the saturation pressure of one material artificially during nanopowder formation in thermal plasma fabrication, to highlight the effects of the saturation pressure difference between a metal and silicon. The model can not only express any profile of particle size–composition distribution for a metal–silicide nanopowder even with widely ranging sizes from sub-nanometers to a few hundred nanometers, but it can also simulate the entire growth process involving binary homogeneous nucleation, binary heterogeneous co-condensation, and coagulation among nanoparticles with different compositions. Greater differences in saturation pressures cause a greater time lag for co-condensation of two material vapors during the collective growth of the metal–silicide nanopowder. The greater time lag for co-condensation results in a wider range of composition of the mature nanopowder. PMID:28344300
Investigation of the detection of shallow tunnels using electromagnetic and seismic waves
NASA Astrophysics Data System (ADS)
Counts, Tegan; Larson, Gregg; Gürbüz, Ali Cafer; McClellan, James H.; Scott, Waymond R., Jr.
2007-04-01
Multimodal detection of subsurface targets such as tunnels, pipes, reinforcement bars, and structures has been investigated using both ground-penetrating radar (GPR) and seismic sensors with signal processing techniques to enhance localization capabilities. Both systems have been tested in bi-static configurations but the GPR has been expanded to a multi-static configuration for improved performance. The use of two compatible sensors that sense different phenomena (GPR detects changes in electrical properties while the seismic system measures mechanical properties) increases the overall system's effectiveness in a wider range of soils and conditions. Two experimental scenarios have been investigated in a laboratory model with nearly homogeneous sand. Images formed from the raw data have been enhanced using beamforming inversion techniques and Hough Transform techniques to specifically address the detection of linear targets. The processed data clearly indicate the locations of the buried targets of various sizes at a range of depths.
Wu, Rongrong; Shen, Feiran; Hu, Fengxia; Wang, Jing; Bao, Lifu; Zhang, Lei; Liu, Yao; Zhao, Yingying; Liang, Feixiang; Zuo, Wenliang; Sun, Jirong; Shen, Baogen
2016-01-01
Magnetostructural coupling, which is the coincidence of crystallographic and magnetic transition, has obtained intense attention for its abundant magnetoresponse effects and promising technological applications, such as solid-state refrigeration, magnetic actuators and sensors. The hexagonal Ni2In-type compounds have attracted much attraction due to the strong magnetostructural coupling and the resulted giant negative thermal expansion and magnetocaloric effect. However, the as-prepared samples are quite brittle and naturally collapse into powders. Here, we report the effect of particle size on the magnetostructural coupling and magnetocaloric effect in the Ni2In-type Mn-Fe-Ni-Ge compound, which undergoes a large lattice change across the transformation from paramagnetic austenite to ferromagnetic martensite. The disappearance of martensitic transformation in a large amount of austenitic phase with reducing particle size, to our best knowledge, has not been reported up to now. The ratio can be as high as 40.6% when the MnNi0.8Fe0.2Ge bulk was broken into particles in the size range of 5~15 μm. Meanwhile, the remained magnetostructural transition gets wider and the magnetic hysteresis becomes smaller. As a result, the entropy change drops, but the effective cooling power RCeffe increases and attains to the maximum at particles in the range of 20~40 μm. These observations provide constructive information and highly benefit practical applications for this class of novel magnetoresponse materials. PMID:26883719
The efficacy of cognitive behavioral therapy for Chinese people: A meta-analysis.
Ng, Ting Kin; Wong, Daniel Fu Keung
2018-07-01
Over the past decade, cognitive behavioral therapy has been applied to an increasingly wider range of disorders and problems in Chinese societies. However, no meta-analysis has been conducted to synthesize the studies on cognitive behavioral therapy for Chinese clients. The purpose of this meta-analytic study was to examine the overall efficacy of cognitive behavioral therapy for Chinese people. A literature search was conducted using electronic databases, including Web of Science, PsycINFO and PubMed. Pooled mean effect sizes were calculated using the random-effects model. The literature search identified 55 studies with 6763 Chinese participants. The overall short-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Effect sizes were medium for anxiety, depression/well-being and caregiving stress and small for psychotic symptoms and addictive behaviors. The effects of cognitive behavioral therapy on process variables, dysfunctional thoughts and coping, were in the small range. The overall longer-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Moderator analyses showed that the short-term effect was stronger for culturally adapted cognitive behavioral therapy than for unadapted cognitive behavioral therapy. Type of primary outcome, type of control group, recruitment method, study design, the format of delivery and region were found to moderate the efficacy of cognitive behavioral therapy. The findings of this study provide evidence for the overall efficacy of cognitive behavioral therapy for Chinese people and the benefit of cultural adaptation of cognitive behavioral therapy to Chinese culture.
Mean effective size and refractive index of transparent atmospheric particulates
NASA Technical Reports Server (NTRS)
Fymat, A. L.
1975-01-01
It is demonstrated that the scattering ratio-principle originally restricted to exact forward and exact backward scattering, and to values of the size parameter and of the product (refractive index x size parameter) less than 0.8 has a much wider applicability. After relaxing these stringent conditions, it is also shown that this principle can be retained as the basis of an experimental technique for retrieving the mean effective size and refractive index of transparent atmospheric particulates.
Miklaszewski, Andrzej; Jurczyk, Mieczysława U; Kaczmarek, Mariusz; Paszel-Jaworska, Anna; Romaniuk, Aleksandra; Lipińska, Natalia; Żurawski, Jakub; Urbaniak, Paulina; Jurczyk, Mieczyslaw
2017-04-01
Novel in situ Metal Matrix Nanocomposite (MMNC) materials based on titanium and boron, revealed their new properties in the nanoscale range. In situ nanocomposites, obtained through mechanical alloying and traditional powder metallurgy compaction and sintering, show obvious differences to their microstructural analogue. A unique microstructure connected with good mechanical properties reliant on the processing conditions favour the nanoscale range of results of the Ti-TiB in situ MMNC example. The data summarised in this work, support and extend the knowledge boundaries of the nanoscale size effect that influence not only the mechanical properties but also the studies on the cell viability and cytocompatibility. Prepared in the same bulk, in situ MMNC, based on titanium and boron, could be considered as a possible candidate for dental implants and other medical applications. The observed relations and research conclusions are transferable to the in situ MMNC material group. Aside from all the discussed relations, the increasing share of these composites in the ever-growing material markets, heavily depends on the attractiveness and a possible wider application of these composites as well as their operational simplicity presented in this work. Copyright © 2016 Elsevier B.V. All rights reserved.
Pectin characterisation using size exclusion chromatography: A comparison of ELS and RI detection.
Muñoz-Almagro, Nerea; Rico-Rodriguez, Fabián; Villamiel, Mar; Montilla, Antonia
2018-06-30
A high-performance size-exclusion chromatography (HPSEC) method coupled to Evaporative Light Scattering (ELS) and Refractive Index (RI) detectors were evaluated and compared for the molecular mass (Mw) estimation of pectin in a wide range (0.342-805 kDa). Instrumental parameters of the ELSD were optimised by Response Surface Methodology (RSM) being 73 °C the evaporator temperature and 0.9 mL/min the air flow rate. The linear range for the ELSD concentration response was wider (10-2250 mg/L) and better (R 2 = 0.985) than RID (10-1500 mg/L; R 2 = 0.875). The limits of detection (LOD) and quantitation (LOQ) for all pullulans hardly changed in ELSD (LOD: 1.22-1.99 mg/L; LOQ: 4.07-6.63 mg/L); however, RID showed huge variations (LOD: 0.49-10.41 mg/L; LOQ: 1.64-34.70 mg/L), which increased with the Mw. In general, responses of both detectors were similar for the Mw estimation, although pectin characterisation with HPSEC-ELSD exhibited better results in the lowest Mw compounds. Copyright © 2018 Elsevier Ltd. All rights reserved.
Rutterford, Clare; Taljaard, Monica; Dixon, Stephanie; Copas, Andrew; Eldridge, Sandra
2015-06-01
To assess the quality of reporting and accuracy of a priori estimates used in sample size calculations for cluster randomized trials (CRTs). We reviewed 300 CRTs published between 2000 and 2008. The prevalence of reporting sample size elements from the 2004 CONSORT recommendations was evaluated and a priori estimates compared with those observed in the trial. Of the 300 trials, 166 (55%) reported a sample size calculation. Only 36 of 166 (22%) reported all recommended descriptive elements. Elements specific to CRTs were the worst reported: a measure of within-cluster correlation was specified in only 58 of 166 (35%). Only 18 of 166 articles (11%) reported both a priori and observed within-cluster correlation values. Except in two cases, observed within-cluster correlation values were either close to or less than a priori values. Even with the CONSORT extension for cluster randomization, the reporting of sample size elements specific to these trials remains below that necessary for transparent reporting. Journal editors and peer reviewers should implement stricter requirements for authors to follow CONSORT recommendations. Authors should report observed and a priori within-cluster correlation values to enable comparisons between these over a wider range of trials. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Dietary specialization is linked to reduced species durations in North American fossil canids
Casey, Corinna; Van Valkenburgh, Blaire
2018-01-01
How traits influence species persistence is a fundamental question in ecology, evolution and palaeontology. We test the relationship between dietary traits and both species duration and locality coverage over 40 million years in North American canids, a clade with considerable ecomorphological disparity and a dense fossil record. Because ecomorphological generalization—broad resource use—may enable species to withstand disturbance, we predicted that canids of average size and mesocarnivory would exhibit longer durations and wider distributions than specialized larger or smaller species. Second, because locality coverage might reflect dispersal ability and/or survivability in a range of habitats, we predicted that high coverage would correspond with longer durations. We find a nonlinear relationship between species duration and degree of carnivory: species at either end of the carnivory spectrum tend to have shorter durations than mesocarnivores. Locality coverage shows no relationship with size, diet or duration. To test whether generalization (medium size, mesocarnivory) corresponds to an adaptive optimum, we fit trait evolution models to previously generated canid phylogenies. Our analyses identify no single optimum in size or diet. Instead, the primary model of size evolution is a classic Cope's Rule increase over time, while dietary evolution does not conform to a single model. PMID:29765649
Ruthrauff, Daniel R.; Dekinga, Anne; Gill, Robert E.; van Gils, Jan A.; Piersma, Theunis
2015-01-01
At what phenotypic level do closely related subspecies that live in different environments differ with respect to food detection, ingestion and processing? This question motivated an experimental study on rock sandpipers (Calidris ptilocnemis). The species' nonbreeding range spans 20 deg of latitude, the extremes of which are inhabited by two subspecies: C. p. ptilocnemis that winters primarily in upper Cook Inlet, Alaska (61°N) and C. p. tschuktschorum that overlaps slightly with C. p. ptilocnemis but whose range extends much farther south (∼40°N). In view of the strongly contrasting energetic demands of their distinct nonbreeding distributions, we conducted experiments to assess the behavioral, physiological and sensory aspects of foraging and we used the bivalve Macoma balthica for all trials. C. p. ptilocnemis consumed a wider range of prey sizes, had higher maximum rates of energy intake, processed shell waste at higher maximum rates and handled prey more quickly. Notably, however, the two subspecies did not differ in their abilities to find buried prey. The subspecies were similar in size and had equally sized gizzards, but the more northern ptilocnemis individuals were 10–14% heavier than their same-sex tschuktschorum counterparts. The higher body mass in ptilocnemis probably resulted from hypertrophy of digestive organs (e.g. intestine, liver) related to digestion and nutrient assimilation. Given the previously established equality of the metabolic capacities of the two subspecies, we propose that the high-latitude nonbreeding range of ptilocnemis rock sandpipers is primarily facilitated by digestive (i.e. physiological) aspects of their foraging ecology rather than behavioral or sensory aspects.
Principles of gas phase processing of ceramics during combustion
NASA Technical Reports Server (NTRS)
Zachariah, Michael R.
1993-01-01
In recent years, ceramic materials have found applications in an increasingly wider range of industrial processes, where their unique mechanical, electrical and optical properties are exploited. Ceramics are especially useful for applications in high temperature, corrosive environments, which impose particularly stringent requirements on mechanical reliability. One approach to provide such materials is the manufacture of submicron (and more recently nanometer scale) particles, which may subsequently be sintered to produce a material with extremely high mechanical integrity. However, high quality ceramic materials can only be obtained if particles of known size, polydispersity, shape and chemical purity can be produced consistently, under well controlled conditions. These requirements are the fundamental driving force for the renewed interest in studying particle formation and growth of such materials.
Fundamental Fractal Antenna Design Process
NASA Astrophysics Data System (ADS)
Zhu, L. P.; Kim, T. C.; Kakas, G. D.
2017-12-01
Antenna designers are always looking to come up with new ideas to push the envelope for new antennas, using a smaller volume while striving for higher bandwidth, wider bandwidth, and antenna gain. One proposed method of increasing bandwidth or shrinking antenna size is via the use of fractal geometry, which gives rise to fractal antennas. Fractals are those fun shapes that if one zooms in or zoom out, the structure is always the same. Design a new type of antenna based on fractal antenna design by utilize the Design of Experiment (DOE) will be shown in fractal antenna design process. Investigate conformal fractal antenna design for patterns, dimensions, and size, of the antenna but maintaining or improving the antenna performance. Research shows an antenna designer how to create basic requirements of the fractal antenna through a step by step process, and provides how to optimize the antenna design with the model prediction, lab measurement, and actual results from the compact range measurement on the antenna patterns.
NASA Astrophysics Data System (ADS)
Chen, Xiaolong; Honda, Hiroshi; Kuroda, Seiji; Araki, Hiroshi; Murakami, Hideyuki; Watanabe, Makoto; Sakka, Yoshio
2016-12-01
Effects of the ceramic powder size used for suspension as well as several processing parameters in suspension plasma spraying of YSZ were investigated experimentally, aiming to fabricate highly segmented microstructures for thermal barrier coating (TBC) applications. Particle image velocimetry (PIV) was used to observe the atomization process and the velocity distribution of atomized droplets and ceramic particles travelling toward the substrates. The tested parameters included the secondary plasma gas (He versus H2), suspension injection flow rate, and substrate surface roughness. Results indicated that a plasma jet with a relatively higher content of He or H2 as the secondary plasma gas was critical to produce highly segmented YSZ TBCs with a crack density up to 12 cracks/mm. The optimized suspension flow rate played an important role to realize coatings with a reduced porosity level and improved adhesion. An increased powder size and higher operation power level were beneficial for the formation of highly segmented coatings onto substrates with a wider range of surface roughness.
Cooper, Keith M
2012-08-01
In the UK, Government policy requires marine aggregate extraction companies to leave the seabed in a similar physical condition after the cessation of dredging. This measure is intended to promote recovery, and the return of a similar faunal community to that which existed before dredging. Whilst the policy is sensible, and in line with the principles of sustainable development, the use of the word 'similar' is open to interpretation. There is, therefore, a need to set quantifiable limits for acceptable change in sediment composition. Using a case study site, it is shown how such limits could be defined by the range of sediment particle size composition naturally found in association with the faunal assemblages in the wider region. Whilst the approach offers a number of advantages over the present system, further testing would be required before it could be recommended for use in the regulatory context. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
Interfacial mixing in high energy-density matter with a multiphysics kinetic model
NASA Astrophysics Data System (ADS)
Haack, Jeff; Hauck, Cory; Murillo, Michael
2017-10-01
We have extended a recently-developed multispecies, multitemperature BGK model to include multiphysics capability that allows modeling of a wider range of plasma conditions. In particular, we have extended the model to describe one spatial dimension, and included a multispecies atomic ionization model, accurate collision physics across coupling regimes, self-consistent electric fields, and degeneracy in the electronic screening. We apply the new model to a warm dense matter scenario in which the ablator-fuel interface of an inertial confinement fusion target is heated, similar to a recent molecular dynamics study, but for larger length and time scales and for much higher temperatures. From our numerical results we are able to explore a variety of phenomena, including hydrogen jetting, kinetic effects (non-Maxwellian and anisotropic distributions), plasma physics (size, persistence and role of electric fields) and transport (relative sizes of Fickean diffision, electrodiffusion and barodiffusion). As compared with the recent molecular dynamics work the kinetic model greatly extends the accessible physical domains we are able to model.
Tan, Eugene S J; Yap, Jonathan; Xu, Chang Fen; Feng, Liang; Nyunt, Shwe Zin; Santhanakrishnan, Rajalakshmi; Chan, Michelle M Y; Seow, Swee Chong; Ching, Chi Keong; Yeo, Khung Keong; Richards, A Mark; Ng, Tze Pin; Lim, Toon Wei; Lam, Carolyn S P
2016-07-01
Existing electrocardiographic (ECG) reference values were derived in middle-aged Caucasian adults. We aimed to assess the association of age, sex, body size and ethnicity on ECG parameters in a multi-ethnic Asian population. Resting 12-lead ECG and anthropometric measurements were performed in a community-based cohort of 3777 older Asians (age 64.7±9.1 years, 1467 men, 88.8% Chinese, 7.7% Malay, 3.5% Indian, body mass index [BMI] 24.0±3.9kg/m(2)). Men had longer PR interval, wider QRS, shorter QTc interval and taller SV3. In both sexes, older age was associated with longer PR interval, wider QRS, larger R aVL and more leftward QRS axis, while higher BMI was associated with longer PR interval, wider QRS, larger RaVL and more negative QRS axis. There were significant inter-ethnic differences in QRS duration among men, as well as in PR and QTc intervals among women (all adjusted p<0.05). Findings were similar in a healthy subset of 1158 adults (age 61.2±9.1 years, 365 men) without cardiovascular risk factors. These first community-based ECG data in multi-ethnic older Asians highlight the independent effects of age, sex, body size and ethnicity on ECG parameters. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
McClain, A D; van den Bos, W; Matheson, D; Desai, M; McClure, S M; Robinson, T N
2014-05-01
The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate's rim width and coloring influence perceptual bias to affect perceived food portion size. Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multilevel logistic regression examined the effects of rim width and coloring on perceived food portion size. Experiment 1: participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared with plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared with plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes.
NASA Astrophysics Data System (ADS)
Riva'i, Imam; Oktavia Wulandari, Ika; Sulistyarti, Hermin; Sabarudin, Akhmad
2018-01-01
In this study, the synthesis of Fe3O4 nanoparticles was done with surface modification using PVA with coprecipitation-ultrasonication method. Time variations and PVA concentrations were added to determine the effect on crystallite size and lattice parameters on the synthesis of Fe3O4-PVA nanoparticles. Fe3O4 characterization was done using X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) instruments. FTIR was employed to determine PVA coating on the surface of Fe3O4 nanoparticles. The crystallite size and lattice parameters were analyzed using XRD. From the FTIR data, it is known that the interaction between PVA and Fe3O4 nanoparticles is characterized by Fe-O-C group at 1100 cm-1 region which is characteristic of Fe3O4-PVA nanoparticles, C-H groups of PVA in the range of 2950 cm-1 wave number, C-C of PVA regions of wave number 1405 cm-1, Fe3O4 and Fe3O4-PVA samples are in the range of 565 cm-1. In addition, the variation of ultrasonication time and the addition of PVA concentration have an effect on the crystallite size change and the lattice parameter observed from the XRD data. The use of ultrasonication time will affect the size of the crystallite become smaller and the grating lattice parameters obtained are wider. The effect of addition of PVA showed that higher concentration of PVA resulted in smaller crystallite size and larger lattice parameters. These results indicated that ultrasonication time and addition of PVA concentration greatly affect the characteristics of nanoparticles.
Greenhill, Simon J.; Hua, Xia; Welsh, Caela F.; Schneemann, Hilde; Bromham, Lindell
2018-01-01
What role does speaker population size play in shaping rates of language evolution? There has been little consensus on the expected relationship between rates and patterns of language change and speaker population size, with some predicting faster rates of change in smaller populations, and others expecting greater change in larger populations. The growth of comparative databases has allowed population size effects to be investigated across a wide range of language groups, with mixed results. One recent study of a group of Polynesian languages revealed greater rates of word gain in larger populations and greater rates of word loss in smaller populations. However, that test was restricted to 20 closely related languages from small Oceanic islands. Here, we test if this pattern is a general feature of language evolution across a larger and more diverse sample of languages from both continental and island populations. We analyzed comparative language data for 153 pairs of closely-related sister languages from three of the world's largest language families: Austronesian, Indo-European, and Niger-Congo. We find some evidence that rates of word loss are significantly greater in smaller languages for the Indo-European comparisons, but we find no significant patterns in the other two language families. These results suggest either that the influence of population size on rates and patterns of language evolution is not universal, or that it is sufficiently weak that it may be overwhelmed by other influences in some cases. Further investigation, for a greater number of language comparisons and a wider range of language features, may determine which of these explanations holds true. PMID:29755387
The pasty propellant rocket engine development
NASA Astrophysics Data System (ADS)
Kukushkin, V. I.; Ivanchenko, A. N.
1993-06-01
The paper describes a newly developed pasty propellant rocket engine (PPRE) and the combustion process and presents results of performance tests. It is shown that, compared with liquid propellant rocket engines, the PPREs can regulate the thrust level within a wider range, are safer ecologically, and have better weight characteristics. Compared with solid propellant rocket engines, the PPREs may be produced with lower costs and more safely, are able to regulate thrust performance within a wider range, and are able to offer a greater scope for the variation of the formulation components and propellant characteristics. Diagrams of the PPRE are included.
Winter Precipitation Efficiency of Mountain Ranges in the Colorado Rockies Under Climate Change
NASA Astrophysics Data System (ADS)
Eidhammer, Trude; Grubišić, Vanda; Rasmussen, Roy; Ikdea, Kyoko
2018-03-01
Orographic precipitation depends on the environmental conditions and the barrier shape. In this study we examine the sensitivity of the precipitation efficiency (i.e., drying ratio (DR)), defined as the ratio of precipitation to incoming water flux, to mountain shape, temperature, stability, and horizontal velocity of the incoming air mass. Furthermore, we explore how the DR of Colorado mountain ranges might change under warmer and moister conditions in the future. For given environmental conditions, we find the DR to be primarily dependent on the upwind slope for mountain ranges wider than about 70 km and on both the slope and width for narrower ranges. Temperature is found to exert an influence on the DR for all Colorado mountain ranges, with DR decreasing with increasing temperature, under both the current and future climate conditions. The decrease of DR with temperature under warmer climate was found to be stronger for wider mountains than the narrower ones. We attribute this asymmetry to the sensitivity of DR to reduced horizontal velocity under warmer conditions. Specifically, while DR for wider mountains shows no sensitivity to changes in horizontal velocity, the DR for narrow ranges increases as the horizontal velocity decreases and more time is provided for precipitation to form. Thus, for narrower ranges, the horizontal velocity appears to offset the temperature effect slightly. The percentagewise decrease of DR for all examined mountain ranges is about 4%K-1. In comparison, the increase in precipitation is about 6%K-1 while the vapor flux increase is about 9%K-1.
Foster, E; Matthews, J N S; Lloyd, J; Marshall, L; Mathers, J C; Nelson, M; Barton, K L; Wrieden, W L; Cornelissen, P; Harris, J; Adamson, A J
2008-01-01
A number of methods have been developed to assist subjects in providing an estimate of portion size but their application in improving portion size estimation by children has not been investigated systematically. The aim was to develop portion size assessment tools for use with children and to assess the accuracy of children's estimates of portion size using the tools. The tools were food photographs, food models and an interactive portion size assessment system (IPSAS). Children (n 201), aged 4-16 years, were supplied with known quantities of food to eat, in school. Food leftovers were weighed. Children estimated the amount of each food using each tool, 24 h after consuming the food. The age-specific portion sizes represented were based on portion sizes consumed by children in a national survey. Significant differences were found between the accuracy of estimates using the three tools. Children of all ages performed well using the IPSAS and food photographs. The accuracy and precision of estimates made using the food models were poor. For all tools, estimates of the amount of food served were more accurate than estimates of the amount consumed. Issues relating to reporting of foods left over which impact on estimates of the amounts of foods actually consumed require further study. The IPSAS has shown potential for assessment of dietary intake with children. Before practical application in assessment of dietary intake of children the tool would need to be expanded to cover a wider range of foods and to be validated in a 'real-life' situation.
Recent improvements in hydrometeor sampling using airborne holography
NASA Astrophysics Data System (ADS)
Stith, J. L.; Bansemer, A.; Glienke, S.; Shaw, R. A.; Aquino, J.; Fugal, J. P.
2017-12-01
Airborne digital holography provides a new technique to study the sizes, shapes and locations of hydrometeors. Airborne holographic cameras are able to capture more optical information than traditional airborne hydrometeor instruments, which allows for more detailed information, such as the location and shape of individual hydrometeors over a relatively wide range of sizes. These cameras can be housed in an anti-shattering probe arm configuration, which minimizes the effects of probe tip shattering. Holographic imagery, with its three dimensional view of hydrometeor spacing, is also well suited to detecting shattering events when present. A major problem with digital holographic techniques has been the amount of machine time and human analysis involved in analyzing holographic data. Here, we present some recent examples showing how holographic analysis can improve our measurements of liquid and ice particles and we describe a format we have developed for routine archiving of Holographic data, so that processed results can be utilized more routinely by a wider group of investigators. We present a side-by-side comparison of the imagery obtained from holographic reconstruction of ice particles from a holographic camera (HOLODEC) with imagery from a 3VCPI instrument, which utilizes a tube-based sampling geometry. Both instruments were carried on the NSF/NCAR GV aircraft. In a second application of holographic imaging, we compare measurements of cloud droplets from a Cloud Droplet Probe (CDP) with simultaneous measurements from HOLODEC. In some cloud regions the CDP data exhibits a bimodal size distribution, while the more local data from HOLODEC suggests that two mono-modal size distributions are present in the cloud and that the bimodality observed in the CDP is due to the averaging length. Thus, the holographic techniques have the potential to improve our understanding of the warm rain process in future airborne field campaigns. The development of this instrument has been a university and national lab collaboration. Progress in automating the processing techniques has now reached a stage where processed data can be made readily available, so that holographic data from a field campaign can be utilized by a wider group of investigators.
MacLaren, Julie-Ann
2018-01-01
Supervised practice as a mentor is currently an integral component of nurse mentor education. However, workplace education literature tends to focus on dyadic mentor-student relationships rather than developmental relationships between colleagues. This paper explores the supportive relationships of nurses undertaking a mentorship qualification, using the novel technique of constellation development to determine the nature of workplace support for this group. Semi-structured interviews were conducted with three recently qualified nurse mentors. All participants developed a mentorship constellation identifying colleagues significant to their own learning in practice. These significant others were also interviewed alongside practice education, and nurse education leads. Constellations were analysed in relation to network size, breadth, strength of relationships, and attributes of individuals. Findings suggest that dyadic forms of supervisory mentorship may not offer the range of skills and attributes that developing mentors require. Redundancy of mentorship attributes within the constellation (overlapping attributes between members) may counteract problems caused when one mentor attempts to fulfil all mentorship roles. Wider nursing teams are well placed to provide the support and supervision required by mentors in training. Where wider and stronger networks were not available to mentorship students, mentorship learning was at risk. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
True resolution enhancement for optical spectroscopy
NASA Astrophysics Data System (ADS)
Cooper, Justin T.; Oleske, Jeffrey B.
2018-02-01
Resolving spectrally adjacent peaks is important for techniques, such as tracking small shifts in Raman or fluorescence spectra, quantifying pharmaceutical polymorph ratios, or molecular orientation studies. Thus, suitable spectral resolution is a vital consideration when designing most spectroscopic systems. Most parameters that influence spectral resolution are fixed for a given system (spectrometer length, grating groove density, excitation source, CCD pixel size, etc.). Inflexible systems are non-problematic if the spectrometer is dedicated for a single purpose; however, these specifications cannot be optimized for different applications with wider range resolution requirements. Data processing techniques, including peak fitting, partial least squares, or principal component analysis, are typically used to achieve sub-optical resolution information. These techniques can be plagued by spectral artifacts introduced by post-processing as well as the subjective implementation of statistical parameters. TruRes™, from Andor Technology, uses an innovative optical means to greatly improve and expand the range of spectral resolutions accessible on a single setup. True spectral resolution enhancement of >30% is achieved without mathematical spectral alteration, dataprocessing, or spectrometer component changes. Discreet characteristic spectral lines from Laser-Induced Breakdown Spectroscopy (LIBS) and atomic calibration sources are now fully resolved from spectrally-adjacent peaks under otherwise identical configuration. TruRes™ has added advantage of increasing the spectral resolution without sacrificing bandpass. Using TruRes™ the Kymera 328i resolution can approach that of a 500 mm focal spectrometer. Furthermore, the bandpass of a 500 mm spectrograph with would be 50% narrower than the Kymera 328i with all other spectrometer components constant. However, the Kymera 328i with TruRes™ is able to preserve a 50% wider bandpass.
Mammalian brain development and our grandmothering life history.
Hawkes, Kristen; Finlay, Barbara L
2018-05-02
Among mammals, including humans, adult brain size and the relative size of brain components depend precisely on the duration of a highly regular process of neural development. Much wider variation is seen in rates of body growth and the state of neural maturation at life history events like birth and weaning. Large brains result from slow maturation, which in humans is accompanied by weaning early with respect to both neural maturation and longevity. The grandmother hypothesis proposes this distinctive combination of life history features evolved as ancestral populations began to depend on foods that just weaned juveniles couldn't handle. Here we trace possible reciprocal connections between brain development and life history, highlighting the resulting extended neural plasticity in a wider cognitive ecology of allomaternal care that distinguishes human ontogeny with consequences for other peculiarities of our lineage. Copyright © 2018 Elsevier Inc. All rights reserved.
Smoke and mirrors: Testing the scope of chimpanzees’ appearance-reality understanding
Lurz, Robert; Russell, Jamie L.; Hopkins, William D.
2016-01-01
The ability to make appearance-reality (AR) discriminations is an important higher-order cognitive adaptation in humans but is still poorly understood in our closest primate relatives. Previous research showed that chimpanzees are capable of AR discrimination when choosing between food items that appear, due to the effects of distorting lenses, to be smaller or larger than they actually are (Krachun, Call & Tomasello, 2009). In the current study, we investigated the scope and flexibility of chimpanzees’ AR discrimination abilities by presenting them with a wider range of illusory stimuli. In addition to using lenses to change the apparent size of food items (Experiment 1), we used a mirror to change the apparent number of items (Experiment 2), and tinted filters to change their apparent color (Experiment 3). In all three experiments, some chimpanzees were able to maximize their food rewards by making a choice based on the real properties of the stimuli in contrast to their manifest apparent properties. These results replicate the earlier findings for size illusions and extend them to additional situations involving illusory number and color. Control tests, together with findings from previous studies, ruled out lower-level explanations for the chimpanzees’ performance. The findings thus support the hypothesis that chimpanzees are capable of making AR discriminations with a range of illusory stimuli. PMID:26848736
Thomas, Michael; Corry, Ben
2016-01-01
Membranes made from nanomaterials such as nanotubes and graphene have been suggested to have a range of applications in water filtration and desalination, but determining their suitability for these purposes requires an accurate assessment of the properties of these novel materials. In this study, we use molecular dynamics simulations to determine the permeability and salt rejection capabilities for membranes incorporating carbon nanotubes (CNTs) at a range of pore sizes, pressures and concentrations. We include the influence of osmotic gradients and concentration build up and simulate at realistic pressures to improve the reliability of estimated membrane transport properties. We find that salt rejection is highly dependent on the applied hydrostatic pressure, meaning high rejection can be achieved with wider tubes than previously thought; while membrane permeability depends on salt concentration. The ideal size of the CNTs for desalination applications yielding high permeability and high salt rejection is found to be around 1.1 nm diameter. While there are limited energy gains to be achieved in using ultra-permeable CNT membranes in desalination by reverse osmosis, such membranes may allow for smaller plants to be built as is required when size or weight must be minimized. There are diminishing returns in further increasing membrane permeability, so efforts should focus on the fabrication of membranes containing narrow or functionalized CNTs that yield the desired rejection or selection properties rather than trying to optimize pore densities. PMID:26712639
Big and beautiful? Evidence of racial differences in the perceived attractiveness of obese females.
Ali, Mir M; Rizzo, John A; Heiland, Frank W
2013-06-01
This paper investigates the relationships between body weight, race, and attractiveness in appearance and personality among adolescents. We study a sample of 5947 (non-Hispanic) white and black girls age 12 to 18 who were interviewed by a group of 338 interviewers. We find that overweight and obese white female adolescents are, respectively, 23% and 40% less likely, on average, to be perceived as physically attractive compared to normal-weight white girls. The physical appearance penalties are significantly smaller for overweight and obese black girls compared to white girls. These findings suggest that being overweight or obese is costly due to its negative impact on inner and outer perceived beauty, providing an explanation for the observed stigmatization of overweight and obesity among women in labor and relationship markets. The smaller beauty penalties for black girls above the normal-weight range suggest that the range of body sizes considered attractive may be wider for black females. Published by Elsevier Ltd.
Properties of AGN coronae in the NuSTAR era - II. Hybrid plasma
NASA Astrophysics Data System (ADS)
Fabian, A. C.; Lohfink, A.; Belmont, R.; Malzac, J.; Coppi, P.
2017-05-01
The corona, a hot cloud of electrons close to the centre of the accretion disc, produces the hard X-ray power-law continuum commonly seen in luminous active galactic nuclei. The continuum has a high-energy turnover, typically in the range of one to several 100 keV and is suggestive of Comptonization by thermal electrons. We are studying hard X-ray spectra of AGN obtained with NuSTAR after correction for X-ray reflection and under the assumption that coronae are compact, being only a few gravitational radii in size as indicated by reflection and reverberation modelling. Compact coronae raise the possibility that the temperature is limited and indeed controlled by electron-positron pair production, as explored earlier (Paper I). Here, we examine hybrid plasmas in which a mixture of thermal and non-thermal particles is present. Pair production from the non-thermal component reduces the temperature leading to a wider temperature range more consistent with observations.
NASA Technical Reports Server (NTRS)
Hapke, Bruce; DiMucci, Dominick; Nelson, Robert; Smythe, William
1996-01-01
Two different mechanisms, shadow-hiding and coherent backscatter, can cause a hot spot, or opposition effect, in the bidirectional reflectance of vegetation and soils. Because the two mechanisms sample different properties, it is important to know which one is primarily responsible in a given medium. This question can be answered by measuring the bidirectional reflectance in circularly polarized light. If the results of the limited experiments reported here can be extrapolated to a wider range of materials, it appears that the primary cause of the hot spot in most vegetation canopies and in moist, clumpy soils is shadow-hiding. However, in vegetation with large numbers of wavelength-sized structures, such as mosses, and in dry, fine-grained soils, the hot spot is dominated by coherent backscatter.
The absorption Ångström exponent of black carbon: from numerical aspects
NASA Astrophysics Data System (ADS)
Liu, Chao; Eddy Chung, Chul; Yin, Yan; Schnaiter, Martin
2018-05-01
The absorption Ångström exponent (AAE) is an important aerosol optical parameter used for aerosol characterization and apportionment studies. The AAE of black carbon (BC) particles is widely accepted to be 1.0, although observational estimates give quite a wide range of 0.6-1.3. With considerable uncertainties related to observations, a numerical study is a powerful method, if not the only one, to provide a better and more accurate understanding on BC AAE. This study calculates BC AAE using realistic particle geometries based on fractal aggregate and an accurate numerical optical model (namely the multiple-sphere T-matrix method), and considers bulk properties of an ensemble of BC particles following lognormal size distributions. At odds with the expectations, BC AAE is not 1.0, even when BC is assumed to have small sizes and a wavelength-independent refractive index. With a wavelength-independent refractive index, the AAE of fresh BC is approximately 1.05 and relatively insensitive to particle size. For BC with geometric mean diameters larger than 0.12 µm, BC AAE becomes smaller when BC particles are aged (compact structures or coated by other non-absorptive materials). For coated BC, we prescribe the coating fraction variation based on a laboratory study, where smaller BC cores are shown to develop larger coating fractions than those of bigger BC cores. For both compact and coated BC, the AAE is highly sensitive to particle size distribution, ranging from approximately 0.8 to even over 1.4 with wavelength-independent refractive index. When the refractive index is allowed to vary with wavelength, a feature with observational backing, the BC AAE may show an even wider range. For different BC morphologies, we derive simple empirical equations on BC AAE based on our numerical results, which can serve as a guide for the response of BC AAE to BC size and refractive index. Due to its complex influences, the effects of BC geometry is better to be discussed at certain BC properties, i.e., known size and refractive index.
McClain, Arianna; van den Bos, Wouter; Matheson, Donna; Desai, Manisha; McClure, Samuel M.; Robinson, Thomas N.
2013-01-01
OBJECTIVE The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate’s rim width and coloring influence perceptual bias to affect perceived food portion size. DESIGN AND METHODS Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multi-level logistic regression examined the effects of rim width and coloring on perceived food portion size. RESULTS Experiment 1: Participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared to plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: Participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared to plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. CONCLUSION The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes. PMID:24005858
NASA Astrophysics Data System (ADS)
Wittek, Peter; Calderaro, Luca
2015-12-01
We extended a parallel and distributed implementation of the Trotter-Suzuki algorithm for simulating quantum systems to study a wider range of physical problems and to make the library easier to use. The new release allows periodic boundary conditions, many-body simulations of non-interacting particles, arbitrary stationary potential functions, and imaginary time evolution to approximate the ground state energy. The new release is more resilient to the computational environment: a wider range of compiler chains and more platforms are supported. To ease development, we provide a more extensive command-line interface, an application programming interface, and wrappers from high-level languages.
Efficiency of planetesimal ablation in giant planetary envelopes
NASA Astrophysics Data System (ADS)
Pinhas, Arazi; Madhusudhan, Nikku; Clarke, Cathie
2016-12-01
Observations of exoplanetary spectra are leading to unprecedented constraints on their atmospheric elemental abundances, particularly O/H, C/H, and C/O ratios. Recent studies suggest that elemental ratios could provide important constraints on formation and migration mechanisms of giant exoplanets. A fundamental assumption in such studies is that the chemical composition of the planetary envelope represents the sum-total of compositions of the accreted gas and solids during the formation history of the planet. We investigate the efficiency with which accreted planetesimals ablate in a giant planetary envelope thereby contributing to its composition rather than sinking to the core. From considerations of aerodynamic drag causing `frictional ablation' and the envelope temperature structure causing `thermal ablation', we compute mass ablations for impacting planetesimals of radii 30 m to 1 km for different compositions (ice to iron) and a wide range of velocities and impact angles, assuming spherical symmetry. Icy impactors are fully ablated in the outer envelope for a wide range of parameters. Even for Fe impactors substantial ablation occurs in the envelope for a wide range of sizes and velocities. For example, iron impactors of sizes below ˜0.5 km and velocities above ˜30 km s-1 are found to ablate by ˜60-80 per cent within the outer envelope at pressures below 103 bar due to frictional ablation alone. For deeper pressures (˜107 bar), substantial ablation happens over a wider range of parameters. Therefore, our exploratory study suggests that atmospheric abundances of volatile elements in giant planets reflect their accretion history during formation.
Nakagawa, Fumiyo; van Sighem, Ard; Thiebaut, Rodolphe; Smith, Colette; Ratmann, Oliver; Cambiano, Valentina; Albert, Jan; Amato-Gauci, Andrew; Bezemer, Daniela; Campbell, Colin; Commenges, Daniel; Donoghoe, Martin; Ford, Deborah; Kouyos, Roger; Lodwick, Rebecca; Lundgren, Jens; Pantazis, Nikos; Pharris, Anastasia; Quinten, Chantal; Thorne, Claire; Touloumi, Giota; Delpech, Valerie; Phillips, Andrew
2016-03-01
It is important not only to collect epidemiologic data on HIV but to also fully utilize such information to understand the epidemic over time and to help inform and monitor the impact of policies and interventions. We describe and apply a novel method to estimate the size and characteristics of HIV-positive populations. The method was applied to data on men who have sex with men living in the UK and to a pseudo dataset to assess performance for different data availability. The individual-based simulation model was calibrated using an approximate Bayesian computation-based approach. In 2013, 48,310 (90% plausibility range: 39,900-45,560) men who have sex with men were estimated to be living with HIV in the UK, of whom 10,400 (6,160-17,350) were undiagnosed. There were an estimated 3,210 (1,730-5,350) infections per year on average between 2010 and 2013. Sixty-two percent of the total HIV-positive population are thought to have viral load <500 copies/ml. In the pseudo-epidemic example, HIV estimates have narrower plausibility ranges and are closer to the true number, the greater the data availability to calibrate the model. We demonstrate that our method can be applied to settings with less data, however plausibility ranges for estimates will be wider to reflect greater uncertainty of the data used to fit the model.
The role of foraging behaviour in the sexual segregation of the African elephant.
Shannon, Graeme; Page, Bruce R; Duffy, Kevin J; Slotow, Rob
2006-11-01
Elephants (Loxodonta africana) exhibit pronounced sexual dimorphism, and in this study we test the prediction that the differences in body size and sociality are significant enough to drive divergent foraging strategies and ultimately sexual segregation. Body size influences the foraging behaviour of herbivores through the differential scaling coefficients of metabolism and gut size, with larger bodied individuals being able to tolerate greater quantities of low-quality, fibrous vegetation, whilst having lower mass-specific energy requirements. We test two distinct theories: the scramble competition hypothesis (SCH) and the forage selection hypothesis (FSH). Comprehensive behavioural data were collected from the Pongola Game Reserve and the Phinda Private Game Reserve in South Africa over a 2.5-year period. The data were analysed using sex as the independent variable. Adult females targeted a wider range of species, adopted a more selective foraging approach and exhibited greater bite rates as predicted by the body size hypothesis and the increased demands of reproductive investment (lactation and pregnancy). Males had longer feeding bouts, displayed significantly more destructive behaviour (31% of observations, 11% for females) and ingested greater quantities of forage during each feeding bout. The independent ranging behaviour of adult males enables them to have longer foraging bouts as they experience fewer social constraints than females. The SCH was rejected as a cause of sexual segregation due to the relative abundance of low quality forage, and the fact that feeding heights were similar for both males and females. However, we conclude that the differences in the foraging strategies of the sexes are sufficient to cause spatial segregation as postulated by the FSH. Sexual dimorphism and the associated behavioural differences have important implications for the management and conservation of elephant and other dimorphic species, with the sexes effectively acting as distinct "ecological species".
Cundy, A B; Bardos, R P; Puschenreiter, M; Mench, M; Bert, V; Friesl-Hanl, W; Müller, I; Li, X N; Weyens, N; Witters, N; Vangronsveld, J
2016-12-15
Gentle remediation options (GROs) are risk management strategies or technologies involving plant (phyto-), fungi (myco-), and/or bacteria-based methods that result in a net gain (or at least no gross reduction) in soil function as well as effective risk management. GRO strategies can be customised along contaminant linkages, and can generate a range of wider economic, environmental and societal benefits in contaminated land management (and in brownfields management more widely). The application of GROs as practical on-site remedial solutions is still limited however, particularly in Europe and at trace element (typically metal and metalloid) contaminated sites. This paper discusses challenges to the practical adoption of GROs in contaminated land management, and outlines the decision support tools and best practice guidance developed in the European Commission FP7-funded GREENLAND project aimed at overcoming these challenges. The GREENLAND guidance promotes a refocus from phytoremediation to wider GROs- or phyto-management based approaches which place realisation of wider benefits at the core of site design, and where gentle remediation technologies can be applied as part of integrated, mixed, site risk management solutions or as part of "holding strategies" for vacant sites. The combination of GROs with renewables, both in terms of biomass generation but also with green technologies such as wind and solar power, can provide a range of economic and other benefits and can potentially support the return of low-level contaminated sites to productive usage, while combining GROs with urban design and landscape architecture, and integrating GRO strategies with sustainable urban drainage systems and community gardens/parkland (particularly for health and leisure benefits), has large potential for triggering GRO application and in realising wider benefits in urban and suburban systems. Quantifying these wider benefits and value (above standard economic returns) will be important in leveraging funding for GRO application and soft site end-use more widely at vacant or underutilized sites. Copyright © 2016 Elsevier Ltd. All rights reserved.
Overload characteristics of paper-polypropylene-paper cable
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ernst, A.
1990-09-01
The short-time rating of PPP pipe-type cable may be lower than the equivalent paper cable sized to carry the same normal load. The ratings depend on the relative conductor sizes and the maximum allowable conductor temperatures of the insulation. The insulation thermal resistivity may be a significant parameter for overload times of approximately one hour and should be verified for PPP insulation. The thermal capacitance temperature characteristic of PPP insulation is not known. However, the overload ratings are not very sensitive to this parameter. Overload ratings are given for maximum conductor temperatures from 105 C to 130 C. Use ofmore » ratings based on temperatures greater than 105 C would require testing to determine the extent of degradation of the insulation at these higher temperatures. PPP-insulated cable will be thermally stable over a wider range of operating conditions (voltage and current) compared with paper-insulated cable. The short-circuit ratings of PPP- and paper-insulated cable systems and the positive/negative and zero sequence impedances are compared. 21 refs., 22 figs., 5 tabs.« less
On the correlation of absorption cross-section with plasmonic color generation.
Rezaei, Soroosh Daqiqeh; Ho, Jinfa; Ng, Ray Jia Hong; Ramakrishna, Seeram; Yang, Joel K W
2017-10-30
Through numerical simulations, we investigate the correlation between the absorption cross-section and the color saturation of plasmonic nanostructures of varying density. Understanding this correlation, enables the prediction of an optimal nanostructure separation, or combinations of different nanostructure sizes for plasmonic color printing applications. Here, we use metal-insulator-metal (MIM) aluminum nanostructures that support gap-plasmons. Large absorption cross-sections were observed that exceed twelve times the physical cross-section of the nanostructure disks. We derive a set of equations to determine the optimal separation for a periodic array using the absorption cross-section of an individual structure to realize saturated colors. Using the optimum pitch and enabled by the large absorption cross-sections of our structures, we employ color mixing strategies to realize a wider color gamut. The simulated color gamut exceeds the sRGB gamut for some colors, and includes dark tones. Color mixing using structures with large absorption cross-sections is a practical approach to generate a broad range of colors, in comparison to fabricating structures with continuously varying sizes.
Radiation-Spray Coupling for Realistic Flow Configurations
NASA Technical Reports Server (NTRS)
El-Asrag, Hossam; Iannetti, Anthony C.
2011-01-01
Three Large Eddy Simulations (LES) for a lean-direct injection (LDI) combustor are performed and compared. In addition to the cold flow simulation, the effect of radiation coupling with the multi-physics reactive flow is analyzed. The flame let progress variable approach is used as a subgrid combustion model combined with a stochastic subgrid model for spray atomization and an optically thin radiation model. For accurate chemistry modeling, a detailed Jet-A surrogate mechanism is utilized. To achieve realistic inflow, a simple recycling technique is performed at the inflow section upstream of the swirler. Good comparison is shown with the experimental data mean and root mean square profiles. The effect of combustion is found to change the shape and size of the central recirculation zone. Radiation is found to change the spray dynamics and atomization by changing the heat release distribution and the local temperature values impacting the evaporation process. The simulation with radiation modeling shows wider range of droplet size distribution by altering the evaporation rate. The current study proves the importance of radiation modeling for accurate prediction in realistic spray combustion configurations, even for low pressure systems.
Robb, Matthew L; Böhning, Dankmar
2011-02-01
Capture–recapture techniques have been used for considerable time to predict population size. Estimators usually rely on frequency counts for numbers of trappings; however, it may be the case that these are not available for a particular problem, for example if the original data set has been lost and only a summary table is available. Here, we investigate techniques for specific examples; the motivating example is an epidemiology study by Mosley et al., which focussed on a cholera outbreak in East Pakistan. To demonstrate the wider range of the technique, we also look at a study for predicting the long-term outlook of the AIDS epidemic using information on number of sexual partners. A new estimator is developed here which uses the EM algorithm to impute unobserved values and then uses these values in a similar way to the existing estimators. The results show that a truncated approach – mimicking the Chao lower bound approach – gives an improved estimate when population homogeneity is violated.
NASA Astrophysics Data System (ADS)
Stacey, Peter; Thorpe, Andrew; Roberts, Paul; Butler, Owen
2018-06-01
Inhalation of respirable crystalline silica (RCS) can cause diseases including silicosis and cancer. Levels of RCS close to an emission source are measured but little is known about the wider ambient exposure from industry emissions or natural sources. The aim of this work is to report the RCS concentrations obtained from a variety of ambient environments using a new mobile respirable (PM4) sampler. A mobile battery powered high flow rate (52 L min-1) sampler was developed and evaluated for particulate aerosol sampling employing foams to select the respirable particle size fraction. Sampling was conducted in the United Kingdom at site boundaries surrounding seven urban construction and demolition and five sand quarry sites. These are compared with data from twelve urban aerosol samples and from repeat measurements from a base line study at a single rural site. The 50% particle size penetration (d50) through the foam was 4.3 μm. Over 85% of predict bias values were with ±10% of the respirable convention, which is based on a log normal curve. Results for RCS from all construction and quarry activities are generally low with a 95 th percentile of 11 μg m-3. Eighty percent of results were less than the health benchmark value of 3 μg m-3 used in some states in America for ambient concentrations. The power cutting of brick and the largest demolition activities gave the highest construction levels. Measured urban background RCS levels were typically below 0.3 μg m-3 and the median RCS level, at a rural background location, was 0.02 μg m-3. These reported ambient RCS concentrations may provide useful baseline values to assess the wider impact of fugitive, RCS containing, dust emissions into the wider environment.
Maddock, Jane; Wulaningsih, Wahyu; Hardy, Rebecca
2017-07-05
Body size, nutrition and socioeconomic position (SEP) in early life have been associated with a range of later life health outcomes. Epigenetic regulation is one mechanism through which these early life factors may impact later life health. The aim of this review protocol is to outline procedures to document the influence of body size, nutrition and SEP in early life on the epigenome. MEDLINE, Embase and BIOSIS will be systematically searched using pre-defined keywords. Additional studies will be identified through manual searching of reference lists. Two independent researchers will assess the eligibility and quality of each study, with disagreements being resolved through discussion or a third reviewer. Studies will be included if they have epigenetic markers measured either at the same time as, or after, the early life exposure and, have a measure of body size, nutrition or SEP in early life (up to 12 years), are in the English language and are from a sample of community-dwelling participants. This protocol will be used to collate the evidence for the effect of early life factors on the epigenome. Findings will form a component of a wider research study examining epigenetic responses to exposures in early life and over the life course and its impact on healthy ageing using data from population-based cohort studies. PROSPERO CRD42016050193.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azarkh, Eugene; Robinson, Erin; Hirunkanokpun, Supanee
Mosquito densonucleosis viruses synthesize two non-structural proteins, NS1 and NS2. While NS1 has been studied relatively well, little is known about NS2. Antiserum was raised against a peptide near the N-terminus of NS2, and used to conduct Western blot analysis and immuno-fluorescence assays. Western blots revealed a prominent band near the expected size (41 kDa). Immuno-fluorescence studies of mosquito cells transfected with AeDNV indicate that NS2 has a wider distribution pattern than does NS1, and the distribution pattern appears to be a function of time post-infection. Nuclear localization of NS2 requires intact C-terminus but does not require additional viral proteins.more » Mutations ranging from complete NS2 knock-out to a single missense amino acid substitution in NS2 can significantly reduce viral replication and production of viable progeny.« less
Proton beam radiotherapy of uveal melanoma
Damato, Bertil; Kacperek, Andrzej; Errington, Doug; Heimann, Heinrich
2013-01-01
Proton beam radiotherapy of uveal melanoma can be administered as primary treatment, as salvage therapy for recurrent tumor, and as neoadjuvant therapy prior to surgical resection. The physical properties of proton beams make it possible to deliver high-doses of radiation to the tumor with relative sparing of adjacent tissues. This form of therapy is effective for a wider range of uveal melanoma than any other modality, providing exceptionally-high rates of local tumor control. This is particularly the case with diffuse iris melanomas, many of which are unresectable. The chances of survival, ocular conservation, visual preservation and avoidance of iatrogenic morbidity depend greatly on the tumor size, location and extent. When treating any side-effects and/or complications, it is helpful to consider whether these are the result of collateral damage or persistence of the irradiated tumor (‘toxic tumor syndrome’). PMID:24227980
Shen, Yu-Chu; Eggleston, Karen; Lau, Joseph; Schmid, Christopher H
2007-01-01
This study applies meta-analytic methods to conduct a quantitative review of the empirical literature on hospital ownership since 1990. We examine four financial outcomes across 40 studies: cost, revenue, profit margin, and efficiency. We find that variation in the magnitudes of ownership effects can be explained by a study's research focus and methodology. Studies using empirical methods that control for few confounding factors tend to find larger differences between for-profit and not-for-profit hospitals than studies that control for a wider range of confounding factors. Functional form and sample size also matter. Failure to apply log transformation to highly skewed expenditure data yields misleadingly large estimated differences between for-profits and not-for-profits. Studies with fewer than 200 observations also produce larger point estimates and wide confidence intervals.
NASA Astrophysics Data System (ADS)
Cain, Michelle
2016-04-01
I will discuss my experience co-ordinating a range of communication activities for a multi-university research programme called Methane in the Arctic: Measurements and Modelling. The project included ground- and aircraft-based fieldwork in the European Arctic, as well as computer modelling. Our communication activities included: our own field blog (www.arcticmethane.wordpress.com), which was syndicated to the Scientific American Expeditions blog; writing articles for other blogs with a wider audience than our own; use of twitter; and podcasting our field work. The grand finale to our communications work was a live event at a science festival, in which we took the audience along with us on a recreated research flight, complete with a life-size mock up of a section of our research aircraft. I will discuss my experiences of these forms of communication, and give an evaluation of their successes and failures.
Contributed review: quantum cascade laser based photoacoustic detection of explosives.
Li, J S; Yu, B; Fischer, H; Chen, W; Yalin, A P
2015-03-01
Detecting trace explosives and explosive-related compounds has recently become a topic of utmost importance for increasing public security around the world. A wide variety of detection methods and an even wider range of physical chemistry issues are involved in this very challenging area. Optical sensing methods, in particular mid-infrared spectrometry techniques, have a great potential to become a more desirable tools for the detection of explosives. The small size, simplicity, high output power, long-term reliability make external cavity quantum cascade lasers (EC-QCLs) the promising spectroscopic sources for developing analytical instrumentation. This work reviews the current technical progress in EC-QCL-based photoacoustic spectroscopy for explosives detection. The potential for both close-contact and standoff configurations using this technique is completely presented over the course of approximately the last one decade.
Contributed Review: Quantum cascade laser based photoacoustic detection of explosives
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, J. S., E-mail: jingsong-li@ahu.edu.cn; Yu, B.; Fischer, H.
2015-03-15
Detecting trace explosives and explosive-related compounds has recently become a topic of utmost importance for increasing public security around the world. A wide variety of detection methods and an even wider range of physical chemistry issues are involved in this very challenging area. Optical sensing methods, in particular mid-infrared spectrometry techniques, have a great potential to become a more desirable tools for the detection of explosives. The small size, simplicity, high output power, long-term reliability make external cavity quantum cascade lasers (EC-QCLs) the promising spectroscopic sources for developing analytical instrumentation. This work reviews the current technical progress in EC-QCL-based photoacousticmore » spectroscopy for explosives detection. The potential for both close-contact and standoff configurations using this technique is completely presented over the course of approximately the last one decade.« less
Topological phase in a two-dimensional metallic heavy-fermion system
NASA Astrophysics Data System (ADS)
Yoshida, Tsuneya; Peters, Robert; Fujimoto, Satoshi; Kawakami, Norio
2013-04-01
We report on a topological insulating state in a heavy-fermion system away from half filling, which is hidden within a ferromagnetic metallic phase. In this phase, the cooperation of the RKKY interaction and the Kondo effect, together with the spin-orbit coupling, induces a spin-selective gap, bringing about topologically nontrivial properties. This topological phase is robust against a change in the chemical potential in a much wider range than the gap size. We analyze these remarkable properties by using dynamical mean field theory and the numerical renormalization group. Its topological properties support a gapless chiral edge mode, which exhibits a non-Tomonaga-Luttinger liquid behavior due to the coupling with bulk ferromagnetic spin fluctuations. We also propose that the effects of the spin fluctuations on the edge mode can be detected via the NMR relaxation time measurement.
Goldblatt, Colin
2015-05-01
There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds." I map these as a function of solar constant for planets ranging in size from Mars-sized to 10 Earth-mass. The states are as follows: globally ice covered (Ts ⪅ 245 K), cold and damp (270 ⪅ Ts ⪅ 290 K), hot and moist (350 ⪅ Ts ⪅ 550 K), and very hot and dry (Tsx2A86;900 K). No stable climate exists for 290 ⪅ T s ⪅ 350 K or 550 ⪅ Ts ⪅ 900 K. The union of hot moist and cold damp climates describes the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong nonlinearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surface, so more thermal radiation is emitted and more sunlight absorbed (the former dominates). The atmospheres of small planets expand more due to weaker gravity; the effective runaway greenhouse threshold is about 35 W m(-2) higher for Mars, 10 W m(-2) higher for Earth or Venus, but only a few W m(-2) higher for a 10 Earth-mass planet. There is an underlying (expansion-neglected) trend of increasing runaway greenhouse threshold with planetary size (40 W m(-2) higher for a 10 Earth-mass planet than for Mars). Summing these opposing trends means that Venus-sized (or slightly smaller) planets are most susceptible to a runaway greenhouse. The habitable zone for pure water atmospheres is very narrow, with an insolation range of 0.07 times the solar constant. A wider habitable zone requires background gas and greenhouse gas: N2 and CO2 on Earth, which are biologically controlled. Thus, habitability depends on inhabitance.
Estimation of portion size in children's dietary assessment: lessons learnt.
Foster, E; Adamson, A J; Anderson, A S; Barton, K L; Wrieden, W L
2009-02-01
Assessing the dietary intake of young children is challenging. In any 1 day, children may have several carers responsible for providing them with their dietary requirements, and once children reach school age, traditional methods such as weighing all items consumed become impractical. As an alternative to weighed records, food portion size assessment tools are available to assist subjects in estimating the amounts of foods consumed. Existing food photographs designed for use with adults and based on adult portion sizes have been found to be inappropriate for use with children. This article presents a review and summary of a body of work carried out to improve the estimation of portion sizes consumed by children. Feasibility work was undertaken to determine the accuracy and precision of three portion size assessment tools; food photographs, food models and a computer-based Interactive Portion Size Assessment System (IPSAS). These tools were based on portion sizes served to children during the National Diet and Nutrition Survey. As children often do not consume all of the food served to them, smaller portions were included in each tool for estimation of leftovers. The tools covered 22 foods, which children commonly consume. Children were served known amounts of each food and leftovers were recorded. They were then asked to estimate both the amount of food that they were served and the amount of any food leftover. Children were found to estimate food portion size with an accuracy approaching that of adults using both the food photographs and IPSAS. Further development is underway to increase the number of food photographs and to develop IPSAS to cover a much wider range of foods and to validate the use of these tools in a 'real life' setting.
NASA Astrophysics Data System (ADS)
Ma, Q.; Su, Y.; Tao, S.; Guo, Q.
2016-12-01
Trees in the Sierra Nevada (SN) forests are experiencing rapid changes due to human disturbances and climatic changes. An improved monitoring of tree growth and understanding of how tree growth responses to different impact factors, such as tree competition, forest density, topographic and hydrologic conditions, are urgently needed in tree growth modeling. Traditional tree growth modeling mainly relied on field survey, which was highly time-consuming and labor-intensive. Airborne Light detection and ranging System (ALS) is increasingly used in forest survey, due to its high efficiency and accuracy in three-dimensional tree structure delineation and terrain characterization. This study successfully detected individual tree growth in height (ΔH), crown area (ΔA), and crown volume (ΔV) over a five-year period (2007-2012) using bi-temporal ALS data in two conifer forest areas in SN. We further analyzed their responses to original tree size, competition indices, forest structure indices, and topographic environmental parameters at individual tree and forest stand scales. Our results indicated ΔH was strongly sensitive to topographic wetness index; whereas ΔA and ΔV were highly responsive to forest density and original tree sizes. These ALS based findings in ΔH were consistent with field measurements. Our study demonstrated the promising potential of using bi-temporal ALS data in forest growth measurements and analysis. A more comprehensive study over a longer temporal period and a wider range of forest stands would give better insights into tree growth in the SN, and provide useful guides for forest growth monitoring, modeling, and management.
Evaporation in the young solar nebula as the origin of 'just-right' melting of chondrules
Cohen; Hewins; Yu
2000-08-10
Chondrules are millimetre-sized, solidified melt spherules formed in the solar nebula by an early widespread heating event of uncertain nature. They were accreted into chondritic asteroids, which formed about 4.56 billion years ago and have not experienced melting or differentiation since that time. Chondrules have diverse chemical compositions, corresponding to liquidus temperatures in the range 1,350-1,800 degrees C. Most chondrules, however, show porphyritic textures (consisting of large crystals in a distinctly finer grained or glassy matrix), indicative of melting within the narrow range 0-50 degrees C below the liquidus. This suggests an unusual heating mechanism for chondrule precursors, which would raise each individual chondrule to just the right temperature (particular to individual bulk composition) in order to form porphyritic textures. Here we report the results of isothermal melting of a chondritic composition at nebular pressures. Our results suggest that evaporation stabilizes porphyritic textures over a wider range of temperatures below the liquidus (about 200 degrees C) than previously believed, thus removing the need for individual chondrule temperature buffering. In addition, we show that evaporation explains many chondrule bulk and mineral compositions that have hitherto been difficult to understand.
Nuclear structure of bound states of asymmetric dark matter
NASA Astrophysics Data System (ADS)
Gresham, Moira I.; Lou, Hou Keong; Zurek, Kathryn M.
2017-11-01
Models of asymmetric dark matter (ADM) with a sufficiently attractive and long-range force give rise to stable bound objects, analogous to nuclei in the Standard Model, called nuggets. We study the properties of these nuggets and compute their profiles and binding energies. Our approach, applicable to both elementary and composite fermionic ADM, utilizes relativistic mean field theory, and allows a more systematic computation of nugget properties, over a wider range of sizes and force mediator masses, compared to previous literature. We identify three separate regimes of nugget property behavior corresponding to (1) nonrelativistic and (2) relativistic constituents in a Coulomb-like limit, and (3) saturation in an anti-Coulomb limit when the nuggets are large compared to the force range. We provide analytical descriptions for nuggets in each regime. Through numerical calculations, we are able to confirm our analytic descriptions and also obtain smooth transitions for the nugget profiles between all three regimes. We also find that over a wide range of parameter space, the binding energy in the saturation limit is an O (1 ) fraction of the constituent's mass, significantly larger than expectations in the nonrelativistic case. In a companion paper, we apply our results to the synthesis of ADM nuggets in the early Universe.
Braham, Melissa A.; Miller, Tricia A.; Duerr, Adam E.; Lanzone, Michael J.; Fesnock, Amy; LaPre, Larry; Driscoll, Daniel; Katzner, Todd E.
2015-01-01
Renewable energy is expanding quickly with sometimes dramatic impacts to species and ecosystems. To understand the degree to which sensitive species may be impacted by renewable energy projects, it is informative to know how much space individuals use and how that space may overlap with planned development. We used global positioning system–global system for mobile communications (GPS-GSM) telemetry to measure year-round movements of golden eagles (Aquila chrysaetos) from the Mojave Desert of California, USA. We estimated monthly space use with adaptive local convex hulls to identify the temporal and spatial scales at which eagles may encounter renewable energy projects in the Desert Renewable Energy Conservation Plan area. Mean size of home ranges was lowest and least variable from November through January and greatest in February–March and May–August. These monthly home range patterns coincided with seasonal variation in breeding ecology, habitat associations, and temperature. The expanded home ranges in hot summer months included movements to cooler, prey-dense, mountainous areas characterized by forest, grasslands, and scrublands. Breeding-season home ranges (October–May) included more lowland semi-desert and rock vegetation. Overlap of eagle home ranges and focus areas for renewable energy development was greatest when eagle home ranges were smallest, during the breeding season. Golden eagles in the Mojave Desert used more space and a wider range of habitat types than expected and renewable energy projects could affect a larger section of the regional population than was previously thought.
Archer, John; Benson, David
2008-01-01
In three studies, Resource Holding Power (RHP) and provocation were manipulated in scenarios involving a young person in a bar with friends. In Study 1, teenage men reported lower likelihood of responding with physical aggression when insulted as levels of three RHP cues (size, allies and reputation) increased, effects that were accentuated by combinations of high-RHP cues; in the second part of this study, they consistently rated an insult to their girlfriend as the most provoking from a range of possible provocations, chosen on theoretical and empirical grounds. Study 2 replicated the results of the first part of Study 1 in samples of men and women in their twenties, although the effects were weaker at low levels of RHP. Study 3 combined a high- or low-provoking event, with low, medium or high RHP, and a wider range of response choices. As expected, direct aggression increased as provocation increased and RHP decreased. Delayed aggressive responses, including revenge fantasies, were highest in response to high provocation and high RHP. Findings are discussed in relation to theoretical models of aggressive motivation. (c) 2007 Wiley-Liss, Inc.
Overseas Varietal Analysis 2009 Crop Soft Red Winter Wheat
USDA-ARS?s Scientific Manuscript database
Each customer in the survey has a preference for specific protein targets. Grain shipments within those protein ranges may perform better than individual varieties that often have a wider range in protein than normally observed in pooled cargos of commercial grain shipments. The feedback on protei...
Experiences of Action Leaning in Two SME Business Support Programmes
ERIC Educational Resources Information Center
Smith, Laurie
2009-01-01
Action learning sets are used by Lancaster University Management School's Institute for Entrepreneurship and Enterprise Development to provide business support to owner managers of small to medium sized enterprises (SMEs). This paper compares the experiences of participants and facilitator of two programmes: one part of a wider programme of…
... that they are embarrassed by in public. The parents' own temperament, usual mood, and daily pressures will also influence how they interpret the child's behavior. Easygoing parents may accept a wider range ...
Weapon Possession Among College Students: A Study From a Midwestern University.
Jang, Hyunseok; Kang, Ji Hyon; Dierenfeldt, Rick; Lindsteadt, Greg
2015-10-01
Weapon possession on college campuses causes great concern, but there remains a lack of research examining the determinants of this phenomenon. Previous studies addressing weapon possession have primarily focused on either K-12 or the general adult population. Unlike previous studies, this study examined the weapon possession among college students using data collected from a mid-sized university in Missouri, and 451 students participated. Weapon possession and other theoretical factors were measured through the self-administered survey. Logistical regression analysis revealed that weapon socialization was the most significant factor in predicting student weapon carrying. Also, gender and age were significant factors in explaining campus-based weapon possession. This research has a limitation with generalizability because the data were collected from only a single university with convenient sampling. Future studies need to cover a wider range of college students from a variety of different universities with random sampling. © The Author(s) 2014.
Investigation on the modification behavior of A356.2 alloy with Yb-La composite modifier
NASA Astrophysics Data System (ADS)
Zhang, Shaochen; Leng, Jinfeng; Wang, Zhibin; Wang, Qi; Shao, Yuewen; Teng, Xinying
2018-01-01
In this work, an investigation was conducted to evaluate the influence of the Yb + La addition on the microstructures and mechanical properties of A356.2 alloy. The results show that the the grain size was refined and morphological structure of Si changed from needle-like to fine spheroidal particle by adding Yb + La. The eutectic temperature decreased from 589 °C to 581 °C and the freezing range of primary α-Al become wider after adding Yb + La. The mechanical properties showed great improvement after T6 heat treatment. The ultimate tensile strength and microhardness of the composites were increased to 279.0 MPa and 99.2 HB after T6 heat treatment which increased by 28.2% and 47.3%, respectively. The fracture mechanism was analyzed using the scanning electron microscopy and proved to be a transgranular/intergranular fracture modes.
NASA Technical Reports Server (NTRS)
Butler, R.; Williams, F. W.
1992-01-01
A computer program for obtaining the optimum (least mass) dimensions of the kind of prismatic assemblies of laminated, composite plates which occur in advanced aerospace construction is described. Rigorous buckling analysis (derived from exact member theory) and a tailored design procedure are used to produce designs which satisfy buckling and material strength constraints and configurational requirements. Analysis is two to three orders of magnitude quicker than FEM, keeps track of all the governing modes of failure and is efficiently adapted to give sensitivities and to maintain feasibility. Tailoring encourages convergence in fewer sizing cycles than competing programs and permits start designs which are a long way from feasible and/or optimum. Comparisons with its predecessor, PASCO, show that the program is more likely to produce an optimum, will do so more quickly in some cases, and remains accurate for a wider range of problems.
Pattern selection in an anisotropic Hele-Shaw cell
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCloud, K.V.; Maher, J.V.
1995-02-01
The selection of steady-state viscous fingers has been measured in Hele-Shaw cells that are perturbed by having rectangular and square lattices etched on one of their plates. The strength of the perturbation was varied by varying the cell gap, and over a wide range of observable tip velocities this local perturbation was also made microscopic in the sense that the capillary length of the flow was large in comparison to the cell size of the underlying lattice. Above threshold the microscopic perturbation results in the selection of wider fingers than those selected in the unperturbed flow for all channel orientationsmore » in the experiment. All observed solutions are symmetric, centered in the channel, and have the relation between tip curvature and finger width expected of members of the Saffman-Taylor family of solutions. Selected solutions narrow again at tip velocities where the perturbations can no longer be considered microscopic.« less
Breedy, Odalisca; Guzman, Hector M
2018-01-05
The genus Adelogorgia is distinguished from other holaxonians in having conspicuously ornamented double-disc sclerites and leaf clubs in the coenenchyme, and non-mineralised axis cores. The two eastern Pacific species currently recognised as Adelogorgia are diagnosed and illustrated. Three new species for the genus are described from new localities and depth ranges. Analysis of external and internal characters, especially sclerite colours and sizes, and colony colour, shape and branching, allows separating the species. An identification key to the five species is provided, as well as a character table for comparisons. This study was based on newly collected specimens from 50 to 200 m deep, and re-examination of all historical material. We conclude that the genus comprises five valid species with a wider distribution than previously reported. This research is a contribution to the octocoral systematics and biodiversity from mesophotic and deep waters.
Coordinating and planning for human sexuality education.
Jenkins, D M
1981-04-01
The coordinator provides parent education, teacher and staff inservice training, team-teaching experiences, student counseling and a broad range of support activities related to the wider community as well as to the schools involved. The need for a coordinator for programs may depend on size and/or diversity of the school population, professional readiness of teachers and types of programs to be implemented. Despite the advances made in the Pomona program, there continue to be such problems as occasional resistance from special interest groups, administrators and school staff, individual instructors' personal value conflicts, transitional nature of student population and turnover in teacher personnel. A coordinator for sexuality programs is certainly not a total remedy for such problems in all school districts; but as an essential element in the solution of those problems, he/she provides an approach which will help school districts in initiating and implementing programs with a greater degree of success.
USDA-ARS?s Scientific Manuscript database
Multiple introductions of an exotic species can facilitate invasion success by allowing for a wider range of expressed trait values in the adventive range. Brazilian peppertree is an invasive shrub that was introduced into Florida multiple times and has subsequently hybridized, resulting in three di...
High-Quality Traineeships: Identifying What Works. Good Practice Guide
ERIC Educational Resources Information Center
National Centre for Vocational Education Research (NCVER), 2009
2009-01-01
Traineeships were introduced alongside apprenticeships to increase the reach of contracted training to a wider range of occupations and industries and to a broader range of learners (particularly women) and to improve the labour market prospects of young people. Traineeships have given hundreds of thousands of Australians access to nationally…
Computer Simulation Utilization in Graduate Behavior Therapy Training.
ERIC Educational Resources Information Center
Lambert, Matthew E.; And Others
Practicum experiences are thought to be a time for honing clinical skills and integrating content course material with clinical practice. Often, however, the range of clinical problems encountered during practica is restricted, limiting the variety of learning experiences available to practicum group members. To provide a wider range of…
Numerical investigation on the Ångström exponent of black carbon aerosol
NASA Astrophysics Data System (ADS)
Li, Ji; Liu, Chao; Yin, Yan; Kumar, K. Raghavendra
2016-04-01
Black carbon (BC) plays an important role on the global and regional climate, whereas there are significant uncertainties on its optical properties. Among various optical properties, the Ångström exponent (AE) indicates the spectral variation of the particle-optic interaction and is widely used to understand the aerosol properties. We consider the influence of BC geometry on its optical properties and assess the sensitivity of the AE to particle geometry and size distribution. The fractal aggregates with different fractal dimensions are used to represent realistic BC particles, and popular equivalent volume spherical and spheroidal models are also considered for comparison. Even if the fractal aggregates become highly compact and spherical, their optical properties are still significantly different from those of equivalent volume spheres or spheroids. Meanwhile, the Rayleigh-Debye-Gans approximation can hardly provide accurate results for all optical quantities of aggregates with different dimensions. The extinction Ångström exponent (EAE) and absorption Ångström exponent (AAE) are sensitive to both particle geometry and size distribution. With BC becoming more compact (from fractal aggregate to spheroid and to sphere), the AE becomes more sensitive to particle size distribution. The EAE and AAE of aggregates with different size distributions vary between 1.10-1.63 and 0.87-1.50, respectively, whereas those of the spheres or spheroids have wider ranges. Furthermore, the AE at smaller wavelengths (between 0.35 µm and 0.55 µm) is more sensitive to geometry and size distribution than that given by optical properties at larger wavelengths (between 0.55 µm and 0.88 µm).
Preston, Catherine; Ehrsson, H. Henrik
2014-01-01
Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology. PMID:24465698
Surface facial modelling and allometry in relation to sexual dimorphism.
Velemínská, J; Bigoni, L; Krajíček, V; Borský, J; Šmahelová, D; Cagáňová, V; Peterka, M
2012-04-01
Sexual dimorphism is responsible for a substantial part of human facial variability, the study of which is essential for many scientific fields ranging from evolution to special biomedical topics. Our aim was to analyse the relationship between size variability and shape facial variability of sexual traits in the young adult Central European population and to construct average surface models of adult males and females. The method of geometric morphometrics allowed not only the identification of dimorphic traits, but also the evaluation of static allometry and the visualisation of sexual facial differences. Facial variability in the studied sample was characterised by a strong relationship between facial size and shape of sexual dimorphic traits. Large size of face was associated with facial elongation and vice versa. Regarding shape sexual dimorphic traits, a wide, vaulted and high forehead in combination with a narrow and gracile lower face were typical for females. Variability in shape dimorphic traits was smaller in females compared to males. For female classification, shape sexual dimorphic traits are more important, while for males the stronger association is with face size. Males generally had a closer inter-orbital distance and a deeper position of the eyes in relation to the facial plane, a larger and wider straight nose and nostrils, and more massive lower face. Using pseudo-colour maps to provide a detailed schematic representation of the geometrical differences between the sexes, we attempted to clarify the reasons underlying the development of such differences. Copyright © 2012 Elsevier GmbH. All rights reserved.
NASA Technical Reports Server (NTRS)
Hansell, R. A., Jr.; Reid, J. S.; Tsay, S. C.; Roush, T. L.; Kalashnikova, O. V.
2011-01-01
To determine a plausible range of mass extinction efficiencies (MEE) of terrestrial atmospheric dust from the near to thermal IR, sensitivity analyses are performed over an extended range of dust microphysical and chemistry perturbations. The IR values are subsequently compared to those in the near-IR, to evaluate spectral relationships in their optical properties. Synthesized size distributions consistent with measurements, model particle size, while composition is defined by the refractive indices of minerals routinely observed in dust, including the widely used OPAC/Hess parameterization. Single-scattering properties of representative dust particle shapes are calculated using the T-matrix, Discrete Dipole Approximation and Lorenz-Mie light-scattering codes. For the parameterizations examined, MEE ranges from nearly zero to 1.2 square meters per gram, with the higher values associated with non-spheres composed of quartz and gypsum. At near-IR wavelengths, MEE for non-spheres generally exceeds those for spheres, while in the thermal IR, shape-induced changes in MEE strongly depend on volume median diameter (VMD) and wavelength, particularly for MEE evaluated at the mineral resonant frequencies. MEE spectral distributions appear to follow particle geometry and are evidence for shape dependency in the optical properties. It is also shown that non-spheres best reproduce the positions of prominent absorption peaks found in silicates. Generally, angular particles exhibit wider and more symmetric MEE spectral distribution patterns from 8-10 micrometers than those with smooth surfaces, likely due to their edge-effects. Lastly, MEE ratios allow for inferring dust optical properties across the visible-IR spectrum. We conclude the MEE of dust aerosol are significant for the parameter space investigated, and are a key component for remote sensing applications and the study of direct aerosol radiative effects.
Fast Constrained Spectral Clustering and Cluster Ensemble with Random Projection
Liu, Wenfen
2017-01-01
Constrained spectral clustering (CSC) method can greatly improve the clustering accuracy with the incorporation of constraint information into spectral clustering and thus has been paid academic attention widely. In this paper, we propose a fast CSC algorithm via encoding landmark-based graph construction into a new CSC model and applying random sampling to decrease the data size after spectral embedding. Compared with the original model, the new algorithm has the similar results with the increase of its model size asymptotically; compared with the most efficient CSC algorithm known, the new algorithm runs faster and has a wider range of suitable data sets. Meanwhile, a scalable semisupervised cluster ensemble algorithm is also proposed via the combination of our fast CSC algorithm and dimensionality reduction with random projection in the process of spectral ensemble clustering. We demonstrate by presenting theoretical analysis and empirical results that the new cluster ensemble algorithm has advantages in terms of efficiency and effectiveness. Furthermore, the approximate preservation of random projection in clustering accuracy proved in the stage of consensus clustering is also suitable for the weighted k-means clustering and thus gives the theoretical guarantee to this special kind of k-means clustering where each point has its corresponding weight. PMID:29312447
NASA Astrophysics Data System (ADS)
Zhang, Juanjuan; Kang, Yan; Yu, Yang; Gao, Yuanwen
2017-01-01
In this study, a new kind of magnetoelectric (ME) structure is designed with Terfenol-D, PZT-5A and nonmagnetic and nonelectric trestle. The configuration of this ME structure presents "A-line" type, PZT-5A and Terfenol-D are respectively bonded with the trestles, which adopt the knuckle joint assembly. Differently from the conventional ME layered structure, in the new structure, the deformation of the PZT-5A of larger size is driven by a Terfenol-D layer of smaller size at an external magnetic field. Since the driven force is applied at the ends of piezoelectric layer through the trestles, the whole piezoelectric layer can be completely stretched or compressed, and the larger voltage should be induced. For the new ME structure with mica trestle, the maximum value of αE is twice higher than that for the conventional laminated ME structure. Furthermore, a wider range of response frequency is also observed in this structure. For the new ME structure with ABS trestle, the experimental results indicate that the maximum ME voltage coefficient is measured as high as 31.85 V/cm Oe at 405 Oe.
Recent Developments in Grid Generation and Force Integration Technology for Overset Grids
NASA Technical Reports Server (NTRS)
Chan, William M.; VanDalsem, William R. (Technical Monitor)
1994-01-01
Recent developments in algorithms and software tools for generating overset grids for complex configurations are described. These include the overset surface grid generation code SURGRD and version 2.0 of the hyperbolic volume grid generation code HYPGEN. The SURGRD code is in beta test mode where the new features include the capability to march over a collection of panel networks, a variety of ways to control the side boundaries and the marching step sizes and distance, a more robust projection scheme and an interpolation option. New features in version 2.0 of HYPGEN include a wider range of boundary condition types. The code also allows the user to specify different marching step sizes and distance for each point on the surface grid. A scheme that takes into account of the overlapped zones on the body surface for the purpose of forces and moments computation is also briefly described, The process involves the following two software modules: MIXSUR - a composite grid generation module to produce a collection of quadrilaterals and triangles on which pressure and viscous stresses are to be integrated, and OVERINT - a forces and moments integration module.
Groom, Scott V C; Stevens, Mark I; Schwarz, Michael P
2014-06-22
The impacts of glacial cycles on the geographical distribution and size of populations have been explored for numerous terrestrial and marine taxa. However, most studies have focused on high latitudes, with only a few focused on the response of biota to the last glacial maximum (LGM) in equatorial regions. Here, we examine how population sizes of key bee fauna in the southwest Pacific archipelagos of Fiji, Vanuatu and Samoa have fluctuated over the Quaternary. We show that all three island faunas suffered massive population declines, roughly corresponding in time to the LGM, followed by rapid expansion post-LGM. Our data therefore suggest that Pleistocene climate change has had major impacts across a very broad tropical region. While other studies indicate widespread Holarctic effects of the LGM, our data suggest a much wider range of latitudes, extending to the tropics, where these climate change repercussions were important. As key pollinators, the inferred changes in these bee faunas may have been critical in the development of the diverse Pacific island flora. The magnitude of these responses indicates future climate change scenarios may have alarming consequences for Pacific island systems involving pollinator-dependent plant communities and agricultural crops.
Coos, booms, and hoots: The evolution of closed-mouth vocal behavior in birds.
Riede, Tobias; Eliason, Chad M; Miller, Edward H; Goller, Franz; Clarke, Julia A
2016-08-01
Most birds vocalize with an open beak, but vocalization with a closed beak into an inflating cavity occurs in territorial or courtship displays in disparate species throughout birds. Closed-mouth vocalizations generate resonance conditions that favor low-frequency sounds. By contrast, open-mouth vocalizations cover a wider frequency range. Here we describe closed-mouth vocalizations of birds from functional and morphological perspectives and assess the distribution of closed-mouth vocalizations in birds and related outgroups. Ancestral-state optimizations of body size and vocal behavior indicate that closed-mouth vocalizations are unlikely to be ancestral in birds and have evolved independently at least 16 times within Aves, predominantly in large-bodied lineages. Closed-mouth vocalizations are rare in the small-bodied passerines. In light of these results and body size trends in nonavian dinosaurs, we suggest that the capacity for closed-mouth vocalization was present in at least some extinct nonavian dinosaurs. As in birds, this behavior may have been limited to sexually selected vocal displays, and hence would have co-occurred with open-mouthed vocalizations. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.
Hang, Tian; Chen, Hui-Jiuan; Wang, Ji; Lin, Di-An; Wu, Jiangming; Liu, Di; Cao, Yuhong; Yang, Chengduan; Liu, Chenglin; Xiao, Shuai; Gu, Meilin; Pan, Shuolin; Wu, Mei X; Xie, Xi
2018-05-04
Dispersion of hydrophilic particles in non-polar media has many important applications yet remains difficult. Surfactant or amphiphilic functionalization was conventionally applied to disperse particles but is highly dependent on the particle/solvent system and may induce unfavorable effects and impact particle hydrophilic nature. Recently 2 μm size polystyrene microbeads coated with ZnO nanospikes have been reported to display anomalous dispersity in phobic media without using surfactant or amphiphilic functionalization. However, due to the lack of understanding whether this phenomenon was applicable to a wider range of conditions, little application has been derived from it. Here the anomalous dispersity phenomenons of hydrophilic microparticles covered with nanospikes were systematically assessed at various conditions including different particle sizes, material compositions, particle morphologies, solvent hydrophobicities, and surface polar groups. Microparticles were functionalized with nanospikes through hydrothermal route, followed by dispersity test in hydrophobic media. The results suggest nanospikes consistently prevent particle aggregation in various particle or solvent conditions, indicating the universal applicability of the anomalous dispersion phenomenons. This work provides insight on the anomalous dispersity of hydrophilic particles in various systems and offers potential application to use this method for surfactant-free dispersions.
NASA Astrophysics Data System (ADS)
Hang, Tian; Chen, Hui-Jiuan; Wang, Ji; Lin, Di-an; Wu, Jiangming; Liu, Di; Cao, Yuhong; Yang, Chengduan; Liu, Chenglin; Xiao, Shuai; Gu, Meilin; Pan, Shuolin; Wu, Mei X.; Xie, Xi
2018-05-01
Dispersion of hydrophilic particles in non-polar media has many important applications yet remains difficult. Surfactant or amphiphilic functionalization was conventionally applied to disperse particles but is highly dependent on the particle/solvent system and may induce unfavorable effects and impact particle hydrophilic nature. Recently 2 μm size polystyrene microbeads coated with ZnO nanospikes have been reported to display anomalous dispersity in phobic media without using surfactant or amphiphilic functionalization. However, due to the lack of understanding whether this phenomenon was applicable to a wider range of conditions, little application has been derived from it. Here the anomalous dispersity phenomenons of hydrophilic microparticles covered with nanospikes were systematically assessed at various conditions including different particle sizes, material compositions, particle morphologies, solvent hydrophobicities, and surface polar groups. Microparticles were functionalized with nanospikes through hydrothermal route, followed by dispersity test in hydrophobic media. The results suggest nanospikes consistently prevent particle aggregation in various particle or solvent conditions, indicating the universal applicability of the anomalous dispersion phenomenons. This work provides insight on the anomalous dispersity of hydrophilic particles in various systems and offers potential application to use this method for surfactant-free dispersions.
Weighing trees with lasers: advances, challenges and opportunities
Boni Vicari, M.; Burt, A.; Calders, K.; Lewis, S. L.; Raumonen, P.; Wilkes, P.
2018-01-01
Terrestrial laser scanning (TLS) is providing exciting new ways to quantify tree and forest structure, particularly above-ground biomass (AGB). We show how TLS can address some of the key uncertainties and limitations of current approaches to estimating AGB based on empirical allometric scaling equations (ASEs) that underpin all large-scale estimates of AGB. TLS provides extremely detailed non-destructive measurements of tree form independent of tree size and shape. We show examples of three-dimensional (3D) TLS measurements from various tropical and temperate forests and describe how the resulting TLS point clouds can be used to produce quantitative 3D models of branch and trunk size, shape and distribution. These models can drastically improve estimates of AGB, provide new, improved large-scale ASEs, and deliver insights into a range of fundamental tree properties related to structure. Large quantities of detailed measurements of individual 3D tree structure also have the potential to open new and exciting avenues of research in areas where difficulties of measurement have until now prevented statistical approaches to detecting and understanding underlying patterns of scaling, form and function. We discuss these opportunities and some of the challenges that remain to be overcome to enable wider adoption of TLS methods. PMID:29503726
Morphology, Reproduction and Diet in Australian and Papuan Death Adders (Acanthophis, Elapidae)
Shine, Richard; Spencer, Carol L.; Keogh, J. Scott
2014-01-01
Death adders (genus Acanthophis) differ from most other elapid snakes, and resemble many viperid snakes, in their thickset morphology and ambush foraging mode. Although these snakes are widely distributed through Australia and Papua New Guinea, their basic biology remains poorly known. We report morphological and ecological data based upon dissection of >750 museum specimens drawn from most of the range of the genus. Female death adders grow larger than conspecific males, to about the same extent in all taxa (20% in mean adult snout-vent length, = SVL). Most museum specimens were adult rather than juvenile animals, and adult males outnumbered females in all taxa except A. pyrrhus. Females have shorter tails (relative to SVL) than males, and longer narrower heads (relative to head length) in some but not all species. The southern A. antarcticus is wider-bodied (relative to SVL) than the other Australian species. Fecundity of these viviparous snakes was similar among taxa (mean litter sizes 8 to 14). Death adders encompass a broad range of ecological attributes, taking a wide variety of vertebrate prey, mostly lizards (55%), frogs and mammals (each 21%; based on 217 records). Dietary composition differed among species (e.g. frogs were more common in tropical than temperate-zone species), and shifted with snake body size (endotherms were taken by larger snakes) and sex (male death adders took more lizards than did females). Overall, death adders take a broader array of prey types, including active fast-moving taxa such as endotherms and large diurnal skinks, than do most other Australian elapids of similar body sizes. Ambush foraging is the key to capturing such elusive prey. PMID:24718608
Morphology, reproduction and diet in Australian and Papuan death adders (Acanthophis, Elapidae).
Shine, Richard; Spencer, Carol L; Keogh, J Scott
2014-01-01
Death adders (genus Acanthophis) differ from most other elapid snakes, and resemble many viperid snakes, in their thickset morphology and ambush foraging mode. Although these snakes are widely distributed through Australia and Papua New Guinea, their basic biology remains poorly known. We report morphological and ecological data based upon dissection of >750 museum specimens drawn from most of the range of the genus. Female death adders grow larger than conspecific males, to about the same extent in all taxa (20% in mean adult snout-vent length, = SVL). Most museum specimens were adult rather than juvenile animals, and adult males outnumbered females in all taxa except A. pyrrhus. Females have shorter tails (relative to SVL) than males, and longer narrower heads (relative to head length) in some but not all species. The southern A. antarcticus is wider-bodied (relative to SVL) than the other Australian species. Fecundity of these viviparous snakes was similar among taxa (mean litter sizes 8 to 14). Death adders encompass a broad range of ecological attributes, taking a wide variety of vertebrate prey, mostly lizards (55%), frogs and mammals (each 21%; based on 217 records). Dietary composition differed among species (e.g. frogs were more common in tropical than temperate-zone species), and shifted with snake body size (endotherms were taken by larger snakes) and sex (male death adders took more lizards than did females). Overall, death adders take a broader array of prey types, including active fast-moving taxa such as endotherms and large diurnal skinks, than do most other Australian elapids of similar body sizes. Ambush foraging is the key to capturing such elusive prey.
Distribution and diversity of cytotypes in Dianthus broteri as evidenced by genome size variations.
Balao, Francisco; Casimiro-Soriguer, Ramón; Talavera, María; Herrera, Javier; Talavera, Salvador
2009-10-01
Studying the spatial distribution of cytotypes and genome size in plants can provide valuable information about the evolution of polyploid complexes. Here, the spatial distribution of cytological races and the amount of DNA in Dianthus broteri, an Iberian carnation with several ploidy levels, is investigated. Sample chromosome counts and flow cytometry (using propidium iodide) were used to determine overall genome size (2C value) and ploidy level in 244 individuals of 25 populations. Both fresh and dried samples were investigated. Differences in 2C and 1Cx values among ploidy levels within biogeographical provinces were tested using ANOVA. Geographical correlations of genome size were also explored. Extensive variation in chromosomes numbers (2n = 2x = 30, 2n = 4x = 60, 2n = 6x = 90 and 2n = 12x =180) was detected, and the dodecaploid cytotype is reported for the first time in this genus. As regards cytotype distribution, six populations were diploid, 11 were tetraploid, three were hexaploid and five were dodecaploid. Except for one diploid population containing some triploid plants (2n = 45), the remaining populations showed a single cytotype. Diploids appeared in two disjunct areas (south-east and south-west), and so did tetraploids (although with a considerably wider geographic range). Dehydrated leaf samples provided reliable measurements of DNA content. Genome size varied significantly among some cytotypes, and also extensively within diploid (up to 1.17-fold) and tetraploid (1.22-fold) populations. Nevertheless, variations were not straightforwardly congruent with ecology and geographical distribution. Dianthus broteri shows the highest diversity of cytotypes known to date in the genus Dianthus. Moreover, some cytotypes present remarkable internal genome size variation. The evolution of the complex is discussed in terms of autopolyploidy, with primary and secondary contact zones.
Wing shape allometry and aerodynamics in calopterygid damselflies: a comparative approach.
Outomuro, David; Adams, Dean C; Johansson, Frank
2013-06-07
Wing size and shape have important aerodynamic implications on flight performance. We explored how wing size was related to wing shape in territorial males of 37 taxa of the damselfly family Calopterygidae. Wing coloration was also included in the analyses because it is sexually and naturally selected and has been shown to be related to wing shape. We studied wing shape using both the non-dimensional radius of the second moment of wing area (RSM) and geometric morphometrics. Lower values of the RSM result in less energetically demanding flight and wider ranges of flight speed. We also re-analyzed previously published data on other damselflies and dragonflies. The RSM showed a hump-shaped relationship with wing size. However, after correcting for phylogeny using independent contrast, this pattern changed to a negative linear relationship. The basal genus of the study family, Hetaerina, was mainly driving that change. The obtained patterns were specific for the study family and differed from other damselflies and dragonflies. The relationship between the RSM and wing shape measured by geometric morphometrics was linear, but relatively small changes along the RSM axis can result in large changes in wing shape. Our results also showed that wing coloration may have some effect on RSM. We found that RSM showed a complex relationship with size in calopterygid damselflies, probably as a result of other selection pressures besides wing size per se. Wing coloration and specific behavior (e.g. courtship) are potential candidates for explaining the complexity. Univariate measures of wing shape such as RSM are more intuitive but lack the high resolution of other multivariate techniques such as geometric morphometrics. We suggest that the relationship between wing shape and size are taxa-specific and differ among closely-related insect groups.
Nonlinear dynamic range transformation in visual communication channels.
Alter-Gartenberg, R
1996-01-01
The article evaluates nonlinear dynamic range transformation in the context of the end-to-end continuous-input/discrete processing/continuous-display imaging process. Dynamic range transformation is required when we have the following: (i) the wide dynamic range encountered in nature is compressed into the relatively narrow dynamic range of the display, particularly for spatially varying irradiance (e.g., shadow); (ii) coarse quantization is expanded to the wider dynamic range of the display; and (iii) nonlinear tone scale transformation compensates for the correction in the camera amplifier.
Higher Education Institutions and Regional Mission: Lessons Learnt from the OECD Review Project
ERIC Educational Resources Information Center
Puukka, Jaana; Marmolejo, Francisco
2008-01-01
With the processes of globalization and localization, the local availability of knowledge and skills, and the transfer of technology and innovation to industry, small and medium-sized enterprises and the wider society have become increasingly important. In recent years, there have been many initiatives across Organization for Economic Cooperation…
Are autonomous cities our urban future?
Norman, Barbara
2018-05-29
Cities are rapidly expanding in size, wealth and power, with some now larger than nation states. Smart city solutions and strong global urban networks are developing to manage massive urban growth. However, cities exist within a wider system and it may take more than technological advances, innovation and city autonomy to develop a sustainable urban future.
Field evidence that ecosystem service projects support biodiversity and diversify options.
Goldman, Rebecca L; Tallis, Heather; Kareiva, Peter; Daily, Gretchen C
2008-07-08
Ecosystem service approaches to conservation are being championed as a new strategy for conservation, under the hypothesis that they will broaden and deepen support for biodiversity protection. Where traditional approaches focus on setting aside land by purchasing property rights, ecosystem service approaches aim to engage a much wider range of places, people, policies, and financial resources in conservation. This is particularly important given projected intensification of human impacts, with rapid growth in population size and individual aspirations. Here we use field research on 34 ecosystem service (ES) projects and 26 traditional biodiversity (BD) projects from the Western Hemisphere to test whether ecosystem service approaches show signs of realizing their putative potential. We find that the ES projects attract on average more than four times as much funding through greater corporate sponsorship and use of a wider variety of finance tools than BD projects. ES projects are also more likely to encompass working landscapes and the people in them. We also show that, despite previous concern, ES projects not only expand opportunities for conservation, but they are no less likely than BD projects to include or create protected areas. Moreover, they do not draw down limited financial resources for conservation but rather engage a more diverse set of funders. We also found, however, that monitoring of conservation outcomes in both cases is so infrequent that it is impossible to assess the effectiveness of either ES or BD approaches.
Field evidence that ecosystem service projects support biodiversity and diversify options
Goldman, Rebecca L.; Tallis, Heather; Kareiva, Peter; Daily, Gretchen C.
2008-01-01
Ecosystem service approaches to conservation are being championed as a new strategy for conservation, under the hypothesis that they will broaden and deepen support for biodiversity protection. Where traditional approaches focus on setting aside land by purchasing property rights, ecosystem service approaches aim to engage a much wider range of places, people, policies, and financial resources in conservation. This is particularly important given projected intensification of human impacts, with rapid growth in population size and individual aspirations. Here we use field research on 34 ecosystem service (ES) projects and 26 traditional biodiversity (BD) projects from the Western Hemisphere to test whether ecosystem service approaches show signs of realizing their putative potential. We find that the ES projects attract on average more than four times as much funding through greater corporate sponsorship and use of a wider variety of finance tools than BD projects. ES projects are also more likely to encompass working landscapes and the people in them. We also show that, despite previous concern, ES projects not only expand opportunities for conservation, but they are no less likely than BD projects to include or create protected areas. Moreover, they do not draw down limited financial resources for conservation but rather engage a more diverse set of funders. We also found, however, that monitoring of conservation outcomes in both cases is so infrequent that it is impossible to assess the effectiveness of either ES or BD approaches. PMID:18591667
Novel Analysis of the Multiwavelength Structure of the Relativistic Jet in Quasar 3C 273
NASA Astrophysics Data System (ADS)
Marchenko, Volodymyr; Harris, D. E.; Ostrowski, Michał; Stawarz, Łukasz; Bohdan, Artem; Jamrozy, Marek; Hnatyk, Bohdan
2017-07-01
We present a detailed analysis of the best-quality multiwavelength data gathered for the large-scale jet in the core-dominated quasar 3C 273. We analyze all the archival observations of the target with the Chandra X-ray Observatory, the far-ultraviolet observations with the Hubble Space Telescope, and the 8.4 GHz map obtained with the Very Large Array. In our study, we focus on investigating the morphology of the outflow at different frequencies, and therefore we apply various techniques for the image deconvolution, paying particular attention to a precise modeling of the Chandra and Hubble point-spread functions. We find that the prominent brightness enhancements in the X-ray and far-ultraviolet jet of 3C 273—the “knots”—are not point-like, and can be resolved transversely as extended features with sizes of about ≃ 0.5 {kpc}. Also, the radio outflow is wider than the deconvolved X-ray/ultraviolet jet. We have also found circumstantial evidence that the intensity peaks of the X-ray knots are located systematically upstream of the corresponding radio intensity peaks, with the projected spatial offsets along the jet ranging from ≲ 0.2 {kpc} up to ≃ 1 {kpc}. We discuss our findings in the wider context of multi-component models for the emission and structure of large-scale quasar jets, and speculate on the physical processes enabling an efficient acceleration of the emitting ultrarelativistic electrons along the entire jet length that exceeds 100 kpc.
Evaluation of the work of hospital districts' research ethics committees in Finland.
Halila, Ritva
2014-12-01
The main task of research ethics committees (RECs) is to assess research studies before their start. In this study, 24 RECs that evaluate medical research were sent questionnaires about their structure and functions. The RECs were divided into two separate groups: those working in university hospital districts (uRECs) and those in central hospital districts (non-uRECs). The two groups were different in many respects: the uRECs were bigger in size, covered a wider range of disciplines (both medical and non-medical), had better resources and more frequent and regular meetings. After the survey was performed and analysed, the Medical Research Act was amended so that only hospital districts with a medical faculty in their region had a duty to establish ethics committees. After the amendment, the number of RECs evaluating medical research in Finland decreased from 25 to 9. The ethics committees that remained had wider expertise and were better equipped already by the time of this survey. Only one non-uREC was continuing its work, and this was being done under the governance of a university hospital district. Simple measures were used for qualitative analysis of the work of RECs that evaluate medical research. These showed differences between RECs. This may be helpful in establishing an ethics committee network in a research field or administrational area. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Size-dependent impact of CNTs on dynamic properties of calmodulin
NASA Astrophysics Data System (ADS)
Gao, Jian; Wang, Liming; Kang, Seung-Gu; Zhao, Lina; Ji, Mingjuan; Chen, Chunying; Zhao, Yuliang; Zhou, Ruhong; Li, Jingyuan
2014-10-01
There are growing concerns about the biosafety of nanomaterials such as carbon nanotubes (CNTs) as their applications become more widespread. We report here a theoretical and experimental study of the binding of various sizes of CNTs [CNT (4,4), (5,5), (6,6) and (7,7)] to calmodulin (CaM) protein and, in particular, their impact on the Ca2+-dependent dynamic properties of CaM. Our simulations show that all the CNTs can plug into the hydrophobic binding pocket of Ca2+-bound CaM with binding affinities comparable with the native substrate M13 peptide. Even though CNT (4,4) shows a similar behavior to the M13 peptide in its dissociation from Ca2+-free CaM, wider CNTs still bind firmly to CaM, indicating a potential failure of Ca2+ regulation. Such a size-dependent impact of CNTs on the dynamic properties of CaM is a result of the excessively strong hydrophobic interactions between the wider CNTs and CaM. These simulation results were confirmed by circular dichroism spectroscopy, which showed that the secondary structures of CaM become insensitive to Ca2+ concentrations after the addition of CNTs. Our findings indicate that the cytotoxicity of nanoparticles to proteins arises not only from the inhibition of static protein structures (binding pockets), but also from impacts on their dynamic properties.There are growing concerns about the biosafety of nanomaterials such as carbon nanotubes (CNTs) as their applications become more widespread. We report here a theoretical and experimental study of the binding of various sizes of CNTs [CNT (4,4), (5,5), (6,6) and (7,7)] to calmodulin (CaM) protein and, in particular, their impact on the Ca2+-dependent dynamic properties of CaM. Our simulations show that all the CNTs can plug into the hydrophobic binding pocket of Ca2+-bound CaM with binding affinities comparable with the native substrate M13 peptide. Even though CNT (4,4) shows a similar behavior to the M13 peptide in its dissociation from Ca2+-free CaM, wider CNTs still bind firmly to CaM, indicating a potential failure of Ca2+ regulation. Such a size-dependent impact of CNTs on the dynamic properties of CaM is a result of the excessively strong hydrophobic interactions between the wider CNTs and CaM. These simulation results were confirmed by circular dichroism spectroscopy, which showed that the secondary structures of CaM become insensitive to Ca2+ concentrations after the addition of CNTs. Our findings indicate that the cytotoxicity of nanoparticles to proteins arises not only from the inhibition of static protein structures (binding pockets), but also from impacts on their dynamic properties. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr01623h
ERIC Educational Resources Information Center
Sinkinson, Anne J.
2006-01-01
The research examines the range of effects of obtaining Specialist School status in two contrasting mathematics and computing colleges, concentrating on the mathematics department. The positive impact of a wider range of technology was evident in both schools although the inherent pedagogical perspectives within each mathematics department…
Sorokin, Victoria; Alkhoury, Razan; Al-Rawabdeh, Sura; Houston, Ronald H; Thornton, David; Kerlin, Bryce; O'Brien, Sarah; Baker, Peter; Boesel, Carl; Uddin, Minhaj; Yin, Han; Kahwash, Samir
This study sought to determine delta granule normal ranges for children and to validate methodology for the appropriate diagnosis of delta granule deficiency (storage pool disease) by using the whole-mount technique in electron microscopy. Specimens obtained from 40 healthy volunteers (2 months of age through 21 years old, 21 females and 19 males) were tested. Results showed dense granules/platelet (DG/Plt) ranged from 1.78 to 5.25. The 5th percentile was 1.96 DG/Plt with an overall mean ± SEM 3.07 ± 0.12 DG/Plt. In comparison, a previously published lower cutoff value, 3.68 DG/Plt, was significantly higher than the mean from our volunteers (P < 0.0001). We found no variability in dense granules/platelet based on race or sex and no significant variation by age subgroup. Pending wider studies, the value of 2 DG/Plt is a more appropriate lower limit of normal. In the absence of wider studies (in healthy volunteers and patients), laboratories should consider establishing their own reference ranges.
NASA Technical Reports Server (NTRS)
Matano, T.; Machida, M.; Tsuchima, I.; Kawasumi, N.; Honda, K.; Hashimoto, K.; Martinic, N.; Zapata, J.; Navia, C. E.; Aquirre, C.
1985-01-01
Size distributions of air showers accompanied with bundle of high energy gamma rays and/or large size bursts under emulsion chambers, to study the composition of primary cosmic rays and also characteristics of high energy nuclear interaction. Air showers initiated by particles with a large cross section of interaction may develop from narrow region of the atmosphere near the top. Starting levels of air showers by particles with smaller cross section fluctuate in wider region of the atmosphere. Air showers of extremely small size accompanied with bundle of gamma rays may be ones initiated by protons at lower level after penetrating deep atmosphere without interaction. It is determined that the relative size distribution according to the total energy of bundle of gamma rays and the total burst size observed under 15 cm lead absorber.
Active MRI tracking for robotic assisted FUS
NASA Astrophysics Data System (ADS)
Xiao, Xu; Huang, Zhihong; Melzer, Andreas
2017-03-01
MR guided FUS is a noninvasive method producing thermal necrosis at the position of tumors with high accuracy and temperature control. Because the typical size of the ultrasound focus is smaller than the area of interested treatment tissues, focus repositioning become necessary to achieve multiple sonications to cover the whole targeted area. Using MR compatible mechanical actuators could help the ultrasound beam to reach a wider treatment range than using electrical beam steering technique and more flexibility in position the transducer. An active MR tracking technique was combined into the MRgFUS system to help locating the position of the mechanical actuator and the FUS transducer. For this study, a precise agar reference model was designed and fabricated to test the performance of the active tracking technique when it was used on the MR-compatible robotics InnoMotion™ (IBSMM, Engineering spol. s r.o. / Ltd, Czech Republic). The precision, tracking range and positioning speed of the combined robotic FUS system were evaluated in this study. Compared to the existing MR guided HIFU systems, the combined robotic system with active tracking techniques provides a potential that allows the FUS treatment to operate in a larger spatial range and with a faster speed, which is one of the main challenges for organ motion tracking.
Life and Operating Range Extension of the BPT-4000 Qualification Model Hall Thruster
NASA Technical Reports Server (NTRS)
Welander, Ben; Carpenter, Christian; deGrys, Kristi; Hofer, Richard R.; Randolph, Thomas M.; Manzella, David H.
2006-01-01
Following completion of the 5,600 hr qualification life test of the BPT-4000 4.5 kW Hall Thruster Propulsion System, NASA and Aerojet have undertaken efforts to extend the qualified operating range and lifetime of the thruster to support a wider range of NASA missions. The system was originally designed for orbit raising and stationkeeping applications on military and commercial geostationary satellites. As such, it was designed to operate over a range of power levels from 3 to 4.5 kW. Studies of robotic exploration applications have shown that the cost savings provided by utilizing commercial technology that can operate over a wider range of power levels provides significant mission benefits. The testing reported on here shows that the 4.5 kW thruster as designed has the capability to operate efficiently down to power levels as low as 1 kW. At the time of writing, the BPT-4000 qualification thruster and cathode have accumulated over 400 hr of operation between 1 to 2 kW with an additional 600 hr currently planned. The thruster has demonstrated no issues with longer duration operation at low power.
2015-01-01
Abstract There are four different stable climate states for pure water atmospheres, as might exist on so-called “waterworlds.” I map these as a function of solar constant for planets ranging in size from Mars-sized to 10 Earth-mass. The states are as follows: globally ice covered (Ts⪅245 K), cold and damp (270⪅Ts⪅290 K), hot and moist (350⪅Ts⪅550 K), and very hot and dry (Tsx2A86;900 K). No stable climate exists for 290⪅Ts ⪅350 K or 550⪅Ts⪅900 K. The union of hot moist and cold damp climates describes the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong nonlinearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surface, so more thermal radiation is emitted and more sunlight absorbed (the former dominates). The atmospheres of small planets expand more due to weaker gravity; the effective runaway greenhouse threshold is about 35 W m−2 higher for Mars, 10 W m−2 higher for Earth or Venus, but only a few W m−2 higher for a 10 Earth-mass planet. There is an underlying (expansion-neglected) trend of increasing runaway greenhouse threshold with planetary size (40 W m−2 higher for a 10 Earth-mass planet than for Mars). Summing these opposing trends means that Venus-sized (or slightly smaller) planets are most susceptible to a runaway greenhouse. The habitable zone for pure water atmospheres is very narrow, with an insolation range of 0.07 times the solar constant. A wider habitable zone requires background gas and greenhouse gas: N2 and CO2 on Earth, which are biologically controlled. Thus, habitability depends on inhabitance. Key Words: Habitable zone—Runaway greenhouse—Waterworld—Climate. Astrobiology 15, 362–370. PMID:25984919
Andrew M. Minnis; Amy Y. Rossman; Nathan M. Kleczewski; S. Luke. Flory
2012-01-01
Many species of Bipolaris are important pathogens of grasses. This new species was isolated from Microstegium vimineum, an invasive plant in the USA. The fungus causes disease on Microstegium, but it also infects a wider range of hosts.
Solid oxide fuel cell operable over wide temperature range
Baozhen, Li; Ruka, Roswell J.; Singhal, Subhash C.
2001-01-01
Solid oxide fuel cells having improved low-temperature operation are disclosed. In one embodiment, an interfacial layer of terbia-stabilized zirconia is located between the air electrode and electrolyte of the solid oxide fuel cell. The interfacial layer provides a barrier which controls interaction between the air electrode and electrolyte. The interfacial layer also reduces polarization loss through the reduction of the air electrode/electrolyte interfacial electrical resistance. In another embodiment, the solid oxide fuel cell comprises a scandia-stabilized zirconia electrolyte having high electrical conductivity. The scandia-stabilized zirconia electrolyte may be provided as a very thin layer in order to reduce resistance. The scandia-stabilized electrolyte is preferably used in combination with the terbia-stabilized interfacial layer. The solid oxide fuel cells are operable over wider temperature ranges and wider temperature gradients in comparison with conventional fuel cells.
Modeling and Simulation of Ceramic Arrays to Improve Ballaistic Performance
2013-11-01
2219 , 2000 Tile gap is found to increase the DoP as compared to One Tile tiles The next step will be run simulations on narrower and wider gap sizes...experiments described in reference - ARL-TR- 2219 , 2000 □ Tile gap is found to increase the DoP as compared to One Tile tiles □ The next step will be run...L| Al m ^ s\\cr V^ 1 v^ □ Smoothed-particle hydrodynamics (SPH) used for all parts □ SPH size = 0.40-mm, totaling 278k
High Concentration Standard Aerosol Generator.
1985-07-31
Noncommercial Components .. .. ........ A-1 B. Maintenance Instructions and material Properties of Purchased Components . .. .. .. ... . . . . . . B-1...tration (if a lower flow or a wider size distribution is acceptable and 2) precautions and suggestions for use of different aerosol materials . Additional...details of the system (including shop drawings, i4t lists of materials , and maintenance of commercially available components) are given in
Harvey E. Kennedy
1988-01-01
Larger size and higher percentages of plantable 1-0 and 2-0 green ash (Fraxinus pennsylvanica Marsh.) and Nuttall oak (Quercus nuttallii Palmer) seedlings were produced in the wider spacing-lower density plots. Greater numbers of plantable seedlings were produced in the higher density plots. Spacing significantly affected...
C.W. Woodall; C.E. Fiedler; R.E. McRoberts
2009-01-01
Forest ecosystems may be actively managed toward heterogeneous stand structures to provide both economic (e.g., wood production and carbon credits) and environmental benefits (e.g., invasive pest resistance). In order to facilitate wider adoption of possibly more sustainable forest stand structures, defining growth expectations among alternative management scenarios is...
Wide range stress intensity factor expressions for ASTM E 399 standard fracture toughness specimens
NASA Technical Reports Server (NTRS)
Srawley, J. E.
1976-01-01
For each of the two types of specimens, bend and compact, described previously for plane strain fracture toughness of materials, E 399, a polynominal expression is given for calculation of the stress intensity factor, K, from the applied force, P, and the specimen dimensions. It is explicitly stated, however, that these expressions should not be used outside the range of relative crack length, a/W, from 0.45 to 0.55. While this range is sufficient for the purpose of E 399, the same specimen types are often used for other purposes over a much wider range of a/W; for example, in the study of fatigue crack growth. Expressions are presented which are at least as accurate as those in E 399-74, and which cover much wider ranges of a/W: for the three-point bend specimen from 0 to 1; and for the compact specimen from 0.2 to 1. The range has to be restricted for the compact specimen because of the proximity of the loading pin holes to the crackline, which causes the stress intensity factor to be sensitive to small variations in dimensions when a/W is small. This is a penalty inherently associated with the compactness of the specimen.
Improved density discrimination using agfacontour film
NASA Technical Reports Server (NTRS)
Goodding, R. A.
1973-01-01
A technique was developed for obtaining tone separations from black and white photographic materials. Agfacontour film and photographic derivatives are utilized to improve the density discrimination and decrease the density range from 0.45 to 0.08 units. This increase in capability extends the usefulness of tone separations to a wider range of subject matter and problem areas.
Size-dependent impact of CNTs on dynamic properties of calmodulin.
Gao, Jian; Wang, Liming; Kang, Seung-gu; Zhao, Lina; Ji, Mingjuan; Chen, Chunying; Zhao, Yuliang; Zhou, Ruhong; Li, Jingyuan
2014-11-07
There are growing concerns about the biosafety of nanomaterials such as carbon nanotubes (CNTs) as their applications become more widespread. We report here a theoretical and experimental study of the binding of various sizes of CNTs [CNT (4,4), (5,5), (6,6) and (7,7)] to calmodulin (CaM) protein and, in particular, their impact on the Ca(2+)-dependent dynamic properties of CaM. Our simulations show that all the CNTs can plug into the hydrophobic binding pocket of Ca(2+)-bound CaM with binding affinities comparable with the native substrate M13 peptide. Even though CNT (4,4) shows a similar behavior to the M13 peptide in its dissociation from Ca(2+)-free CaM, wider CNTs still bind firmly to CaM, indicating a potential failure of Ca(2+) regulation. Such a size-dependent impact of CNTs on the dynamic properties of CaM is a result of the excessively strong hydrophobic interactions between the wider CNTs and CaM. These simulation results were confirmed by circular dichroism spectroscopy, which showed that the secondary structures of CaM become insensitive to Ca(2+) concentrations after the addition of CNTs. Our findings indicate that the cytotoxicity of nanoparticles to proteins arises not only from the inhibition of static protein structures (binding pockets), but also from impacts on their dynamic properties.
Gaeuman, David; Andrews, E.D.; Krause, Andreas; Smith, Wes
2009-01-01
Bed load samples from four locations in the Trinity River of northern California are analyzed to evaluate the performance of the Wilcock‐Crowe bed load transport equations for predicting fractional bed load transport rates. Bed surface particles become smaller and the fraction of sand on the bed increases with distance downstream from Lewiston Dam. The dimensionless reference shear stress for the mean bed particle size (τ*rm) is largest near the dam, but varies relatively little between the more downstream locations. The relation between τ*rm and the reference shear stresses for other size fractions is constant across all locations. Total bed load transport rates predicted with the Wilcock‐Crowe equations are within a factor of 2 of sampled transport rates for 68% of all samples. The Wilcock‐Crowe equations nonetheless consistently under‐predict the transport of particles larger than 128 mm, frequently by more than an order of magnitude. Accurate prediction of the transport rates of the largest particles is important for models in which the evolution of the surface grain size distribution determines subsequent bed load transport rates. Values of τ*rm estimated from bed load samples are up to 50% larger than those predicted with the Wilcock‐Crowe equations, and sampled bed load transport approximates equal mobility across a wider range of grain sizes than is implied by the equations. Modifications to the Wilcock‐Crowe equation for determining τ*rm and the hiding function used to scale τ*rm to other grain size fractions are proposed to achieve the best fit to observed bed load transport in the Trinity River.
Anazawa, Takashi; Yamazaki, Motohiro
2017-12-05
Although multi-point, multi-color fluorescence-detection systems are widely used in various sciences, they would find wider applications if they are miniaturized. Accordingly, an ultra-small, four-emission-point and four-color fluorescence-detection system was developed. Its size (space between emission points and a detection plane) is 15 × 10 × 12 mm, which is three-orders-of-magnitude smaller than that of a conventional system. Fluorescence from four emission points with an interval of 1 mm on the same plane was respectively collimated by four lenses and split into four color fluxes by four dichroic mirrors. Then, a total of sixteen parallel color fluxes were directly input into an image sensor and simultaneously detected. The emission-point plane and the detection plane (the image-sensor surface) were parallel and separated by a distance of only 12 mm. The developed system was applied to four-capillary array electrophoresis and successfully achieved Sanger DNA sequencing. Moreover, compared with a conventional system, the developed system had equivalent high fluorescence-detection sensitivity (lower detection limit of 17 pM dROX) and 1.6-orders-of-magnitude higher dynamic range (4.3 orders of magnitude).
Physical characteristics and resistance parameters of typical urban cyclists.
Tengattini, Simone; Bigazzi, Alexander York
2018-03-30
This study investigates the rolling and drag resistance parameters and bicycle and cargo masses of typical urban cyclists. These factors are important for modelling of cyclist speed, power and energy expenditure, with applications including exercise performance, health and safety assessments and transportation network analysis. However, representative values for diverse urban travellers have not been established. Resistance parameters were measured utilizing a field coast-down test for 557 intercepted cyclists in Vancouver, Canada. Masses were also measured, along with other bicycle attributes such as tire pressure and size. The average (standard deviation) of coefficient of rolling resistance, effective frontal area, bicycle plus cargo mass, and bicycle-only mass were 0.0077 (0.0036), 0.559 (0.170) m 2 , 18.3 (4.1) kg, and 13.7 (3.3) kg, respectively. The range of measured values is wider and higher than suggested in existing literature, which focusses on sport cyclists. Significant correlations are identified between resistance parameters and rider and bicycle attributes, indicating higher resistance parameters for less sport-oriented cyclists. The findings of this study are important for appropriately characterising the full range of urban cyclists, including commuters and casual riders.
Robotic active positioning for magnetic resonance-guided high-intensity focused ultrasound
NASA Astrophysics Data System (ADS)
Xiao, Xu; Huang, Zhihong; Volovick, Alexander; Melzer, Andreas
2012-11-01
Magnetic resonance (MR) guided High-intensity focused ultrasound (HIFU) is a noninvasive method producing thermal necrosis and cavitation at the position of tumors with high accuracy. Because the typical size of the high-intensity focused ultrasound focus are much smaller than the targeted tumor or other tissues, multiple sonications and focus repositioning become necessary for HIFU treatment. In order to reach a much wider range, manual repositioning or using MR compatible mechanical actuators could be used. The repositioning technique is a time consuming procedure because it needs a series of MR imaging to detect the transducer and markers preplaced on the mechanical devices. We combined an active tracking technique into the MR guided HIFU system. In this work, the robotic system used is the MR-compatible robotics from InnoMotion{trade mark, serif} (IBSMM, Engineering spol. s r.o. / Ltd, Czech) which is originally designed for MR-guided needle biopsy. The precision and positioning speed of the combined robotic HIFU system are evaluated in this study. Compared to the existing MR guided HIFU systems, the combined robotic system with active tracking techniques provides a potential that allows the HIFU treatment to operate in a larger spatial range and with a faster speed.
Equation of State and Electrical Conductivity of Helium at High Pressures and Temperatures
NASA Astrophysics Data System (ADS)
McWilliams, R. S.; Eggert, J. H.; Loubeyre, P.; Brygoo, S.; Collins, G.; Jeanloz, R.
2004-12-01
Helium, the second-most abundant element in the universe and giant planets, is expected to metallize at much higher pressures and temperatures than the most abundant element, hydrogen. The difference in chemical-bonding character, between insulator and metal, is expected to make hydrogen-helium mixtures immiscible throughout large fractions of planetary interiors, and therefore subject to gravitational separation contributing significantly to the internal dynamics of giant planets. Using laser-driven shock waves on samples pre-compressed in high-pressure cells, we have obtained the first measurements of optical reflectivity from the shock front in helium to pressures of 146 GPa. The reflectivity exceeds 5% above \\ensuremath{\\sim} 100 GPa, indicating high electrical conductivity. By varying the initial pressure (hence density) of the sample, we can access a much wider range of final pressure-temperature conditions than is possible in conventional Hugoniot experiments. Our work increases by nine-fold the pressure range of single-shock measurements, in comparison with gas-gun experiments, and yields results in agreement with the Saumon, Chabrier and Van Horn (1994) equation of state for helium. This changes the internal structures inferred for Jupiter-size planets, relative to models based on earlier equations of state (e. g., SESAME).
Prediction of Airfoil Characteristics With Higher Order Turbulence Models
NASA Technical Reports Server (NTRS)
Gatski, Thomas B.
1996-01-01
This study focuses on the prediction of airfoil characteristics, including lift and drag over a range of Reynolds numbers. Two different turbulence models, which represent two different types of models, are tested. The first is a standard isotropic eddy-viscosity two-equation model, and the second is an explicit algebraic stress model (EASM). The turbulent flow field over a general-aviation airfoil (GA(W)-2) at three Reynolds numbers is studied. At each Reynolds number, predicted lift and drag values at different angles of attack are compared with experimental results, and predicted variations of stall locations with Reynolds number are compared with experimental data. Finally, the size of the separation zone predicted by each model is analyzed, and correlated with the behavior of the lift coefficient near stall. In summary, the EASM model is able to predict the lift and drag coefficients over a wider range of angles of attack than the two-equation model for the three Reynolds numbers studied. However, both models are unable to predict the correct lift and drag behavior near the stall angle, and for the lowest Reynolds number case, the two-equation model did not predict separation on the airfoil near stall.
Laboratory Simulations on Haze Formation in Cool Exoplanet Atmospheres
NASA Astrophysics Data System (ADS)
He, Chao; Horst, Sarah; Lewis, Nikole; Yu, Xinting; McGuiggan, Patricia; Moses, Julianne I.
2017-10-01
The Kepler mission has shown that the most abundant types of planets are super-Earths and mini-Neptunes among ~3500 confirmed exoplanets, and these types of exoplanets are expected to exhibit a wide variety of atmospheric compositions. Recent transit spectra have demonstrated that clouds and/or hazes could play a significant role in these planetary atmospheres (Deming et al. 2013, Knutson et al. 2014, Kreidberg et al. 2014, Pont, et al. 2013). However, very little laboratory work has been done to understand the formation of haze over a broad range of atmospheric compositions. Here we conducted a series of laboratory simulations to investigate haze formation in a range of planetary atmospheres using our newly built Planetary HAZE Research (PHAZER) chamber (He et al. 2017). We ran experimental simulations for nine different atmospheres: three temperatures (300 K, 400 K, and 600 K) and three metallicities (100, 1000, and 10000 times solar metallicity) using AC glow discharge as an energy source to irradiate gas mixtures. We found that haze particles are formed in all nine experiments, but the haze production rates are dramatically different for different cases. We investigated the particle sizes of the haze particles deposited on quartz discs using atomic force microscopy (AFM). The AFM images show that the particle size varies from 30 nm to 200 nm. The haze particles are more uniform for 100x solar metallicity experiments (30 nm to 40 nm) while the particles sizes for 1000x and 10000x solar metallicity experiments have wider distributions (30 nm to 200 nm). The particle size affects the scattering of light, and thus the temperature structure of planetary atmospheres. The haze production rates and particle size distributions obtained here can serve as critical inputs to atmospheric physical and chemical tools to understand the exoplanetary atmospheres and help guide future TESS and JWST observations of super-Earths and mini-Neptunes.Ref:Deming, D., et al. 2013, ApJ, 774, 95.He, C., et al. 2017, APJL, 841, L31.Knutson, H. A., et al. 2014, Nat. 505, 66.Kreidberg, L., et al. 2014, Nat. 505, 69.Pont, F., et al. 2013, MNRAS, 432, 2917.
A comparison study of size-specific dose estimate calculation methods.
Parikh, Roshni A; Wien, Michael A; Novak, Ronald D; Jordan, David W; Klahr, Paul; Soriano, Stephanie; Ciancibello, Leslie; Berlin, Sheila C
2018-01-01
The size-specific dose estimate (SSDE) has emerged as an improved metric for use by medical physicists and radiologists for estimating individual patient dose. Several methods of calculating SSDE have been described, ranging from patient thickness or attenuation-based (automated and manual) measurements to weight-based techniques. To compare the accuracy of thickness vs. weight measurement of body size to allow for the calculation of the size-specific dose estimate (SSDE) in pediatric body CT. We retrospectively identified 109 pediatric body CT examinations for SSDE calculation. We examined two automated methods measuring a series of level-specific diameters of the patient's body: method A used the effective diameter and method B used the water-equivalent diameter. Two manual methods measured patient diameter at two predetermined levels: the superior endplate of L2, where body width is typically most thin, and the superior femoral head or iliac crest (for scans that did not include the pelvis), where body width is typically most thick; method C averaged lateral measurements at these two levels from the CT projection scan, and method D averaged lateral and anteroposterior measurements at the same two levels from the axial CT images. Finally, we used body weight to characterize patient size, method E, and compared this with the various other measurement methods. Methods were compared across the entire population as well as by subgroup based on body width. Concordance correlation (ρ c ) between each of the SSDE calculation methods (methods A-E) was greater than 0.92 across the entire population, although the range was wider when analyzed by subgroup (0.42-0.99). When we compared each SSDE measurement method with CTDI vol, there was poor correlation, ρ c <0.77, with percentage differences between 20.8% and 51.0%. Automated computer algorithms are accurate and efficient in the calculation of SSDE. Manual methods based on patient thickness provide acceptable dose estimates for pediatric patients <30 cm in body width. Body weight provides a quick and practical method to identify conversion factors that can be used to estimate SSDE with reasonable accuracy in pediatric patients with body width ≥20 cm.
Asymmetry of projected increases in extreme temperature distributions
Kodra, Evan; Ganguly, Auroop R.
2014-01-01
A statistical analysis reveals projections of consistently larger increases in the highest percentiles of summer and winter temperature maxima and minima versus the respective lowest percentiles, resulting in a wider range of temperature extremes in the future. These asymmetric changes in tail distributions of temperature appear robust when explored through 14 CMIP5 climate models and three reanalysis datasets. Asymmetry of projected increases in temperature extremes generalizes widely. Magnitude of the projected asymmetry depends significantly on region, season, land-ocean contrast, and climate model variability as well as whether the extremes of consideration are seasonal minima or maxima events. An assessment of potential physical mechanisms provides support for asymmetric tail increases and hence wider temperature extremes ranges, especially for northern winter extremes. These results offer statistically grounded perspectives on projected changes in the IPCC-recommended extremes indices relevant for impacts and adaptation studies. PMID:25073751
A compact CCD-monitored atomic force microscope with optical vision and improved performances.
Mingyue, Liu; Haijun, Zhang; Dongxian, Zhang
2013-09-01
A novel CCD-monitored atomic force microscope (AFM) with optical vision and improved performances has been developed. Compact optical paths are specifically devised for both tip-sample microscopic monitoring and cantilever's deflection detecting with minimized volume and optimal light-amplifying ratio. The ingeniously designed AFM probe with such optical paths enables quick and safe tip-sample approaching, convenient and effective tip-sample positioning, and high quality image scanning. An image stitching method is also developed to build a wider-range AFM image under monitoring. Experiments show that this AFM system can offer real-time optical vision for tip-sample monitoring with wide visual field and/or high lateral optical resolution by simply switching the objective; meanwhile, it has the elegant performances of nanometer resolution, high stability, and high scan speed. Furthermore, it is capable of conducting wider-range image measurement while keeping nanometer resolution. Copyright © 2013 Wiley Periodicals, Inc.
Anna Schoettle; S. G. Rochelle
2000-01-01
Limber pine (Pinus flexilis James) grows across a wider range of elevations than any other tree species in the central Rockies, from ;1600 m at Pawnee Buttes to .3300 m at Rollins Pass. In this study we investigated two possible explanations for limber pineâs success across a broad range of elevations: (1) the sites on which it is found, although separated by...
Gallagher, R V; Randall, R P; Leishman, M R
2015-04-01
The ability to predict which alien plants will transition from naturalized to invasive prior to their introduction to novel regions is a key goal for conservation and has the potential to increase the efficacy of weed risk assessment (WRA). However, multiple factors contribute to plant invasion success (e.g., functional traits, range characteristics, residence time, phylogeny), and they all must be taken into account simultaneously in order to identify meaningful correlates of invasion success. We compiled 146 pairs of phylogenetically paired (congeneric) naturalized and invasive plant species in Australia with similar minimum residence times (i.e., time since introduction in years). These pairs were used to test for differences in 5 functional traits (flowering duration, leaf size, maximum height, specific leaf area [SLA], seed mass) and 3 characteristics of species' native ranges (biome occupancy, mean annual temperature, and rainfall breadth) between naturalized and invasive species. Invasive species, on average, had larger SLA, longer flowering periods, and were taller than their congeneric naturalized relatives. Invaders also exhibited greater tolerance for different environmental conditions in the native range, where they occupied more biomes and a wider breadth of rainfall and temperature conditions than naturalized congeners. However, neither seed mass nor leaf size differed between pairs of naturalized and invasive species. A key finding was the role of SLA in distinguishing between naturalized and invasive pairs. Species with high SLA values were typically associated with faster growth rates, more rapid turnover of leaf material, and shorter lifespans than those species with low SLA. This suite of characteristics may contribute to the ability of a species to transition from naturalized to invasive across a wide range of environmental contexts and disturbance regimes. Our findings will help in the refinement of WRA protocols, and we advocate the inclusion of quantitative traits, in particular SLA, into the WRA schemes. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.
Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain; Aeschimann, David; Dullinger, Stefan; Gégout, Jean-Claude; Guisan, Antoine; Pauli, Harald; Renaud, Julien; Theurillat, Jean-Paul; Thuiller, Wilfried; Van Es, Jérémie; Vittoz, Pascal; Willner, Wolfgang; Wohlgemuth, Thomas; Zimmermann, Niklaus E.; Svenning, Jens-Christian
2015-01-01
The role of competition for light among plants has long been recognised at local scales, but its importance for plant species distributions at larger spatial scales has generally been ignored. Tree cover modifies the local abiotic conditions below the canopy, notably by reducing light availability, and thus, also the performance of species that are not adapted to low-light conditions. However, this local effect may propagate to coarser spatial grains, by affecting colonisation probabilities and local extinction risks of herbs and shrubs. To assess the effect of tree cover at both the plot- and landscape-grain sizes (approximately 10-m and 1-km), we fit Generalised Linear Models (GLMs) for the plot-level distributions of 960 species of herbs and shrubs using 6,935 vegetation plots across the European Alps. We ran four models with different combinations of variables (climate, soil and tree cover) at both spatial grains for each species. We used partial regressions to evaluate the independent effects of plot- and landscape-grain tree cover on plot-level plant communities. Finally, the effects on species-specific elevational range limits were assessed by simulating a removal experiment comparing the species distributions under high and low tree cover. Accounting for tree cover improved the model performance, with the probability of the presence of shade-tolerant species increasing with increasing tree cover, whereas shade-intolerant species showed the opposite pattern. The tree cover effect occurred consistently at both the plot and landscape spatial grains, albeit most strongly at the former. Importantly, tree cover at the two grain sizes had partially independent effects on plot-level plant communities. With high tree cover, shade-intolerant species exhibited narrower elevational ranges than with low tree cover whereas shade-tolerant species showed wider elevational ranges at both limits. These findings suggest that forecasts of climate-related range shifts for herb and shrub species may be modified by tree cover dynamics. PMID:26290621
Soliven, Arianne; Haidar Ahmad, Imad A; Tam, James; Kadrichu, Nani; Challoner, Pete; Markovich, Robert; Blasko, Andrei
2017-09-05
Amikacin, an aminoglycoside antibiotic lacking a UV chromophore, was developed into a drug product for delivery by inhalation. A robust method for amikacin assay analysis and aerosol particle size distribution (aPSD) determination, with comparable performance to the conventional UV detector was developed using a charged aerosol detector (CAD). The CAD approach involved more parameters for optimization than UV detection due to its sensitivity to trace impurities, non-linear response and narrow dynamic range of signal versus concentration. Through careful selection of the power transformation function value and evaporation temperature, a wider linear dynamic range, improved signal-to-noise ratio and high repeatability were obtained. The influences of mobile phase grade and glassware binding of amikacin during sample preparation were addressed. A weighed (1/X 2 ) least square regression was used for the calibration curve. The limit of quantitation (LOQ) and limit of detection (LOD) for this method were determined to be 5μg/mL and 2μg/mL, respectively. The method was validated over a concentration range of 0.05-2mg/mL. The correlation coefficient for the peak area versus concentration was 1.00 and the y-intercept was 0.2%. The recovery accuracies of triplicate preparations at 0.05, 1.0, and 2.0mg/mL were in the range of 100-101%. The relative standard deviation (S rel ) of six replicates at 1.0mg/mL was 1%, and S rel of five injections at the limit of quantitation was 4%. A robust HPLC-CAD method was developed and validated for the determination of the aPSD for amikacin. The CAD method development produced a simplified procedure with minimal variability in results during: routine operation, transfer from one instrument to another, and between different analysts. Copyright © 2017 Elsevier B.V. All rights reserved.
Wine glass size and wine sales: a replication study in two bars.
Pechey, Rachel; Couturier, Dominique-Laurent; Hollands, Gareth J; Mantzari, Eleni; Zupan, Zorana; Marteau, Theresa M
2017-08-01
Wine glass size may influence perceived volume and subsequently purchasing and consumption. Using a larger glass to serve the same portions of wine was found to increase wine sales by 9.4% (95% CI 1.9, 17.5) in a recent study conducted in one bar. The current study aimed to replicate this previous work in two other bars using a wider range of glass sizes. To match the previous study, a repeated multiple treatment reversal design, during which wine was served in glasses of the same design but different sizes, was used. The study was conducted in two bars in Cambridge, England, using glass sizes of 300, 370, 510 ml (Bar 1) and 300 and 510 ml (Bar 2). Customers purchased their choice of a 750 ml bottle, or standard UK measures of 125, 175 or 250 ml of wine, each of which was served with the same glass. Bar 1 Daily wine volume (ml) purchased was 10.5% (95% CI 1.0, 20.9) higher when sold in 510 ml compared to 370 ml glasses; but sales were not significantly higher with 370 ml versus 300 ml glasses (6.5%, 95% CI -5.2, 19.6). Bar 2 Findings were inconclusive as to whether daily wine purchased differed when using 510 ml versus 300 ml glasses (-1.1%, 95% CI -12.6, 11.9). These results provide a partial replication of previous work showing that introducing larger glasses (without manipulating portion size) increases purchasing. Understanding the mechanisms by which wine glass size influences consumption may elucidate when the effect can be expected and when not. Trial registration This study is a replication study, based on the procedure set out in the trial registration for the study that it attempts to replicate (ISRCTN registry: ISRCTN12018175).
Forrester, David I
2015-03-01
Mixtures can be more productive than monocultures and may therefore use more water, which may make them more susceptible to droughts. The species interactions that influence growth, transpiration and water-use efficiency (WUE, tree growth per unit transpiration) within a given mixture vary with intra- and inter-annual climatic variability, stand density and tree size, but these effects remain poorly quantified. These relationships were examined in mixtures and monocultures of Eucalyptus globulus Labill. and Acacia mearnsii de Wildeman. Growth and transpiration were measured between ages 14 and 15 years. All E. globulus trees in mixture that were growing faster than similar sized trees in monocultures had higher WUE, while trees with similar growth rates had similar WUE. By the age of 14 years A. mearnsii trees were beginning to senesce and there were no longer any relationships between tree size and growth or WUE. The relationship between transpiration and tree size did not differ between treatments for either species, so stand-level increases in transpiration simply reflected the larger mean tree size in mixtures. Increasing neighbourhood basal area increased the complementarity effect on E. globulus growth and transpiration. The complementarity effect also varied throughout the year, but this was not related to the climatic seasonality. This study shows that stand-level responses can be the net effect of a much wider range of individual tree-level responses, but at both levels, if growth has not increased for a given species, it appears unlikely that there will be differences in transpiration or WUE for that species. Growth data may provide a useful initial indication of whether mixtures have higher transpiration or WUE, and which species and tree sizes contribute to this effect. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Update on Emergency Department Visits Involving Energy Drinks: A Continuing Public Health Concern
... concentrated forms of energy drinks, known as energy shots, have become increasingly popular among a wider range ... 3 Marketing analysts reported increasing sales of energy shots in 2011 that were expected to continue through ...
NASA Astrophysics Data System (ADS)
Barazzetti, L.; Banfi, F.; Brumana, R.; Oreni, D.; Previtali, M.; Roncoroni, F.
2015-08-01
This paper describes a procedure for the generation of a detailed HBIM which is then turned into a model for mobile apps based on augmented and virtual reality. Starting from laser point clouds, photogrammetric data and additional information, a geometric reconstruction with a high level of detail can be carried out by considering the basic requirements of BIM projects (parametric modelling, object relations, attributes). The work aims at demonstrating that a complex HBIM can be managed in portable devices to extract useful information not only for expert operators, but also towards a wider user community interested in cultural tourism.
Glavičić, Snježana; Anić, Ivica; Braut, Alen; Miletić, Ivana; Borčić, Josipa
2011-08-01
The purpose was to measure and analyse the vertical force and torque developed in the wider and narrower root canals during hand ProTaper instrumentation. Twenty human incisors were divided in two groups. Upper incisors were experimental model for the wide, while the lower incisors for the narrow root canals. Measurements of the force and torque were done by a device constructed for this purpose. Differences between the groups were statistically analysed by Mann-Whitney U-test with the significance level set to P<0.05. Vertical force in the upper incisors ranged 0.25-2.58 N, while in the lower incisors 0.38-6.94 N. Measured torque in the upper incisors ranged 0.53-12.03 Nmm, while in the lower incisor ranged 0.94-10.0 Nmm. Vertical force and torque were higher in the root canals of smaller diameter. The increase in the contact surface results in increase of the vertical force and torque as well in both narrower and wider root canals. © 2010 The Authors. Australian Endodontic Journal © 2010 Australian Society of Endodontology.
Molecular evidence for species-level distinctions in clouded leopards.
Buckley-Beason, Valerie A; Johnson, Warren E; Nash, Willliam G; Stanyon, Roscoe; Menninger, Joan C; Driscoll, Carlos A; Howard, JoGayle; Bush, Mitch; Page, John E; Roelke, Melody E; Stone, Gary; Martelli, Paolo P; Wen, Ci; Ling, Lin; Duraisingam, Ratna K; Lam, Phan V; O'Brien, Stephen J
2006-12-05
Among the 37 living species of Felidae, the clouded leopard (Neofelis nebulosa) is generally classified as a monotypic genus basal to the Panthera lineage of great cats. This secretive, mid-sized (16-23 kg) carnivore, now severely endangered, is traditionally subdivided into four southeast Asian subspecies (Figure 1A). We used molecular genetic methods to re-evaluate subspecies partitions and to quantify patterns of population genetic variation among 109 clouded leopards of known geographic origin (Figure 1A, Tables S1 ans S2 in the Supplemental Data available online). We found strong phylogeographic monophyly and large genetic distances between N. n. nebulosa (mainland) and N. n. diardi (Borneo; n = 3 individuals) with mtDNA (771 bp), nuclear DNA (3100 bp), and 51 microsatellite loci. Thirty-six fixed mitochondrial and nuclear nucleotide differences and 20 microsatellite loci with nonoverlapping allele-size ranges distinguished N. n. nebulosa from N. n. diardi. Along with fixed subspecies-specific chromosomal differences, this degree of differentiation is equivalent to, or greater than, comparable measures among five recognized Panthera species (lion, tiger, leopard, jaguar, and snow leopard). These distinctions increase the urgency of clouded leopard conservation efforts, and if affirmed by morphological analysis and wider sampling of N. n. diardi in Borneo and Sumatra, would support reclassification of N. n. diardi as a new species (Neofelis diardi).
Osunkoya, Olusegun O; Omar-Ali, Kharunnisa; Amit, Norratna; Dayan, Juita; Daud, Dayanawati S; Sheng, Tan K
2007-12-01
In rainforests, trunk size, strength, crown position, and geometry of a tree affect light interception and the likelihood of mechanical failure. Allometric relationships of tree diameter, wood density, and crown architecture vs. height are described for a diverse range of rainforest trees in Brunei, northern Borneo. The understory species follow a geometric model in their diameter-height relationship (slope, β = 1.08), while the stress-elasticity models prevail (β = 1.27-1.61) for the midcanopy and canopy/emergent species. These relationships changed with ontogeny, especially for the understory species. Within species, the tree stability safety factor (SSF) and relative crown width decreased exponentially with increasing tree height. These trends failed to emerge in across-species comparisons and were reversed at a common (low) height. Across species, the relative crown depth decreased with maximum potential height and was indistinguishable at a common (low) height. Crown architectural traits influence SSF more than structural property of wood density. These findings emphasize the importance of applying a common reference size in comparative studies and suggest that forest trees (especially the understory group) may adapt to low light by having deeper rather than wider crowns due to an efficient distribution and geometry of their foliage.
NASA Astrophysics Data System (ADS)
Wang, Y.; Bradford, S. A.; Simunek, J.
2011-12-01
Laboratory and numerical studies were conducted to investigate the influence of physical and chemical factors on the transport of E.coli O157:H7 and coliphage φX174 through preferential flow systems. Preferential flow systems were created in 13.2 cm diameter and 20 cm length columns by embedding sand lens of various grain size, length, and vertical position into finer textured matrix sand. Tracer solutions containing bromide and microbes were prepared at different ionic strength (IS) and sprayed onto the surface of the columns at desired steady rates using a rain simulator to achieve saturated or unsaturated conditions. Effluents were collected at the column bottom continuously and analyzed for concentrations of bromide, φX174, and E.coli. Complementary numerical simulations were conducted using the HYDRUS 2D code over a wider range of physical and chemical conditions, and to analyze bromide and microbe transport in the columns. Results indicated that preferential transport of the microbes was dependent on the hydraulic contrasts between the matrix and lens, the length of the lens, the size of microorganism, and the water saturation. The IS also influenced the preferential transport of microbes. In particular, increasing retention with IS decreased the overall microbe transport but increased the relative importance of preferential flow.
Various supercritical carbon dioxide cycle layouts study for molten carbonate fuel cell application
NASA Astrophysics Data System (ADS)
Bae, Seong Jun; Ahn, Yoonhan; Lee, Jekyoung; Lee, Jeong Ik
2014-12-01
Various supercritical carbon dioxide (S-CO2) cycles for a power conversion system of a Molten Carbonate Fuel Cell (MCFC) hybrid system are studied in this paper. Re-Compressing Brayton (RCB) cycle, Simple Recuperated Brayton (SRB) cycle and Simple Recuperated Transcritical (SRT) cycle layouts were selected as candidates for this study. In addition, a novel concept of S-CO2 cycle which combines Brayton cycle and Rankine cycle is proposed and intensively studied with other S-CO2 layouts. A parametric study is performed to optimize the total system to be compact and to achieve wider operating range. Performances of each S-CO2 cycle are compared in terms of the thermal efficiency, net electricity of the MCFC hybrid system and approximate total volumes of each S-CO2 cycle. As a result, performance and total physical size of S-CO2 cycle can be better understood for MCFC S-CO2 hybrid system and especially, newly suggested S-CO2 cycle shows some success.
The role of the pathologist in wound management.
Lansdown, Alan B G
Skin wounds result from a wide variety of physical insults, traumas and idiopathic causes. All are prone to infection and vulnerable to dehydration, contamination and further damage from environmental insult. Appropriate therapy depends upon correct diagnosis of the lesion, wound bed preparation with antimicrobial measures as required, and selection and application of suitable dressings. Whereas tissue viability clinicians and nurses will routinely assess levels of tissue damage and infection through observation of the colour, depth and size of wounds, backed up by microbiological assessment, a range of laboratory pathological services are available to give a wider picture of clinical wounds and possible causes of indolence and non-healing. This review identifies the contribution that specialist pathologists can make to identifying immunological changes in patients and toxic events resulting from the use of xenobiotic materials in wound management, and unravelling the mechanistic action of wound care products. Emphasis is placed on the central role of research in furthering the study of wound healing and mechanisms of chronicity.
Luo, Jie; Huang, Ziyu; Liu, Hongna; Zhang, Yan; Ren, Fazheng
2018-04-15
Yak milk fat products constitute the base of Qinghai-Tibetan pastoralists' daily food intake. Despite the great importance of fat in processing and pastoralists' health, studies about yak milk fat are scarce. In this study, the lipid composition and the morphological properties of milk fat globule membranes (MFGMs) of yak milk were investigated. The results demonstrated that the yak milk had a higher cholesterol and sphingomyelin content compared to cow milk. In situ structural investigations performed at 25 °C by confocal microscopy showed the presence of lipid domains in yak MFGM, with a larger number and wider size range compared to cow milk. Moreover, the simultaneous localization of glycosylated molecules and polar lipids indicated that glycosylated molecules could be integrated into the lipid domains in yak MFGM. Different characteristics in yak MFGM could be related to the lipid composition and may affect the functions of yak milk lipids during processing and digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.
Corvari, Vincent; Narhi, Linda O; Spitznagel, Thomas M; Afonina, Nataliya; Cao, Shawn; Cash, Patricia; Cecchini, Irene; DeFelippis, Michael R; Garidel, Patrick; Herre, Andrea; Koulov, Atanas V; Lubiniecki, Tony; Mahler, Hanns-Christian; Mangiagalli, Paolo; Nesta, Douglas; Perez-Ramirez, Bernardo; Polozova, Alla; Rossi, Mara; Schmidt, Roland; Simler, Robert; Singh, Satish; Weiskopf, Andrew; Wuchner, Klaus
2015-11-01
Measurement and characterization of subvisible particles (including proteinaceous and non-proteinaceous particulate matter) is an important aspect of the pharmaceutical development process for biotherapeutics. Health authorities have increased expectations for subvisible particle data beyond criteria specified in the pharmacopeia and covering a wider size range. In addition, subvisible particle data is being requested for samples exposed to various stress conditions and to support process/product changes. Consequently, subvisible particle analysis has expanded beyond routine testing of finished dosage forms using traditional compendial methods. Over the past decade, advances have been made in the detection and understanding of subvisible particle formation. This article presents industry case studies to illustrate the implementation of strategies for subvisible particle analysis as a characterization tool to assess the nature of the particulate matter and applications in drug product development, stability studies and post-marketing changes. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.
Coatings of black carbon in Tijuana, Mexico, during the CalMex Campaign
NASA Astrophysics Data System (ADS)
Takahama, S.; Russell, L. M.; Duran, R.; Subramanian, R.; Kok, G.
2010-12-01
Black carbon number and mass concentrations were measured by a single-particle soot photometer (SP2; by Droplet Measurement Technologies) in Tijuana, Mexico between May 15, 2010, and June 30, 2010, for the CalMex campaign. The measurement site, Parque Morelos, is a recreational area located in the Southeast region of Tijuana. The SP2 was equipped with 8-channels of signal detection that spans a wider range of sensitivity for incandescing and scattering measurements than traditional configurations. The campaign-average number concentration of incandescing particles was 280 #/cc, peaking during traffic activity in the mornings. Incandescing particles made up 50% of all particles (incandescing and purely scattering) detected by the SP2. The mode of the number size distribution estimated for black carbon, according to estimated mass-equivalent diameters, was approximately 100 nm or smaller. Temporal variations in estimated coating thicknesses for these black carbon particles are discussed together with co-located measurements of organic aerosol and inorganic salts.
Cortical and diencephalic lesions in Korsakoff's syndrome: a clinical and CT scan study.
Jacobson, R R; Lishman, W A
1990-02-01
Twenty-five male alcoholic Korsakoff patients were compared with age and sex-matched non-Korsakoff chronic alcoholics and healthy volunteers on clinical and CT brain scan parameters. The scans were assessed by planimetry, visual grading procedures and computerized analysis. Reliable measures of third ventricular size were developed. The Korsakoff patients had wider third ventricles, larger lateral ventricles and wider interhemispheric fissures than the comparison groups; but sulcal and Sylvian fissure widths were equivalent in Korsakoff and non-Korsakoff alcoholics. The results suggest that, in addition to their well-established diencephalic lesions, many Korsakoff patients have sustained widespread cerebral damage. Shrinkage in the frontal brain regions appears to be especially pronounced. The implications for a dual aetiology of alcoholic Korsakoff's syndrome involving thiamine deficiency and features associated with alcoholism, probably direct alcohol neurotoxicity, are discussed.
Dunbar's number: group size and brain physiology in humans reexamined.
de Ruiter, Jan; Weston, Gavin; Lyon, Stephen M
2011-01-01
Popular academic ideas linking physiological adaptations to social behaviors are spreading disconcertingly into wider societal contexts. In this article, we note our skepticism with one particularly popular—in our view, problematic—supposed causal correlation between neocortex size and social group size. The resulting Dunbar's Number, as it has come to be called, has been statistically tested against observed group size in different primate species. Although there may be reason to doubt the Dunbar's Number hypothesis among nonhuman primate species, we restrict ourselves here to the application of such an explanatory hypothesis to human, culture-manipulating populations. Human information process management, we argue, cannot be understood as a simple product of brain physiology. Cross-cultural comparison of not only group size but also relationship-reckoning systems like kinship terminologies suggests that although neocortices are undoubtedly crucial to human behavior, they cannot be given such primacy in explaining complex group composition, formation, or management.
Freeman, B M; Chaves-Campos, J
2016-06-01
Fallen branches are often incorporated into Atta cephalotes (L.) foraging trails to optimize leaf tissue transport rates and economize trail maintenance. Recent studies in lowlands show laden A. cephalotes travel faster across fallen branches than on ground, but more slowly ascending or descending a branch. The latter is likely because (1) it is difficult to travel up or downhill and (2) bottlenecks occur when branches are narrower than preceding trail. Hence, both branch height and width should determine whether branches decrease net travel times, but no study has evaluated it yet. Laden A. cephalotes were timed in relation to branch width and height across segments preceding, accessing, across, and departing a fallen branch in the highlands of Costa Rica. Ants traveled faster on branches than on cleared segments of trunk-trail, but accelerated when ascending or descending the branch-likely because of the absence of bottlenecks during the day in the highlands. Branch size did not affect ant speed in observed branches; the majority of which (22/24) varied from 11 to 120 mm in both height and width (average 66 mm in both cases). To determine whether ants exclude branches outside this range, ants were offered the choice between branches within this range and branches that were taller/wider than 120 mm. Ants strongly preferred the former. Our results indicate that A. cephalotes can adjust their speed to compensate for the difficulty of traveling on branch slopes. More generally, branch size should be considered when studying ant foraging efficiency.
Planetary and Space Simulation Facilities PSI at DLR for Astrobiology
NASA Astrophysics Data System (ADS)
Rabbow, E.; Rettberg, P.; Panitz, C.; Reitz, G.
2008-09-01
Ground based experiments, conducted in the controlled planetary and space environment simulation facilities PSI at DLR, are used to investigate astrobiological questions and to complement the corresponding experiments in LEO, for example on free flying satellites or on space exposure platforms on the ISS. In-orbit exposure facilities can only accommodate a limited number of experiments for exposure to space parameters like high vacuum, intense radiation of galactic and solar origin and microgravity, sometimes also technically adapted to simulate extraterrestrial planetary conditions like those on Mars. Ground based experiments in carefully equipped and monitored simulation facilities allow the investigation of the effects of simulated single environmental parameters and selected combinations on a much wider variety of samples. In PSI at DLR, international science consortia performed astrobiological investigations and space experiment preparations, exposing organic compounds and a wide range of microorganisms, reaching from bacterial spores to complex microbial communities, lichens and even animals like tardigrades to simulated planetary or space environment parameters in pursuit of exobiological questions on the resistance to extreme environments and the origin and distribution of life. The Planetary and Space Simulation Facilities PSI of the Institute of Aerospace Medicine at DLR in Köln, Germany, providing high vacuum of controlled residual composition, ionizing radiation of a X-ray tube, polychromatic UV radiation in the range of 170-400 nm, VIS and IR or individual monochromatic UV wavelengths, and temperature regulation from -20°C to +80°C at the sample size individually or in selected combinations in 9 modular facilities of varying sizes are presented with selected experiments performed within.
DISFRAC Version 2.0 Users Guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cochran, Kristine B; Erickson, Marjorie A; Williams, Paul T
2013-01-01
DISFRAC is the implementation of a theoretical, multi-scale model for the prediction of fracture toughness in the ductile-to-brittle transition temperature (DBTT) region of ferritic steels. Empirically-derived models of the DBTT region cannot legitimately be extrapolated beyond the range of existing fracture toughness data. DISFRAC requires only tensile properties and microstructural information as input, and thus allows for a wider range of application than empirical, toughness data dependent models. DISFRAC is also a framework for investigating the roles of various microstructural and macroscopic effects on fracture behavior, including carbide particle sizes, grain sizes, strain rates, and material condition. DISFRAC s novelmore » approach is to assess the interaction effects of macroscopic conditions (geometry, loading conditions) with variable microstructural features on cleavage crack initiation and propagation. The model addresses all stages of the fracture process, from microcrack initiation within a carbide particle, to propagation of that crack through grains and across grain boundaries, finally to catastrophic failure of the material. The DISFRAC procedure repeatedly performs a deterministic analysis of microcrack initiation and propagation within a macroscopic crack plastic zone to calculate a critical fracture toughness value for each microstructural geometry set. The current version of DISFRAC, version 2.0, is a research code for developing and testing models related to cleavage fracture and transition toughness. The various models and computations have evolved significantly over the course of development and are expected to continue to evolve as testing and data collection continue. This document serves as a guide to the usage and theoretical foundations of DISFRAC v2.0. Feedback is welcomed and encouraged.« less
Cooper, Virgil N; Oshiro, Thomas; Cagnon, Christopher H; Bassett, Lawrence W; McLeod-Stockmann, Tyler M; Bezrukiy, Nikita V
2003-10-01
Digital detectors in mammography have wide dynamic range in addition to the benefit of decoupled acquisition and display. How wide the dynamic range is and how it compares to film-screen systems in the clinical x-ray exposure domain are unclear. In this work, we compare the effective dynamic ranges of film-screen and flat panel mammography systems, along with the dynamic ranges of their component image receptors in the clinical x-ray exposure domain. An ACR mammography phantom was imaged using variable mAs (exposure) values for both systems. The dynamic range of the contrast-limited film-screen system was defined as that ratio of mAs (exposure) values for a 26 kVp Mo/Mo (HVL=0.34 mm Al) beam that yielded passing phantom scores. The same approach was done for the noise-limited digital system. Data from three independent observers delineated a useful phantom background optical density range of 1.27 to 2.63, which corresponded to a dynamic range of 2.3 +/- 0.53. The digital system had a dynamic range of 9.9 +/- 1.8, which was wider than the film-screen system (p<0.02). The dynamic range of the film-screen system was limited by the dynamic range of the film. The digital detector, on the other hand, had an estimated dynamic range of 42, which was wider than the dynamic range of the digital system in its entirety by a factor of 4. The generator/tube combination was the limiting factor in determining the digital system's dynamic range.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gao, Zhiming; Curran, Scott; Daw, C Stuart
2013-01-01
In-cylinder blending of gasoline and diesel fuels to achieve low-temperature reactivity controlled compression ignition (RCCI) can reduce NOx and PM emissions while maintaining or improving brake thermal efficiency compared to conventional diesel combustion (CDC). Moreover, the dual-fueling RCCI is able to achieve these benefits by tailoring combustion reactivity over a wider range of engine operation than is possible with a single fuel. However, the currently demonstrated range of stable RCCI combustion just covers a portion of the engine speed-load range required in several light-duty drive cycles. This means that engines must switch from RCCI to CDC when speed and loadmore » fall outside of the stable RCCI range. In this study we investigated the impact of RCCI as it has recently been demonstrated on practical engine-out exhaust temperature and emissions by simulating a multi-mode RCCI-enabled vehicle operating over two urban and two highway driving cycles. To implement our simulations, we employed experimental engine maps for a multi-mode RCCI/CDC engine combined with a standard mid-size, automatic transmission, passenger vehicle in the Autonomie vehicle simulation platform. Our results include both detailed transient and cycle-averaged engine exhaust temperature and emissions for each case, and we note the potential implications of the modified exhaust properties on catalytic emissions control and utilization of waste heat recovery on future RCCI-enabled vehicles.« less
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.
Analysis of lomustine drug content in FDA-approved and compounded lomustine capsules.
KuKanich, Butch; Warner, Matt; Hahn, Kevin
2017-02-01
OBJECTIVE To determine the lomustine content (potency) in compounded and FDA-approved lomustine capsules. DESIGN Evaluation study. SAMPLE 2 formulations of lomustine capsules (low dose [7 to 11 mg] and high dose [40 to 48 mg]; 5 capsules/dose/source) from 3 compounders and from 1 manufacturer of FDA-approved capsules. PROCEDURES Lomustine content was measured by use of a validated high-pressure liquid chromatography method. An a priori acceptable range of 90% to 110% of the stated lomustine content was selected on the basis of US Pharmacopeia guidelines. RESULTS The measured amount of lomustine in all compounded capsules was less than the stated content (range, 59% to 95%) and was frequently outside the acceptable range (failure rate, 2/5 to 5/5). Coefficients of variation for lomustine content ranged from 4.1% to 16.7% for compounded low-dose capsules and from 1.1% to 10.8% for compounded high-dose capsules. The measured amount of lomustine in all FDA-approved capsules was slightly above the stated content (range, 104% to 110%) and consistently within the acceptable range. Coefficients of variation for lomustine content were 0.5% for low-dose and 2.3% for high-dose FDA-approved capsules. CONCLUSIONS AND CLINICAL RELEVANCE Compounded lomustine frequently did not contain the stated content of active drug and had a wider range of lomustine content variability than did the FDA-approved product. The sample size was small, and larger studies are needed to confirm these findings; however, we recommend that compounded veterinary formulations of lomustine not be used when appropriate doses can be achieved with FDA-approved capsules or combinations of FDA-approved capsules.
Using Drama to Support Literacy: Activities for Children Aged 7 to 14
ERIC Educational Resources Information Center
Goodwin, John
2006-01-01
The power of drama provides a real context for narrative writing, and in this book the tool kit of drama strategies has been laid out and used effectively by teachers across a wider range of imaginary contexts. Using drama makes possible a vast range of themes and story contexts which enthuse and hook children into the writing process. The real…
Gas Bubble Migration and Trapping in Porous Media: Pore-Scale Simulation
NASA Astrophysics Data System (ADS)
Mahabadi, Nariman; Zheng, Xianglei; Yun, Tae Sup; van Paassen, Leon; Jang, Jaewon
2018-02-01
Gas bubbles can be naturally generated or intentionally introduced in sediments. Gas bubble migration and trapping affect the rate of gas emission into the atmosphere or modify the sediment properties such as hydraulic and mechanical properties. In this study, the migration and trapping of gas bubbles are simulated using the pore-network model extracted from the 3D X-ray image of in situ sediment. Two types of bubble size distribution (mono-sized and distributed-sized cases) are used in the simulation. The spatial and statistical bubble size distribution, residual gas saturation, and hydraulic conductivity reduction due to the bubble trapping are investigated. The results show that the bubble size distribution becomes wider during the gas bubble migration due to bubble coalescence for both mono-sized and distributed-sized cases. And the trapped bubble fraction and the residual gas saturation increase as the bubble size increases. The hydraulic conductivity is reduced as a result of the gas bubble trapping. The reduction in hydraulic conductivity is apparently observed as bubble size and the number of nucleation points increase.
Thermal sensitivity of cold climate lizards and the importance of distributional ranges.
Bonino, Marcelo F; Moreno Azócar, Débora L; Schulte, James A; Abdala, Cristian S; Cruz, Félix B
2015-08-01
One of the fundamental goals in macroecology is to understand the relationship among species' geographic ranges, ecophysiology, and climate; however, the mechanisms underlying the distributional geographic patterns observed remain unknown for most organisms. In the case of ectotherms this is particularly important because the knowledge of these interactions may provide a robust framework for predicting the potential consequences of climate change in these organisms. Here we studied the relationship of thermal sensitivity and thermal tolerance in Patagonian lizards and their geographic ranges, proposing that species with wider distributions have broader plasticity and thermal tolerance. We predicted that lizard thermal physiology is related to the thermal characteristics of the environment. We also explored the presence of trade-offs of some thermal traits and evaluated the potential effects of a predicted scenario of climate change for these species. We examined sixteen species of Liolaemini lizards from Patagonia representing species with different geographic range sizes. We obtained thermal tolerance data and performance curves for each species in laboratory trials. We found evidence supporting the idea that higher physiological plasticity allows species to achieve broader distribution ranges compared to species with restricted distributions. We also found a trade-off between broad levels of plasticity and higher optimum temperatures of performance. Finally, results from contrasting performance curves against the highest environmental temperatures that lizards may face in a future scenario (year 2080) suggest that the activity of species occurring at high latitudes may be unaffected by predicted climatic changes. Copyright © 2015 Elsevier GmbH. All rights reserved.
Hollands, Gareth J; Shemilt, Ian; Marteau, Theresa M; Jebb, Susan A; Lewis, Hannah B; Wei, Yinghui; Higgins, Julian Pt; Ogilvie, David
2015-01-01
Background Overeating and harmful alcohol and tobacco use have been linked to the aetiology of various non-communicable diseases, which are among the leading global causes of morbidity and premature mortality. As people are repeatedly exposed to varying sizes and shapes of food, alcohol and tobacco products in environments such as shops, restaurants, bars and homes, this has stimulated public health policy interest in product size and shape as potential targets for intervention. Objectives 1) To assess the effects of interventions involving exposure to different sizes or sets of physical dimensions of a portion, package, individual unit or item of tableware on unregulated selection or consumption of food, alcohol or tobacco products in adults and children. 2) To assess the extent to which these effects may be modified by study, intervention and participant characteristics. Search methods We searched CENTRAL, MEDLINE, EMBASE, PsycINFO, eight other published or grey literature databases, trial registries and key websites up to November 2012, followed by citation searches and contacts with study authors. This original search identified eligible studies published up to July 2013, which are fully incorporated into the review. We conducted an updated search up to 30 January 2015 but further eligible studies are not yet fully incorporated due to their minimal potential to change the conclusions. Selection criteria Randomised controlled trials with between-subjects (parallel-group) or within-subjects (cross-over) designs, conducted in laboratory or field settings, in adults or children. Eligible studies compared at least two groups of participants, each exposed to a different size or shape of a portion of a food (including non-alcoholic beverages), alcohol or tobacco product, its package or individual unit size, or of an item of tableware used to consume it, and included a measure of unregulated selection or consumption of food, alcohol or tobacco. Data collection and analysis We applied standard Cochrane methods to select eligible studies for inclusion and to collect data and assess risk of bias. We calculated study-level effect sizes as standardised mean differences (SMDs) between comparison groups, measured as quantities selected or consumed. We combined these results using random-effects meta-analysis models to estimate summary effect sizes (SMDs with 95% confidence intervals (CIs)) for each outcome for size and shape comparisons. We rated the overall quality of evidence using the GRADE system. Finally, we used meta-regression analysis to investigate statistical associations between summary effect sizes and variant study, intervention or participant characteristics. Main results The current version of this review includes 72 studies, published between 1978 and July 2013, assessed as being at overall unclear or high risk of bias with respect to selection and consumption outcomes. Ninety-six per cent of included studies (69/72) manipulated food products and 4% (3/72) manipulated cigarettes. No included studies manipulated alcohol products. Forty-nine per cent (35/72) manipulated portion size, 14% (10/72) package size and 21% (15/72) tableware size or shape. More studies investigated effects among adults (76% (55/72)) than children and all studies were conducted in high-income countries - predominantly in the USA (81% (58/72)). Sources of funding were reported for the majority of studies, with no evidence of funding by agencies with possible commercial interests in their results. A meta-analysis of 86 independent comparisons from 58 studies (6603 participants) found a small to moderate effect of portion, package, individual unit or tableware size on consumption of food (SMD 0.38, 95% CI 0.29 to 0.46), providing moderate quality evidence that exposure to larger sizes increased quantities of food consumed among children (SMD 0.21, 95% CI 0.10 to 0.31) and adults (SMD 0.46, 95% CI 0.40 to 0.52). The size of this effect suggests that, if sustained reductions in exposure to larger-sized food portions, packages and tableware could be achieved across the whole diet, this could reduce average daily energy consumed from food by between 144 and 228 kcal (8.5% to 13.5% from a baseline of 1689 kcal) among UK children and adults. A meta-analysis of six independent comparisons from three studies (108 participants) found low quality evidence for no difference in the effect of cigarette length on consumption (SMD 0.25, 95% CI -0.14 to 0.65). One included study (50 participants) estimated a large effect on consumption of exposure to differently shaped tableware (SMD 1.17, 95% CI 0.57 to 1.78), rated as very low quality evidence that exposure to shorter, wider bottles (versus taller, narrower bottles) increased quantities of water consumed by young adult participants. A meta-analysis of 13 independent comparisons from 10 studies (1164 participants) found a small to moderate effect of portion or tableware size on selection of food (SMD 0.42, 95% CI 0.24 to 0.59), rated as moderate quality evidence that exposure to larger sizes increased the quantities of food people selected for subsequent consumption. This effect was present among adults (SMD 0.55, 95% CI 0.35 to 0.75) but not children (SMD 0.14, 95% CI -0.06 to 0.34). In addition, a meta-analysis of three independent comparisons from three studies (232 participants) found a very large effect of exposure to differently shaped tableware on selection of non-alcoholic beverages (SMD 1.47, 95% CI 0.52 to 2.43), rated as low quality evidence that exposure to shorter, wider (versus taller, narrower) glasses or bottles increased the quantities selected for subsequent consumption among adults (SMD 2.31, 95% CI 1.79 to 2.83) and children (SMD 1.03, 95% CI 0.41 to 1.65). Authors' conclusions This review found that people consistently consume more food and drink when offered larger-sized portions, packages or tableware than when offered smaller-sized versions. This suggests that policies and practices that successfully reduce the size, availability and appeal of larger-sized portions, packages, individual units and tableware can contribute to meaningful reductions in the quantities of food (including non-alcoholic beverages) people select and consume in the immediate and short term. However, it is uncertain whether reducing portions at the smaller end of the size range can be as effective in reducing food consumption as reductions at the larger end of the range. We are unable to highlight clear implications for tobacco or alcohol policy due to identified gaps in the current evidence base. PLAIN LANGUAGE SUMMARY Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco Review question We reviewed the evidence to establish by how much the amounts of food, alcohol or tobacco adults and children select or consume change in response to being presented with larger or smaller-sized (or differently shaped) portions or packages of these products, or of items of tableware (such as plates or glasses) used to consume them. Study characteristics This review includes 72 randomised controlled trials (RCTs) published up to July 2013 that compared at least two groups of participants, each presented with a different size of a portion, package or item of tableware. Included studies measured the amounts of food, alcohol or tobacco selected and/or consumed by participants, typically over a period of one day or less. Almost all of the included studies investigated food, with only three tobacco studies and no alcohol studies found. Almost all assessed participants' responses to different sizes rather than different shapes. The average age of participants in the different studies ranged from three to 55 years, with more studies involving adults than children and most conducted in the USA. Sources of funding were reported for the majority of studies and there was no evidence of study funding by agencies with commercial interests in their results. Key findings and quality of evidence Effects of size on consumption: We found evidence that people consistently ate more food or drank more non-alcoholic drinks when offered larger-sized portions, packages or items of tableware than when offered smaller-sized versions. We estimate the size of this effect to be small to moderate among both children and adults. If an effect of this size were sustained across the whole diet it would be equivalent to around a 12% to 16% change in average daily energy intake from food among UK adults. We rated the overall quality of the evidence for this effect as moderate, due to concern about study limitations arising from incomplete or unclear reporting of methods and procedures. From three tobacco studies, we found no effect of longer compared with shorter cigarettes on the amounts of tobacco consumed. We rated the overall quality of evidence for this effect as low due to concerns about study limitations and not having enough evidence. Effects of shape on consumption: One study found that adults provided with shorter, wider bottles drank larger amounts of water from them, having already poured more, compared with those provided with taller, narrower bottles. However, we rated the quality of this evidence as very low, due to very serious concerns about study limitations and not having enough evidence (only one study with outcome data from 50 participants). Effects of size on selection: We further found that adults, but not children, consistently chose (selected) more food (including non-alcoholic drinks) when offered larger-sized portions, packages or items of tableware than when offered smaller-sized versions. The estimated size of this effect was again small to moderate. We rated the overall quality of the evidence for this effect as moderate, due to concern about study limitations. Effects of shape on selection: Evidence from three studies suggested that adults and children provided with shorter, wider bottles or glasses selected increased quantities of non-alcoholic beverages for subsequent consumption, compared with those provided with taller, narrower bottles or glasses. We rated the quality of this evidence as low, again due to concerns about study limitations and unexplained variation in effects between the three studies. Conclusions Overall, this review provides the most conclusive evidence to date that acting to reduce the size, availability and appeal of larger-sized portions, packages and tableware has potential to reduce the quantities of food that people select and consume by meaningful amounts. However, it is uncertain whether reducing portions at the smaller end of the size range can be as effective in reducing food consumption as reductions at the larger end of the range. Our findings highlight the need for further research that aims to reduce uncertainties about these effects and address identified gaps in the evidence base, including not having enough evidence for longer-term effects and the absence of evidence about alcohol products. PMID:26368271
Variations in tooth size and arch dimensions in Malay schoolchildren.
Hussein, Khalid W; Rajion, Zainul A; Hassan, Rozita; Noor, Siti Noor Fazliah Mohd
2009-11-01
To compare the mesio-distal tooth sizes and dental arch dimensions in Malay boys and girls with Class I, Class II and Class III malocclusions. The dental casts of 150 subjects (78 boys, 72 girls), between 12 and 16 years of age, with Class I, Class II and Class III malocclusions were used. Each group consisted of 50 subjects. An electronic digital caliper was used to measure the mesio-distal tooth sizes of the upper and lower permanent teeth (first molar to first molar), the intercanine and intermolar widths. The arch lengths and arch perimeters were measured with AutoCAD software (Autodesk Inc., San Rafael, CA, U.S.A.). The mesio-distal dimensions of the upper lateral incisors and canines in the Class I malocclusion group were significantly smaller than the corresponding teeth in the Class III and Class II groups, respectively. The lower canines and first molars were significantly smaller in the Class I group than the corresponding teeth in the Class II group. The lower intercanine width was significantly smaller in the Class II group as compared with the Class I group, and the upper intermolar width was significantly larger in Class III group as compared with the Class II group. There were no significant differences in the arch perimeters or arch lengths. The boys had significantly wider teeth than the girls, except for the left lower second premolar. The boys also had larger upper and lower intermolar widths and lower intercanine width than the girls. Small, but statistically significant, differences in tooth sizes are not necessarily accompanied by significant arch width, arch length or arch perimeter differences. Generally, boys have wider teeth, larger lower intercanine width and upper and lower intermolar widths than girls.
Jorge, Fátima; Perera, Ana; Poulin, Robert; Roca, Vicente; Carretero, Miguel A
2018-01-01
Episodes of expansion and isolation in geographic range over space and time, during which parasites have the opportunity to expand their host range, are linked to the development of host-parasite mosaic assemblages and parasite diversification. In this study, we investigated whether island colonization events lead to host range oscillations in a taxon of host-specific parasitic nematodes of the genus Spauligodon in the Canary Islands. We further investigated whether range oscillations also resulted in shifts in host breadth (i.e., specialization), as expected for parasites on islands. Parasite phylogeny and divergence time estimates were inferred from molecular data with Bayesian methods. Host divergence times were set as calibration priors after a priori evaluation with a global-fit method of which individual host-parasite associations likely represent cospeciation links. Parasite colonization history was reconstructed, followed by an estimation of oscillation events and specificity level. The results indicate the presence of four Spauligodon clades in the Canary Islands, which originated from at least three different colonization events. We found evidence of host range oscillations to truly novel hosts, which in one case led to higher diversification. Contemporary host-parasite associations show strong host specificity, suggesting that changes in host breadth were limited to the shift period. Lineages with more frequent and wider taxonomic host range oscillations prior to the initial colonization event showed wider range oscillations during colonization and diversification within the archipelago. Our results suggest that a lineage's evolutionary past may be the best indicator of a parasite's potential for future range expansions. © 2017 John Wiley & Sons Ltd.
Recent Advances in Modeling Hugoniots with Cheetah
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glaesemann, K R; Fried, L E
2005-07-26
We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.
Scanning Shack-Hartmann wavefront sensor
NASA Astrophysics Data System (ADS)
Molebny, Vasyl V.
2004-09-01
Criss-crossing of focal images is the cause of a narrow dynamic range in Shack-Hartmann sensors. Practically, aberration range wider than +/-3 diopters can not be measured. A method has been proposed for ophthalmologic applications using a rarefied lenslet array through which a wave front is projected with the successive step-by-step changing of the global tilt. The data acquired in each step are accumulated and processed. In experimental setup, a doubled dynamic range was achieved with four steps of wave front tilting.
Recent Advances in Modeling Hugoniots with Cheetah
NASA Astrophysics Data System (ADS)
Glaesemann, K. R.; Fried, L. E.
2006-07-01
We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.
RANGE INCREASER FOR PNEUMATIC GAUGES
Fowler, A.H.; Seaborn, G.B. Jr.
1960-09-27
An improved pneumatic gage is offered in which the linear range has been increased without excessive air consumption. This has been accomplished by providing an expansible antechamber connected to the nozzle of the gage so that the position of the nozzle with respect to the workpiece is varied automatically by variation in pressure within the antechamber. This arrangement ensures that the nozzle-to-workpiece clearance is maintained within certain limits, thus obtaining a linear relation of air flow to nozzle-to-workpiece clearance over a wider range.
Adjustable Tuning Spring for Bellows Pump
NASA Technical Reports Server (NTRS)
Green, G. L.; Tu Duc, D.; Hooper, S.
1985-01-01
Adjustable leaf spring increases maximum operating pressure of pump from 2 to over 60 psi (13 to over 400 kN/m2). Small commercial bellows pump using ac-powered electromagnet to vibrate bellows at mechanical resonance modified to operate over wider pressure range.
ERIC Educational Resources Information Center
Harris, Philip R.
1985-01-01
Looks at changes in the manager's role due to technological advancement in the workplace. Discusses wider range of uses for computers (analysis, decision making, communications, planning, tracking trends), importance of supervisor training, cyberphobia (fear of new technology), cyberphrenia (addiction to new technology), and the effect of a work…
Community College Faculty: Making the Paradigm Shift.
ERIC Educational Resources Information Center
Van Ast, John
1999-01-01
Discusses the need for paradigm shifts during the next decade that address the following challenges: (1) the wider range of student ability and mastery; (2) high attrition rates; and (3) differing and often contradicting perceptions of students, faculty, and administration. Contains 180 references. (TGO)
Distribution and diversity of cytotypes in Dianthus broteri as evidenced by genome size variations
Balao, Francisco; Casimiro-Soriguer, Ramón; Talavera, María; Herrera, Javier; Talavera, Salvador
2009-01-01
Background and Aims Studying the spatial distribution of cytotypes and genome size in plants can provide valuable information about the evolution of polyploid complexes. Here, the spatial distribution of cytological races and the amount of DNA in Dianthus broteri, an Iberian carnation with several ploidy levels, is investigated. Methods Sample chromosome counts and flow cytometry (using propidium iodide) were used to determine overall genome size (2C value) and ploidy level in 244 individuals of 25 populations. Both fresh and dried samples were investigated. Differences in 2C and 1Cx values among ploidy levels within biogeographical provinces were tested using ANOVA. Geographical correlations of genome size were also explored. Key Results Extensive variation in chromosomes numbers (2n = 2x = 30, 2n = 4x = 60, 2n = 6x = 90 and 2n = 12x =180) was detected, and the dodecaploid cytotype is reported for the first time in this genus. As regards cytotype distribution, six populations were diploid, 11 were tetraploid, three were hexaploid and five were dodecaploid. Except for one diploid population containing some triploid plants (2n = 45), the remaining populations showed a single cytotype. Diploids appeared in two disjunct areas (south-east and south-west), and so did tetraploids (although with a considerably wider geographic range). Dehydrated leaf samples provided reliable measurements of DNA content. Genome size varied significantly among some cytotypes, and also extensively within diploid (up to 1·17-fold) and tetraploid (1·22-fold) populations. Nevertheless, variations were not straightforwardly congruent with ecology and geographical distribution. Conclusions Dianthus broteri shows the highest diversity of cytotypes known to date in the genus Dianthus. Moreover, some cytotypes present remarkable internal genome size variation. The evolution of the complex is discussed in terms of autopolyploidy, with primary and secondary contact zones. PMID:19633312
Lozano-Cortés, Diego F; Berumen, Michael L
2016-04-30
Coral colony size-frequency distributions can be used to assess population responses to local environmental conditions and disturbances. In this study, we surveyed juvenile pocilloporids, herbivorous fish densities, and algal cover in the central and southern Saudi Arabian Red Sea. We sampled nine reefs with different disturbance histories along a north-south natural gradient of physicochemical conditions (higher salinity and wider temperature fluctuations in the north, and higher turbidity and productivity in the south). Since coral populations with negatively skewed size-frequency distributions have been associated with unfavorable environmental conditions, we expected to find more negative distributions in the southern Red Sea, where corals are potentially experiencing suboptimal conditions. Although juvenile coral and parrotfish densities differed significantly between the two regions, mean colony size and size-frequency distributions did not. Results suggest that pocilloporid colony size-frequency distribution may not be an accurate indicator of differences in biological or oceanographic conditions in the Red Sea. Copyright © 2015 Elsevier Ltd. All rights reserved.
Enabling Near Real-Time Remote Search for Fast Transient Events with Lossy Data Compression
NASA Astrophysics Data System (ADS)
Vohl, Dany; Pritchard, Tyler; Andreoni, Igor; Cooke, Jeffrey; Meade, Bernard
2017-09-01
We present a systematic evaluation of JPEG2000 (ISO/IEC 15444) as a transport data format to enable rapid remote searches for fast transient events as part of the Deeper Wider Faster programme. Deeper Wider Faster programme uses 20 telescopes from radio to gamma rays to perform simultaneous and rapid-response follow-up searches for fast transient events on millisecond-to-hours timescales. Deeper Wider Faster programme search demands have a set of constraints that is becoming common amongst large collaborations. Here, we focus on the rapid optical data component of Deeper Wider Faster programme led by the Dark Energy Camera at Cerro Tololo Inter-American Observatory. Each Dark Energy Camera image has 70 total coupled-charged devices saved as a 1.2 gigabyte FITS file. Near real-time data processing and fast transient candidate identifications-in minutes for rapid follow-up triggers on other telescopes-requires computational power exceeding what is currently available on-site at Cerro Tololo Inter-American Observatory. In this context, data files need to be transmitted rapidly to a foreign location for supercomputing post-processing, source finding, visualisation and analysis. This step in the search process poses a major bottleneck, and reducing the data size helps accommodate faster data transmission. To maximise our gain in transfer time and still achieve our science goals, we opt for lossy data compression-keeping in mind that raw data is archived and can be evaluated at a later time. We evaluate how lossy JPEG2000 compression affects the process of finding transients, and find only a negligible effect for compression ratios up to 25:1. We also find a linear relation between compression ratio and the mean estimated data transmission speed-up factor. Adding highly customised compression and decompression steps to the science pipeline considerably reduces the transmission time-validating its introduction to the Deeper Wider Faster programme science pipeline and enabling science that was otherwise too difficult with current technology.
Efficiency and flexibility using implicit methods within atmosphere dycores
NASA Astrophysics Data System (ADS)
Evans, K. J.; Archibald, R.; Norman, M. R.; Gardner, D. J.; Woodward, C. S.; Worley, P.; Taylor, M.
2016-12-01
A suite of explicit and implicit methods are evaluated for a range of configurations of the shallow water dynamical core within the spectral-element Community Atmosphere Model (CAM-SE) to explore their relative computational performance. The configurations are designed to explore the attributes of each method under different but relevant model usage scenarios including varied spectral order within an element, static regional refinement, and scaling to large problem sizes. The limitations and benefits of using explicit versus implicit, with different discretizations and parameters, are discussed in light of trade-offs such as MPI communication, memory, and inherent efficiency bottlenecks. For the regionally refined shallow water configurations, the implicit BDF2 method is about the same efficiency as an explicit Runge-Kutta method, without including a preconditioner. Performance of the implicit methods with the residual function executed on a GPU is also presented; there is speed up for the residual relative to a CPU, but overwhelming transfer costs motivate moving more of the solver to the device. Given the performance behavior of implicit methods within the shallow water dynamical core, the recommendation for future work using implicit solvers is conditional based on scale separation and the stiffness of the problem. The strong growth of linear iterations with increasing resolution or time step size is the main bottleneck to computational efficiency. Within the hydrostatic dynamical core, of CAM-SE, we present results utilizing approximate block factorization preconditioners implemented using the Trilinos library of solvers. They reduce the cost of linear system solves and improve parallel scalability. We provide a summary of the remaining efficiency considerations within the preconditioner and utilization of the GPU, as well as a discussion about the benefits of a time stepping method that provides converged and stable solutions for a much wider range of time step sizes. As more complex model components, for example new physics and aerosols, are connected in the model, having flexibility in the time stepping will enable more options for combining and resolving multiple scales of behavior.
A Model for Evaluating Tactually Assistive Devices.
ERIC Educational Resources Information Center
Terrio, Lee; Haas, William
1986-01-01
Audiometric instruments and techniques adopted to measure tactual cueing characteristics of the Radioear B70A and the Siemens Fonator electromechanical vibrators were used by young adults. The Siemens Phonator demonstrated a wider suprathreshold operating range than did the Radioear B70A. (Author/CL)
Proteus mirabilis interkingdom swarming signals attract blow flies
USDA-ARS?s Scientific Manuscript database
Flies transport specific bacteria with their larvae which provides a wider range of nutrients for those bacteria. Our hypothesis was that this symbiotic interaction may depend on interkingdom signaling. We obtained Proteus mirabilis from the salivary glands of the blow fly Lucilia sericat. This s...
John R. Jones
1985-01-01
Quaking aspen is the most widely distributed native North American tree species (Little 1971, Sargent 1890). It grows in a great diversity of regions, environments, and communities (Harshberger 1911). Only one deciduous tree species in the world, the closely related Eurasian aspen (Populus tremula), has a wider range (Weigle and Frothingham 1911)....
Jung, Sung Yong; Yeom, Eunseop
2017-01-01
Platelet aggregation affects the surrounding blood flow and usually occurs where a blood vessel is narrowed as a result of atherosclerosis. The relationship between blood flow and platelet aggregation is not yet fully understood. This study proposes a microfluidic method to measure the velocity and platelet aggregation simultaneously by combining the micro-particle image velocimetry technique and a correlation mapping method. The blood flow and platelet adhesion procedure in a stenotic micro-channel with 90% severity were observed for a relatively long period of 4 min. In order to investigate the effect of tile size on the detection of platelet adhesion, 2D correlation coefficients were evaluated with binary images obtained by manual labeling and the correlation mapping method with different sizes of the square tile ranging from 3 to 50 pixels. The maximum 2D correlation coefficient occurred with the optimum tile size of 5 × 5 pixels. Since the blood flow and platelet aggregation are mutually influenced by each other, blood flow and platelet adhesion were continuously varied. When there was no platelet adhesion (t = 0 min), typical blood flow is observed. The blood flow passes through the whole channel smoothly, and jet-like flow occurs in the post-stenosis region. However, the flow pattern changes when platelet adhesion starts at the stenosis apex and after the stenosis. These adhesions induce narrow high velocity regions to become wider over a range of area from upstream to downstream of the stenosis. Separated jet-like flows with two high velocity regions are also created. The changes in flow patterns may alter the patterns of platelet adhesion. As the area of the plate adhesion increases, the platelets plug the micro-channel and there is only a small amount of blood flow, finally. The microfluidic method could provide new insights for better understanding of the interactions between platelet aggregation and blood flow in various physiological conditions. PMID:28798854
Jung, Sung Yong; Yeom, Eunseop
2017-03-01
Platelet aggregation affects the surrounding blood flow and usually occurs where a blood vessel is narrowed as a result of atherosclerosis. The relationship between blood flow and platelet aggregation is not yet fully understood. This study proposes a microfluidic method to measure the velocity and platelet aggregation simultaneously by combining the micro-particle image velocimetry technique and a correlation mapping method. The blood flow and platelet adhesion procedure in a stenotic micro-channel with 90% severity were observed for a relatively long period of 4 min. In order to investigate the effect of tile size on the detection of platelet adhesion, 2D correlation coefficients were evaluated with binary images obtained by manual labeling and the correlation mapping method with different sizes of the square tile ranging from 3 to 50 pixels. The maximum 2D correlation coefficient occurred with the optimum tile size of 5 × 5 pixels. Since the blood flow and platelet aggregation are mutually influenced by each other, blood flow and platelet adhesion were continuously varied. When there was no platelet adhesion (t = 0 min), typical blood flow is observed. The blood flow passes through the whole channel smoothly, and jet-like flow occurs in the post-stenosis region. However, the flow pattern changes when platelet adhesion starts at the stenosis apex and after the stenosis. These adhesions induce narrow high velocity regions to become wider over a range of area from upstream to downstream of the stenosis. Separated jet-like flows with two high velocity regions are also created. The changes in flow patterns may alter the patterns of platelet adhesion. As the area of the plate adhesion increases, the platelets plug the micro-channel and there is only a small amount of blood flow, finally. The microfluidic method could provide new insights for better understanding of the interactions between platelet aggregation and blood flow in various physiological conditions.
A review of vagus nerve stimulation as a therapeutic intervention
Johnson, Rhaya L; Wilson, Christopher G
2018-01-01
In this review, we provide an overview of the US Food and Drug Administration (FDA)-approved clinical uses of vagus nerve stimulation (VNS) as well as information about the ongoing studies and preclinical research to expand the use of VNS to additional applications. VNS is currently FDA approved for therapeutic use in patients aged >12 years with drug-resistant epilepsy and depression. Recent studies of VNS in in vivo systems have shown that it has anti-inflammatory properties which has led to more preclinical research aimed at expanding VNS treatment across a wider range of inflammatory disorders. Although the signaling pathway and mechanism by which VNS affects inflammation remain unknown, VNS has shown promising results in treating chronic inflammatory disorders such as sepsis, lung injury, rheumatoid arthritis (RA), and diabetes. It is also being used to control pain in fibromyalgia and migraines. This new preclinical research shows that VNS bears the promise of being applied to a wider range of therapeutic applications. PMID:29844694
NASA Astrophysics Data System (ADS)
Qing, Jiasheng; Wang, Lei; Dou, Kun; Wang, Bao; Liu, Qing
2016-06-01
The influence of V-N microalloying on the high-temperature mechanical behavior of high strength weathering steel is discussed through thermomechanical simulation experiment. The difference of tensile strength caused by variation of [%V][%N] appears after proeutectoid phase change, and the higher level of [%V][%N] is, the stronger the tensile strength tends to be. The ductility trough apparently becomes deeper and wider with the increase of [%V][%N]. When the level of [%V][%N] reaches to 1.7 × 10-3, high strength weathering steel shows almost similar reduction of area to 0.03% Nb-containing steel in the temperature range of 800-900°, however, the ductility trough at the low-temperature stage is wider than that of Nb-containing steel. Moreover, the net crack defect of bloom is optimized through the stable control of N content in low range under the precondition of high strength weathering steel with sufficient strength.
Siblings of Children with Autism: the Siblings Embedded Systems Framework.
Kovshoff, Hanna; Cebula, Katie; Tsai, Hsiao-Wei Joy; Hastings, Richard P
2017-01-01
A range of interacting factors/mechanisms at the individual, family, and wider systems levels influences siblings living in families where one sibling has autism. We introduce the Sibling Embedded Systems Framework which aims to contextualise siblings' experience and characterise the multiple and interacting factors influencing family and, in particular, sibling outcomes. Findings from studies that have reported outcomes for siblings of children with autism are equivocal, ranging from negative impact, no difference, to positive experience. This is likely due to the complex nature of understanding the sibling experience. We focus on particular elements of the framework and review recent novel literature to help guide future directions for research and practice including the influence of culture, methodological considerations, and wider participatory methods. The Siblings Embedded System Framework can be used to understand interactive factors that affect sibling adjustment and to develop clinically, educationally and empirically based work that aims to enhance and support sibling adjustment, relationships, and well-being in families of children with autism.
Design and Implementation of a new Autonomous Sensor Fish to Support Advanced Hydropower Development
Deng, Zhiqun; Lu, Jun; Myjak, Mitchell J.; ...
2014-11-04
Acceleration in development of additional conventional hydropower requires tools and methods to perform laboratory and in-field validation of turbine performance and fish passage claims. The new-generation Sensor Fish has been developed with more capabilities to accommodate a wider range of users over a wider range of turbine designs and operating environments. It provides in situ measurements of three dimensional (3D) accelerations, 3D rotational velocities, 3D orientation, pressure, and temperature at a sampling frequency of 2048 Hz. It also has an automatic floatation system and built-in radio frequency transmitter for recovery. The relative errors of the pressure, acceleration and rotational velocitymore » were within ±2%, ±5%, and ±5%, respectively. The accuracy of orientation was within ±4° and accuracy of temperature was ±2°C. It is being deployed to evaluate the biological effects of turbines or other hydraulic structures in several countries.« less
2011-04-25
must adapt its planning to vehicle size, shape, wheelbase, wheel and axle configuration, the specific obstacle-crossing capabilities of the vehicle...scalability of the ANS is a consequence of making each sensing modality capable of performing reasonable perception tasks while allowing a wider...autonomous system design achieves flexibility by exploiting redundant sensing modalities where possible, and by a decision-making process that
The effect of cultural interaction on cumulative cultural evolution.
Nakahashi, Wataru
2014-07-07
Cultural transmission and cultural evolution are important for animals, especially for humans. I developed a new analytical model of cultural evolution, in which each newborn learns cultural traits from multiple individuals (exemplars) in parental generation, individually explores around learned cultural traits, judges the utility of known cultural traits, and adopts a mature cultural trait. Cultural evolutionary speed increases when individuals explore a wider range of cultural traits, accurately judge the skill level of cultural traits (strong direct bias), do not strongly conform to the population mean, increase the exploration range according to the variety of socially learned cultural traits (condition dependent exploration), and make smaller errors in social learning. Number of exemplars, population size, similarity of cultural traits between exemplars, and one-to-many transmission have little effect on cultural evolutionary speed. I also investigated how cultural interaction between two populations with different mean skill levels affects their cultural evolution. A population sometimes increases in skill level more if it encounters a less skilled population than if it does not encounter anyone. A less skilled population sometimes exceeds a more skilled population in skill level by cultural interaction between both populations. The appropriateness of this analytical method is confirmed by individual-based simulations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Boundary overlap for medical image segmentation evaluation
NASA Astrophysics Data System (ADS)
Yeghiazaryan, Varduhi; Voiculescu, Irina
2017-03-01
All medical image segmentation algorithms need to be validated and compared, and yet no evaluation framework is widely accepted within the imaging community. Collections of segmentation results often need to be compared and ranked by their effectiveness. Evaluation measures which are popular in the literature are based on region overlap or boundary distance. None of these are consistent in the way they rank segmentation results: they tend to be sensitive to one or another type of segmentation error (size, location, shape) but no single measure covers all error types. We introduce a new family of measures, with hybrid characteristics. These measures quantify similarity/difference of segmented regions by considering their overlap around the region boundaries. This family is more sensitive than other measures in the literature to combinations of segmentation error types. We compare measure performance on collections of segmentation results sourced from carefully compiled 2D synthetic data, and also on 3D medical image volumes. We show that our new measure: (1) penalises errors successfully, especially those around region boundaries; (2) gives a low similarity score when existing measures disagree, thus avoiding overly inflated scores; and (3) scores segmentation results over a wider range of values. We consider a representative measure from this family and the effect of its only free parameter on error sensitivity, typical value range, and running time.
Gehl, Julie; Sersa, Gregor; Matthiessen, Louise Wichmann; Muir, Tobian; Soden, Declan; Occhini, Antonio; Quaglino, Pietro; Curatolo, Pietro; Campana, Luca G; Kunte, Christian; Clover, A James P; Bertino, Giulia; Farricha, Victor; Odili, Joy; Dahlstrom, Karin; Benazzo, Marco; Mir, Lluis M
2018-03-25
Electrochemotherapy is now in routine clinical use to treat cutaneous metastases of any histology, and is listed in national and international guidelines for cutaneous metastases and primary skin cancer. Electrochemotherapy is used by dermatologists, surgeons, and oncologists, and for different degrees and manifestations of metastases to skin and primary skin tumours not amenable to surgery. This treatment utilises electric pulses to permeabilize cell membranes in tumours, thus allowing a dramatic increase of the cytotoxicity of anti-cancer agents. Response rates, often after only one treatment, are very high across all tumour types. The most frequent indications are cutaneous metastases from malignant melanoma and breast cancer. In 2006, standard operating procedures (SOPs) were written for this novel technology, greatly facilitating introduction and dissemination of the therapy. Since then considerable experience has been obtained treating a wider range of tumour histologies and increasing size of tumours which was not originally thought possible. A pan-European expert panel drawn from a range of disciplines from dermatology, general surgery, head and neck surgery, plastic surgery, and oncology met to form a consensus opinion to update the SOPs based on the experience obtained. This paper contains these updated recommendations for indications for electrochemotherapy, pre-treatment information and evaluation, treatment choices, as well as follow-up.
Samolczyk, Mary; Vallance, James W.; Cubley, Joel; Osborn, Gerald; Clark, Douglas H.
2016-01-01
The oldest postglacial lapilli–ash tephra recognized in sedimentary records surrounding Mount Rainier (Washington State, USA) is R tephra, a very early Holocene deposit that acts as an important stratigraphic and geochronologic marker bed. This multidisciplinary study incorporates tephrostratigraphy, radiocarbon dating, petrography, and electron microprobe analysis to characterize R tephra. Tephra samples were collected from Tipsoo Lake and a stream-cut exposure in the Cowlitz Divide area of Mount Rainier National Park. Field evidence from 25 new sites suggests that R tephra locally contains internal bedding and has a wider distribution than previously reported. Herein, we provide the first robust suite of geochemical data that characterize the tephra. Glass compositions are heterogeneous, predominantly ranging from andesite to rhyolite in ash- to lapilli-sized clasts. The mineral assemblage consists of plagioclase, orthopyroxene, clinopyroxene, and magnetite with trace apatite and ilmenite. Subaerial R tephra deposits appear more weathered in hand sample than subaqueous deposits, but weathering indices suggest negligible chemical weathering in both deposits. Statistical analysis of radiocarbon ages provides a median age for R tephra of ∼10 050 cal years BP, and a 2σ error range between 9960 and 10 130 cal years BP.
Wang, Xiaomeng; Li, Minghui; Song, Xiaojie; Chen, Zhihao; Wu, Bingdang; Zhang, Shujuan
2016-09-06
The nontoxicity of titanium (Ti) and the potential to produce valuable photocatalysts from the final coagulated sludge constitute the main advantages of Ti-based coagulants over conventional ones. However, the low effluent pH and the too-fast hydrolysis limit the wide application of Ti-salt coagulants. Prehydrolysis, to some extent, is helpful to improve the coagulation performance of Ti-salt coagulants. However, the prehydrolyzed polytitanium chloride (PTC) still suffers from narrow applicable dose/pH range. A novel and efficient Ti-based coagulant, denoted as titanium xerogel coagulant (TXC), was successfully prepared by the sol-gel method with TiCl4 as the precursor and acetylacetone as a modifying agent. Compared with TiCl4, a PTC, and a commercial polyferric sulfate, the resulting TXC possessed a larger floc size, better settling property, and wider applicable coagulant dose/pH range. Moreover, the effluent pH after TXC coagulation was not significantly reduced, avoiding the corrosion problem sometimes caused by the low effluent pH. TXC exhibited good coagulation performance for several real wastewaters, especially for the wastewaters of low turbidity. These results demonstrate that gelation was a more effective strategy than prehydrolysis to overcome the inherent weaknesses of Ti salts as a type of promising coagulants.
Hughes, Lorie L.; Wang, Molin; Page, David L.; Gray, Robert; Solin, Lawrence J.; Davidson, Nancy E.; Lowen, Mary Ann; Ingle, James N.; Recht, Abram; Wood, William C.
2009-01-01
Purpose To determine the risk of ipsilateral breast events in patients with ductal carcinoma in situ (DCIS) treated with local excision without irradiation. Patients and Methods Patients with either low- or intermediate-grade DCIS measuring 2.5 cm or smaller, or high-grade DCIS measuring 1 cm or smaller who had microscopic margin widths of 3 mm or wider and no residual calcifications on postoperative mammograms were eligible for a prospective trial conducted from 1997 to 2002 by the Eastern Cooperative Oncology Group and North Central Cancer Treatment Group. Patients entered in 2000 and later could take tamoxifen if they wished. Median age at last surgery for the entire population was 60 years (range, 28 to 88 years), and median tumor sizes in the two strata were 6 mm and 5 mm, respectively. Results With a median follow-up of 6.2 years, the 5-year rate of ipsilateral breast events in the 565 eligible patients in the low/intermediate grade stratum was 6.1% (95% CI, 4.1% to 8.2%). With a median follow-up of 6.7 years, this incidence for the 105 eligible patients in the high-grade stratum was 15.3% (95% CI, 8.2% to 22.5%). Conclusion Rigorously evaluated and selected patients with low- to intermediate-grade DCIS with margins 3 mm or wider had an acceptably low rate of ipsilateral breast events at 5 years after excision without irradiation. Patients with high-grade lesions had a much higher rate, suggesting that excision alone is inadequate treatment. Further follow-up is necessary to document long-term results. PMID:19826126
Thermostatic Valves Containing Silicone-Oil Actuators
NASA Technical Reports Server (NTRS)
Bhandari, Pradeep; Birur, Gajanana C.; Bame, David P.; Karlmann, Paul B.; Prina, Mauro; Young, William; Fisher, Richard
2009-01-01
Flow-splitting and flow-mixing thermally actuated spool valves have been developed for controlling flows of a heat-transfer fluid in a temperature-regulation system aboard the Mars Science Laboratory (MSL) rover. Valves like these could also be useful in terrestrial temperature-regulation systems, including automobile air-conditioning systems and general refrigeration systems. These valves are required to provide smoother actuation over a wider temperature range than the flow-splitting, thermally actuated spool valves used in the Mars Explorer Rover (MER). Also, whereas the MER valves are unstable (tending to oscillate) in certain transition temperature ranges, these valves are required not to oscillate. The MER valves are actuated by thermal expansion of a wax against spring-loaded piston rods (as in common automotive thermostats). The MSL valves contain similar actuators that utilize thermal expansion of a silicone oil, because silicone-oil actuators were found to afford greater and more nearly linear displacements, needed for smoother actuation, over the required wider temperature range. The MSL valves also feature improved spool designs that reflect greater understanding of fluid dynamics, consideration of pressure drops in valves, and a requirement for balancing of pressures in different flow branches.
Bis(Dioxolene)Bis(Pyridine)Ruthenium Redox Series.
1991-08-20
wurking and counter electrodes, and a AgCl/Ag quasi-reference electrode with ferrocene (Fc) as an internal standard. The Fc+/Fc couple was assumed to...assigning the electronic spectra of these species. Similar work has been completed on phosphine substituted species which offer a wider range of
Wedemeyer, Gary A.; Nelson, Nancy C.
1975-01-01
Gaussian and nonparametric (percentile estimate and tolerance interval) statistical methods were used to estimate normal ranges for blood chemistry (bicarbonate, bilirubin, calcium, hematocrit, hemoglobin, magnesium, mean cell hemoglobin concentration, osmolality, inorganic phosphorus, and pH for juvenile rainbow (Salmo gairdneri, Shasta strain) trout held under defined environmental conditions. The percentile estimate and Gaussian methods gave similar normal ranges, whereas the tolerance interval method gave consistently wider ranges for all blood variables except hemoglobin. If the underlying frequency distribution is unknown, the percentile estimate procedure would be the method of choice.
Current trends and future directions in flower development research
Scutt, Charlie P.; Vandenbussche, Michiel
2014-01-01
Flowers, the reproductive structures of the approximately 400 000 extant species of flowering plants, exist in a tremendous range of forms and sizes, mainly due to developmental differences involving the number, arrangement, size and form of the floral organs of which they consist. However, this tremendous diversity is underpinned by a surprisingly robust basic floral structure in which a central group of carpels forms on an axis of determinate growth, almost invariably surrounded by two successive zones containing stamens and perianth organs, respectively. Over the last 25 years, remarkable progress has been achieved in describing the molecular mechanisms that control almost all aspects of flower development, from the phase change that initiates flowering to the final production of fruits and seeds. However, this work has been performed almost exclusively in a small number of eudicot model species, chief among which is Arabidopsis thaliana. Studies of flower development must now be extended to a much wider phylogenetic range of flowering plants and, indeed, to their closest living relatives, the gymnosperms. Studies of further, more wide-ranging models should provide insights that, for various reasons, cannot be obtained by studying the major existing models alone. The use of further models should also help to explain how the first flowering plants evolved from an unknown, although presumably gymnosperm-like ancestor, and rapidly diversified to become the largest major plant group and to dominate the terrestrial flora. The benefits for society of a thorough understanding of flower development are self-evident, as human life depends to a large extent on flowering plants and on the fruits and seeds they produce. In this preface to the Special Issue, we introduce eleven articles on flower development, representing work in both established and further models, including gymnosperms. We also present some of our own views on current trends and future directions of the flower development field. PMID:25335868
Vertical Movement Patterns and Ontogenetic Niche Expansion in the Tiger Shark, Galeocerdo cuvier
Afonso, André S.; Hazin, Fábio H. V.
2015-01-01
Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (< 5 m) waters but variability in depth usage was observed as some sharks used mostly shallow (< 60 m) waters whereas others made frequent incursions into greater depths. A diel behavioral shift was detected, with sharks spending considerably more time in surface (< 10 m) waters during the night. Moreover, a clear ontogenetic expansion in the vertical range of tiger shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche. PMID:25629732
NASA Astrophysics Data System (ADS)
Cantoni, Elena; Apel, W. D.; Arteaga-Velázquez, J. C.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz, P.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Link, K.; Łuczak, P.; Ludwig, M.; Mathes, H. J.; Mayer, H. J.; Melissas, M.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.
2011-03-01
The KASCADE-Grande experiment operates at Karlsruhe Institute of Technology (KIT) in Germany. It's aim is the study of the primary cosmic radiation, through Extensive Air Shower detection, in the range 1016-1018 eV. Here, measurements are of main interest to understand the high energy evolution of cosmic radiation: a change in the slope of the heavy primary spectrum is expected (as measured at lower energies for lighter primaries) as a possible confirmation of the predicted astrophysical mechanisms; moreover, in this range the transition from galactic to extragalactic radiation is supposed to take place and the observations could clarify the features of this transition, putting the basis for the interpretation of the data at the highest energies. For these tasks KASCADE-Grande fulfills very well the requirements, both concerning the acceptance and the experimental performances. The experiment is constituted by two co-operating arrays of detectors: the KASCADE array, with its 252 detectors in a dense grid of 200×200 m2 and the Grande array, made of 37 detectors arranged on a wider area of 700×700 m2. The Grande array samples the total charged particles size of the air shower, while the KASCADE array provides the muon size In this contribution, KASCADE-Grande measurement of the cosmic ray primary energy spectrum is presented. The exploited technique, calibrated with simulations, combines the charged particles component and muon component on a shower by shower basis, performing the energy estimation of each primary event. Other techniques are also performed, for a better evaluation of systematics and a check of consistency of the hadronic interaction model used in simulations.
Vertical movement patterns and ontogenetic niche expansion in the tiger shark, Galeocerdo cuvier.
Afonso, André S; Hazin, Fábio H V
2015-01-01
Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (< 5 m) waters but variability in depth usage was observed as some sharks used mostly shallow (< 60 m) waters whereas others made frequent incursions into greater depths. A diel behavioral shift was detected, with sharks spending considerably more time in surface (< 10 m) waters during the night. Moreover, a clear ontogenetic expansion in the vertical range of tiger shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche.
Veremchuk, Lyudmila V; Tsarouhas, Konstantinos; Vitkina, Tatyana I; Mineeva, Elena E; Gvozdenko, Tatyana A; Antonyuk, Marina V; Rakitskii, Valeri N; Sidletskaya, Karolina A; Tsatsakis, Aristidis M; Golokhvast, Kirill S
2018-04-01
Environmental pollution, local climatic conditions and their association with the prevalence and exacerbation of asthma are topics of intense current medical investigation. Air pollution in the area of Vladivostock was estimated both by the index of emission volumes of "air gaseous components" (nitrogen oxide and nitrogen dioxide, formaldehyde, hydrogen sulfide, carbon monoxide) in urban atmosphere and by mass spectrometric analysis of precipitates in snow samples. A total of 172 local asthma patients (101 controlled-asthma patients-CAP and 71 non-controlled asthma patients - nCAP) were evaluated with the use of spirometry and body plethysmography. Airway obstruction reversibility was evaluated with the use of an inhaled bronchodilator. Using discriminant analysis the association of environmental parameters with clinical indices of asthma patients is explored and thresholds of impact are established. CAP presented high sensitivity to large-size suspended air particles and to several of the studied climatic parameters. Discriminant analysis showed high values of Wilks' lambda index (α = 0.69-0.81), which implies limited influence of environmental factors on the respiratory parameters of CAP. nCAP were more sensitive and susceptible to the majority of the environmental factors studied, including air suspended toxic metals particles (Cr, Zn and Ni). Air suspended particles showed higher tendency for pathogenicity in nCAP population than in the CAP, with a wider range of particle sizes being involved. Dust fractions ranging from 0 to 1 μm and from 50 to 100 μm were additionally implicated compared to CAP group. Considerably lowest thresholds levels of impact are calculated for nCAP. Copyright © 2017. Published by Elsevier Ltd.
The combination of electrospray and flow focusing
NASA Astrophysics Data System (ADS)
Gañán-Calvo, Alfonso M.; López-Herrera, José M.; Riesco-Chueca, Pascual
2006-11-01
An ultra-fine liquid atomization procedure combining the advantages of electrospray and flow focusing is presented. Both techniques are known to produce strikingly small and steady liquid micro-jets issuing from menisci held by capillary forces. Such menisci take the form of a cusp-like drop attached to the feeding tube (flow focusing: FF) or a Taylor cone (electrospray: ES). The issuing micro-jets are forced or ‘sucked’ from the parent meniscus either by pressure or electrohydrodynamic forces. Subsequent capillary breakup of the jet leads to fine sprays of remarkable quality. Here we describe the joint effect of pressurization and electrification in a flow focusing device, and the subsequent coupling of both ES and FF phenomena. For any given liquid and flow rate, the combined procedure gives rise to significantly smaller droplet sizes than observed in any of the source techniques. The co-flowing gas stream removes space charges; in addition, the perforated plate facing the feed tube provides an electric barrier, shielding the jet-meniscus or ‘production’ area from the spray or ‘product’ area. As a result, space charges and electrified droplets are removed from the production area, thus avoiding the ambient electric saturation which becomes a limiting factor in ES-spraying: a significantly enhanced spraying stability ensues, with a much wider operation range than FF or ES. Other unexpected outcomes from the combination are also shown. A theoretical model is developed to predict the emitted droplet size: a first integral of the momentum equation yielding a generalized Bernoulli equation, and an explicit approximation for the jet diameter and droplet size, accurate within a broad parametrical band.
NASA Astrophysics Data System (ADS)
Zhang, Haichong K.; Aalamifar, Fereshteh; Boctor, Emad M.
2016-04-01
Synthetic aperture for ultrasound is a technique utilizing a wide aperture in both transmit and receive to enhance the ultrasound image quality. The limitation of synthetic aperture is the maximum available aperture size limit determined by the physical size of ultrasound probe. We propose Synthetic-Tracked Aperture Ultrasound (STRATUS) imaging system to overcome the limitation by extending the beamforming aperture size through ultrasound probe tracking. With a setup involving a robotic arm, the ultrasound probe is moved using the robotic arm, while the positions on a scanning trajectory are tracked in real-time. Data from each pose are synthesized to construct a high resolution image. In previous studies, we have demonstrated the feasibility through phantom experiments. However, various additional factors such as real-time data collection or motion artifacts should be taken into account when the in vivo target becomes the subject. In this work, we build a robot-based STRATUS imaging system with continuous data collection capability considering the practical implementation. A curvilinear array is used instead of a linear array to benefit from its wider capture angle. We scanned human forearms under two scenarios: one submerged the arm in the water tank under 10 cm depth, and the other directly scanned the arm from the surface. The image contrast improved 5.51 dB, and 9.96 dB for the underwater scan and the direct scan, respectively. The result indicates the practical feasibility of STRATUS imaging system, and the technique can be potentially applied to the wide range of human body.
Dobres, Jonathan; Wolfe, Benjamin; Chahine, Nadine; Reimer, Bryan
2018-07-01
Reading at a glance, once a relatively infrequent mode of reading, is becoming common. Mobile interaction paradigms increasingly dominate the way in which users obtain information about the world, which often requires reading at a glance, whether from a smartphone, wearable device, or in-vehicle interface. Recent research in these areas has shown that a number of factors can affect text legibility when words are briefly presented in isolation. Here we expand upon this work by examining how legibility is affected by more crowded presentations. Word arrays were combined with a lexical decision task, in which the size of the text elements and the inter-line spacing (leading) between individual items were manipulated to gauge their relative impacts on text legibility. In addition, a single-word presentation condition that randomized the location of presentation was compared with previous work that held position constant. Results show that larger text was more legible than smaller text. Wider leading significantly enhanced legibility as well, but contrary to expectations, wider leading did not fully counteract decrements in legibility at smaller text sizes. Single-word stimuli presented with random positioning were more difficult to read than stationary counterparts from earlier studies. Finally, crowded displays required much greater processing time compared to single-word displays. These results have implications for modern interface design, which often present interactions in the form of scrollable and/or selectable lists. The present findings are of practical interest to the wide community of graphic designers and interface engineers responsible for developing our interfaces of daily use. Copyright © 2018 Elsevier Ltd. All rights reserved.
Leroux, Robin A; Dutton, Peter H; Abreu-Grobois, F Alberto; Lagueux, Cynthia J; Campbell, Cathi L; Delcroix, Eric; Chevalier, Johan; Horrocks, Julia A; Hillis-Starr, Zandy; Troëng, Sebastian; Harrison, Emma; Stapleton, Seth
2012-01-01
Management of the critically endangered hawksbill turtle in the Wider Caribbean (WC) has been hampered by knowledge gaps regarding stock structure. We carried out a comprehensive stock structure re-assessment of 11 WC hawksbill rookeries using longer mtDNA sequences, larger sample sizes (N = 647), and additional rookeries compared to previous surveys. Additional variation detected by 740 bp sequences between populations allowed us to differentiate populations such as Barbados-Windward and Guadeloupe (F (st) = 0.683, P < 0.05) that appeared genetically indistinguishable based on shorter 380 bp sequences. POWSIM analysis showed that longer sequences improved power to detect population structure and that when N < 30, increasing the variation detected was as effective in increasing power as increasing sample size. Geographic patterns of genetic variation suggest a model of periodic long-distance colonization coupled with region-wide dispersal and subsequent secondary contact within the WC. Mismatch analysis results for individual clades suggest a general population expansion in the WC following a historic bottleneck about 100 000-300 000 years ago. We estimated an effective female population size (N (ef)) of 6000-9000 for the WC, similar to the current estimated numbers of breeding females, highlighting the importance of these regional rookeries to maintaining genetic diversity in hawksbills. Our results provide a basis for standardizing future work to 740 bp sequence reads and establish a more complete baseline for determining stock boundaries in this migratory marine species. Finally, our findings illustrate the value of maintaining an archive of specimens for re-analysis as new markers become available.
NASA Astrophysics Data System (ADS)
Grueger, Heinrich; Schenk, Harald; Heberer, Andreas; Zimmer, Fabian; Scherff, Werner; Kenda, Andreas; Frank, Albert
2005-11-01
Further optimization of the agricultural growth process and quality control of perishable food which can be fruits and vegetables as well as every kind of meat or milk product requires new approaches for the sensitive front end. One possibility is reflectance or fluorescence spectroscopy in a wide wavelength range. By now broad usage is hindered by costs, size and performance of existing systems. MOEMS scanning gratings for spectrometers and translational mirrors for Fourier Transform spectroscopy enable small robust systems working in a range from 200nm to 5μm. Both types use digital signal processors (DSPs) capable to compute the spectra and execute complex evaluation and decision algorithms. The MOEMS chips are realized by anisotropic etching of a silicon on insulator (SOI) substrate. First the backside silicon and buried oxide is removed by a wet process then the front side structure is realized by dry etching. Depending on the bearing springs a silicon plate up to 3 x 3 mm2 wide and typically 30μm thick can be driven resonantly to rotational or translational movement. Combined with additional optical components and appropriate detectors handheld Czerny-Turner or Fourier Transform spectrometers have been realized and tested. Results of first measurements of reflection spectroscopy on model substances have been performed with both system types in the NIR range. Measurements on real objects like tomatoes or apples are intended for a wider wavelength range. Future systems may contain displays and light sources as well as data storage cards or additional interfaces.
Xiao, Ruiyang; Zammit, Ian; Wei, Zongsu; Hu, Wei-Ping; MacLeod, Matthew; Spinney, Richard
2015-11-17
The ubiquitous presence of cyclic volatile methylsiloxanes (cVMS) in the global atmosphere has recently raised environmental concern. In order to assess the persistence and long-range transport potential of cVMS, their second-order rate constants (k) for reactions with hydroxyl radical ((•)OH) in the gas phase are needed. We experimentally and theoretically investigated the kinetics and mechanism of (•)OH oxidation of a series of cVMS, hexamethylcyclotrisiloxane (D3), octamethycyclotetrasiloxane (D4), and decamethycyclopentasiloxane (D5). Experimentally, we measured k values for D3, D4, and D5 with (•)OH in a gas-phase reaction chamber. The Arrhenius activation energies for these reactions in the temperature range from 313 to 353 K were small (-2.92 to 0.79 kcal·mol(-1)), indicating a weak temperature dependence. We also calculated the thermodynamic and kinetic behaviors for reactions at the M06-2X/6-311++G**//M06-2X/6-31+G** level of theory over a wider temperature range of 238-358 K that encompasses temperatures in the troposphere. The calculated Arrhenius activation energies range from -2.71 to -1.64 kcal·mol(-1), also exhibiting weak temperature dependence. The measured k values were approximately an order of magnitude higher than the theoretical values but have the same trend with increasing size of the siloxane ring. The calculated energy barriers for H-atom abstraction at different positions were similar, which provides theoretical support for extrapolating k for other cyclic siloxanes from the number of abstractable hydrogens.
Yamada, Akira; Terakawa, Mitsuhiro
2015-04-10
We present a design method of a bull's eye structure with asymmetric grooves for focusing oblique incident light. The design method is capable of designing transmission peaks to a desired oblique angle with capability of collecting light from a wider range of angles. The bull's eye groove geometry for oblique incidence is designed based on the electric field intensity pattern around an isolated subwavelength aperture on a thin gold film at oblique incidence, calculated by the finite difference time domain method. Wide angular transmission efficiency is successfully achieved by overlapping two different bull's eye groove patterns designed with different peak angles. Our novel design method would overcome the angular limitations of the conventional methods.
Remuneration discrepancies in the landlocked economies of Malaŵi and Uganda.
Munthali, Alister; Matagi, Leon; Tumwebaze, Callist
2010-10-01
Although the original study of remuneration differences between local and expatriate development workers took place in the landlocked economy of Malaŵi, the study has never been replicated outside of one sector and organization (the National University), and took place prior to the 2000 Millennium Development Goals. Participating in the present studies were 458 aid and development professionals, working across a range of sectors in Malaŵi (n = 241, response rate = 50%) and Uganda (n = 217, response rate = 51%). The size of the gap between local and international workers, measured using the World Bank's purchasing power parity, was higher in Malaŵi (4.04:1) than in Uganda (1.97:1). The ratio was more clearly within tolerance levels in Uganda than in Malaŵi. Consistent with these differences, and controlling for organization, cultural, and demographic factors, locally remunerated workers reported more and expatriate workers less injustice and demotivation in Malaŵi than in Uganda. Although sample sizes for the internationally remunerated are small, the findings suggest that wider disparities may (1) hinder perspective-taking and (2) decrease motivation. In-country workshops with stakeholders and subject-matter experts considered the findings, and potential solutions offered through the survey form. They recommended the implementation of performance-based remuneration, including competency-based job analysis and evaluation. Competencies in such functions can be provided by humanitarian work psychology.
A Bayesian bird's eye view of ‘Replications of important results in social psychology’
Schönbrodt, Felix D.; Yao, Yuling; Gelman, Andrew; Wagenmakers, Eric-Jan
2017-01-01
We applied three Bayesian methods to reanalyse the preregistered contributions to the Social Psychology special issue ‘Replications of Important Results in Social Psychology’ (Nosek & Lakens. 2014 Registered reports: a method to increase the credibility of published results. Soc. Psychol. 45, 137–141. (doi:10.1027/1864-9335/a000192)). First, individual-experiment Bayesian parameter estimation revealed that for directed effect size measures, only three out of 44 central 95% credible intervals did not overlap with zero and fell in the expected direction. For undirected effect size measures, only four out of 59 credible intervals contained values greater than 0.10 (10% of variance explained) and only 19 intervals contained values larger than 0.05. Second, a Bayesian random-effects meta-analysis for all 38 t-tests showed that only one out of the 38 hierarchically estimated credible intervals did not overlap with zero and fell in the expected direction. Third, a Bayes factor hypothesis test was used to quantify the evidence for the null hypothesis against a default one-sided alternative. Only seven out of 60 Bayes factors indicated non-anecdotal support in favour of the alternative hypothesis (BF10>3), whereas 51 Bayes factors indicated at least some support for the null hypothesis. We hope that future analyses of replication success will embrace a more inclusive statistical approach by adopting a wider range of complementary techniques. PMID:28280547
Molecular Evidence for Species-Level Distinctions in Clouded Leopards
Buckley-Beason, Valerie A.; Johnson, Warren E.; Nash, Willliam G.; Stanyon, Roscoe; Menninger, Joan C.; Driscoll, Carlos A.; Howard, JoGayle; Bush, Mitch; Page, John E.; Roelke, Melody E.; Stone, Gary; Martelli, Paolo P.; Wen, Ci; Ling, Lin; Duraisingam, Ratna K.; Lam, Phan V.
2017-01-01
Summary Among the 37 living species of Felidae, the clouded leopard (Neofelis nebulosa) is generally classified as a monotypic genus basal to the Panthera lineage of great cats [1–5]. This secretive, mid-sized (16–23 kg) carnivore, now severely endangered, is traditionally subdivided into four southeast Asian subspecies (Figure 1A) [4–8]. We used molecular genetic methods to re-evaluate subspecies partitions and to quantify patterns of population genetic variation among 109 clouded leopards of known geographic origin (Figure 1A, Tables S1 and S2 in the Supplemental Data available online). We found strong phylogeographic monophyly and large genetic distances between N. n. nebulosa (mainland) and N. n. diardi (Borneo; n = 3 individuals) with mtDNA (771 bp), nuclear DNA (3100 bp), and 51 microsatellite loci. Thirty-six fixed mitochondrial and nuclear nucleotide differences and 20 microsatellite loci with nonoverlapping allele-size ranges distinguished N. n. nebulosa from N. n. diardi. Along with fixed subspecies-specific chromosomal differences, this degree of differentiation is equivalent to, or greater than, comparable measures among five recognized Panthera species (lion, tiger, leopard, jaguar, and snow leopard). These distinctions increase the urgency of clouded leopard conservation efforts, and if affirmed by morphological analysis and wider sampling of N. n. diardi in Borneo and Sumatra, would support reclassification of N. n. diardi as a new species (Neofelis diardi). PMID:17141620
Bhowmik, Biplab; Bandyopadhyay, P K
2017-03-01
During the course of a biodiversity survey of the endoparasitic aseptate gregarines in the Malda district of West Bengal, India, seminal vesicles of the earthworm, Eutyphoeus kherai , Julka 1978 were found to be infested with a new species, Monocystis julkae sp.nov., of the genus, Monocystis Stein (Arch Anat Phys Med 181-223, 1848). The trophozoite is elongated but slightly constricted posteriorly. A tail like protrusion appears in the posterior end. Anterior end is rather wider than the posterior one. The whole body size of the trophozoite measures 102.2-184.0 (126.7 ± 19.9) µm × 40.9-81.8 (58.2 ± 10.0) µm. Size of the nucleus ranges from 10.2 to 16.3 (11.9 ± 1.9) µm × 8.1-12.2 (8.8 ± 1.2) µm. The gametocysts are ovoidal containing two unequal gametocytes. Diameter of it measures 61.3-98.1 (75.8 ± 8.6) µm. Oocysts are navicular and measures 6.9-10.0 (8.7 ± 0.9) µm × 3.0-4.6 (4.3 ± 0.4) µm.
Murphy, Philip N; Bruno, Raimondo; Ryland, Ida; Wareing, Michele; Fisk, John E; Montgomery, Catharine; Hilton, Joanne
2012-03-01
To review, with meta-analyses where appropriate, performance differences between ecstasy (3,4-methylenedioxymethamphetamine) users and non-users on a wider range of visuospatial tasks than previously reviewed. Such tasks have been shown to draw upon working memory executive resources. Abstract databases were searched using the United Kingdom National Health Service Evidence Health Information Resource. Inclusion criteria were publication in English language peer-reviewed journals and the reporting of new findings regarding human ecstasy-users' performance on visuospatial tasks. Data extracted included specific task requirements to provide a basis for meta-analyses for categories of tasks with similar requirements. Fifty-two studies were identified for review, although not all were suitable for meta-analysis. Significant weighted mean effect sizes indicating poorer performance by ecstasy users compared with matched controls were found for tasks requiring recall of spatial stimulus elements, recognition of figures and production/reproduction of figures. There was no evidence of a linear relationship between estimated ecstasy consumption and effect sizes. Given the networked nature of processing for spatial and non-spatial visual information, future scanning and imaging studies should focus on brain activation differences between ecstasy users and non-users in the context of specific tasks to facilitate identification of loci of potentially compromised activity in users. Copyright © 2012 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nakano, Yuriko; Ochiai, Asumi; Kawamoto, Keisuke
To understand the competing effects of the components in extracellular substances (ES), polymeric substances (PS) and low-molecular-weight small substances (SS) <1 kDa derived from microorganisms, on the colloidal stability of cerium dioxide nanoparticles (CeNPs), we investigated their adsorption to sparingly soluble CeNPs at room temperature at pH 6.0. The ES was extracted from the fungus S. cerevisiae. The polypeptides and phosphates in all components preferentially adsorbed onto the CeNPs. The zeta potentials of ES + CeNPs, PS + CeNPs, and SS + CeNPs overlapped on the plot of PS itself, indicating the surface charge of the polymeric substances controls themore » zeta potentials. The sizes of the CeNP aggregates, 100–1300 nm, were constrained by the zeta potentials. The steric barrier derived from the polymers, even in SS, enhanced the CeNP dispersibility at pH 1.5–10. Consequently, the PS and SS had similar effects on modifying the CeNP surfaces. The adsorption of ES, which contains PS + SS, can suppress the aggregation of CeNPs over a wider pH range than that for PS only. The present study addresses the non-negligible effects of small-sized molecules derived from microbial activity on the migration of CeNP in aquatic environments, especially where bacterial consortia prevail.« less
Biographies of Exclusion: Poor Work and Poor Transitions
ERIC Educational Resources Information Center
Shildrick, Tracy; MacDonald, Robert
2007-01-01
The usefulness of the concept of transition has been hotly contested in Anglophone youth studies over the past decade. A variety of criticisms have been ranged against it, including that it: presumes the continuing predominance of linear, obvious, mainstream pathways to adulthood; excludes wider youth questions in focusing narrowly on educational…
Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...
Parents Guide on Choice. The Right To Choose.
ERIC Educational Resources Information Center
Raywid, Mary Anne
Starting with the contention that we need to restore a wider range of choice to parents in their children's education, this paper lists and reviews the varieties of public education currently available throughout the country, and discusses their advantages and disadvantages. These varieties include magnet schools, alternative schools, independent…
Response Strength in Extreme Multiple Schedules
ERIC Educational Resources Information Center
McLean, Anthony P.; Grace, Randolph C.; Nevin, John A.
2012-01-01
Four pigeons were trained in a series of two-component multiple schedules. Reinforcers were scheduled with random-interval schedules. The ratio of arranged reinforcer rates in the two components was varied over 4 log units, a much wider range than previously studied. When performance appeared stable, prefeeding tests were conducted to assess…
Aging: Prospects and Issues. Revised. 1976.
ERIC Educational Resources Information Center
Davis, Richard H., Ed.
Completely revised and updated since its first edition in 1973, the book explores an even wider range of concerns regarding gerontology. Part 1 presents an overview of the multiple aspects of gerontology, and includes the following chapters: (1) Aging: Prospects and Issues, Richard H. Davis; (2) Aging: The Psychologist's Perspective, James E.…
Heavy Metal Music and Reckless Behavior among Adolescents.
ERIC Educational Resources Information Center
Arnett, Jeffrey
1991-01-01
Fifty-four male and 30 female adolescents who like heavy metal music were compared on various outcome variables to 56 male and 105 female peers who do not like it. Those who like heavy metal report a wider range of reckless behavior than those who do not like it. (SLD)
Alternative Instructional Strategies in an IS Curriculum
ERIC Educational Resources Information Center
Parker, Kevin R.; LeRouge, Cynthia; Trimmer, Ken
2005-01-01
Systems Analysis and Design is a core component of an education in information systems. To appeal to a wider range of constituents and facilitate the learning process, the content of a traditional Systems Analysis and Design course has been supplemented with an alternative modeling approach. This paper presents an instructional design that…
Culture vs. Technology: Mass Media Policy of the Netherlands Attempts a Balance.
ERIC Educational Resources Information Center
Heuterman, Thomas H.; Rennen, Toon
Telecommunications policy makers in Western Europe face the dilema of satisfying public demand for a wider range of television viewing alternatives without sacrificing national cultural integrity. The Dutch Parliament addressed this problem in 1984, 1985, and 1986 as it approved steps to implement the "Medianota," the comprehensive…
Arginase: A Novel Proliferative Determinant in Prostate Cancer
2005-04-01
neoplastic prostate samples. The purpose of the present research funded by USAMRMC is to examine the expression of All in a wider range of benign and - malignant prostate...of polyamine synthesis levels in these lines, and our measurement and localization of arginase expression in benign and malignant prostate tissue samples.
Understanding Online Knowledge Sharing: An Interpersonal Relationship Perspective
ERIC Educational Resources Information Center
Ma, Will W. K.; Yuen, Allan H. K.
2011-01-01
The unique features and capabilities of online learning are built on the ability to connect to a wider range of learning resources and peer learners that benefit individual learners, such as through discussion forums, collaborative learning, and community building. The success of online learning thus depends on the participation, engagement, and…
Operations Management and Curriculum Design.
ERIC Educational Resources Information Center
Slack, Nigel
1983-01-01
The last few years have seen developments in the academic treatment of operations management which both broaden the subject to include a much wider range of industries in the nonmanufacturing sectors and place the operations function in a more strategic context. (MEAD Subscriptions, CSML, University of Lancaster, Lancaster LA1 4YX, England) (SSH)
Documenting Variation in (Endangered) Heritage Languages: How and Why?
ERIC Educational Resources Information Center
Nagy, Naomi
2017-01-01
This paper contributes to recently expanded interest in documenting variable as well as categorical patterns of endangered languages. It describes approaches, tools and curricular developments that have benefitted from involving students who are heritage language community members, key to expanding variationist focus to a wider range of languages.…
Assessment Using Multi-Criteria Decision Approach for "Higher Order Skills" Learning Domains
ERIC Educational Resources Information Center
Ramakishnan, Sadhu Balasundaram; Ramadoss, Balakrishnan
2009-01-01
Over the past several decades, a wider range of assessment strategies has gained prominence in classrooms, including complex assessment items such as individual or group projects, student journals and other creative writing tasks, graphic/artistic representations of knowledge, clinical interviews, student presentations and performances, peer- and…
Levels of Student Responses in a Spreadsheet-Based Environment
ERIC Educational Resources Information Center
Tabach, Michal; Friedlander, Alex
2004-01-01
The purpose of this report is to investigate the range of student responses in three domains--hypothesizing, organizing data, and algebraic generalization of patterns during their work on a spreadsheet-based activity. In a wider context, we attempted to investigate students' utilization schemes of spreadsheets in their learning of introductory…
Promising Practices in Small High Schools. A Report of 15 Northwest Projects.
ERIC Educational Resources Information Center
Northwest Regional Educational Lab., Portland, OR.
Promising methods utilized in small rural high schools to provide a wider range of experiences for students are identified and described. Programs reported on include the Arctic Nursing Program, Career Research Program, Contractual Study Program, Eye-opening Experience, Field Experience Program, Guitar and Folk Music Program, Individualized…
A Wider Spectrum of Opportunities.
ERIC Educational Resources Information Center
Council for Industry and Higher Education (United Kingdom).
The United Kingdom must invest in a comprehensive system of post-18 education that is broadly inclusive and that offers a broad range of educational opportunities to meet the needs of both the increasing numbers of 16-year-olds choosing to pursue postsecondary education and the many older individuals needing additional education throughout their…
Persuading and Dissuading by Conditional Argument
ERIC Educational Resources Information Center
Thompson, V.A.; Evans, J.St.B.T.; Handley, S.J.
2005-01-01
Informal reasoning typically draws on a wider range of inferential behaviour than is measured by traditional inference tasks. In this paper, we developed several tasks to study informal reasoning with two novel types of conditional statements: Persuasions (e.g., if the Kyoto accord is ratified, greenhouse gas emissions will be reduced) and…
Bipolaris microstegii Minnis, Rossman, Kleczewki & S.L. Flory, sp. nov.
USDA-ARS?s Scientific Manuscript database
Many species of Bipolaris are significant pathogens of grasses. A new species of Bipolaris was isolated from Microstegium vimineum, an invasive plant in the USA. The fungus causes disease on Microstegium, but it also infects a wider range of hosts. Comparison of ITS and gpd sequence data to sequence...
Effect of salt and ethanol addition on zein-starch dough and bread quality
USDA-ARS?s Scientific Manuscript database
Development of viscoelastic doughs from non-wheat proteins allows for a wider range of gluten-free products. Littlework has been completed to describemechanisms of zein functionality in food systems. To identify factors responsible for dough development in zein–starchmixtures and their influence on ...
Numerical Simulations of Mechanical Erosion from below by Creep on Rate-State Faults
NASA Astrophysics Data System (ADS)
Werner, M. J.; Rubin, A. M.
2012-04-01
The aim of this study is to increase our understanding of how earthquakes nucleate on frictionally-locked fault patches that are loaded by the growing stress concentrations at their boundaries due to aseismic creep. Such mechanical erosion from below of locked patches has previously been invoked by Gillard et al. (1996) to explain accelerating seismicity and increases in maximum earthquake magnitude on a strike-slip streak (a narrow ribbon of tightly clustered seismicity) in Kilauea's East rift, and it might also play a role in the loading of major locked strike-slip faults by creep from below the seismogenic zone. Gillard et al. (1996) provided simple analytical estimates of the size of and moment release within the eroding edge of the locked zone that matched the observed seismicity in Kilauea's East rift. However, an obvious, similar signal has not consistently been found before major strike-slip earthquakes. Here, we use simulations to determine to what extent the simple estimates by Gillard et al. survive a wider range of geometric configurations and slip histories. The boundary between the locked and creeping sections at the base of the seismogenic zone is modeled as a gradual, continuous transition between steady-state velocity-strengthening at greater depth to velocity-weakening surroundings at shallow depth, qualitatively consistent with laboratory estimates of the temperature dependence of (a-b). The goal is to expand the range of possible outcomes to broaden our range of expectations for the behavior of the eroding edge of the locked zones.
Jones, S; Richardson, N; Bennett, M; Hoon, S R
2015-01-01
The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of atmospheric particulate matter (PM) on health and the environment. PM within the airport environment may be derived from a range of sources. To date, however, the identification of individual sources of airport derived PM has remained elusive but constitutes a research priority for the aviation industry.The aim of this research was to identify distinctive and characteristic fingerprints of atmospheric PM derived from various sources in an airport environment through the use of environmental magnetic measurements. PM samples from aircraft engine emissions, brake wear and tire wear residues have been obtained from a range of different aircraft and engine types. Samples have been analyzed utilizing a range of magnetic mineral properties indicative of magnetic mineralogy and grain size. Results indicate that the dusts from the three 'aircraft' sources, (i.e. engines, brakes and tires) display distinctive magnetic mineral characteristics which may serve as 'magnetic fingerprints' for these sources. Magnetic measurements of runway dusts collected at different locations on the runway surface also show contrasting magnetic characteristics which, when compared with those of the aircraft-derived samples, suggest that they may relate to different sources characteristic of aircraft emissions at various stages of the take-off/landing cycle. The findings suggest that magnetic measurements could have wider applicability for the differentiation and identification of PM within the airport environment.
NASA Astrophysics Data System (ADS)
Habtu, Solomon; Ludi, Eva; Jamin, Jean Yves; Oates, Naomi; Fissahaye Yohannes, Degol
2014-05-01
Practicing various innovations pertinent to irrigated farming at local field scale is instrumental to increase productivity and yield for small holder farmers in Africa. However the translation of innovations from local scale to the scale of a jointly operated irrigation scheme is far from trivial. It requires insight on the drivers for adoption of local innovations within the wider farmer communities. Participatory methods are expected to improve not only the acceptance of locally developed innovations within the wider farmer communities, but to allow also an estimation to which extend changes will occur within the entire irrigation scheme. On such a base, more realistic scenarios of future water productivity within an irrigation scheme, which is operated by small holder farmers, can be estimated. Initial participatory problem and innovation appraisal was conducted in Gumselassa small scale irrigation scheme, Ethiopia, from Feb 27 to March 3, 2012 as part of the EAU4FOOD project funded by EC. The objective was to identify and appraise problems which hinder sustainable water management to enhance production and productivity and to identify future research strategies. Workshops were conducted both at local (Community of Practices) and regional (Learning Practice Alliance) level. At local levels, intensive collaboration with farmers using participatory methods produced problem trees and a "Photo Safari" documented a range of problems that negatively impact on productive irrigated farming. A range of participatory methods were also used to identify local innovations. At regional level a Learning Platform was established that includes a wide range of stakeholders (technical experts from various government ministries, policy makers, farmers, extension agents, researchers). This stakeholder group did a range of exercise as well to identify major problems related to irrigated smallholder farming and already identified innovations. Both groups identified similar problems to productive smallholder irrigation: soil nutrient depletion, salinization, disease and pest resulting from inefficient irrigation practices, infrastructure problems leading to a reduction of the size of the command area and decrease in reservoir volume. The major causes have been poor irrigation infrastructure, poor on-farm soil and water management, prevalence of various crop pests and diseases, lack of inputs and reservoir siltation. On-farm participatory research focusing on soil, crop and water management issues, including technical, institutional and managerial aspects, to identify best performing innovations while taking care of the environment was recommended. Currently, a range of interlinked activities are implemented a multiple scales, combining participatory and scientific approaches towards innovation development and up-scaling of promising technologies and institutional and managerial approaches from local to regional scales. ____________________________ Key words: Irrigation scheme, productivity, innovation, participatory method, Gumselassa, Ethiopia
Effects of microrolling parameters on the microstructure and deformation behavior of pure copper
NASA Astrophysics Data System (ADS)
Jing, Yi; Zhang, Hong-mei; Wu, Hao; Li, Lian-jie; Jia, Hong-bin; Jiang, Zheng-yi
2018-01-01
Microrolling experiments and uniaxial tensile tests of pure copper under different annealing conditions were carried out in this paper. The effects of grain size and reduction on non-uniform deformation, edge cracking, and microstructure were studied. The experimental results showed that the side deformation became more non-uniform, resulting in substantial edge bulge, and the uneven spread increased with increasing grain size and reduction level. When the reduction level reached 80% and the grain size was 65 μm, slight edge cracks occurred. When the grain size was 200 μm, the edge cracks became wider and deeper. No edge cracks occurred when the grain size was 200 μm and the reduction level was less than 60%; edge cracks occurred when the reduction level was increased to 80%. As the reduction level increased, the grains were gradually elongated and appeared as a sheet-like structure along the rolling direction; a fine lamellar structure was obtained when the grain size was 20 μm and the reduction level was less than 60%.
Sexual dimorphism in the human face assessed by euclidean distance matrix analysis.
Ferrario, V F; Sforza, C; Pizzini, G; Vogel, G; Miani, A
1993-01-01
The form of any object can be viewed as a combination of size and shape. A recently proposed method (euclidean distance matrix analysis) can differentiate between size and shape differences. It has been applied to analyse the sexual dimorphism in facial form in a sample of 108 healthy young adults (57 men, 51 women). The face was wider and longer in men than in women. A global shape difference was demonstrated, the male face being more rectangular and the female face more square. Gender variations involved especially the lower third of the face and, in particular, the position of the pogonion relative to the other structures. PMID:8300436
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bishnoi, Dimple
In this paper, we demonstrate theoretically that the Quantum dots are quite interesting for the electronics industry. Semiconductor quantum dots (QDs) are nanometer-scale crystals, which have unique photo physical, quantum electrical properties, size-dependent optical properties, There small size means that electrons do not have to travel as far as with larger particles, thus electronic devices can operate faster. Cheaper than modern commercial solar cells while making use of a wider variety of photon energies, including “waste heat” from the sun’s energy. Quantum dots can be used in tandem cells, which are multi junction photovoltaic cells or in the intermediate bandmore » setup. PbSe (lead selenide) is commonly used in quantum dot solar cells.« less
Pore size engineering applied to the design of separators for nickel-hydrogen cells and batteries
NASA Technical Reports Server (NTRS)
Abbey, K. M.; Britton, D. L.
1983-01-01
Pore size engineering in starved alkaline multiplate cells involves adopting techniques to widen the volume tolerance of individual cells. Separators with appropriate pore size distributions and wettability characteristics (capillary pressure considerations) to have wider volume tolerances and an ability to resist dimensional changes in the electrodes were designed. The separators studied for potential use in nickel-hydrogen cells consist of polymeric membranes as well as inorganic microporous mats. In addition to standard measurements, the resistance and distribution of electrolyte as a function of total cell electrolyte content were determined. New composite separators consisting of fibers, particles and/or binders deposited on Zircar cloth were developed in order to engineer the proper capillary pressure characteristics in the separator. These asymmetric separators were prepared from a variety of fibers, particles and binders.
Study of TiO2 particles size, dyes, and catalyst to improve the performance of DSSC
NASA Astrophysics Data System (ADS)
Saehana, Sahrul; Darsikin, Muslimin
2016-02-01
This study reports effort to improve performance of solar cells by using various natural dyes in dye-sensitized solar cell (DSSC). We applied three kind of natural dye, i.e, black rice dye, cactus dye and dragon fruit dye. We found that performance of DSSC which employ black rice dye was higher than other natural dyes. It is because the wider spectrum wavelength of black rice dyes. Its performance also compared with rhutenium dye (N719). Effect of TiO2 particle to DSSC performance was also investigated. It was concluded that smaller TiO2 particle size will increase the performance of DSSC solar cells. It was because the smaller particle size (high surface area) will load more dye. In addition, we also demonstrated the use of graphite from lead pencil as counter electrode.
Lu, Chunsong; Liu, Yangang; Niu, Shengjie; ...
2017-10-12
In the paper of warm clouds, there are many outstanding questions. Cloud droplet size distributions are much wider, and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectations. This review summarizes the studies related to the effects of turbulent fluctuations and turbulent entrainment-mixing on the broadening of droplet size distributions and warm rain initiation, including observational, laboratorial, numerical, and theoretical achievements. Particular attention is paid to studies by Chinese scientists since the 1950s, since most results have been published in Chinese. The review reveals that high-resolution observations and simulations, and laboratory experimentsmore » are needed because knowledge of the detailed physical processes involved in the effects of turbulence and entrainment-mixing on cloud microphysics still remains elusive.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lu, Chunsong; Liu, Yangang; Niu, Shengjie
In the paper of warm clouds, there are many outstanding questions. Cloud droplet size distributions are much wider, and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectations. This review summarizes the studies related to the effects of turbulent fluctuations and turbulent entrainment-mixing on the broadening of droplet size distributions and warm rain initiation, including observational, laboratorial, numerical, and theoretical achievements. Particular attention is paid to studies by Chinese scientists since the 1950s, since most results have been published in Chinese. The review reveals that high-resolution observations and simulations, and laboratory experimentsmore » are needed because knowledge of the detailed physical processes involved in the effects of turbulence and entrainment-mixing on cloud microphysics still remains elusive.« less
NASA Astrophysics Data System (ADS)
Sun, Xingdong; Li, Lijia; Guo, Yue; Zhao, Hongwei; Zhang, Shizhong; Yu, Yang; Wu, Di; Liu, Hang; Yu, Miao; Shi, Dong; Liu, Zeyang; Zhou, Mingxing; Ren, Luquan; Fu, Lu
2018-03-01
The phenomenon that water in bone has important influences on mechanical properties of cortical bone has been known. However, the detail of the influence mechanism is not clear, especially in the component hierarchy. The main objective of this paper is to investigate the mechanical properties of deproteinization bone and cortical bone with different water content by nanoindentation experiments. The deproteinization bone is cortical bone removed organic component, and demineralization bone is cortical bone removed inorganic component. The experiments results showed that the elastic modulus and hardness all increased with the decreasing of water content in both cortical bone and deproteinization bone. However, variations of deproteinization bone were more significant than the normal one. Without organic component, the shape and size of inorganic component (hydroxyapatite particles) turned to irregular. The plastic energy of both cortical bone and deproteinization bone all decreased with the decreasing of water content and the variations range of deproteinization bone was wider than cortical bone. This research may give some deeply understanding for the studies of influence of water on mechanical properties of cortical bone.
Choi, Andrew; Seo, Kyoung Duck; Kim, Do Wan; Kim, Bum Chang; Kim, Dong Sung
2017-02-14
Complex microparticles (MPs) bearing unique characteristics such as well-tailored sizes, various morphologies, and multi-compartments have been attempted to be produced by many researchers in the past decades. However, a conventionally used method of fabricating MPs, emulsion polymerization, has a limitation in achieving the aforementioned characteristics and several approaches such as the microfluidics-assisted (droplet-based microfluidics and flow lithography-based microfluidics), electrohydrodynamics (EHD)-based, centrifugation-based, and template-based methods have been recently suggested to overcome this limitation. The outstanding features of complex MPs engineered through these suggested methods have provided new opportunities for MPs to be applied in a wider range of applications including cell carriers, drug delivery agents, active pigments for display, microsensors, interface stabilizers, and catalyst substrates. Overall, the engineered MPs expose their potential particularly in the field of biomedical engineering as the increased complexity in the engineered MPs fulfills well the requirements of the high-end applications. This review outlines the current trends of newly developed techniques used for engineered MPs fabrication and focuses on the current state of engineered MPs in biomedical applications.
Wellard, Lyndal; Havill, Michelle; Hughes, Clare; Watson, Wendy L; Chapman, Kathy
2015-12-01
To examine the association between energy cost and energy density of fast food products. Twenty Sydney outlets of the five largest fast food chains were surveyed four times. Price and kilojoule data were collected for all limited-time-only menu items (n=54) and a sample of standard items (n=67). Energy cost ($/kilojoule) and energy density (kilojoules/gram) of menu items were calculated. There was a significant inverse relationship between menu item energy density and energy cost (p<0.001). Salads had the highest energy cost, while value items, meals that included a dessert and family meals had the lowest. Fast food chains could provide a wider range of affordable, lower-energy foods, use proportional pricing of larger serve sizes, or change defaults in meals to healthier options. More research is required to determine the most effective strategy to reduce the negative impact of fast food on the population's diet. Current pricing in the fast food environment may encourage unhealthier purchases. © 2015 Public Health Association of Australia.
Robotic Assisted Transanal Polypectomies: Is There Any Indication?
Gómez Ruiz, Marcos; Cagigas Fernández, Carmen; Alonso Martín, Joaquín; Cristobal Poch, Lidia; Manuel Palazuelos, Carlos; Barredo Cañibano, Francisco Javier; Gómez Fleitas, Manuel; Castillo Diego, Julio
2017-12-01
Robotic assisted transanal polipectomy may have advantages compared with the conventional transanal minimally invasive surgery technique. We evaluate the safety, feasibility and advantages of this technique. Between February 2014 and October 2015, 9patients underwent robotic transanal polypectomy. We performed a retrospective study in which we analyse prospectively collected data regarding patient and tumor characteristics, perioperative outcomes, pathological report, morbidity and mortality. A total of 5 male and 4 female patients underwent robotic TAMIS. Lesions were 6,22cm from the anal verge. Mean size was 15,8cm 2 . All procedures were performed in the lithotomy position. Closure of the defect was performed in all cases. Mean blood loss was 39,8ml. Mean operative time was 71,9min. No severe postoperative complications or readmissions occured. Median hospital stay was 2,5 days. Robotic TAMIS is useful to treat complex rectal lesions. Our transanal platform allowed a wider range of movements of the robotic arms and to perform all procedures in the lithotomy position. Copyright © 2017 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.
Modeled and Observed Altitude Distributions of the Micrometeoroid Influx in Radar Detection
NASA Astrophysics Data System (ADS)
Swarnalingam, N.; Janches, D.; Plane, J. M. C.; Carrillo-Sánchez, J. D.; Sternovsky, Z.; Pokorny, P.; Nesvorny, D.
2017-12-01
The altitude distributions of the micrometeoroids are a representation of the radar response function of the incoming flux and thus can be utilized to calibrate radar measurements. These in turn, can be used to determine the rate of ablation and ionization of the meteoroids and ultimately the input flux. During the ablation process, electrons are created and subsequently these electrons produce backscatter signals when they encounter the transmitted signals from radar. In this work, we investigate the altitude distribution by exploring different sizes as well as the aspect sensitivity of the meteor head echoes. We apply an updated version of the Chemical Ablation Model (CABMOD), which includes results from laboratory simulation of meteor ablation for different metallic constituents. In particular, the updated version simulates the ablation of Na. It is observed in the updated version that electrons are produced to a wider altitude range with the peak production occurs at lower altitudes compared to the previous version. The results are compared to head echo meteor observations utilizing the Arecibo 430 MHz radar.
Li, Hong-jiao; He, Li-yun; Liu, Bao-yan
2015-06-01
The effective quality control in clinical practices is an effective guarantee for the authenticity and scientificity of the findings. The post-marketing reevaluation for traditional Chinese medicines (TCM) focuses on the efficacy, adverse reaction, combined medication and effective dose of drugs in the market by expanded clinical trials, and requires a larger sample size and a wider range of patients. Therefore, this increases the difficulty of quality control in clinical practices. With the experience in quality control in clinical practices for the post-marketing reevaluation for Kangbingdu oral for cold, researchers in this study reviewed the study purpose, project, scheme design and clinical practice process from an overall point of view, analyzed the study characteristics of the post-marketing reevaluation for TCMs and the quality control risks, designed the quality control contents with quality impacting factors, defined key review contents and summarized the precautions in clinical practices, with the aim to improve the efficiency of quality control of clinical practices. This study can provide reference to clinical units and quality control-related personnel in the post-marketing reevaluation for TCMs.
Diversity of dsDNA Viruses in a South African Hot Spring Assessed by Metagenomics and Microscopy.
Zablocki, Olivier; van Zyl, Leonardo Joaquim; Kirby, Bronwyn; Trindade, Marla
2017-11-18
The current view of virus diversity in terrestrial hot springs is limited to a few sampling sites. To expand our current understanding of hot spring viral community diversity, this study aimed to investigate the first African hot spring (Brandvlei hot spring; 60 °C, pH 5.7) by means of electron microscopy and sequencing of the virus fraction. Microscopy analysis revealed a mixture of regular- and 'jumbo'-sized tailed morphotypes ( Caudovirales ), lemon-shaped virions ( Fuselloviridae- like; salterprovirus-like) and pleiomorphic virus-like particles. Metavirome analysis corroborated the presence of His1-like viruses and has expanded the current clade of salterproviruses using a polymerase B gene phylogeny. The most represented viral contig was to a cyanophage genome fragment, which may underline basic ecosystem functioning provided by these viruses. Furthermore, a putative Gemmata -related phage was assembled with high coverage, a previously undocumented phage-host association. This study demonstrated that a moderately thermophilic spring environment contained a highly novel pool of viruses and should encourage future characterization of a wider temperature range of hot springs throughout the world.
Kupetz, M; Sacher, B; Becker, T
2016-06-05
Structural polymers such as cereal β-glucan may cause various processing problems in beverage industry depending on concentration, molar size distribution and agglomeration behaviour. In this context, influences of the beer volatiles dodecanoic acid, octyl butanoate, ethyl decanoate and decyl acetate on molar mass and radii of barley β-glucan were investigated in ethanolic (4% w/w) model solution. After addition of 100mg/l ethyl decanoate and decyl acetate to the β-glucan solution, a wider-ranging molar mass distribution could be observed by means of asymmetric field-flow-fractionation. Due to agglomeration, average molar mass of β-glucan standard (MW=6.8×10(6)g/mol) increased by 2×10(6)g/mol (P<0.05) in solution containing decyl acetate. Furthermore, a significant growth (P<0.05) from 86 to 102 nm in gyration radius was measured. The obtained results elucidate the importance of fatty acid derived flavouring substance composition in beer regarding the aggregation behaviour of β-glucan. Copyright © 2016 Elsevier Ltd. All rights reserved.
Borlase, Jeanette; Abelson-Mitchell, Nadine
2008-01-01
The concern of academics and clinicians about the alleged dichotomy between theoretical concepts and the practice of nursing has been the catalyst for the development of a pocket-sized aid for nurses, known as the Knowledge Underpinning Practice Orientation Dial (KUPOD [N]/The Dial). A mixed method approach was used incorporating a questionnaire and a focus group of educators. The Dial was introduced, as part of a module, undertaken by a cohort of second-year Diploma in Nursing (Adult Branch) students. Twenty-eight students returned the questionnaire (response rate=85%). Results revealed that the Dial was easy to use in a variety of situations and locations. Respondents used the Dial within clinical and classroom settings and for self directed study. They reported that it was a practical and effective aid to learning, assisting in correlating theory and practice. It supported reflection and enhanced confidence in the clinical area, indicating that this economically produced tool helps to bridge the theory-practice gap. The Dial is now being introduced as a learning resource to a wider range of students.
Keijsers, Joep G. S.; Poortinga, Ate; Riksen, Michel J. P. M.; Maroulis, Jerry
2014-01-01
Depending on the amount of aeolian sediment input and dune erosion, dune size and morphology change over time. Since coastal foredunes play an important role in the Dutch coastal defence, it is important to have good insight in the main factors that control these changes. In this paper the temporal variations in foredune erosion and accretion were studied in relation to proxies for aeolian transport potential and storminess using yearly elevation measurements from 1965 to 2012 for six sections of the Dutch coast. Longshore differences in the relative impacts of erosion and accretion were examined in relation to local beach width. The results show that temporal variability in foredune accretion and erosion is highest in narrow beach sections. Here, dune erosion alternates with accretion, with variability displaying strong correlations with yearly values of storminess (maximum sea levels). In wider beach sections, dune erosion is less frequent, with lower temporal variability and stronger correlations with time series of transport potential. In erosion dominated years, eroded volumes decrease from narrow to wider beaches. When accretion dominates, dune-volume changes are relatively constant alongshore. Dune erosion is therefore suggested to control spatial variability in dune-volume changes. On a scale of decades, the volume of foredunes tends to increase more on wider beaches. However, where widths exceed 200 to 300 m, this trend is no longer observed. PMID:24603812
Keijsers, Joep G S; Poortinga, Ate; Riksen, Michel J P M; Maroulis, Jerry
2014-01-01
Depending on the amount of aeolian sediment input and dune erosion, dune size and morphology change over time. Since coastal foredunes play an important role in the Dutch coastal defence, it is important to have good insight in the main factors that control these changes. In this paper the temporal variations in foredune erosion and accretion were studied in relation to proxies for aeolian transport potential and storminess using yearly elevation measurements from 1965 to 2012 for six sections of the Dutch coast. Longshore differences in the relative impacts of erosion and accretion were examined in relation to local beach width. The results show that temporal variability in foredune accretion and erosion is highest in narrow beach sections. Here, dune erosion alternates with accretion, with variability displaying strong correlations with yearly values of storminess (maximum sea levels). In wider beach sections, dune erosion is less frequent, with lower temporal variability and stronger correlations with time series of transport potential. In erosion dominated years, eroded volumes decrease from narrow to wider beaches. When accretion dominates, dune-volume changes are relatively constant alongshore. Dune erosion is therefore suggested to control spatial variability in dune-volume changes. On a scale of decades, the volume of foredunes tends to increase more on wider beaches. However, where widths exceed 200 to 300 m, this trend is no longer observed.
Warrener, Anna G.; Lewton, Kristi L.; Pontzer, Herman; Lieberman, Daniel E.
2015-01-01
The shape of the human female pelvis is thought to reflect an evolutionary trade-off between two competing demands: a pelvis wide enough to permit the birth of large-brained infants, and narrow enough for efficient bipedal locomotion. This trade-off, known as the obstetrical dilemma, is invoked to explain the relative difficulty of human childbirth and differences in locomotor performance between men and women. The basis for the obstetrical dilemma is a standard static biomechanical model that predicts wider pelves in females increase the metabolic cost of locomotion by decreasing the effective mechanical advantage of the hip abductor muscles for pelvic stabilization during the single-leg support phase of walking and running, requiring these muscles to produce more force. Here we experimentally test this model against a more accurate dynamic model of hip abductor mechanics in men and women. The results show that pelvic width does not predict hip abductor mechanics or locomotor cost in either women or men, and that women and men are equally efficient at both walking and running. Since a wider birth canal does not increase a woman’s locomotor cost, and because selection for successful birthing must be strong, other factors affecting maternal pelvic and fetal size should be investigated in order to help explain the prevalence of birth complications caused by a neonate too large to fit through the birth canal. PMID:25760381
Adaptive Optics for Turbulent Shear Layers
2006-12-20
which is related to the phase variance through the wave number). Once obtained 5 by whatever means, the phase variance was used to compute an...new inlet for a wider test section and included a downstream throat to chock the flow and prevent pressure disturbances from the vacuum pumps from...wavefronts in Figure 15 are for an aperture size that captures only about half a cycle; the streamnwise length of the half cycle being -- 10 cm ( 4 in
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khan, Samreen Heena, E-mail: samreen.heena.khan@gmail.com; Suriyaprabha, R.; Pathak, Bhawana, E-mail: bhawana.pathak@cug.ac.in
With the miniaturization of crystal size, the fraction of under-coordinated surface atoms becomes dominant, and hence, materials in the nano-regime behave very differently from the similar material in a bulk. Zinc oxide (ZnO), particularly, exhibits extraordinary properties such as a wide direct band gap (3.37 eV), large excitation binding energy (60 meV), low refractive index (1.9), stability to intense ultraviolet (UV) illumination, resistance to high-energy irradiation, and lower toxicity as compared to other semiconductors. This very property makes Zinc Oxide a potential candidate in many application fields, particularly as a prominent semiconductor. Zinc Oxide plays a significant role in manymore » technological advances with its application in semiconductor mediated photocatalytic processes and sensor, solar cells and others. In present study, Zinc Oxide (ZnO) has been synthesized using three different precursors by sonochemical method. Zinc Acetate Dihydrate, Zinc Nitrate Hexahydrate and Zinc Sulphate Heptahydrate used as a precursor for the synthesis process. The synthesized ZnO nanoparticle has been found under the range of ∼50 nm. Zinc oxide nanoparticles were characterized using different characterizing tools. The as-synthesized ZnO was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR) for the determination of functional group; Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy (SEM-EDS) for Morphology and elemental detection respectively, Transmission Electron Microscopy for Particle size distribution and morphology and X-Ray Diffraction (XRD) for the confirmation of crystal structure of the nanomaterial. The optical properties of the ZnO were examined by UV-VIS spectroscopy equipped with Diffuse Reflectance spectroscopy (DRS) confirmed the optical band gap of ZnO-3 around 3.23 eV resembles with the band gap of bulk ZnO (3.37eV). The TEM micrograph of the as-synthesized material showed perfectly spherical shaped nanoparticle under the size range of 50nm. The XRD data showed that the ZnO-3 which was synthesized using Zinc Nitrate Hexahydrate as precursor showed the hexagonal wurtzite crystal structure. The XRD data obtained were compared with the JCPDS standard data. The precursor Zinc Nitrate Hexahydrate (ZnO-3) showed the good yield, monodispersity and size of nanoparticle under the range of 50 nm. The ZnO nanoparticles synthesize using different precursor was found effective in order of ZnO-3, followed by ZnO-1 & ZnO-2. The Synthesized ZnO has wider application in environmental remediation and clean-up as a potential nano-catalyst.« less
Modeling and studying of white light emitting diodes based on CdS/ZnS spherical quantum dots
NASA Astrophysics Data System (ADS)
Hasanirokh, K.; Asgari, A.
2018-07-01
In this paper, we propose a quantum dot (QD) based white light emitting diode (WLED) structure to study theoretically the material gain and quantum efficiency of the system. We consider the spherical QDs with a II-VI semiconductor core (CdS) that covered with a wider band gap semiconductor acting as a shell (ZnS). In order to generate white light spectrum, we use layers with different dot size that can emit blue, green and red colors. The blue emission originating from CdS core combines to green/orange components originating from ZnS shell and creates an efficiency white light emission. To model this device, at first, we solve Schrödinger and Poisson equations self consistently and obtain eigen energies and wave functions. Then, we calculate the optical gain and internal quantum efficiency (IQE) of a CdS/ZnS LED sample. We investigate the structural parameter effects on the optical properties of the WLED. The numerical results show that the gain profile and IQE curves depend strongly on the structural parameters such as dot size, carrier density and volume scaling parameter. The gain profile becomes higher and wider with increasing the core radius while it becomes less and narrower with increasing the shell thickness. Furthermore, it is found that the volume scaling parameter can manage the system quantum efficiency.
Re-Conceptualising Rural Resources as Countryside Capital: The Case of Rural Tourism
ERIC Educational Resources Information Center
Garrod, Brian; Wornell, Roz; Youell, Ray
2006-01-01
Commentators tend to agree that the rural resource is becoming increasingly subject to pressures arising from an ever wider range of economic, social, political and environmental influences. This paper focuses on the case of rural tourism in illustrating the advantages of adopting a sustainable development approach to identifying suitable policies…
New Perspectives on Human Problem Solving
ERIC Educational Resources Information Center
Goldstone, Robert L.; Pizlo, Zygmunt
2009-01-01
In November 2008 at Purdue University, the 2nd Workshop on Human Problem Solving was held. This workshop, which was a natural continuation of the first workshop devoted almost exclusively to optimization problems, addressed a wider range of topics that reflect the scope of the "Journal of Problem Solving." The workshop was attended by 35…
The Neoliberalization of Higher Education in England: An Alternative is Possible*
ERIC Educational Resources Information Center
Maisuria, Alpesh; Cole, Mike
2017-01-01
In this article, we provide a critical explanation and critique of neoliberalism. We attempt an innovative focus ranging from the wider contemporary political and ideological shifts, to the way in which neoliberal policy specifically influences higher education and the consequences thereof. We follow a narrative logic in three parts where we first…
Sequence Matters but How Exactly? A Method for Evaluating Activity Sequences from Data
ERIC Educational Resources Information Center
Doroudi, Shayan; Holstein, Kenneth; Aleven, Vincent; Brunskill, Emma
2016-01-01
How should a wide variety of educational activities be sequenced to maximize student learning? Although some experimental studies have addressed this question, educational data mining methods may be able to evaluate a wider range of possibilities and better handle many simultaneous sequencing constraints. We introduce Sequencing Constraint…
ERIC Educational Resources Information Center
Adler, Jonathan M.; Matthews, Elizabeth A.
2009-01-01
Students bring an intact, if unarticulated, epistemological perspective into the classroom that influences how they receive and process new information. In this study, students who explored a wider range of perspectives had significantly improved learning outcomes as measured in 3 domains: retention of specific content, retention of general…
Additional Support Needs Reforms and Social Justice in Scotland
ERIC Educational Resources Information Center
Riddell, Sheila; Stead, Joan; Weedon, Elisabet; Wright, Kevin
2010-01-01
New additional support-needs legislation in Scotland sought to recognise the way in which poverty, as well as individual impairment, contribute to the creation of children's difficulties in learning. As well as identifying a wider range of needs, the legislation sought to provide parents, irrespective of social background, with more powerful means…
Learning through a Foreign Language: Models, Methods and Outcomes.
ERIC Educational Resources Information Center
Masih, John, Ed.
This book presents European perspectives on the means of structuring curricula that integrate content and language teaching, drawing on the experience of practitioners at a range of levels. It also provides details of the outcomes of such programs and describes the current and future challenges for wider scale adoption of content and language…
Knowledge Infrastructures and the Inscrutability of Openness in Education
ERIC Educational Resources Information Center
Edwards, Richard
2015-01-01
Openness has a long genealogy in education. Whether through the use of post, radio, television and digital technologies, extending learning opportunities to more and a wider range of people has been a significant aspect of educational history. Transcending barriers to learning has been promoted as the means of opening educational opportunities in…
Activities in Science Related to Space.
ERIC Educational Resources Information Center
National Aeronautics and Space Administration, Washington, DC. Educational Programs Div.
Contained are a collection of science activities based upon forty-six scientific concepts related to space science. These activities are designed for junior high school science, but a much wider grade level range of use is possible. The booklet is primarily intended for teacher use. Each series of concept-oriented activities is independent of the…
Characterizing Twitter Communication--A Case Study of International Engineering Academic Units
ERIC Educational Resources Information Center
Palmer, Stuart
2014-01-01
Engineering academic units might engage with social media for a range of purposes including for general communication with students, staff, alumni, other important stakeholders and the wider community at large; for student recruitment and for marketing and promotion more generally. This paper presents an investigation into the use of Twitter by…
Liquid Spray Characterization in Flow Fields with Centripetal Acceleration
2014-03-27
25 2.4.1 Atomization of Liquid Jets ...volumetric heat release rates, easier light-up, wider burning range, and lower exhaust pollutant emissions [11]. 26 2.4.1 Atomization of Liquid Jets ...Atomization involves the interaction of consolidating and disruptive forces acting on a jet of liquid . The process of atomization can be further
The Politics of Testing When Measures "Go Public"
ERIC Educational Resources Information Center
Henig, Jeffrey R.
2013-01-01
Background/Context: Validity issues are often discussed in technical terms, but the context changes when measures enter broad public debate, and a wider range of interests come into play. Purpose: This article, part of a special section of TCR, considers the political dimensions of validity questions as raised by a keynote address and panel…
ERIC Educational Resources Information Center
Reeves, Matthew Jonathan; Bailey, Richard P.
2016-01-01
Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental psychiatric disorder among children. Despite the noted positive aspects of the disorder, it is often associated with a range of negative outcomes for that are detrimental to children's education and wider well-being. This comprehensive scoping review examined…
The Revised DCDQ: Is It a Suitable Screening Measure for Motor Difficulties in Adolescents?
ERIC Educational Resources Information Center
Pannekoek, Linda; Rigoli, Daniela; Piek, Jan P.; Barrett, Nicholas C.; Schoemaker, Marina
2012-01-01
The parent-rated Developmental Coordination Disorder Questionnaire (DCDQ) has been revised to incorporate a wider age range, including adolescence. In this exploratory study, internal consistency and validity of the DCDQ-2007 was assessed using a community-based sample of 87 adolescents. Psychometric properties of the DCDQ-2007 were investigated…
Interactional Competence in a Paired Speaking Test: Features Salient to Raters
ERIC Educational Resources Information Center
May, Lyn
2011-01-01
Paired speaking tests are now commonly used in both high-stakes testing and classroom assessment contexts. The co-construction of discourse by candidates is regarded as a strength of paired speaking tests, as candidates have the opportunity to display a wider range of interactional competencies, including turn taking, initiating topics, and…
Education Policy Studies in South Africa, 1995-2006
ERIC Educational Resources Information Center
Deacon, Roger; Osman, Ruksana; Buchler, Michelle
2010-01-01
This article reports on findings pertaining to scholarship in education policy drawn from a wider study on all education research in South Africa from 1995 to 2006. This study, which defined education research as broadly pertaining to teaching and/or learning, obtained extensive data from a wide range of sources, including universities, public…
A table for converting pH to hydrogen ion concentration [H+] over the range 5-9.
DOT National Transportation Integrated Search
1968-10-01
The wider use, in the future, of hydrogen ion concentration (H+) rather than pH to describe and evaluate acid-base status will require interconversion of the two notations until a final standard is adopted. The relationship between pH and (H+) is giv...
Burns, Jacky; Conway, David I; Gnich, Wendy; Macpherson, Lorna M D
2017-03-08
Poor health and health inequalities persist despite increasing investment in health improvement programmes across high-income countries. Evidence suggests that to reduce health inequalities, a range of activities targeted at different levels within society and throughout the life course should be employed. There is a particular focus on addressing inequalities in early years as this may influence the experience of health in adulthood. To address the wider determinants of health at a community level, a key intervention which can be considered is supporting patients to access wider community resources. This can include processes such as signposting, referral and facilitation. There is a lack of evidence synthesis in relation to the most effective methods for linking individuals from health services to other services within communities, especially when considering interventions aimed at families with young children. The aim of this study is to understand the way health services can best help parents, carers and families with pre-school children to engage with local services, groups and agencies to address their wider health and social needs. The review may inform future guidance to support families to address wider determinants of health. The study is a systematic review, and papers will be identified from the following electronic databases: Web of Science, Embase, MEDLINE and CINAHL. A grey literature search will be conducted using an internet search engine and specific grey literature databases (TRiP, EThOS and Open Grey). Reference lists/bibliographies of selected papers will be searched. Quality will be assessed using the Effective Public Health Practice Project Quality Assessment Tool for quantitative studies and the CASP tool for qualitative studies. Data will be synthesised in a narrative form and weighted by study quality. It is important to understand how health services can facilitate access to wider services for their patients to address the wider determinants of health. This may impact on the experience of health inequalities. This review focuses on how this can be achieved for families with pre-school children, and the evidence obtained will be useful for informing future guidance on this topic. PROSPERO CRD42016034066.
A new catalogue of ultraluminous X-ray sources (and more!)
NASA Astrophysics Data System (ADS)
Roberts, T.; Earnshaw, H.; Walton, D.; Middleton, M.; Mateos, S.
2017-10-01
Many of the critical issues of ultraluminous X-ray source (ULX) science - for example the prevalence of IMBH and/or ULX pulsar candidates within the wider ULX population - can only be addressed by studying statistical samples of ULXs. Similarly, characterising the range of properties displayed by ULXs, and so understanding their accretion physics, requires large samples of objects. To this end, we introduce a new catalogue of 376 ultraluminous X-ray sources and 1092 less luminous point X-ray sources associated with nearby galaxies, derived from the 3XMM-DR4 catalogue. We highlight applications of this catalogue, for example the identification of new IMBH candidates from the most luminous ULXs; and examining the physics of objects at the Eddington threshold, where their luminosities of ˜ 10^{39} erg s^{-1} indicate their accretion rates are ˜ Eddington. We also show how the catalogue can be used to start to examine a wider range of lower luminosity (sub-ULX) point sources in star forming galaxies than previously accessible through spectral stacking, and argue why this is important for galaxy formation in the high redshift Universe.
Precise and versatile formula for birefringent filters
NASA Astrophysics Data System (ADS)
Shao, Zhongxing
1996-07-01
In an investigation of extraordinary-(E-) ray behavior and the index of refraction for E waves in a uniaxial crystal, a precise and versatile formula for birefringent filters, based on the exact construction of the optical path difference, is set up with neither the approximation Delta n = no - ne less than or equals no (or n e), nor the ambiguity sin( theta )/sin(rw) = ne. The exact construction gives the correct variation of the position and the dimension in each path, yielding the path difference while the filter is tuning. The formula is applicable not only to a filter with its optical axis parallel to the entrance surface (FAPS) but also to a filter with its axis inclined to the surface (FAIS). Also, the formula indicates that a FAIS allows laser wavelengths to be tuned over a wider range than does a FAPS. The origin of the wider range is interpreted to be the greater variation in the index for the FAIS while the filter is tuning. With the help of the formula we design a FAIS for tuning a cw 42.25.Lc.
Acoustic changes in voice after tonsillectomy.
Saida, H; Hirose, H
1996-01-01
The vocal tract from the glottis to the lips is considered to he a resonator and the voice is changeable depending upon the shape of the vocal tract. In this report, we examined the change in pharyngeal size and acoustic feature of voice after tonsillectomy. Subjects were 20 patients. The distance between both anterior pillars (glossopalatine arches), and between both posterior pillars (pharyngopalatine arches) was measured weekly. For acoustic measurements, the five Japanese vowels and Japanese conversational sentences were recorded and analyzed. The distance between both anterior pillars became wider 2 weeks postoperatively, and tended to become narrower thereafter. The distance between both posterior pillars became wider even after 4 weeks postoperatively. No consistent changes in F0, F1 and F2 were found after surgery. Although there was a tendency for a decrease in F3, tonsillectomy did not appear to change the acoustical features of the Japanese vowels remarkably. It was assumed that the subject may adjust the shape of the vocal tract to produce consistent speech sounds after the surgery using auditory feedback.
A simple rule of thumb for elegant prehension.
Mon-Williams, M; Tresilian, J R
2001-07-10
Reaching out to grasp an object (prehension) is a deceptively elegant and skilled behavior. The movement prior to object contact can be described as having two components, the movement of the hand to an appropriate location for gripping the object, the "transport" component, and the opening and closing of the aperture between the fingers as they prepare to grip the target, the "grasp" component. The grasp component is sensitive to the size of the object, so that a larger grasp aperture is formed for wider objects; the maximum grasp aperture (MGA) is a little wider than the width of the target object and occurs later in the movement for larger objects. We present a simple model that can account for the temporal relationship between the transport and grasp components. We report the results of an experiment providing empirical support for our "rule of thumb." The model provides a simple, but plausible, account of a neural control strategy that has been the center of debate over the last two decades.
Tunable and mode-locked laser action of Cr4+ in codoped forsterite Cr, Sc:Mg2SiO4
NASA Astrophysics Data System (ADS)
Sanina, V. V.; Mitrokhin, V. P.; Subbotin, K. A.; Lis, D. A.; Lis, O. N.; Ivanov, A. A.; Zharikov, E. V.
2018-01-01
The laser oscillation of tetravalent chromium and scandium codoped forsterite Cr4+,Sc:Mg2SiO4 single crystal has been demonstrated for the first time for continuous wave, tunable and mode-locked regimes. For comparison, the laser experiments have also been performed in the same configuration with the reference forsterite single crystal solely doped by chromium. The aim of scandium codoping is to inhibit the formation of parasitic trivalent chromium in the crystal. The crystal with scandium demonstrates a wider tuning range, lower lasing threshold and wider mode-locked lasing spectrum than those of the reference crystal, although the total lasing efficiency achieved by both crystals is nearly the same. The obtained results are discussed.
Bioinspired nanovalves with selective permeability and pH sensitivity
NASA Astrophysics Data System (ADS)
Zheng, Z.; Huang, X.; Schenderlein, M.; Moehwald, H.; Xu, G.-K.; Shchukin, D. G.
2015-01-01
Biological systems with controlled permeability and release functionality, which are among the successful examples of living beings to survive in evolution, have attracted intensive investigation and have been mimicked due to their broad spectrum of applications. We present in this work, for the first time, an example of nuclear pore complexes (NPCs)-inspired controlled release system that exhibits on-demand release of angstrom-sized molecules. We do so in a cost-effective way by stabilizing porous cobalt basic carbonates as nanovalves and realizing pH-sensitive release of entrapped subnano cargo. The proof-of-concept work also consists of the establishment of two mathematical models to explain the selective permeability of the nanovalves. Finally, gram-sized (or larger) quantities of the bio-inspired controlled release system can be synthesized through a scaling-up strategy, which opens up opportunities for controlled release of functional molecules in wider practical applications.Biological systems with controlled permeability and release functionality, which are among the successful examples of living beings to survive in evolution, have attracted intensive investigation and have been mimicked due to their broad spectrum of applications. We present in this work, for the first time, an example of nuclear pore complexes (NPCs)-inspired controlled release system that exhibits on-demand release of angstrom-sized molecules. We do so in a cost-effective way by stabilizing porous cobalt basic carbonates as nanovalves and realizing pH-sensitive release of entrapped subnano cargo. The proof-of-concept work also consists of the establishment of two mathematical models to explain the selective permeability of the nanovalves. Finally, gram-sized (or larger) quantities of the bio-inspired controlled release system can be synthesized through a scaling-up strategy, which opens up opportunities for controlled release of functional molecules in wider practical applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06378c
[A difficult stabilisation. Chlorpromazine in the fifties in Belgium].
Majerus, Benoît
2010-01-01
Through a Belgian case study the article tries to trace the gradual stabilisation of chlorpromazine as an antipsychotic in the 1950s. By varying ranges and angles of approach it shows the heterogeneity of actors involved and the semantic bricolage that accompany the marketing of the first antipsychotic. Far from being a revolution, the presence of Largactil in psychiatric practice is rather characterised by integration into a wider range of medicines and sinuous searching to give sense to this new drug.
C4 Photosynthesis in Tree Form Euphorbia Species from Hawaiian Rainforest Sites 1
Pearcy, Robert W.; Troughton, John
1975-01-01
The 13C 12C isotope ratios and the leaf anatomy of 18 species and varieties of Euphorbia native to the Hawaian Islands indicated that all possess C4 photosynthesis. These species range from small prostrate coastal strand shrubs to shrubs and trees in rainforest and bog habitats. The results show that C4 photosynthesis occurs in plants from a much wider range of habitats and life-forms than has been previously reported. PMID:16659208
Shirey, Robert J; Wu, Hsinshun Terry
2018-01-01
This study quantifies the dosimetric accuracy of a commercial treatment planning system as functions of treatment depth, air gap, and range shifter thickness for superficial pencil beam scanning proton therapy treatments. The RayStation 6 pencil beam and Monte Carlo dose engines were each used to calculate the dose distributions for a single treatment plan with varying range shifter air gaps. Central axis dose values extracted from each of the calculated plans were compared to dose values measured with a calibrated PTW Markus chamber at various depths in RW3 solid water. Dose was measured at 12 depths, ranging from the surface to 5 cm, for each of the 18 different air gaps, which ranged from 0.5 to 28 cm. TPS dosimetric accuracy, defined as the ratio of calculated dose relative to the measured dose, was plotted as functions of depth and air gap for the pencil beam and Monte Carlo dose algorithms. The accuracy of the TPS pencil beam dose algorithm was found to be clinically unacceptable at depths shallower than 3 cm with air gaps wider than 10 cm, and increased range shifter thickness only added to the dosimetric inaccuracy of the pencil beam algorithm. Each configuration calculated with Monte Carlo was determined to be clinically acceptable. Further comparisons of the Monte Carlo dose algorithm to the measured spread-out Bragg Peaks of multiple fields used during machine commissioning verified the dosimetric accuracy of Monte Carlo in a variety of beam energies and field sizes. Discrepancies between measured and TPS calculated dose values can mainly be attributed to the ability (or lack thereof) of the TPS pencil beam dose algorithm to properly model secondary proton scatter generated in the range shifter. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.
HIGH RATES OF EVOLUTION PRECEDED THE ORIGIN OF BIRDS
Puttick, Mark N; Thomas, Gavin H; Benton, Michael J; Polly, P David
2014-01-01
The origin of birds (Aves) is one of the great evolutionary transitions. Fossils show that many unique morphological features of modern birds, such as feathers, reduction in body size, and the semilunate carpal, long preceded the origin of clade Aves, but some may be unique to Aves, such as relative elongation of the forelimb. We study the evolution of body size and forelimb length across the phylogeny of coelurosaurian theropods and Mesozoic Aves. Using recently developed phylogenetic comparative methods, we find an increase in rates of body size and body size dependent forelimb evolution leading to small body size relative to forelimb length in Paraves, the wider clade comprising Aves and Deinonychosauria. The high evolutionary rates arose primarily from a reduction in body size, as there were no increased rates of forelimb evolution. In line with a recent study, we find evidence that Aves appear to have a unique relationship between body size and forelimb dimensions. Traits associated with Aves evolved before their origin, at high rates, and support the notion that numerous lineages of paravians were experimenting with different modes of flight through the Late Jurassic and Early Cretaceous. PMID:24471891
An Optimized Control for LLC Resonant Converter with Wide Load Range
NASA Astrophysics Data System (ADS)
Xi, Xia; Qian, Qinsong
2017-05-01
This paper presents an optimized control which makes LLC resonant converters operate with a wider load range and provides good closed-loop performance. The proposed control employs two paralleled digital compensations to guarantee the good closed-loop performance in a wide load range during the steady state, an optimized trajectory control will take over to change the gate-driving signals immediately at the load transients. Finally, the proposed control has been implemented and tested on a 150W 200kHz 400V/24V LLC resonant converter and the result validates the proposed method.
Dudits, Dénes; Török, Katalin; Cseri, András; Paul, Kenny; Nagy, Anna V; Nagy, Bettina; Sass, László; Ferenc, Györgyi; Vankova, Radomira; Dobrev, Petre; Vass, Imre; Ayaydin, Ferhan
2016-03-01
The biomass productivity of the energy willow Salix viminalis as a short-rotation woody crop depends on organ structure and functions that are under the control of genome size. Colchicine treatment of axillary buds resulted in a set of autotetraploid S. viminalis var. Energo genotypes (polyploid Energo [PP-E]; 2n = 4x = 76) with variation in the green pixel-based shoot surface area. In cases where increased shoot biomass was observed, it was primarily derived from larger leaf size and wider stem diameter. Autotetraploidy slowed primary growth and increased shoot diameter (a parameter of secondary growth). The duplicated genome size enlarged bark and wood layers in twigs sampled in the field. The PP-E plants developed wider leaves with thicker midrib and enlarged palisade parenchyma cells. Autotetraploid leaves contained significantly increased amounts of active gibberellins, cytokinins, salicylic acid, and jasmonate compared with diploid individuals. Greater net photosynthetic CO2 uptake was detected in leaves of PP-E plants with increased chlorophyll and carotenoid contents. Improved photosynthetic functions in tetraploids were also shown by more efficient electron transport rates of photosystems I and II. Autotetraploidization increased the biomass of the root system of PP-E plants relative to diploids. Sections of tetraploid roots showed thickening with enlarged cortex cells. Elevated amounts of indole acetic acid, active cytokinins, active gibberellin, and salicylic acid were detected in the root tips of these plants. The presented variation in traits of tetraploid willow genotypes provides a basis to use autopolyploidization as a chromosome engineering technique to alter the organ development of energy plants in order to improve biomass productivity. © 2016 American Society of Plant Biologists. All Rights Reserved.
Dudits, Dénes; Török, Katalin; Cseri, András; Paul, Kenny; Nagy, Bettina; Sass, László; Ferenc, Györgyi; Vankova, Radomira; Dobrev, Petre; Vass, Imre; Ayaydin, Ferhan
2016-01-01
The biomass productivity of the energy willow Salix viminalis as a short-rotation woody crop depends on organ structure and functions that are under the control of genome size. Colchicine treatment of axillary buds resulted in a set of autotetraploid S. viminalis var. Energo genotypes (polyploid Energo [PP-E]; 2n = 4x = 76) with variation in the green pixel-based shoot surface area. In cases where increased shoot biomass was observed, it was primarily derived from larger leaf size and wider stem diameter. Autotetraploidy slowed primary growth and increased shoot diameter (a parameter of secondary growth). The duplicated genome size enlarged bark and wood layers in twigs sampled in the field. The PP-E plants developed wider leaves with thicker midrib and enlarged palisade parenchyma cells. Autotetraploid leaves contained significantly increased amounts of active gibberellins, cytokinins, salicylic acid, and jasmonate compared with diploid individuals. Greater net photosynthetic CO2 uptake was detected in leaves of PP-E plants with increased chlorophyll and carotenoid contents. Improved photosynthetic functions in tetraploids were also shown by more efficient electron transport rates of photosystems I and II. Autotetraploidization increased the biomass of the root system of PP-E plants relative to diploids. Sections of tetraploid roots showed thickening with enlarged cortex cells. Elevated amounts of indole acetic acid, active cytokinins, active gibberellin, and salicylic acid were detected in the root tips of these plants. The presented variation in traits of tetraploid willow genotypes provides a basis to use autopolyploidization as a chromosome engineering technique to alter the organ development of energy plants in order to improve biomass productivity. PMID:26729798
Model based analysis of piezoelectric transformers.
Hemsel, T; Priya, S
2006-12-22
Piezoelectric transformers are increasingly getting popular in the electrical devices owing to several advantages such as small size, high efficiency, no electromagnetic noise and non-flammable. In addition to the conventional applications such as ballast for back light inverter in notebook computers, camera flash, and fuel ignition several new applications have emerged such as AC/DC converter, battery charger and automobile lighting. These new applications demand high power density and wide range of voltage gain. Currently, the transformer power density is limited to 40 W/cm(3) obtained at low voltage gain. The purpose of this study was to investigate a transformer design that has the potential of providing higher power density and wider range of voltage gain. The new transformer design utilizes radial mode both at the input and output port and has the unidirectional polarization in the ceramics. This design was found to provide 30 W power with an efficiency of 98% and 30 degrees C temperature rise from the room temperature. An electro-mechanical equivalent circuit model was developed to describe the characteristics of the piezoelectric transformer. The model was found to successfully predict the characteristics of the transformer. Excellent matching was found between the computed and experimental results. The results of this study will allow to deterministically design unipoled piezoelectric transformers with specified performance. It is expected that in near future the unipoled transformer will gain significant importance in various electrical components.
SU-F-T-533: Study of Dosimetric Properties of Cadmium Free Alloy Used in Compensator Based IMRT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyagi, A; Kaushik, S; Guru Jambheshwar University of Science & Technology, Hisar, Haryana
Purpose: To study the dosimetric properties of cadmium free alloy which is used in compensator based IMRT. Methods: A mixture of 30% of lead,52% of bismuth and 18% of tin was used to prepare alloy. We prepared slabs of different thicknesses ranging from 0.71 cm to 6.14 cm. Density of alloy was measured by Archimedes’ principle using SI-234 Denver instrument and water as buoyant liquid. Transmission, linear attenuation coefficient (µ), tissue phantom ration (TPR), beam hardening, surface dose (Ds), percentage depth dose (PDD) and effect of scatter were measured and analyze for different field size and different thickness of compensatormore » for 6 MV photon beam. Measurements were carried out at 100 cm SSD and 160 cm SSD. Results: Density of alloy was found to be 9.5456 gm/cm3. Melting point of alloy is 90–95 °C. For a field size of 10×10 cm2 µ was 0.4253 cm-1 at 100 cm SSD. Calculated TPR was found to be within 3 % of measured TPR. Ds was found to be decreasing with increasing thickness of compensator. 1cm, 1.98 cm and 4.16 cm thick compensator slab decreased surface dose by 4.2%, 6.1% and 9.5% respectively for a field size of 10×10cm2 at 100 cm SSD. As field size increases Ds increases for a given compensator thickness. This is due to increase in amount of scattered dose from wider collimator opening. For smaller field size, PDDs are increased from 3.0% to 5.5% of open beam PDDs as compensator thickness increases from 1 cm to 6.14 cm at a depth of 10 cm in water. For larger field size variation in PDDs is not significant. Conclusion: High degree of modulation can be achieved from this compensator material, which is essential in compensator based IMRT. Dosimetric properties analyzed in this study establish this alloy as a reliable, cost effective, reusable compensator material.« less
A Model based Examination of Conditions for Ignition of Turbidity Currents on Slopes
NASA Astrophysics Data System (ADS)
Mehta, A. J.; Krishna, G.
2009-12-01
Turbidity currents form a major mechanism for the movement of sediment in the natural environment. Self-accelerating turbidity currents over continental slopes are of considerable scientific and engineering interest due to their role as agents for submarine sediment transportation from the shelf to the seabed. Such currents are called ignitive provided they eventually reach a catastrophic state as acceleration results in high sediment loads due to erosion of the sloping bed. A numerical model, which treats the fluid and the particles as two separate phases, is applied to investigate the effects of particle size, initial flow friction velocity and mild bed slope on the ignitive condition. Laboratory experimental data have been included as part of the analysis for qualitative comparison purposes. Ignition for the smallest of the three selected sizes (0.21mm) of medium sand typical of Florida beaches was found to depend on the initial conditions at the head of the slope as determined by the pressure gradient. Bed slope seemed to be of secondary importance. For the two sands with larger grain sizes (0.28mm and 0.35mm) the slope was found to play a more important role when compared to the initial pressure gradient. For a given pressure gradient, increasing the slope increased the likelihood of self-acceleration. It is concluded that in general ignition cannot be defined merely in terms of positive values of the velocity gradient and the sediment flux gradient along the slope. Depending on particle size the initial pressure gradient can also play a role. For the selected initial conditions (grain size, pressure gradient and bed slope), out of the 54 combinations tested, all except three satisfied the Knapp-Bagnold criterion for auto-suspension irrespective of whether the turbid current was ignitive or non-ignitive. In all 54 cases the current was found to erode the bed. Further use of the model will require accommodation of wider ranges of sediment size and bed density, and a thorough verification against experimental data.
Pore size engineering applied to the design of separators for nickel-hydrogen cells and batteries
NASA Technical Reports Server (NTRS)
Abbey, K. M.; Britton, D. L.
1983-01-01
Pore size engineering in starved alkaline multiplate cells involves adopting techniques to widen the volume tolerance of individual cells. Separators with appropriate pore size distributions and wettability characteristics (capillary pressure considerations) to have wider volume tolerances and an ability to resist dimensional changes in the electrodes were designed. The separators studied for potential use in nickel-hydrogen cells consist of polymeric membranes as well as inorganic microporous mats. In addition to standard measurements, the resistance and distribution of electrolyte as a function of total cell electrolyte content were determined. New composite separators consisting of fibers, particles and/or binders deposited on Zircar cloth were developed in order to engineer the proper capillary pressure characteristics in the separator. These asymmetric separators were prepared from a variety of fibers, particles and binders. Previously announced in STAR as N83-24571
When size matters: attention affects performance by contrast or response gain.
Herrmann, Katrin; Montaser-Kouhsari, Leila; Carrasco, Marisa; Heeger, David J
2010-12-01
Covert attention, the selective processing of visual information in the absence of eye movements, improves behavioral performance. We found that attention, both exogenous (involuntary) and endogenous (voluntary), can affect performance by contrast or response gain changes, depending on the stimulus size and the relative size of the attention field. These two variables were manipulated in a cueing task while stimulus contrast was varied. We observed a change in behavioral performance consonant with a change in contrast gain for small stimuli paired with spatial uncertainty and a change in response gain for large stimuli presented at one location (no uncertainty) and surrounded by irrelevant flanking distracters. A complementary neuroimaging experiment revealed that observers' attention fields were wider with than without spatial uncertainty. Our results support important predictions of the normalization model of attention and reconcile previous, seemingly contradictory findings on the effects of visual attention.
A method for the formation of Pt metal nanoparticle arrays using nanosecond pulsed laser dewetting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Owusu-Ansah, Ebenezer; Horwood, Corie A.; Birss, Viola I.
2015-05-18
Nanosecond pulsed laser dewetting of Pt thin films, deposited on a dimpled Ta (DT) surface, has been studied here in order to form ordered Pt nanoparticle (NP) arrays. The DT substrate was fabricated via a simple electrochemical anodization process in a highly concentrated H{sub 2}SO{sub 4} and HF solution. Pt thin films (3–5 nm) were sputter coated on DT and then dewetted under vacuum to generate NPs using a 355 nm laser radiation (6–9 ns, 10 Hz). The threshold laser fluence to fully dewet a 3.5 nm thick Pt film was determined to be 300 mJ/cm{sup 2}. Our experiments have shown that shorter irradiation timesmore » (≤60 s) produce smaller nanoparticles with more uniform sizes, while longer times (>60 s) give large nanoparticles with wider size distributions. The optimum laser irradiation time of 1 s (10 pulses) has led to the formation of highly ordered Pt nanoparticle arrays with an average nanoparticle size of 26 ± 3 nm with no substrate deformation. At the optimum condition of 1 s and 500 mJ/cm{sup 2}, as many as 85% of the dewetted NPs were found neatly in the well-defined dimples. This work has demonstrated that pulsed laser dewetting of Pt thin films on a pre-patterned dimpled substrate is an efficient and powerful technique to produce highly ordered Pt nanoparticle arrays. This method can thus be used to produce arrays of other high-melting-point metal nanoparticles for a range of applications, including electrocatalysis, functionalized nanomaterials, and analytical purposes.« less
Effect of AlCl3 concentration on nanoparticle removal by coagulation.
Zhang, Lizhu; Mao, Jingchun; Zhao, Qing; He, Shaobo; Ma, Jun
2015-12-01
In recent years, engineered nanoparticles, as a new group of contaminants emerging in natural water, have been given more attention. In order to understand the behavior of nanoparticles in the conventional water treatment process, three kinds of nanoparticle suspensions, namely multi-walled carbon nanotube-humic acid (MWCNT-HA), multi-walled carbon nanotube-N,N-dimethylformamide (MWCNT-DMF) and nanoTiO2-humic acid (TiO2-HA) were employed to investigate their coagulation removal efficiencies with varying aluminum chloride (AlCl3) concentrations. Results showed that nanoparticle removal rate curves had a reverse "U" shape with increasing concentration of aluminum ion (Al(3+)). More than 90% of nanoparticles could be effectively removed by an appropriate Al(3+) concentration. At higher Al(3+) concentration, nanoparticles would be restabilized. The hydrodynamic particle size of nanoparticles was found to be the crucial factor influencing the effective concentration range (ECR) of Al(3+) for nanoparticle removal. The ECR of Al(3+) followed the order MWCNT-DMF>MWCNT-HA>TiO2-HA, which is the reverse of the nanoparticle size trend. At a given concentration, smaller nanoparticles carry more surface charges, and thus consume more coagulants for neutralization. Therefore, over-saturation occurred at relatively higher Al(3+) concentration and a wider ECR was obtained. The ECR became broader with increasing pH because of the smaller hydrodynamic particle size of nanoparticles at higher pH values. A high ionic strength of NaCl can also widen the ECR due to its strong potential to compress the electric double layer. It was concluded that it is important to adjust the dose of Al(3+) in the ECR for nanoparticle removal in water treatment. Copyright © 2015. Published by Elsevier B.V.
Carbon ions irradiation on nano- and microcrystalline CaSO4 : Dy
NASA Astrophysics Data System (ADS)
Salah, Numan
2008-08-01
Nanoparticles of CaSO4 : Dy phosphor with a particle size of around 30 nm have been prepared by the chemical co-precipitation technique. Pellet samples of the nanomaterials were irradiated by a 75 MeV C6+ ion beam at the fluence range 1 × 109-1 × 1013 ions cm-2. Thermoluminescence (TL) glow curves of the irradiated samples were recorded and studied. The microcrystalline form of this sample is also included in the study with the aim of reporting a comparative measurement. The TL analysis shows that the glow curve of the nanomaterial has two peaks at around 166 and 210 °C. These peaks are similar to those induced in the microcrystalline sample with a slight difference in their TL response. The second peak is more prominent in the case of the microcrystalline sample at low fluences, while the first one dominates in the nanostructured sample mainly at higher fluences. The TRIM code based on Monte Carlo simulation was also used for calculating some ion beam parameters. Dosimetric properties of the carbon ion beam irradiated materials show that the nanostructure material has excellent features such as a simple glow curve structure and a linear TL response over a wider range than the corresponding microcrystalline sample. These results show that the nanostructure form of CaSO4 : Dy might be useful for detecting the high doses of carbon ions used in radiotherapy. Thermal analysis of the prepared nano- and microcrystalline materials was also done in the range 50-500 °C using thermogravimetry analysis and differential thermal analysis. No phase transitions within this range of heating for both the materials are observed.
Costanzo, Alessandro; Sandri, Andrea; Regis, Dario; Trivellin, Giacomo; Pierantoni, Silvia; Samaila, Elena; Magnan, Bruno
2017-10-18
Radiofrequency ablation (RFA) is the gold standard for the treatment of symptomatic osteoid osteoma (OO) as RFA yields both a high success and low complication rate. It has been widely utilized over the years, but recurrences of OO after this treatment have been documented. These recurrences may be the result of various factors, including incomplete tumor ablation, and are significantly higher in lesions greater than 10 mm. Thus, the need to induce thermal ablation in a wider area led us to use a Multi-Tined Expandable Electrode System (MTEES). In this study we examined the efficacy and safety of RFA using a MTEES in symptomatic OO. Between January 2005 and June 2007, 16 patients with symptomatic OO were treated by CT-guided percutaneous RFA using a MTEES. The diameter of OO ranged from 6 to 15 mm (mean 10±2.6 mm). Patients were evaluated for clinical outcomes, complications and recurrence. Pain evaluation was assessed preoperatively, 2 weeks postoperatively and at last follow-up. Clinical follow-up was available for all patients at a mean of 84.3 months (range 73-96 months). Mean preoperative VAS score was 7.4 (range 5-9), two weeks after the procedure mean VAS score was 0.3 (range 0-1) with a mean change of -7.06 points (p<0.0001). At the last follow-up a complete relief from pain has been observed in all patients. No major and minor complications were observed nor recurrences. RFA using a MTEES has been effective, safe and reliable for the treatment of OOs. This system, by increasing the size of the necrosis, could be a viable alternative to the single needle electrode in lesions larger than 10 mm, reducing the risk of recurrence.
Kuhlmann, A; Schmidt, T; Treskova, M; López-Bastida, J; Linertová, R; Oliva-Moreno, J; Serrano-Aguilar, P; Posada-de-la-Paz, M; Kanavos, P; Taruscio, D; Schieppati, A; Iskrov, G; Péntek, M; Delgado, C; von der Schulenburg, J M; Persson, U; Chevreul, K; Fattore, G
2016-04-01
The aim of this study was to determine the economic burden from a societal perspective and the health-related quality of life (HRQOL) of patients with juvenile idiopathic arthritis (JIA) in Europe. We conducted a cross-sectional study of patients with JIA from Germany, Italy, Spain, France, the United Kingdom, Bulgaria, and Sweden. Data on demographic characteristics, healthcare resource utilization, informal care, labor productivity losses, and HRQOL were collected from the questionnaires completed by patients or their caregivers. HRQOL was measured with the EuroQol 5-domain (EQ-5D-5L) questionnaire. A total of 162 patients (67 Germany, 34 Sweden, 33 Italy, 23 United Kingdom, 4 France, and 1 Bulgaria) completed the questionnaire. Excluding Bulgarian results, due to small sample size, country-specific annual health care costs ranged from €18,913 to €36,396 (reference year: 2012). Estimated direct healthcare costs ranged from €11,068 to €22,138; direct non-healthcare costs ranged from €7837 to €14,155 and labor productivity losses ranged from €0 to €8715. Costs are also shown to differ between children and adults. The mean EQ-5D index score for JIA patients was estimated at between 0.44 and 0.88, and the mean EQ-5D visual analogue scale score was estimated at between 62 and 79. JIA patients incur considerable societal costs and experience substantial deterioration in HRQOL in some countries. Compared with previous studies, our results show a remarkable increase in annual healthcare costs for JIA patients. Reasons for the increase are the inclusion of non-professional caregiver costs, a wider use of biologics, and longer hospital stays.
Marshall Space Flight Center's Impact Testing Facility Capabilities
NASA Technical Reports Server (NTRS)
Finchum, Andy; Hubbs, Whitney; Evans, Steve
2008-01-01
Marshall Space Flight Center s (MSFC) Impact Testing Facility (ITF) serves as an important installation for space and missile related materials science research. The ITF was established and began its research in spacecraft debris shielding in the early 1960s, then played a major role in the International Space Station debris shield development. As NASA became more interested in launch debris and in-flight impact concerns, the ITF grew to include research in a variety of impact genres. Collaborative partnerships with the DoD led to a wider range of impact capabilities being relocated to MSFC as a result of the closure of Particle Impact Facilities in Santa Barbara, California. The Particle Impact Facility had a 30 year history in providing evaluations of aerospace materials and components during flights through rain, ice, and solid particle environments at subsonic through hypersonic velocities. The facility s unique capabilities were deemed a "National Asset" by the DoD. The ITF now has capabilities including environmental, ballistic, and hypervelocity impact testing utilizing an array of air, powder, and two-stage light gas guns to accommodate a variety of projectile and target types and sizes. Numerous upgrades including new instrumentation, triggering circuitry, high speed photography, and optimized sabot designs have been implemented. Other recent research has included rain drop demise characterization tests to obtain data for inclusion in on-going model development. The current and proposed ITF capabilities range from rain to micrometeoroids allowing the widest test parameter range possible for materials investigations in support of space, atmospheric, and ground environments. These test capabilities including hydrometeor, single/multi-particle, ballistic gas guns, exploding wire gun, and light gas guns combined with Smooth Particle Hydrodynamics Code (SPHC) simulations represent the widest range of impact test capabilities in the country.
Technical standards for micro sensors in surgery and minimally invasive therapy.
Neuder; Dehm
2004-04-01
The development of medical applications is fuelled in the context of steadily growing needs and the requirement of lowering overall costs. Micro systems will have an extremely important impact on medical technology in the future. The great challenges for the wider use of micro structures in health applications are biocompatibility and mass production. Especially small and medium-sized enterprises (SMEs) need help to overcome these problems by free access to knowledge, the availability of standards and contacts to partners.
1980-02-01
weighted according to priorities. Based on the military mission, priorities should be set where the use of advanced technology promises the highest defense...particular sizes, weights , capabilities should be assigned and which particular company should take the lead. It is a rather wider picture than just...directed at competi- tion, as such, but at the loss of time and money and the failure to achieve the requisite level of interoperability in Europe. I
Walker, David; Yu, Guoyu; Li, Hongyu; Messelink, Wilhelmus; Evans, Rob; Beaucamp, Anthony
2012-08-27
Segment-edges for extremely large telescopes are critical for observations requiring high contrast and SNR, e.g. detecting exo-planets. In parallel, industrial requirements for edge-control are emerging in several applications. This paper reports on a new approach, where edges are controlled throughout polishing of the entire surface of a part, which has been pre-machined to its final external dimensions. The method deploys compliant bonnets delivering influence functions of variable diameter, complemented by small pitch tools sized to accommodate aspheric mis-fit. We describe results on witness hexagons in preparation for full size prototype segments for the European Extremely Large Telescope, and comment on wider applications of the technology.
Noise-driven neuromorphic tuned amplifier.
Fanelli, Duccio; Ginelli, Francesco; Livi, Roberto; Zagli, Niccoló; Zankoc, Clement
2017-12-01
We study a simple stochastic model of neuronal excitatory and inhibitory interactions. The model is defined on a directed lattice and internodes couplings are modulated by a nonlinear function that mimics the process of synaptic activation. We prove that such a system behaves as a fully tunable amplifier: the endogenous component of noise, stemming from finite size effects, seeds a coherent (exponential) amplification across the chain generating giant oscillations with tunable frequencies, a process that the brain could exploit to enhance, and eventually encode, different signals. On a wider perspective, the characterized amplification process could provide a reliable pacemaking mechanism for biological systems. The device extracts energy from the finite size bath and operates as an out of equilibrium thermal machine, under stationary conditions.
What Can the Work of Habermas Offer Educational Researcher Development Programmes?
ERIC Educational Resources Information Center
Garland, Paul
2014-01-01
Although certain aspects of the work of Habermas have had much influence on emancipatory and action research, this article draws on a wider range of his thinking in order to explore how his ideas can inform the content and process of educational researcher development programmes. Habermas's theory of communicative action, his discourse ethics…
ERIC Educational Resources Information Center
Rudd, Tim
2017-01-01
This paper offers conceptual and theoretical insights relating to the Teaching Excellence Framework (TEF), highlighting a range of potential systemic and institutional outcomes and issues. The paper is organised around three key areas of discussion that are often under-explored in debates. Firstly, after considering the TEF in the wider context of…
ERIC Educational Resources Information Center
Welch, Karla Conn; Hieb, Jeffrey; Graham, James
2015-01-01
Coursework that instills patterns of rigorous logical thought has long been a hallmark of the engineering curriculum. However, today's engineering students are expected to exhibit a wider range of thinking capabilities both to satisfy ABET requirements and to prepare the students to become successful practitioners. This paper presents the initial…
A Review of Self-Report and Alternative Approaches in the Measurement of Student Motivation
ERIC Educational Resources Information Center
Fulmer, Sara M.; Frijters, Jan C.
2009-01-01
Within psychological and educational research, self-report methodology dominates the study of student motivation. The present review argues that the scope of motivation research can be expanded by incorporating a wider range of methodologies and measurement tools. Several authors have suggested that current study of motivation is overly reliant on…
ERIC Educational Resources Information Center
Ari, Omer
2009-01-01
Fluency instruction has had limited effects on reading comprehension relative to reading rate and prosodic reading (Dowhower, 1987; Herman, 1985; National Institute of Child Health and Human Development, 2000a). More specific components (i.e., error detection) of comprehension may yield larger effects through exposure to a wider range of materials…
ERIC Educational Resources Information Center
Loyalka, Prashant Kumar
2009-01-01
Since the late 1990s, China has dramatically increased its college enrollments, the number and diversity of its higher education institutions, university tuition fees, and financial aid. Now students from a wider range of backgrounds have significantly more opportunities to attend college and also compete for entry into more selective…
Transforming Science Education for the Anthropocene--Is It Possible?
ERIC Educational Resources Information Center
Gilbert, Jane
2016-01-01
Since its inception, science education has been the focus of a great many reform attempts. In general, the aim has been to improve science understanding and/or make science study more interesting and/or relevant to a wider range of students. However, these reform attempts have had limited success. This paper argues that this is in part because…
The Socio-Cultural and Learning Experiences of Music Students in a British University
ERIC Educational Resources Information Center
Dibben, Nicola
2006-01-01
Research into student experience in Higher Education has largely focused on students' role as learners. However, the student experience encompasses a much wider range of behaviours and beliefs than can be captured through a focus on teaching and learning alone. I report the findings of a research project which explored student experience in the…
ERIC Educational Resources Information Center
Stansfield, Jayne
2008-01-01
To make the Mathematics Enhancement Course (MEC) students realize that mathematics exist in a wider range of forms and environments than most will have encountered before, they are sent out on several trips and visits during the six-month course. This year one of the trips was to spend a day at the ATM conference. Afterwards the students had to…
Galactic water vapor emission: further observations of variability.
Knowles, S H; Mayer, C H; Sullivan, W T; Cheung, A C
1969-10-10
Recent observations of the 1.35-centimeter line emission of water vapor from galactic sources show short-term variability in the spectra of several sources. Two additional sources, Cygnus 1 and NGC 6334N, have been observed, and the spectra of W49 and VY Canis Majoris were measured over a wider range of radial velocity.
Measures of Disadvantage: Is Car Ownership a Good Indicator?
ERIC Educational Resources Information Center
Johnson, Victoria; Currie, Graham; Stanley, Janet
2010-01-01
A need to better understand the multidimensional nature of disadvantage is leading to the adoption of a wider range of measurement variables. One variable now commonly adopted is zero car ownership. This paper challenges the logic of including "not having a car" as an indicator of disadvantage. It argues that this can distort the real picture of…
What We Learned from a Tomato: Partnering with a Content Expert Plants New Ideas for Instruction
ERIC Educational Resources Information Center
Ermeling, Bradley A.
2014-01-01
The interactions described in this article represent an example of teachers expanding horizons of instructional plans as a direct result of outside expert contributions. After alerting teachers to oversimplified claims about the benefits of lycopene, the research fellow presented the team with a wider range of instructional options to consider…
The Relations Between Student Organizations and the Wider University. Final Report.
ERIC Educational Resources Information Center
Gamson, Zelda F.
This report presents the findings from a study of student organizations at the University of Michigan. Four religious groups, 5 political groups, 10 sororities and 10 fraternities were chosen to represent a range of groups within each of the types. The study was undertaken to determine (1) the impact of formal student organizations on their…
Parent-Child Moments of Meeting in Art-Making with Collage, iPad, Tuxpaint and Crayons
ERIC Educational Resources Information Center
Sakr, Mona; Kucirkova, Natalia
2017-01-01
Previous research suggests that parent-child art making can foster opportunities for closeness between children and parents. Most studies however, have focused on art-making that involves paint and paper, or non-digital drawing technologies. There is a need for researchers to consider how a wider range of technologies, including digital…
Reflecting on the Challenges of Applied Theatre in Kenya
ERIC Educational Resources Information Center
Okuto, Maxwel; Smith, Bobby
2017-01-01
In this article the authors draw on their own experience and research in applied theatre in Kenya in order to reflect on challenges currently facing practitioners working in the country. In order to outline the range of challenges faced by practitioners, issues related to the wider landscapes of government and politics in Kenya are explored,…
The mouse lymphoma assay is widely used to identify chemicals that are capable of inducing mutational damages. The Tk+/- gene located on an autosome in mouse lymphoma cells may recover a wider range of mutational events than the X-linked Hprt locus. However, chemical-induced muta...
The College Ladder: Linking Secondary and Postsecondary Education for Success for All Students
ERIC Educational Resources Information Center
Lerner, Jennifer Brown; Brand, Betsy
2006-01-01
This compendium identifies and describes schools, programs, and policies that link secondary and postsecondary education to help students earn college credit or take college-level courses while in high school. It raises issues for practitioners and policymakers to consider as these program grow and target a wider range of students. This compendium…
Resource Delivery and Teaching in Live Chat Reference: Comparing Two Libraries
ERIC Educational Resources Information Center
Dempsey, Paula R.
2017-01-01
This study investigates how reference staff at two libraries balance teaching with resource delivery in live chat reference. Analysis of 410 transcripts from one week shows that one library tends to deliver more resources from a wider range of database suggestions, to take more time in chat interactions, and to incorporate more teaching behavior…
Reviews of National Policies for Education: Quality Assurance in Higher Education in Chile 2013
ERIC Educational Resources Information Center
OECD Publishing (NJ3), 2013
2013-01-01
Growth and diversity have characterised higher education in OECD countries for fifty years. Chile is no exception and has experienced dramatic increases in the number of students, the range of institutions and the programmes that they offer. But wider participation and diversification are only part of the story. Chilean society remains highly…
Three Million Apprenticeships: Building Ladders of Opportunity
ERIC Educational Resources Information Center
Learning and Work Institute, 2017
2017-01-01
Apprenticeships are a great way to combine learning and earning and meet employers' skills needs. That is why they have a long history dating back several centuries, though today's apprenticeships have a wider focus including on all ages, a range of levels, and existing as well as new employees. Changes in the economy, and the importance of skills…
Conceptual Design for the New RPI 2020 Linac
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adolphsen, C.; Bane, K.; Dolgashev, V.
2014-10-29
The Rensselaer Polytechnic Institute (RPI) spectrometer is an installation based on an L-band linear accelerator designed and installed many decades ago. While this installation has served many important experiments over the decades, a new more powerful and more flexible linac to serve a wider range of experiments is envisioned as an upgrade to the existing installation by 2020.
Semantic Interaction in Early and Late Bilinguals: All Words Are Not Created Equally
ERIC Educational Resources Information Center
Gathercole, Virginia C. Mueller; Moawad, Ruba Abdelmatloub
2010-01-01
This study examines L1-L2 interaction in semantic categorization in early and late L2 learners. Word categories that overlapped but were not identical in Arabic and English were tested. Words always showed a "wider" range of application in one language, "narrower" in the other. Three types of categories--"classical", "radial", and…
Do Junior High School Students Perceive Their Learning Environment as Constructivist?
ERIC Educational Resources Information Center
Moustafa, Asely; Ben-Zvi-Assaraf, Orit; Eshach, Haim
2013-01-01
The purpose of this study is to examine the manner in which the features of a constructivist learning environment, and the mechanisms at its base, are expressed in junior high school students' conceptions. Our research is based on an integration of quantitative and qualitative approaches, deigned to provide a wider ranging and deeper…
Implications of non-covalent interactions in zein-starch dough and bread quality
USDA-ARS?s Scientific Manuscript database
Breads made from non-wheat flours are made from thick batters and are lower quality than wheat bread. The development of visco-elastic doughs from non-wheat proteins would allow a wider range of gluten-free products and would improve the quality of such foods. Only recently has the mechanism of zei...
Framing health for land-use planning legislation: A qualitative descriptive content analysis.
Harris, Patrick; Kent, Jennifer; Sainsbury, Peter; Thow, Anne Marie
2016-01-01
Framing health as a relevant policy issue for other sectors is not well understood. A recent review of the New South Wales (Australia) land-use planning system resulted in the drafting of legislation with an internationally unprecedented focus on human health. We apply a political science approach to investigate the question 'how and to what extent were health and wider issues framed in submissions to the review?' We investigated a range of stakeholder submissions including health focussed agencies (n = 31), purposively identified key stakeholders with influence on the review (n = 24), and a random sample of other agencies and individuals (n = 47). Using qualitative descriptive analysis we inductively coded for the term 'health' and sub-categories. We deductively coded for 'wider concerns' using a locally endorsed 'Healthy Urban Development Checklist'. Additional inductive analysis uncovered further 'wider concerns'. Health was explicitly identified as a relevant issue for planning policy only in submissions by health-focussed agencies. This framing concerned the new planning system promoting and protecting health as well as connecting health to wider planning concerns including economic issues, transport, public open space and, to a slightly lesser extent, environmental sustainability. Key stakeholder and other agency submissions focussed on these and other wider planning concerns but did not mention health in detail. Health agency submissions did not emphasise infrastructure, density or housing as explicitly as others. Framing health as a relevant policy issue has the potential to influence legislative change governing the business of other sectors. Without submissions from health agencies arguing the importance of having health as an objective in the proposed legislation it is unlikely health considerations would have gained prominence in the draft bill. The findings have implications for health agency engagement with legislative change processes and beyond in land use planning. Copyright © 2015 Elsevier Ltd. All rights reserved.
Dorchin, Netta; Astrin, Jonas J.; Bodner, Levona; Harris, Keith M.
2015-01-01
The Palaearctic gall-midge genus Ozirhincus is unique among the Cecidomyiidae for its morphology and biology. Unlike most other phytophagous gall midges, species in this genus do not induce galls but develop inside achenes of Asteraceae plants. The heads of adults are characterized by an unusually elongate proboscis, the function of which is unclear. Despite a lot of attention from taxonomists in the 19th and early 20th century, a proper revision of the genus has been hindered by complex host associations, the loss of most relevant type material, and the lack of a thorough comparative study of all life stages. The present revision integrated morphological, molecular, and life-history data to clearly define species boundaries within Ozirhincus, and delimit host-plant ranges for each of them. A phylogenetic analysis based on the mitochondrial COI and 16S genes confirmed the validity of four distinct species but did not resolve the relationships among them. All species are oligophages, and some may occur together on the same host plant. Species with wider host-plant ranges have wider European and circum-Mediterranean distribution ranges, whereas species with narrower host ranges are limited to Europe and the Russian Far East. As part of the present work, O. hungaricus is reinstated from synonymy, O. tanaceti is synonymized under O. longicollis, neotypes are designated for O. longicollis and O. millefolii, and a lectotype is designated for O. anthemidis. PMID:26134526
NASA Astrophysics Data System (ADS)
Watkins, N. W.; Chapman, S. C.; Hnat, B.
2011-12-01
The idea that there might not be a typical scale for energy release in some space physics systems is a relatively new one [see e.g. mini-review of early work in Freeman and Watkins, Science, 2002; & Aschwanden, Self Organized Criticality (SOC) in Astrophysics, Springer, 2011]. In part it resulted from the widespread approximate fractality seen elsewhere in nature. SOC was introduced by Bak et al [PRL, 1987] as a physical explanation of such widespread space-time fractality. SOC inspired the introduction into magnetospheric physics of "burst" diagnostics by Takalo [1993] & Consolini [1996]. These quantified events in a time series by "size" (integrated area above a fixed threshold) and "duration", and revealed a long tailed population of events across a broad range of sizes, subsequently also seen in solar wind drivers like Akasofu's epsilon function [Freeman et al, PRE & GRL, 2000]. Spatiotemporal bursts have an interest beyond SOC, however. Estimating the probability of a burst of a given size and duration bears directly on the problem of correlated extreme events, or "bunched black swans" [e.g. Watkins et al, EGU, 2011 presentation at the URL below]. With a view both to space physics and this wider context we here consider an interesting development of the burst idea made by Uritsky et al [GRL, 2001]. These authors adapted the spatiotemporal spreading exponent [e.g. Marro & Dickman, Nonequilibrium phase transitions in lattice models, 1999], calculating a superposed epoch average of surviving activity in bursts after their first excursion above a threshold. In a 1D time series, the 1-minute AL auroral index (averaged over 5 minutes), they found scaling behaviour up to ~ 2 hours. We investigate the relationships between exponents found by this method and other, more widely known exponents governing a fractal (or multifractal) time series such as the self-similarity exponent H and long-range dependence exponent d. We conclude by discussing the applications of these techniques to problems such as the forecasting the probability of a single short-lived large burst versus that of a long correlated sequence of more moderate exceedences above a threshold.
NASA Astrophysics Data System (ADS)
Gordon, John
2013-04-01
Geodiversity delivers or underpins many key ecosystem processes and services that deliver valuable benefits for society. With a growing recognition of the wider economic, social and environmental relevance of geodiversity, it is timely to consider the research requirements and priorities that are necessary to underpin a broader interdisciplinary approach to geodiversity that incorporates the links between natural and human systems in a changing world. A key challenge is to develop the scientific framework of geodiversity and at the same time to enhance the protection of geoheritage. Research that helps to support environmental policy and meet the wider needs of society for sustainable development and improved human wellbeing is fundamental both to improve the recognition of geodiversity and to demonstrate the wider relevance and value of geoheritage and geoconservation. Within this wider context, priorities for research include: 1) assessment of geoheritage and best-practice management of geosites for multiple uses including science, education and tourism; 2) evaluation of geodiversity and the ecosystem services it provides, both in economic and non-economic terms, to help build policy support and public awareness; 3) understanding the functional links between geodiversity and biodiversity across a range of spatial and temporal scales to help assess ecosystem sensitivity and inform management adaptations to climate change, particularly in dynamic environments such as the coast, river catchments and mountain areas; 4) providing a longer time perspective on ecosystem trends and services from palaeoenvironmental records; 5) applications of geodiversity in terrestrial and marine spatial planning.
Kim, Ga Ram; Shin, Jung Hee; Hahn, Soo Yeon; Ko, Eun Young; Oh, Young Lyun
2016-04-25
Warthin-like variant of papillary thyroid carcinoma (WVPTC) is a rare entity recently characterized. We evaluated ultrasonographic (US) features and clinical characteristics of WVPTC. Nine patients were diagnosed with WVPTC through surgery in our institution from May 2005 to January 2015. Eight of nine patients had available preoperative US images. A retrospective review of the US and clinical characteristics was performed. WVPTC compromised of 0.06% of 14,071 PTCs surgically confirmed. A mean age of nine patients was 53.2 years (range, 32-75 years). The mean nodule size of nine WVPTCs was 0.9 cm (range, 0.5-1.5 cm). Two patients showed central nodal metastasis and one patient with conventional PTC as an index tumor underwent central and lateral neck dissection. No one showed recurrence or distant metastasis during the follow-up period (mean, 4.6 years; range, 0.6-10 years). The most common US features of WVPTCs were solid composition (62.5%), hypoechogenicity (75%), and wider-than-tall shape (100%), respectively. Four (50%) of eight nodules showed well-defined margin and three (37.5%) of them had cystic component. One of eight resembled focal thyroiditis. Three nodules were considered as probably benign with US. All nine cases demonstrated underlying heterogeneous parenchymal echogenicity and accompanied chronic lymphocytic thyroiditis in permanent sections. Thyroid function tests in all patients were normal except for one with subclinical hypothyroidism. WVPTC is an uncommon subtype of PTC and has favorable prognosis, which can be misdiagnosed as a probably benign nodule or focal thyroiditis with US. All cases are associated with heterogeneous parenchyma in the background.
Di Fabio, Francesco; Alvarado, Carlos; Gologan, Adrian; Youssef, Emad; Voda, Linda; Mitmaker, Elliot; Beitel, Lenore K; Gordon, Philip H; Trifiro, Mark
2009-06-01
The X-linked human androgen receptor gene (AR) contains an exonic polymorphic trinucleotide CAG. The length of this encoded CAG tract inversely affects AR transcriptional activity. Colorectal carcinoma is known to express the androgen receptor, but data on somatic CAG repeat lengths variations in malignant and normal epithelial cells are still sporadic. Using laser capture microdissection (LCM), epithelial cells from colorectal carcinoma and normal-appearing mucosa were collected from the fresh tissue of eight consecutive male patients undergoing surgery (mean age, 70 y; range, 54-82). DNA isolated from each LCM sample underwent subsequent PCR and DNA sequencing to precisely determine AR CAG repeat lengths and the presence of microsatellite instability (MSI). Different AR CAG repeat lengths were observed in colorectal carcinoma (ranging from 0 to 36 CAG repeats), mainly in the form of multiple shorter repeat lengths. This genetic heterogeneity (somatic mosaicism) was also found in normal-appearing colorectal mucosa. Half of the carcinoma cases examined tended to have a higher number of AR CAG repeat lengths with a wider range of repeat size variation compared to normal mucosa. MSI carcinomas tended to have longer median AR CAG repeat lengths (n = 17) compared to microsatellite stable carcinomas (n = 14), although the difference was not significant (P = 0.31, Mann-Whitney test). Multiple unique somatic mutations of the AR CAG repeats occur in colorectal mucosa and in carcinoma, predominantly resulting in shorter alleles. Colorectal epithelial cells carrying AR alleles with shorter CAG repeat lengths may be more androgen-sensitive and therefore have a growth advantage.
Hidalgo-Galiana, A; Monge, M; Biron, D G; Canals, F; Ribera, I; Cieslak, A
2016-01-01
Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape.
Hidalgo-Galiana, A; Monge, M; Biron, D G; Canals, F; Ribera, I; Cieslak, A
2016-01-01
Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape. PMID:26328758
NASA Astrophysics Data System (ADS)
Gibbons, M. J.
1988-12-01
The impact of wave exposure on the meiofaunal communities colonising Gelidium pristoides, was examined on five shores around False Bay, South Africa. Under conditions of constant algal structure and mass, and in tufts with similar epiphyte and sediment loads, exposure had a profound impact on meiofaunal communities. Algae on sheltered shores supported significantly greater numbers of animals in the size range 63-280 μm (predominantly copepods, copepod nauplii and ostracods), while those on exposed shores supported a greater number of amphipods and bivalves. Total meiofaunal biomass per tuft remained constant irrespective of shore type. Differences between shores are discussed in terms of algal structure and animal size and morphology. Gelidium tufts are open-plan and offer little resistance to water movement; as the frond diameter is wider than the meiofauna are long, small animals are likely to be flushed more easily from exposed than sheltered shores. Differences in the abundance of permanent meiofauna between shores may, however, reflect ifferences in the organic content of sediments, although this was not examined. It is also suggested that meiofaunal communities on plants from different shores are influenced by the total algal and macrofaunal standing stocks, which act as banks of meiofauna and influence the regularity and magnitude of immigration. Extrapolating these data to the whole shore indicates that while the biomass of meiofauna may be greater on exposed than sheltered shores, the proportional contribution of meiofauna to total secondary production is greater under more sheltered conditions.
Hu, Jingyi; Shang, Ran; Heijman, Bas; Rietveld, Luuk
2015-09-01
Spent granular activated carbons (sGACs) for drinking water treatments were reused via pulverizing as low-cost adsorbents for micro-pollutant adsorption from a secondary treated wastewater effluent. The changes of physicochemical characteristics of the spent carbons in relation to the fresh carbons were determined and were correlated to the molecular properties of the respective GAC influents (i.e. a surface water and a groundwater). Pore size distribution analysis showed that the carbon pore volume decreased over a wider size range due to preloading by surface water, which contains a broader molecular weight distribution of organic matter in contrast to the groundwater. However, there was still considerable capacity available on the pulverized sGACs for atrazine adsorption in demineralized water and secondary effluent, and this was particularly the case for the groundwater spent GAC. However, as compared to the fresh counterparts, the decreased surface area and the induced surface acidic groups on the pulverized sGACs contributed both to the lower uptake and the more impeded adsorption kinetic of atrazine in the demineralized water. Nonetheless, the pulverized sGACs, especially the one preloaded by surface water, was less susceptible to adsorption competition in the secondary effluent, due to its negatively charged surface which can repulse the accessibility of the co-present organic matter. This suggests the reusability of the drinking water spent GACs for micro-pollutant adsorption in the treated wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.
Dellabianca, Natalia A.; Pierce, Graham J.; Raya Rey, Andrea; Scioscia, Gabriela; Miller, David L.; Torres, Mónica A.; Paso Viola, M. Natalia; Schiavini, Adrián C. M.
2016-01-01
Commerson’s dolphins (Cephalorhynchus c. commersonii) and Peale’s dolphins (Lagenorhynchus australis) are two of the most common species of cetaceans in the coastal waters of southwest South Atlantic Ocean. Both species are listed as Data Deficient by the IUCN, mainly due to the lack of information about population sizes and trends. The goal of this study was to build spatially explicit models for the abundance of both species in relation to environmental variables using data collected during eight scientific cruises along the Patagonian shelf. Spatial models were constructed using generalized additive models. In total, 88 schools (212 individuals) of Commerson’s dolphin and 134 schools (465 individuals) of Peale’s dolphin were recorded in 8,535 km surveyed. Commerson’s dolphin was found less than 60 km from shore; whereas Peale’s dolphins occurred over a wider range of distances from the coast, the number of animals sighted usually being larger near or far from the coast. Fitted models indicate overall abundances of approximately 22,000 Commerson’s dolphins and 20,000 Peale’s dolphins in the total area studied. This work provides the first large-scale abundance estimate for Peale’s dolphin in the Atlantic Ocean and an update of population size for Commerson’s dolphin. Additionally, our results contribute to baseline data on suitable habitat conditions for both species in southern Patagonia, which is essential for the implementation of adequate conservation measures. PMID:27783627
Marginal predation: do encounter or confusion effects explain the targeting of prey group edges?
Duffield, Callum; Ioannou, Christos C
2017-01-01
Marginal predation, also known as the edge effect, occurs when aggregations of prey are preferentially targeted on their periphery by predators and has long been established in many taxa. Two main processes have been used to explain this phenomenon, the confusion effect and the encounter rate between predators and prey group edges. However, it is unknown at what size a prey group needs to be before marginal predation is detectable and to what extent each mechanism drives the effect. We conducted 2 experiments using groups of virtual prey being preyed upon by 3-spined sticklebacks ( Gasterosteus aculeatus ) to address these questions. In Experiment 1, we show that group sizes do not need to be large for marginal predation to occur, with this being detectable in groups of 16 or more. In Experiment 2, we find that encounter rate is a more likely explanation for marginal predation than the confusion effect in this system. We find that while confusion does affect predatory behaviors (whether or not predators make an attack), it does not affect marginal predation. Our results suggest that marginal predation is a more common phenomenon than originally thought as it also applies to relatively small groups. Similarly, as marginal predation does not need the confusion effect to occur, it may occur in a wider range of predator-prey species pairings, for example those where the predators search for prey using nonvisual sensory modalities.
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.
NASA Astrophysics Data System (ADS)
Janebo, Maria H.; Houghton, Bruce F.; Thordarson, Thorvaldur; Bonadonna, Costanza; Carey, Rebecca J.
2018-05-01
The size distribution of the population of particles injected into the atmosphere during a volcanic explosive eruption, i.e., the total grain-size distribution (TGSD), can provide important insights into fragmentation efficiency and is a fundamental source parameter for models of tephra dispersal and sedimentation. Recent volcanic crisis (e.g. Eyjafjallajökull 2010, Iceland and Córdon Caulle 2011, Chile) and the ensuing economic losses, highlighted the need for a better constraint of eruption source parameters to be used in real-time forecasting of ash dispersal (e.g., mass eruption rate, plume height, particle features), with a special focus on the scarcity of published TGSD in the scientific literature. Here we present TGSD data associated with Hekla volcano, which has been very active in the last few thousands of years and is located on critical aviation routes. In particular, we have reconstructed the TGSD of the initial subplinian-Plinian phases of four historical eruptions, covering a range of magma composition (andesite to rhyolite), eruption intensity (VEI 4 to 5), and erupted volume (0.2 to 1 km3). All four eruptions have bimodal TGSDs with mass fraction of fine ash (<63 μm; m63) from 0.11 to 0.25. The two Plinian dacitic-rhyolitic Hekla deposits have higher abundances of fine ash, and hence larger m63 values, than their andesitic subplinian equivalents, probably a function of more intense and efficient primary fragmentation. Due to differences in plume height, this contrast is not seen in samples from individual sites, especially in the near field, where lapilli have a wider spatial coverage in the Plinian deposits. The distribution of pyroclast sizes in Plinian versus subplinian falls reflects competing influences of more efficient fragmentation (e.g., producing larger amounts of fine ash) versus more efficient particle transport related to higher and more vigorous plumes, displacing relatively coarse lapilli farther down the dispersal axis.
Interfacial material for solid oxide fuel cell
Baozhen, Li; Ruka, Roswell J.; Singhal, Subhash C.
1999-01-01
Solid oxide fuel cells having improved low-temperature operation are disclosed. In one embodiment, an interfacial layer of terbia-stabilized zirconia is located between the air electrode and electrolyte of the solid oxide fuel cell. The interfacial layer provides a barrier which controls interaction between the air electrode and electrolyte. The interfacial layer also reduces polarization loss through the reduction of the air electrode/electrolyte interfacial electrical resistance. In another embodiment, the solid oxide fuel cell comprises a scandia-stabilized zirconia electrolyte having high electrical conductivity. The scandia-stabilized zirconia electrolyte may be provided as a very thin layer in order to reduce resistance. The scandia-stabilized electrolyte is preferably used in combination with the terbia-stabilized interfacial layer. The solid oxide fuel cells are operable over wider temperature ranges and wider temperature gradients in comparison with conventional fuel cells.
Entanglement and asymmetric steering over two octaves of frequency difference
NASA Astrophysics Data System (ADS)
Olsen, M. K.
2017-12-01
The development of quantum technologies which use quantum states of the light field interacting with other systems creates a demand for entangled states spanning wide frequency ranges. In this work we analyze a parametric scheme of cascaded harmonic generation which promises to deliver bipartite entangled states in which the two modes are separated by two octaves in frequency. This scheme is potentially very useful for applications in quantum communication and computation networks as well as providing for quantum interfaces between a wider range of light and atomic ensembles than is presently practicable. It doubles the frequency range over which entanglement is presently available.
Anion-Cation Permeability Correlates with Hydrated Counterion Size in Glycine Receptor Channels
Sugiharto, Silas; Lewis, Trevor M.; Moorhouse, Andrew J.; Schofield, Peter R.; Barry, Peter H.
2008-01-01
The functional role of ligand-gated ion channels depends critically on whether they are predominantly permeable to cations or anions. However, these, and other ion channels, are not perfectly selective, allowing some counterions to also permeate. To address the mechanisms by which such counterion permeation occurs, we measured the anion-cation permeabilities of different alkali cations, Li+ Na+, and Cs+, relative to either Cl− or \\documentclass[10pt]{article} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{pmc} \\usepackage[Euler]{upgreek} \\pagestyle{empty} \\oddsidemargin -1.0in \\begin{document} \\begin{equation*}{\\mathrm{NO}}_{3}^{-}\\end{equation*}\\end{document} anions in both a wild-type glycine receptor channel (GlyR) and a mutant GlyR with a wider pore diameter. We hypothesized and showed that counterion permeation in anionic channels correlated inversely with an equivalent or effective hydrated size of the cation relative to the channel pore radius, with larger counterion permeabilities being observed in the wider pore channel. We also showed that the anion component of conductance was independent of the nature of the cation. We suggest that anions and counterion cations can permeate through the pore as neutral ion pairs, to allow the cations to overcome the large energy barriers resulting from the positively charged selectivity filter in small GlyR channels, with the permeability of such ion pairs being dependent on the effective hydrated diameter of the ion pair relative to the pore diameter. PMID:18708455
NASA Astrophysics Data System (ADS)
Mignani, Anna G.; Ciaccheri, Leonardo; Cimato, Antonio; Sani, Graziano; Smith, Peter R.
2004-03-01
Absorption spectroscopy and multi-angle scattering measurements in the visible spectral range are innovately used to analyze samples of extra virgin olive oils coming from selected areas of Tuscany, a famous Italian region for the production of extra virgin olive oil. The measured spectra are processed by means of the Principal Component Analysis method, so as to create a 3D map capable of clustering the Tuscan oils within the wider area of Italian extra virgin olive oils.
Kito, Keiji; Okada, Mitsuhiro; Ishibashi, Yuko; Okada, Satoshi; Ito, Takashi
2016-05-01
The accurate and precise absolute abundance of proteins can be determined using mass spectrometry by spiking the sample with stable isotope-labeled standards. In this study, we developed a strategy of hierarchical use of peptide-concatenated standards (PCSs) to quantify more proteins over a wider dynamic range. Multiple primary PCSs were used for quantification of many target proteins. Unique "ID-tag peptides" were introduced into individual primary PCSs, allowing us to monitor the exact amounts of individual PCSs using a "secondary PCS" in which all "ID-tag peptides" were concatenated. Furthermore, we varied the copy number of the "ID-tag peptide" in each PCS according to a range of expression levels of target proteins. This strategy accomplished absolute quantification over a wider range than that of the measured ratios. The quantified abundance of budding yeast proteins showed a high reproducibility for replicate analyses and similar copy numbers per cell for ribosomal proteins, demonstrating the accuracy and precision of this strategy. A comparison with the absolute abundance of transcripts clearly indicated different post-transcriptional regulation of expression for specific functional groups. Thus, the approach presented here is a faithful method for the absolute quantification of proteomes and provides insights into biological mechanisms, including the regulation of expressed protein abundance. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
ERIC Educational Resources Information Center
Rubino, Antonia; Cruickshank, Ken
2016-01-01
Australian research on immigrant languages has paid little attention to interactional approaches to language alternation as identity construction, and sites other than the family and the mainstream school. We argue for the need of studies that take into account a wider range of sites, in particular "community" sites, and adopt…
ERIC Educational Resources Information Center
Gillespie, Simon
2017-01-01
Educating a diverse student population is a core principle of international school education. Historically, many international schools have had admissions policies that excluded students with special learning needs. However, admission policies have changed to require more inclusiveness and school support for a wider range of students and for…
System for corrosion monitoring in pipeline applying fuzzy logic mathematics
NASA Astrophysics Data System (ADS)
Kuzyakov, O. N.; Kolosova, A. L.; Andreeva, M. A.
2018-05-01
A list of factors influencing corrosion rate on the external side of underground pipeline is determined. Principles of constructing a corrosion monitoring system are described; the system performance algorithm and program are elaborated. A comparative analysis of methods for calculating corrosion rate is undertaken. Fuzzy logic mathematics is applied to reduce calculations while considering a wider range of corrosion factors.
Darius M. Adams; Ralph J. Alig; J.M. Callaway; Bruce A. McCarl; Steven M. Winnett
1996-01-01
The Forest and Agricultural Sector Optimization Model (FASOM) is a dynamic, nonlinear programming model of the forest and agricultural sectors in the United States. The FASOM model initially was developed to evaluate welfare and market impacts of alternative policies for sequestering carbon in trees but also has been applied to a wider range of forest and agricultural...
How Organisations Are Using Blended E-Learning to Deliver More Flexible Approaches to Trade Training
ERIC Educational Resources Information Center
Callan, Victor James; Johnston, Margaret Alison; Poulsen, Alison Louise
2015-01-01
Training organisations are being asked to respond to the growing levels of diversity around the contexts for training and to examine a wider range of training solutions than in the past. This research investigates how training organisations in Australia are using blended forms of e-learning to provide more responsive, flexible and innovative…
Deeper Learning: Improving Student Outcomes for College, Career, and Civic Life. Policy Brief
ERIC Educational Resources Information Center
Bitter, Catherine; Loney, Emily
2015-01-01
The Issue: To prepare for the demands of postsecondary education and the workforce, students need to master content and build skills that allow them to collaborate with others, and then apply that knowledge to new situations. Students will be able to access a wider range of opportunities in college, career, and civic life if they possess the…
A Longitudinal Study of Post-School Provision for Irish School-Leavers with Intellectual Disability
ERIC Educational Resources Information Center
McConkey, Roy; Kelly, Fionnola; Craig, Sarah; Keogh, Fiona
2017-01-01
Background: In recent years, efforts have been made to improve the transition of pupils with intellectual disabilities to adult services and to offer a wider range of choices. However, there have been few longitudinal studies to monitor the services provided to young adults post-school. This case study in the Republic of Ireland identified the…
Assessing the Impact of Regeneration Spending: Lessons from the United Kingdom and the Wider World
ERIC Educational Resources Information Center
Potts, David
2008-01-01
The government increased the funding for regional development agencies to 2.3 billion British Pounds in 2007/8, yet hard evidence on the effectiveness of the spending is difficult to find. Techniques for valuing benefits in difficult areas have existed for many years. They range from the hedonic methods and contingent valuation studies of…
The Library of Birmingham Project: Lifelong Learning for the Digital Age
ERIC Educational Resources Information Center
Blewitt, John; Gambles, Brian
2010-01-01
The Library of Birmingham (LoB) is a 193 million British pounds project designed to provide a new space for lifelong learning and knowledge growth, a physical and virtual portal for Birmingham's citizens to the wider world. In cooperation with a range of private, public, and third-sector bodies, as well as individual citizens, the library, due to…
Responding to Self-Harm: A Documentary Analysis of Agency Policy and Procedure
ERIC Educational Resources Information Center
Paul, Sally; Hill, Malcolm
2013-01-01
This paper reports on the findings of a documentary analysis of policies and procedures relating to self-harm from a range of organisations working with young people in the UK. It identifies the extent to which policies and/or procedures relating to self-harm are available for service providers and offers a wider understanding of the concepts of…
ERIC Educational Resources Information Center
Soler, Josep; Björkman, Beyza; Kuteeva, Maria
2018-01-01
As universities seek to become more international, their need to engage with a wider range of languages, particularly English, seems more prominent. At the same time, universities are also regarded by many stakeholders as key institutions to preserve a given national language and culture. This apparent tension makes universities a fruitful ground…
ERIC Educational Resources Information Center
Cretchley, Patricia
2009-01-01
The Australian Federal Government and Australian universities have embarked on a bid to raise the profile of learning and teaching (L&T) in universities. Current strategies include increased funding of competitive grants for L&T projects, a wider range of teaching awards and fellowships and a controversial new national competitive Learning…
Dale G. Brockway; Kenneth W. Outcalt
2017-01-01
Though longleaf pine (Pinus palustris Mill.) forests have been primarily managed with even-aged methods, interest is increasing in uneven-aged systems, as a means of achieving a wider range of stewardship goals. Selection silviculture has been practiced on a limited scale in longleaf pine, but difficulty with using traditional approaches and...
ERIC Educational Resources Information Center
Plane, Karen
In a competitive market training economy, vocational education and training (VET) and small business in Australia face a number of challenges. They need to qualify the extent of lifelong learning skills being used in the small firm workplace, define the range of learning partnerships both within VET and the wider informal learning community in…
ERIC Educational Resources Information Center
Osborne, Lisa A.; Reed, Phil
2009-01-01
Two 9- to 10-month-Iong studies (N = 137) examined the interaction between parenting stress and behavior problems in children with autistic spectrum disorders (ASDs). Study 1 focused on very young children, and Study 2 employed a wider range of child ages; both studies assessed these factors at 2 points in time. The researchers noted a strong…
ERIC Educational Resources Information Center
Qingquan, Ni; Chatupote, Monta; Teo, Adisa
2008-01-01
This article focused on the investigation of the differences in the frequency of language learning strategy use by successful and unsuccessful first-year students of a Chinese university. The study found that successful students used a wider range of learning strategies for EFL learning significantly more frequently than unsuccessful students. It…
Defect-enhanced void filling and novel filled phases of open-structure skutterudites
Xi, Lili; Qiu, Yuting; Shi, Xun; ...
2015-05-14
Here, we report the design of novel filled CoSb 3 skutterudite phases based on a combination of filling and Sb-substituted Ga/In defects. Ga/In doped skutterudite phases with Li-, Nd-, and Sm-fillings can be formed via this strategy, which can have relatively wider ranges of carrier concentration than other conventional filled skutterudite phases.
ERIC Educational Resources Information Center
Goatman, Mike; Moody, Louise
2014-01-01
There are currently a wide range of Higher Education Industrial Design courses available in the UK. In the present era, a wider breadth of narrative has developed within the subject, and as a result the content of industrial design educational offerings varies considerably. The paper assesses the industry view of Industrial Design as a discipline…
Rodney J. Keenan; David Lamb; John Parrotta
1999-01-01
Management of tropical timber plantations is generally based on a single-product output, high-input model, often using an exotic species that has been successfully used for plantation timber production in many temperate regions. This intensive model may be appropriate in areas designated solely for wood production but where the aim is to produce a wider range...
ERIC Educational Resources Information Center
Lyon, Edward G.; Bunch, George C.; Shaw, Jerome M.
2012-01-01
Science performance assessments (SPAs) are designed to elicit a wider range of scientific knowledge and abilities than ordinarily measured by more traditional paper-and-pencil tests. To engage in SPAs and thus demonstrate abilities such as scientific inquiry, students must interact with various participants and communicate in a variety of ways.…
The Role of Silence in Teaching and Learning
ERIC Educational Resources Information Center
Schultz, Katherine
2013-01-01
The author's first teaching position was as a 4th and 5th grade teacher at a school in Philadelphia. There, she learned the Quaker value of adding silence and periods of reflection to her teaching to provide a wider range of students with the opportunity to participate in classroom discussions. Later, a focus on silence as a teaching strategy led…
ERIC Educational Resources Information Center
Nagtalon-Ramos, Jamille Kristine
2017-01-01
Although Filipino and Filipino American nurses represent an impressive share of the nursing workforce, they are not well represented in advanced practice, faculty, and executive leadership positions. Obtaining a graduate degree in nursing has the potential to open a wider range of opportunities to meet the healthcare demands of a population that…
Math Across the Community College Curriculum (MAC3): A Successful Path to Quantitative Literacy
ERIC Educational Resources Information Center
Hillyard, Cinnamon; Korey, Jane; Leoni, Deann; Hartzler, Rebecca
2010-01-01
In recent years, mathematical and quantitative arguments have become prominent in the media as well as in politics, business, and science conversations. This has led to multiple calls for mathematics to be more accessible and meaningful to a wider range of the population (AMATYC, 2006; Cerrito, 1996; Cheney, 1989; Cohen, 1982; College Board, 1983;…
ERIC Educational Resources Information Center
Yue, Siwei; Wang, Xuefei
2014-01-01
Based on a corpus of 296 authentic business emails produced in computer-mediated business communication from 7 Chinese international trade enterprises, this paper addresses the language strategy applied in CMC (Computer-mediated Communication) by examining the use of hedges. With the emergence of internet, a wider range of hedges are applied…
On temporal stochastic modeling of precipitation, nesting models across scales
NASA Astrophysics Data System (ADS)
Paschalis, Athanasios; Molnar, Peter; Fatichi, Simone; Burlando, Paolo
2014-01-01
We analyze the performance of composite stochastic models of temporal precipitation which can satisfactorily reproduce precipitation properties across a wide range of temporal scales. The rationale is that a combination of stochastic precipitation models which are most appropriate for specific limited temporal scales leads to better overall performance across a wider range of scales than single models alone. We investigate different model combinations. For the coarse (daily) scale these are models based on Alternating renewal processes, Markov chains, and Poisson cluster models, which are then combined with a microcanonical Multiplicative Random Cascade model to disaggregate precipitation to finer (minute) scales. The composite models were tested on data at four sites in different climates. The results show that model combinations improve the performance in key statistics such as probability distributions of precipitation depth, autocorrelation structure, intermittency, reproduction of extremes, compared to single models. At the same time they remain reasonably parsimonious. No model combination was found to outperform the others at all sites and for all statistics, however we provide insight on the capabilities of specific model combinations. The results for the four different climates are similar, which suggests a degree of generality and wider applicability of the approach.
SEAL Studies of Variant Blanket Concepts and Materials
NASA Astrophysics Data System (ADS)
Cook, I.; Taylor, N. P.; Forty, C. B. A.; Han, W. E.
1997-09-01
Within the European SEAL ( Safety and Environmental Assessment of fusion power, Long-term) program, safety and environmental assessments have been performed which extend the results of the earlier SEAFP (Safety and Environmental Assessment of Fusion Power) program to a wider range of blanket designs and material choices. The four blanket designs analysed were those which had been developed within the Blanket program of the European Fusion Programme. All four are based on martensitic steel as structural material, and otherwise may be summarized as: water-cooled lithium-lead; dual-cooled lithium-lead; helium-cooled lithium silicate (BOT geometry); helium-cooled lithium aluminate (or zirconate) (BIT geometry). The results reveal that all the blankets show the favorable S&E characteristics of fusion, though there are interesting and significant differences between them. The key results are described. Assessments have also been performed of a wider range of materials than was considered in SEAFP. These were: an alternative vanadium alloy, an alternative low-activation martensitic steel, titanium-aluminum intermetallic, and SiC composite. Assessed impurities were included in the compositions, and these had very important effects upon some of the results. Key results impacting upon accident characteristics, recycling, and waste management are described.
Burners and combustion apparatus for carbon nanomaterial production
Alford, J. Michael; Diener, Michael D; Nabity, James; Karpuk, Michael
2013-02-05
The invention provides improved burners, combustion apparatus, and methods for carbon nanomaterial production. The burners of the invention provide sooting flames of fuel and oxidizing gases. The condensable products of combustion produced by the burners of this invention produce carbon nanomaterials including without limitation, soot, fullerenic soot, and fullerenes. The burners of the invention do not require premixing of the fuel and oxidizing gases and are suitable for use with low vapor pressure fuels such as those containing substantial amounts of polyaromatic hydrocarbons. The burners of the invention can operate with a hot (e.g., uncooled) burner surface and require little, if any, cooling or other forms of heat sinking. The burners of the invention comprise one or more refractory elements forming the outlet of the burner at which a flame can be established. The burners of the invention provide for improved flame stability, can be employed with a wider range of fuel/oxidizer (e.g., air) ratios and a wider range of gas velocities, and are generally more efficient than burners using water-cooled metal burner plates. The burners of the invention can also be operated to reduce the formation of undesirable soot deposits on the burner and on surfaces downstream of the burner.
Burners and combustion apparatus for carbon nanomaterial production
Alford, J. Michael; Diener, Michael D.; Nabity, James; Karpuk, Michael
2007-10-09
The invention provides improved burners, combustion apparatus, and methods for carbon nanomaterial production. The burners of the invention provide sooting flames of fuel and oxidizing gases. The condensable products of combustion produced by the burners of this invention produce carbon nanomaterials including without limitation, soot, fullerenic soot, and fullerenes. The burners of the invention do not require premixing of the fuel and oxidizing gases and are suitable for use with low vapor pressure fuels such as those containing substantial amounts of polyaromatic hydrocarbons. The burners of the invention can operate with a hot (e.g., uncooled) burner surface and require little, if any, cooling or other forms of heat sinking. The burners of the invention comprise one or more refractory elements forming the outlet of the burner at which a flame can be established. The burners of the invention provide for improved flame stability, can be employed with a wider range of fuel/oxidizer (e.g., air) ratios and a wider range of gas velocities, and are generally more efficient than burners using water-cooled metal burner plates. The burners of the invention can also be operated to reduce the formation of undesirable soot deposits on the burner and on surfaces downstream of the burner.
Runemark, Anna; Sagonas, Kostas; Svensson, Erik I
2015-08-01
Although rapid evolution of body size on islands has long been known, the ecological mechanisms behind this island phenomenon remain poorly understood. Diet is an important selective pressure for morphological divergence. Here we investigate if selection for novel diets has contributed to the multiple independent cases of island gigantism in the Skyros wall lizard (Podarcis gaigeae) and if diet, predation, or both factors best explain island gigantism. We combined data on body size, shape, bite force, and realized and available diets to address this. Several lines of evidence suggest that diet has contributed to the island gigantism. The larger islet lizards have relatively wider heads and higher bite performance in relation to mainland lizards than would be expected from size differences alone. The proportions of consumed and available hard prey are higher on islets than mainland localities, and lizard body size is significantly correlated with the proportion of hard prey. Furthermore, the main axis of divergence in head shape is significantly correlated with dietary divergence. Finally, a model with only diet and one including diet and predation regime explain body size divergence equally well. Our results suggest that diet is an important ecological factor behind insular body size divergence, but could be consistent with an additional role for predation.
Dalton, Hillary A; Wood, Benjamin J; Widowski, Tina M; Guerin, Michele T; Torrey, Stephanie
2017-01-01
The objective of this study was to assess beak shape variation in domestic turkeys (Meleagris gallopavo) and determine the effects of age, sex, and beak size on beak shape variation using geometric morphometrics. Dorsal and right lateral images were taken of 2442 turkeys at 6 and 18.5 weeks of age. Landmarks were digitized in tpsDig in three analyses of the dorsal upper mandible, lateral upper mandible, and lateral lower mandible shape of each turkey at both ages. The coordinate data were then subjected to a principal components analysis (PCA), multivariate regression, and a canonical variates analysis (CVA) with a Procrustes ANOVA in MorphoJ. For the dorsal images, three principal components (PCs) showed beak shape variation ranged from long, narrow, and pointed to short, wide, and blunt upper mandibles at both ages (6 weeks: 95.36%, 18.5 weeks: 92.21%). Three PCs showed the lateral upper mandible shape variation ranged from long, wide beaks with long, curved beak tips to short, narrow beaks with short, pointed beak tips at both ages (6 weeks: 94.91%, 18.5 weeks: 94.33%). Three PCs also explained 97.80% (6 weeks) and 97.11% (18.5 weeks) of the lateral lower mandible shape variation ranging from wide and round to narrow and thin lower mandibles with superior/inferior beak tip shifts. Beak size accounted for varying proportions of the beak shape variation (0.96-54.76%; P < 0.0001) in the three analyses of each age group. For all the analyses, the CVA showed sexual dimorphism in beak shape (P < 0.0001) with female upper mandibles appearing wider and blunter dorsally with long, curved beak tips laterally. Whereas male turkey upper mandibles had a narrow, pointed dorsal appearance and short, pointed beak tips laterally. Future applications of beak shape variability could have a genetic and welfare value by incorporating beak shape variation to select for specific turkey beak phenotypes as an alternative to beak treatment.
Current trends and future directions in flower development research.
Scutt, Charlie P; Vandenbussche, Michiel
2014-11-01
Flowers, the reproductive structures of the approximately 400 000 extant species of flowering plants, exist in a tremendous range of forms and sizes, mainly due to developmental differences involving the number, arrangement, size and form of the floral organs of which they consist. However, this tremendous diversity is underpinned by a surprisingly robust basic floral structure in which a central group of carpels forms on an axis of determinate growth, almost invariably surrounded by two successive zones containing stamens and perianth organs, respectively. Over the last 25 years, remarkable progress has been achieved in describing the molecular mechanisms that control almost all aspects of flower development, from the phase change that initiates flowering to the final production of fruits and seeds. However, this work has been performed almost exclusively in a small number of eudicot model species, chief among which is Arabidopsis thaliana. Studies of flower development must now be extended to a much wider phylogenetic range of flowering plants and, indeed, to their closest living relatives, the gymnosperms. Studies of further, more wide-ranging models should provide insights that, for various reasons, cannot be obtained by studying the major existing models alone. The use of further models should also help to explain how the first flowering plants evolved from an unknown, although presumably gymnosperm-like ancestor, and rapidly diversified to become the largest major plant group and to dominate the terrestrial flora. The benefits for society of a thorough understanding of flower development are self-evident, as human life depends to a large extent on flowering plants and on the fruits and seeds they produce. In this preface to the Special Issue, we introduce eleven articles on flower development, representing work in both established and further models, including gymnosperms. We also present some of our own views on current trends and future directions of the flower development field. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Cameron, Skye F; Wheatley, Rebecca; Wilson, Robbie S
2018-07-01
Studies of sexual selection primarily focus on morphological traits such as body size and secondary trait dimorphism, with less attention been given to the functional differences between the sexes and even more so their thermal performance capacities. Each sex may benefit from possessing different thermal performance capacities that would allow them to maximise their fitness relative to their different reproductive roles; especially when performances are closely related to reproductive success. Here, we examine sexual divergence in thermal sensitivities of performance across three populations of the Asian house gecko (Hemidactylus frenatus) over an extensive latitudinal cline. Using analyses of the thermal sensitivity of routine activity, bite force and sprint speed, we explored whether: (i) males and females differed in their optimal temperatures for performance, (ii) the sexes differed in their thermal sensitivities of performance, and (iii) the degree of sexual divergence in thermal sensitivity varied among the populations. Because male H. frenatus are highly aggressive and frequently engage in combat to gain territories and mating opportunities, we expected males would be active over a wider range of temperatures than females and this would favour broad thermal sensitivity curves for males. In addition, we expected a greater divergence between the sexes in thermal sensitivities for the temperate populations that experience greater daily and seasonal thermal variation. We found that males were more active, and had greater bite forces and faster sprint speeds than females, independent of body size. In addition, we found differences between the sexes in thermal sensitivities for the tropical population; female H. frenatus were less active and possessed lower sprint speeds at higher temperatures than males. Although H. frenatus from the most variable thermal environments also displayed the broadest thermal performance range, it was the more stable tropical population that exhibited the greatest divergence between the sexes in thermal sensitivity of performance. The divergence in thermal physiology that we detected between the sexes of H. frenatus is consistent with the idea that males will derive mating and territorial advantages for maintaining function over a broader range of temperatures.
Widowski, Tina M.; Guerin, Michele T.
2017-01-01
The objective of this study was to assess beak shape variation in domestic turkeys (Meleagris gallopavo) and determine the effects of age, sex, and beak size on beak shape variation using geometric morphometrics. Dorsal and right lateral images were taken of 2442 turkeys at 6 and 18.5 weeks of age. Landmarks were digitized in tpsDig in three analyses of the dorsal upper mandible, lateral upper mandible, and lateral lower mandible shape of each turkey at both ages. The coordinate data were then subjected to a principal components analysis (PCA), multivariate regression, and a canonical variates analysis (CVA) with a Procrustes ANOVA in MorphoJ. For the dorsal images, three principal components (PCs) showed beak shape variation ranged from long, narrow, and pointed to short, wide, and blunt upper mandibles at both ages (6 weeks: 95.36%, 18.5 weeks: 92.21%). Three PCs showed the lateral upper mandible shape variation ranged from long, wide beaks with long, curved beak tips to short, narrow beaks with short, pointed beak tips at both ages (6 weeks: 94.91%, 18.5 weeks: 94.33%). Three PCs also explained 97.80% (6 weeks) and 97.11% (18.5 weeks) of the lateral lower mandible shape variation ranging from wide and round to narrow and thin lower mandibles with superior/inferior beak tip shifts. Beak size accounted for varying proportions of the beak shape variation (0.96–54.76%; P < 0.0001) in the three analyses of each age group. For all the analyses, the CVA showed sexual dimorphism in beak shape (P < 0.0001) with female upper mandibles appearing wider and blunter dorsally with long, curved beak tips laterally. Whereas male turkey upper mandibles had a narrow, pointed dorsal appearance and short, pointed beak tips laterally. Future applications of beak shape variability could have a genetic and welfare value by incorporating beak shape variation to select for specific turkey beak phenotypes as an alternative to beak treatment. PMID:28934330
Khandelia, Piyush; Yap, Karen; Makeyev, Eugene V
2011-08-02
Sequence-specific gene silencing by short hairpin (sh) RNAs has recently emerged as an indispensable tool for understanding gene function and a promising avenue for drug discovery. However, a wider biomedical use of this approach is hindered by the lack of straightforward methods for achieving uniform expression of shRNAs in mammalian cell cultures. Here we report a high-efficiency and low-background (HILO) recombination-mediated cassette exchange (RMCE) technology that yields virtually homogeneous cell pools containing doxycycline-inducible shRNA elements in a matter of days and with minimal efforts. To ensure immediate utility of this approach for a wider research community, we modified 11 commonly used human (A549, HT1080, HEK293T, HeLa, HeLa-S3, and U2OS) and mouse (CAD, L929, N2a, NIH 3T3, and P19) cell lines to be compatible with the HILO-RMCE process. Because of its technical simplicity and cost efficiency, the technology will be advantageous for both low- and high-throughput shRNA experiments. We also provide evidence that HILO-RMCE will facilitate a wider range of molecular and cell biology applications by allowing one to rapidly engineer cell populations expressing essentially any transgene of interest.
Streamlined platform for short hairpin RNA interference and transgenesis in cultured mammalian cells
Khandelia, Piyush; Yap, Karen; Makeyev, Eugene V.
2011-01-01
Sequence-specific gene silencing by short hairpin (sh) RNAs has recently emerged as an indispensable tool for understanding gene function and a promising avenue for drug discovery. However, a wider biomedical use of this approach is hindered by the lack of straightforward methods for achieving uniform expression of shRNAs in mammalian cell cultures. Here we report a high-efficiency and low-background (HILO) recombination-mediated cassette exchange (RMCE) technology that yields virtually homogeneous cell pools containing doxycycline-inducible shRNA elements in a matter of days and with minimal efforts. To ensure immediate utility of this approach for a wider research community, we modified 11 commonly used human (A549, HT1080, HEK293T, HeLa, HeLa-S3, and U2OS) and mouse (CAD, L929, N2a, NIH 3T3, and P19) cell lines to be compatible with the HILO-RMCE process. Because of its technical simplicity and cost efficiency, the technology will be advantageous for both low- and high-throughput shRNA experiments. We also provide evidence that HILO-RMCE will facilitate a wider range of molecular and cell biology applications by allowing one to rapidly engineer cell populations expressing essentially any transgene of interest. PMID:21768390
2012-01-01
Background To explain eyespot colour-pattern determination in butterfly wings, the induction model has been discussed based on colour-pattern analyses of various butterfly eyespots. However, a detailed structural analysis of eyespots that can serve as a foundation for future studies is still lacking. In this study, fundamental structural rules related to butterfly eyespots are proposed, and the induction model is elaborated in terms of the possible dynamics of morphogenic signals involved in the development of eyespots and parafocal elements (PFEs) based on colour-pattern analysis of the nymphalid butterfly Junonia almana. Results In a well-developed eyespot, the inner black core ring is much wider than the outer black ring; this is termed the inside-wide rule. It appears that signals are wider near the focus of the eyespot and become narrower as they expand. Although fundamental signal dynamics are likely to be based on a reaction-diffusion mechanism, they were described well mathematically as a type of simple uniformly decelerated motion in which signals associated with the outer and inner black rings of eyespots and PFEs are released at different time points, durations, intervals, and initial velocities into a two-dimensional field of fundamentally uniform or graded resistance; this produces eyespots and PFEs that are diverse in size and structure. The inside-wide rule, eyespot distortion, structural differences between small and large eyespots, and structural changes in eyespots and PFEs in response to physiological treatments were explained well using mathematical simulations. Natural colour patterns and previous experimental findings that are not easily explained by the conventional gradient model were also explained reasonably well by the formal mathematical simulations performed in this study. Conclusions In a mode free from speculative molecular interactions, the present study clarifies fundamental structural rules related to butterfly eyespots, delineates a theoretical basis for the induction model, and proposes a mathematically simple mode of long-range signalling that may reflect developmental mechanisms associated with butterfly eyespots. PMID:22409965
Otaki, Joji M
2012-03-13
To explain eyespot colour-pattern determination in butterfly wings, the induction model has been discussed based on colour-pattern analyses of various butterfly eyespots. However, a detailed structural analysis of eyespots that can serve as a foundation for future studies is still lacking. In this study, fundamental structural rules related to butterfly eyespots are proposed, and the induction model is elaborated in terms of the possible dynamics of morphogenic signals involved in the development of eyespots and parafocal elements (PFEs) based on colour-pattern analysis of the nymphalid butterfly Junonia almana. In a well-developed eyespot, the inner black core ring is much wider than the outer black ring; this is termed the inside-wide rule. It appears that signals are wider near the focus of the eyespot and become narrower as they expand. Although fundamental signal dynamics are likely to be based on a reaction-diffusion mechanism, they were described well mathematically as a type of simple uniformly decelerated motion in which signals associated with the outer and inner black rings of eyespots and PFEs are released at different time points, durations, intervals, and initial velocities into a two-dimensional field of fundamentally uniform or graded resistance; this produces eyespots and PFEs that are diverse in size and structure. The inside-wide rule, eyespot distortion, structural differences between small and large eyespots, and structural changes in eyespots and PFEs in response to physiological treatments were explained well using mathematical simulations. Natural colour patterns and previous experimental findings that are not easily explained by the conventional gradient model were also explained reasonably well by the formal mathematical simulations performed in this study. In a mode free from speculative molecular interactions, the present study clarifies fundamental structural rules related to butterfly eyespots, delineates a theoretical basis for the induction model, and proposes a mathematically simple mode of long-range signalling that may reflect developmental mechanisms associated with butterfly eyespots.
Jiang, Xueliang; Yang, Zhen; Wang, Zhijie; Zhang, Fuqing; You, Feng
2018-01-01
Barium titanate/nitrile butadiene rubber (BT/NBR) and polyurethane (PU) foam were combined to prepare a sound-absorbing material with an alternating multilayered structure. The effects of the cell size of PU foam and the alternating unit number on the sound absorption property of the material were investigated. The results show that the sound absorption efficiency at a low frequency increased when decreasing the cell size of PU foam layer. With the increasing of the alternating unit number, the material shows the sound absorption effect in a wider bandwidth of frequency. The BT/NBR-PU foam composites with alternating multilayered structure have an excellent sound absorption property at low frequency due to the organic combination of airflow resistivity, resonance absorption, and interface dissipation. PMID:29565321
Jiang, Xueliang; Yang, Zhen; Wang, Zhijie; Zhang, Fuqing; You, Feng; Yao, Chu
2018-03-22
Barium titanate/nitrile butadiene rubber (BT/NBR) and polyurethane (PU) foam were combined to prepare a sound-absorbing material with an alternating multilayered structure. The effects of the cell size of PU foam and the alternating unit number on the sound absorption property of the material were investigated. The results show that the sound absorption efficiency at a low frequency increased when decreasing the cell size of PU foam layer. With the increasing of the alternating unit number, the material shows the sound absorption effect in a wider bandwidth of frequency. The BT/NBR-PU foam composites with alternating multilayered structure have an excellent sound absorption property at low frequency due to the organic combination of airflow resistivity, resonance absorption, and interface dissipation.
NASA Technical Reports Server (NTRS)
Fymat, A. L.; Smith, C. B.
1979-01-01
It is shown that the inverse analytical solutions, provided separately by Fymat and Box-McKellar, for reconstructing particle size distributions from remote spectral transmission measurements under the anomalous diffraction approximation can be derived using a cosine and a sine transform, respectively. Sufficient conditions of validity of the two formulas are established. Their comparison shows that the former solution is preferable to the latter in that it requires less a priori information (knowledge of the particle number density is not needed) and has wider applicability. For gamma-type distributions, and either a real or a complex refractive index, explicit expressions are provided for retrieving the distribution parameters; such expressions are, interestingly, proportional to the geometric area of the polydispersion.
Dosimetric studies of cadmium free alloy used in compensator based intensity modulated radiotherapy
NASA Astrophysics Data System (ADS)
Kaushik, Sandeep; Punia, Rajesh; Tyagi, Atul; Singh, Mann P.
2017-10-01
Aim of this study was to investigate dosimetric properties of cadmium free alloy which is used in compensator based intensity modulated radiotherapy (cIMRT). A mixture of lead, bismuth and tin was used to prepare the alloy whose melting point is 90-95 °C. Slabs of different thicknesses ranging from 0.71 cm to 6.14 cm were prepared. Density of alloy was measured by Archimedes' principle using water. For six megavolt (6 MV) photon beam energy transmission, linear effective attenuation coefficient (μeff), tissue phantom ratio (TPR1020), beam hardening, surface dose (Ds), percentage depth dose (PDD) and effect of scatter has been measured and analyzed for different field sizes and different thickness of compensator. Effect of extended source to detector distance (SDD) on transmissions and μeff was measured. The density of alloy was found to be 9.5456 g/cm3. At SDD of 100 cm, μeff was observed 0.4253 cm-1 for a field size of 10×10 cm 2. Calculated TPR1020 was found to be within 3% of experimental TPR1020 . It was found to be increasing with increasing thickness of compensator. Ds was found to decrease with thickness of compensator and increase with wider collimator opening due to increased scattered dose. Compensator slabs of 1 cm, 1.98 cm and 4.16 cm decreased surface dose by 4.2%, 6.1% and 9.5% respectively for a field size of 10×10 cm2 at 100 cm SDD. For small field size of 3×3 cm2 and 5×5 cm2 PDDs are increased from 3.0% to 5.5% of open beam PDDs as compensator thickness increased from 1 cm to 6.14 cm at a depth of 10 cm in water while variation in PDD is insignificant in for larger field sizes 10×10 cm2 to 20×20 cm2. A high degree of intensity modulation is essential in cIMRT and it can be achieved with this compensator material. Dosimetric properties analyzed in this study establish this alloy as a reliable, reusable, optimally dense and cost effective compensator material.
Advanced Ceramics from Preceramic Polymers Modified at the Nano-Scale: A Review.
Bernardo, Enrico; Fiocco, Laura; Parcianello, Giulio; Storti, Enrico; Colombo, Paolo
2014-03-06
Preceramic polymers, i.e. , polymers that are converted into ceramics upon heat treatment, have been successfully used for almost 40 years to give advanced ceramics, especially belonging to the ternary SiCO and SiCN systems or to the quaternary SiBCN system. One of their main advantages is the possibility of combining the shaping and synthesis of ceramics: components can be shaped at the precursor stage by conventional plastic-forming techniques, such as spinning, blowing, injection molding, warm pressing and resin transfer molding, and then converted into ceramics by treatments typically above 800 °C. The extension of the approach to a wider range of ceramic compositions and applications, both structural and thermo-structural (refractory components, thermal barrier coatings) or functional (bioactive ceramics, luminescent materials), mainly relies on modifications of the polymers at the nano-scale, i.e. , on the introduction of nano-sized fillers and/or chemical additives, leading to nano-structured ceramic components upon thermal conversion. Fillers and additives may react with the main ceramic residue of the polymer, leading to ceramics of significant engineering interest (such as silicates and SiAlONs), or cause the formation of secondary phases, significantly affecting the functionalities of the polymer-derived matrix.
Parreira de Castro, Diego Marcel; Reis de Carvalho, Débora; Pompeu, Paulo dos Santos; Moreira, Marcelo Zacharias; Nardoto, Gabriela Bielefeld; Callisto, Marcos
2016-01-01
It is well recognized that assemblage structure of stream macroinvertebrates changes with alterations in catchment or local land use. Our objective was to understand how the trophic ecology of benthic macroinvertebrate assemblages responds to land use changes in tropical streams. We used the isotope methodology to assess how energy flow and trophic relations among macroinvertebrates were affected in environments affected by different land uses (natural cover, pasture, sugar cane plantation). Macroinvertebrates were sampled and categorized into functional feeding groups, and available trophic resources were sampled and evaluated for the isotopic composition of 13C and 15N along streams located in the Cerrado (neotropical savanna). Streams altered by pasture or sugar cane had wider and more overlapped trophic niches, which corresponded to more generalist feeding habits. In contrast, trophic groups in streams with native vegetation had narrower trophic niches with smaller overlaps, suggesting greater specialization. Pasture sites had greater ranges of resources exploited, indicating higher trophic diversity than sites with natural cover and sugar cane plantation. We conclude that agricultural land uses appears to alter the food base and shift macroinvertebrate assemblages towards more generalist feeding behaviors and greater overlap of the trophic niches. PMID:26934113
Non-destructive plant health sensing using absorption spectroscopy
NASA Technical Reports Server (NTRS)
Bledsoe, Jim; Manukian, Ara; Pearce, Michael; Weiss, Lee
1988-01-01
The sensor group of the 1988 EGM 4001 class, working on NASA's Controlled Ecological Life Support Systems (CELSS) project, investigated many different plant health indicators and the technologies used to test them. The project selected by the group was to measure chlorophyll levels using absorption spectroscopy. The spectrometer measures the amount of chlorophyll in a leaf by measuring the intensity of light of a specific wavelength that is passed through a leaf. The three wavelengths of light being used corresponded to the near-IR absorption peaks of chlorophyll a, chlorophyll b, and chlorophyll-free structures. Experimentation showed that the sensor is indeed measuring levels of chlorophyll a and b and their changes before the human eye can see any changes. The detector clamp causes little damage to the leaf and will give fairly accurate readings on similar locations on a leaf, freeing the clamp from having to remain on the same spot of a leaf for all measurements. External light affects the readings only slightly so that measurements may be taken in light or dark environments. Future designs and experimentation will concentrate on reducing the size of the sensor and adapting it to a wider range of plants.
Thompson, Patricia A.; Welsh, Stuart A.; Strager, Michael P.; Rizzo, Austin A.
2018-01-01
The western sand darter Ammocrypta clara, and eastern sand darter Ammocrypta pellucida, are sand-dwelling fishes of conservation concern. Past research has emphasized the importance of studying individual populations of conservation concern, while recent research has revealed the importance of incorporating landscape scale processes that structure habitat mosaics and local populations. We examined habitat use and distributions of western and eastern sand darters in the lower Elk River of West Virginia. At the sandbar habitat use scale, western sand darters were detected in sandbars with greater area, higher proportions of coarse grain sand and faster bottom current velocity, while the eastern sand darter used a wider range of sandbar habitats. The landscape scale analysis revealed that contributing drainage area was an important predictor for both species, while sinuosity, which presumably represents valley type, also contributed to the western sand darter’s habitat suitability. Sandbar quality (area, grain size, and velocity) and fluvial geomorphic variables (drainage area and valley type) are likely key driving factors structuring sand darter distributions in the Elk River. This multiscale study of within-river species distribution and habitat use is unique, given that only a few sympatric populations are known of western and eastern sand darters.
Bitter and sweet tasting molecules: It's complicated.
Di Pizio, Antonella; Ben Shoshan-Galeczki, Yaron; Hayes, John E; Niv, Masha Y
2018-04-19
"Bitter" and "sweet" are frequently framed in opposition, both functionally and metaphorically, in regard to affective responses, emotion, and nutrition. This oppositional relationship is complicated by the fact that some molecules are simultaneously bitter and sweet. In some cases, a small chemical modification, or a chirality switch, flips the taste from sweet to bitter. Molecules humans describe as bitter are recognized by a 25-member subfamily of class A G-protein coupled receptors (GPCRs) known as TAS2Rs. Molecules humans describe as sweet are recognized by a TAS1R2/TAS1R3 heterodimer of class C GPCRs. Here we characterize the chemical space of bitter and sweet molecules: the majority of bitter compounds show higher hydrophobicity compared to sweet compounds, while sweet molecules have a wider range of sizes. Importantly, recent evidence indicates that TAS1Rs and TAS2Rs are not limited to the oral cavity; moreover, some bitterants are pharmacologically promiscuous, with the hERG potassium channel, cytochrome P450 enzymes, and carbonic anhydrases as common off-targets. Further focus on polypharmacology may unravel new physiological roles for tastant molecules. Copyright © 2018 Elsevier B.V. All rights reserved.
Laboratory Headphone Studies of Human Response to Low-Amplitude Sonic Booms and Rattle Heard Indoors
NASA Technical Reports Server (NTRS)
Loubeau, Alexandra; Sullivan, Brenda M.; Klos, Jacob; Rathsam, Jonathan; Gavin, Joseph R.
2013-01-01
Human response to sonic booms heard indoors is affected by the generation of contact-induced rattle noise. The annoyance caused by sonic boom-induced rattle noise was studied in a series of psychoacoustics tests. Stimuli were divided into three categories and presented in three different studies: isolated rattles at the same calculated Perceived Level (PL), sonic booms combined with rattles with the mixed sound at a single PL, and sonic booms combined with rattles with the mixed sound at three different PL. Subjects listened to sounds over headphones and were asked to report their annoyance. Annoyance to different rattles was shown to vary significantly according to rattle object size. In addition, the combination of low-amplitude sonic booms and rattles can be more annoying than the sonic boom alone. Correlations and regression analyses for the combined sonic boom and rattle sounds identified the Moore and Glasberg Stationary Loudness (MGSL) metric as a primary predictor of annoyance for the tested sounds. Multiple linear regression models were developed to describe annoyance to the tested sounds, and simplifications for applicability to a wider range of sounds are presented.
Very large virtual compound spaces: construction, storage and utility in drug discovery.
Peng, Zhengwei
2013-09-01
Recent activities in the construction, storage and exploration of very large virtual compound spaces are reviewed by this report. As expected, the systematic exploration of compound spaces at the highest resolution (individual atoms and bonds) is intrinsically intractable. By contrast, by staying within a finite number of reactions and a finite number of reactants or fragments, several virtual compound spaces have been constructed in a combinatorial fashion with sizes ranging from 10(11)11 to 10(20)20 compounds. Multiple search methods have been developed to perform searches (e.g. similarity, exact and substructure) into those compound spaces without the need for full enumeration. The up-front investment spent on synthetic feasibility during the construction of some of those virtual compound spaces enables a wider adoption by medicinal chemists to design and synthesize important compounds for drug discovery. Recent activities in the area of exploring virtual compound spaces via the evolutionary approach based on Genetic Algorithm also suggests a positive shift of focus from method development to workflow, integration and ease of use, all of which are required for this approach to be widely adopted by medicinal chemists.
Temperature-Dependent Conformations of Model Viscosity Index Improvers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramasamy, Uma Shantini; Cosimbescu, Lelia; Martini, Ashlie
2015-05-01
Lubricants are comprised of base oils and additives where additives are chemicals that are deliberately added to the oil to enhance properties and inhibit degradation of the base oils. Viscosity index (VI) improvers are an important class of additives that reduce the decline of fluid viscosity with temperature [1], enabling optimum lubricant performance over a wider range of operating temperatures. These additives are typically high molecular weight polymers, such as, but not limited to, polyisobutylenes, olefin copolymer, and polyalkylmethacrylates, that are added in concentrations of 2-5% (w/w). Appropriate polymers, when dissolved in base oil, expand from a coiled to anmore » uncoiled state with increasing temperature [2]. The ability of VI additives to increase their molar volume and improve the temperature-viscosity dependence of lubricants suggests there is a strong relationship between molecular structure and additive functionality [3]. In this work, we aim to quantify the changes in polymer size with temperature for four polyisobutylene (PIB) based molecular structures at the nano-scale using molecular simulation tools. As expected, the results show that the polymers adopt more conformations at higher temperatures, and there is a clear indication that the expandability of a polymer is strongly influenced by molecular structure.« less
Parreira de Castro, Diego Marcel; Reis de Carvalho, Débora; Pompeu, Paulo dos Santos; Moreira, Marcelo Zacharias; Nardoto, Gabriela Bielefeld; Callisto, Marcos
2016-01-01
It is well recognized that assemblage structure of stream macroinvertebrates changes with alterations in catchment or local land use. Our objective was to understand how the trophic ecology of benthic macroinvertebrate assemblages responds to land use changes in tropical streams. We used the isotope methodology to assess how energy flow and trophic relations among macroinvertebrates were affected in environments affected by different land uses (natural cover, pasture, sugar cane plantation). Macroinvertebrates were sampled and categorized into functional feeding groups, and available trophic resources were sampled and evaluated for the isotopic composition of 13C and 15N along streams located in the Cerrado (neotropical savanna). Streams altered by pasture or sugar cane had wider and more overlapped trophic niches, which corresponded to more generalist feeding habits. In contrast, trophic groups in streams with native vegetation had narrower trophic niches with smaller overlaps, suggesting greater specialization. Pasture sites had greater ranges of resources exploited, indicating higher trophic diversity than sites with natural cover and sugar cane plantation. We conclude that agricultural land uses appears to alter the food base and shift macroinvertebrate assemblages towards more generalist feeding behaviors and greater overlap of the trophic niches.
NASA Astrophysics Data System (ADS)
Fukuoka, Hiroshi; Watanabe, Eisuke
2017-04-01
Since Keefer published the paper on earthquake magnitude and affected area, maximum epicentral/fault distance of induced landslide distribution in 1984, showing the envelope of plots, a lot of studies on this topic have been conducted. It has been generally supposed that landslides have been triggered by shallow quakes and more landslides are likely to occur with heavy rainfalls immediately before the quake. In order to confirm this, we have collected 22 case records of earthquake-induced landslide distribution in Japan and examined the effect of hypocenter depth and antecedent precipitation. Earthquake magnitude by JMA (Japan Meteorological Agency) of the cases are from 4.5 to 9.0. Analysis on hycpocenter depth showed the deeper quake cause wider distribution. Antecedent precipitation was evaluated using the Soil Water Index (SWI), which was developed by JMA for issuing landslide alert. We could not find meaningful correlation between SWI and the earthquake-induced landslide distribution. Additionally, we found that smaller minimum size of collected landslides results in wider distribution especially between 1,000 to 100,000 m2.
The changing brain: Neuroscience and the enduring import of everyday experience
Martin, Paul; Cunningham-Burley, Sarah
2015-01-01
Discourses of ‘neuroplasticity’ have become increasingly apparent in the neurosciences and wider society. These connect with broader narratives about the ‘changing brain’ throughout the life-course. Here, we explore their presence in the talk of a range of publics. Their presence is indicative of how novel neuroscience is accepted, or not, by our participants. In particular, we suggest that any acceptance of the science relates to their personal and/or professional experiences of change (to their own or others’ subjectivities) rather than to some intrinsic and widely-held significance of scientific concepts per se. Accordingly, we also submit that it is in part through the congruence of some neuroscientific claims to everyday experiences and perspectives that the former are rendered legible and salient. In this respect, ‘lay’ knowledge has considerable import for the wider cultural authorisation of that of ‘experts’. PMID:24598481
Use of Monte Carlo simulation for the interpretation and analysis of diffuse scattering
NASA Astrophysics Data System (ADS)
Welberry, T. R.; Chan, E. J.; Goossens, D. J.; Heerdegen, A. P.
2010-02-01
With the development of computer simulation methods there is, for the first time, the possibility of having a single general method that can be used for any diffuse scattering problem in any type of system. As computers get ever faster it is expected that current methods will become increasingly powerful and applicable to a wider and wider range of problems and materials and provide results in increasingly fine detail. In this article we discuss two contrasting recent examples. The first is concerned with the two polymorphic forms of the pharmaceutical compound benzocaine. The strong and highly structured diffuse scattering in these is shown to be symptomatic of the presence of highly correlated molecular motions. The second concerns Ag+ fast ion conduction in the pearceite/polybasite family of mineral solid electrolytes. Here Monte-Carlo simulation is used to model the diffuse scattering and gain insight into how the ionic conduction arises.
NASA Astrophysics Data System (ADS)
Soto-Crespo, J. M.; Akhmediev, Nail
2002-12-01
The complex quintic Swift-Hohenberg equation (CSHE) is a model for describing pulse generation in mode-locked lasers with fast saturable absorbers and a complicated spectral response. Using numerical simulations, we study the single- and two-soliton solutions of the (1+1)-dimensional complex quintic Swift-Hohenberg equations. We have found that several types of stationary and moving composite solitons of this equation are generally stable and have a wider range of existence than for those of the complex quintic Ginzburg-Landau equation. We have also found that the CSHE has a wider variety of localized solutions. In particular, there are three types of stable soliton pairs with π and π/2 phase difference and three different fixed separations between the pulses. Different types of soliton pairs can be generated by changing the parameter corresponding to the nonlinear gain (ɛ).
Andrews, Jonathan
2012-03-01
This article examines the management and meaning of post-mortem examinations, and the spatial ordering of patients' death, dissection and burial at the Victorian asylum, referencing a range of institutional contexts and exploiting a case study of the Royal Edinburgh Asylum. The routinizing of dissection and the development of the dead-house from a more marginal asylum sector to a lynchpin of laboratory medicine is stressed. External and internal pressure to modernize pathological research facilities is assessed alongside governmental, public and professional critiques of variable necroscopy practices. This is contextualized against wider issues and attitudes surrounding consent and funereal rituals. Onus is placed on tendencies in anatomizing insanity towards the conversion of deceased lunatics--pauper lunatics especially--into mere pathological specimens. On the other hand, significant but compromised resistance on the part of a minority of practitioners, relatives and the wider public is also identified.
Gibbs, Andrew; Dunkle, Kristin; Washington, Laura; Willan, Samantha; Shai, Nwabisa; Jewkes, Rachel
2018-01-01
Childhood traumas, in the form of physical, sexual, and emotional abuse and neglect, are globally widespread and highly prevalent, and associated with a range of subsequent poor health outcomes. This study sought to understand the relationship between physical, sexual and emotional childhood abuse and subsequent HIV-risk behaviours amongst young people (18-30) living in urban informal settlements in Durban, South Africa. Data came from self-completed questionnaires amongst 680 women and 677 men comprising the baseline of the Stepping Stones and Creating Futures intervention trial. Men and women were analysed separately. Logistic regression models assessed the relationship between six HIV-risk behaviours and four measures of trauma: the form of trauma, the severity of each trauma, the range of traumas, and overall severity of childhood trauma. Childhood traumas were incredibly prevalent in this population. All childhood traumas were associated with a range of HIV-risk behaviours. This was for the ever/never trauma, as well as the severity of each type of trauma, the range of trauma, and overall severity of childhood trauma. Despite the wider harsh contexts of urban informal settlements, childhood traumas still play a significant role in shaping subsequent HIV-risk behaviours amongst young people. Interventions to reduce childhood traumas for populations in informal settlements need to be developed. In addition, trauma focused therapies need to be considered as part of wider HIV-prevention interventions for young adults. ClinicalTrials.gov NCT03022370.
NASA Astrophysics Data System (ADS)
Chardin, Jonathan; Haehnelt, Martin G.; Bosman, Sarah E. I.; Puchwein, Ewald
2018-01-01
High signal-to-noise observations of the Ly α forest transmissivity in the z = 7.085 quasi-stellar object (QSO) ULAS J1120+0641 show seven narrow transmission spikes followed by a long 240 cMpc h-1 trough. Here, we use radiative transfer simulations of cosmic reionization previously calibrated to match a wider range of Ly α forest data to show that the occurrence of seven transmission spikes in the narrow redshift range z = 5.85-6.1 is very sensitive to the exact timing of reionization. Occurrence of the spikes requires the most underdense regions of the intergalactic medium to be already fully ionized. The rapid onset of a long trough at z = 6.12 requires a strong decrease of the photoionization rate Γ at z ≳ 6.1 in this line of sight, consistent with the end of percolation at this redshift. The narrow range of reionization histories that we previously found to be consistent with a wider range of Ly α forest data have a reasonable probability of showing seven spikes and the mock absorption spectra provide an excellent match to the spikes and the trough in the observed spectrum of ULAS J1120+0641. Larger samples of high signal-to-noise searches for rare Ly α transmission spikes at z > 5.8 should therefore provide important further insights into the exact timing of the percolation of H II bubbles at the tail end of reionization.
Dunkle, Kristin; Washington, Laura; Willan, Samantha; Shai, Nwabisa; Jewkes, Rachel
2018-01-01
Childhood traumas, in the form of physical, sexual, and emotional abuse and neglect, are globally widespread and highly prevalent, and associated with a range of subsequent poor health outcomes. This study sought to understand the relationship between physical, sexual and emotional childhood abuse and subsequent HIV-risk behaviours amongst young people (18–30) living in urban informal settlements in Durban, South Africa. Data came from self-completed questionnaires amongst 680 women and 677 men comprising the baseline of the Stepping Stones and Creating Futures intervention trial. Men and women were analysed separately. Logistic regression models assessed the relationship between six HIV-risk behaviours and four measures of trauma: the form of trauma, the severity of each trauma, the range of traumas, and overall severity of childhood trauma. Childhood traumas were incredibly prevalent in this population. All childhood traumas were associated with a range of HIV-risk behaviours. This was for the ever/never trauma, as well as the severity of each type of trauma, the range of trauma, and overall severity of childhood trauma. Despite the wider harsh contexts of urban informal settlements, childhood traumas still play a significant role in shaping subsequent HIV-risk behaviours amongst young people. Interventions to reduce childhood traumas for populations in informal settlements need to be developed. In addition, trauma focused therapies need to be considered as part of wider HIV-prevention interventions for young adults. Trial registration: ClinicalTrials.gov NCT03022370 PMID:29624612
Copper Filtration and kVp: Effect on Entrance Skin Exposure.
Barba, James; Culp, Melissa
2015-01-01
The selection of technical factors to produce an image is driven primarily by the patient, body part, and factors regarding the status of that patient or part. Analog receptor systems are restricted by the ranges of data they are able to record, as well as the quantity and quality of data required to record an image. Using digital receptors allows for a wider range of exposure factors because of the nature of the receptor systems and the data processing methods employed. Thus, factor selection can be more patient centered when using digital receptors to produce a radiograph. To explore the relationship between milliampere seconds (mAs), kilovoltage peak (kVp), and additional copper filtration with exposure indicators and entrance skin exposure (ESE) using both analog and digital receptors. Researchers conducted 2-tailed t-tests using Stata/IC version 11.2 software (StataCorp LP) to compare ESE from several trials using hip and knee phantoms. The analysis indicated that increasing kVp, adding 0.1 mm copper filtration, and correspondingly reducing mAs reduced ESE on a hip phantom by 64%, from 151 mR to 54.4 mR and reduced ESE on a knee phantom by 51%, from 27.2 mR to 13.4 mR. Radiology departments and radiologic technologists can consider these data when creating dose reduction protocols. The wider latitude range of digital radiography can be used to minimize patient exposure while still producing images of diagnostic quality within the acceptable exposure indicator range stated by the manufacturer.
Similarity of Stream Width Distributions Across Headwater Systems
NASA Astrophysics Data System (ADS)
Allen, G. H.; Pavelsky, T.; Barefoot, E. A.; Tashie, A.; Butman, D. E.
2016-12-01
The morphology and abundance of streams control the rates of hydraulic and biogeochemical exchange between streams, groundwater, and the atmosphere. In large river systems, studies have used remote sensing to quantify river morphology, and have found that the relationship between river width and abundance is fractal, such that narrow rivers are proportionally more common than wider rivers. However, in headwater systems (stream order 1-3), where many biogeochemical reactions are most rapid, the relationship between stream width and abundance is unknown, reducing the certainty of biogeochemical flux estimates. To constrain this uncertainty, we surveyed two components of stream morphology (wetted stream width and length) in seven physiographically contrasting stream networks in Kings Creek in Konza Prarie, KS; Sagehen Creek in the N. Sierra Nevada Mtns., CA; Elder Creek in Angelo Coast Range Preserve, CA; Caribou Creek in the Caribou Poker Creek Research Watershed, AK; V40 Stream, NZ; Blue Duck Creek, NZ; Stony Creek in Duke Forest, NC. To assess temporal variations, we also surveyed stream geometry in a subcatchment of Stony Creek six times over a range of moderate streamflow conditions (discharge less than 90 percentile of gauge record). Here we show a strikingly consistent gamma statistical distribution of stream width in all surveys and a characteristic most abundant stream width of 32±7 cm independent of flow conditions or basin size. This consistency is remarkable given the substantial physical diversity among the studied catchments. We propose a model that invokes network topology theory and downstream hydraulic geometry to show that, as active drainage networks expand and contract in response to changes in streamflow, the most abundant stream width remains approximately static. This framework can be used to better extrapolate stream size and abundance from large rivers to small headwater streams, with significant impact on understanding of the hydraulic, ecological, and biogeochemical functions of stream networks.
del Moral, F; Vázquez, J A; Ferrero, J J; Willisch, P; Ramírez, R D; Teijeiro, A; López Medina, A; Andrade, B; Vázquez, J; Salvador, F; Medal, D; Salgado, M; Muñoz, V
2009-09-01
Modern radiotherapy uses complex treatments that necessitate more complex quality assurance procedures. As a continuous medium, GafChromic EBT films offer suitable features for such verification. However, its sensitometric curve is not fully understood in terms of classical theoretical models. In fact, measured optical densities and those predicted by the classical models differ significantly. This difference increases systematically with wider dose ranges. Thus, achieving the accuracy required for intensity-modulated radiotherapy (IMRT) by classical methods is not possible, plecluding their use. As a result, experimental parametrizations, such as polynomial fits, are replacing phenomenological expressions in modern investigations. This article focuses on identifying new theoretical ways to describe sensitometric curves and on evaluating the quality of fit for experimental data based on four proposed models. A whole mathematical formalism starting with a geometrical version of the classical theory is used to develop new expressions for the sensitometric curves. General results from the percolation theory are also used. A flat-bed-scanner-based method was chosen for the film analysis. Different tests were performed, such as consistency of the numeric results for the proposed model and double examination using data from independent researchers. Results show that the percolation-theory-based model provides the best theoretical explanation for the sensitometric behavior of GafChromic films. The different sizes of active centers or monomer crystals of the film are the basis of this model, allowing acquisition of information about the internal structure of the films. Values for the mean size of the active centers were obtained in accordance with technical specifications. In this model, the dynamics of the interaction between the active centers of GafChromic film and radiation is also characterized by means of its interaction cross-section value. The percolation model fulfills the accuracy requirements for quality-control procedures when large ranges of doses are used and offers a physical explanation for the film response.
NASA Astrophysics Data System (ADS)
Deardorff, N.; Cashman, K. V.; Chadwick, W. W.; Embley, R. W.
2007-12-01
Strombolian submarine eruptions at 550-560 m water depth were observed in April, 2006 at NW Rota-1 volcano, Mariana arc. During six dives with the Jason II remotely operated vehicle observations made at close range documented a diverse and increasingly energetic range of activity. The initial dives observed lava extrusion followed by small, explosive bursts. Activity steadily increased to produce gas thrust jets, discrete thermals and eventually a sustained plume. Eruption video allowed analysis of submarine plume dynamics and depositional characteristics. Sustained plumes were white, billowy and coherent, measuring ~0.5-0.75m wide at their base and quickly spreading to >2m in diameter within ~2-3m above vent due to rapid seawater entrainment. Sustained, coherent plumes were observed rising >20-30m above the seafloor; the top of the plume was observed at ~490m b.s.l giving a total plume height of ~60-70m above the active vent. The initial ascent (<3-4 m) of plumes generated from explosive bursts was analyzed for ejection velocities (<4m/s), clast settling velocities (~0.38-0.72m/s), and changes in plume height and width. Gas thrust jets were determined to transition from momentum-driven plume rise to buoyancy-driven plumes, both visually and using rise velocities, at ~ 0.5-1 m above the vent. These data contrast with the dynamics of plumes generated in subaerial Strombolian eruptions, which maintain momentum-driven rise to ~ 100 meters (Patrick, 2007) above the vent, and illustrate the strong dampening effect of the overlying seawater. Ash and lapilli were observed falling out of the plume at heights >3-4m after being transported by the convecting plume and are assumed to have wider range of travel, vertically and laterally, and deposition. Most bomb-sized ejecta were carried vertically with the plume for 1-3m before falling out around the vent, indicating that the dense (~1700-2350 kg/m3) clasts were transported primarily within the momentum-driven part of the plume. These bomb-sized ejecta were deposited within ~1-2m from the vent with numerous clasts falling back into the vent. The average maximum bomb size increased over time from <13cm blocks during early phases of the dive sequence to ~30-70cm during the later, most energetic eruptions. The positive correlation of bomb size with mass eruption rate is opposite to that seen for highly explosive (plinian) eruptions and suggests that mass eruption rate at NW Rota-1 is determined primarily by gas flux (that is, the ability of the streaming gas phase to transport pyroclasts).
The Critical Size Defect as an Experimental Model for Craniomaxillofacial Nonunions,
1985-01-01
union evident at two months. The wider defects of 12 m, 15 m, and 18 mm in length exhibited bony union in four months but exhibited drainage either...Prolo, D.J., (-btierrez, R.V., DeVine, J.S., and (*und, R.A.: Clinical l1tility of Alloqeneic Skull Discs in Human Craniotomy . Neurosurgery. 14:1R3, 1984...1. R rm craniotomy defect prepared in dried rat skull. Piq. 2. 15 rm craniotamy defect in dried rabbit skull. Fig. 3. r-ied dog mandible qhowing
Improving color characteristics of LCD
NASA Astrophysics Data System (ADS)
Feng, Xiao-fan; Daly, Scott J.
2005-01-01
The drive for larger size, higher spatial resolution, and wider aperture LCD has shown to increase the electrical crosstalk between electrodes in the driver circuit. This crosstalk leads to additivity errors in color LCD. In this paper, the crosstalk effect was analyzed with micrographs captured from an imaging colorimeter. The experimental result reveals the subpixel nature of color crosstalk. A spatial-based subpixel crosstalk correction algorithm was developed to improve the color performance of LCD. Compared to a 3D lookup table approach, the new algorithm is easier to implement and more accurate in performance.
Seed predators exert selection on the subindividual variation of seed size.
Sobral, M; Guitián, J; Guitián, P; Larrinaga, A R
2014-07-01
Subindividual variation among repeated organs in plants constitutes an overlooked level of variation in phenotypic selection studies, despite being a major component of phenotypic variation. Animals that interact with plants could be selective agents on subindividual variation. This study examines selective pressures exerted during post-dispersal seed predation and germination on the subindividual variation of seed size in hawthorn (Crataegus monogyna). With a seed offering experiment and a germination test, we estimated phenotypic selection differentials for average and subindividual variation of seed size due to seed predation and germination. Seed size affects germination, growth rate and the probability of an individual seed of escaping predation. Longer seeds showed higher germination rates, but this did not result in significant selection on phenotypes of the maternal trees. On the other hand, seed predators avoided wider seeds, and by doing so exerted phenotypic selection on adult average and subindividual variation of seed size. The detected selection on subindividual variation suggests that the levels of phenotypic variation within individual plants may be, at least partly, the adaptive consequence of animal-mediated selection. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.
Performance of an Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy
NASA Technical Reports Server (NTRS)
Newman, Kevin; Belikov, Ruslan; Pluzhnik, Eugene; Balasubramanian, Kunjithapatham; Wilson, Dan
2014-01-01
Coronagraph technology combined with wavefront control is close to achieving the contrast and inner working angle requirements in the lab necessary to observe the faint signal of an Earth-like exoplanet in monochromatic light. An important remaining technological challenge is to achieve high contrast in broadband light. Coronagraph bandwidth is largely limited by chromaticity of the focal plane mask, which is responsible for blocking the stellar PSF. The size of a stellar PSF scales linearly with wavelength; ideally, the size of the focal plane mask would also scale with wavelength. A conventional hard-edge focal plane mask has a fixed size, normally sized for the longest wavelength in the observational band to avoid starlight leakage. The conventional mask is oversized for shorter wavelengths and blocks useful discovery space. Recently we presented a solution to the size chromaticity challenge with a focal plane mask designed to scale its effective size with wavelength. In this paper, we analyze performance of the achromatic size-scaling focal plane mask within a Phase Induced Amplitude Apodization (PIAA) coronagraph. We present results from wavefront control around the achromatic focal plane mask, and demonstrate the size-scaling effect of the mask with wavelength. The edge of the dark zone, and therefore the inner working angle of the coronagraph, scale with wavelength. The achromatic mask enables operation in a wider band of wavelengths compared with a conventional hard-edge occulter.
Fish movement and habitat use depends on water body size and shape
Woolnough, D.A.; Downing, J.A.; Newton, T.J.
2009-01-01
Home ranges are central to understanding habitat diversity, effects of fragmentation and conservation. The distance that an organism moves yields information on life history, genetics and interactions with other organisms. Present theory suggests that home range is set by body size of individuals. Here, we analyse estimates of home ranges in lakes and rivers to show that body size of fish and water body size and shape influence home range size. Using 71 studies including 66 fish species on five continents, we show that home range estimates increased with increasing water body size across water body shapes. This contrasts with past studies concluding that body size sets home range. We show that water body size was a consistently significant predictor of home range. In conjunction, body size and water body size can provide improved estimates of home range than just body size alone. As habitat patches are decreasing in size worldwide, our findings have implications for ecology, conservation and genetics of populations in fragmented ecosystems. ?? 2008 Blackwell Munksgaard.
Dose ratio proton radiography using the proximal side of the Bragg peak
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doolan, P. J., E-mail: paul.doolan.09@ucl.ac.uk; Royle, G.; Gibson, A.
Purpose: In recent years, there has been a movement toward single-detector proton radiography, due to its potential ease of implementation within the clinical environment. One such single-detector technique is the dose ratio method in which the dose maps from two pristine Bragg peaks are recorded beyond the patient. To date, this has only been investigated on the distal side of the lower energy Bragg peak, due to the sharp falloff. The authors investigate the limits and applicability of the dose ratio method on the proximal side of the lower energy Bragg peak, which has the potential to allow a muchmore » wider range of water-equivalent thicknesses (WET) to be imaged. Comparisons are made with the use of the distal side of the Bragg peak. Methods: Using the analytical approximation for the Bragg peak, the authors generated theoretical dose ratio curves for a range of energy pairs, and then determined how an uncertainty in the dose ratio would translate to a spread in the WET estimate. By defining this spread as the accuracy one could achieve in the WET estimate, the authors were able to generate lookup graphs of the range on the proximal side of the Bragg peak that one could reliably use. These were dependent on the energy pair, noise level in the dose ratio image and the required accuracy in the WET. Using these lookup graphs, the authors investigated the applicability of the technique for a range of patient treatment sites. The authors validated the theoretical approach with experimental measurements using a complementary metal oxide semiconductor active pixel sensor (CMOS APS), by imaging a small sapphire sphere in a high energy proton beam. Results: Provided the noise level in the dose ratio image was 1% or less, a larger spread of WETs could be imaged using the proximal side of the Bragg peak (max 5.31 cm) compared to the distal side (max 2.42 cm). In simulation, it was found that, for a pediatric brain, it is possible to use the technique to image a region with a square field equivalent size of 7.6 cm{sup 2}, for a required accuracy in the WET of 3 mm and a 1% noise level in the dose ratio image. The technique showed limited applicability for other patient sites. The CMOS APS demonstrated a good accuracy, with a root-mean-square-error of 1.6 mm WET. The noise in the measured images was found to be σ = 1.2% (standard deviation) and theoretical predictions with a 1.96σ noise level showed good agreement with the measured errors. Conclusions: After validating the theoretical approach with measurements, the authors have shown that the use of the proximal side of the Bragg peak when performing dose ratio imaging is feasible, and allows for a wider dynamic range than when using the distal side. The dynamic range available increases as the demand on the accuracy of the WET decreases. The technique can only be applied to clinical sites with small maximum WETs such as for pediatric brains.« less
Watson, Derrick G
2017-01-01
I propose that there remains a central role for the item (or its equivalent) in a wider range of search and search-related tasks/functions than might be conveyed by the article. I consider the functional relationship between the framework and some aspects of previous theories, and suggest some challenges that the new framework might encounter.
The Building 549 auditorium is often packed with high school interns eager to hear a scientific lecture. On April 22, however, the room swelled with interns spanning a wider age range. At the 25th Werner H. Kirsten Student Intern Program (WHK SIP) Anniversary Symposium, incoming, current, and former interns gathered to celebrate the program, which has provided biomedical
Weathering of iron sulfides under Mars surface ambient conditions
NASA Technical Reports Server (NTRS)
Blackburn, T. R.
1981-01-01
The study of iron sulfide surface alternation reactions under Mars' surface ambient conditions begun during 1980 was extended through improved irradiation design and experimental protocols. A wider range of humidities and more intense irradiation were incorporated in the study. X-ray photoelectron spectra of irradiated chips suggest formation of FeSO4, FeCO3, and an iron oxide on the iron sulfide substrates studied.
Flexistudy: A Development at Barnet College. Coombe Lodge Case Study. Information Bank Number 1351.
ERIC Educational Resources Information Center
Albrecht, A.; Spencer, D. C.
An outline is presented of Barnet College's flexistudy program, a system for providing a wider range of learning opportunities through a more flexible arrangement of course times and content to students who are unable to attend college regularly, who are too few in number to form a specialist class, or who wish to start school at some time other…
John Podgwaite; Viatcheslav Martemyanov; Stanislav Bakhvalov
2007-01-01
Periodic intrusions of Asian strains of gypsy moth, Lymantria dispar L., into North America have occurred over the past several years. Preventative measures in the countries of origin and around ports of entry in North America have lowered the risk of invasion and establishment but the threat remains current. Asian strains have a wider host range...
Medtech: Potential for innovation.
Bestetti, Gilberto
2009-10-17
Switzerland, with its ETHZ and EPFL, universities, advanced technical colleges, the CSEM, the Empa and the Paul Scherrer Institute, possesses a complete chain of knowledge and interdisciplinary competence which ranks it among the worldwide leaders in medical technology. To ensure that a wider range of excellent research results are translated into marketable products and methods, the CTI Agency for the Promotion of Innovation launched the Medtech initiative, a success story.
Multinational Experiment 7. Regional Analysis: Wider Mediterranean
2013-07-08
crossroads for the maritime trade and the global economic flows, the Mediterranean Sea is something like a lab where maritime security initiatives could...and their economic development. One of the most critical areas in the world partially faces the Mediterranean: the Middle East. As stated, 21...Nations have a coastline on the Mediterranean Sea, offering a wide range of economical , political, cultural and religious perspectives that hamper the
The 2015 National Security Strategy: Authorities, Changes, Issues for Congress
2016-02-26
climate change ; ensure access to shared spaces (expanding cyberspace and including outer space and air and maritime security); and increase global...hand, one could conclude that these, along with confronting climate change , convey both a wider range of national security challenges in terms of...The 2015 National Security Strategy: Authorities, Changes , Issues for Congress Nathan J. Lucas, Coordinator Section Research Manager Kathleen
Range Estimation Algorithm Comparison in 3-D Flash LADAR Data
2009-03-01
formed from LADAR intensity data viewed at sample 10. Target is about 70 meters from receiver and normal to line of sight. White square indicates region...that when averaged form a pulse that is slightly wider than the individual returns. . . . . . . . 35 4.1 Examples of simulated LADAR waveforms of...varying widths used for PWE tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 4.2 Simulated noiseless data buffered through LADAR sytem
Phosphorus translocation by red deer on a subalpine grassland in the central European Alps
Martin Schutz; Anita C. Risch; Gerald Achermann; Conny Thiel-Egenter; Deborah Page-Dumroese; Martin F. Jurgensen; Peter J. Edward
2006-01-01
We examined the role of red deer (Cervus elaphus L.) in translocating phosphorus (P) from their preferred grazing sites (short-grass vegetation on subalpine grasslands) to their wider home range in a subalpine grassland ecosystem in the Central European Alps. Phosphorus was used because it is the limiting nutrient in these grasslands. When we compared P removal of...
Universal Declaration of Human Rights, A Lay Version for the Common Man, Woman and Child.
ERIC Educational Resources Information Center
Tankard, Alice Doumanian
This lay version of the Universal Declaration of Human Rights (the original version was adopted by the General Assembly of the United Nations in 1948) has been written in simplified vocabulary to make it understandable to a wider range of ages and reading abilities. The declaration consists of a preamble followed by a listing of 30 goals common to…
Plantation Spacing Affects Early Growth of Planted Virginia Pine
T.E. Russell
1979-01-01
Spacings ranging from 4 x 4 to 8 x 8 ft did not affect 15 year height growth of Virginia pines planted on a cutover Cumberland Plateau site. Wider spacings produced trees of larger diameters than did closer spacings; closer spacings had more basal area and volume. Although height to the base of the live crown increased as spacing narrowed, self-pruning was poor at all...
ERIC Educational Resources Information Center
Boatman, Angela; Long, Bridget Terry
2018-01-01
We examine the impact of remedial and developmental courses on college students with varying levels of academic preparedness, thus focusing on a wider range of students than previous studies. Using a regression discontinuity design, we provide causal estimates of the effects of placement in different levels of remedial courses on short-,…
Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pluth, Michael D.; Raymond, Kenneth N.; Bergman, Robert G.
2008-02-16
Inspired by the efficiency and selectivity of enzymes, synthetic chemists have designed and prepared a wide range of host molecules that can bind smaller molecules with their cavities; this area has become known as 'supramolecular' or 'host-guest' chemistry. Pioneered by Lehn, Cram, Pedersen, and Breslow, and followed up by a large number of more recent investigators, it has been found that the chemical environment in each assembly - defined by the size, shape, charge, and functional group availability - greatly influences the guest-binding characteristics of these compounds. In contrast to the large number of binding studies that have been carriedmore » out in this area, the exploration of chemistry - especially catalytic chemistry - that can take place inside supramolecular host cavities is still in its infancy. For example, until the work described here was carried out, very few examples of organometallic reactivity inside supramolecular hosts were known, especially in water solution. For that reason, our group and the group directed by Kenneth Raymond decided to take advantage of our complementary expertise and attempt to carry out metal-mediated C-H bond activation reactions in water-soluble supramolecular systems. This article begins by providing background from the Raymond group in supramolecular coordination chemistry and the Bergman group in C-H bond activation. It goes on to report the results of our combined efforts in supramolecular C-H activation reactions, followed by extensions of this work into a wider range of intracavity transformations.« less
Ovadnevaite, J; Kvietkus, K; Sakalys, J
2007-09-01
Ambient particles vary greatly in their ability to affect visibility, climate and human health. The fine fraction of aerosol is responsible for greater and wider effects on human health; thus, investigation of this fraction is very important. Continuous measurements of PM2.5 (particulate matter below 2.5 microm in size) concentrations at the Preila monitoring station started in 2003. During a period of 2 years, the episodes of high daily and semi-hourly concentrations of PM2.5 were measured. These episodes did not depend on the season or time of day. The substantial role of long-range transport of pollutants to these increases in concentration was shown using chemical and statistical analysis. It was found that most of the severe episodes occurred when air masses came from a specific site besides it was established that air masses of different origin were characterized by different mixing layer depth. Lower mixing depth was observed in air masses characterized by higher observed concentrations at the measuring site and vice versa. PM2.5 concentrations showed diurnal and seasonal variations whose pattern reflected the regional origin of the aerosol. The regional pollution level was evaluated by the statistical analysis of PM2.5 concentrations. The background annual average of PM2.5 mass concentration for the eastern coast of the Baltic Sea was 15.1 +/- 0.8 microg m(-3).
Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
NASA Technical Reports Server (NTRS)
Kopparapu, Ravi Kumar; Ramirez, Ramses M.; Kotte, James Schottel; Kasting, James F.; Domagal-Goldman, Shawn; Eymet, Vincent
2014-01-01
The ongoing discoveries of extra-solar planets are unveiling a wide range of terrestrial mass (size) planets around their host stars. In this Letter, we present estimates of habitable zones (HZs) around stars with stellar effective temperatures in the range 2600 K-7200 K, for planetary masses between 0.1M and 5M. Assuming H2O-(inner HZ) and CO2-(outer HZ) dominated atmospheres, and scaling the background N2 atmospheric pressure with the radius of the planet, our results indicate that larger planets have wider HZs than do smaller ones. Specifically, with the assumption that smaller planets will have less dense atmospheres, the inner edge of the HZ (runaway greenhouse limit) moves outward (approx.10% lower than Earth flux) for low mass planets due to larger greenhouse effect arising from the increased H2O column depth. For larger planets, the H2O column depth is smaller, and higher temperatures are needed before water vapor completely dominates the outgoing long-wave radiation. Hence the inner edge moves inward (approx.7% higher than Earth's flux). The outer HZ changes little due to the competing effects of the greenhouse effect and an increase in albedo. New, three-dimensional climate model results from other groups are also summarized, and we argue that further, independent studies are needed to verify their predictions. Combined with our previous work, the results presented here provide refined estimates of HZs around main-sequence stars and provide a step toward a more comprehensive analysis of HZs.
Improved Apparatus for Testing Monoball Bearings
NASA Technical Reports Server (NTRS)
Hall, Phillip B.; Novak, Howard L.
2006-01-01
A desk-sized apparatus for testing monoball bearings and their lubricants offers advantages, relative to prior such apparatuses, of (1) a greater degree of automation and (2) capability of operation under wider and more realistic ranges of test conditions. The ranges of attainable test conditions include load from 100 to greater h than 50,000 lb (445 to greater than 2.22 x 10(exp 5) N), resisting torque up to 30,000 lb-in. (approximately equal to 3,390 N-m), oscillating rotation through an angle as large as 280 degrees, and oscillation frequency from 0 to 6 Hz. With addition of some components and without major modification of the apparatus, it is also possible to perform tests under environmental conditions that include temperature from -320 to 1,000 F (-196 to +538 C), relative humidity from 0 to 100 percent, and either air at ambient pressure, high vacuum, or an atmosphere of monatomic oxygen. In the apparatus (see Figure 1), a monoball bearing specimen is driven in oscillating rotation by a hydraulic rotary actuator through a series of shafts, one of which incorporates a torque meter and one of which is a flexible coupling. The torque meter measures the resisting torque; the flexible coupling accommodates misalignment, wear, and compression of the specimen and ensures equal loading on opposite sides of the monoball. Not shown in the figure is an angular-position sensor that is used for measuring the angle of rotation of the shafts.
Cellular Convection in a Chamber with a Warm Surface Raft
NASA Astrophysics Data System (ADS)
Whitehead, John; Shea, Erin; Behn, Mark
2011-11-01
We calculate velocity and temperature fields for Rayleigh-Benard convection in a chamber with a warm raft that can float along the top surface for Rayleigh number up to Ra=20,000. Two-dimensional, infinite Prandtl number, Boussinesq approximation equations are numerically advanced in time from a motionless state in a chamber of length L' and depth D'. We consider cases with an insulated raft and a raft of fixed temperature. Either oscillatory or stationary flow exists. The case of an insulated raft has three governing parameters: Ra, scaled chamber length L=L'/D', and scaled raft width W. For W=0 and L=1, the marginal state is at Ra=779.3. For smallest W (determined by numerical grid size) and Ra <790 the raft approaches the center monotonically in time. For 790
NASA Astrophysics Data System (ADS)
Cho, T.; Sakamoto, Y.; Hirata, M.; Kohagura, J.; Makino, K.; Kanke, S.; Takahashi, K.; Okamura, T.; Nakashima, Y.; Yatsu, K.; Tamano, T.; Miyoshi, S.
1997-01-01
For the purpose of plasma-ion-energy analyses in a wide-energy range from a few hundred eV to hundreds of keV, upgraded semiconductor detectors are newly fabricated and characterized using a test-ion-beam line from 0.3 to 12 keV. In particular, the detectable lowest-ion energy is drastically improved at least down to 0.3 keV; this energy is one to two orders-of-magnitude better than those for commercially available Si-surface-barrier diodes employed for previous plasma-ion diagnostics. A signal-to-noise ratio of two to three orders-of-magnitude better than that for usual metal-collector detectors is demonstrated for the compact-sized semiconductor along with the availability of the use under conditions of a good vacuum and a strong-magnetic field. Such characteristics are achieved due to the improving methods of the optimization of the thicknesses of a Si dead layer and a SiO2 layer, as well as the nitrogen-doping technique near the depletion layer along with minimizing impurity concentrations in Si. Such an upgraded capability of an extremely low-energy-ion detection with the low-noise characteristics enlarges research regimes of plasma-ion behavior using semiconductor detectors not only in the divertor regions of tokamaks but in wider spectra of open-field plasma devices including tandem mirrors. An application of the semiconductor ion detector for plasma-ion diagnostics is demonstrated in a specially designed ion-spectrometer structure.
Beckmann, Manfred; Enot, David P; Overy, David P; Scott, Ian M; Jones, Paul G; Allaway, David; Draper, John
2010-04-01
Selective breeding of dogs has culminated in a large number of modern breeds distinctive in terms of size, shape and behaviour. Inadvertently, a range of breed-specific genetic disorders have become fixed in some pure-bred populations. Several inherited conditions confer chronic metabolic defects that are influenced strongly by diet, but it is likely that many less obvious breed-specific differences in physiology exist. Using Labrador retrievers and miniature Schnauzers maintained in a simulated domestic setting on a controlled diet, an experimental design was validated in relation to husbandry, sampling and sample processing for metabolomics. Metabolite fingerprints were generated from 'spot' urine samples using flow injection electrospray MS (FIE-MS). With class based on breed, urine chemical fingerprints were modelled using Random Forest (a supervised data classification technique), and metabolite features (m/z) explanatory of breed-specific differences were putatively annotated using the ARMeC database (http://www.armec.org). GC-MS profiling to confirm FIE-MS predictions indicated major breed-specific differences centred on the metabolism of diet-related polyphenols. Metabolism of further diet components, including potentially prebiotic oligosaccharides, animal-derived fats and glycerol, appeared significantly different between the two breeds. Analysis of the urinary metabolome of young male dogs representative of a wider range of breeds from animals maintained under domestic conditions on unknown diets provided preliminary evidence that many breeds may indeed have distinctive metabolic differences, with significant differences particularly apparent in comparisons between large and smaller breeds.
NASA Astrophysics Data System (ADS)
Li, Xin; Liang, Ji; Zhang, Hongxiang; Yang, Xing; Zhang, Hao; Pang, Wei; Zhang, Menglun
2017-06-01
This paper reports an uncooled infrared (IR) detector based on a micromachined piezoelectric resonator operating in resonant and resistive dual-modes. The two sensing modes achieved IR responsivities of 2.5 Hz/nW and 900 μdB/nW, respectively. Compared with the single mode operation, the dual-mode measurement improves the limit of detection by two orders of magnitude and meanwhile maintains high linearity and responsivity in a higher IR intensity range. A combination of the two sensing modes compensates for its own shortcomings and provides a much larger dynamic range, and thus, a wider application field of the proposed detector is realized.
ERIC Educational Resources Information Center
Meyer, Mary C.
2006-01-01
From a very young age, shoes for boys tend to be wider than shoes for girls. Is this because boys have wider feet, or because it is assumed that girls are willing to sacrifice comfort for fashion, even in elementary school? To assess the former, a statistician measures kids' feet. (Contains 2 tables and 3 figures.)
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.
Design variability in web geometry of an orb-weaving spider.
Vollrath, F; Downes, M; Krackow, S
1997-10-01
We studied the effect of several variables (environmental and physiological) on web geometry in the garden cross spider Araneus diadematus. Variables were: web support, wind, temperature, humidity, and silk supply. All had an effect. The spiders generally attempted to fit their webs to the shape of the supporting frame (standard, small, vertical, or horizontal). Windy conditions (0.5 m s-1) during web construction caused spiders to build smaller and rounder webs, laying down fewer capture spirals while increasing the distances between capture-spiral meshes. Decreasing temperature from 24 degrees to 12 degrees C caused the capture spiral to have fewer and wider spaced meshes, which did not change overall capture area but reduced the length of capture-spiral threads laid down. Subsequent increase of temperature to 24 degrees C restored the number of meshes laid down, but the wider mesh was retained, causing the capture area to be increased over initial control values. Decreased humidity (from 70 to 20% rH) had the effect of reducing web and capture-spiral size, the latter by reducing mesh number while keeping mesh spacing constant. Subsequent increase of humidity to control level (70%) restored web and capture area. However, this was achieved by laying down capture meshes at larger distances, rather than returning to initial mesh numbers. Silk supply also had a strong effect. Webs built in unnaturally rapid succession by the same spider (4 in 24 h when 1 is the norm) became sequentially smaller, had fewer radii, shorter capture spirals, and were wider meshed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaminski, Adam
A method and apparatus to generate harmonically related laser wavelengths includes a pair of lenses at opposing faces of a non-linear optical material. The lenses are configured to promote incoming and outgoing beams to be normal to each outer lens surface over a range of acceptance angles of the incoming laser beam. This reduces reflection loss for higher efficiency operation. Additionally, the lenses allow a wider range of wavelengths for lasers for more universal application. Examples of the lenses include plano-cylindrical and plano-spherical form factors.
Towards a Standardized Line List for G 191-B2B and other DA Type Objects
NASA Astrophysics Data System (ADS)
Preval, S. P.; Barstow, M. A.; Holberg, J. B.; Dickinson, N. J.
2013-01-01
We present a comprehensive analysis of the far UV spectrum of G 191-B2B over the range of 900-1700Å using co-added data from the FUSE and STIS archives. While previous identifications made by Holberg et al. (2003) are reaffirmed in this work, it is found that many previously unidentified lines can now be attributed to Fe, Ni, and a few lighter metals. Future work includes extending this detailed analysis to a wider range of DA objects, in the expectation that a more complete analysis of their atmospheres can be realised.
Practical problems which women encounter with available contraception in Australia.
Weisberg, E
1994-06-01
Australian women face major difficulties with contraception because of the limited range of choices, the need for meticulous attention to compliance with most available methods and because of cost limitations for a significant minority of the population. The most commonly used methods are oral contraceptive pills and barrier methods, and each has substantial compliance problems which can be minimized with care and counselling. There is an urgent need for a wider range of options in Australia and for good information and publicity about them. Present progress in this direction gives some hope for the near future.
NASA Astrophysics Data System (ADS)
Bodryakov, V. Yu.; Bykov, A. A.
2016-05-01
The correlation between the volumetric thermal expansion coefficient β( T) and the heat capacity C( T) of aluminum is considered in detail. It is shown that a clear correlation is observed in a significantly wider temperature range, up to the melting temperature of the metal, along with the low-temperature range where it is linear. The significant deviation of dependence β( C) from the low-temperature linear behavior is observed up to the point where the heat capacity achieves the classical Dulong-Petit limit of 3 R ( R is the universal gas constant).
Wealth generation through recycling of material for reuse
NASA Astrophysics Data System (ADS)
Chukwudum, Okechukw John; Patience I., E.
2018-06-01
Management of solid waste needs appropriate technology, which is economically affordable, socially accepted and environmentally friendly. The public needs to be sensitized on the potential wealth that their inorganic and organic wastes contain. The paper deals with the idea of recycling as a means of solid waste treatment and explores. In developing countries, where standards are often lower and raw materials very expensive, there is a wider scope for use of recycled material. The range of products varies from building materials to shoes, home to office equipment, sewage pipe to beauty aids. Recyclingand reuse issues overlap a range of disciplines.
Operation of a New COTS Crystal Oscillator - CXOMHT over a Wide Temperature Range
NASA Technical Reports Server (NTRS)
Patterson, Richard; Hammoud, Ahmad
2011-01-01
Crystal oscillators are extensively used in electronic circuits to provide timing or clocking signals in data acquisition, communications links, and control systems, to name a few. They are affordable, small in size, and reliable. Because of the inherent characteristics of the crystal, the oscillator usually exhibits extreme accuracy in its output frequency within the intrinsic crystal stability. Stability of the frequency could be affected under varying load levels or other operational conditions. Temperature is one of those important factors that influence the frequency stability of an oscillator; as it does to the functionality of other electronic components. Electronics designed for use in NASA deep space and planetary exploration missions are expected to be exposed to extreme temperatures and thermal cycling over a wide range. Thus, it is important to design and develop circuits that are able to operate efficiently and reliably under in these harsh temperature environments. Most of the commercial-off-the-shelf (COTS) devices are very limited in terms of their specified operational temperature while very few custom-made commercial and military-grade parts have the ability to operate in a slightly wider range of temperature than those of the COTS parts. These parts are usually designed for operation under one temperature extreme, i.e. hot or cold, and do not address the wide swing in the operational temperature, which is typical of the space environment. For safe and successful space missions, electronic systems must therefore be designed not only to withstand the extreme temperature exposure but also to operate efficiently and reliably. This report presents the results obtained on the evaluation of a new COTS crystal oscillator under extreme temperatures.
Burrows, Anne M; Waller, Bridget M; Micheletta, Jérôme
2016-10-01
Facial displays (or expressions) are a primary means of visual communication among conspecifics in many mammalian orders. Macaques are an ideal model among primates for investigating the co-evolution of facial musculature, facial displays, and social group size/behavior under the umbrella of "ecomorphology". While all macaque species share some social behaviors, dietary, and ecological parameters, they display a range of social dominance styles from despotic to tolerant. A previous study found a larger repertoire of facial displays in tolerant macaque species relative to despotic species. The present study was designed to further explore this finding by comparing the gross morphological features of mimetic muscles between the Sulawesi macaque (Macaca nigra), a tolerant species, and the rhesus macaque (M. mulatta), a despotic species. Five adult M. nigra heads were dissected and mimetic musculature was compared to those from M. mulatta. Results showed that there was general similarity in muscle presence/absence between the species as well as muscle form except for musculature around the external ear. M. mulatta had more musculature around the external ear than M. nigra. In addition, M. nigra lacked a zygomaticus minor while M. mulatta is reported to have one. These morphological differences match behavioral observations documenting a limited range of ear movements used by M. nigra during facial displays. Future studies focusing on a wider phylogenetic range of macaques with varying dominance styles may further elucidate the roles of phylogeny, ecology, and social variables in the evolution of mimetic muscles within Macaca Anat Rec, 299:1317-1324, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Ziarani, Ali S.; Aguilera, Roberto
2012-08-01
A new model is proposed for estimation of pore-throat aperture size from formation resistivity factor and permeability data. The model is validated with data from the Mesaverde sandstone using brine salinities ranging from 20,000 to 200,000 ppm. The data analyzed includes various basins such as Green River, Piceance, Sand Wash, Powder River, Uinta, Washakie and Wind River, available in the literature. For pore-throat radii analysis the methodology involves the use of log-log plots of pore-throat radius versus the product of formation resistivity factor and permeability (rT = a(FK)b + c). The model fits over 280 samples from the Mesaverde formation with coefficients of determination varying between 0.95 and 0.99 depending primarily on the type of model used for pore throat radius calculation. The brine salinity has some minor effects on the results. The model can provide better estimates of pore-throat radii if it is calibrated with experimental techniques such as mercury porosimetry. The results show pore-throat radii varying between 0.001 and 5 μm for the Mesaverde tight sandstone; however, most of the samples fall in a range between 0.01 and 1 μm. For tortuosity analysis, the calculation involves the use of product of formation factor and porosity data. Results indicate that the estimated tortuosity values range mainly between 1 and 5. For samples with lower porosities (< 5%), tortuosity values show a wider scatter (between 1 and 8); whereas for samples with larger porosities (> 15%), the scattering in tortuosity decreases significantly. In general, for tortuosity calculation in tight gas sandstone formations, a square root model with a parameter (bf) representing various types of connecting pores, i.e., sheet-like and tubular pores, is recommended.
Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee
A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. BMI was strongly correlated (R = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m could turn left and right within 91 cm and individuals with BMI up to 45 kg/m could turn one direction within 91 cm. BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m and should consider placing all patients greater than 45 kg/m on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients.
Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee
2017-01-01
Background A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. Objective The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Methods Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m2 participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. Results BMI was strongly correlated (R2 = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m2 could turn left and right within 91 cm and individuals with BMI up to 45 kg/m2 could turn one direction within 91 cm. Discussion BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m2 and should consider placing all patients greater than 45 kg/m2 on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients. PMID:28968285
Obiols-Rabasa, M; Ramos, J; Forcada, J; Esquena, J; Solans, C; Levecke, B; Booten, K; Tadros, Tharwat F
2010-06-01
The seeded semicontinuous emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BuA) stabilized with a graft polymeric surfactant based on inulin, INUTEC SP1, as well as its mixture with sodium lauryl sulfate (SLS) is described. The mixture of SLS and Brij58 (alcohol ethoxylated) and the mixture of SLS and Pluronic P85 (block copolymer PEO-PPO-PEO) are also used as surfactant systems. The addition of methacrylic acid (MAA) or acrylic acid (AA) as comonomers is also studied. Previous results proved this inulin-derivative surfactant, INUTEC SP1, to be very effective on synthesizing latexes using a very low surfactant concentration. The kinetic features of the emulsion polymerization (instantaneous conversion and total conversion) were gravimetrically determined along the reactions. Latex dispersions were characterized by photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) to obtain the average particle size, the particle size distributions (PSDs) as well as the polydispersity index (PdI). The stability was determined by turbidimetry measurements and expressed in terms of critical coagulation concentration. The results showed that the use of the graft polymeric surfactant allowed obtaining highly stable nanoparticles, at low surfactant concentrations and high solid contents (up to 37 wt %). This is an improvement with respect to previous works, in which a mixture of the graft polymeric surfactant with another surfactant was required to obtain stable nanoparticles with low polydispersity, at high solid content. In the present work, low polydispersity was achieved using INUTEC as the only emulsifier, which was related to the absence of secondary nucleations. When a mixture of INUTEC SP1 and SLS is used, a wider PSD is obtained due to secondary nucleations. Replacing INUTEC SP1 by other nonionic surfactants such as Brij58 or Pluronic P85 leads to an increase of average particle size and wider PSD.
Life on the edge: carnivore body size variation is all over the place
Meiri, Shai; Dayan, Tamar; Simberloff, Daniel; Grenyer, Richard
2009-01-01
Evolutionary biologists have long been fascinated by both the ways in which species respond to ecological conditions at the edges of their geographic ranges and the way that species' body sizes evolve across their ranges. Surprisingly, though, the relationship between these two phenomena is rarely studied. Here, we examine whether carnivore body size changes from the interior of their geographic range towards the range edges. We find that within species, body size often varies strongly with distance from the range edge. However, there is no general tendency across species for size to be either larger or smaller towards the edge. There is some evidence that the smallest guild members increase in size towards their range edges, but results for the largest guild members are equivocal. Whether individuals vary in relation to the distance from the range edges often depends on the way edge and interior are defined. Neither geographic range size nor absolute body size influences the tendency of size to vary with distance from the range edge. Therefore, we suggest that the frequent significant association between body size and the position of individuals along the edge-core continuum reflects the prevalence of geographic size variation and that the distance to range edge per se does not influence size evolution in a consistent way. PMID:19324818
Typlt, Marei; Englitz, Bernhard; Sonntag, Mandy; Dehmel, Susanne; Kopp-Scheinpflug, Cornelia; Ruebsamen, Rudolf
2012-01-01
Multiple parallel auditory pathways ascend from the cochlear nucleus. It is generally accepted that the origin of these pathways are distinct groups of neurons differing in their anatomical and physiological properties. In extracellular in vivo recordings these neurons are typically classified on the basis of their peri-stimulus time histogram. In the present study we reconsider the question of classification of neurons in the anteroventral cochlear nucleus (AVCN) by taking a wider range of response properties into account. The study aims at a better understanding of the AVCN's functional organization and its significance as the source of different ascending auditory pathways. The analyses were based on 223 neurons recorded in the AVCN of the Mongolian gerbil. The range of analysed parameters encompassed spontaneous activity, frequency coding, sound level coding, as well as temporal coding. In order to categorize the unit sample without any presumptions as to the relevance of certain response parameters, hierarchical cluster analysis and additional principal component analysis were employed which both allow a classification on the basis of a multitude of parameters simultaneously. Even with the presently considered wider range of parameters, high number of neurons and more advanced analytical methods, no clear boundaries emerged which would separate the neurons based on their physiology. At the current resolution of the analysis, we therefore conclude that the AVCN units more likely constitute a multi-dimensional continuum with different physiological characteristics manifested at different poles. However, more complex stimuli could be useful to uncover physiological differences in future studies. PMID:22253838
Gaidajis, George
2003-01-01
To assess ambient air quality at the wider area of TVX Hellas mining facilities, the Total Suspended Particulate matter (TSP) and its content in characteristic elements, i.e., As, Cd, Cu, Fe, Mn, Pb, Zn are being monitored for more than thirty months as part of the established Environmental Monitoring Program. High Volume air samplers equipped with Tissue Quartz filters were employed for the collection of TSP. Analyses were effected after digestion of the suspended particulate with an HNO3-HCl solution and determination of elemental concentrations with an Atomic Absorption Spectroscopy equipped with graphite furnace. The sampling stations were selected to record representatively the existing ambient air quality in the vicinity of the facilities and at remote sites not affected from industrial activities. Monitoring data indicated that the background TSP concentrations ranged from 5-60 microg/m3. Recorded TSP concentrations at the residential sites close to the facilities ranged between 20-100 microg/m3, indicating only a minimal influence from the mining and milling activities. Similar spatial variation was observed for the TSP constituents and specifically for Pb and Zn. To validate the monitoring procedures, a parallel sampling campaign took place with different High Volume samplers at days where low TSP concentrations were expected. The satisfactory agreement (+/- 11%) at low concentrations (50-100 microg/m3) clearly supported the reproducibility of the techniques employed specifically at the critical range of lower concentrations.
Meningitis in HIV-positive patients in sub-Saharan Africa: a review
Veltman, Jennifer A; Bristow, Claire C; Klausner, Jeffrey D
2014-01-01
Introduction Meningitis is one of the leading causes of death among patients living with HIV in sub-Saharan Africa. There is no widespread tracking of the incidence rates of causative agents among patients living with HIV, yet the aetiologies of meningitis are different than those of the general population. Methods We reviewed the scientific literature published in PubMed to determine the incidence rates of meningitis among hospitalized people living with HIV in sub-Saharan Africa and report our findings from seven studies across sub-Saharan Africa. Results We found high rates of cryptococcal meningitis (19–68%). Tuberculous meningitis was lower (1–36%), although some centres included possible cases as “other” meningitis; therefore, this may not be a true representation of the total cases. Pyogenic meningitis ranged from 6 to 30% and “other” meningitis ranged from 7 to 28% of all reported cases of meningitis. Mortality rates ranged from 25 to 68%. This review describes the most common aetiologies and provides practical diagnostic, treatment and prevention considerations as they apply to the individual living with HIV in sub-Saharan Africa. Conclusions Diagnosis is often limited, and wider availability of accurate and low-cost laboratory diagnostics is desperately needed for prompt diagnosis and initiation of appropriate treatment. Wider acceptance and adoption of available preventative modalities can decrease the incidence of potentially fatal central nervous system infections in African patients living with HIV. PMID:25308903
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-22
... shape. Such fruit, if it is wider than it is tall, is considered to be badly misshapen. Identification... the current parameters for misshapen fruit; from ``fruit that is not wider than tall'' to fruit that is a certain percentage wider than it is tall. This alternative would allow for flatter/wider fruit...
Evaluating the Wider Outcomes of Schools: Complex Systems Modelling for Leadership Decisioning
ERIC Educational Resources Information Center
Crick, Ruth Deakin; Barr, Steven; Green, Howard; Pedder, David
2017-01-01
A continuing challenge for the education system is how to evaluate the wider outcomes of schools. Wider measures of success--such as citizenship or lifelong learning--influence each other and emerge over time from complex interactions between students, teachers and leaders, and the wider community. Unless methods are found to evaluate these…