Solar Photothermal Disinfection using Broadband-Light Absorbing Gold Nanoparticles and Carbon Black.

Science.gov (United States)

Loeb, Stephanie; Li, Chuanhao; Kim, Jae-Hong

2018-01-02

A simple heat treatment, perhaps the most globally recognized point-of-use water sterilization method, is seemingly effective against all major pathogens of concern, but bulk water boiling is not energy efficient or sustainable. Herein, we present the first application of solar-to-thermal converting nanomaterials for the direct inactivation of bacteria and viruses in drinking water through the application of Au nanorods, carbon black, and Au nanorod-carbon black composite materials as light absorbers. With broad absorption bands spanning the visible and near-infrared wavelengths, at sufficient concentrations, these nanoparticles induce multiple scattering events, increasing photon absorption probability and concentrating the light within a small spatial domain, leading to localized, intense heating that inactivates microorganisms in close proximity. Moving toward practical device design, we have developed a facile silane immobilization approach to fabricate films with densely packed layers of photothermal nanomaterials. Our results suggest that upon irraditaion with simulated solar light, these films can thermally inactivate bacteria and viruses, as demonstrated through the inactivation of surrogate organisms Escherichia coli K-12, and bacteriophages MS2 and PR772.

Light escape cones in local reference frames of Kerr-de Sitter black hole spacetimes and related black hole shadows

Science.gov (United States)

Stuchlík, Zdeněk; Charbulák, Daniel; Schee, Jan

2018-03-01

We construct the light escape cones of isotropic spot sources of radiation residing in special classes of reference frames in the Kerr-de Sitter (KdS) black hole spacetimes, namely in the fundamental class of `non-geodesic' locally non-rotating reference frames (LNRFs), and two classes of `geodesic' frames, the radial geodesic frames (RGFs), both falling and escaping, and the frames related to the circular geodesic orbits (CGFs). We compare the cones constructed in a given position for the LNRFs, RGFs, and CGFs. We have shown that the photons locally counter-rotating relative to LNRFs with positive impact parameter and negative covariant energy are confined to the ergosphere region. Finally, we demonstrate that the light escaping cones govern the shadows of black holes located in front of a radiating screen, as seen by the observers in the considered frames. For shadows related to distant static observers the LNRFs are relevant.

Significant differences in maternal child-feeding style between ethnic groups in the UK: the role of deprivation and parenting styles.

Science.gov (United States)

Korani, M; Rea, D M; King, P F; Brown, A E

2018-04-03

Nonresponsive maternal child-feeding interactions, such as restricting, pressurising and emotional feeding, can affect the ability of a child to self-regulate intake and increase the risk of becoming overweight. However, despite findings that South Asian and Black children living in the UK are more likely to be overweight, UK research has not considered how maternal child-feeding style might differ between ethnic groups. The present study aimed to explore variations in maternal child-feeding style between ethnic groups in the UK, taking into account associated factors such as deprivation and parenting style. Six hundred and fifty-nine UK mothers with a child who was aged 5-11 years old completed a questionnaire. Items included ethnicity and demographic data, as well as copies of the Child Feeding Questionnaire, Parental Feeding Styles Questionnaire and Parenting Styles and Dimensions Questionnaire. Significant differences in perceived responsibility (P = 0.002), restriction (P = 0.026), pressure to eat (P = 0.045), instrumental feeding (P = 0.000) and emotional feeding (P = 0.000) were found between the groups. Mothers from South Asian backgrounds reported higher levels of pressure to eat, emotional feeding and indulgent feeding styles, whereas mothers from Chinese backgrounds reported greater perceived responsibility and restriction. Mothers from Black and White British backgrounds were not significantly higher with respect to any behaviour. Maternal child-feeding style was also associated with deprivation and parenting style, although these did not fully explain the data. Understanding cultural factors behind maternal child-feeding style, particularly around pressurising and indulgent feeding behaviours, may play an important part in reducing levels of children who are overweight and obese in the UK. © 2018 The British Dietetic Association Ltd.

arXiv Black hole superradiance and polarization-dependent bending of light

CERN Document Server

Plascencia, Alexis D.

2018-04-27

An inhomogeneous pseudo-scalar field configuration behaves like an optically active medium. Consequently, if a light ray passes through an axion cloud surrounding a Kerr black hole, it may experience a polarization-dependent bending. We explore the size and relevance of such effect considering both the QCD axion and a generic axion-like particle.

arXiv Black hole superradiance and polarization-dependent bending of light

CERN Document Server

Plascencia, Alexis D.

2017-01-01

An inhomogeneous pseudo-scalar field configuration behaves like an optically active medium. Consequently, if a light ray passes through an axion cloud surrounding a Kerr black hole, it may experience a polarization-dependent bending. We explore the size and relevance of such effect considering both the QCD axion and a generic axion-like particle.

Black-body radiation effects and light shifts in atomic frequency standards

Energy Technology Data Exchange (ETDEWEB)

Pal' chikov, V G; Domnin, Yu S; Novoselov, A V [Institute of Metrology for Time and Space at National Research Institute for Physical-Technical and Radiotechnical Measurements - IMVP GP VNIIFTRI, Mendeleevo, Moscow Region, 141570 (Russian Federation)

2003-04-01

A general method is presented for calculating the higher-order terms of series in powers of the black-body radiation field for the Stark-state wavefunctions, dipole transition matrix elements and corresponding frequency shifts of hyperfine splitting in the ground states for Cs and Rb atoms. A numerical method for calculating the light shifts in Sr atoms is described. It is based on the Green function method for summation over all intermediate states and exact Dirac-Fock wavefunctions for the resonant transitions to the first excited s-, p- and d-states. By comparing the calculated Stark shift with results of measurements employing atomic frequency standards, the black-body radiation effects on the ground state are analysed.

The mass of the black hole in 1A 0620-00, revisiting the ellipsoidal light curve modelling

Science.gov (United States)

van Grunsven, Theo F. J.; Jonker, Peter G.; Verbunt, Frank W. M.; Robinson, Edward L.

2017-12-01

The mass distribution of stellar-mass black holes can provide important clues to supernova modelling, but observationally it is still ill constrained. Therefore, it is of importance to make black hole mass measurements as accurate as possible. The X-ray transient 1A 0620-00 is well studied, with a published black hole mass of 6.61 ± 0.25 M⊙, based on an orbital inclination i of 51.0° ± 0.9°. This was obtained by Cantrell et al. (2010) as an average of independent fits to V-, I- and H-band light curves. In this work, we perform an independent check on the value of i by re-analysing existing YALO/SMARTS V-, I- and H-band photometry, using different modelling software and fitting strategy. Performing a fit to the three light curves simultaneously, we obtain a value for i of 54.1° ± 1.1°, resulting in a black hole mass of 5.86 ± 0.24 M⊙. Applying the same model to the light curves individually, we obtain 58.2° ± 1.9°, 53.6° ± 1.6° and 50.5° ± 2.2° for V-, I- and H-band, respectively, where the differences in best-fitting i are caused by the contribution of the residual accretion disc light in the three different bands. We conclude that the mass determination of this black hole may still be subject to systematic effects exceeding the statistical uncertainty. Obtaining more accurate masses would be greatly helped by continuous phase-resolved spectroscopic observations simultaneous with photometry.

Light propagation through black-hole lattices

Energy Technology Data Exchange (ETDEWEB)

Bentivegna, Eloisa [Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Via S. Sofia 64, 95123 Catania (Italy); Korzyński, Mikołaj [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Hinder, Ian; Gerlicher, Daniel, E-mail: eloisa.bentivegna@unict.it, E-mail: korzynski@cft.edu.pl, E-mail: ian.hinder@aei.mpg.de, E-mail: daniel.gerlicher@tum.de [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut, Am Mühlenberg 1, D-14476 Golm (Germany)

2017-03-01

The apparent properties of distant objects encode information about the way the light they emit propagates to an observer, and therefore about the curvature of the underlying spacetime. Measuring the relationship between the redshift z and the luminosity distance D {sub L} of a standard candle, for example, yields information on the Universe's matter content. In practice, however, in order to decode this information the observer needs to make an assumption about the functional form of the D {sub L}( z ) relation; in other words, a cosmological model needs to be assumed. In this work, we use numerical-relativity simulations, equipped with a new ray-tracing module, to numerically obtain this relation for a few black-hole-lattice cosmologies and compare it to the well-known Friedmann-Lema(ȋtre-Robertson-Walker case, as well as to other relevant cosmologies and to the Empty-Beam Approximation. We find that the latter provides the best estimate of the luminosity distance and formulate a simple argument to account for this agreement. We also find that a Friedmann-Lema(ȋtre-Robertson-Walker model can reproduce this observable exactly, as long as a time-dependent cosmological constant is included in the fit. Finally, the dependence of these results on the lattice mass-to-spacing ratio μ is discussed: we discover that, unlike the expansion rate, the D {sub L}( z ) relation in a black-hole lattice does not tend to that measured in the corresponding continuum spacetime as 0μ → .

"Styled by Their Perceptions": Black Adolescent Girls Interpret Representations of Black Females in Popular Culture

Science.gov (United States)

Muhammad, Gholnecsar E.; McArthur, Sherell A.

2015-01-01

Identity formation is a critical process shaping the lives of adolescents and can present distinct challenges for Black adolescent girls who are positioned in society to negotiate ideals of self when presented with false and incomplete images representing Black girlhood. Researchers have found distorted images of Black femininity derived from…

Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols

Directory of Open Access Journals (Sweden)

M. O. Andreae

2006-01-01

Full Text Available Although the definition and measurement techniques for atmospheric 'black carbon' ('BC' or 'elemental carbon'' ('EC' have long been subjects of scientific controversy, the recent discovery of light-absorbing carbon that is not black ('brown carbon, Cbrown' makes it imperative to reassess and redefine the components that make up light-absorbing carbonaceous matter (LAC in the atmosphere. Evidence for the atmospheric presence of Cbrown comes from (1 spectral aerosol light absorption measurements near specific combustion sources, (2 observations of spectral properties of water extracts of continental aerosol, (3 laboratory studies indicating the formation of light-absorbing organic matter in the atmosphere, and (4 indirectly from the chemical analogy of aerosol species to colored natural humic substances. We show that brown carbon may severely bias measurements of 'BC' and 'EC' over vast parts of the troposphere, especially those strongly polluted by biomass burning, where the mass concentration of Cbrown is high relative to that of soot carbon. Chemical measurements to determine 'EC' are biased by the refractory nature of Cbrown as well as by complex matrix interferences. Optical measurements of 'BC' suffer from a number of problems: (1 many of the presently used instruments introduce a substantial bias into the determination of aerosol light absorption, (2 there is no unique conversion factor between light absorption and 'EC' or 'BC' concentration in ambient aerosols, and (3 the difference in spectral properties between the different types of LAC, as well as the chemical complexity of Cbrown, lead to several conceptual as well as practical complications. We also suggest that due to the sharply increasing absorption of Cbrown towards the UV, single-wavelength light absorption measurements may not be adequate for the assessment of absorption of solar radiation in the troposphere. We discuss the possible consequences of these effects for our

Cultivating yeast in fractions of light oil from black coal resin. [Candida tropicalis

Energy Technology Data Exchange (ETDEWEB)

Kucher, R.V.; Pavlyuk, M.I.; Dzumedzei, N.V.; Turovskii, A.A.

1982-11-01

Feasibility of using a light fraction of black coal oil from the Avdeevskii coking plant as a substrate for growing microorganisms was studied. Candida tropicalis was adapted to the light oil in multiple stages and in continually changing conditions. Maximum growth of the yeast occurred in fractions of the oil with boiling points of 363, 373-293 K. It was demonstrated that low temperature fractions of the hard coal oil are a source of hydrocarbons and energy in microbiological processes. Surface-active materials, such as sodium lauryl sulfate and syntanol-15, stimulate the growth of the yeast in light oil fractions from hard coal resin. (5 refs.) (In Russian)

Testing the nature of the supermassive black hole candidate in SgrA* with light curves and images of hot spots

International Nuclear Information System (INIS)

Li, Zilong; Kong, Lingyao; Bambi, Cosimo

2014-01-01

General relativity makes clear predictions about the spacetime geometry around black holes. In the near future, new facilities will have the capability to explore the metric around SgrA*, the supermassive black hole candidate at the center of our Galaxy, and to open a new window to test the Kerr black hole hypothesis. In this paper, we compute light curves and images associated with compact emission regions (hot spots) orbiting around Kerr and non-Kerr black holes. We study how the analysis of the properties of the radiation emitted by a hot spot can be used to test the Kerr nature of SgrA*. We find that the sole observation of the hot spot light curve can at most constrain a combination of the black hole spin and of possible deviations from the Kerr solution. This happens because the same orbital frequency around a Kerr black hole can be found for a non-Kerr object with a different spin parameter. Second order corrections in the light curve due to the background geometry are typically too small to be identified. While the observation of the hot spot centroid track can potentially bound possible deviations from the Kerr solution, that is out of reach for the near future for the Very Large Telescope Interferometer instrument GRAVITY. The Kerr black hole hypothesis could really be tested in the case of the discovery of a radio pulsar in a compact orbit around SgrA*. Radio observations of such a pulsar would provide precise estimates of the mass and the spin of SgrA*, and the combination of these measurements (probing the weak field) with the hot spot light curve information (probing the strong field) may constrain/find possible deviations from the Kerr solution with quite good precision.

Testing the nature of the supermassive black hole candidate in SgrA* with light curves and images of hot spots

Energy Technology Data Exchange (ETDEWEB)

Li, Zilong; Kong, Lingyao; Bambi, Cosimo [Center for Field Theory and Particle Physics and Department of Physics, Fudan University, 200433 Shanghai (China)

2014-06-01

General relativity makes clear predictions about the spacetime geometry around black holes. In the near future, new facilities will have the capability to explore the metric around SgrA*, the supermassive black hole candidate at the center of our Galaxy, and to open a new window to test the Kerr black hole hypothesis. In this paper, we compute light curves and images associated with compact emission regions (hot spots) orbiting around Kerr and non-Kerr black holes. We study how the analysis of the properties of the radiation emitted by a hot spot can be used to test the Kerr nature of SgrA*. We find that the sole observation of the hot spot light curve can at most constrain a combination of the black hole spin and of possible deviations from the Kerr solution. This happens because the same orbital frequency around a Kerr black hole can be found for a non-Kerr object with a different spin parameter. Second order corrections in the light curve due to the background geometry are typically too small to be identified. While the observation of the hot spot centroid track can potentially bound possible deviations from the Kerr solution, that is out of reach for the near future for the Very Large Telescope Interferometer instrument GRAVITY. The Kerr black hole hypothesis could really be tested in the case of the discovery of a radio pulsar in a compact orbit around SgrA*. Radio observations of such a pulsar would provide precise estimates of the mass and the spin of SgrA*, and the combination of these measurements (probing the weak field) with the hot spot light curve information (probing the strong field) may constrain/find possible deviations from the Kerr solution with quite good precision.

The Effects of Light Intensity, Casing Layers, and Layering Styles on Royal Sun Medicinal Mushroom, Agaricus brasiliensis (Higher Basidiomycetes) Cultivation in Turkey.

Science.gov (United States)

Adanacioglu, Neşe; Boztok, Kaya; Akdeniz, Ramazan Cengiz

2015-01-01

The aim of this research is to evaluate the effects of light intensity, casing layers, and layering styles on the production of the culinary-medicinal mushroom Agaricus brasiliensis in Turkey. The experiments were designed in split-split plots and replicated twice. Three different light intensities-I1, 350 lux; I2, 450 lux; and I3, 750 lux-were used in main plots as environmental factors. A mixture of 4 different casing layers- peat (100%), peat-perlite (75%:25%), peat-clinoptilolite (75%:25%), and peat-perlite-clinoptilolite (60%:20%:20%)-were used at split plots and at split plots. S1, a flat, 3-cm casing layer; S2, a flat, 5-cm casing layer; and S3, casing soil ridges 10 cm wide × 4 cm high, 10 cm apart, were deposited on top of 1-cm overall soil casing layers. At the end of the harvest phase, the total yield was estimated per 100 kg of substrate. Biological efficiency (percentage) was determined from the fresh weight of the mushrooms and the dry weight of the compost at the end of the harvesting period. The highest total yield (7.2 kg/100 kg compost) and biological efficiency (27.63%) were achieved from I2 × peat-perlite-clinoptilolite × S2 treatment. Influence of light intensity, casing layer, layering style, and their interaction in treatments with color values (L*, a*, b*, chroma*, and hue*) also were examined. It has been shown that within color values, chroma* (saturation) values of mushroom caps were affected by light intensity, casing layer, and layering style treatments and light intensity × casing layer treatments and the brightness of mushroom caps tended to increase as light intensity increased.

Real-time black carbon emission factor measurements from light duty vehicles.

Science.gov (United States)

Forestieri, Sara D; Collier, Sonya; Kuwayama, Toshihiro; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D

2013-11-19

Eight light-duty gasoline low emission vehicles (LEV I) were tested on a Chassis dynamometer using the California Unified Cycle (UC) at the Haagen-Smit vehicle test facility at the California Air Resources Board in El Monte, CA during September 2011. The UC includes a cold start phase followed by a hot stabilized running phase. In addition, a light-duty gasoline LEV vehicle and ultralow emission vehicle (ULEV), and a light-duty diesel passenger vehicle and gasoline direct injection (GDI) vehicle were tested on a constant velocity driving cycle. A variety of instruments with response times ≥0.1 Hz were used to characterize how the emissions of the major particulate matter components varied for the LEVs during a typical driving cycle. This study focuses primarily on emissions of black carbon (BC). These measurements allowed for the determination of BC emission factors throughout the driving cycle, providing insights into the temporal variability of BC emission factors during different phases of a typical driving cycle.

Black Hole Grabs Starry Snack

Science.gov (United States)

2006-01-01

[figure removed for brevity, see original site] Poster Version This artist's concept shows a supermassive black hole at the center of a remote galaxy digesting the remnants of a star. NASA's Galaxy Evolution Explorer had a 'ringside' seat for this feeding frenzy, using its ultraviolet eyes to study the process from beginning to end. The artist's concept chronicles the star being ripped apart and swallowed by the cosmic beast over time. First, the intact sun-like star (left) ventures too close to the black hole, and its own self-gravity is overwhelmed by the black hole's gravity. The star then stretches apart (middle yellow blob) and eventually breaks into stellar crumbs, some of which swirl into the black hole (cloudy ring at right). This doomed material heats up and radiates light, including ultraviolet light, before disappearing forever into the black hole. The Galaxy Evolution Explorer was able to watch this process unfold by observing changes in ultraviolet light. The area around the black hole appears warped because the gravity of the black hole acts like a lens, twisting and distorting light.

An asymptotically consistent approximant for the equatorial bending angle of light due to Kerr black holes

Science.gov (United States)

Barlow, Nathaniel S.; Weinstein, Steven J.; Faber, Joshua A.

2017-07-01

An accurate closed-form expression is provided to predict the bending angle of light as a function of impact parameter for equatorial orbits around Kerr black holes of arbitrary spin. This expression is constructed by assuring that the weak- and strong-deflection limits are explicitly satisfied while maintaining accuracy at intermediate values of impact parameter via the method of asymptotic approximants (Barlow et al 2017 Q. J. Mech. Appl. Math. 70 21-48). To this end, the strong deflection limit for a prograde orbit around an extremal black hole is examined, and the full non-vanishing asymptotic behavior is determined. The derived approximant may be an attractive alternative to computationally expensive elliptical integrals used in black hole simulations.

Gakumon-Ryoku and japanese style of management- does our management style matter?

Directory of Open Access Journals (Sweden)

Oba Hiroyuki

2010-05-01

Full Text Available This paper highlights a new style of development learning, the so-called “Gakumon-ryoku”, and its application to the Japanese style of management. “Gakumon-ryoku” is the capability and commitment or free-will to awaken and share freedom lifestyles by learning and asking about our thoughts and feelings through the Value-Conscious Matrix VC Matrix or simply VCM for short.This enlightens and vitalizes our thoughts and feelings, and can transform us by creating a new identity for us as Development of Co-creative Alive Beings, or D-CAB. This eye-opening experience was examined with the Japanese style of management (JM in short and has brought us to become aware of the essence of JM spirit of TO BE ONE. To the question, “does our management style matter”, this paper has answered “Yes”, not because this is not economically or rationally efficient, but because it has been confined to it and has not been examined in the light of the JOY criterion including efficiency. What really matters is not whether or not to follow the Japanese style, but the fact that the quality of life, or Joyful or not matters in our management style. We learn that the Japanese style of management has both unique and universal features, and we, as human beings, can share its universal value of JOY of service.

Learning templates for artistic portrait lighting analysis.

Science.gov (United States)

Chen, Xiaowu; Jin, Xin; Wu, Hongyu; Zhao, Qinping

2015-02-01

Lighting is a key factor in creating impressive artistic portraits. In this paper, we propose to analyze portrait lighting by learning templates of lighting styles. Inspired by the experience of artists, we first define several novel features that describe the local contrasts in various face regions. The most informative features are then selected with a stepwise feature pursuit algorithm to derive the templates of various lighting styles. After that, the matching scores that measure the similarity between a testing portrait and those templates are calculated for lighting style classification. Furthermore, we train a regression model by the subjective scores and the feature responses of a template to predict the score of a portrait lighting quality. Based on the templates, a novel face illumination descriptor is defined to measure the difference between two portrait lightings. Experimental results show that the learned templates can well describe the lighting styles, whereas the proposed approach can assess the lighting quality of artistic portraits as human being does.

The relationship between perceived parenting styles and resilience ...

African Journals Online (AJOL)

Results — Authoritative parenting provided the most significant contribution to the explanation of the variance in resilience for black and white adolescents, and both genders. Surprisingly, the findings suggest that there is a positive relationship between fathers' authoritarian styles and emotion-focused coping strategies in ...

An asymptotically consistent approximant for the equatorial bending angle of light due to Kerr black holes

International Nuclear Information System (INIS)

Barlow, Nathaniel S; Faber, Joshua A; Weinstein, Steven J

2017-01-01

An accurate closed-form expression is provided to predict the bending angle of light as a function of impact parameter for equatorial orbits around Kerr black holes of arbitrary spin. This expression is constructed by assuring that the weak- and strong-deflection limits are explicitly satisfied while maintaining accuracy at intermediate values of impact parameter via the method of asymptotic approximants (Barlow et al 2017 Q. J. Mech. Appl. Math . 70 21–48). To this end, the strong deflection limit for a prograde orbit around an extremal black hole is examined, and the full non-vanishing asymptotic behavior is determined. The derived approximant may be an attractive alternative to computationally expensive elliptical integrals used in black hole simulations. (paper)

Some Observations about Leaders in the Black Community

Directory of Open Access Journals (Sweden)

Joseph S. Himes

2010-10-01

Full Text Available In a paper not previously published, the founding president of the North Carolina Sociological Association explores changing leadership styles among black leaders. By the 1960s, when this paper was written as a thought piece, leadership patterns had changed from those embeded in local institutions towards leaders who could master complex legal issues. Four leadership styles are found and discussed.

Monitoring Disaster-Related Power Outages Using NASA Black Marble Nighttime Light Product

Science.gov (United States)

Wang, Z.; Román, M. O.; Sun, Q.; Molthan, A. L.; Schultz, L. A.; Kalb, V. L.

2018-04-01

Timely and accurate monitoring of disruptions to the electricity grid, including the magnitude, spatial extent, timing, and duration of net power losses, is needed to improve situational awareness of disaster response and long-term recovery efforts. Satellite-derived Nighttime Lights (NTL) provide an indication of human activity patterns and have been successfully used to monitor disaster-related power outages. The global 500 m spatial resolution National Aeronautics and Space Administration (NASA) Black Marble NTL daily standard product suite (VNP46) is generated from Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) onboard the NASA/National Oceanic and Atmospheric Administration (NOAA) Suomi National Polar-orbiting Partnership (Suomi- NPP) satellite, which began operations on 19 January 2012. With its improvements in product accuracy (including critical atmospheric and BRDF correction routines), the VIIRS daily Black Mable product enables systematic monitoring of outage conditions across all stages of the disaster management cycle.

The Relationship between Family Environment and Parenting Style: A Preliminary Study of African American Families.

Science.gov (United States)

Hill, Nancy E.

1995-01-01

The influence of parenting style on aspects of family environment was studied with 174 9th graders, 11th graders and college freshmen (96% African American). Findings demonstrate that types of parenting styles are significantly related to outcome measures of family environment as predicted. Implications of authoritative parenting among blacks are…

MONITORING DISASTER-RELATED POWER OUTAGES USING NASA BLACK MARBLE NIGHTTIME LIGHT PRODUCT

Directory of Open Access Journals (Sweden)

Z. Wang

2018-04-01

Full Text Available Timely and accurate monitoring of disruptions to the electricity grid, including the magnitude, spatial extent, timing, and duration of net power losses, is needed to improve situational awareness of disaster response and long-term recovery efforts. Satellite-derived Nighttime Lights (NTL provide an indication of human activity patterns and have been successfully used to monitor disaster-related power outages. The global 500 m spatial resolution National Aeronautics and Space Administration (NASA Black Marble NTL daily standard product suite (VNP46 is generated from Visible Infrared Imaging Radiometer Suite (VIIRS Day/Night Band (DNB onboard the NASA/National Oceanic and Atmospheric Administration (NOAA Suomi National Polar-orbiting Partnership (Suomi- NPP satellite, which began operations on 19 January 2012. With its improvements in product accuracy (including critical atmospheric and BRDF correction routines, the VIIRS daily Black Mable product enables systematic monitoring of outage conditions across all stages of the disaster management cycle.

The Relationship of Field Dependent/Independent Cognitive Styles, Stimuli Variability and Time Factor on Student Achievement.

Science.gov (United States)

Atang, Christopher I.

The effects of black and white and color illustrations on student achievement were studied to investigate the relationships between cognitive styles and instructional design. Field dependence (FD) and field independence (FI) were chosen as the cognitive style variables. Subjects were 85 freshman students in the Iowa State University Psychology…

Texting Styles and Information Change of SMS Text Messages in Filipino

Science.gov (United States)

Cabatbat, Josephine Jill T.; Tapang, Giovanni A.

2013-02-01

We identify the different styles of texting in Filipino short message service (SMS) texts and analyze the change in unigram and bigram frequencies due to these styles. Style preference vectors for sample texts were calculated and used to identify the style combination used by an average individual. The change in Shannon entropy of the SMS text is explained in light of a coding process.

Ghetto Fabulous: Reading Black Adolescent Femininity in Contemporary Urban Street Fiction

Science.gov (United States)

Marshall, Elizabeth; Staples, Jeanine; Gibson, Simone

2009-01-01

In this article the authors provide a general overview of the controversies associated with urban street fiction, a brief introduction to the genre and an introduction to the complex representations of Black adolescent femininity within two contemporary titles, "Black and Ugly" (Styles, 2006) and "Bitch" (King, 2006). The authors provide a…

Low-mass black holes as the remnants of primordial black hole formation.

Science.gov (United States)

Greene, Jenny E

2012-01-01

Bridging the gap between the approximately ten solar mass 'stellar mass' black holes and the 'supermassive' black holes of millions to billions of solar masses are the elusive 'intermediate-mass' black holes. Their discovery is key to understanding whether supermassive black holes can grow from stellar-mass black holes or whether a more exotic process accelerated their growth soon after the Big Bang. Currently, tentative evidence suggests that the progenitors of supermassive black holes were formed as ∼10(4)-10(5) M(⊙) black holes via the direct collapse of gas. Ongoing searches for intermediate-mass black holes at galaxy centres will help shed light on this formation mechanism.

Influences and Retentions of West African Musical Concepts in U.S. Black Music.

Science.gov (United States)

Maultsby, Portia K.

1979-01-01

Current research reveals that West African musical concepts provided the foundation for the various musical genres created by Black Americans. The Black musical tradition continues to evolve and mirror new values, attitudes, philosophies, and life-styles without the loss of a West African identity. (RLV)

Novel concept of the smart NIR-light-controlled drug release of black phosphorus nanostructure for cancer therapy.

Science.gov (United States)

Qiu, Meng; Wang, Dou; Liang, Weiyuan; Liu, Liping; Zhang, Yin; Chen, Xing; Sang, David Kipkemoi; Xing, Chenyang; Li, Zhongjun; Dong, Biqin; Xing, Feng; Fan, Dianyuan; Bao, Shiyun; Zhang, Han; Cao, Yihai

2018-01-16

A biodegradable drug delivery system (DDS) is one the most promising therapeutic strategies for cancer therapy. Here, we propose a unique concept of light activation of black phosphorus (BP) at hydrogel nanostructures for cancer therapy. A photosensitizer converts light into heat that softens and melts drug-loaded hydrogel-based nanostructures. Drug release rates can be accurately controlled by light intensity, exposure duration, BP concentration, and hydrogel composition. Owing to sufficiently deep penetration of near-infrared (NIR) light through tissues, our BP-based system shows high therapeutic efficacy for treatment of s.c. cancers. Importantly, our drug delivery system is completely harmless and degradable in vivo. Together, our work proposes a unique concept for precision cancer therapy by external light excitation to release cancer drugs. If these findings are successfully translated into the clinic, millions of patients with cancer will benefit from our work.

The distribution of stars around the Milky Way's central black hole. II. Diffuse light from sub-giants and dwarfs

Science.gov (United States)

Schödel, R.; Gallego-Cano, E.; Dong, H.; Nogueras-Lara, F.; Gallego-Calvente, A. T.; Amaro-Seoane, P.; Baumgardt, H.

2018-01-01

Context. This is the second of three papers that search for the predicted stellar cusp around the Milky Way's central black hole, Sagittarius A*, with new data and methods. Aims: We aim to infer the distribution of the faintest stellar population currently accessible through observations around Sagittarius A*. Methods: We used adaptive optics assisted high angular resolution images obtained with the NACO instrument at the ESO VLT. Through optimised PSF fitting we removed the light from all detected stars above a given magnitude limit. Subsequently we analysed the remaining, diffuse light density. Systematic uncertainties were constrained by the use of data from different observing epochs and obtained with different filters. We show that it is necessary to correct for the diffuse emission from the mini-spiral, which would otherwise lead to a systematically biased light density profile. We used a Paschen α map obtained with the Hubble Space Telescope for this purpose. Results: The azimuthally averaged diffuse surface light density profile within a projected distance of R ≲ 0.5 pc from Sagittarius A* can be described consistently by a single power law with an exponent of Γ = 0.26 ± 0.02stat ± 0.05sys, similar to what has been found for the surface number density of faint stars in Paper I. Conclusions: The analysed diffuse light arises from sub-giant and main-sequence stars with Ks ≈ 19-22 with masses of 0.8-1.5 M⊙. These stars can be old enough to be dynamically relaxed. The observed power-law profile and its slope are consistent with the existence of a relaxed stellar cusp around the Milky Way's central black hole. We find that a Nuker law provides an adequate description of the nuclear cluster's intrinsic shape (assuming spherical symmetry). The 3D power-law slope near Sgr A* is γ = 1.13 ± 0.03model ± 0.05sys. The stellar density decreases more steeply beyond a break radius of about 3 pc, which corresponds roughly to the radius of influence of the

Parenting styles and body mass index trajectories from adolescence to adulthood.

Science.gov (United States)

Fuemmeler, Bernard F; Yang, Chongming; Costanzo, Phil; Hoyle, Rick H; Siegler, Ilene C; Williams, Redford B; Ostbye, Truls

2012-07-01

Parenting styles such as authoritarian, disengaged, or permissive are thought to be associated with greater adolescent obesity risk than an authoritative style. This study assessed the relationship between parenting styles and changes in body mass index (BMI) from adolescence to young adulthood. The study included self-reported data from adolescents in the National Longitudinal Study of Adolescent Health. Factor mixture modeling, a data-driven approach, was used to classify participants into parenting style groups based on measures of acceptance and control. Latent growth modeling (LGM) identified patterns of developmental changes in BMI. After a number of potential confounders were controlled for, parenting style variables were entered as predictors of BMI trajectories. Analyses were also conducted for male and female individuals of 3 racial-ethnic groups (Hispanic, black, white) to assess whether parenting styles were differentially associated with BMI trajectories in these 6 groups. Parenting styles were classified into 4 groups: authoritarian, disengaged, permissive, and balanced. Compared with the balanced parenting style, authoritarian and disengaged parenting styles were associated with a less steep average BMI increase (linear slope) over time, but also less leveling off (quadratic) of BMI over time. Differences in BMI trajectories were observed for various genders and races, but the differences did not reach statistical significance. Adolescents who reported having parents with authoritarian or disengaged parenting styles had greater increases in BMI as they transitioned to young adulthood despite having a lower BMI trajectory through adolescence.

Parenting Styles and Body Mass Index Trajectories From Adolescence to Adulthood

Science.gov (United States)

Fuemmeler, Bernard F.; Yang, Chongming; Costanzo, Phil; Hoyle, Rick H.; Ph.D.; Siegler, Ilene C.; Williams, Redford B.; Østbye, Truls

2013-01-01

Objective Parenting styles such as authoritarian, disengaged, or permissive are thought to be associated with greater adolescent obesity risk than an authoritative style. This study assessed the relationship between parenting styles and changes in body mass index (BMI) from adolescence to young adulthood. Methods The study included self-reported data from adolescents in the National Longitudinal Study of Adolescent Health. Factor mixture modeling, a data-driven approach, was used to classify participants into parenting style groups based on measures of acceptance and control. Latent growth modeling (LGM) identified patterns of developmental changes in BMI. After a number of potential cofounders were controlled for, parenting style variables were entered as predictors of BMI trajectories. Analyses were also conducted for males and females of three racial/ethnic groups (Hispanic, black, white) to assess whether parenting styles were differentially associated with BMI trajectories in these 6 groups. Results Parenting styles were classified into 4 groups: authoritarian, disengaged, permissive, and balanced. Compared with the balanced parenting style, authoritarian and disengaged parenting styles were associated with a less steep average BMI increase (linear slope) over time, but also less leveling off (quadratic) of BMI over time. Differences in BMI trajectories were observed for various genders and races, but the differences did not reach statistical significance. Conclusions Adolescents who reported having parents with authoritarian or disengaged parenting styles had greater increases in BMI as they transitioned to young adulthood despite having a lower BMI trajectory through adolescence. PMID:22545979

a perspective on the actions of olaf bergh's black scouts at smaldeel

African Journals Online (AJOL)

Steenkamp Fonseca R

This development put the black population in the position to challenge white rule. This challenge took the form ..... Van Schalkwyk was shot execution style through his eyes from a very close range.27. There were also ... It is important, however, to put the participation of these black units and the individuals who belonged to ...

Use of black light traps to monitor the abundance, spread, and flight behavior of Halyomorpha halys (Hemiptera: Pentatomidae).

Science.gov (United States)

Nielsen, Anne L; Holmstrom, Kristian; Hamilton, George C; Cambridge, John; Ingerson-Mahar, Joseph

2013-06-01

Monitoring the distribution and abundance of an invasive species is challenging, especially during the initial years of spread when population densities are low and basic biology and monitoring methods are being investigated. Brown marmorated stink bug (Halyomorpha halys (Stål)) is an invasive agricultural and urban pest that was first detected in the United States in the late 1990s. At the time of its detection, no method was available to effectively track H. halys populations, which are highly mobile and polyphagous. One possible solution was the utilization of black light traps, which are nonspecific traps attractive to night flying insects. To determine if black light traps are a reliable monitoring tool for H. halys, a state-wide network of 40-75 traps located on New Jersey farms were monitored from 2004 to 2011 for H. halys. This proved to be a highly effective method of monitoring H. halys populations and their spread at the landscape level. The total number of brown marmorated stink bug caught in New Jersey increased exponentially during this period at a rate of 75% per year. Logistic regression estimates that 2.84 new farms are invaded each year by H. halys. The results indicate that black light traps are attractive to early season populations as well as at low population densities. Weekly trap catch data are being used to generate state-wide population distribution maps made available to farmers in weekly newsletters and online. While no economic threshold currently exists for brown marmorated stink bug, the maps provide farmers with a tool to forecast pest pressure and plan management.

"Tangible Lights"

DEFF Research Database (Denmark)

Sørensen, Tor; Merritt, Timothy; Andersen, Oskar

2015-01-01

While there has been much focus on tangible lighting interfaces embedded in physical objects and smartphones as remote control, there has not been sufficient attention on how the expressivity of bodily movement can be used when designing interactions with light. Therefore, we investigate...... interaction with lighting technology beyond the smartphone and physical controllers. We examine the usefulness of the in-air gestural interaction style for lighting control. We bring forward "Tangible Lights", which serves as a novel interface for in-air interaction with lighting, drawing on existing...

Racial differences in parenting style typologies and heavy episodic drinking trajectories.

Science.gov (United States)

Clark, Trenette T; Yang, Chongming; McClernon, F Joseph; Fuemmeler, Bernard F

2015-07-01

This study examines racial differences between Whites and Blacks in the association of parenting style typologies with changes in heavy episodic drinking from adolescence to young adulthood. The analytic sample consists of 9,942 adolescents drawn from the National Longitudinal Study of Adolescent Health, which followed respondents from ages 12 to 31 years. Confirmatory factor analysis and factor mixture modeling are used to classify parenting style typologies based on measures of parental acceptance and control. Heavy Episodic Drinking (HED) trajectories are evaluated using a zero-inflated Poisson multigroup latent growth curve modeling approach. The mixture model identified 4 heterogeneous groups that differed based on the 2 latent variables (parental acceptance and control): balanced (65.8% of the sample), authoritarian (12.2%), permissive (19.4%), and uninvolved or neglectful (2.7%). Regardless of race, we found that at age 12 years, children of authoritarian parents have a higher probability of not engaging in HED than children of parents with balanced, permissive, or neglectful parenting styles. However, among Black youth who reported HED at age 12, authoritarian parenting was associated with greater level of HED at age 12 but a less steep increase in level of HED as age increased yearly as compared with balanced parenting. For White adolescents, uninvolved, permissive, and authoritarian parenting were not associated with a greater level of HED as age increased yearly as compared with adolescents exposed to balanced parenting. The influence of parenting styles on HED during adolescence persists into young adulthood and differs by race for youth engaging in HED. (c) 2015 APA, all rights reserved.

The influence of light, stream gradient, and iron on Didymosphenia geminata bloom development in the Black Hills, South Dakota

Science.gov (United States)

James, Daniel A.; Mosel, Kyle; Chipps, Steven R.

2014-01-01

The aquatic nuisance species Didymosphenia geminata was first documented in Rapid Creek of South Dakota’s Black Hills during 2002. Since then, blooms have occurred primarily in a 39-km section of Rapid Creek while blooms were rarely observed in other Black Hills streams. In this study, we evaluated factors related to the presence and development of visible colonies of D. geminata in four streams of the Black Hills. At the watershed scale, stream gradient was negatively associated with the occurrence of D. geminata whereas stream width was positively related to D. geminata presence. At the stream scale, D. geminata coverage was inversely related to canopy coverage and iron concentration. At the local scale, shading by bridges virtually eliminated growth of D. geminata colonies under bridges. At all three scales, proxy measures of light such as stream width, canopy coverage, and bridge shading revealed that light availability was an important factor influencing the presence and coverage of D. geminata colonies. In general, streams that had relatively wide stream reaches (mean = 9.9 m), shallow gradients (mean = 0.22%), and little canopy cover (mean = 13%) were associated with D. geminata blooms. In addition, iron concentrations in streams with D. geminata colonies were lower than in streams without blooms.

Light, Gravity and Black Holes

Science.gov (United States)

Falla, David

2012-01-01

The nature of light and how it is affected by gravity is discussed. Einstein's prediction of the deflection of light as it passes near the Sun was verified by observations made during the solar eclipse of 1919. Another prediction was that of gravitational redshift, which occurs when light emitted by a star loses energy in the gravitational field…

Style in knitted textiles and fashion

Science.gov (United States)

Štemberger, M.; Pavko-Čuden, A.

2017-10-01

The presented research relates the basic elements of the art theory with the concept of style and fashion design. The objective of the research was to determine how style is manifested in knitting in different periods of fashion seasons. The collections of three designers were compared: Missoni, Issey Miyake and Sonia Rykiel, in four different seasons in three different years. The basic artistic elements used in the presented research were: point, line, light-dark and colour together with syntactic rules. A combination of different elements and syntactic rules refers to different artistic languages, which have their own artistic grammar, i.e. a different style. All three investigated fashion designers used knitting in their collections as a significant element which defined their style. Different knitting technologies as well as different yarns made of synthetic or natural fibres in all colour spectra significantly influence the surface of a knitted fabric. Even when the technology is the same, the use of different materials, structures, colours, etc. creates various unique surfaces. The method used in the presented research was a style matrix which is developed from the axiomatic system. Only the part dealing with the language of fine arts and the pictorial speech - the style of a certain designer and a certain work of art/knitted fabric was used. After the selected three designers were examined through all the periods, it was concluded that each designer can be characterised by his own style. Despite the influencing fashion trends, all the compared designers still retained their own style, their own techniques, their own inspirations.

PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black.

Science.gov (United States)

Nzaba, Sarre Kadia Myra; Ntsendwana, Bulelwa; Mamba, Bhekie Brilliance; Kuvarega, Alex Tawanda

2018-05-01

This study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal co-doped TiO 2 . N,Pt co-doped TiO 2 photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PG0) as a template and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet/visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25, revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N,Pt co-doped TiO 2 was measured by the reaction of photocatalytic degradation of BB dye. Enhanced photodegradation efficiency of BB was achieved after 180-min reaction time with an initial concentration of 50 ppm. This was attributed to the rod-like shape of the materials, larger surface area, and enhanced absorption of visible light induced by N,Pt co-doping. The N,Pt co-doped TiO 2 also exhibited pseudo-first-order kinetic behavior with half-life and rate constant of 0.37 and 0.01984 min -1 , respectively. The mechanism of the photodegradation of BB under the visible light irradiation was proposed. The obtained results prove that co-doping of TiO 2 with N and Pt contributed to the enhanced photocatalytic performances of TiO 2 for visible light-induced photodegradation of organic contaminants for environmental remediation. Therefore, this work provides a new approach to the synthesis of PAMAM templated N,Pt co-doped TiO 2 for visible light photodegradation of brilliant black.

Black holes and beyond

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-02-01

Belief in the existence of black holes is the ultimate act of faith for a physicist. First suggested by the English clergyman John Michell in the year 1784, the gravitational pull of a black hole is so strong that nothing - not even light - can escape. Gravity might be the weakest of the fundamental forces but black-hole physics is not for the faint-hearted. Black holes present obvious problems for would-be observers because they cannot, by definition, be seen with conventional telescopes - although before the end of the decade gravitational-wave detectors should be able to study collisions between black holes. Until then astronomers can only infer the existence of a black hole from its gravitational influence on other matter, or from the X-rays emitted by gas and dust as they are dragged into the black hole. However, once this material passes through the 'event horizon' that surrounds the black hole, we will never see it again - not even with X-ray specs. Despite these observational problems, most physicists and astronomers believe that black holes do exist. Small black holes a few kilometres across are thought to form when stars weighing more than about two solar masses collapse under the weight of their own gravity, while supermassive black holes weighing millions of solar masses appear to be present at the centre of most galaxies. Moreover, some brave physicists have proposed ways to make black holes - or at least event horizons - in the laboratory. The basic idea behind these 'artificial black holes' is not to compress a large amount of mass into a small volume, but to reduce the speed of light in a moving medium to less than the speed of the medium and so create an event horizon. The parallels with real black holes are not exact but the experiments could shed new light on a variety of phenomena. The first challenge, however, is to get money for the research. One year on from a high-profile meeting on artificial black holes in London, for

Investigation of black and brown carbon multiple-wavelength-dependent light absorption from biomass and fossil fuel combustion source emissions

Science.gov (United States)

Michael R. Olson; Mercedes Victoria Garcia; Michael A. Robinson; Paul Van Rooy; Mark A. Dietenberger; Michael Bergin; James Jay Schauer

2015-01-01

Quantification of the black carbon (BC) and brown carbon (BrC) components of source emissions is critical to understanding the impact combustion aerosols have on atmospheric light absorption. Multiple-wavelength absorption was measured from fuels including wood, agricultural biomass, coals, plant matter, and petroleum distillates in controlled combustion settings....

Detection of Enhanced Central Mass-to-light Ratios in Low-mass Early-type Galaxies: Evidence for Black Holes?

Science.gov (United States)

Pechetti, Renuka; Seth, Anil; Cappellari, Michele; McDermid, Richard; den Brok, Mark; Mieske, Steffen; Strader, Jay

2017-11-01

We present dynamical measurements of the central mass-to-light ratio (M/L) of a sample of 27 low-mass early-type {{ATLAS}}3{{D}} galaxies. We consider all {{ATLAS}}3{{D}} galaxies with 9.7 text{}}M/L{{s}} are higher than dynamical {\\text{}}M/L{{s}} derived at larger radii and stellar population estimates of the galaxy centers in ˜80% of galaxies, with a median enhancement of ˜14% and a statistical significance of 3.3σ. We show that the enhancement in the central M/L is best described either by the presence of black holes in these galaxies or by radial initial mass function variations. Assuming a black hole model, we derive black hole masses for the sample of galaxies. In two galaxies, NGC 4458 and NGC 4660, the data suggest significantly overmassive black holes, while in most others only upper limits are obtained. We also show that the level of M/L enhancements we see in these early-type galaxy nuclei are consistent with the larger enhancements seen in ultracompact dwarf galaxies (UCDs), supporting the scenario where massive UCDs are created by stripping galaxies of these masses.

The Effects of Pictorial Complexity and Cognitive Style on Visual Recall Memory.

Science.gov (United States)

Jesky, Romaine R.; Berry, Louis H.

The effect of the interaction between cognitive style differences (field dependence/field independence) and various degrees of visual complexity on pictorial recall memory was explored using three sets of visuals in three different formats--line drawing, black and white, and color. The subjects were 86 undergraduate students enrolled in two core…

X-ray emission fluorescence (XRF) analysis of origin of raw materials of light dark reddish brown porcelain and porcelain with black flower on a white background of Dangyangyu kiln

International Nuclear Information System (INIS)

Zhang Hongyu; Yang Dawei; Guo Wenyu

2009-01-01

Dangyangyu kiln was an important civil porcelain production place in the North China during the Song Dynasty. In order to find out the source of raw materials of the porcelain body and glaze and their classification relationship so as to correctly distinguish them, we have used XRF to determine the major chemical elements of some porcelain samples with light brown and samples with black flower on a white background. Dynamic fuzzy cluster analysis was applied to the data. Results indicate that the origin of raw materials of light brown porcelain body samples is comparatively more concentrated, while that of the porcelain with black flower on a white background is scattered about. The origin of the body materials of those two kinds of porcelain samples is obviously different. The origin of raw materials of light brown porcelain samples is comparatively concentrated and stable, while that of the porcelain with black flower on a white background is scattered about, moreover, the origin of glaze raw materials and the formula of the two kinds are obviously different. The origin and formula of the light brown porcelain with white glaze in the interior are close to those of the white glaze of porcelain with black flower on a white background, but they are not entirely identical. (author)

Black Carbon and Kerosene Lighting: An Opportunity for Rapid Action on Climate Change and Clean Energy for Development

Energy Technology Data Exchange (ETDEWEB)

Jacobson, Arne [Humboldt State Univ., MN (United States). Schatz Energy Research Center; Bond, Tami C. [Univ. of Illinois at Urbana-Champaign, IL (United States). Dept. of Civil and Environmental Engineering; Lam, Nicholoas L. [Univ. of California, Berkeley, CA (United States). Dept. of Environmental Health Sciences; Hultman, Nathan [The Brookings Institution, Washington, DC (United States)

2013-04-15

Replacing inefficient kerosene lighting with electric lighting or other clean alternatives can rapidly achieve development and energy access goals, save money and reduce climate warming. Many of the 250 million households that lack reliable access to electricity rely on inefficient and dangerous simple wick lamps and other kerosene-fueled light sources, using 4 to 25 billion liters of kerosene annually to meet basic lighting needs. Kerosene costs can be a significant household expense and subsidies are expensive. New information on kerosene lamp emissions reveals that their climate impacts are substantial. Eliminating current annual black carbon emissions would provide a climate benefit equivalent to 5 gigatons of carbon dioxide reductions over the next 20 years. Robust and low-cost technologies for supplanting simple wick and other kerosene-fueled lamps exist and are easily distributed and scalable. Improving household lighting offers a low-cost opportunity to improve development, cool the climate and reduce costs.

Lifetime of Nano-Structured Black Silicon for Photovoltaic Applications

DEFF Research Database (Denmark)

Plakhotnyuk, Maksym; Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk

2016-01-01

In this work, we present recent results of lifetime optimization for nano-structured black silicon and its photovoltaic applications. Black silicon nano-structures provide significant reduction of silicon surface reflection due to highly corrugated nanostructures with excellent light trapping pro......, respectively. This is promising for use of black silicon RIE nano-structuring in a solar cell process flow......In this work, we present recent results of lifetime optimization for nano-structured black silicon and its photovoltaic applications. Black silicon nano-structures provide significant reduction of silicon surface reflection due to highly corrugated nanostructures with excellent light trapping...

Affective Style, Humor Styles and Happiness

Directory of Open Access Journals (Sweden)

Thomas E. Ford

2014-08-01

Full Text Available The present study examined the relationships between dispositional approach and avoidance motives, humor styles, and happiness. In keeping with previous research, approach motives and the two positive humor styles (self-enhancing and affiliative positively correlated with happiness, whereas avoidance motives and the two negative humor styles (self-defeating and aggressive negatively correlated with happiness. Also, we found support for three new hypotheses. First, approach motives correlated positively with self-enhancing and affiliative humor styles. Second, avoidance motives correlated positively with self-defeating humor style, and third, the positive relationship between approach motives and happiness was mediated by self-enhancing humor style.

Towards the theory of mini black holes with subplanckian mass

International Nuclear Information System (INIS)

Zeldovich, Y.B.

1984-01-01

This chapter phenomenologically examines the question of the decay (evaporation) and formation of mini black holes. Neutral black holes are considered, having neither electrical charge, nor color and weak charge, so that no long range vector field is present beyond gravitational radius. Topics considered include thermodynamic equilibrium and the formation of light black holes, the formation and decay of light black holes in the big bang, and the difficulties of the theory. It is emphasized that the existence of mini black holes has not yet been proven

The relationship between a black economic empowerment score ...

African Journals Online (AJOL)

kirstam

company's BEE score/rating and shareholder returns, using an event study methodology and a ... the form of the Broad-Based Black Economic Empowerment Act, no. 53 of 2003 .... asset pricing model). Although more ... portfolios of companies with a specific BEE score, a buy-and-hold or 'style' investment methodology was ...

Black hole gravitohydromagnetics

CERN Document Server

Punsly, Brian

2008-01-01

Black hole gravitohydromagnetics (GHM) is developed from the rudiments to the frontiers of research in this book. GHM describes plasma interactions that combine the effects of gravity and a strong magnetic field, in the vicinity (ergosphere) of a rapidly rotating black hole. This topic was created in response to the astrophysical quest to understand the central engines of radio loud extragalactic radio sources. The theory describes a "torsional tug of war" between rotating ergospheric plasma and the distant asymptotic plasma that extracts the rotational inertia of the black hole. The recoil from the struggle between electromagnetic and gravitational forces near the event horizon is manifested as a powerful pair of magnetized particle beams (jets) that are ejected at nearly the speed of light. These bipolar jets feed large-scale magnetized plasmoids on scales as large as millions of light years (the radio lobes of extragalactic radio sources). This interaction can initiate jets that transport energy fluxes exc...

Few-layer black phosphorus nanoparticles.

Science.gov (United States)

Sofer, Zdenek; Bouša, Daniel; Luxa, Jan; Mazanek, Vlastimil; Pumera, Martin

2016-01-28

Herein, black phosphorus quantum dots and nanoparticles of a few layer thickness were prepared and characterized using STEM, AFM, dynamic light scattering, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and photoluminescence. Impact electrochemistry of the induvidual black phosphorus nanoparticles allows their size determination. The centrifugation of colloidal black phosphorus nanoparticles allowed separation of quantum dots with sizes up to 15 nm. These black phosphorus nanoparticles exhibit a large band gap and are expected to find a wide range of applications from semiconductors to biomolecule tags. The use of black phosphorus nanoparticles for vapour sensing was successfully demonstrated.

Cultivating the Genius of Black Children: Strategies to Close the Achievement Gap in the Early Years

Science.gov (United States)

Sullivan, Debra Ren-Etta

2016-01-01

There has been much attention given to the opportunity gap between white and minority students, especially African American children. Using research and years of experience "Cultivating the Genius of Black Children" is able to break down the cultural influences on learning style and provides a practical approach to helping Black children…

A close nuclear black-hole pair in the spiral galaxy NGC 3393.

Science.gov (United States)

Fabbiano, G; Wang, Junfeng; Elvis, M; Risaliti, G

2011-08-31

The current picture of galaxy evolution advocates co-evolution of galaxies and their nuclear massive black holes, through accretion and galactic merging. Pairs of quasars, each with a massive black hole at the centre of its galaxy, have separations of 6,000 to 300,000 light years (refs 2 and 3; 1 parsec = 3.26 light years) and exemplify the first stages of this gravitational interaction. The final stages of the black-hole merging process, through binary black holes and final collapse into a single black hole with gravitational wave emission, are consistent with the sub-light-year separation inferred from the optical spectra and light-variability of two such quasars. The double active nuclei of a few nearby galaxies with disrupted morphology and intense star formation (such as NGC 6240 with a separation of about 2,600 light years and Mrk 463 with a separation of about 13,000 light years between the nuclei) demonstrate the importance of major mergers of equal-mass spiral galaxies in this evolution; such mergers lead to an elliptical galaxy, as in the case of the double-radio-nucleus elliptical galaxy 0402+379 (with a separation of about 24 light years between the nuclei). Minor mergers of a spiral galaxy with a smaller companion should be a more common occurrence, evolving into spiral galaxies with active massive black-hole pairs, but have hitherto not been seen. Here we report the presence of two active massive black holes, separated by about 490 light years, in the Seyfert galaxy NGC 3393 (50 Mpc, about 160 million light years). The regular spiral morphology and predominantly old circum-nuclear stellar population of this galaxy, and the closeness of the black holes embedded in the bulge, provide a hitherto missing observational point to the study of galaxy/black hole evolution. Comparison of our observations with current theoretical models of mergers suggests that they are the result of minor merger evolution. © 2011 Macmillan Publishers Limited. All rights

Quantifying black carbon light absorption enhancement with a novel statistical approach

Science.gov (United States)

Wu, Cheng; Wu, Dui; Zhen Yu, Jian

2018-01-01

Black carbon (BC) particles in the atmosphere can absorb more light when coated by non-absorbing or weakly absorbing materials during atmospheric aging, due to the lensing effect. In this study, the light absorption enhancement factor, Eabs, was quantified using a 1-year measurement of mass absorption efficiency (MAE) in the Pearl River Delta region (PRD). A new approach for calculating primary MAE (MAEp), the key for Eabs estimation, is demonstrated using the minimum R squared (MRS) method, exploring the inherent source independency between BC and its coating materials. A unique feature of Eabs estimation with the MRS approach is its insensitivity to systematic biases in elemental carbon (EC) and σabs measurements. The annual average Eabs550 is found to be 1.50 ± 0.48 (±1 SD) in the PRD region, exhibiting a clear seasonal pattern with higher values in summer and lower in winter. Elevated Eabs in the summertime is likely associated with aged air masses, predominantly of marine origin, along with long-range transport of biomass-burning-influenced air masses from Southeast Asia. Core-shell Mie simulations along with measured Eabs and absorption Ångström exponent (AAE) constraints suggest that in the PRD, the coating materials are unlikely to be dominated by brown carbon and the coating thickness is higher in the rainy season than in the dry season.

Colours in black and white: the depiction of lightness and brightness in achromatic engravings before the invention of photography.

Science.gov (United States)

Zavagno, Daniele; Massironi, Manfredo

2006-01-01

What is it like to see the world in black and white? In the pioneer days of cinema, when movies displayed grey worlds, was it true that no 'colours' were actually seen? Did every object seen in those projections appear grey in the same way? The answer is obviously no--people in those glorious days were seeing a world full of light, shadows, and objects in which colours were expressed in terms of lightness. But the marvels of grey worlds have not always been so richly displayed. Before the invention of photography, the depiction of scenes in black-and-white had to face some technical and perceptual challenges. We have studied the technical and perceptual constraints that XV-XVIII century engravers had to face in order to translate actual colours into shades of grey. An indeterminacy principle is considered, according to which artists had to prefer the representation of some object or scene features over others (for example brightness over lightness). The reasons for this lay between the kind of grey scale technically available and the kind of information used in the construction of 3-D scenes. With the invention of photography, photomechanical reproductions, and new printing solutions, artists had at their disposal a continuous grey scale that greatly reduces the constraints of the indeterminacy principle.

Alexithymia and personality disorder functioning styles in paranoid schizophrenia.

Science.gov (United States)

Yu, Shaohua; Li, Huichun; Liu, Weibo; Zheng, Leilei; Ma, Ying; Chen, Qiaozhen; Chen, Yiping; Yu, Hualiang; Lu, Yunrong; Pan, Bing; Wang, Wei

2011-01-01

Personality disorder functioning styles might contribute to the inconclusive findings about alexithymic features in schizophrenia. We therefore studied the relationship between alexithymia and personality styles in paranoid schizophrenia. We administered the Chinese versions of the Toronto Alexithymia Scale (TAS-20), the Parker Personality Measure (PERM), the Positive and Negative Syndrome Scale as well as the Hamilton Anxiety and Depression Scales to 60 paranoid schizophrenia patients and 60 healthy control subjects. Patients scored significantly higher on the Positive and Negative Syndrome Scale, TAS 'difficulty identifying feelings' and 'difficulty describing feelings', Hamilton Depression Scale and most PERM scales. In healthy subjects, difficulty identifying feelings predicted the PERM 'dependent' style, and the Hamilton Anxiety Scale predicted difficulty identifying feelings and difficulty describing feelings. In patients, difficulty identifying feelings nonspecifically predicted all the PERM scales; by contrast, the PERM 'antisocial' style predicted difficulty identifying feelings, the 'avoidant' style predicted difficulty describing feelings, and the 'histrionic' and 'paranoid (-)' styles predicted 'externally oriented thinking'. Personality disorder functioning styles - instead of anxiety, depression, psychotic symptoms or disease duration - were specifically associated with alexithymia scales in our patients, which sheds light on a cognitive-personological substrate in paranoid schizophrenia on the one hand, and calls for a longitudinal design to discover how premorbid or postacute residual personality styles contribute to the sluggish disorder on the other. Copyright © 2011 S. Karger AG, Basel.

Source attribution of black carbon in Arctic snow.

Science.gov (United States)

Hegg, Dean A; Warren, Stephen G; Grenfell, Thomas C; Doherty, Sarah J; Larson, Timothy V; Clarke, Antony D

2009-06-01

Snow samples obtained at 36 sites in Alaska, Canada, Greenland, Russia, and the Arctic Ocean in early 2007 were analyzed for light-absorbing aerosol concentration together with a suite of associated chemical species. The light absorption data, interpreted as black carbon concentrations, and other chemical data were input into the EPA PMF 1.1 receptor model to explore the sources for black carbon in the snow. The analysis found four factors or sources: two distinct biomass burning sources, a pollution source, and a marine source. The first three of these were responsible for essentially all of the black carbon, with the two biomass sources (encompassing both open and closed combustion) together accounting for >90% of the black carbon.

Feeding practices and styles used by a diverse sample of low-income parents of preschool-age children.

Science.gov (United States)

Ventura, Alison K; Gromis, Judy C; Lohse, Barbara

2010-01-01

To describe the feeding practices and styles used by a diverse sample of low-income parents of preschool-age children. Thirty- to 60-minute meetings involving a semistructured interview and 2 questionnaires administered by the interviewer. Low-income communities in Philadelphia, PA. Thirty-two parents of 2- to 6-year-old children. The feeding practices and styles of low-income parents of preschoolers. Qualitative interviews analyzed iteratively following a thematic approach; quantitative data analyzed using nonparametric and chi-square tests. Qualitative analyses revealed parents used a myriad of feeding practices to accomplish child-feeding goals. Racial/ethnic differences were seen; East Asian parents used more child-focused decision-making processes, whereas black parents used more parent-focused decision-making processes. Quantitative analyses substantiated racial/ethnic differences; black parents placed significantly higher demands on children for the amounts (H = 5.89, 2 df, P = .05; Kruskal-Wallis) and types (H = 8.39, 2 df, P = .01; Kruskal-Wallis) of food eaten compared to parents of other races/ethnicities. In contrast, significantly higher proportions of East Asian parents were classified as having an indulgent feeding style compared to black parents and parents of other races/ethnicities (chi(2)[4, n = 32] = 9.29, P < .05). Findings provide support for tailoring nutrition education programs to meet the diverse needs of this target audience. Copyright 2010 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

A Primer to Slow Light

OpenAIRE

Leonhardt, U.

2001-01-01

Laboratory-based optical analogs of astronomical objects such as black holes rely on the creation of light with an extremely low or even vanishing group velocity (slow light). These brief notes represent a pedagogical attempt towards elucidating this extraordinary form of light. This paper is a contribution to the book Artificial Black Holes edited by Mario Novello, Matt Visser and Grigori Volovik. The paper is intended as a primer, an introduction to the subject for non-experts, not as a det...

Internal structure of black holes

International Nuclear Information System (INIS)

Cvetic, Mirjam

2013-01-01

Full text: We review recent progress that sheds light on the internal structure of general black holes. We first summarize properties of general multi-charged rotating black holes both in four and five dimensions. We show that the asymptotic boundary conditions of these general asymptotically flat black holes can be modified such that a conformal symmetry emerges. These subtracted geometries preserve the thermodynamic properties of the original black holes and are of the Lifshitz type, thus describing 'a black hole in the asymptotically conical box'. Recent efforts employ solution generating techniques to construct interpolating geometries between the original black hole and their subtracted geometries. Upon lift to one dimension higher, these geometries lift to AdS 3 times a sphere, and thus provide a microscopic interpretation of the black hole entropy in terms of dual two-dimensional conformal field theory. (author)

Measuring spin of black holes in the universe

Indian Academy of Sciences (India)

Table of contents. Measuring spin of black holes in the universe · What is black hole? Accretion Disk and Jet · What is black hole's spin? Accretion Disk · Black Hole's Potential · Light Curves: Photon Count Rate Vs Time · Quasi-Periodic Oscillation · Slide 9 · Model · Slide 11 · Slide 12 · Slide 13 · Summary.

Black Holes Have Simple Feeding Habits

Science.gov (United States)

2008-06-01

The biggest black holes may feed just like the smallest ones, according to data from NASA’s Chandra X-ray Observatory and ground-based telescopes. This discovery supports the implication of Einstein's relativity theory that black holes of all sizes have similar properties, and will be useful for predicting the properties of a conjectured new class of black holes. The conclusion comes from a large observing campaign of the spiral galaxy M81, which is about 12 million light years from Earth. In the center of M81 is a black hole that is about 70 million times more massive than the Sun, and generates energy and radiation as it pulls gas in the central region of the galaxy inwards at high speed. In contrast, so-called stellar mass black holes, which have about 10 times more mass than the Sun, have a different source of food. These smaller black holes acquire new material by pulling gas from an orbiting companion star. Because the bigger and smaller black holes are found in different environments with different sources of material to feed from, a question has remained about whether they feed in the same way. Using these new observations and a detailed theoretical model, a research team compared the properties of M81's black hole with those of stellar mass black holes. The results show that either big or little, black holes indeed appear to eat similarly to each other, and produce a similar distribution of X-rays, optical and radio light. AnimationMulti-wavelength Images of M81 One of the implications of Einstein's theory of General Relativity is that black holes are simple objects and only their masses and spins determine their effect on space-time. The latest research indicates that this simplicity manifests itself in spite of complicated environmental effects. "This confirms that the feeding patterns for black holes of different sizes can be very similar," said Sera Markoff of the Astronomical Institute, University of Amsterdam in the Netherlands, who led the study

Massive black holes and light-element nucleosynthesis in a baryonic universe

Science.gov (United States)

Gnedin, Nickolay Y.; Ostriker, Jeremiah P.; Rees, Martin J.

1995-01-01

We reexamine the model proposed by Gnedin & Ostriker (1992) in which Jeans mass black holes (M(sub BH) approximately = 10(exp 6) solar mass) form shortly after decoupling. There is no nonbaryonic dark matter in this model, but we examine the possibility that Omega(sub b) is considerably larger than given by normal nucleosynthesis. Here we allow for the fact that much of the high baryon-to-photon ratio material will collapse leaving the universe of remaining material with light-element abundances more in accord with the residual baryonic density (approximately = 10(exp -2)) than with Omega(sub 0) and the initial baryonic density (approximately = 10(exp -1)). We find that no reasonable model can be made with random-phase density fluctuations, if the power on scales smaller than 10(exp 6) solar mass is as large as expected. However, phase-correlated models of the type that might occur in connection with topological singularities can be made with Omega(sub b) h(exp 2) = 0.013 +/- 0.001, 0.15 approximately less than Omega(sub 0) approximately less than 0.4, which are either flat (Omega(sub lambda) = 1 - Omega(sub 0)) or open (Omega(sub lambda) = 0) and which satisfy all the observational constraints which we apply, including the large baryon-to-total mass ratio found in the X-ray clusters. The remnant baryon density is thus close to that obtained in the standard picture (Omega(sub b) h(exp 2) = 0.0125 +/- 0.0025; Walker et al. 1991). The spectral index implied for fluctuations in the baryonic isocurvature scenario, -1 less than m less than 0, is in the range expected by other arguments based on large-scale structure and microwave fluctuation constraints. The dark matter in this picture is in the form of massive black holes. Accretion onto them at early epochs releases high-energy photons which significantly heat and reionize the universe. But photodissociation does not materially change light-element abundances. A typical model gives bar-y approximately = 1 x 10(exp -5

Enhanced light absorptivity of black carbon with air pollution development in urban Beijing, China

Science.gov (United States)

Zhang, Y.; Zhang, Q.; Cheng, Y.; Su, H.; He, K.

2017-12-01

The impacts of black carbon (BC) aerosols on air quality and climate are dependent on BC light absorptivity. However, the light absorptivity of ambient BC-containing particles remains conflicting. In this work, we investigated the evolution of BC light absorptivity with pollution development in urban Beijing, China. We found that the mass absorption cross-section (MAC) of ambient BC-containing particles measured during the campaign increased with BC mass concentration, which can be attributed to more coating materials on BC surface with pollution development. A single-particle soot photometer (SP2) measurement showed that the coating thickness (CT) of BC-containing particles increased by 48% with PM1 and BC mass concentration increasing from 10 μg m-3 and 0.3 μg m-3 to 230 μg m-3 and 12 μg m-3. Based on Mie calculation, the CT increase could led to light absorption enhancement (Eab) of BC-containing particles increasing by 22%, consistent with the increase of measured MAC. The relationship between growth rate of BC light absorptivity (kEab) and that of PM1 or rBC concentration (kPM1 or krBC) showed that kEab ≈ 4.8% kPM1 or kEab ≈ 2.5% krBC. The analysis of effective emission intensity (EEI) for BC revealed that the enhancement of BC light absorptivity with increasing pollution levels was dominated by regional transport. During the pollution period, 63% of BC over Beijing originated from regional sources. The aging of these regional BC during atmospheric transport controlled the increase of coating materials for BC-containing particles observed in Beijing. As a result of enhanced light absorptivity with pollution development, BC forcing efficiency could increase by 20% during polluted period. Our work identified the importance of BC on radiative forcing under polluted environment, which is determined by not only the increase of BC mass concentration, but also the enhancement of BC forcing efficiency due to more coating materials.

Induction of single-strand DNA breaks in human cells by H2O2 formed in near-uv (black light)-irradiated medium

International Nuclear Information System (INIS)

Wang, R.J.; Ananthaswamy, H.N.; Nixon, B.T.; Hartman, P.S.; Eisenstark, A.

1980-01-01

When Dulbecco's modified Eagle's medium (depleted of phenol red) was irradiated for up to 3 h by 4 to 5 W/m 2 black light, hydrogen peroxide (H 2 O 2 ) was produced. Generation of H 2 O 2 resulted from riboflavin-sensitized photooxidation of tryptophan and tyrosine. Reagent H 2 O 2 , or hydrogen peroxide generated in black light-exposed aqueous solutions containing riboflavin and tryptophan, induced 2 x 10 4 single-strand breaks per 10 16 daltons of DNA in intact, physiologically viable human D98/AH 2 cells. Concomitant with the single-strand breaks in the cells was loss of cellular reproductive viability. Two classes of photoproducts were identified: H 2 O 2 and non-H 2 O 2 . The H 2 O 2 component of the photoproducts was responsible for all the single-strand break induction but for only partial loss of reproductive viability. The non-H 2 O 2 photoproducts, accountable for the remainder of cell lethality, caused no single-strand breaks

Turbulent black holes.

Science.gov (United States)

Yang, Huan; Zimmerman, Aaron; Lehner, Luis

2015-02-27

We demonstrate that rapidly spinning black holes can display a new type of nonlinear parametric instability-which is triggered above a certain perturbation amplitude threshold-akin to the onset of turbulence, with possibly observable consequences. This instability transfers from higher temporal and azimuthal spatial frequencies to lower frequencies-a phenomenon reminiscent of the inverse cascade displayed by (2+1)-dimensional fluids. Our finding provides evidence for the onset of transitory turbulence in astrophysical black holes and predicts observable signatures in black hole binaries with high spins. Furthermore, it gives a gravitational description of this behavior which, through the fluid-gravity duality, can potentially shed new light on the remarkable phenomena of turbulence in fluids.

Black Self-Esteem and Desegregated Schools.

Science.gov (United States)

Drury, Darrel W.

1980-01-01

Discusses a study to determine attitudes among Black and White students in 194 southern high schools regarding desegregation. Data are presented on differences between schools; test-score achievement; and variations in self-esteem among students in predominantly White, Black, and racially mixed schools. Findings are interpreted in light of…

The Effects of Highlight Color on Immediate Recall on Subjects of Different Cognitive Styles.

Science.gov (United States)

Worley, Gary M.; Moore, David M.

2001-01-01

Discussion of the use of color for enhancing recognition memory focuses on a study of undergraduates that evaluated images as black and white, full color, or highlight color and the effect these characteristics had on recognition memory and recall for learners classified as field-dependent and field-independent in terms of cognitive style. (LRW)

Double-layered liquid crystal light shutter for control of absorption and scattering of the light incident to a transparent display device

Science.gov (United States)

Huh, Jae-Won; Yu, Byeong-Hun; Shin, Dong-Myung; Yoon, Tae-Hoon

2015-03-01

Recently, a transparent display has got much attention as one of the next generation display devices. Especially, active studies on a transparent display using organic light-emitting diodes (OLEDs) are in progress. However, since it is not possible to obtain black color using a transparent OLED, it suffers from poor visibility. This inevitable problem can be solved by using a light shutter. Light shutter technology can be divided into two types; light absorption and scattering. However, a light shutter based on light absorption cannot block the background image perfectly and a light shutter based on light scattering cannot provide black color. In this work we demonstrate a light shutter using two liquid crystal (LC) layers, a light absorption layer and a light scattering layer. To realize a light absorption layer and a light scattering layer, we use the planar state of a dye-doped chiral nematic LC (CNLC) cell and the focal-conic state of a long-pitch CNLC cell, respectively. The proposed light shutter device can block the background image perfectly and show black color. We expect that the proposed light shutter can increase the visibility of a transparent display.

Empowering low-income black families of handicapped children.

Science.gov (United States)

Kalyanpur, M; Rao, S S

1991-10-01

A qualitative study of four black, low-income, single mothers used in-depth interviews and participant observation to evaluate their interactions with outreach agency professionals. Three perceived aspects (disrespect, focus on deficits, and discounting parenting style differences) were associated with exclusionary (unempowering) relationships. A reciprocal and supportive approach was associated with collaborative (empowering) relationships. Implications of these findings for professionals serving minority families are discussed.

Teaching Styles, Learning Styles and the ESP Classroom

Directory of Open Access Journals (Sweden)

Mei Ph’ng Lee

2018-01-01

Full Text Available Learner diversity that exists in the classroom plays a role in influencing the teaching and learning process in the classroom. It should be acknowledged in order for the teaching and learning process to be a meaningful and effective process. Thus, this study examined the learning styles preference of engineering students and the teaching styles preferences of their Technical Communication lecturers. The study also looked at whether the students’ learning styles preferences were influenced by their field of study, gender and ethnic backgrounds. Felder and Solomon’s Index of Learning Styles was administered to 588 engineering students while Grasha and Riechmann-Hruska’s Teaching Style Survey was administered to 10 Technical Communication lecturers. The findings revealed that the students have a marked preference for the visual learning style but balanced preferences for the other learning styles dimensions. The students’ field of study, gender and ethnic backgrounds did not seem to influence the students’ learning styles preferences. As for their Technical Communication lecturers, they seem to favour the student-centered teaching approach. All the data support the notion of adopting a balanced teaching approach in the Technical Communication classroom.

Do Small Canopy Gaps Created by Japanese Black Bears Facilitate Fruiting of Fleshy-Fruited Plants?

Directory of Open Access Journals (Sweden)

Kazuaki Takahashi

Full Text Available Japanese black bears often break branches when climbing trees and feeding on fruit in canopies, thereby creating small canopy gaps. However, the role of black bear-created canopy gaps has not been evaluated in the context of multiple forest dynamics. Our hypothesis was that small canopy gaps created by black bears improve light conditions, which facilitates fruiting of adult fleshy-fruited plants located beneath the gaps, and also that this chain interaction depends on interactions among the size of gaps, improved light conditions, forest layers, and life form of plants. The rPPFD, size of black bear-created canopy gaps, and fruiting/non-fruiting of fleshy-fruited plants were investigated in five forest layers beneath black-bear-created canopy gaps and closed canopies of Mongolian oak (Quercus crispula. We found that light conditions improved beneath black bear-disturbed trees with canopy gaps of large size, and the effect of improvement of light conditions was reduced with descending forest layers. Fruiting of fleshy-fruited plants, especially woody lianas and trees, was facilitated by the improvement of light conditions accompanied by an increase in the size of black-bear-created gaps. Data from this study revealed that canopy disturbance by black bears was key for improving light conditions and accelerating fruiting of fleshy-fruited trees and woody lianas in the canopy layers in particular. Therefore, our hypothesis was mostly supported. Our results provide evidence that Japanese black bears have high potential as ecosystem engineers that increase the availability of resources (light and fruit in this study to other species by causing physical state changes in biotic materials (branches of Q. crispula in this study.

Do Small Canopy Gaps Created by Japanese Black Bears Facilitate Fruiting of Fleshy-Fruited Plants?

Science.gov (United States)

Takahashi, Kazuaki; Takahashi, Kaori; Washitani, Izumi

2015-01-01

Japanese black bears often break branches when climbing trees and feeding on fruit in canopies, thereby creating small canopy gaps. However, the role of black bear-created canopy gaps has not been evaluated in the context of multiple forest dynamics. Our hypothesis was that small canopy gaps created by black bears improve light conditions, which facilitates fruiting of adult fleshy-fruited plants located beneath the gaps, and also that this chain interaction depends on interactions among the size of gaps, improved light conditions, forest layers, and life form of plants. The rPPFD, size of black bear-created canopy gaps, and fruiting/non-fruiting of fleshy-fruited plants were investigated in five forest layers beneath black-bear-created canopy gaps and closed canopies of Mongolian oak (Quercus crispula). We found that light conditions improved beneath black bear-disturbed trees with canopy gaps of large size, and the effect of improvement of light conditions was reduced with descending forest layers. Fruiting of fleshy-fruited plants, especially woody lianas and trees, was facilitated by the improvement of light conditions accompanied by an increase in the size of black-bear-created gaps. Data from this study revealed that canopy disturbance by black bears was key for improving light conditions and accelerating fruiting of fleshy-fruited trees and woody lianas in the canopy layers in particular. Therefore, our hypothesis was mostly supported. Our results provide evidence that Japanese black bears have high potential as ecosystem engineers that increase the availability of resources (light and fruit in this study) to other species by causing physical state changes in biotic materials (branches of Q. crispula in this study).

Black molecular adsorber coatings for spaceflight applications

Science.gov (United States)

Abraham, Nithin S.; Hasegawa, Mark M.; Straka, Sharon A.

2014-09-01

The molecular adsorber coating is a new technology that was developed to mitigate the risk of on-orbit molecular contamination on spaceflight missions. The application of this coating would be ideal near highly sensitive, interior surfaces and instruments that are negatively impacted by outgassed molecules from materials, such as plastics, adhesives, lubricants, epoxies, and other similar compounds. This current, sprayable paint technology is comprised of inorganic white materials made from highly porous zeolite. In addition to good adhesion performance, thermal stability, and adsorptive capability, the molecular adsorber coating offers favorable thermal control characteristics. However, low reflectivity properties, which are typically offered by black thermal control coatings, are desired for some spaceflight applications. For example, black coatings are used on interior surfaces, in particular, on instrument baffles for optical stray light control. Similarly, they are also used within light paths between optical systems, such as telescopes, to absorb light. Recent efforts have been made to transform the white molecular adsorber coating into a black coating with similar adsorptive properties. This result is achieved by optimizing the current formulation with black pigments, while still maintaining its adsorption capability for outgassing control. Different binder to pigment ratios, coating thicknesses, and spray application techniques were explored to develop a black version of the molecular adsorber coating. During the development process, coating performance and adsorption characteristics were studied. The preliminary work performed on black molecular adsorber coatings thus far is very promising. Continued development and testing is necessary for its use on future contamination sensitive spaceflight missions.

Abundance and Night Hourly Dispersal of the Vesicating Beetles of the Genus Paederus (Coleoptera: Staphylinidae) Attracted to Fluorescent, Incandescent, and Black Light Sources in the Brazilian Savanna.

Science.gov (United States)

Lima, D C B; Costa, A A V; Silva, F S

2015-01-01

Paederus beetles are cosmopolitan medically important insects that cause dermatitis linearis to humans. In Brazil, despite the medical importance of these beetles, no studies focusing directly on the abundance and ecological features of harmful species exist. Therefore, this study aims at determining the abundance and the nocturnal hourly dispersal of Paederus species attracted to fluorescent, incandescent, and black light sources in the Brazilian savanna. Paederus species were captured from May to September for three consecutive years, between 2011 and 2013. The specimens were caught hourly, from 1800 to 0600 hours. Paederus beetles were attracted to incandescent, fluorescent, and black light lamps as light sources. A total of 959 individuals of five species were collected. The collected species were Paederus protensus Sharp (59.85%), Paederus columbinus Laporte de Castelnau (29.20%), Paederus mutans Sharp (7.09%), Paederus brasiliensis Erichson (3.34%), and Paederus ferus Erichson (0.52%). The black light was the most attractive source, and the darkest collecting point was the most representative for the number of individuals. The lowest catches were captured at full moon, and the highest catches were between 2200 and 0100 hours. Future investigations are needed to better understand the role of night temperature and soil humidity affecting the seasonal growth of Paederus beetle populations of northeastern Brazil. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The role of iron and black carbon in aerosol light absorption

Directory of Open Access Journals (Sweden)

Y. Derimian

2008-07-01

Full Text Available Iron is a major component of atmospheric aerosols, influencing the light absorption ability of mineral dust, and an important micronutrient that affects oceanic biogeochemistry. The regional distribution of the iron concentration in dust is important for climate studies; however, this is difficult to obtain since it requires in-situ aerosol sampling or simulation of complex natural processes. Simultaneous studies of aerosol chemical composition and radiometric measurements of aerosol optical properties, which were performed in the Negev desert of Israel continuously for about eight years, suggest a potential for deriving a relationship between chemical composition and light absorption properties, in particular the spectral single-scattering albedo.

The two main data sets of the present study were obtained by a sun/sky radiometer and a stacked filter unit sampler that collects particles in coarse and fine size fractions. Analysis of chemical and optical data showed the presence of mixed dust and pollution aerosol in the study area, although their sources appear to be different. Spectral SSA showed an evident response to increased concentrations of iron, black carbon equivalent matter, and their mixing state. A relationship that relates the spectral SSA, the percentage of iron in total particulate mass, and the pollution components was derived. Results calculated, using this relationship, were compared with measurements from dust episodes in several locations around the globe. The comparison showed reasonable agreement between the calculated and the observed iron concentrations, and supported the validity of the suggested approach for the estimation of iron concentrations in mineral dust.

Improvement of Infrared Detectors for Tissue Oximetry using Black Silicon Nanostructures

DEFF Research Database (Denmark)

Petersen, Søren Dahl; Davidsen, Rasmus Schmidt; Alcala, Lucia R.

2014-01-01

We present a nanostructured surface, made of dry etched black silicon, which lowers the reflectance for light incident at all angles. This surface is fabricated on infrared detectors used for tissue oximetry, where the detection of weak diffuse light signals is important. Monte Carlo simulations...... performed on a model of a neonatal head shows that approximately 60% of the injected light will be diffuse reflected. However, the change in diffuse reflected light due to the change in cerebral oxygenation is very low and the light will be completely isotropic scattered. The reflectance of the black...... in quantum efficiency for both normal incident light and light incident at 38°....

Action Identity in Style Simulation Systems: Do Players Consider Machine-Generated Music As of Their Own Style?

Science.gov (United States)

Khatchatourov, Armen; Pachet, François; Rowe, Victoria

2016-01-01

The generation of musical material in a given style has been the subject of many studies with the increased sophistication of artificial intelligence models of musical style. In this paper we address a question of primary importance for artificial intelligence and music psychology: can such systems generate music that users indeed consider as corresponding to their own style? We address this question through an experiment involving both performance and recognition tasks with musically naïve school-age children. We asked 56 children to perform a free-form improvisation from which two kinds of music excerpt were created. One was a mere recording of original performances. The other was created by a software program designed to simulate the participants' style, based on their original performances. Two hours after the performance task, the children completed the recognition task in two conditions, one with the original excerpts and one with machine-generated music. Results indicate that the success rate is practically equivalent in two conditions: children tended to make correct attribution of the excerpts to themselves or to others, whether the music was human-produced or machine-generated (mean accuracy = 0.75 and = 0.71, respectively). We discuss this equivalence in accuracy for machine-generated and human produced music in the light of the literature on memory effects and action identity which addresses the recognition of one's own production. PMID:27199788

Action Identity in Style Simulation Systems: Do Players Consider Machine-Generated Music As of Their Own Style?

Science.gov (United States)

Khatchatourov, Armen; Pachet, François; Rowe, Victoria

2016-01-01

The generation of musical material in a given style has been the subject of many studies with the increased sophistication of artificial intelligence models of musical style. In this paper we address a question of primary importance for artificial intelligence and music psychology: can such systems generate music that users indeed consider as corresponding to their own style? We address this question through an experiment involving both performance and recognition tasks with musically naïve school-age children. We asked 56 children to perform a free-form improvisation from which two kinds of music excerpt were created. One was a mere recording of original performances. The other was created by a software program designed to simulate the participants' style, based on their original performances. Two hours after the performance task, the children completed the recognition task in two conditions, one with the original excerpts and one with machine-generated music. Results indicate that the success rate is practically equivalent in two conditions: children tended to make correct attribution of the excerpts to themselves or to others, whether the music was human-produced or machine-generated (mean accuracy = 0.75 and = 0.71, respectively). We discuss this equivalence in accuracy for machine-generated and human produced music in the light of the literature on memory effects and action identity which addresses the recognition of one's own production.

Style as Supplement - Supplement as Style

DEFF Research Database (Denmark)

Sørensen, Bent

The film Derrida by Amy Ziering Kofman & Kirby Dick (2003) has a memorable scene, showing Derrida watching Derrida watching Derrida. This regression, almost ad infinitum, would seem to have the specific purpose to hammer home the point to the viewer of the film that all communication is mediated......, and to aim for an almost Brechtian Verfremdung-effect, but the film also uses this device as a stylistic trait to characterize something ‘essential' about Derrida and his style. Derrida strikes the same chord by insisting on drawing attention to the artificiality of the making of the film, where questions...... have to be repeated and answers interrupted when the light or the sound is not just right. He furthermore deconstructs the interview process by constantly referring to the impossibility of answering questions without specific contexts, frames and grounds. This makes it easy to characterize the film...

A Linear Algorithm for Black Scholes Economic Model

Directory of Open Access Journals (Sweden)

Dumitru FANACHE

2008-01-01

Full Text Available The pricing of options is a very important problem encountered in financial domain. The famous Black-Scholes model provides explicit closed form solution for the values of certain (European style call and put options. But for many other options, either there are no closed form solution, or if such closed form solutions exist, the formulas exhibiting them are complicated and difficult to evaluate accurately by conventional methods. The aim of this paper is to study the possibility of obtaining the numerical solution for the Black-Scholes equation in parallel, by means of several processors, using the finite difference method. A comparison between the complexity of the parallel algorithm and the serial one is given.

DIM light on Black Hole X-ray Transients

OpenAIRE

Dubus, Guillaume

2005-01-01

The current model for the outburst of stellar-mass black holes X-ray binaries is the disk instability model (DIM). An overview of this model and a discussion of its theoretical and observational challenges are given.

Black Teenage Pregnancy

Directory of Open Access Journals (Sweden)

Loretta I. Winters

2012-01-01

Full Text Available This article examines the relative importance of race and socioeconomic status (SES in determining whether Black and White teenagers report having ever been pregnant. Data gathered from 1999 to 2006 by the National Center for Health Statistics of the Center for Disease Control and Prevention included 1,580 Black and White females aged 15 to 19 years. Results supported the effects of race and SES, with SES having the stronger effect. However, the effects of race and SES differ when controlling for the state of the economy. No difference between Blacks and Whites was found during better economic times. During 2003-2004, the period of greatest economic stress, race was determined to be the only predictor of teenage pregnancy. In particular, during 2005-2006, the reduction in pregnancy rates for Black minors (15-17 fell below those for White minors within their respective SES categories. Policy implications are discussed in light of these findings.

Divergent stress responses and coping styles in psychogenetically selected Roman high-(RHA) and low-(RLA) avoidance rats: behavioural, neuroendocrine and developmental aspects.

Science.gov (United States)

Steimer, Thierry; Driscoll, Peter

2003-06-01

The Swiss sublines of Roman high-(RHA/Verh) and low-(RLA/Verh) avoidance rats have been genetically selected for good vs. poor performance in two-way active avoidance since 1972. RLA/Verh rats show increased stress responses (e.g. freezing behaviour, ACTH, corticosterone and prolactin secretion) and adopt a more passive (or reactive) coping style when confronted with a novel environment. In the open field, elevated plus-maze, black/white box test, and in a new light/dark open field test, RLA/Verh rats appear to be more anxious than their RHA/Verh counterparts. Anxiety may result from their particular psychophysiological profile, i.e. increased emotionality combined with a passive coping style. In contrast, RHA/Verh rats are less responsive to stress, they show little anxiety in novel situations and tend to be impulsive and novelty (sensation) seekers. Some behavioural differences are already noticeable shortly after birth, but the full pattern appears to stabilize only after puberty. Gene-environment interactions are critical in establishing this pattern. The data reviewed indicate that the differences between RHA/Verh and RLA/Verh rats probably result from a complex interaction among divergent anxiety/emotionality characteristics, differences in locomotor activity and novelty/reward seeking, as well as active vs. passive coping styles. It is proposed further that these divergent personality types are to be found not only in other selective breeding programs but in the form of individual differences in most populations of rats used for this type of research.

Ultraviolet safety assessments of insect light traps

OpenAIRE

Sliney, David H.; Gilbert, David W.; Lyon, Terry

2016-01-01

ABSTRACT Near-ultraviolet (UV-A: 315?400?nm), ?black-light,? electric lamps were invented in 1935 and ultraviolet insect light traps (ILTs) were introduced for use in agriculture around that time. Today ILTs are used indoors in several industries and in food-service as well as in outdoor settings. With recent interest in photobiological lamp safety, safety standards are being developed to test for potentially hazardous ultraviolet emissions. A variety of UV ?Black-light? ILTs were measured at...

Quantifying black carbon light absorption enhancement with a novel statistical approach

Directory of Open Access Journals (Sweden)

C. Wu

2018-01-01

Full Text Available Black carbon (BC particles in the atmosphere can absorb more light when coated by non-absorbing or weakly absorbing materials during atmospheric aging, due to the lensing effect. In this study, the light absorption enhancement factor, Eabs, was quantified using a 1-year measurement of mass absorption efficiency (MAE in the Pearl River Delta region (PRD. A new approach for calculating primary MAE (MAEp, the key for Eabs estimation, is demonstrated using the minimum R squared (MRS method, exploring the inherent source independency between BC and its coating materials. A unique feature of Eabs estimation with the MRS approach is its insensitivity to systematic biases in elemental carbon (EC and σabs measurements. The annual average Eabs550 is found to be 1.50 ± 0.48 (±1 SD in the PRD region, exhibiting a clear seasonal pattern with higher values in summer and lower in winter. Elevated Eabs in the summertime is likely associated with aged air masses, predominantly of marine origin, along with long-range transport of biomass-burning-influenced air masses from Southeast Asia. Core–shell Mie simulations along with measured Eabs and absorption Ångström exponent (AAE constraints suggest that in the PRD, the coating materials are unlikely to be dominated by brown carbon and the coating thickness is higher in the rainy season than in the dry season.

Smooth muscle myosin light chain kinase efficiently phosphorylates serine 15 of cardiac myosin regulatory light chain

Energy Technology Data Exchange (ETDEWEB)

Josephson, Matthew P.; Sikkink, Laura A. [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States); Penheiter, Alan R. [Molecular Medicine Program, Mayo Clinic, Rochester, MN 55905 (United States); Burghardt, Thomas P., E-mail: burghardt@mayo.edu [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States); Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905 (United States); Ajtai, Katalin [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States)

2011-12-16

Highlights: Black-Right-Pointing-Pointer Cardiac myosin regulatory light chain (MYL2) is phosphorylated at S15. Black-Right-Pointing-Pointer Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase. Black-Right-Pointing-Pointer It is a widely believed that MYL2 is a poor substrate for smMLCK. Black-Right-Pointing-Pointer In fact, smMLCK efficiently and rapidly phosphorylates S15 in MYL2. Black-Right-Pointing-Pointer Phosphorylation kinetics measured by novel fluorescence method without radioactivity. -- Abstract: Specific phosphorylation of the human ventricular cardiac myosin regulatory light chain (MYL2) modifies the protein at S15. This modification affects MYL2 secondary structure and modulates the Ca{sup 2+} sensitivity of contraction in cardiac tissue. Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase prevalent in uterus and present in other contracting tissues including cardiac muscle. The recombinant 130 kDa (short) smMLCK phosphorylated S15 in MYL2 in vitro. Specific modification of S15 was verified using the direct detection of the phospho group on S15 with mass spectrometry. SmMLCK also specifically phosphorylated myosin regulatory light chain S15 in porcine ventricular myosin and chicken gizzard smooth muscle myosin (S20 in smooth muscle) but failed to phosphorylate the myosin regulatory light chain in rabbit skeletal myosin. Phosphorylation kinetics, measured using a novel fluorescence method eliminating the use of radioactive isotopes, indicates similar Michaelis-Menten V{sub max} and K{sub M} for regulatory light chain S15 phosphorylation rates in MYL2, porcine ventricular myosin, and chicken gizzard myosin. These data demonstrate that smMLCK is a specific and efficient kinase for the in vitro phosphorylation of MYL2, cardiac, and smooth muscle myosin. Whether smMLCK plays a role in cardiac muscle regulation or response to a disease causing stimulus is unclear but it should be considered a potentially significant

Slowly balding black holes

International Nuclear Information System (INIS)

Lyutikov, Maxim; McKinney, Jonathan C.

2011-01-01

The 'no-hair' theorem, a key result in general relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the no-hair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively ''frozen in'' the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes N B =eΦ ∞ /(πc(ℎ/2π)), where Φ ∞ ≅2π 2 B NS R NS 3 /(P NS c) is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. We test this theoretical result via 3-dimensional general relativistic plasma simulations of rotating black holes that start with a neutron star dipole magnetic field with no currents initially present outside the event horizon. The black hole's magnetosphere subsequently relaxes to the split-monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum no-hair theorem.

Configuring Epistemic Authority: The Significance of Film Style in Documentaries about Science.

Science.gov (United States)

Mellor, Felicity

2018-03-01

Argument Among the many limitations of the deficit model of science communication is its inability to account for the qualities of communication products that arise from creative decisions about form and style. This paper examines two documentaries about the nature of time - Patricio Guzmán's Nostalgia for the Light and the first episode of the BBC's Wonders of the Universe series - in order to consider how film style inflects science with different meanings. The analysis pays particular attention to the ways in which authority is assigned between film author, narrator, and depicted subjects and the degree to which different film styles promote epistemological certainty or hesitancy.

Humor Styles and Leadership Styles: Community College Presidents

Science.gov (United States)

Carrica, Jennifer L.

2009-01-01

The purpose of this study was to explore the relationship between leadership styles (transformational, transactional, laissez-faire) and humor styles (affiliative, self-enhancing, aggressive, self-defeating) of community college presidents. Research has shown that humor and leadership styles are related and that humor may enhance interpersonal…

"Having Our Say": High Achieving African American Male College Graduates Speak about Parental Involvement and Parenting Style

Science.gov (United States)

Odom, Lynn Lanier; McNeese, Rose M.

2014-01-01

The purpose of this study was to examine the patterns of parental involvement and parenting styles of the parents of academically successful African American males who graduated from historically Black colleges or universities (Odom, 2013). More specifically, the study investigated relationships among students' perceptions of their parents'…

Style in Music

Science.gov (United States)

Dannenberg, Roger B.

Because music is not objectively descriptive or representational, the subjective qualities of music seem to be most important. Style is one of the most salient qualities of music, and in fact most descriptions of music refer to some aspect of musical style. Style in music can refer to historical periods, composers, performers, sonic texture, emotion, and genre. In recent years, many aspects of music style have been studied from the standpoint of automation: How can musical style be recognized and synthesized? An introduction to musical style describes ways in which style is characterized by composers and music theorists. Examples are then given where musical style is the focal point for computer models of music analysis and music generation.

Black carbon and other light-absorbing impurities in the Andes of Northern Chile

Science.gov (United States)

Rowe, P. M.; Cordero, R.; Warren, S. G.; Pankow, A.; Jorquera, J.; Schrempf, M.; Doherty, S. J.; Cabellero, M.; Carrasco, J. F.; Neshyba, S.

2015-12-01

Black carbon (BC) and other light-absorbing impurities in snow absorb solar radiation and thus have the potential to accelerate glacial retreat and snowmelt. In Chile, glaciers and seasonal snow are important sources of water for irrigation and domestic uses. In July 2015 (Austral winter) we sampled snow in the western Andes in a north-south transect of Chile from 18 S to 34 S. Most of the sampled snow had fallen during a single synoptic event, during 11-13 July. The snow was melted and passed through 0.4 micrometer nuclepore filters. Preliminary estimates indicate that (1) the ratio of BC to dust in snow increases going south from Northern to Central Chile, and (2) in snow sampled during the two weeks following the snowstorm, the impurities were concentrated in the upper 5 cm of snow, indicating that the surface layer became polluted over time by dry deposition.

Conflict resolution styles in the nursing profession.

Science.gov (United States)

Losa Iglesias, Marta Elena; Becerro de Bengoa Vallejo, Ricardo

2012-12-01

in an academic vs. a clinical setting (p = 0.005), with the greatest difference seen for the accommodating style. Of those nurses for whom accommodation was the primary style, 83% worked in a clinical setting compared to just 17% in an academic setting. Further examination of the difference in conflict-solving approaches between academic and clinical nursing environments might shed light on etiologic factors, which in turn might enable nursing management to institute conflict management interventions that are tailored to specific work environments and adapted to different employment levels. This research increases our understanding of preferred approaches to handling conflict in nursing organizations.

Parenting style and practices in stepfamilies

Directory of Open Access Journals (Sweden)

Cassoni C

2012-09-01

Full Text Available Cynthia Cassoni,1 Regina HL Caldana21Graduate School in Psychology, 2Department of Psychology and Education, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP BrazilAbstract: There are several studies on the best way to raise a child, ie, what would be the consequences of our actions for our children. We tend to think of how to educate children in a traditional family, but society has undergone many changes and, hence, family structures have undergone changes too. Today, we find a large number of stepfamilies facing the same issues concerning how to educate a child. Stepfamily configuration often entails more than just the addition of a new parent figure. The objective of this study was to shed some light on how these stepfamilies deal with issues of parenting style and practices. We reviewed the Brazilian and international literature concerning parenting styles and practices in stepfamilies. The papers identified were organized and submitted to analysis. We identified very few papers addressing parenting styles and practices, pointing to an important but unaddressed social change as reflected in new family structures. There is a need for longitudinal studies aimed at understanding not only a particular moment in time, but also moments within a context, ie, an analysis with a holistic approach without preconceived ideas.Keywords: parenting styles, parenting practices, stepfamilies

A black body absorber from vertically aligned single-walled carbon nanotubes

Science.gov (United States)

Mizuno, Kohei; Ishii, Juntaro; Kishida, Hideo; Hayamizu, Yuhei; Yasuda, Satoshi; Futaba, Don N.; Yumura, Motoo; Hata, Kenji

2009-01-01

Among all known materials, we found that a forest of vertically aligned single-walled carbon nanotubes behaves most similarly to a black body, a theoretical material that absorbs all incident light. A requirement for an object to behave as a black body is to perfectly absorb light of all wavelengths. This important feature has not been observed for real materials because materials intrinsically have specific absorption bands because of their structure and composition. We found a material that can absorb light almost perfectly across a very wide spectral range (0.2–200 μm). We attribute this black body behavior to stem from the sparseness and imperfect alignment of the vertical single-walled carbon nanotubes. PMID:19339498

Tidal disruption of asteroids by supermassive black holes

Directory of Open Access Journals (Sweden)

Gomboc A.

2012-12-01

Full Text Available The compact radio source Sgr A* at the centre of our Galaxy harbours a super-massive black hole, and is therefore the nearest laboratory for testing the super-massive black hole astrophysics and environment. Since it is not an active galactic nucleus, it also offers the possibility of observing the capture of low-mass objects, such as comets or asteroids, that may orbit the central black hole. In this paper we discuss conditions for tidal disruption of low-mass objects and predictions of the appearance and light curve of such events, as well as their relevance for the X-ray and infra-red flares detected in Sgr A*. The modelled light curves of such tidal disruption events bear marks of the strong gravitational field: tidal squeezing and elongation of the object, gravitational lensing, aberration of light, and Doppler effects. Finally, we show that this model is able to reproduce and fit X-ray flares.

Coping with Racism: What Works and Doesn't Work for Black Women?

Science.gov (United States)

West, Lindsey M.; Donovan, Roxanne A.; Roemer, Lizabeth

2010-01-01

Perceived racial discrimination (PRD) has deleterious effects on Black Americans. However, there is minimal empirical research on the influence of gender and coping on the relationship between PRD and mental health. This study posited that coping style (i.e., problem-focused coping and avoidant coping) would moderate the relationship between PRD…

Learning Styles.

Science.gov (United States)

Missouri Univ., Columbia. Coll. of Education.

Information is provided regarding major learning styles and other factors important to student learning. Several typically asked questions are presented regarding different learning styles (visual, auditory, tactile and kinesthetic, and multisensory learning), associated considerations, determining individuals' learning styles, and appropriate…

Atmospheric profiles of Black Carbon at remote locations using light-weight airborne Aethalometers

Science.gov (United States)

Hansen, A. D.; Močnik, G.; Drinovec, L.; Lenarcic, M.

2012-12-01

While measurements of atmospheric aerosols are routinely performed at ground-level around the world, there is far less knowledge of their concentrations at altitude: yet this data is a crucial requirement for our understanding of the dispersion of pollutants of anthropogenic origin, with their associated effects on radiative forcing, cloud condensation, and other adverse phenomena. Black Carbon (BC) is a unique tracer for combustion emissions, and can be detected rapidly and with great sensitivity by filter-based optical methods. It has no non-combustion sources and is not transformed by atmospheric processes. Recent technical advances have developed light-weight miniaturized instruments which can be operated on light aircraft or carried aboard commercial passenger flights. From January to April 2012, a single-seat ultra-light aircraft flew around the world on a scientific, photographic and environmental-awareness mission. The flight track crossed all seven continents and all major oceans, with altitudes up to 8.9 km ASL. The aircraft carried a custom-developed high-sensitivity dual-wavelength light-weight Aethalometer, operating at 370 and 880 nm with special provision to compensate for the effects of changing pressure, temperature and humidity. The instrument recorded BC concentrations with high temporal resolution and sensitivity better than 5 ng/m3. We present examples of data from flight tracks over remote oceans, uninhabited land masses, and densely populated areas, analyzing the spectral dependence of absorption to infer the contributions to BC from fossil fuel vs. biomass combustion, and aggregating the data into vertical profiles. The regional and long range transport of BC may be investigated using back-trajectories. We have also operated miniature instruments in the passenger cabins of long-distance commercial aircraft. Since there are no combustion sources within the cabin, any BC in the ventilation air must necessarily have originated from the outside

Physics of Rotating and Expanding Black Hole Universe

Directory of Open Access Journals (Sweden)

Seshavatharam U. V. S.

2010-04-01

Full Text Available Throughout its journey universe follows strong gravity. By unifying general theory of relativity and quantum mechanics a simple derivation is given for rotating black hole’s temperature. It is shown that when the rotation speed approaches light speed temperature approaches Hawking’s black hole temperature. Applying this idea to the cosmic black hole it is noticed that there is “no cosmic temperature” if there is “no cosmic rotation”. Starting from the Planck scale it is assumed that- universe is a rotating and expanding black hole. Another key assumption is that at any time cosmic black hole rotates with light speed. For this cosmic sphere as a whole while in light speed rotation “rate of decrease” in temperature or “rate of increase” in cosmic red shift is a measure of “rate of cosmic expansion”. Since 1992, measured CMBR data indicates that, present CMB is same in all directions equal to 2 : 726 K ; smooth to 1 part in 100,000 and there is no continuous decrease! This directly indicates that, at present rate of decrease in temperature is practically zero and rate of expansion is practically zero. Universe is isotropic and hence static and is rotating as a rigid sphere with light speed. At present galaxies are revolving with speeds proportional to their distances from the cosmic axis of rotation. If present CMBR temperature is 2 : 726 K, present value of obtained angular velocity is 2 : 17 10 Present cosmic mass density and cosmic time are fitted with a ln ( volume ratio parameter. Finally it can be suggested that dark matter and dark energy are ad-hoc and misleading concepts.

Primordial black holes from fifth forces

Science.gov (United States)

Amendola, Luca; Rubio, Javier; Wetterich, Christof

2018-04-01

Primordial black holes can be produced by a long-range attractive fifth force stronger than gravity, mediated by a light scalar field interacting with nonrelativistic "heavy" particles. As soon as the energy fraction of heavy particles reaches a threshold, the fluctuations rapidly become nonlinear. The overdensities collapse into black holes or similar screened objects, without the need for any particular feature in the spectrum of primordial density fluctuations generated during inflation. We discuss whether such primordial black holes can constitute the total dark matter component in the Universe.

Exploring Jets from a Supermassive Black Hole

Science.gov (United States)

Kohler, Susanna

2018-06-01

What are the feeding and burping habits of the supermassive black holes peppering the universe? In a new study, observations of one such monster reveal more about the behavior of its powerful jets.Beams from BehemothsAcross the universe, supermassive black holes of millions to billions of solar masses lie at the centers of galaxies, gobbling up surrounding material. But not all of the gas and dust that spirals in toward a black hole is ultimately swallowed! A large fraction of it can instead be flung out into space again, in the form of enormous, powerful jets that extend for thousands or even millions of light-years in opposite directions.M87, shown in this Hubble image, is a classic example of a nearby (55 million light-years distant) supermassive black hole with a visible, collimated jet. Its counter-jet isnt seen because relativistic effects make the receding jet appear less bright. [The Hubble Heritage Team (STScI/AURA) and NASA/ESA]What causes these outflows to be tightly beamed collimated in the form of jets, rather than sprayed out in all directions? Does the pressure of the ambient medium the surrounding gas and dust that the jet is injected into play an important role? In what regions do these jets accelerate and decelerate? There are many open questions that scientists hope to understand by studying some of the active black holes with jets that live closest to us.Eyes on a Nearby GiantIn a new study led by Satomi Nakahara (The Graduate University for Advanced Studies in Japan), a team of scientists has used multifrequency Very Long Baseline Array (VLBA) and Very Long Array (VLA) images to explore jets emitted from a galaxy just 100 million light-years away: NGC 4261.This galaxys (relatively) close distance as well as the fact that were viewing it largely from the side, so we can clearly see both of its polar jets allows us to observe in detail the structure and intensity of its jets as a function of their distance from the black hole. Nakahara and

The force-free magnetosphere of a rotating black hole

Directory of Open Access Journals (Sweden)

Contopoulos Ioannis

2013-12-01

Full Text Available We explore the analogy with pulsars and investigate the structure of the force-free magnetosphere around a Kerr black hole. We propose that the source of the black hole magnetic field is the Poynting-Robertson effect on the plasma electrons at the inner edge of the surrounding accretion disk, the so called Cosmic Battery. The magnetospheric solution is characterized by the distributions of the magnetic field angular velocity and the poloidal electric current. These are not arbitrary. They are determined self-consistently by requiring that magnetic field lines cross smoothly the two singular surfaces of the problem, the inner ‘light surface’ located inside the ergosphere, and the outer ‘light surface’ which is the generalization of the pulsar light cylinder. The black hole forms a relativistic jet only if it is surrounded by a thick disk and/or extended disk outflows.

Black holes, wormholes and time machines

CERN Document Server

Al-Khalili, Jim

2011-01-01

Bringing the material up to date, Black Holes, Wormholes and Time Machines, Second Edition captures the new ideas and discoveries made in physics since the publication of the best-selling first edition. While retaining the popular format and style of its predecessor, this edition explores the latest developments in high-energy astroparticle physics and Big Bang cosmology.The book continues to make the ideas and theories of modern physics easily understood by anyone, from researchers to students to general science enthusiasts. Taking you on a journey through space and time, author Jim Al-Khalil

Holographic duals of Kaluza-Klein black holes

International Nuclear Information System (INIS)

Azeyanagi, Tatsuo; Ogawa, Noriaki; Terashima, Seiji

2009-01-01

We apply Brown-Henneaux's method to the 5D extremal rotating Kaluza-Klein black holes essentially following the calculation of the Kerr/CFT correspondence, which is not based on supersymmetry nor string theory. We find that there are two completely different Virasoro algebras that can be obtained as the asymptotic symmetry algebras according to appropriate boundary conditions. The microscopic entropies are calculated by using the Cardy formula for both boundary conditions and they perfectly agree with the Bekenstein-Hawking entropy. The rotating Kaluza-Klein black holes contain a 4D dyonic Reissner-Nordstroem black hole and Myers-Perry black hole. Since the D-brane configurations corresponding to these black holes are known, we expect that our analysis will shed some light on deeper understanding of chiral CFT 2 's dual to extremal black holes.

Recurrence network measures for hypothesis testing using surrogate data: Application to black hole light curves

Science.gov (United States)

Jacob, Rinku; Harikrishnan, K. P.; Misra, R.; Ambika, G.

2018-01-01

Recurrence networks and the associated statistical measures have become important tools in the analysis of time series data. In this work, we test how effective the recurrence network measures are in analyzing real world data involving two main types of noise, white noise and colored noise. We use two prominent network measures as discriminating statistic for hypothesis testing using surrogate data for a specific null hypothesis that the data is derived from a linear stochastic process. We show that the characteristic path length is especially efficient as a discriminating measure with the conclusions reasonably accurate even with limited number of data points in the time series. We also highlight an additional advantage of the network approach in identifying the dimensionality of the system underlying the time series through a convergence measure derived from the probability distribution of the local clustering coefficients. As examples of real world data, we use the light curves from a prominent black hole system and show that a combined analysis using three primary network measures can provide vital information regarding the nature of temporal variability of light curves from different spectroscopic classes.

3D-TOFSIMS characterization of black spots in polymer light emitting diodes

International Nuclear Information System (INIS)

Bulle-Lieuwma, C.W.T.; Weijer, P. van de

2006-01-01

The occurrence and formation of black spots areas in PolyLED devices has been studied by time-of-flight SIMS (TOFSIMS). The composition, shape and position of the black spots is visualised by three-dimensional (3D)-TOFSIMS depth-profiling. It has been established that the formation of non-emissive spots is due to the growth of aluminium oxide clusters at the AlBa/polymer interface. Electron injection in the black spots is lost by the resulting local increase of the resistivity of the cathode

Partons and black holes

International Nuclear Information System (INIS)

Susskind, L.; Griffin, P.

1994-01-01

A light-front renormalization group analysis is applied to study matter which falls into massive black holes, and the related problem of matter with transplankian energies. One finds that the rate of matter spreading over the black hole's horizon unexpectedly saturates the causality bound. This is related to the transverse growth behavior of transplankian particles as their longitudinal momentum increases. This growth behavior suggests a natural mechanism to implement 't Hooft's scenario that the universe is an image of data stored on a 2 + 1 dimensional hologram-like projection

A contribution of black and brown carbon to the aerosol light absorption

Science.gov (United States)

Kim, Sang-Woo; Cho, Chaeyoon; Jo, Duseong; Park, Rokjin

2017-04-01

Black carbon (BC) is functionally defined as the absorbing component of atmospheric total carbonaceous aerosols and is typically dominated by soot-like elemental carbon (EC). Organic carbon (OC) has also been shown to absorb strongly at visible to UV wavelengths and the absorbing organics are referred to as brown carbon (BrC; Alexander et al., 2008). These two aerosols contribute to solar radiative forcing through absorption of solar radiation and heating of the absorbing aerosol layer, but most optical instruments that quantify light absorption are unable to distinguish one type of absorbing aerosol from another (Moosmüller et al. 2009). In this study, we separate total aerosol absorption from these two different light absorbers from co-located simultaneous in-situ measurements, such as Continuous Soot Monitoring System (COSMOS), Continuous Light Absorption Photometer (CLAP) and Sunset EC/OC analyzer, at Gosan climate observatory, Korea. We determine the mass absorption cross-section (MAC) of BC, and then estimate the contribution of BC and BrC on aerosol light absorption, together with a global 3-D chemical transport model (GEOS-Chem) simulation. At 565 nm wavelength, BC MAC is found to be about 5.4±2.8 m2 g-1 from COSMOS and Sunset EC/OC analyzer measurements during January-May 2012. This value is similar to those from Alexander et al. (2008; 4.3 ˜ 4.8 m2 g-1 at 550 nm) and Chung et al. (2012; 5.1 m2 g-1 at 520 nm), but slightly lower than Bond and Bergstrom (2006; 7.5±1.2 m2 g-1 at 550 nm). The COMOS BC mass concentration calculated with 5.4 m2 g-1 of BC MAC shows a good agreement with thermal EC concentration, with a good slope (1.1). Aerosol absorption coefficient and BC mass concentration from COSMOS, meanwhile, are approximately 25 ˜ 30 % lower than those of CLAP. This difference can be attributable to the contribution of volatile light-absorbing aerosols (i.e., BrC). The absorption coefficient of BrC, which is determined by the difference of

Black Hole Safari: Tracking Populations and Hunting Big Game

Science.gov (United States)

McConnell, N. J.

2013-10-01

Understanding the physical connection, or lack thereof, between the growth of galaxies and supermassive black holes is a key challenge in extragalactic astronomy. Dynamical studies of nearby galaxies are building a census of black hole masses across a broad range of galaxy types and uncovering statistical correlations between galaxy bulge properties and black hole masses. These local correlations provide a baseline for studying galaxies and black holes at higher redshifts. Recent measurements have probed the extremes of the supermassive black hole population and introduced surprises that challenge simple models of black hole and galaxy co-evolution. Future advances in the quality and quantity of dynamical black hole mass measurements will shed light upon the growth of massive galaxies and black holes in different cosmic environments.

Physics of Rotating and Expanding Black Hole Universe

Directory of Open Access Journals (Sweden)

Seshavatharam U. V. S.

2010-04-01

Full Text Available Throughout its journey universe follows strong gravity. By unifying general theory of relativity and quantum mechanics a simple derivation is given for rotating black hole's temperature. It is shown that when the rotation speed approaches light speed temperature approaches Hawking's black hole temperature. Applying this idea to the cosmic black hole it is noticed that there is "no cosmic temperature" if there is "no cosmic rotation". Starting from the Planck scale it is assumed that universe is a rotating and expanding black hole. Another key assumption is that at any time cosmic black hole rotates with light speed. For this cosmic sphere as a whole while in light speed rotation "rate of decrease" in temperature or "rate of increase" in cosmic red shift is a measure of "rate of cosmic expansion". Since 1992, measured CMBR data indicates that, present CMB is same in all directions equal to $2.726^circ$ K, smooth to 1 part in 100,000 and there is no continuous decrease! This directly indicates that, at present rate of decrease in temperature is practically zero and rate of expansion is practically zero. Universe is isotropic and hence static and is rotating as a rigid sphere with light speed. At present galaxies are revolving with speeds proportional to their distances from the cosmic axis of rotation. If present CMBR temperature is $2.726^circ$ K, present value of obtained angular velocity is $2.17 imes 10^{-18}$ rad/sec $cong$ 67 Km/sec$imes$Mpc. Present cosmic mass density and cosmic time are fitted with a $ln (volume ratio$ parameter. Finally it can be suggested that dark matter and dark energy are ad-hoc and misleading concepts.

Characterization and Comparison of Photocatalytic Activity Silver Ion doped on TiO2(TiO2/Ag+) and Silver Ion doped on Black TiO2(Black TiO2/Ag+)

Science.gov (United States)

Kim, Jin Yi; Sim, Ho Hyung; Song, Sinae; Noh, Yeoung Ah; Lee, Hong Woon; Taik Kim, Hee

2018-03-01

Titanium dioxide (TiO2) is one of the representative ceramic materials containing photocatalyst, optic and antibacterial activity. The hydroxyl radical in TiO2 applies to the intensive oxidizing agent, hence TiO2 is suitable to use photocatalytic materials. Black TiO2was prepared through reduction of amorphous TiO2 conducting under H2 which leads to color changes. Its black color is proven that absorbs 100% light across the whole-visible light, drawing enhancement of photocatalytic property. In this study, we aimed to compare the photocatalytic activity of silver ion doped on TiO2(TiO2/Ag+) and silver ion doped on black TiO2(black TiO2/Ag+) under visible light range. TiO2/Ag+ was fabricated following steps. 1) TiO2 was synthesized by a sol-gel method from Titanium tetraisopropoxide (TTIP). 2) Then AgNO3 was added during an aging process step for silver ion doping on the surface of TiO2. Moreover, Black TiO2/Ag+ was obtained same as TiO2/Ag+ except for calcination under H2. The samples were characterized X-ray diffraction (XRD), UV-visible reflectance (UV-vis DRS), and Methylene Blue degradation test. XRD analysis confirmed morphology of TiO2. The band gap of black TiO2/Ag+ was confirmed (2.6 eV) through UV-vis DRS, which was lower than TiO2/Ag+ (2.9 eV). The photocatalytic effect was conducted by methylene blue degradation test. It demonstrated that black TiO2/Ag+ had a photocatalytic effect under UV light also visible light.

Stationary Black Holes: Uniqueness and Beyond

Directory of Open Access Journals (Sweden)

Heusler Markus

1998-01-01

Full Text Available The spectrum of known black hole solutions to the stationary Einstein equations has increased in an unexpected way during the last decade. In particular, it has turned out that not all black hole equilibrium configurations are characterized by their mass, angular momentum and global charges. Moreover, the high degree of symmetry displayed by vacuum and electro-vacuum black hole space-times ceases to exist in self-gravitating non-linear field theories. This text aims to review some of the recent developments and to discuss them in the light of the uniqueness theorem for the Einstein-Maxwell system.

Stationary Black Holes: Uniqueness and Beyond

Directory of Open Access Journals (Sweden)

Piotr T. Chruściel

2012-05-01

Full Text Available The spectrum of known black-hole solutions to the stationary Einstein equations has been steadily increasing, sometimes in unexpected ways. In particular, it has turned out that not all black-hole-equilibrium configurations are characterized by their mass, angular momentum and global charges. Moreover, the high degree of symmetry displayed by vacuum and electro vacuum black-hole spacetimes ceases to exist in self-gravitating non-linear field theories. This text aims to review some developments in the subject and to discuss them in light of the uniqueness theorem for the Einstein-Maxwell system.

In Situ Analysis of Metabolic Characteristics Reveals the Key Yeast in the Spontaneous and Solid-State Fermentation Process of Chinese Light-Style Liquor

Science.gov (United States)

Kong, Yu; Wu, Qun; Zhang, Yan

2014-01-01

The in situ metabolic characteristics of the yeasts involved in spontaneous fermentation process of Chinese light-style liquor are poorly understood. The covariation between metabolic profiles and yeast communities in Chinese light-style liquor was modeled using the partial least square (PLS) regression method. The diversity of yeast species was evaluated by sequence analysis of the 26S ribosomal DNA (rDNA) D1/D2 domains of cultivable yeasts, and the volatile compounds in fermented grains were analyzed by gas chromatography (GC)-mass spectrometry (MS). Eight yeast species and 58 volatile compounds were identified, respectively. The modulation of 16 of these volatile compounds was associated with variations in the yeast population (goodness of prediction [Q2] > 20%). The results showed that Pichia anomala was responsible for the characteristic aroma of Chinese liquor, through the regulation of several important volatile compounds, such as ethyl lactate, octanoic acid, and ethyl tetradecanoate. Correspondingly, almost all of the compounds associated with P. anomala were detected in a pure culture of this yeast. In contrast to the PLS regression results, however, ethyl lactate and ethyl isobutyrate were not detected in the same pure culture, which indicated that some metabolites could be generated by P. anomala only when it existed in a community with other yeast species. Furthermore, different yeast communities provided different volatile patterns in the fermented grains, which resulted in distinct flavor profiles in the resulting liquors. This study could help identify the key yeast species involved in spontaneous fermentation and provide a deeper understanding of the role of individual yeast species in the community. PMID:24727269

Effect of irradiation with black light fluorescent lamp on coloration and hardness of strawberry [Fragaria ananassa] fruits

International Nuclear Information System (INIS)

Higashio, H.; Hirono, H.; Sato, F.; Tokuda, S.; Uragami, A.

2009-01-01

The effect of irradiation by black light fluorescent lamp on the coloration and hardness of detached strawberry fruits was studied. Only the coloring of fruits (var. Toyonoka) that had started to pigment was accelerated by lamp irradiation. Maintaining the irradiation distance and ambient temperature after treatment was very important to obtain the maximum effect, and the action of lamps was restricted to the irradiated parts. The accelerating effect of a lamp on coloration was observed in all 3 of other varieties examined, and in some varieties, the level of anthocyanin concentration in fruits was greater than that in ripening stage. However, the lamp did not affect the hardness of fruits

Nine optical black-box experiments for lower-secondary students

Science.gov (United States)

Rode, Henning; Friege, Gunnar

2017-05-01

In this paper a sequence of nine, easy to manufacture optical black-box experiments with increasing levels of difficulty, and supportive frameworks for physics classes are introduced. They have been evaluated in a lower-secondary school at the end of optics lessons. A black-box is a kind of experimental task where the inner structure is not visible to the experimenter. Using mirrors, beam-splitters, and blockers in a black-box to manipulate the light beam’s direction through this specific experiment, students are instructed to vary input and observe the output of light to get an idea of the possible inner structure. The presented sequence of black-box experiments requires a basic knowledge of the linear propagation of light and is suitable for beginner physics. Furthermore a framework for concrete implementation to physics classes is given, which covers suitable structure of class, examples for helpful worksheets, and authentic students’ solutions. The difficulty of the specific black-box experiments is given by the students’ success within observing input-output correlation and conclusion of an inner structure. The experiments’ implementation to physics classes may cover elaboration, practice, and aspects of the nature of science even in a beginner’s class. Evaluation has been conducted with students of young age (11-12 years old), however they are suitable for older students also. Although dealing with a time extensive sequence of experiments, students showed a high level of motivation throughout. Overall, implementing this sequence of black-box experiments is seen as valuable and helpful for physics classes.

Grand unification scale primordial black holes: consequences and constraints.

Science.gov (United States)

Anantua, Richard; Easther, Richard; Giblin, John T

2009-09-11

A population of very light primordial black holes which evaporate before nucleosynthesis begins is unconstrained unless the decaying black holes leave stable relics. We show that gravitons Hawking radiated from these black holes would source a substantial stochastic background of high frequency gravititational waves (10(12) Hz or more) in the present Universe. These black holes may lead to a transient period of matter-dominated expansion. In this case the primordial Universe could be temporarily dominated by large clusters of "Hawking stars" and the resulting gravitational wave spectrum is independent of the initial number density of primordial black holes.

The roles of temperature and light in black band disease (BBD) progression on corals of the genus Diploria in Bermuda.

Science.gov (United States)

Kuehl, Kristin; Jones, Ross; Gibbs, David; Richardson, Laurie

2011-03-01

On Bermuda reefs the brain coral Diploria labyrinthiformis is rarely documented with black band disease (BBD), while BBD-affected colonies of Diploria strigosa are common. D. labyrinthiformis on these reefs may be more resistant to BBD or less affected by prevailing environmental conditions that potentially diminish host defenses. To determine whether light and/or temperature influence BBD differently on these two species, infection experiments were conducted under the following experimental treatments: (1) 26 °C, ambient light; (2) 30 °C, ambient light; (3) 30 °C, low light; and (4) 30 °C, high light. A digital photograph of the affected area of each coral was taken each day for 7 days and analyzed with ImageJ image processing software. The final affected area was not significantly different between species in any of the four treatments. BBD lesions were smaller on both species infected under ambient light at 26 °C versus 30 °C. Low light at 30 °C significantly reduced the lesion size on both species when compared to colonies infected at the same temperature under ambient light. Under high light at 30 °C, BBD lesions were larger on colonies of D. strigosa and smaller on colonies of D. labyrinthiformis when compared to colonies infected under ambient light at the same temperature. The responses of both species suggests that BBD progression on both D. strigosa and D. labyrinthiformis is similarly influenced by a combination of light and temperature and that other factors present before infections become established likely contribute to the difference in BBD prevalence in Bermuda. Copyright © 2010 Elsevier Inc. All rights reserved.

Black holes go supersonic

Energy Technology Data Exchange (ETDEWEB)

Leonhardt, Ulf [School of Physics and Astronomy, University of St. Andrews (United Kingdom)

2001-02-01

In modern physics, the unification of gravity and quantum mechanics remains a mystery. Gravity rules the macroscopic world of planets, stars and galaxies, while quantum mechanics governs the micro-cosmos of atoms, light quanta and elementary particles. However, cosmologists believe that these two disparate worlds may meet at the edges of black holes. Now Luis Garay, James Anglin, Ignacio Cirac and Peter Zoller at the University of Innsbruck in Austria have proposed a realistic way to make an artificial 'sonic' black hole in a tabletop experiment (L J Garay et al. 2000 Phys. Rev. Lett. 85 4643). In the February issue of Physics World, Ulf Leonhardt of the School of Physics and Astronomy, University of St. Andrews, UK, explains how the simulated black holes work. (U.K.)

Insomnia symptoms and repressive coping in a sample of older Black and White women

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Pierre-Louis Jessy

2007-01-01

Full Text Available Abstract Background This study examined whether ethnic differences in insomnia symptoms are mediated by differences in repressive coping styles. Methods A total of 1274 women (average age = 59.36 ± 6.53 years participated in the study; 28% were White and 72% were Black. Older women in Brooklyn, NY were recruited using a stratified, cluster-sampling technique. Trained staff conducted face-to-face interviews lasting 1.5 hours acquiring sociodemographic data, health characteristics, and risk factors. A sleep questionnaire was administered and individual repressive coping styles were assessed. Fisher's exact test and Spearman and Pearson analyses were used to analyze the data. Results The rate of insomnia symptoms was greater among White women [74% vs. 46%; χ2 = 87.67, p 1,1272 = 304.75, p s = -0.43, p s = -0.18, p Conclusion Relationships between ethnicity and insomnia symptoms are jointly dependent on the degree of repressive coping, suggesting that Black women may be reporting fewer insomnia symptoms because of a greater ability to route negative emotions from consciousness. It may be that Blacks cope with sleep problems within a positive self-regulatory framework, which allows them to deal more effectively with sleep-interfering psychological processes to stressful life events and to curtail dysfunctional sleep-interpreting processes.

The effect of snow/sea ice type on the response of albedo and light penetration depth (e-folding depth to increasing black carbon

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A. A. Marks

2014-09-01

Full Text Available The optical properties of snow/sea ice vary with age and by the processes they were formed, giving characteristic types of snow and sea ice. The response of albedo and light penetration depth (e-folding depth to increasing mass ratio of black carbon is shown to depend on the snow and sea ice type and the thickness of the snow or sea ice. The response of albedo and e-folding depth of three different types of snow (cold polar snow, wind-packed snow and melting snow and three sea ice (multi-year ice, first-year ice and melting sea ice to increasing mass ratio of black carbon is calculated using a coupled atmosphere–snow/sea ice radiative-transfer model (TUV-snow, over the optical wavelengths of 300–800 nm. The snow and sea ice types are effectively defined by a scattering cross-section, density and asymmetry parameter. The relative change in albedo and e-folding depth of each of the three snow and three sea ice types with increasing mass ratio of black carbon is considered relative to a base case of 1 ng g−1 of black carbon. The relative response of each snow and sea ice type is intercompared to examine how different types of snow and sea ice respond relative to each other. The relative change in albedo of a melting snowpack is a factor of four more responsive to additions of black carbon compared to cold polar snow over a black carbon increase from 1 to 50 ng g−1, while the relative change in albedo of a melting sea ice is a factor of two more responsive to additions of black carbon compared to multi-year ice for the same increase in mass ratio of black carbon. The response of e-folding depth is effectively not dependent on snow/sea ice type. The albedo of sea ice is more responsive to increasing mass ratios of black carbon than snow.

Dark Candles of the Universe: Black Hole Observations

Science.gov (United States)

Aykutalp, Aycin

2016-03-01

In 1916, when Karl Schwarzschild solved the Einstein field equations of general relativity for a spherically symmetric, non-rotating mass no one anticipated the impact black holes would have on astrophysics. I will review the main formation channels for black hole seeds and their evolution through cosmic time. In this, emphasis will be placed on the observational diagnostics of astrophysical black holes and their role on the assembly of galaxy formation and evolution. I then review how these observations put constrain on the seed black hole formation theories. Finally, I present an outlook for how future observations can shed light on our understanding of black holes. This work is supported by NSF Grant AST-1333360.

Comparison of Smoking Habits of Blacks and Whites in a Case-Control Study.

Science.gov (United States)

Kabat, Geoffrey C.; And Others

1991-01-01

Subjects were interviewed to determine smoking habits of 9,252 current cigarette smokers (11 percent black) and 7,555 former smokers (6 percent black). More blacks than whites smoked. Blacks were three times more likely to be light smokers than heavy smokers. Effective prevention may require better understanding of cultural factors affecting…

Starlink Document Styles

Science.gov (United States)

Lawden, M. D.

This document describes the various styles which are recommended for Starlink documents. It also explains how to use the templates which are provided by Starlink to help authors create documents in a standard style. This paper is concerned mainly with conveying the ``look and feel" of the various styles of Starlink document rather than describing the technical details of how to produce them. Other Starlink papers give recommendations for the detailed aspects of document production, design, layout, and typography. The only style that is likely to be used by most Starlink authors is the Standard style.

Transformational Leadership Style as Predictor of Decision Making Styles: Moderating Role of Emotional Intelligence

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Rana Rashid Rehman

2012-12-01

Full Text Available The current study examines the relationship among transformational leadership style and decision making styles. It also determines the moderating role of emotional intelligence in predicting this relationship. Three hypotheses are generated for the study i.e., twohypotheses are to measure the relationship among transformational leadership style and decision making styles whereas third hypothesis is to assess the moderating effect of emotional intelligence. Questionnaire method is used to collect data from 113respondents. Regression analysis is utilized to study the relationship among transformational leadership style and decision making styles and step-wise regression analysis is used to study moderating effect of emotional intelligence. The study foundthat transformational leadership style strongly predicts rational and dependant decision making styles and weakly predict intuitive and spontaneous decision making styles while no association founds with avoidant decision making styles. Present research also foundthat emotional intelligence moderates the relationship among transformational leadership style and decision making styles.

The Weak Gravity Conjecture and the axionic black hole paradox

Science.gov (United States)

Hebecker, Arthur; Soler, Pablo

2017-09-01

In theories with a perturbatively massless 2-form (dual to an axion), a paradox may arise in the process of black hole evaporation. Schwarzschild black holes can support a non-trivial Wilson-line-type field, the integral of the 2-form around their horizon. After such an `axionic black hole' evaporates, the Wilson line must be supported by the corresponding 3-form field strength in the region formerly occupied by the black hole. In the limit of small axion decay-constant f, the energy required for this field configuration is too large. Thus, energy cannot be conserved in the process of black hole evaporation. The natural resolution of this paradox is through the presence of light strings, which allow the black hole to "shed" its axionic hair sufficiently early. This gives rise to a new Weak-Gravity-type argument in the 2-form context: small coupling, in this case f , enforces the presence of light strings or a low cutoff. We also discuss how this argument may be modified in situations where the weak coupling regime is achieved in the low-energy effective theory through an appropriate gauging of a model with a vector field and two 2-forms.

The effects of titanium dioxide coatings on light-derived heating and transdermal heat transfer in bovine skin

Science.gov (United States)

Bartle, S. J.; Thomson, D. U.; Gehring, R.; van der Merwe, D.

2017-11-01

The effects of titanium dioxide coatings of bovine hides on light absorption and transdermal transfer of light-derived heat were investigated. Four hair-on rug hides from Holstein cattle were purchased. Twelve samples about 20 cm on a side were cut from each hide; nine from the black-colored areas, and three from the white areas. Samples were randomized and assigned to four coating treatments: (1) white hide with no coating (White), (2) black hide with no coating (Black), (3) black hide with 50% coating (Mid), and (4) black hide with 100% coating (High). Coatings were applied to the black hide samples using a hand sprayer. Lux measurements were taken using a modified lux meter at three light intensities generated with a broad spectrum, cold halogen light source. Reflectance over a wavelength range of 380 to 900 nm was measured using a spectroradiometer. The transdermal transfer of heat derived from absorbed light was measured by applying a broad spectrum, cold halogen light source to the stratum corneum (coated) side of the sample and recording the temperature of the dermis-side using a thermal camera for 10 min at 30-s intervals. At the high light level, the White, Black, Mid, and High coating treatments had different ( P 400 to 750 nm), Black hides reflected 10 to 15% of the light energy, hides with the Mid coating treatment reflected 35 to 40%, and hides with the High coating treatment reflected 70 to 80% of the light energy. The natural White hide samples reflected 60 to 80% of the light energy. The average maximum temperatures at the dermis-side of the hides due to transferred heat were 34.5, 70.1, 55.0, and 31.7, for the White, Black, Mid, and High treatments, respectively. Reflective coatings containing titanium dioxide on cattle hides were effective in reducing light energy absorption and reduced light-derived heat transfer from the skin surface to deeper skin layers.

The Functional Significance of Black-Pigmented Leaves: Photosynthesis, Photoprotection and Productivity in Ophiopogon planiscapus ‘Nigrescens’

Science.gov (United States)

Hatier, Jean-Hugues B.; Clearwater, Michael J.; Gould, Kevin S.

2013-01-01

Black pigmented leaves are common among horticultural cultivars, yet are extremely rare across natural plant populations. We hypothesised that black pigmentation would disadvantage a plant by reducing photosynthesis and therefore shoot productivity, but that this trait might also confer protective benefits by shielding chloroplasts against photo-oxidative stress. CO2 assimilation, chlorophyll a fluorescence, shoot biomass, and pigment concentrations were compared for near isogenic green- and black-leafed Ophiopogon planiscapus ‘Nigrescens’. The black leaves had lower maximum CO2 assimilation rates, higher light saturation points and higher quantum efficiencies of photosystem II (PSII) than green leaves. Under saturating light, PSII photochemistry was inactivated less and recovered more completely in the black leaves. In full sunlight, green plants branched more abundantly and accumulated shoot biomass quicker than the black plants; in the shade, productivities of the two morphs were comparable. The data indicate a light-screening, photoprotective role of foliar anthocyanins. However, limitations to photosynthetic carbon assimilation are relatively small, insufficient to explain the natural scarcity of black-leafed plants. PMID:23826347

Geometry and dynamics of a tidally deformed black hole

International Nuclear Information System (INIS)

Poisson, Eric; Vlasov, Igor

2010-01-01

The metric of a nonrotating black hole deformed by a tidal interaction is calculated and expressed as an expansion in the strength of the tidal coupling. The expansion parameter is the inverse length scale R -1 , where R is the radius of curvature of the external spacetime in which the black hole moves. The expansion begins at order R -2 , and it is carried out through order R -4 . The metric is parametrized by a number of tidal multipole moments, which specify the black hole's tidal environment. The tidal moments are freely-specifiable functions of time that are related to the Weyl tensor of the external spacetime. At order R -2 the metric involves the tidal quadrupole moments E ab and B ab . At order R -3 it involves the time derivative of the quadrupole moments and the tidal octupole moments E abc and B abc . At order R -4 the metric involves the second time derivative of the quadrupole moments, the first time derivative of the octupole moments, the tidal hexadecapole moments E abcd and B abcd , and bilinear combinations of the quadrupole moments. The metric is presented in a light-cone coordinate system that possesses a clear geometrical meaning: The advanced-time coordinate v is constant on past light cones that converge toward the black hole; the angles θ and φ are constant on the null generators of each light cone; and the radial coordinate r is an affine parameter on each generator, which decreases as the light cones converge toward the black hole. The coordinates are well-behaved on the black-hole horizon, and they are adjusted so that the coordinate description of the horizon is the same as in the Schwarzschild geometry: r=2M+O(R -5 ). At the order of accuracy maintained in this work, the horizon is a stationary null hypersurface foliated by apparent horizons; it is an isolated horizon in the sense of Ashtekar and Krishnan. As an application of our results we examine the induced geometry and dynamics of the horizon, and calculate the rate at which the

Bringing Black Holes Home

Science.gov (United States)

Furmann, John M.

2003-03-01

Black holes are difficult to study because they emit no light. To overcome this obstacle, scientists are trying to recreate a black hole in the laboratory. The article gives an overview of the theories of Einstein and Hawking as they pertain to the construction of the Large Hadron Collider (LHC) near Geneva, Switzerland, scheduled for completion in 2006. The LHC will create two beams of protons traveling in opposing directions that will collide and create a plethora of scattered elementary particles. Protons traveling in opposite directions at very high velocities may create particles that come close enough to each other to feel their compacted higher dimensions and create a mega force of gravity that can create tiny laboratory-sized black holes for fractions of a second. The experiments carried out with LHC will be used to test modern string theory and relativity.

Perceived parenting dimensions and identity styles: exploring the socialization of adolescents' processing of identity-relevant information.

Science.gov (United States)

Smits, Ilse; Soenens, Bart; Luyckx, Koen; Duriez, Bart; Berzonsky, Michael; Goossens, Luc

2008-04-01

This study examined the relationships between crucial dimensions of perceived parenting (support, behavioral control, and psychological control) and the three identity styles defined by Berzonsky [Berzonsky, M. D. (1990). Self-construction over the life span: A process perspective on identity formation. Advances in Personal Construct Psychology, 1, 155-186.]. Each identity style was hypothesized to relate to a specific pattern of perceived parenting dimensions. Hypotheses were examined in a sample of middle and late adolescents (n=674). An information-oriented style was positively predicted by parental support. Contrary to expectations, however, an information-oriented style was also positively predicted by psychological control. A normative identity style was positively predicted by support and behavioral control. In line with expectations, a diffuse-avoidant identity style was positively predicted by psychological control and negatively by maternal (but not paternal) behavioral control. Findings are discussed in light of the literature on the socialization of identity formation and directions for future research are outlined.

ESA's XMM-Newton sees matter speed-racing around a black hole

Science.gov (United States)

2005-01-01

hi-res Size hi-res: 715 Kb Credits: NASA/Dana Berry, SkyWorks Digital ESA’s XMM-Newton sees matter speed-racing around a black hole Click here for animation in MOV format Movie still in TIFF format (9761 Kb) Movie still in JPG format (715 Kb) This animation depicts three hot chunks of matter orbiting a black hole. If placed in our Solar System, this black hole would appear like a dark abyss spread out nearly as wide as Mercury's orbit. And the three chunks (each as large as the Sun) would be as far out as Jupiter. They orbit the black hole in a lightning-quick 30 000 kilometres per second, over a tenth of the speed of light. hi-res Size hi-res: 220 Kb Credits: NASA/Dana Berry, SkyWorks Digital ESA’s XMM-Newton sees matter speed-racing around a black hole Click here for animation in MPG format Movie still in TIFF format (2553 Kb) Movie still in JPG format (220 Kb) This is a simplified illustration of two hot chunks of matter orbiting a black hole, showing how scientists tracked the blobs by observing their Doppler shift. First, we see one blob. Note how the energy emitted from this orbiting material rises to about 6.5 kilo-electron volt (an energy unit) as it moves towards us, and then falls to about 5.8 kilo-electron volt as it moves away. This is the 'Doppler effect' and a similar phenomenon happens with the changing pitch of a police siren. If it is approaching, the frequency of the sound is higher, but if it is receding the frequency is lower. Matter goes round and round; energy goes up and down. About 14 seconds into the animation, a second blob is added, which also displays a rise and fall in energy during its orbit. The observation, made with ESA’s XMM-Newton observatory, marks the first time scientists could trace individual blobs of shredded matter on a complete journey around a black hole. This provides a crucial measurement that has long been missing from black hole studies: an orbital period. Knowing this, scientists can measure black hole mass and

VIOLENT BLACK MAN AND THE MYTH OF BLACK MACHO IN EUGENE O’NEILL’S "THE DREAMY KID"

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Agnieszka Łobodziec

2014-10-01

Full Text Available The aim of this article is the investigation of the extent to which Eugene O’Neill, in his drama "The Dreamy Kid", (reconstructs, or employs, the black macho myth, which negatively images black men as marginalized and violent. This undertaking questions O’Neill’s self-proclaimed progressive racial attitudes and stated focus on the universal nature of human existence, which he professed to express through drama. Moreover, the article challenges the mainstream view of "The Dreamy Kid" as progressive. Although the play focalizes the experience of a marginalized black man, which could be interpreted as the playwright’s concern with the unjust racial and class stratification of American society, O’Neill’s production, unfortunately, contains a number of pervasive stereotypes relative to black people’s alleged moral degeneracy, primitiveness, and violent behavior, which threatens the white dominated constructed order. In terms of gendered racial politics, in the article attention is given to O’Neill’s presentation of black male negotiations with the white patriarchal power structure, embodied by the police forces, and with black matriarchy, represented by O’Neill’s stereotypical character portrayal of a dominant elderly black woman. Lastly, an overall analysis is performed in light of the call for an autonomous black art, which emerged among black artists in opposition to the demeaning, unrealistic, stereotypical portrayals of black victims of oppression by white American writers.

Variation in Physician Practice Styles within and across Emergency Departments.

Directory of Open Access Journals (Sweden)

Jessica Van Parys

Full Text Available Despite the significant responsibility that physicians have in healthcare delivery, we know surprisingly little about why physician practice styles vary within or across institutions. Estimating variation in physician practice styles is complicated by the fact that patients are rarely randomly assigned to physicians. This paper uses the quasi-random assignment of patients to physicians in emergency departments (EDs to show how physicians vary in their treatment of patients with minor injuries. The results reveal a considerable degree of variation in practice styles within EDs; physicians at the 75th percentile of the spending distribution spend 20% more than physicians at the 25th percentile. Observable physician characteristics do not explain much of the variation across physicians, but there is a significant degree of sorting between physicians and EDs over time, with high-cost physicians sorting into high-cost EDs as they gain experience. The results may shed light on why some EDs remain persistently higher-cost than others.

Stability of the Light Output, Oral Cavity Tip Accessibility in Posterior Region and Emission Spectrum of Light-Curing Units.

Science.gov (United States)

André, C B; Nima, G; Sebold, M; Giannini, M; Price, R B

2018-04-09

This study evaluated the light output from six light-emitting diode dental curing lights after 25 consecutive light exposures without recharging the battery, tip accessibility in the posterior region, and light beam spread from light-curing units. Irradiance, spectral peak, and radiant exposure were measured with the battery fully charged (Bluephase Style, ESPE Cordless, Elipar S10, Demi Ultra, Valo Cordless, and Radii-Cal) and monitored for 25 light exposures (each lasting 10 seconds). The tip diameter was measured to identify the beam size and the ability of the six light-curing units to irradiate all areas of the lower second molar in the standard output setting. Four curing lights delivered a single peak wavelength from 454 to 462 nm, and two (Bluephase Style and Valo Cordless) delivered multiple emission peaks (at 410 and 458 nm and 400, 450, and 460 nm, respectively). The irradiance and radiant exposure always decreased after 25 exposures by 2% to 8%, depending on the light unit; however, only ESPE Cordless, Valo Cordless, and Radii-Cal presented a statistical difference between the first and the last exposure. The tip diameter ranged from 6.77 mm to 9.40 mm. The Radii-Cal delivered the lowest radiant exposure and irradiance. This light was also unable to access all the teeth with the tip parallel to the occlusal surface of the tooth. Not all of the blue-emitting lights deliver the same emission spectra, and some curing lights delivered a lower irradiance (as much as 8% lower) after the 25th exposure.

Magnetohydrodynamic Simulations of Black Hole Accretion

Science.gov (United States)

Avara, Mark J.

Black holes embody one of the few, simple, solutions to the Einstein field equations that describe our modern understanding of gravitation. In isolation they are small, dark, and elusive. However, when a gas cloud or star wanders too close, they light up our universe in a way no other cosmic object can. The processes of magnetohydrodynamics which describe the accretion inflow and outflows of plasma around black holes are highly coupled and nonlinear and so require numerical experiments for elucidation. These processes are at the heart of astrophysics since black holes, once they somehow reach super-massive status, influence the evolution of the largest structures in the universe. It has been my goal, with the body of work comprising this thesis, to explore the ways in which the influence of black holes on their surroundings differs from the predictions of standard accretion models. I have especially focused on how magnetization of the greater black hole environment can impact accretion systems.

Lighting in the urban context case study: Exterior decorative lighting of St. Marko's Church in Belgrade

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Đokić Lidija

2006-01-01

Full Text Available In the past few years more attention has been devoted to exterior decorative lighting in Belgrade. Unfortunately, illuminance is very often the only quality factor for lighting design. Lighting quality is a broader concept than illuminance (quantity of light, determined by a number of factors out of which some can and others cannot be quantitatively determined. Buildings and spaces with urban, architectural and/or style values impose certain requests for lighting design, which can either emphasize or degrade these values. The lighting designer has the obligation to respond to the imposed requests and in this way support the building concept, as well as its role in the urban context. Various possibilities of artificial lighting enable better, more effective and more interesting impressions of buildings than experienced in daylight conditions. Some of the significant possibilities of artificial lighting, which can satisfy requests imposed by urban architectural or style elements, include: The possibility to emphasize elements of style, building details or ornaments, which resemble the most important values on a building or façade. This enables elements of exceptional value to be clearly noticeable (in a greater extent than in daylight conditions; Decorative lighting allows the possibility of presenting the hierarchy of architectural or style elements, which is a contribution to the emphasis of the main idea and building spirit; ® The possibility to emphasize proportions and/or balance of the façade, making solids and voids clearly distinctive; If emphasis of the building concept is the lighting aim, it is possible to realize different impressions from the ones experienced in daylighting (lighting the facade plane which is drawn in and remains in the shadow during the day; When lighting modern architecture, decorative lighting has the possibility to promote the main idea, emphasizing proportions, valuable building parts and/or the rhythm of the

Style over substance: What can parenting styles tell us about ownership styles and obesity in companion animals?

Science.gov (United States)

German, Alexander J

2015-01-01

Obesity is a major medical concern in human subjects, and most concerning is the rapid recent increase in childhood obesity. Children are more likely to be obese if their parents are obese, an effect that is mediated both by genetics and environment, most notably parental influence. Four major parenting styles have been recognised: authoritative; authoritarian; indulgent; uninvolved. Too much parental control, as with the authoritarian style, is associated with a higher weight status in children. Conversely, indulgent feeding styles can also have negative consequences and, where control is too lax, a poor relationship with food develops, which may also lead to weight gain. Obesity is also a growing concern in companion animals, and it has parallels with obesity in children. For instance, overweight people are more likely to own overweight dogs. Furthermore, the care that people provide for their pets mirrors that which parents provide for children, and pets are commonly viewed as child substitutes. These similarities raise obvious questions about whether different styles of pet ownership exist, and what part they may play in attitudes to feeding as well as predisposition to obesity in pets. Future work could focus on determining to what extent styles of pet ownership mirror parenting styles, whether there are links to obesity in dogs and cats. Knowledge regarding the owner-pet bond might provide comparative insights into the links between parenting styles and childhood obesity.

Quantum capacity of quantum black holes

Science.gov (United States)

Adami, Chris; Bradler, Kamil

2014-03-01

The fate of quantum entanglement interacting with a black hole has been an enduring mystery, not the least because standard curved space field theory does not address the interaction of black holes with matter. We discuss an effective Hamiltonian of matter interacting with a black hole that has a precise analogue in quantum optics and correctly reproduces both spontaneous and stimulated Hawking radiation with grey-body factors. We calculate the quantum capacity of this channel in the limit of perfect absorption, as well as in the limit of a perfectly reflecting black hole (a white hole). We find that the white hole is an optimal quantum cloner, and is isomorphic to the Unruh channel with positive quantum capacity. The complementary channel (across the horizon) is entanglement-breaking with zero capacity, avoiding a violation of the quantum no-cloning theorem. The black hole channel on the contrary has vanishing capacity, while its complement has positive capacity instead. Thus, quantum states can be reconstructed faithfully behind the black hole horizon, but not outside. This work sheds new light on black hole complementarity because it shows that black holes can both reflect and absorb quantum states without violating the no-cloning theorem, and makes quantum firewalls obsolete.

Fruit quality in strawberry (Fragaria sp. grown on colored plastic mulch

Directory of Open Access Journals (Sweden)

Casierra-Posada Fánor

2011-12-01

Full Text Available

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Assessing learning styles of Saudi dental students using Kolb's Learning Style Inventory.

Science.gov (United States)

ALQahtani, Dalal A; Al-Gahtani, Sara M

2014-06-01

Experiential learning theory (ELT), a theory developed by David Kolb that considers experience to be very important for learning, classifies learners into four categories: Divergers, Assimilators, Convergers, and Accommodators. Kolb used his Learning Style Inventory (LSI) to validate ELT. Knowing the learning styles of students facilitates their understanding of themselves and thereby increases teaching efficiency. Few studies have been conducted that investigate learning preferences of students in the field of dentistry. This study was designed to distinguish learning styles among Saudi dental students and interns utilizing Kolb's LSI. The survey had a response rate of 62 percent (424 of 685 dental students), but surveys with incomplete answers or errors were excluded, resulting in 291 usable surveys (42 percent of the student population). The independent variables of this study were gender, clinical experience level, academic achievement as measured by grade point average (GPA), and specialty interest. The Diverging learning style was the dominant style among those in the sample. While the students preferred the Assimilating style during their early preclinical years, they preferred the Diverging style during their later clinical years. No associations were found between students' learning style and their gender, GPA, or specialty interest. Further research is needed to support these findings and demonstrate the impact of learning styles on dental students' learning.

Black holes in Lorentz-violating gravity theories

International Nuclear Information System (INIS)

Barausse, Enrico; Sotiriou, Thomas P

2013-01-01

Lorentz symmetry and the notion of light cones play a central role in the definition of horizons and the existence of black holes. Current observations provide strong indications that astrophysical black holes do exist in Nature. Here we explore what happens to the notion of a black hole in gravity theories where local Lorentz symmetry is violated, and discuss the relevant astrophysical implications. Einstein-aether theory and Hořava gravity are used as the theoretical background for addressing this question. We review earlier results about static, spherically symmetric black holes, which demonstrate that in Lorentz-violating theories there can be a new type of horizon and, hence, a new notion of black hole. We also present both known and new results on slowly rotating black holes in these theories, which provide insights on how generic these new horizons are. Finally, we discuss the differences between black holes in Lorentz-violating theories and in General Relativity, and assess to what extent they can be probed with present and future observations. (paper)

Intergenerational Transmission of Family Factors: Parenting Styles, Attachment Styles & Family Climate

Directory of Open Access Journals (Sweden)

میرمحمدباقر آزادموسوی

2015-12-01

Full Text Available This research aimed to examine the relationship between parental styles (authoritative, permissive, authoritarian and neglectful, attachment styles (secure, avoidant and ambivalent & family climate (hot and cold of two generations. Subjects were 220 (110 boy students of third class of secondary schools of two districts of Qazvin, and 110 parents who were selected via cluster sampling. In this study, Schaffer,s parenting questionnaires styles (Naqashian, 1358 and Collins and Read,s attachment (Collins & Read, 1990 were used as measures for collecting required data. Analyzes were carried out using simple linear regression, pearson correlation and chi-square. Results revealed that parenting styles, attachment styles and family climate of parents, predict same variables in children as second generation.

New view about black holes. [Tachyon--bradyon transformation at horizon

Energy Technology Data Exchange (ETDEWEB)

De Sabbata, V; Pavsic, M; Recami, E

1977-01-01

For a Schwarzschild black-hole, as reference frame is chosen the frame sigma at rest with respect to the Schwarzschild metric. In this locally non-inertial frame, a freely falling body is shown to reach the speed of light on the horizon and then to travel faster than light inside the horizon. The usual Szekeres--Kruskal (SK) coordinates represent themselves frames that (with respect to the frames sigma) travel at subluminal speed outside, at luminal speed on, and at superluminal speed inside the horizon (so that SK frames always describe any free falling body as a standard, slower-than-light object). Finally, black-holes are shown to be possible sources of tachyons.

Cytotoxic, mutagenic and carcinogenic properties of ultraviolet radiation : shining light on photolesions

NARCIS (Netherlands)

J. Jans (Judith)

2003-01-01

textabstractExposure to ultraviolet light (UV light) poses a serieus threat to human health. An altered life style (holidays in the sun, tanning devices) has led to increased exposure to UV light in the Western population. UV light damages the DNA, the carrier of genetic information, which can

The Relationship between Parenting Styles and Adult Attachment Styles from Jordan University Students

OpenAIRE

Ahmad M. Mahasneh; Zohair H. Al-Zoubi; Omar T. Batayenh; Mohammad S. Jawarneh

2013-01-01

The purpose of this study was to examine the relationship between parenting styles and adult attachment styles. A random sample of (564) male and female students at the faculty of educational sciences was chosen selected. Two questionnaires on attachment styles and parenting styles were administered to the selected sample population during the academic year of 2012-2013. Results indicated significant positive correlations between the authoritative, negligent and authoritarian parenting styles...

Measuring the $W$-hair of String Black Holes

CERN Document Server

Ellis, Jonathan Richard; Nanopoulos, Dimitri V; Ellis, John

1992-01-01

We have argued previously that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers ($W$-hair) which characterise black hole states and maintain quantum coherence. Here we study ways of measuring the $W$-hair of spherically-symmetric four-dimensional objects with event horizons, treated as effectively two-dimensional string black holes. Measurements can be done either through the s-wave scattering of light particles off the string black-hole background, or through interference experiments of Aharonov-Bohm type. In the first type of measurement, selection rules

VLBA Reveals Closest Pair of Supermassive Black Holes

Science.gov (United States)

2006-05-01

Astronomers using the National Science Foundation's Very Long Baseline Array (VLBA) radio telescope have found the closest pair of supermassive black holes ever discovered in the Universe -- a duo of monsters that together are more than 150 million times more massive than the Sun and closer together than the Earth and the bright star Vega. The VLBA The VLBA CREDIT: NRAO/AUI/NSF "These two giant black holes are only about 24 light-years apart, and that's more than 100 times closer than any pair found before," said Cristina Rodriguez, of the University of New Mexico (UNM) and Simon Bolivar University in Venezuela. Black holes are concentrations of mass with gravity so strong that not even light can escape them. The black hole pair is in the center of a galaxy called 0402+379, some 750 million light-years from Earth. Astronomers presume that each of the supermassive black holes was once at the core of a separate galaxy, then the two galaxies collided, leaving the black holes orbiting each other. The black holes orbit each other about once every 150,000 years, the scientists say. "If two black holes like these were to collide, that event would create the type of strong gravitational waves that physicists hope to detect with instruments now under construction," said Gregory Taylor, of UNM. The physicists will need to wait, though: the astronomers calculate that the black holes in 0402+379 won't collide for about a billion billion years. "There are some things that might speed that up a little bit," Taylor remarked. An earlier VLBA study of 0402+379, an elliptical galaxy, showed the pair of radio-wave-emitting objects near its core. Further studies using the VLBA and the Hobby-Eberly Telescope in Texas, revealed that the pair of objects is indeed a pair of supermassive black holes. "We needed the ultra-sharp radio 'vision' of the VLBA, particularly at the high radio frequencies of 22 and 43 GigaHertz, to get the detail needed to show that those objects are a pair of

Au Nanoclusters Sensitized Black TiO2-x Nanotubes for Enhanced Photodynamic Therapy Driven by Near-Infrared Light.

Science.gov (United States)

Yang, Dan; Gulzar, Arif; Yang, Guixin; Gai, Shili; He, Fei; Dai, Yunlu; Zhong, Chongna; Yang, Piaoping

2017-12-01

The low reactive oxygen species production capability and the shallow tissue penetration of excited light (UV) are still two barriers in photodynamic therapy (PDT). Here, Au cluster anchored black anatase TiO 2- x nanotubes (abbreviated as Au 25 /B-TiO 2- x NTs) are synthesized by gaseous reduction of anatase TiO 2 NTs and subsequent deposition of noble metal. The Au 25 /B-TiO 2- x NTs with thickness of about 2 nm exhibit excellent PDT performance. The reduction process increased the density of Ti 3+ on the surface of TiO 2 , which effectively depresses the recombination of electron and hole. Furthermore, after modification of Au 25 nanoclusters, the PDT efficiency is further enhanced owing to the changed electrical distribution in the composite, which forms a shallow potential well on the metal-TiO 2 interface to further hamper the recombination of electron and hole. Especially, the reduction of anatase TiO 2 can expend the light response range (UV) of TiO 2 to the visible and even near infrared (NIR) light region with high tissue penetration depth. When excited by NIR light, the nanoplatform shows markedly improved therapeutic efficacy attributed to the photocatalytic synergistic effect, and promotes separation or restrained recombination of electron and hole, which is verified by experimental results in vitro and in vivo. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

ESA's high-energy observatories spot doughnut-shaped cloud with a black-hole filling

Science.gov (United States)

2004-07-01

hi-res Size hi-res: 7265 KB Credits: ESA, V. Beckmann (GSFC) Doughnut-shaped cloud surrounds black hole This artist's impression shows the thick dust torus that astronomers believe surrounds supermassive black holes and their accretion discs, like the one harboured in the nucleus of the spiral galaxy NGC 4388. When the torus is seen `edge-on’ as in this case, the visible light emitted by the accretion disc is partially blocked. However, the sharp X-ray and gamma-ray eyes of XMM-Newton and Integral can peer through the thick dust and see how the energy released by the accretion disc interacts with and is absorbed by the torus. Black holes are objects so compact and with gravity so strong that not even light can escape from them. Scientists think that `supermassive’ black holes are located in the cores of most galaxies, including our Milky Way galaxy. They can contain the mass of thousands of millions of suns, confined within a region no larger than our Solar System. They appear to be surrounded by a hot, thin disk of accreting gas and, farther out, the thick doughnut-shaped torus. Depending on the inclination of the torus, it can hide the black hole and the hot accretion disc from the line of sight. Galaxies in which a torus blocks the light from the central accretion disc are called `Seyfert 2’ types and are usually faint to optical telescopes. Another theory, however, is that these galaxies appear rather faint because the central black hole is not actively accreting gas and the disc surrounding it is therefore faint. An international team of astronomers led by Dr Volker Beckmann, Goddard Space Flight Center (Greenbelt, USA) has studied one of the nearest objects of this type, a spiral galaxy called NGC 4388, located 65 million light years away in the constellation Virgo. Since NGC 4388 is relatively close, and therefore unusually bright for its class, it is easier to study. Astronomers often study black holes that are aligned face-on, thus avoiding the

Styles and Style-Stretching: How are They Related to Successful Learning?

Science.gov (United States)

Griffiths, Carol; İnceçay, Görsev

2016-06-01

Although the learning style construct has aroused much interest over the years, questions remain regarding basic issues such as definition, the validity and/or reliability of various measurement instruments, and the relationship between learning style and successful learning. Furthermore, although maintaining stylistic flexibility is recommended by many authors, few studies have attempted to relate the style-stretching concept to successful learning. This study therefore attempted to address these questions. According to results, conducted among 106 Turkish university students, using an original instrument constructed using elements from established questionnaires, a small group of styles was significantly correlated with exam results, accounting for about a quarter of the variance (considered a large effect size in social science). In addition, higher-scoring students reported a more eclectic range of styles, suggesting more willingness to style-stretch, while lower-scoring students reported a more limited range. Pedagogical implications as well as areas for ongoing research are suggested.

Simulating autonomous driving styles: Accelerations for three road profiles

Directory of Open Access Journals (Sweden)

Karjanto Juffrizal

2017-01-01

Full Text Available This paper presents a new experimental approach to simulate projected autonomous driving styles based on the accelerations at three road profiles. This study was focused on the determination of ranges of accelerations in triaxial direction to simulate the autonomous driving experience. A special device, known as the Automatic Acceleration and Data controller (AUTOAccD, has been developed to guide the designated driver to accomplish the selected accelerations based on the road profiles and the intended driving styles namely assertive, defensive and light rail transit (LRT. Experimental investigations have been carried out at three different road profiles (junction, speed hump, and corner with two designated drivers with five trials on each condition. A driving style with the accelerations of LRT has also been included in this study as it is significant to the present methodology because the autonomous car is predicted to accelerate like an LRT, in such a way that it enables the users to conduct activities such as working on a laptop, using personal devices or eating and drinking while travelling. The results demonstrated that 92 out of 110 trials of the intended accelerations for autonomous driving styles could be achieved and simulated on the real road by the designated drivers. The differences between the two designated drivers were negligible, and the rates of succeeding in realizing the intended accelerations were high. The present approach in simulating autonomous driving styles focusing on accelerations can be used as a tool for experimental setup involving autonomous driving experience and acceptance.

The Relationship between Decision Making Styles and Leadership Styles among Public Schools Principals

Science.gov (United States)

Al-Omari, Aieman Ahmad

2013-01-01

The present study examined the relationships between leadership styles and decision-making styles among public schools principals. A total of 108 principals returned questionnaires from Russaifa Education District in Jordan. The Decision Style Inventory and the Administrative Styles Questionnaire were used in this study. "Directive decision…

NuSTAR observations of the black holes GS 1354-645: Evidence of rapid black hole spin

DEFF Research Database (Denmark)

El-Batal, A. M.; Miller, J. M.; Reynolds, M. T.

2016-01-01

We present the results of a NuSTAR study of the dynamically confirmed stellar-mass black hole GS 1354-645. The source was observed during its 2015 "hard" state outburst; we concentrate on spectra from two relatively bright phases. In the higher-flux observation, the broadband NuSTAR spectra reveal...... a clear, strong disk reflection spectrum, blurred by a degree that requires a black hole spin of a = cf/GM(2) >= 0.98 (1 sigma statistical limits only). The fits also require a high inclination: 0 similar or equal to 75 (2)degrees. Strong "dips" are sometimes observed in the X-ray light curves of sources...... in stellar-mass black holes, and inner accretion flow geometries at moderate accretion rates....

The Relationships of Problem Solving Styles to Parenting Styles: Two Studies

Science.gov (United States)

Neyen, Julia; Volpe, Carolyn Ann; Selby, Edwin C.; Houtz, John C.

2017-01-01

Two independent studies were conducted to examine the relationship of problem solving styles to parenting styles. Both studies used VIEW: An Assessment of Problem Solving Style and the Parental Authority Questionnaire (PAQ). Study 1 included 173 adults recruited using Mechanical Turk and Study 2 included 131 adults recruited using Qualtrics. Data…

Light absorption and scattering by aggregates: Application to black carbon and snow grains

International Nuclear Information System (INIS)

Liou, K.N.; Takano, Y.; Yang, P.

2011-01-01

under the condition of equal geometrical cross section area for both external and internal mixing states; however, nonspherical snowflakes scatter less light in forward directions than spheres, resulting in a substantial reduction of the asymmetry factor. We further demonstrate that small soot particles on the order of 1 μm internally mixed with snow grains could effectively reduce snow albedo by as much as 5-10%. Indeed, the depositions of black carbon would substantially reduce mountain-snow albedo, which would lead to surface warming and snowmelt, critical to regional climatic surface temperature amplification and feedback.

Quantum chaos and the black hole horizon

CERN Multimedia

CERN. Geneva

2016-01-01

Thanks to AdS/CFT, the analogy between black holes and thermal systems has become a practical tool, shedding light on thermalization, transport, and entanglement dynamics. Continuing in this vein, recent work has shown how chaos in the boundary CFT can be analyzed in terms of high energy scattering right on the horizon of the dual black hole. The analysis revolves around certain out-of-time-order correlation functions, which are simple diagnostics of the butterfly effect. We will review this work, along with a general bound on these functions that implies black holes are the most chaotic systems in quantum mechanics. (NB Room Change to Main Auditorium)

Snake velvet black: Hierarchical micro- and nanostructure enhances dark colouration in Bitis rhinoceros

Science.gov (United States)

Spinner, Marlene; Kovalev, Alexander; Gorb, Stanislav N.; Westhoff, Guido

2013-05-01

The West African Gaboon viper (Bitis rhinoceros) is a master of camouflage due to its colouration pattern. Its skin is geometrically patterned and features black spots that purport an exceptional spatial depth due to their velvety surface texture. Our study shades light on micromorphology, optical characteristics and principles behind such a velvet black appearance. We revealed a unique hierarchical pattern of leaf-like microstructures striated with nanoridges on the snake scales that coincides with the distribution of black colouration. Velvet black sites demonstrate four times lower reflectance and higher absorbance than other scales in the UV - near IR spectral range. The combination of surface structures impeding reflectance and absorbing dark pigments, deposited in the skin material, provides reflecting less than 11% of the light reflected by a polytetrafluoroethylene diffuse reflectance standard in any direction. A view-angle independent black structural colour in snakes is reported here for the first time.

Properties of black carbon and other insoluble light-absorbing particles in seasonal snow of northwestern China

Science.gov (United States)

Pu, Wei; Wang, Xin; Wei, Hailun; Zhou, Yue; Shi, Jinsen; Hu, Zhiyuan; Jin, Hongchun; Chen, Quanliang

2017-05-01

A large field campaign was conducted and 284 snow samples were collected at 38 sites in Xinjiang Province and 6 sites in Qinghai Province across northwestern China from January to February 2012. A spectrophotometer combined with chemical analysis was used to measure the insoluble light-absorbing particles (ILAPs) and chemical components in seasonal snow. The results indicate that the cleanest snow was found in northeastern Xinjiang along the border of China, and it presented an estimated black carbon (CBCest) of approximately 5 ng g-1. The dirtiest snow presented a CBCest of approximately 450 ng g-1 near industrial cities in Xinjiang. Overall, the CBCest of most of the snow samples collected in this campaign was in the range of 10-150 ng g-1. Vertical variations in the snowpack ILAPs indicated a probable shift in emission sources with the progression of winter. An analysis of the fractional contributions to absorption implied that organic carbon (OC) dominated the 450 nm absorption in Qinghai, while the contributions from BC and OC were comparable in Xinjiang. Finally, a positive matrix factorization (PMF) model was run to explore the sources of particulate light absorption, and the results indicated an optimal three-factor/source solution that included industrial pollution, biomass burning, and soil dust.

Black Hole Paradox Solved By NASA's Chandra

Science.gov (United States)

2006-06-01

Black holes are lighting up the Universe, and now astronomers may finally know how. New data from NASA's Chandra X-ray Observatory show for the first time that powerful magnetic fields are the key to these brilliant and startling light shows. It is estimated that up to a quarter of the total radiation in the Universe emitted since the Big Bang comes from material falling towards supermassive black holes, including those powering quasars, the brightest known objects. For decades, scientists have struggled to understand how black holes, the darkest objects in the Universe, can be responsible for such prodigious amounts of radiation. Animation of a Black Hole Pulling Matter from Companion Star Animation of a Black Hole Pulling Matter from Companion Star New X-ray data from Chandra give the first clear explanation for what drives this process: magnetic fields. Chandra observed a black hole system in our galaxy, known as GRO J1655-40 (J1655, for short), where a black hole was pulling material from a companion star into a disk. "By intergalactic standards J1655 is in our backyard, so we can use it as a scale model to understand how all black holes work, including the monsters found in quasars," said Jon M. Miller of the University of Michigan, Ann Arbor, whose paper on these results appears in this week's issue of Nature. Gravity alone is not enough to cause gas in a disk around a black hole to lose energy and fall onto the black hole at the rates required by observations. The gas must lose some of its orbital angular momentum, either through friction or a wind, before it can spiral inward. Without such effects, matter could remain in orbit around a black hole for a very long time. Illustration of Magnetic Fields in GRO J1655-40 Illustration of Magnetic Fields in GRO J1655-40 Scientists have long thought that magnetic turbulence could generate friction in a gaseous disk and drive a wind from the disk that carries angular momentum outward allowing the gas to fall inward

Study of the Light Absorption and Utilization in Monoculture and Intercropping of Three Medicinal Plants of Black Cumin (Nigella sativa L., Marigold (Calendula officinalis L. and Borage (Borago officinalis L.

Directory of Open Access Journals (Sweden)

P Naghipoor Dehkordi

2017-10-01

Full Text Available Introduction One of the components of sustainable agriculture is multiple cropping (such as intercropping. Intercropping means the use of a farm to produce two or more crops through a year. Diversity in agricultural systems is a reason for sustainability and widespread and better production, and better use of natural resources and environment, such as water, light and nutrients has priority to monoculture. Intercropping is one of agronomical strategies to increasing the absorption and efficiency of radiation absorption and use. In proper agronomical conditions that there is no limitation for crop growth, there is a linear relationship between dry matter and absorbed radiation and the slope of regression trend line between these two indices during growing season is radiation use efficiency (RUE. Radiation use efficiency (RUE relates biomass production to the photosynthetically active radiation (PAR intercepted by a plant or crop. Radiation use efficiency is dependent on light, temperature, vapor pressure deficit and factors inherent to plant species. Linear relationship between biomass and accumulated intercepted radiation has been demonstrated for several herbaceous plants (e.g., beans, soybean and lettuce and for a few tree species (e.g., willow, mesquite and juniper. The production of dry matter in conditions without any environmental stresses is a function of light absorption and efficiency of plant to production of dry matter from absorbed radiation. Materials and Methods In order to study RUE in intercropping pattern of three medicinal plants including marigold (Calendula officinalis, borage (Borago officinalis and black cumin (Nigella sativa in two and three species compared with their monoculture, an experiment was conducted based on a randomized complete block design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad in the growing season of 2013-2014. Treatments included 1:1 ratio of black cumin

Rare earth elements behavior in Peruibe black mud

International Nuclear Information System (INIS)

Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da

2015-01-01

Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

Rare earth elements behavior in Peruibe black mud

Energy Technology Data Exchange (ETDEWEB)

Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da, E-mail: jeffkoy@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

Foundations of Black Hole Accretion Disk Theory

Directory of Open Access Journals (Sweden)

Marek A. Abramowicz

2013-01-01

Full Text Available This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks, Shakura-Sunyaev (thin disks, slim disks, and advection-dominated accretion flows (ADAFs. After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs.

Foundations of Black Hole Accretion Disk Theory.

Science.gov (United States)

Abramowicz, Marek A; Fragile, P Chris

2013-01-01

This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks), Shakura-Sunyaev (thin) disks, slim disks, and advection-dominated accretion flows (ADAFs). After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs).

Entrepreneurs` Cognitive and Decision Making Styles

Directory of Open Access Journals (Sweden)

Mahmoud Motvaseli

2015-12-01

Full Text Available The main purpose of this study is to explore the relation between decision-making styles which are measured by the General decision-making style (GDMS test and information processing styles which are often termed cognitive styles and are, in this study, measured by Cognitive Style Inventory. The authors directed a survey research on 162 Iranian students. Structural equation modeling techniques were used to measure the impact of cognitive styles on decision-making styles. The authors found that cognitive styles have a positive impact on decision-making styles. In spite of the abundant research on factors that affect decision-making styles, few researches have tested the relationship between cognitive styles and decision-making styles. This study examines the impact of cognitive styles on decision-making styles in Iran. This study, like most research paper studies, cannot easily be generalized. Furthermore, the results of this study could be affected by economic conditions.

Black holes at neutrino telescopes

International Nuclear Information System (INIS)

Kowalski, M.; Ringwald, A.; Tu, H.

2002-01-01

In scenarios with extra dimensions and TeV-scale quantum gravity, black holes are expected to be produced in the collision of light particles at center-of-mass energies above the fundamental Planck scale with small impact parameters. Black hole production and evaporation may thus be studied in detail at the large hadron collider (LHC). But even before the LHC starts operating, neutrino telescopes such as AMANDA/IceCube, ANTARES, Baikal, and RICE have an opportunity to search for black hole signatures. Black hole production in the scattering of ultrahigh energy cosmic neutrinos on nucleons in the ice or water may initiate cascades and through-going muons with distinct characteristics above the Standard Model rate. In this Letter, we investigate the sensitivity of neutrino telescopes to black hole production and compare it to the one expected at the Pierre Auger Observatory, an air shower array currently under construction, and at the LHC. We find that, already with the currently available data, AMANDA and RICE should be able to place sensible constraints in black hole production parameter space, which are competitive with the present ones from the air shower facilities Fly's Eye and AGASA. In the optimistic case that a ultrahigh energy cosmic neutrino flux significantly higher than the one expected from cosmic ray interactions with the cosmic microwave background radiation is realized in nature, one even has discovery potential for black holes at neutrino telescopes beyond the reach of LHC. (orig.)

Traffic Light Options

DEFF Research Database (Denmark)

Jørgensen, Peter Løchte

This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... 2006, and supervisory authorities in many other European countries have implemented similar regulation. Traffic light options are therefore likely to attract the attention of a wider audience of pension fund managers in the future. Focusing on the valuation of the traffic light option we set up a Black...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

Traffic Light Options

DEFF Research Database (Denmark)

Jørgensen, Peter Løchte

2007-01-01

This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... 2006, and supervisory authorities in many other European countries have implemented similar regulation. Traffic light options are therefore likely to attract the attention of a wider audience of pension fund managers in the future. Focusing on the valuation of the traffic light option we set up a Black...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

Black to Black

DEFF Research Database (Denmark)

Langkjær, Michael Alexander

2012-01-01

Pop musicians performing in black stage costume take advantage of cultural traditions relating to matters black. Stylistically, black is a paradoxical color: although a symbol of melancholy, pessimism, and renunciation, black also expresses minimalist modernity and signifies exclusivity (as is hi...

Why I Teach "Black Boy."

Science.gov (United States)

Mahle, Benjamin

1983-01-01

Argues that Richard Wright's "Black Boy" is appropriate for ninth-grade students because it combines an exciting story of survival with effective prose, forces readers to try to understand their own experiences in the light of the protagonist's, and intimately involves students in such universal concerns as suffering, violence, and…

Smoking Trends and Disparities Among Black and Non-Hispanic Whites in California.

Science.gov (United States)

Sakuma, Kari-Lyn Kobayakawa; Felicitas, Jamie; Fagan, Pebbles; Gruder, Charles L; Blanco, Lyzette; Cappelli, Christopher; Trinidad, Dennis R

2015-12-01

The current study examined disparities in smoking trends across Blacks and non-Hispanic Whites in California. Data from the 1996 to 2008 California Tobacco Survey were analyzed to examine trends in smoking behaviors and cessation across Blacks and non-Hispanic Whites. A decrease in overall ever and current smoking was observed for both Black and non-Hispanic Whites across the 12-year time period. A striking decrease in proportions of heavy daily smokers for both Black and non-Hispanic Whites were observed. Proportions of light and intermittent smokers and moderate daily smokers displayed modest increases for Blacks, but large increases for non-Hispanic Whites. Increases in successful cessation were also observed for Blacks and, to a lesser extent, for non-Hispanic Whites. Smoking behavior and cessation trends across Blacks and non-Hispanic Whites were revealing. The decline in heavy daily and former smokers may demonstrate the success and effectiveness of tobacco control efforts in California. However, the increase in proportions of light and intermittent smokers and moderate daily smokers for both Blacks and non-Hispanic Whites demonstrates a need for tobacco cessation efforts focused on lighter smokers. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Relationships between Humor Styles and Family Functioning in Parents of Children with Disabilities

Science.gov (United States)

Rieger, Alicja; McGrail, J. Patrick

2015-01-01

The humor styles and family functioning of parents of children with disabilities are understudied subjects. This study seeks to shed quantitative light on these areas. Seventy-two parents of children with disabilities completed the "Family Adaptability and Cohesion Evaluation Scales" (FACES IV) and the "Humor Styles…

Identity style and coping strategies.

Science.gov (United States)

Berzonsky, M D

1992-12-01

This study examined the relationship between identity style and strategies used to cope with stressors that potentially threaten one's sense of identity. Identity style refers to differences in the way individuals construct and revise or maintain their sense of identity. An informational style involves actively seeking out, evaluating, and utilizing self-relevant information. A normative style highlights the expectations and standards of significant others. A diffuse/avoidant style is characterized by procrastination and situation-specific reactions. Late-adolescent college subjects were administered measures of identity style, ways of coping with academic stressors, and test anxiety. Within this self-as-student context, subjects with diffuse and normative identity styles employed avoidant-oriented coping strategies (wishful thinking, distancing, and tension reduction). An informational style was associated with deliberate, problem-focused coping. Findings are discussed in terms of a process model of identity development.

Put Your Style at Stake

DEFF Research Database (Denmark)

Johnsen, Christian Garmann; Olaison, Lena; Meier Sørensen, Bent

2018-01-01

This article uses the concept of style to rethink sustainable entrepreneurship. Our point of departure is the conceptual distinction between organization as style made durable and entrepreneurship as the disruption of style. We show that style is not simply an aesthetic category, but rather what...... enable the creation of new styles. In order to conceptualize this creative process, we explore how play can create disharmonies within the organization, but we also maintain that any new practice will remain marginal without a collective assemblage capable of adopting it. On this basis, we argue...... that sustainable entrepreneurship consists of making an environmentally friendly and socially conscious style durable, but also of disrupting such a style. In order to illustrate our argument, we use the example of the sustainable smartphone producer Fairphone. In conclusion, we argue that the concept of style may...

Depression, patient characteristics, and attachment style: correlates and mediators of medication treatment adherence in a racially diverse primary care sample.

Science.gov (United States)

Hooper, Lisa M; Tomek, Sara; Roter, Debra; Carson, Kathryn A; Mugoya, George; Cooper, Lisa A

2016-03-01

The depth and breadth of problems related to depressive symptomatology and optimal treatment outcomes, including medication treatment adherence, have long been documented in the literature. Missing are clear explanations as to what factors and patient characteristics may account for lack of medication treatment adherence. The two objectives of the current study were to examine the predictive strength of depression, patient characteristics, and patient attachment style regarding medication treatment adherence and to consider the extent to which attachment styles mediate the relation between depression and medication treatment adherence. Participants in the present study were 237 racially diverse American primary care patients with a diagnosis of hypertension who were participants in a clinical trial. Depression, patient characteristics, attachment style, and medication treatment adherence were assessed. Partly consistent with our four hypotheses, the following results were found: (a) Black American, younger, never married, and poorer patients had lower medication treatment adherence (b) depression was significantly associated with lower self-reported medication adherence; (c) insecure-dismissing attachment style was related to lower medication adherence; and (d) insecure-dismissing attachment style mediates the relation between depression and medication treatment adherence by exacerbating the negative association. Physicians and other primary care providers should consider how depressive symptomatology, patient characteristics, and attachment style may inform the treatment plans they put forward and the extent to which patients may adhere to those treatment plans.

Relativistic boost as the cause of periodicity in a massive black-hole binary candidate.

Science.gov (United States)

D'Orazio, Daniel J; Haiman, Zoltán; Schiminovich, David

2015-09-17

Because most large galaxies contain a central black hole, and galaxies often merge, black-hole binaries are expected to be common in galactic nuclei. Although they cannot be imaged, periodicities in the light curves of quasars have been interpreted as evidence for binaries, most recently in PG 1302-102, which has a short rest-frame optical period of four years (ref. 6). If the orbital period of the black-hole binary matches this value, then for the range of estimated black-hole masses, the components would be separated by 0.007-0.017 parsecs, implying relativistic orbital speeds. There has been much debate over whether black-hole orbits could be smaller than one parsec (ref. 7). Here we report that the amplitude and the sinusoid-like shape of the variability of the light curve of PG 1302-102 can be fitted by relativistic Doppler boosting of emission from a compact, steadily accreting, unequal-mass binary. We predict that brightness variations in the ultraviolet light curve track those in the optical, but with a two to three times larger amplitude. This prediction is relatively insensitive to the details of the emission process, and is consistent with archival ultraviolet data. Follow-up ultraviolet and optical observations in the next few years can further test this prediction and confirm the existence of a binary black hole in the relativistic regime.

Film Noir Style Genealogy

OpenAIRE

Rietuma, Dita

2012-01-01

Annotation for the Doctoral Work Film Noir Style Genealogy (The Genealogy of the Film Noir Style) The doctoral work topic Film Noir Style Genealogy encompasses traditionally approved world film theory views on the concept of film noir and its related cinematographic heritage, and an exploration of its evolution and distinctive style, including – the development of film noir in the USA, Europe, and also in Latvia, within the context of both socio-political progression and the paradigm of m...

Parenting styles, feeding styles, and their influence on child obesogenic behaviors and body weight. A review.

Science.gov (United States)

Vollmer, Rachel L; Mobley, Amy R

2013-12-01

With recommendations to include parents as targets for childhood obesity interventions, there is a need to review the relationship of general parenting influences on childhood obesity. Therefore, the aim of this review is to examine the existing literature regarding the influence of parenting style and/or feeding styles on childhood obesogenic behaviors and body weight. Research articles related to parenting style (n=40) and parental feeding style (n=11) were identified and reviewed. An authoritative style appears to be the most protective parenting and feeding style while the indulgent feeding style is consistently associated with negative health outcomes. Overall, results for parenting style studies are inconsistent due to differences in conceptualization and measurement, while the results for feeding styles are much more cohesive. The literature is lacking in the ability to describe the interplay between parenting and feeding styles and child obesity risk. Recommendations for future research and interventions are discussed in regards to feeding style and influences on childhood obesity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Values and love styles in Turkey and Great Britain: an intercultural and intracultural comparison.

Science.gov (United States)

Sanrı, Çağla; Goodwin, Robin

2013-01-01

Little previous research has examined the relationship between values and love styles, and none has done so across cultures or intracultural regions. This research was the first attempt to explore the correlation between individual-level values and love styles, and examined both within- and between-cultural variations in love styles. In this study 224 participants from Turkey and Britain, from urban or rural locations, completed the Portrait Values Questionnaire and the Love Attitudes Scale measure of love styles. Pancultural analyses demonstrated significant correlations between certain value dimensions and love styles. In particular, agape (selfless love) was positively correlated with self-transcendence, ludus (game-playing love) was positively correlated with self-enhancement, and pragma (realistic love) was positively correlated with conservation. The inclusion of location and nationality and their interactions with values in the multiple regression analyses significantly increased the variance explained by values for five of the six love styles. Multivariate analyses indicated that ludus, storge, mania, and pragma were all significantly higher among Turkish respondents; pragma, mania, and agape all higher amongst rural respondents. Eros was highest among rural British respondents; storge, pragma, and agape highest among rural Turks. When these culture effects were explored, conservation significantly mediated the relationship between the groups of more conservative rural Turks (versus other participants) and both pragmatic and storgic love styles. Findings are discussed in the light of disparities in values and relationship styles within cultures, and the need to include both intracultural and intercultural variations in cross cultural research.

Learning styles in otolaryngology fellowships.

Science.gov (United States)

Varela, David A Diaz Voss; Malik, Mohammad U; Laeeq, Kulsoom; Pandian, Vinciya; Brown, David J; Weatherly, Robert A; Cummings, Charles W; Bhatti, Nasir I

2011-12-01

Previous studies have identified a predominant learning style in trainees from different specialties, more recently in otolaryngology residents. The purpose of our study was to determine a predominant learning style within otolaryngology fellowships and to identify any differences between otolaryngology fellows and residents. We conducted a survey of otolaryngology fellows at 25 otolaryngology fellowship programs accredited by the Accreditation Council for Graduate Medical Education. We emailed Kolb's Learning Style Index version 3.1 to 16 pediatric otolaryngology (PO) and 24 otology/neurotology (ON) fellows. This index is a widely used 12-item questionnaire. The participants answered each item in the questionnaire as it applied to their preferred learning style: accommodating, converging, diverging, or assimilating. Results were then analyzed and compared between each subspecialty and the previously reported preferred styles of otolaryngology residents. Ten PO and 20 ON fellows completed the survey, with an overall response rate of 75%. PO and ON fellows (60% of each group) preferred a learning style that was "balanced" across all four styles. For ON fellows, 35% preferred converging and 5% preferred accommodating styles. For PO fellows, converging and accommodating styles accounted for 20% each. It was previously reported that 74.4% of otolaryngology residents prefer either converging or accommodating styles. We believe that the fellowship training environment calls for fellows to use more than one learning style to become proficient physicians, hence the trend toward potentially developing a balanced style when at this level. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Quantum catastrophe of slow light

OpenAIRE

Leonhardt, Ulf

2001-01-01

Catastrophes are at the heart of many fascinating optical phenomena. The rainbow, for example, is a ray catastrophe where light rays become infinitely intense. The wave nature of light resolves the infinities of ray catastrophes while drawing delicate interference patterns such as the supernumerary arcs of the rainbow. Black holes cause wave singularities. Waves oscillate with infinitely small wave lengths at the event horizon where time stands still. The quantum nature of light avoids this h...

Profiling and Utilizing Learning Style. NASSP Learning Style Series.

Science.gov (United States)

Keefe, James W., Ed.

In 1986, the National Association of Secondary School Principals, with the assistance of a national task force, published the NASSP Learning Style Profile (LSP) for diagnosis of the cognitive styles, perceptual response tendencies, and instructional preferences of middle level and senior high school students. This monograph offers a short course…

Coping Styles, Aggression and Interpersonal Conflicts among Depressed and Non-Depressed People.

Science.gov (United States)

Nazir, Amber; Mohsin, Humaira

2013-01-01

The present study compared people with depressive symptoms and people without depressive symptoms with reference to their coping styles, level of aggression and interpersonal conflicts. A purposive sample of 128 people (64 depressed and 64 normal controls)was selected from four different teaching hospitals of Lahore. Both the groups were matched on four demographic levels i.e. age, gender, education and monthly income. Symptom Checklist-R was used to screen out depressed and non-depressed people. The Brief COPE, the Aggression Questionnaire and the Bergen Social Relationship Scale were used to assess coping styles, aggression and interpersonal conflicts respectively. The Independent t-test was used to compare the groups. Binary logistic Regression was also carried out to predict the role of research variables in causing depression. The results showed that level of aggression and interpersonal conflict was significantly more in people with depressive symptoms as compared to control group. On the other hand control group was using more adaptive coping styles than people with depressive symptoms but no difference was found in the use of maladaptive coping styles. The present findings revealed that coping styles, aggression and interpersonal conflicts play important role in depression. Therefore, these dimensions must be considered while dealing with the depressive patients. Implications for preventive work are also discussed in the light of previous researches.

Coping Styles, Aggression and Interpersonal Conflicts among Depressed and Non-Depressed People

Directory of Open Access Journals (Sweden)

Amber Nazir

2013-06-01

Full Text Available Background: The present study compared people with depressive symp¬toms and people without depressive symptoms with reference to their coping styles, level of aggression and interpersonal conflicts.Methods: A purposive sample of 128 people (64 depressed and 64 normal controls was selected from four different teaching hospitals of Lahore. Both the groups were matched on four demographic levels i.e. age, gender, education and monthly income. Symptom Checklist-R was used to screen out depressed and non-depressed people. The Brief COPE, the Aggres¬sion Questionnaire and the Bergen Social Relationship Scale were used to assess coping styles, aggression and interpersonal conflicts respectively. The Independent t-test was used to compare the groups. Binary logistic Regression was also carried out to predict the role of research variables in causing depression.Results: The results showed that level of aggression and interpersonal conflict was significantly more in people with depressive symptoms as compared to control group. On the other hand control group was using more adaptive coping styles than people with depressive symptoms but no difference was found in the use of maladaptive coping styles. Conclusion: The present findings revealed that coping styles, aggression and interpersonal conflicts play important role in depression. Therefore, these dimen-sions must be considered while dealing with the depressive patients. Implications for preventive work are also discussed in the light of previous researches.

Personal style of the therapist, attachment style and personality trait

Directory of Open Access Journals (Sweden)

Gabriel Genise

2015-12-01

Full Text Available The aim of this study is to analyze the relationship between the personal style of the therapist, attachment style and personality trait. It was used the personal style of the therapist questionnaire (PST – Q, the Argentinean attachment inventory and the big five inventory. The study sample consisted of 120 psychotherapists average age of 36.28 years (SD = 9.65, and the average years of experience was 7.90 years (SD = 8.04. The analysis of the results showed that there is a positive, significant and low intensity between the personality factor of openness to experience and personal style of involvement, a negative correlation, significant and of medium intensity between low extraversion factor correlation and mode not anxious romantic attachment and a significant positive relationship between the low–intensity factor neuroticism personality and how anxious romantic attachment. 

Leadership Styles

Science.gov (United States)

Val, Carlin; Kemp, Jess

2012-01-01

This study examines how a group's dynamic changes under the influence of different leadership styles, and determines what leadership style works best in a large group expedition. The main question identified was "What roles can a leader play in affecting the dynamic of a large group while partaking in a field expedition?" The following…

Evaluation of solid particle number and black carbon for very low particulate matter emissions standards in light-duty vehicles.

Science.gov (United States)

Chang, M-C Oliver; Shields, J Erin

2017-06-01

To reliably measure at the low particulate matter (PM) levels needed to meet California's Low Emission Vehicle (LEV III) 3- and 1-mg/mile particulate matter (PM) standards, various approaches other than gravimetric measurement have been suggested for testing purposes. In this work, a feasibility study of solid particle number (SPN, d50 = 23 nm) and black carbon (BC) as alternatives to gravimetric PM mass was conducted, based on the relationship of these two metrics to gravimetric PM mass, as well as the variability of each of these metrics. More than 150 Federal Test Procedure (FTP-75) or Supplemental Federal Test Procedure (US06) tests were conducted on 46 light-duty vehicles, including port-fuel-injected and direct-injected gasoline vehicles, as well as several light-duty diesel vehicles equipped with diesel particle filters (LDD/DPF). For FTP tests, emission variability of gravimetric PM mass was found to be slightly less than that of either SPN or BC, whereas the opposite was observed for US06 tests. Emission variability of PM mass for LDD/DPF was higher than that of both SPN and BC, primarily because of higher PM mass measurement uncertainties (background and precision) near or below 0.1 mg/mile. While strong correlations were observed from both SPN and BC to PM mass, the slopes are dependent on engine technologies and driving cycles, and the proportionality between the metrics can vary over the course of the test. Replacement of the LEV III PM mass emission standard with one other measurement metric may imperil the effectiveness of emission reduction, as a correlation-based relationship may evolve over future technologies for meeting stringent greenhouse standards. Solid particle number and black carbon were suggested in place of PM mass for the California LEV III 1-mg/mile FTP standard. Their equivalence, proportionality, and emission variability in comparison to PM mass, based on a large light-duty vehicle fleet examined, are dependent on engine

Style and creativity in design

CERN Document Server

Chan, Chiu-Shui

2015-01-01

This book looks at causative reasons behind creative acts and stylistic expressions. It explores how creativity is initiated by design cognition and explains relationships between style and creativity. The book establishes a new cognitive theory of style and creativity in design and provides designers with insights into their own cognitive processes and styles of thinking, supporting a better understanding of the qualities present in their own design.  An explanation of the nature of design cognition begins this work, with a look at how design knowledge is formulated, developed, structured and utilized, and how this utilization triggers style and creativity. The author goes on to review historical studies of style, considering a series of psychological experiments relating to the operational definition, degree, measurement, and creation of style. The work conceptually summarizes the recognition of individual style in products, as well as the creation of such styles as a process before reviewing studies on cr...

[Androgen levels, parenting styles and aggressive behavior in 5-6-year-old boys and girls].

Science.gov (United States)

Sánchez-Martín, José R; Azurmendi Imaz, Aitziber; Fano Ardanaz, Eduardo; Braza Lloret, Francisco; Muñoz Sánchez, José M; Carreras de Alba, María R

2009-02-01

Androgen levels, parenting styles and aggressive behavior in 5-6-year-old boys and girls. This study explores the relationship between androgen levels, parenting styles, and physical, verbal, and indirect aggression measures in 5-6-year-old children. 129 children (60 boys and 69 girls) were assessed in relation to their aggression levels using a peer-rating technique. Parents completed the Parenting Styles and Dimensions Questionnaire, from which the different parenting styles were obtained. Testosterone, androstenedione and dehydroepiandrosterone (DHEA) were measured using an enzymoimmunoassay technique in saliva samples. A regression analysis indicated that the directive mother-androstenedione interaction at the age of 5 was predictive of physical aggression at the age of 6. In specific terms, the results showed that, in boys with high androstenedione levels, directive maternal behavior is associated with physical aggression. The results are subsequently discussed in light of postulates related to parenting characteristic of developmental psychology and we suggest a potential link of our results with the hypothesis of maternal dominance.

The mediational pathway among parenting styles, attachment styles and self-regulation with addiction susceptibility of adolescents

Directory of Open Access Journals (Sweden)

Ali Zeinali

2011-01-01

Conclusions: The findings of present study suggest the authoritative and permissive parenting styles as the most efficient styles and authoritarian and neglectful parenting styles as the most inefficient styles in terms of addiction susceptibility. Accordingly, efficient parenting style training to parents should be the main goal of drug demand reduction program.

Theory of a slow-light catastrophe

International Nuclear Information System (INIS)

Leonhardt, Ulf

2002-01-01

In diffraction catastrophes such as the rainbow, the wave nature of light resolves ray singularities and draws delicate interference patterns. In quantum catastrophes such as the black hole, the quantum nature of light resolves wave singularities and creates characteristic quantum effects related to Hawking radiation. This paper describes the theory behind a recent proposal [U. Leonhardt, Nature (London) 415, 406 (2002)] to generate a quantum catastrophe of slow light

Theory of a slow-light catastrophe

Science.gov (United States)

Leonhardt, Ulf

2002-04-01

In diffraction catastrophes such as the rainbow, the wave nature of light resolves ray singularities and draws delicate interference patterns. In quantum catastrophes such as the black hole, the quantum nature of light resolves wave singularities and creates characteristic quantum effects related to Hawking radiation. This paper describes the theory behind a recent proposal [U. Leonhardt, Nature (London) 415, 406 (2002)] to generate a quantum catastrophe of slow light.

Theory of a Slow-Light Catastrophe

OpenAIRE

Leonhardt, Ulf

2001-01-01

In diffraction catastrophes such as the rainbow the wave nature of light resolves ray singularities and draws delicate interference patterns. In quantum catastrophes such as the black hole the quantum nature of light resolves wave singularities and creates characteristic quantum effects related to Hawking radiation. The paper describes the theory behind a recent proposal [U. Leonhardt, arXiv:physics/0111058, Nature (in press)] to generate a quantum catastrophe of slow light.

Using measurements for evaluation of black carbon modeling

Directory of Open Access Journals (Sweden)

S. Gilardoni

2011-01-01

Full Text Available The ever increasing use of air quality and climate model assessments to underpin economic, public health, and environmental policy decisions makes effective model evaluation critical. This paper discusses the properties of black carbon and light attenuation and absorption observations that are the key to a reliable evaluation of black carbon model and compares parametric and nonparametric statistical tools for the quantification of the agreement between models and observations. Black carbon concentrations are simulated with TM5/M7 global model from July 2002 to June 2003 at four remote sites (Alert, Jungfraujoch, Mace Head, and Trinidad Head and two regional background sites (Bondville and Ispra. Equivalent black carbon (EBC concentrations are calculated using light attenuation measurements from January 2000 to December 2005. Seasonal trends in the measurements are determined by fitting sinusoidal functions and the representativeness of the period simulated by the model is verified based on the scatter of the experimental values relative to the fit curves. When the resolution of the model grid is larger than 1° × 1°, it is recommended to verify that the measurement site is representative of the grid cell. For this purpose, equivalent black carbon measurements at Alert, Bondville and Trinidad Head are compared to light absorption and elemental carbon measurements performed at different sites inside the same model grid cells. Comparison of these equivalent black carbon and elemental carbon measurements indicates that uncertainties in black carbon optical properties can compromise the comparison between model and observations. During model evaluation it is important to examine the extent to which a model is able to simulate the variability in the observations over different integration periods as this will help to identify the most appropriate timescales. The agreement between model and observation is accurately described by the overlap of

Ultraviolet safety assessments of insect light traps.

Science.gov (United States)

Sliney, David H; Gilbert, David W; Lyon, Terry

2016-01-01

Near-ultraviolet (UV-A: 315-400 nm), "black-light," electric lamps were invented in 1935 and ultraviolet insect light traps (ILTs) were introduced for use in agriculture around that time. Today ILTs are used indoors in several industries and in food-service as well as in outdoor settings. With recent interest in photobiological lamp safety, safety standards are being developed to test for potentially hazardous ultraviolet emissions. A variety of UV "Black-light" ILTs were measured at a range of distances to assess potential exposures. Realistic time-weighted human exposures are shown to be well below current guidelines for human exposure to ultraviolet radiation. These UV-A exposures would be far less than the typical UV-A exposure in the outdoor environment. Proposals are made for realistic ultraviolet safety standards for ILT products.

Ultraspinning limits and super-entropic black holes

Energy Technology Data Exchange (ETDEWEB)

Hennigar, Robie A. [Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Kubizňák, David [Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Perimeter Institute, 31 Caroline St. N., Waterloo, Ontario, N2L 2Y5 (Canada); Mann, Robert B. [Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Musoke, Nathan [Perimeter Institute, 31 Caroline St. N., Waterloo, Ontario, N2L 2Y5 (Canada)

2015-06-16

By employing the new ultraspinning limit we construct novel classes of black holes with non-compact event horizons and finite horizon area and study their thermodynamics. Our ultraspinning limit can be understood as a simple generating technique that consists of three steps: i) transforming the known rotating AdS black hole solution to a special coordinate system that rotates (in a given 2-plane) at infinity ii) boosting this rotation to the speed of light iii) compactifying the corresponding azimuthal direction. In so doing we qualitatively change the structure of the spacetime since it is no longer possible to return to a frame that does not rotate at infinity. The obtained black holes have non-compact horizons with topology of a sphere with two punctures. The entropy of some of these exceeds the maximal bound implied by the reverse isoperimetric inequality, such black holes are super-entropic.

Ultraspinning limits and super-entropic black holes

Science.gov (United States)

Hennigar, Robie A.; Kubizňák, David; Mann, Robert B.; Musoke, Nathan

2015-06-01

By employing the new ultraspinning limit we construct novel classes of black holes with non-compact event horizons and finite horizon area and study their thermo-dynamics. Our ultraspinning limit can be understood as a simple generating technique that consists of three steps: i) transforming the known rotating AdS black hole solution to a special coordinate system that rotates (in a given 2-plane) at infinity ii) boosting this rotation to the speed of light iii) compactifying the corresponding azimuthal direction. In so doing we qualitatively change the structure of the spacetime since it is no longer pos-sible to return to a frame that does not rotate at infinity. The obtained black holes have non-compact horizons with topology of a sphere with two punctures. The entropy of some of these exceeds the maximal bound implied by the reverse isoperimetric inequality, such black holes are super-entropic.

Radiative properties of optical board embedded with optical black holes

International Nuclear Information System (INIS)

Qiu, J.; Liu, L.H.; Hsu, P.-F.

2011-01-01

Unique radiative properties, such as wavelength-selective transmission or absorption, have been intensively studied. Historically, geometries for wavelength-selective of light absorption were developed based on metallic periodical structures, which were only applied in the case of TM wave incidence due to the excitation of surface plasmons. In this paper, we develop an alternative approach to selective wavelength of light absorption (both TE and TM waves), based on an optical board periodical embedded with optical black holes. Numerical work was carried out to study such structure's radiative properties within the wavelength range of 1-100 μm. The electromagnetic wave transmission through such a structure is predicted by solving Maxwell's equations using the finite-difference time-domain (FDTD) method. Spectral absorptance varies with the period of optical black holes. When the incidence wavelength is much larger than the inner core radius, most of the light energy will be transmitted through the inner core. Otherwise, the energy will be mainly absorbed. Numerical results of the radiative properties of the optical board with different incidence wavelengths are also obtained. The effect of the oblique incidence wave is investigated. This study helps us gain a better understanding of the radiative properties of an optical board embedded with optical black holes and develop an alternative approach to selective light absorption.

Configurational entropy of anti-de Sitter black holes

International Nuclear Information System (INIS)

Braga, Nelson R.F.; Rocha, Roldão da

2017-01-01

Recent studies indicate that the configurational entropy is an useful tool to investigate the stability and (or) the relative dominance of states for diverse physical systems. Recent examples comprise the connection between the variation of this quantity and the relative fraction of light mesons and glueballs observed in hadronic processes. Here we develop a technique for defining a configurational entropy for an AdS-Schwarzschild black hole. The achieved result corroborates consistency with the Hawking–Page phase transition. Namely, the dominance of the black hole configurational entropy will be shown to increase with the temperature. In order to verify the consistency of the new procedure developed here, we also consider the case of black holes in flat space-time. For such a black hole, it is known that evaporation leads to instability. The configurational entropy obtained for the flat space case is thoroughly consistent with the physical expectation. In fact, we show that the smaller the black holes, the more unstable they are. So, the configurational entropy furnishes a reliable measure for stability of black holes.

Configurational entropy of anti-de Sitter black holes

Energy Technology Data Exchange (ETDEWEB)

Braga, Nelson R.F., E-mail: braga@if.ufrj.br [Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, RJ 21941-972 (Brazil); Rocha, Roldão da, E-mail: roldao.rocha@ufabc.edu.br [Centro de Matemática, Computação e Cognição, Universidade Federal do ABC – UFABC, 09210-580, Santo André (Brazil)

2017-04-10

Recent studies indicate that the configurational entropy is an useful tool to investigate the stability and (or) the relative dominance of states for diverse physical systems. Recent examples comprise the connection between the variation of this quantity and the relative fraction of light mesons and glueballs observed in hadronic processes. Here we develop a technique for defining a configurational entropy for an AdS-Schwarzschild black hole. The achieved result corroborates consistency with the Hawking–Page phase transition. Namely, the dominance of the black hole configurational entropy will be shown to increase with the temperature. In order to verify the consistency of the new procedure developed here, we also consider the case of black holes in flat space-time. For such a black hole, it is known that evaporation leads to instability. The configurational entropy obtained for the flat space case is thoroughly consistent with the physical expectation. In fact, we show that the smaller the black holes, the more unstable they are. So, the configurational entropy furnishes a reliable measure for stability of black holes.

Holographic shell model: Stack data structure inside black holes?

Science.gov (United States)

Davidson, Aharon

2014-03-01

Rather than tiling the black hole horizon by Planck area patches, we suggest that bits of information inhabit, universally and holographically, the entire black core interior, a bit per a light sheet unit interval of order Planck area difference. The number of distinguishable (tagged by a binary code) configurations, counted within the context of a discrete holographic shell model, is given by the Catalan series. The area entropy formula is recovered, including Cardy's universal logarithmic correction, and the equipartition of mass per degree of freedom is proven. The black hole information storage resembles, in the count procedure, the so-called stack data structure.

Style representation in design grammars

DEFF Research Database (Denmark)

Ahmad, Sumbul; Chase, Scott Curland

2012-01-01

The concept of style is relevant for both the analysis and synthesis of designs. New styles are often formed by the adaptation of previous ones based on changes in design criteria and context. A formal characterization of style is given by shape grammars, which describe the compositional rules...... underlying a set of designs. Stylistic change can be modelled by grammar transformations, which allow the transformation of the structure and vocabulary of a grammar that is used to describe a particular style. In order for grammars to be useful beyond a single application, they should have the capability...... to be transformed according to changing design style needs. Issues of formalizing stylistic change necessitate a lucid and formal definition of style in the design language generated by a grammar. Furthermore, a significant aspect of the definition of style is the representation of aesthetic qualities attributed...

General relativistic radiative transfer code in rotating black hole space-time: ARTIST

Science.gov (United States)

Takahashi, Rohta; Umemura, Masayuki

2017-02-01

We present a general relativistic radiative transfer code, ARTIST (Authentic Radiative Transfer In Space-Time), that is a perfectly causal scheme to pursue the propagation of radiation with absorption and scattering around a Kerr black hole. The code explicitly solves the invariant radiation intensity along null geodesics in the Kerr-Schild coordinates, and therefore properly includes light bending, Doppler boosting, frame dragging, and gravitational redshifts. The notable aspect of ARTIST is that it conserves the radiative energy with high accuracy, and is not subject to the numerical diffusion, since the transfer is solved on long characteristics along null geodesics. We first solve the wavefront propagation around a Kerr black hole that was originally explored by Hanni. This demonstrates repeated wavefront collisions, light bending, and causal propagation of radiation with the speed of light. We show that the decay rate of the total energy of wavefronts near a black hole is determined solely by the black hole spin in late phases, in agreement with analytic expectations. As a result, the ARTIST turns out to correctly solve the general relativistic radiation fields until late phases as t ˜ 90 M. We also explore the effects of absorption and scattering, and apply this code for a photon wall problem and an orbiting hotspot problem. All the simulations in this study are performed in the equatorial plane around a Kerr black hole. The ARTIST is the first step to realize the general relativistic radiation hydrodynamics.

Varying constants, black holes, and quantum gravity

International Nuclear Information System (INIS)

Carlip, S.

2003-01-01

Tentative observations and theoretical considerations have recently led to renewed interest in models of fundamental physics in which certain 'constants' vary in time. Assuming fixed black hole mass and the standard form of the Bekenstein-Hawking entropy, Davies, Davis and Lineweaver have argued that the laws of black hole thermodynamics disfavor models in which the fundamental electric charge e changes. I show that with these assumptions, similar considerations severely constrain 'varying speed of light' models, unless we are prepared to abandon cherished assumptions about quantum gravity. Relaxation of these assumptions permits sensible theories of quantum gravity with ''varying constants,'' but also eliminates the thermodynamic constraints, though the black hole mass spectrum may still provide some restrictions on the range of allowable models

NASA's Chandra Finds Black Holes Are "Green"

Science.gov (United States)

2006-04-01

Black holes are the most fuel efficient engines in the Universe, according to a new study using NASA's Chandra X-ray Observatory. By making the first direct estimate of how efficient or "green" black holes are, this work gives insight into how black holes generate energy and affect their environment. The new Chandra finding shows that most of the energy released by matter falling toward a supermassive black hole is in the form of high-energy jets traveling at near the speed of light away from the black hole. This is an important step in understanding how such jets can be launched from magnetized disks of gas near the event horizon of a black hole. Illustration of Fuel for a Black Hole Engine Illustration of Fuel for a Black Hole Engine "Just as with cars, it's critical to know the fuel efficiency of black holes," said lead author Steve Allen of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, and the Stanford Linear Accelerator Center. "Without this information, we cannot figure out what is going on under the hood, so to speak, or what the engine can do." Allen and his team used Chandra to study nine supermassive black holes at the centers of elliptical galaxies. These black holes are relatively old and generate much less radiation than quasars, rapidly growing supermassive black holes seen in the early Universe. The surprise came when the Chandra results showed that these "quiet" black holes are all producing much more energy in jets of high-energy particles than in visible light or X-rays. These jets create huge bubbles, or cavities, in the hot gas in the galaxies. Animation of Black Hole in Elliptical Galaxy Animation of Black Hole in Elliptical Galaxy The efficiency of the black hole energy-production was calculated in two steps: first Chandra images of the inner regions of the galaxies were used to estimate how much fuel is available for the black hole; then Chandra images were used to estimate the power required to produce

The behavior style of coaches

Directory of Open Access Journals (Sweden)

Mijanović Mihajlo

2016-01-01

Full Text Available On the sample by 121 perspective young athletes was carried out the researching in the aim to establish the behavior style of coaches. The relevant information was obtained through the validated questionnaires of Chelladura and Saleha (1980. The questionnaire contains 40 questions which directly determine 5 behavior styles of coaches. All questions possess the scale by 5 levels with possible statements: (always, often, periodically, rarely and never. The true answer is only one statement on one question. It is word about five degrees 'Likert's scale'. It was carried out extensive and complex statistics processing of date, where the input qualitative categorical variables were transformed into quantitative. In the next step, transformed categorical variables were exposed in classical and neoclassical statistical methodology. On the base of exact indications which were obtained by using relevant invariant and multivariate statistical methods and tests, dominant behavior style of coaches is 'Instructive'. This behavior style of coach is the most desirable. According to this researching at the last position is behavior style which is the autocratically and it is also at the same time the least desirable. The results of Analysis of variance (ANOVA and Canonic discriminative analysis show the general statistical significant difference in the representation of the behavior styles. Instructive and Autocratic behavior style of coach mostly influences on the total (general discrimination i.e. difference. For above mentioned styles, it could be said that they are paradigm of contrasts in every way. Values of Tukey - HSD test explicitly shows that there are not statistical significant difference between Instructive Style and style Awarded - Feedback as well as between Democratically and style of Social Support. The other combinations i.e. couples of behavior styles are statistical significantly different.

Electromagnetic Chirps from Neutron Star-Black Hole Mergers

Science.gov (United States)

Schnittman, Jeremy D.; Dal Canton, Tito; Camp, Jordan B.; Tsang, David; Kelly, Bernard J.

2018-01-01

We calculate the electromagnetic signal of a gamma-ray flare coming from the surface of a neutron star shortly before merger with a black hole companion. Using a new version of the Monte Carlo radiation transport code Pandurata that incorporates dynamic spacetimes, we integrate photon geodesics from the neutron star surface until they reach a distant observer or are captured by the black hole. The gamma-ray light curve is modulated by a number of relativistic effects, including Doppler beaming and gravitational lensing. Because the photons originate from the inspiraling neutron star, the light curve closely resembles the corresponding gravitational waveform: a chirp signal characterized by a steadily increasing frequency and amplitude. We propose to search for these electromagnetic chirps using matched filtering algorithms similar to those used in LIGO data analysis.

Microscopic origin of black hole reentrant phase transitions

Science.gov (United States)

Zangeneh, M. Kord; Dehyadegari, A.; Sheykhi, A.; Mann, R. B.

2018-04-01

Understanding the microscopic behavior of the black hole ingredients has been one of the important challenges in black hole physics during the past decades. In order to shed some light on the microscopic structure of black holes, in this paper, we explore a recently observed phenomenon for black holes namely reentrant phase transition, by employing the Ruppeiner geometry. Interestingly enough, we observe two properties for the phase behavior of small black holes that leads to reentrant phase transition. They are correlated and they are of the interaction type. For the range of pressure in which the system underlies reentrant phase transition, it transits from the large black holes phase to the small one which possesses higher correlation than the other ranges of pressures. On the other hand, the type of interaction between small black holes near the large/small transition line differs for usual and reentrant phase transitions. Indeed, for the usual case, the dominant interaction is repulsive whereas for the reentrant case we encounter an attractive interaction. We show that in the reentrant phase transition case, the small black holes behave like a bosonic gas whereas in the usual phase transition case, they behave like a quantum anyon gas.

Transformational Leadership Style as Predictor of Decision Making Styles: Moderating Role of Emotional Intelligence

OpenAIRE

Rana Rashid Rehman; Ajmal Waheed

2012-01-01

The current study examines the relationship among transformational leadership style and decision making styles. It also determines the moderating role of emotional intelligence in predicting this relationship. Three hypotheses are generated for the study i.e., twohypotheses are to measure the relationship among transformational leadership style and decision making styles whereas third hypothesis is to assess the moderating effect of emotional intelligence. Questionnaire method is used to coll...

DECISION-MAKING STYLES OF CONSUMERS IN TURKEY AND AZERBAIJAN: A CONSUMER STYLES INVENTORY APPROACH

OpenAIRE

ÖZDEMİR, Erkan; OMAROV, Zaur

2018-01-01

Consumersmake purchasing decisions based on different criteria. These criteria, whichcan be considered in many different titles such as price, quality, fashion,entertainment, also shape the purchasing decision-making styles of consumers. Consumerscan be divided into market segments according to decision-making styles. Thisstudy aims to determine the decision-making styles ofconsumers in Turkey and Azerbaijan and compare the decision-making styles ofconsumers in the two countries.The data coll...

Acceleration of particles by black holes: Kinematic explanation

International Nuclear Information System (INIS)

Zaslavskii, O. B.

2011-01-01

A new simple and general explanation of the effect of acceleration of particles by black holes to infinite energies in the center of mass frame is suggested. It is based on kinematics of particles moving near the horizon. This effect arises when particles of two kinds collide near the horizon. For massive particles, the first kind represents a particle with the generic energy and angular momentum (I call them ''usual''). Near the horizon, such a particle has a velocity almost equal to that of light in the frame that corotates with a black hole (the frame is static if a black hole is static). The second kind (called ''critical'') consists of particles with the velocity v< c near the horizon due to special relationship between the energy and angular momentum (or charge). As a result, the relative velocity approaches the speed of light c, and the Lorentz factor grows unbound. This explanation applies both to generic rotating black holes and charged ones (even for radial motion of particles). If one of the colliding particles is massless (photon), the critical particle is distinguished by the fact that its frequency is finite near the horizon. The existence (or absence) of the effect is determined depending on competition of two factors--gravitational blue shift for a photon propagating towards a black hole and the Doppler effect due to transformation from the locally nonrotating frame to a comoving one. Classification of all possible types of collisions is suggested depending on whether massive or massless particle is critical or usual.

Black carp (Mylopharyngodon piceus, Richardson. Thematic bibliography

Directory of Open Access Journals (Sweden)

I. Hrytsynyak

2017-03-01

Full Text Available Purpose. Creating a thematic bibliographic list of publications in Ukrainian and Russian, dedicated to the ecology, biology, selection and cultivation of such Far East fish fauna species as black carp (Mylopharyngodon piceus Richardson in conditions of fish farms of Ukraine and neighboring countries, as well as the possibility of it introduction into water bodies for bioameliorative purpose. Methodology. The complete and selective methods were applied in the process of the systematic search. The bibliographic core has been formed with the literature from the fund of the scientific library of the Institute of Fisheries NAAS. Findings. There was composed a thematic list of publications with a total quantity of 67 sources, containing characteristics of black carp as representative of cyprinids, which is very important species from the point of view of aquaculture. This bibliography covers the time period from 1949 till 2011.The literary sources were arranged in alphabetical order by author or title, and described according to DSTU 7.1:2006 «System of standards on information, librarianship and publishing. Bibliographic entry. Bibliographic description. General requirements and rules», as well as in accordance with the requirements of APA style — international standard of references. Practical value. The list may be useful for scientists, practitioners, students, whose area of interests covers the questions of breeding and study of the biological features of black carp.

Assessing Experiential Learning Styles: A Methodological Reconstruction and Validation of the Kolb Learning Style Inventory

Science.gov (United States)

Manolis, Chris; Burns, David J.; Assudani, Rashmi; Chinta, Ravi

2013-01-01

To understand experiential learning, many have reiterated the need to be able to identify students' learning styles. Kolb's Learning Style Model is the most widely accepted learning style model and has received a substantial amount of empirical support. Kolb's Learning Style Inventory (LSI), although one of the most widely utilized instruments to…

Nursing Students’ Preferred Learning Styles

Directory of Open Access Journals (Sweden)

Sh Salehi

2009-11-01

Full Text Available Background and purpose: Learning style is the processing of information and comprehension. If teachers present contents in a style that matches a student’s preferred learning style, academic performance and success will improve. If content retention improves it will result in an increase in thetest scores. It is also important to determine if students, as a group, fit into a particular style or a particular cycle as they move through an educational program.Methods: The study is a descriptive analytical research. Nursing Students at Isfahan Medical Sciences University completed a questionnaire  formulated to assess learning styles. Analysis of variance was used to investigate the possible relationship between learning cycle and student’s grades in the curriculum (i.e. freshman, sophomore, junior, or senior. Cross tabulation was used to test for a relationship between learning style and student academic year of study in the curriculum.Results: 294 students received the Kolb LSI questionnaire. The data demonstrated that juniors preferred a converger learning style and the senior students were in the abstract conceptualization cycle of learning. There were no relationships demonstrated between other groups in the study.Conclusion: The junior and senior students appear to prefer the stage of learning involving thinking and problem analysis. When a group of students demonstrate a preference for particular learning style teachers can develop their curriculum along their learning styleKey words: LEARNING STYLES, NURSING STUDENTS, FRESHMAN, SOPHOMORE, JUNIOR, SENIOR

Parenting styles, feeding styles and food-related parenting practices in relation to toddlers' eating styles: A cluster-analytic approach.

Science.gov (United States)

van der Horst, Klazine; Sleddens, Ester F C

2017-01-01

Toddlers' eating behaviors are influenced by the way parents interact with their children. The objective of this study was to explore how five major constructs of general parenting behavior cluster in parents of toddlers. These parenting clusters were further explored to see how they differed in the use of feeding strategies (i.e. feeding styles and food parenting practices) and by reported child eating styles. An online survey with 1005 mothers/caregivers (legal guardians) with at least one child between 12 and 36 months old was conducted in the United States in 2012, assessing general parenting behavior, feeding style, food parenting practices and the child eating styles. A three cluster solution of parenting style was found and clusters were labelled as overprotective/supervising, authoritarian, and authoritative. The clusters differed in terms of general parenting behaviors. Both overprotective and authoritative clusters showed high scores on structure, behavioral control, and nurturance. The overprotective cluster scored high on overprotection. The 'authoritarian' cluster showed lowest levels of nurturance, structure and behavioral control. Overprotective and authoritative parents showed very similar patterns in the use of food parenting practices, e.g. monitoring food intake, modeling, and promoting healthy food intake and availability at home. Overprotective parents also reported higher use of pressure to eat and involvement. Authoritarian parents reported high use of giving the child control over their food behaviors, emotion regulation, using food as a reward, and controlling food intake for weight control. Children's eating styles did not largely vary by parenting cluster. This study showed that a relatively new parenting style of overprotection is relevant for children's eating behaviors. Overprotective parents reported food parenting practices that are known to be beneficial for children's food intake, such as modelling healthy food intake, as well as

Parenting styles, feeding styles and food-related parenting practices in relation to toddlers' eating styles: A cluster-analytic approach.

Directory of Open Access Journals (Sweden)

Klazine van der Horst

Full Text Available Toddlers' eating behaviors are influenced by the way parents interact with their children. The objective of this study was to explore how five major constructs of general parenting behavior cluster in parents of toddlers. These parenting clusters were further explored to see how they differed in the use of feeding strategies (i.e. feeding styles and food parenting practices and by reported child eating styles.An online survey with 1005 mothers/caregivers (legal guardians with at least one child between 12 and 36 months old was conducted in the United States in 2012, assessing general parenting behavior, feeding style, food parenting practices and the child eating styles.A three cluster solution of parenting style was found and clusters were labelled as overprotective/supervising, authoritarian, and authoritative. The clusters differed in terms of general parenting behaviors. Both overprotective and authoritative clusters showed high scores on structure, behavioral control, and nurturance. The overprotective cluster scored high on overprotection. The 'authoritarian' cluster showed lowest levels of nurturance, structure and behavioral control. Overprotective and authoritative parents showed very similar patterns in the use of food parenting practices, e.g. monitoring food intake, modeling, and promoting healthy food intake and availability at home. Overprotective parents also reported higher use of pressure to eat and involvement. Authoritarian parents reported high use of giving the child control over their food behaviors, emotion regulation, using food as a reward, and controlling food intake for weight control. Children's eating styles did not largely vary by parenting cluster.This study showed that a relatively new parenting style of overprotection is relevant for children's eating behaviors. Overprotective parents reported food parenting practices that are known to be beneficial for children's food intake, such as modelling healthy food

Main: 1UHN [RPSD[Archive

Lifescience Database Archive (English)

Full Text Available ineered: Yes Metal Binding Protein M.Nagae, A.Nozawa, N.Koizumi, H.Sano, H.Hashimot...n 2 Name=Cbl2; Arabidopsis Thaliana Molecule: Calcineurin B-Like Protein 2; Chain: A; Fragment: Residues 32-220; Synonym: Atcbl2; Eng

NASA Observatory Confirms Black Hole Limits

Science.gov (United States)

2005-02-01

time, the ones in between have been counted properly. Growth of the Biggest Black Holes Illustrated Growth of the Biggest Black Holes Illustrated "We need to have an accurate head count over time of all growing black holes if we ever hope to understand their habits, so to speak," co-author Richard Mushotzky of NASA's Goddard Space Flight Center in Greenbelt, Md. Supermassive black holes themselves are invisible, but heated gas around them -- some of which will eventually fall into the black hole - produces copious amounts of radiation in the centers of galaxies as the black holes grow. Growth of the Biggest Black Holes Illustrated Growth of Smaller Black Holes Illustrated This study relied on the deepest X-ray images ever obtained, the Chandra Deep Fields North and South, plus a key wider-area survey of an area called the "Lockman Hole". The distances to the X-ray sources were determined by optical spectroscopic follow-up at the Keck 10-meter telescope on Mauna Kea in Hawaii, and show the black holes range from less than a billion to 12 billion light years away. Since X-rays can penetrate the gas and dust that block optical and ultraviolet emission, the very long-exposure X-ray images are crucial to find black holes that otherwise would go unnoticed. Black Hole Animation Black Hole Animation Chandra found that many of the black holes smaller than about 100 million Suns are buried under large amounts of dust and gas, which prevents detection of the optical light from the heated material near the black hole. The X-rays are more energetic and are able to burrow through this dust and gas. However, the largest of the black holes show little sign of obscuration by dust or gas. In a form of weight self-control, powerful winds generated by the black hole's feeding frenzy may have cleared out the remaining dust and gas. Other aspects of black hole growth were uncovered. For example, the typical size of the galaxies undergoing supermassive black hole formation reduces with

Citation Styles For Internet Resources : A Webliography

Directory of Open Access Journals (Sweden)

2004-12-01

Full Text Available A Webliography collects resources about citation Styles For internet resources, it divided by the styles: Chicago University style, MLA style, APA style, ISO style, and some articles about internet resources citation.

The Generic Style Rules for Linguistics

OpenAIRE

Haspelmath, Martin

2014-01-01

The Generic Style Rules for Linguistics provide a style sheet that can be used by any linguistics journal or edited book, or for teaching purposes. They regulate aspects of text-structure style such as typographic highlighting, citation style, use of capitalization, and bibliographic style (based on the LSA's Unified Stylesheet for linguistics).

Boreal Tree Light- and Water-Use: Asynchronous, Diverging, yet Complementary

Science.gov (United States)

Pappas, C.; Baltzer, J. L.; Barr, A.; Black, T. A.; Bohrer, G.; Detto, M.; Maillet, J.; Matheny, A. M.; Roy, A.; Sonnentag, O.; Stephens, J.

2017-12-01

Water stress has been suggested as a key mechanism behind the contemporary increase in tree mortality rates in northwestern North America. However, a detailed analysis of boreal tree light- and water-use strategies as well as their interspecific differences are still lacking. Here, we examine the tree hydraulic behaviour of co-occurring larch (Larix laricina) and black spruce (Picea mariana), two characteristic boreal tree species, near the southern limit of the boreal ecozone in central Canada. Sap flux density (Js) and concurrently recorded stem radius fluctuations and meteorological conditions are used to quantify tree hydraulic functioning and to scrutinize tree light- and water-use strategies. Our analysis reveals an asynchrony in the diel hydrodynamics of the two species with the initial rise in Js occurring two hours earlier in larch than in black spruce. Structural differences in the crown architecture of larch and black spruce lead to interspecific differences in light harvesting that can explain the observed asynchrony in their hydraulic function. Furthermore, the two species exhibit diverging stomatal regulation strategies with larch employing relatively isohydric whereas black spruce anisohydric behaviour. Such asynchronous and diverging tree-level light- and water-use strategies provide new insights into the ecosystem-level complementarity of tree form and function, with implications for understanding boreal forests' water and carbon dynamics and resilience to environmental stress.

Strong field gravitational lensing by a charged Galileon black hole

Energy Technology Data Exchange (ETDEWEB)

Zhao, Shan-Shan; Xie, Yi, E-mail: clefairy035@163.com, E-mail: yixie@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

2016-07-01

Strong field gravitational lensings are dramatically disparate from those in the weak field by representing relativistic images due to light winds one to infinity loops around a lens before escaping. We study such a lensing caused by a charged Galileon black hole, which is expected to have possibility to evade no-hair theorem. We calculate the angular separations and time delays between different relativistic images of the charged Galileon black hole. All these observables can potentially be used to discriminate a charged Galileon black hole from others. We estimate the magnitudes of these observables for the closest supermassive black hole Sgr A*. The strong field lensing observables of the charged Galileon black hole can be close to those of a tidal Reissner-Nordström black hole or those of a Reissner-Nordström black hole. It will be helpful to distinguish these black holes if we can separate the outermost relativistic images and determine their angular separation, brightness difference and time delay, although it requires techniques beyond the current limit.

Evaluating Style Analysis

NARCIS (Netherlands)

F.A. de Roon (Frans); T.E. Nijman (Theo); B.J.M. Werker

2000-01-01

textabstractIn this paper we evaluate applications of (return based) style analysis. The portfolio and positivity constraints imposed by style analysis are useful in constructing mimicking portfolios without short positions. Such mimicking portfolios can be used e.g. to construct efficient

The light up and early evolution of high redshift Supermassive Black Holes

Science.gov (United States)

Comastri, Andrea; Brusa, Marcella; Aird, James; Lanzuisi, Giorgio

2016-07-01

The known AGN population at z > 6 is made by luminous optical QSO hosting Supermassive Black Holes (M > 10 ^{9}solar masses), likely to represent the tip of the iceberg of the luminosity and mass function. According to theoretical models for structure formation, Massive Black Holes (M _{BH} 10^{4-7} solar masses) are predicted to be abundant in the early Universe (z > 6). The majority of these lower luminosity objects are expected to be obscured and severely underepresented in current optical near-infrared surveys. The detection of such a population would provide unique constraints on the Massive Black Holes formation mechanism and subsequent growth and is within the capabilities of deep and large area ATHENA surveys. After a summary of the state of the art of present deep XMM and Chandra surveys, at z >3-6 also mentioning the expectations for the forthcoming eROSITA all sky survey; I will present the observational strategy of future multi-cone ATHENA Wide Field Imager (WFI) surveys and the expected breakthroughs in the determination of the luminosity function and its evolution at high (> 4) and very high (>6) redshifts.

ONE-DIMENSIONAL AND TWO-DIMENSIONAL LEADERSHIP STYLES

Directory of Open Access Journals (Sweden)

Nikola Stefanović

2007-06-01

Full Text Available In order to motivate their group members to perform certain tasks, leaders use different leadership styles. These styles are based on leaders' backgrounds, knowledge, values, experiences, and expectations. The one-dimensional styles, used by many world leaders, are autocratic and democratic styles. These styles lie on the two opposite sides of the leadership spectrum. In order to precisely define the leadership styles on the spectrum between the autocratic leadership style and the democratic leadership style, leadership theory researchers use two dimensional matrices. The two-dimensional matrices define leadership styles on the basis of different parameters. By using these parameters, one can identify two-dimensional styles.

Surprise: Dwarf Galaxy Harbors Supermassive Black Hole

Science.gov (United States)

2011-01-01

The surprising discovery of a supermassive black hole in a small nearby galaxy has given astronomers a tantalizing look at how black holes and galaxies may have grown in the early history of the Universe. Finding a black hole a million times more massive than the Sun in a star-forming dwarf galaxy is a strong indication that supermassive black holes formed before the buildup of galaxies, the astronomers said. The galaxy, called Henize 2-10, 30 million light-years from Earth, has been studied for years, and is forming stars very rapidly. Irregularly shaped and about 3,000 light-years across (compared to 100,000 for our own Milky Way), it resembles what scientists think were some of the first galaxies to form in the early Universe. "This galaxy gives us important clues about a very early phase of galaxy evolution that has not been observed before," said Amy Reines, a Ph.D. candidate at the University of Virginia. Supermassive black holes lie at the cores of all "full-sized" galaxies. In the nearby Universe, there is a direct relationship -- a constant ratio -- between the masses of the black holes and that of the central "bulges" of the galaxies, leading them to conclude that the black holes and bulges affected each others' growth. Two years ago, an international team of astronomers found that black holes in young galaxies in the early Universe were more massive than this ratio would indicate. This, they said, was strong evidence that black holes developed before their surrounding galaxies. "Now, we have found a dwarf galaxy with no bulge at all, yet it has a supermassive black hole. This greatly strengthens the case for the black holes developing first, before the galaxy's bulge is formed," Reines said. Reines, along with Gregory Sivakoff and Kelsey Johnson of the University of Virginia and the National Radio Astronomy Observatory (NRAO), and Crystal Brogan of the NRAO, observed Henize 2-10 with the National Science Foundation's Very Large Array radio telescope and

Styling Hawai'i in "Haole"wood: White Protagonists on a Voyage of Self Discovery

Science.gov (United States)

Higgins, Christina; Furukawa, Gavin

2012-01-01

This article analyzes four Hollywood films set in Hawai'i to shed light on how particular languages and language varieties "style" (Auer 2007; Coupland 2007) Local/Hawaiian and mainland U.S. characters as certain kinds of people. Through an analysis of films featuring "haole" ("white, outsider") male protagonists who…

Parenting style and adolescent smoking.

Science.gov (United States)

O'Byrne, Kristin Koetting; Haddock, C Keith; Poston, Walker S C

2002-06-01

To investigate whether parenting style is an independent risk factor of smoking initiation and experimentation among adolescents, and whether there is a relationship between parenting style and readiness to quit, or nicotine dependence among smokers. The 84-item Health and Smoking Questionnaire, which assesses demographics, smoking status and smoking history, perceptions of risk and risk reduction, risk factors for tobacco use, and parenting style, was administered to 816 adolescents in grades 7 to 12 (mean age, 15.1 years) of whom 22.6% (n = 182) were smokers. Parenting style was measured by the brief, non-retrospective version of the Family of Origin Scale (FOS). Higher scores on the FOS indicated more positive perceived parenting style with high levels of intimacy and autonomy, characteristics of healthy parent-child relationships. Data were analyzed using a model-building approach to logistic regression with demographic and other psychosocial variables in the first two steps, and with parenting style as the last step. Results from two logistic regression models indicate that although parenting style is not a significant risk factor for smoking experimentation [odds ratio (OR) =.998; confidence interval (CI) =.977-1.019; p =.820], it is a significant independent risk factor for smoking initiation (OR =.950; CI =.930-.970; p =.000). Smokers who were more ready to quit had higher parenting style scores than those who were not ready to quit, and smokers who had made a serious quit attempt (an indicator of nicotine addiction) had higher parenting style scores than those who had not made a quit attempt. Moreover, nonsmokers who reported they would smoke a cigarette if their best friend offered had significantly lower parenting style scores than those who reported they would not smoke a cigarette. Additional research on parenting style and its impact on adolescent smoking with a more economically and ethnically diverse sample is warranted. If future research confirms

BOOK REVIEW: Introduction to Black Hole Physics Introduction to Black Hole Physics

Science.gov (United States)

Tanaka, Takahiro

2012-07-01

expected in the near future. Such hot topics are presented in Section 10: 'Black Holes and All That Jazz'. I would also consider the historical overview of the research on black holes given in Section 1 to be very interesting. Overall, I strongly recognised the intention of the authors not to go into too much detail; in this sense, I would say that the book has the aspect of a showcase of the frontiers of black hole physics. There are many topics which are very interesting but mathematically a little complicated; however, those subjects are appropriately treated so that the reader will not be overloaded with mathematical complexity. For example, in the discussion of black hole perturbation, only scalar field perturbation is discussed. The authors might have discussed gravitational wave perturbation, but this is much more complicated and the essential physics is mostly included in the simplest example of the scalar field. If I were one of the authors, I would consider adding more detailed explanations about several such advanced topics. However, the authors well know that such a challenge just presents a barrier to young students who are going to read this book, and really it is only an introduction to this interesting research field. This style might be the result of the long experience from the lectures over 30 years: the explanations of the subjects that the authors describe in detail are very carefully presented, avoiding logical gaps. In the preface, the authors state that they tried hard to answer students' questions as much as possible; I think that the authors' method in this respect is very successful.

Evaluating Style Analysis

NARCIS (Netherlands)

de Roon, F.A.; Nijman, T.E.; Ter Horst, J.R.

2000-01-01

In this paper we evaluate applications of (return based) style analysis.The portfolio and positivity constraints imposed by style analysis are useful in constructing mimicking portfolios without short positions.Such mimicking portfolios can be used, e.g., to construct efficient portfolios of mutual

An Examination of Elementary School Students' Parental Style and Parental Internet Style with Respect to Various Variables

OpenAIRE

Deniz, Metin; Horzum, Mehmet Barış; Ayas, Tuncay; Koç, Mustafa

2016-01-01

Abstract: The aim of this study is to determine the relationship between parental style and internet parental style and find out whether student's parental style and parental internet style differ according to various variables. In this study, survey model was used. The study was performed with 296 students, attending at an elementary school in the second period of 2011-2012 academic years in Sakarya, Turkey. Parental style and parental internet style scales were used. Results indicated ...

Le Paris d’Hemingway : une question de style

OpenAIRE

Mallier, Clara

2017-01-01

Hemingway’s representation of Paris in The Sun Also Rises and A Moveable Feast has held many a reader in thrall. It steers clear of traditional description as the author prefers to "make" the city rather than "describe" it. This article analyzes Hemingway’s style in the light of this enigmatic aesthetic statement. The author’s idiosyncratic syntax tends to blur the semantic frontiers between juxtaposed words, and his use of repetition enhances the musicality of sentences, which constitutes th...

Low surface damage dry etched black silicon

DEFF Research Database (Denmark)

Plakhotnyuk, Maksym M.; Gaudig, Maria; Davidsen, Rasmus Schmidt

2017-01-01

Black silicon (bSi) is promising for integration into silicon solar cell fabrication flow due to its excellent light trapping and low reflectance, and a continuously improving passivation. However, intensive ion bombardment during the reactive ion etching used to fabricate bSi induces surface dam...

Modelling plastic scintillator response to gamma rays using light transport incorporated FLUKA code

Energy Technology Data Exchange (ETDEWEB)

Ranjbar Kohan, M. [Physics Department, Tafresh University, Tafresh (Iran, Islamic Republic of); Etaati, G.R. [Department of Nuclear Engineering and Physics, Amir Kabir University of Technology, Tehran (Iran, Islamic Republic of); Ghal-Eh, N., E-mail: ghal-eh@du.ac.ir [School of Physics, Damghan University, Damghan (Iran, Islamic Republic of); Safari, M.J. [Department of Energy Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Afarideh, H. [Department of Nuclear Engineering and Physics, Amir Kabir University of Technology, Tehran (Iran, Islamic Republic of); Asadi, E. [Department of Physics, Payam-e-Noor University, Tehran (Iran, Islamic Republic of)

2012-05-15

The response function of NE102 plastic scintillator to gamma rays has been simulated using a joint FLUKA+PHOTRACK Monte Carlo code. The multi-purpose particle transport code, FLUKA, has been responsible for gamma transport whilst the light transport code, PHOTRACK, has simulated the transport of scintillation photons through scintillator and lightguide. The simulation results of plastic scintillator with/without light guides of different surface coverings have been successfully verified with experiments. - Highlights: Black-Right-Pointing-Pointer A multi-purpose code (FLUKA) and a light transport code (PHOTRACK) have been linked. Black-Right-Pointing-Pointer The hybrid code has been used to generate the response function of an NE102 scintillator. Black-Right-Pointing-Pointer The simulated response functions exhibit a good agreement with experimental data.

AUTOMATIC ARCHITECTURAL STYLE RECOGNITION

Directory of Open Access Journals (Sweden)

M. Mathias

2012-09-01

Full Text Available Procedural modeling has proven to be a very valuable tool in the field of architecture. In the last few years, research has soared to automatically create procedural models from images. However, current algorithms for this process of inverse procedural modeling rely on the assumption that the building style is known. So far, the determination of the building style has remained a manual task. In this paper, we propose an algorithm which automates this process through classification of architectural styles from facade images. Our classifier first identifies the images containing buildings, then separates individual facades within an image and determines the building style. This information could then be used to initialize the building reconstruction process. We have trained our classifier to distinguish between several distinct architectural styles, namely Flemish Renaissance, Haussmannian and Neoclassical. Finally, we demonstrate our approach on various street-side images.

Dance of Two Monster Black Holes

Science.gov (United States)

Kohler, Susanna

2016-03-01

This past December, researchers all over the world watched an outburst from the enormous black hole in OJ 287 an outburst that had been predicted years ago using the general theory of relativity.Outbursts from Black-Hole OrbitsOJ 287 is one of the largest supermassive black holes known, weighing in at 18 billion solar masses. Located about 3.5 billion light-years away, this monster quasar is bright enough that it was first observed as early as the 1890s. What makes OJ 287 especially interesting, however, is that its light curve exhibits prominent outbursts roughly every 12 years.Diagram illustrating the orbit of the secondary black hole (shown in blue) in OJ 287 from 2000 to 2023. We see outbursts (the yellow bubbles) every time the secondary black hole crosses the accretion disk (shown in red, ina side view) surrounding the primary (the black circle). [Valtonen et al. 2016]What causes the outbursts? Astronomers think that there is a second supermassive black hole, ~100 times smaller, inspiraling as it orbits the central monster and set to merge within the next 10,000 years. In this model, the primary black hole of OJ 287 is surrounded by a hot accretion disk. As the secondary black hole orbits the primary, it regularly punches through this accretion disk, heating the material and causing the release of expanding bubbles of hot gas pulled from the disk. This gas then radiates thermally, causing the outbursts we see.Attempts to model this scenario using Newtonian orbits all fail; the timing of the secondary black holes crossings through the accretion disk (as measured by when we see the outbursts) can only be explained by a model incorporating general-relativistic effects on the orbit. Careful observations and precise timing of these outbursts therefore provide an excellent test of general relativity.Watching a Predicted CrossingThe model of OJ 287 predicted another disk crossing in December 2015, so professional and amateur astronomers around the world readied more

Adjustable liquid aperture to eliminate undesirable light in holographic projection.

Science.gov (United States)

Wang, Di; Liu, Chao; Li, Lei; Zhou, Xin; Wang, Qiong-Hua

2016-02-08

In this paper, we propose an adjustable liquid aperture to eliminate the undesirable light in a holographic projection. The aperture is based on hydrodynamic actuation. A chamber is formed with a cylindrical tube. A black droplet is filled in the sidewall of the cylinder tube and the outside space is the transparent oil which is immiscible with the black droplet. An ultrathin glass sheet is attached on the bottom substrate of the device and a black shading film is secured to the central area of the glass sheet. By changing the volume of the black droplet, the black droplet will move to the middle or sidewall due to hydrodynamic actuation, so the device can be used as an adjustable aperture. A divergent spherical wave and a solid lens are used to separate the focus planes of the reconstructed image and diffraction beams induced by the liquid crystal on silicon in the holographic projection. Then the aperture is used to eliminate the diffraction beams by adjusting the size of the liquid aperture and the holographic projection does not have undesirable light.

Radiation transport around Kerr black holes

Science.gov (United States)

Schnittman, Jeremy David

This Thesis describes the basic framework of a relativistic ray-tracing code for analyzing accretion processes around Kerr black holes. We begin in Chapter 1 with a brief historical summary of the major advances in black hole astrophysics over the past few decades. In Chapter 2 we present a detailed description of the ray-tracing code, which can be used to calculate the transfer function between the plane of the accretion disk and the detector plane, an important tool for modeling relativistically broadened emission lines. Observations from the Rossi X-Ray Timing Explorer have shown the existence of high frequency quasi-periodic oscillations (HFQPOs) in a number of black hole binary systems. In Chapter 3, we employ a simple "hot spot" model to explain the position and amplitude of these HFQPO peaks. The power spectrum of the periodic X-ray light curve consists of multiple peaks located at integral combinations of the black hole coordinate frequencies, with the relative amplitude of each peak determined by the orbital inclination, eccentricity, and hot spot arc length. In Chapter 4, we introduce additional features to the model to explain the broadening of the QPO peaks as well as the damping of higher frequency harmonics in the power spectrum. The complete model is used to fit the power spectra observed in XTE J1550-564, giving confidence limits on each of the model parameters. In Chapter 5 we present a description of the structure of a relativistic alpha- disk around a Kerr black hole. Given the surface temperature of the disk, the observed spectrum is calculated using the transfer function mentioned above. The features of this modified thermal spectrum may be used to infer the physical properties of the accretion disk and the central black hole. In Chapter 6 we develop a Monte Carlo code to calculate the detailed propagation of photons from a hot spot emitter scattering through a corona surrounding the black hole. The coronal scattering has two major observable

Learning-style preferences of Latino/Hispanic community college students enrolled in an introductory biology course

Science.gov (United States)

Sarantopoulos, Helen D.

Purpose. The purpose of this study was to identify, according to the Productivity Environment Preference Survey (PEPS) instrument, which learning-style domains (environmental, emotional, sociological, and physiological) were favored among Latino/Hispanic community college students enrolled in introductory biology classes in a large, urban community college. An additional purpose of this study was to determine whether statistically significant differences existed between the learning-style preferences and the demographic variables of age, gender, number of prior science courses, second language learner status, and earlier exposure to scientific information. Methodology. The study design was descriptive and ex post facto. The sample consisted of a total of 332 Latino/Hispanic students enrolled in General Biology 3. Major findings. The study revealed that Latino/Hispanic students enrolled in introductory biology at a large urban community college scored higher for the learning preference element of structure. Students twenty-five years and older scored higher for the learning preference elements of light, design, persistence, responsibility, and morning time (p learning-style preferences were found between second English language learners and those who learned English as their primary language (p tactile (p learning-style model and instruments and on recent learning-style research articles on ethnically diverse groups of adult learners; and (2) Instructors should plan their instruction to incorporate the learning-style preferences of their students.

Mass inflation inside black holes revisited

International Nuclear Information System (INIS)

Dokuchaev, Vyacheslav I

2014-01-01

The mass inflation phenomenon implies that black hole interiors are unstable due to a back-reaction divergence of the perturbed black hole mass function at the Cauchy horizon. The mass inflation was initially derived by using the generalized Dray–’t Hooft–Redmount (DTR) relation in the linear approximation of the Einstein equations near the perturbed Cauchy horizon of the Reissner–Nordström black hole. However, this linear approximation for the DTR relation is improper for the highly nonlinear behavior of back-reaction perturbations at the black hole horizons. An additional weak point in the standard mass inflation calculations is in a fallacious using of the global Cauchy horizon as a place for the maximal growth of the back-reaction perturbations instead of the local inner apparent horizon. It is derived the new spherically symmetric back-reaction solution for two counter-streaming light-like fluxes near the inner apparent horizon of the charged black hole by taking into account its separation from the Cauchy horizon. In this solution the back-reaction perturbations of the background metric are truly the largest at the inner apparent horizon, but, nevertheless, remain small. The back reaction, additionally, removes the infinite blue-shift singularity at the inner apparent horizon and at the Cauchy horizon. (paper)

The mediational pathway among parenting styles, attachment styles and self-regulation with addiction susceptibility of adolescents.

Science.gov (United States)

Zeinali, Ali; Sharifi, Hassanpasha; Enayati, Mirsalahadine; Asgari, Parviz; Pasha, Gohlamreza

2011-09-01

The purpose of present study was to create and test a model that illustrates variables that influence the development of addiction susceptibility and determine how different styles of parenting may indirectly influence the addiction susceptibility of children through the mediators of attachment style and self-regulation. Using random cluster sampling, 508 adolescent high school boys and girls aged 14-19 years were enrolled. Data were analyzed using structural equations modeling (path analysis). The results showed that authoritative and permissive parenting styles were associated with secure attachment whereas authoritarian and neglectful parenting styles were associated with insecure attachment. Insecure attachment was associated with a low level of self-regulation whereas secure attachment was associated with a high level of self-regulation. We found that a low level of self-regulation increased the adolescent's addiction susceptibility whereas a high level of self-regulation decreased their addiction susceptibility. The findings of present study suggest the authoritative and permissive parenting styles as the most efficient styles and authoritarian and neglectful parenting styles as the most inefficient styles in terms of addiction susceptibility. Accordingly, efficient parenting style training to parents should be the main goal of drug demand reduction program.

Theoretical Frontiers in Black Holes and Cosmology School

CERN Document Server

Orazi, Emanuele

2016-01-01

These lecture notes are dedicated to the most recent theoretical applications of Black Hole solutions in high-energy physics. The main motivation of this volume is to present the latest black hole backgrounds that are relevant for gauge/gravity correspondence. Leading scientists in the field explain effective techniques for finding singular and cosmological solutions embedded in gauged supergravity, shedding light on underlying properties and symmetries. Starting from a basic level, the mathematical structures underlying black holes and cosmologies are revealed, helping the reader grasp the connection between theoretical approaches and physical observations with insights into possible future developments from both a theoretical and experimental point of view. The topics covered in this volume are based on lectures delivered during the “Theoretical Frontiers in Black Holes and Cosmology” school, held in Natal in June 2015.

A Facile Approach to Prepare Black TiO2 with Oxygen Vacancy for Enhancing Photocatalytic Activity

Science.gov (United States)

Chen, Shihao; Xiao, Yang; Hu, Zhengfa; Zhao, Hui; Xie, Wei

2018-01-01

Black TiO2 has triggered worldwide research interest due to its excellent photocatalytic properties. However, the understanding of its structure–property relationships and a more effective, facile and versatile method to produce it remain great challenges. We have developed a facile approach to synthesize black TiO2 nanoparticles with significantly improved light absorption in the visible and infrared regions. The experimental results show that oxygen vacancies are the major factors responsible for black coloration. More importantly, our black TiO2 nanoparticles have no Ti3+ ions. These oxygen vacancies could introduce localized states in the bandgap and act as trap centers, significantly decreasing the electron–hole recombination. The photocatalytic decomposition of both rhodamine B and methylene blue demonstrated that, under ultraviolet light irradiation, better photocatalytic performance is achieved with our black TiO2 nanoparticles than with commercial TiO2 nanoparticles. PMID:29659500

A Reinforcement Model of the Relationships of Supervisors' General Communication Styles and Conflict Management Styles to Task Attraction.

Science.gov (United States)

Wheeless, Lawrence R.; Reichel, Lisa S.

1990-01-01

Investigates the relationship between general styles of communicating and more situation-specific conflict management styles. Finds substantial relationships between general communication styles and conflict management styles, as well as very substantial relationships between the style constructs and task attraction of supervisors. (SR)

Different Styles for Different Needs – The Effect of Cognitive Styles on Idea Generation

DEFF Research Database (Denmark)

Lomberg, Carina; Kollmann, Tobias; Stockmann, Christoph

2017-01-01

Researchers are engaged in finding the precursors for innovation. Drawing on Kirton's Adaption-Innovation (KAI) Inventory, we explicitly test Kirton's central premise that cognitive styles differentiate between preferences for producing ideas in a certain way. We argue that the generation of either...... a magnitude or original ideas is governed by different underlying cognitive styles. In a study with 191 individuals, we find that the cognitive style originality associates with ideational fluency whereas the rule governance style associates with the generation of original ideas. By providing a cognitive...

Parenting styles, feeding styles and food-related parenting practices in relation to toddlers’ eating styles: A cluster-analytic approach

Science.gov (United States)

Sleddens, Ester F. C.

2017-01-01

Introduction Toddlers’ eating behaviors are influenced by the way parents interact with their children. The objective of this study was to explore how five major constructs of general parenting behavior cluster in parents of toddlers. These parenting clusters were further explored to see how they differed in the use of feeding strategies (i.e. feeding styles and food parenting practices) and by reported child eating styles. Methods An online survey with 1005 mothers/caregivers (legal guardians) with at least one child between 12 and 36 months old was conducted in the United States in 2012, assessing general parenting behavior, feeding style, food parenting practices and the child eating styles. Results A three cluster solution of parenting style was found and clusters were labelled as overprotective/supervising, authoritarian, and authoritative. The clusters differed in terms of general parenting behaviors. Both overprotective and authoritative clusters showed high scores on structure, behavioral control, and nurturance. The overprotective cluster scored high on overprotection. The ‘authoritarian’ cluster showed lowest levels of nurturance, structure and behavioral control. Overprotective and authoritative parents showed very similar patterns in the use of food parenting practices, e.g. monitoring food intake, modeling, and promoting healthy food intake and availability at home. Overprotective parents also reported higher use of pressure to eat and involvement. Authoritarian parents reported high use of giving the child control over their food behaviors, emotion regulation, using food as a reward, and controlling food intake for weight control. Children’s eating styles did not largely vary by parenting cluster. Conclusion This study showed that a relatively new parenting style of overprotection is relevant for children’s eating behaviors. Overprotective parents reported food parenting practices that are known to be beneficial for children’s food intake

The impact of group training about parenting styles on maternal attitudes toward parenting styles.

Science.gov (United States)

Zandiyeh, Zahra; Zare, Elaheh; Hedayati, Batool

2015-01-01

Parenting style is one of the most important and effective factors in training and growth of children and adolescents and the method that parents communicate with their children is an effective factor on family contact models. The aim of this study was to determine the impact of group training about parenting styles on maternal attitudes that were admitted to Isfahan Imam Ali (AS) health care center in 2013. This was an experimental study, which was conducted on a random sample of 25 mothers referred to this health care center. They were divided into two groups (experimental and control). The experimental group received five sessions of group training, and the control group received a booklet about parenting styles. The used tool in this study was the Bamerind Parenting Style Questionnaire that was completed by the mothers before and after the intervention and finally, their obtained scores were compared with each other. The results of the present study showed that the mean score of attitude toward easy-going style in test group was less than the control group after intervention (P = 0.045). The mean score of attitude toward authoritative style in the experimental group was less than control group after intervention (P = 0.037) and the mean score of attitude toward authoritative style in the experimental group was more than the control group after intervention (P = 0.011). Group training can be an appropriate method in changing maternal attitudes toward parenting styles.

Styles and Style-Stretching: How Are They Related to Successful Learning?

Science.gov (United States)

Griffiths, Carol; Inceçay, Görsev

2016-01-01

Although the learning style construct has aroused much interest over the years, questions remain regarding basic issues such as definition, the validity and/or reliability of various measurement instruments, and the relationship between learning style and successful learning. Furthermore, although maintaining stylistic flexibility is recommended…

Leadership styles and theories.

Science.gov (United States)

Giltinane, Charlotte Louise

It is useful for healthcare professionals to be able to identify the leadership styles and theories relevant to their nursing practice. Being adept in recognising these styles enables nurses to develop their skills to become better leaders, as well as improving relationships with colleagues and other leaders, who have previously been challenging to work with. This article explores different leadership styles and theories, and explains how they relate to nursing practice.

ONE-DIMENSIONAL AND TWO-DIMENSIONAL LEADERSHIP STYLES

OpenAIRE

Nikola Stefanović

2007-01-01

In order to motivate their group members to perform certain tasks, leaders use different leadership styles. These styles are based on leaders' backgrounds, knowledge, values, experiences, and expectations. The one-dimensional styles, used by many world leaders, are autocratic and democratic styles. These styles lie on the two opposite sides of the leadership spectrum. In order to precisely define the leadership styles on the spectrum between the autocratic leadership style and the democratic ...

Light pollution, reproductive function and cancer risk.

Science.gov (United States)

Anisimov, Vladimir N

2006-01-01

At present, light pollution (exposure to light-at-night) both in the form of occupational exposure during night work and as a personal choice and life style, is experienced by numerous night-active members of our society. Disruption of the circadian rhythms induced by light pollution has been associated with cancer in humans. There are epidemiological evidences of increased breast and colon cancer risk in shift workers. An inhibition of the pineal gland function with exposure to the constant light (LL) regimen promoted carcinogenesis whereas the light deprivation inhibits the carcinogenesis. Treatment with pineal indole hormone melatonin inhibits carcinogenesis in pinealectomized rats or animals kept at the standard light/dark regimen (LD) or at the LL regimen. These observations might lead to use melatonin for cancer prevention in groups of humans at risk of light pollution.

The effects of additional black carbon on Arctic sea ice surface albedo: variation with sea ice type and snow cover

OpenAIRE

A. A. Marks; M. D. King

2013-01-01

Black carbon in sea ice will decrease sea ice surface albedo through increased absorption of incident solar radiation, exacerbating sea ice melting. Previous literature has reported different albedo responses to additions of black carbon in sea ice and has not considered how a snow cover may mitigate the effect of black carbon in sea ice. Sea ice is predominately snow covered. Visible light absorption and light scattering coefficients are calculated for a typical first year and multi-y...

Some Simple Black Hole Thermodynamics

Science.gov (United States)

Lopresto, Michael C.

2003-05-01

In his recent popular book The Universe in a Nutshell, Steven Hawking gives expressions for the entropy1 and temperature (often referred to as the ``Hawking temperature''2 ) of a black hole:3 S = kc34ℏG A T = ℏc38πkGM, where A is the area of the event horizon, M is the mass, k is Boltzmann's constant, ℏ = h2π (h being Planck's constant), c is the speed of light, and G is the universal gravitational constant. These expressions can be used as starting points for some interesting approximations on the thermodynamics of a Schwarzschild black hole, of mass M, which by definition is nonrotating and spherical with an event horizon of radius R = 2GMc2.4,5

Teaching for Different Learning Styles.

Science.gov (United States)

Cropper, Carolyn

1994-01-01

This study examined learning styles in 137 high ability fourth-grade students. All students were administered two learning styles inventories. Characteristics of students with the following learning styles are summarized: auditory language, visual language, auditory numerical, visual numerical, tactile concrete, individual learning, group…

Cognitive Styles and Distance Education.

Science.gov (United States)

Liu, Yuliang; Ginther, Dean

1999-01-01

Considers how to adapt the design of distance education to students' cognitive styles. Discusses cognitive styles, including field dependence versus independence, holistic-analytic, sensory preference, hemispheric preferences, and Kolb's Learning Style Model; and the characteristics of distance education, including technology. (Contains 92…

Influence of near-ultraviolet light enhancement and photosynthetic photon flux density during photoperiod extension on the morphology and lignin content of black spruce seedlings

International Nuclear Information System (INIS)

Margolis, H.; Vezina, L.P.; Bellefleur, P.

1991-01-01

When containerized black spruce seedlings (Picea mariana (Mill.) B.S.P.) are grown rapidly in greenhouse culture, they sometimes bend over, grow horizontally and become deformed. This phenomenon has been known to affect between 5% and 10% of a winter greenhouse crop. In this study, near-ultraviolet lamps were used to supplement the artificial light received from high-pressure sodium lamps and the effects on seedling morphology and lignin contents were examined. Neither height to diameter ratios nor lignin concentrations were significantly affected by UV radiation flux density. However, seedling biomass, height, root collar diameter, lignin content, and lignin to cellulose ratios of stems were significantly correlated with total photosynthetic photon flux density (PPFD) received during photoperiod extension. Height to diameter ratios were negatively correlated with PPFD during photoperiod enhancement because of a greater relative increase in diameter growth compared with height growth. Neither UV nor PAR flux density affected the percentage of black spruce seedlings having stem deformations greater than 30 ° from the vertical [fr

The mediational pathway among parenting styles, attachment styles and self-regulation with addiction susceptibility of adolescents*

Science.gov (United States)

Zeinali, Ali; Sharifi, Hassanpasha; Enayati, Mirsalahadine; Asgari, Parviz; Pasha, Gohlamreza

2011-01-01

BACKGROUND: The purpose of present study was to create and test a model that illustrates variables that influence the development of addiction susceptibility and determine how different styles of parenting may indirectly influence the addiction susceptibility of children through the mediators of attachment style and self-regulation. METHODS: Using random cluster sampling, 508 adolescent high school boys and girls aged 14-19 years were enrolled. Data were analyzed using structural equations modeling (path analysis). RESULTS: The results showed that authoritative and permissive parenting styles were associated with secure attachment whereas authoritarian and neglectful parenting styles were associated with insecure attachment. Insecure attachment was associated with a low level of self-regulation whereas secure attachment was associated with a high level of self-regulation. We found that a low level of self-regulation increased the adolescent's addiction susceptibility whereas a high level of self-regulation decreased their addiction susceptibility. CONCLUSIONS: The findings of present study suggest the authoritative and permissive parenting styles as the most efficient styles and authoritarian and neglectful parenting styles as the most inefficient styles in terms of addiction susceptibility. Accordingly, efficient parenting style training to parents should be the main goal of drug demand reduction program. PMID:22973379

Exploring Perspectives of Transitional Leadership Styles at Historically Black Colleges and Universities: A Case Study

Science.gov (United States)

Mosley, Melvin L.

2017-01-01

Historically Black Colleges and Universities (HBCUs) continue to strive for academic relevance in spite of the national problem of the misalignment of mission and values among their institutional leadership. The national problem was important to both the HBCU institutions and the entire academic community to establish global relevancy. The…

Identity Styles and Conflict Resolution Styles: Associations in Mother-Adolescent Dyads

Science.gov (United States)

Missotten, Lies Christine; Luyckx, Koen; Branje, Susan; Vanhalst, Janne; Goossens, Luc

2011-01-01

Adolescent identity and parent-adolescent conflict have each attracted considerable research interest. However, few studies have examined the important link between the two constructs. The present study examined the associations between adolescent identity processing styles and adolescent conflict resolution styles in the mother-adolescent dyad.…

Characteristics of black carbon emissions from in-use light-duty passenger vehicles.

Science.gov (United States)

Zheng, Xuan; Zhang, Shaojun; Wu, Ye; Zhang, K Max; Wu, Xian; Li, Zhenhua; Hao, Jiming

2017-12-01

Mitigating black carbon (BC) emissions from various combustion sources has been considered an urgent policy issue to address the challenges of climate change, air pollution and health risks. Vehicles contribute considerably to total anthropogenic BC emissions and urban BC concentrations. Compared with heavy-duty diesel vehicles, there is much larger uncertainty in BC emission factors for light-duty passenger vehicles (LDPVs), in particular for gasoline LDPVs, which warrants further studies. In this study, we employed the dynamometer and the Aethalometer (AE-51) to measure second-by-second BC emissions from eight LDPVs by engine technology and driving cycle. The average BC emission factors under transient cycles (e.g., ECE-15, New European Driving Cycle, NEDC, Worldwide Harmonized Light Vehicles Test Cycle, WLTC) are 3.6-91.5 mg/km, 7.6 mg/km and 0.13-0.58 mg/km, respectively, for diesel (N = 3), gasoline direct injection (GDI) (N = 1) and gasoline port-fuel injection (PFI) engine categories (N = 4). For gasoline PFI LDPVs, the instantaneous emission profiles show a strong association of peak BC emissions with cold-start and high-speed aggressive driving. Such impacts lead to considerable BC emission contributions in cold-start periods (e.g., the first 47 s-94 s) over the entire cycle (e.g., 18-76% of the NEDC and 13-36% of the WLTC) and increased BC emission factors by 80-440% under the WLTC compared to the NEDC. For diesel BC emissions, the size distribution exhibits a typical unimodal pattern with one single peak appearing approximately from 120 to 150 nm, which is largely consistent with previous studies. Nevertheless, the average mass ratios of BC to particle mass (PM) range from 0.38 to 0.54 for three diesel samples, representing substantial impacts from both driving and engine conditions. The significant discrepancy between gasoline BC emission factors obtained from tailpipe exhaust versus ambient conditions suggest that more comparative

Simultaneous high crystallinity and sub-bandgap optical absorptance in hyperdoped black silicon using nanosecond laser annealing

Energy Technology Data Exchange (ETDEWEB)

Franta, Benjamin, E-mail: bafranta@gmail.com; Pastor, David; Gandhi, Hemi H.; Aziz, Michael J.; Mazur, Eric [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States); Rekemeyer, Paul H.; Gradečak, Silvija [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2015-12-14

Hyperdoped black silicon fabricated with femtosecond laser irradiation has attracted interest for applications in infrared photodetectors and intermediate band photovoltaics due to its sub-bandgap optical absorptance and light-trapping surface. However, hyperdoped black silicon typically has an amorphous and polyphasic polycrystalline surface that can interfere with carrier transport, electrical rectification, and intermediate band formation. Past studies have used thermal annealing to obtain high crystallinity in hyperdoped black silicon, but thermal annealing causes a deactivation of the sub-bandgap optical absorptance. In this study, nanosecond laser annealing is used to obtain high crystallinity and remove pressure-induced phases in hyperdoped black silicon while maintaining high sub-bandgap optical absorptance and a light-trapping surface morphology. Furthermore, it is shown that nanosecond laser annealing reactivates the sub-bandgap optical absorptance of hyperdoped black silicon after deactivation by thermal annealing. Thermal annealing and nanosecond laser annealing can be combined in sequence to fabricate hyperdoped black silicon that simultaneously shows high crystallinity, high above-bandgap and sub-bandgap absorptance, and a rectifying electrical homojunction. Such nanosecond laser annealing could potentially be applied to non-equilibrium material systems beyond hyperdoped black silicon.

Light at deep sea hydrothermal vents

Science.gov (United States)

Van Dover, Cindy Lee; Cann, J. R.; Cavanaugh, Colleen; Chamberlain, Steven; Delaney, John R.; Janecky, David; Imhoff, Johannes; Tyson, J. Anthony

We usually think of the bottom of the sea as a dark environment, lit only by flashes of bioluminescent light. Discovery of light associated with geothermal processes at deep sea hydrothermal vents forces us to qualify our textbook descriptions of the seafloor as a uniformly dark environment. While a very dim glow emitted from high temperature (350°) vents (black smokers) at mid-oceanic ridge spreading centers has been documented [Van Dover et al, 1988], the source of this light and its role, if any, in the evolution and adaptation of photobiochemical processes have yet to be determined. Preliminary studies indicate that thermal radiation alone may account for the “glow” ]Smith and Delaney, 1989] and that a novel photoreceptor in shrimp-colonizing black smoker chimneys may detect this “glow” [Van Dover et al., 1989; Pelli and Chamberlain, 1989]. A more controversial question, posed by C. L. Van Dover, J. R. Cann, and J. R. Delaney at the 1993 LITE Workshop at the Woods Hole Oceanographic Institution in Massachusetts, is whether there may be sufficient light of appropriate wavelengths to support geothermally driven photosynthesis by microorganisms.

Superresolving Black Hole Images with Full-Closure Sparse Modeling

Science.gov (United States)

Crowley, Chelsea; Akiyama, Kazunori; Fish, Vincent

2018-01-01

It is believed that almost all galaxies have black holes at their centers. Imaging a black hole is a primary objective to answer scientific questions relating to relativistic accretion and jet formation. The Event Horizon Telescope (EHT) is set to capture images of two nearby black holes, Sagittarius A* at the center of the Milky Way galaxy roughly 26,000 light years away and the other M87 which is in Virgo A, a large elliptical galaxy that is 50 million light years away. Sparse imaging techniques have shown great promise for reconstructing high-fidelity superresolved images of black holes from simulated data. Previous work has included the effects of atmospheric phase errors and thermal noise, but not systematic amplitude errors that arise due to miscalibration. We explore a full-closure imaging technique with sparse modeling that uses closure amplitudes and closure phases to improve the imaging process. This new technique can successfully handle data with systematic amplitude errors. Applying our technique to synthetic EHT data of M87, we find that full-closure sparse modeling can reconstruct images better than traditional methods and recover key structural information on the source, such as the shape and size of the predicted photon ring. These results suggest that our new approach will provide superior imaging performance for data from the EHT and other interferometric arrays.

Brown dwarfs and black holes

International Nuclear Information System (INIS)

Tarter, J.C.

1978-01-01

The astronomical missing-mass problem (the discrepancy between the dynamical mass estimate and the sum of individual masses in large groupings) is considered, and possible explanations are advanced. The existence of brown dwarfs (stars not massive enough to shine by nuclear burning) and black holes (extremely high density matter contraction such that gravitation allows no light emission) thus far provides the most plausible solutions

Transformational Leadership VS : Transactional Leadership. The Influence of Gender and Culture on Leadership Styles of SMEs in China and Sweden

OpenAIRE

Xiaoxia, Pan; Xiaoxia, Pan; Jing, Wu

2006-01-01

Transformational and transactional leadership, which focus on the relationship between leaders and employees, are the most recent development of leadership theories. Yet studies on the impact of gender and culture on transformational and transactional leadership styles are limited. This Master Dissertation therefore aims to shed new light on that issue. First, it attempts to compare leadership styles adopted by managers of SMEs in China and Sweden. Second, it tries to evaluate which element -...

Style drift in private equity

NARCIS (Netherlands)

Cumming, D.; Fleming, G.; Schwienbacher, A.

2009-01-01

We introduce the concept of style drift to private equity investment. We present theory and evidence pertaining to style drifts in terms of a fund manager's stated focus on particular stages of entrepreneurial development. We develop a model that derives conditions under which style drifts are less

Black carbon and mineral dust in snow cover on the Tibetan Plateau

Science.gov (United States)

Zhang, Yulan; Kang, Shichang; Sprenger, Michael; Cong, Zhiyuan; Gao, Tanguang; Li, Chaoliu; Tao, Shu; Li, Xiaofei; Zhong, Xinyue; Xu, Min; Meng, Wenjun; Neupane, Bigyan; Qin, Xiang; Sillanpää, Mika

2018-02-01

Snow cover plays a key role for sustaining ecology and society in mountainous regions. Light-absorbing particulates (including black carbon, organic carbon, and mineral dust) deposited on snow can reduce surface albedo and contribute to the near-worldwide melting of snow and ice. This study focused on understanding the role of black carbon and other water-insoluble light-absorbing particulates in the snow cover of the Tibetan Plateau (TP). The results found that the black carbon, organic carbon, and dust concentrations in snow cover generally ranged from 202 to 17 468 ng g-1, 491 to 13 880 ng g-1, and 22 to 846 µg g-1, respectively, with higher concentrations in the central to northern areas of the TP. Back trajectory analysis suggested that the northern TP was influenced mainly by air masses from Central Asia with some Eurasian influence, and air masses in the central and Himalayan region originated mainly from Central and South Asia. The relative biomass-burning-sourced black carbon contributions decreased from ˜ 50 % in the southern TP to ˜ 30 % in the northern TP. The relative contribution of black carbon and dust to snow albedo reduction reached approximately 37 and 15 %, respectively. The effect of black carbon and dust reduced the snow cover duration by 3.1 ± 0.1 to 4.4 ± 0.2 days. Meanwhile, the black carbon and dust had important implications for snowmelt water loss over the TP. The findings indicate that the impacts of black carbon and mineral dust need to be properly accounted for in future regional climate projections, particularly in the high-altitude cryosphere.

Personality, Humor Styles and Happiness: Happy People Have Positive Humor Styles

Science.gov (United States)

Ford, Thomas E.; Lappi, Shaun K.; Holden, Christopher J.

2016-01-01

The present study examined the relationships between four personality traits, humor styles, and happiness. Replicating previous research, happiness was positively correlated with four personality traits: extraversion, locus of control, self-esteem, and optimism. Further, happiness positively related to self-enhancing and affiliative humor styles; it related negatively to self-defeating and aggressive humor styles. Thus, happy people habitually engage in positive uses of humor and avoid engaging in negative uses of humor in daily life. We also found support for our hypothesis. People high in extraversion, locus of control, self-esteem, and optimism are happier because they engage in positive humor in daily life. PMID:27547251

Personality, Humor Styles and Happiness: Happy People Have Positive Humor Styles

Directory of Open Access Journals (Sweden)

Thomas E. Ford

2016-08-01

Full Text Available The present study examined the relationships between four personality traits, humor styles, and happiness. Replicating previous research, happiness was positively correlated with four personality traits: extraversion, locus of control, self-esteem, and optimism. Further, happiness positively related to self-enhancing and affiliative humor styles; it related negatively to self-defeating and aggressive humor styles. Thus, happy people habitually engage in positive uses of humor and avoid engaging in negative uses of humor in daily life. We also found support for our hypothesis. People high in extraversion, locus of control, self-esteem, and optimism are happier because they engage in positive humor in daily life.

Personality, Humor Styles and Happiness: Happy People Have Positive Humor Styles.

Science.gov (United States)

Ford, Thomas E; Lappi, Shaun K; Holden, Christopher J

2016-08-01

The present study examined the relationships between four personality traits, humor styles, and happiness. Replicating previous research, happiness was positively correlated with four personality traits: extraversion, locus of control, self-esteem, and optimism. Further, happiness positively related to self-enhancing and affiliative humor styles; it related negatively to self-defeating and aggressive humor styles. Thus, happy people habitually engage in positive uses of humor and avoid engaging in negative uses of humor in daily life. We also found support for our hypothesis. People high in extraversion, locus of control, self-esteem, and optimism are happier because they engage in positive humor in daily life.

Black hole chromosphere at the CERN LHC

International Nuclear Information System (INIS)

Anchordoqui, Luis; Goldberg, Haim

2003-01-01

If the scale of quantum gravity is near a TeV, black holes will be copiously produced at the CERN LHC. In this work we study the main properties of the light descendants of these black holes. We show that the emitted partons are closely spaced outside the horizon, and hence they do not fragment into hadrons in vacuum but more likely into a kind of quark-gluon plasma. Consequently, the thermal emission occurs far from the horizon, at a temperature characteristic of the QCD scale. We analyze the energy spectrum of the particles emerging from the 'chromosphere', and find that the hard hadronic jets are almost entirely suppressed. They are replaced by an isotropic distribution of soft photons and hadrons, with hundreds of particles in the GeV range. This provides a new distinctive signature for black hole events at LHC

Styles of Success: Research on Gender Differences in Management Styles [and] What Is the Most Important Difference in Management Styles between Men and Women?

Science.gov (United States)

Small Business Forum, 1995

1995-01-01

Responses to the Success Style Profile from 127 men and women businessowners and reactions from an 8-member panel found that male and female entrepreneurs resemble each other more than they resemble nonentrepreneurs in thinking and management styles. Women favor right-brain, intuitive styles. One conclusion is that both ways have strengths. (JOW)

The Relationship of Decision-Making Styles and Attributional Styles in Addicted and Non-addicted Men.

Science.gov (United States)

Shaghaghy, Farhad; Saffarinia, Majid; Iranpoor, Mohadeseh; Soltanynejad, Ali

2011-01-01

One of social problems which has affected our society and resulted in problems for different groups of people is drug abuse. This issue indicates a serious psychological, physical and social problem in community. Social skills have positive and successful influences in prevention of substance abuse. This includes the ability to explain events correctly and then appropriate decision making. This study compares decision making styles and attributional styles between addicted and non addicted men to recognize their role in addiction. In this study, 200 addicted and non addicted men were randomly selected. Decision-making style and attributional style questionnaires were used. Data analysis was performed by independent Student's t and Pearson correlation tests. The study population included 81 addicted and 90 non-addicted men. Addicted and non addicted men were significantly different in rational decision-making style (P rational decision making and optimistic attribution style (r = -0.305, P rational decision making and learned helplessness (r = 0.309, P rational in decision making and addicts that developed learned helplessness were less rational and did not have optimistic attribution style. These issues show that addiction institutions and therapists have to pay attention to cognitive factors for addiction prevention.

Looking for the invisible universe - Black matter, black energy, black holes

International Nuclear Information System (INIS)

Elbaz, David

2016-01-01

As the discovery of the expansion of the universe and of black holes put the study of cosmology into question again because it now refers to invisible things such as black holes, black energy and black matter, the author proposes an other view on the universe within such a context. He first discusses these three enigmas of black matter, black energy and black holes. In a second part, he addresses, discusses and comments five illusions: the Uranian illusion (questions of the existence of an anti-world, of black matter temperature), the Mercurian illusion (quantum gravity, the string theory), the Martian illusion (a patchwork universe, the illusion of the infinite), the cosmic Maya (the John Wheeler's cup, the holographic universe), and the narcissistic illusion

Active galactic nucleus black hole mass estimates in the era of time domain astronomy

Energy Technology Data Exchange (ETDEWEB)

Kelly, Brandon C.; Treu, Tommaso; Pancoast, Anna [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106-9530 (United States); Malkan, Matthew [Department of Astronomy, 430 Portola Plaza, Box 951547, University of California, Los Angeles, CA 90095-1547 (United States); Woo, Jong-Hak [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)

2013-12-20

We investigate the dependence of the normalization of the high-frequency part of the X-ray and optical power spectral densities (PSDs) on black hole mass for a sample of 39 active galactic nuclei (AGNs) with black hole masses estimated from reverberation mapping or dynamical modeling. We obtained new Swift observations of PG 1426+015, which has the largest estimated black hole mass of the AGNs in our sample. We develop a novel statistical method to estimate the PSD from a light curve of photon counts with arbitrary sampling, eliminating the need to bin a light curve to achieve Gaussian statistics, and we use this technique to estimate the X-ray variability parameters for the faint AGNs in our sample. We find that the normalization of the high-frequency X-ray PSD is inversely proportional to black hole mass. We discuss how to use this scaling relationship to obtain black hole mass estimates from the short timescale X-ray variability amplitude with precision ∼0.38 dex. The amplitude of optical variability on timescales of days is also anticorrelated with black hole mass, but with larger scatter. Instead, the optical variability amplitude exhibits the strongest anticorrelation with luminosity. We conclude with a discussion of the implications of our results for estimating black hole mass from the amplitude of AGN variability.

Style popularity and the comovement of stocks

NARCIS (Netherlands)

Wouters, T.; Plantinga, A.

2006-01-01

We examine to what extent the popularity of an investment style can be attributed to style investing. The style investing hypothesis predicts that assets in the same style show strong comovement with respect to their underlying fundamentals and that reclassifying assets into a new style raises its

Parenting Style Transitions and Delinquency

Science.gov (United States)

Schroeder, Ryan D.; Mowen, Thomas J.

2014-01-01

Parenting style has been extensively analyzed as a contributor to juvenile delinquency in the criminological literature, but no research to date has assessed the prevalence of parenting style changes during adolescence or the influence of such parenting style changes on juvenile delinquency. Drawing from the life course theory, the results show…

The impact of perceived parenting styles on attachment styles, self-evaluations and close relationships

OpenAIRE

Sümer, N; Güngör, Derya

1999-01-01

The present study examined the interplay between the perceived parenting styles of the university students and attachment styles, basic self-dimensions, behavior patterns in close relationships, and relationship satisfaction. The findings indicated that parenting styles (authoritarian, authoritative, permissive/indulgent, and permissive/neglecting), which were constructed by crossing perceived parental acceptance/involment and strict control dimensions of parenting were consistently related w...

THE DISCOVERY OF PERIODIC MODULATIONS IN THE OPTICAL SPECTRA OF GALAXIES, POSSIBLY DUE TO ULTRARAPID LIGHT BURSTS FROM THEIR MASSIVE CENTRAL BLACK HOLES

Energy Technology Data Exchange (ETDEWEB)

Borra, Ermanno F., E-mail: borra@phy.ulaval.ca [Centre d' Optique, Photonique et Laser, Departement de Physique, Universite Laval, Quebec, G1K 7P4 Quebec (Canada)

2013-09-10

A Fourier transform analysis of 2.5 million spectra in the SDSS survey was carried out to detect periodic modulations contained in the intensity versus frequency spectrum. A statistically significant signal was found for 223 galaxies, while the spectra of 0.9 million galaxies were observed. A plot of the periods as a function of redshift clearly shows that the effect is real without any doubt, because the modulations are quantized at two base periods that increase with redshift in two very tight parallel linear relations. We suggest that this result could be caused by light bursts separated by times on the order of 10{sup -13} s, but other causes may be possible. We investigate the hypothesis that the modulation is generated by the Fourier transform of spectral lines, but conclude that this hypothesis is not valid. Although the light burst suggestion implies absurdly high temperatures, it is supported by the fact that the Crab pulsar also has extremely short unresolved pulses (<0.5 ns) that imply similarly high temperatures. Furthermore, the radio spectrum of the Crab pulsar also has spectral bands similar to those that have been detected. Finally, decreasing the signal-to-noise threshold of detection gives results consistent with beamed signals having a small beam divergence, as expected from non-thermal sources that send a jet, like those seen in pulsars. Considering that galaxy centers contain massive black holes, exotic black hole physics may be responsible for the spectral modulation. However, at this stage, this idea is only a hypothesis to be confirmed with further work.

Dry Etch Black Silicon with Low Surface Damage: Effect of Low Capacitively Coupled Plasma Power

DEFF Research Database (Denmark)

Iandolo, Beniamino; Plakhotnyuk, Maksym; Gaudig, Maria

2017-01-01

Black silicon fabricated by reactive ion etch (RIE) is promising for integration into silicon solar cells thanks to its excellent light trapping ability. However, intensive ion bombardment during the RIE induces surface damage, which results in enhanced surface recombination velocity. Here, we pr...... carrier lifetime thanks to reduced ion energy. Surface passivation using atomic layer deposition of Al2O3 improves the effective lifetime to 7.5 ms and 0.8 ms for black silicon n- and p-type wafers, respectively.......Black silicon fabricated by reactive ion etch (RIE) is promising for integration into silicon solar cells thanks to its excellent light trapping ability. However, intensive ion bombardment during the RIE induces surface damage, which results in enhanced surface recombination velocity. Here, we...... present a RIE optimization leading to reduced surface damage while retaining excellent light trapping and low reflectivity. In particular, we demonstrate that the reduction of the capacitively coupled power during reactive ion etching preserves a reflectance below 1% and improves the effective minority...

The German Version of the Humor Styles Questionnaire: Psychometric Properties and Overlap With Other Styles of Humor.

Science.gov (United States)

Ruch, Willibald; Heintz, Sonja

2016-08-01

The Humor Styles Questionnaire (HSQ; Martin et al., 2003) is one of the most frequently used questionnaires in humor research and has been adapted to several languages. The HSQ measures four humor styles (affiliative, self-enhancing, aggressive, and self-defeating), which should be adaptive or potentially maladaptive to psychosocial well-being. The present study analyzes the internal consistency, factorial validity, and factorial invariance of the HSQ on the basis of several German-speaking samples combined (total N = 1,101). Separate analyses were conducted for gender (male/female), age groups (16-24, 25-35, >36 years old), and countries (Germany/Switzerland). Internal consistencies were good for the overall sample and the demographic subgroups (.80-.89), with lower values obtained for the aggressive scale (.66-.73). Principal components and confirmatory factor analyses mostly supported the four-factor structure of the HSQ. Weak factorial invariance was found across gender and age groups, while strong factorial invariance was supported across countries. Two subsamples also provided self-ratings on ten styles of humorous conduct (n = 344) and of eight comic styles (n = 285). The four HSQ scales showed small to large correlations to the styles of humorous conduct (-.54 to .65) and small to medium correlations to the comic styles (-.27 to .42). The HSQ shared on average 27.5-35.0% of the variance with the styles of humorous conduct and 13.0-15.0% of the variance with the comic styles. Thus-despite similar labels-these styles of humorous conduct and comic styles differed from the HSQ humor styles.

Synthesis and luminescence of nanodiamonds from carbon black

International Nuclear Information System (INIS)

Hu Shengliang; Tian Fei; Bai Peikang; Cao Shirui; Sun Jing; Yang Jing

2009-01-01

Dispersed nanodiamonds just several nanometers in diameter have been successfully synthesized using carbon black as the carbon source by a long-pulse-width laser irradiation in water at room temperature and normal pressure. The produced nanodiamonds can emit strong visible light after simple surface passivation. The light emission is attributed to the surface states related to linkage groups formed on nanodiamond surface. The surface-passivated nanodiamonds with stable photoluminescence have high potential application in bioimaging and medicine

JPRS Report, Soviet Union, International Affairs.

Science.gov (United States)

1987-06-25

and in the almost still oily-black water we could see the twinkling lights from the skyscraper hotels built after the proclamation of "infitah...Heliopolis can boast green squares and brilliant store windows and boutiques Paris style. But Heliopolis is not all Cairo. Not far from the citadel raised

Education in the Black Diaspora: Perspectives, Challenges, and Prospects. Routledge Research in Education

Science.gov (United States)

Freeman, Kassie, Ed.; Johnson, Ethan, Ed.

2011-01-01

This volume gathers scholars from around the world in a comparative approach to the various educational struggles of people of African descent, advancing the search for solutions and bringing to light new facets of the experiences of black people in the era of globalization. This book begins with "Black Populations in the Diaspora:…

Humor and creative life styles.

Science.gov (United States)

Richman, J

2001-01-01

This paper is based upon the writings of William James in the late 19th century, and Alfred Adler and Sigmund Freud in the 20th, enriched by the contributions of later personality and role theorists. The self is defined as the unique organization of each person; a style is the self in action. Different life styles and their components are expressed in different situations. I posit that humor and positive thinking, combined with meaning and purpose, are vital components of all constructive life styles. The knowledge of life styles cuts through diagnostic labels to reveal our universal humanity. It can be fruitfully applied to patients and nonpatients alike and, I found, for the self-understanding of therapist. The clinical application of life styles is illustrated through numerous vignettes.

Intercultural conflict styles: literature review

Directory of Open Access Journals (Sweden)

Batkhina A.A.

2017-10-01

Full Text Available Analytical review of foreign psychological research on the international conflict styles is presented in this article. Intercultural conflict is understood as an interpersonal conflict between representatives of different cultures. The main models describing the intercultural conflict styles are analyzed: the dual concern model, the intercultural conflict styles inventory model, the face negotiation model. The publication provides a brief review of modern studies’ results of behavior predictors in the intercultural conflict; special attention is paid to the analysis of the influence of culture and intercultural communication apprehension on the choice of conflict styles. The importance of assessing the conflict styles effectiveness used in the situation of intercultural interaction is noted. In conclusion, unresolved problems and actual trends in the study of behavior in the intercultural conflict are designated.

Impacts of Different Culture on Management Style

Institute of Scientific and Technical Information of China (English)

陈国君

2015-01-01

cultural differences affect the management behavior and management style.Participatory management style in the United States and instructional management style in China has a deep cultural roots.In terms of the type of management style,they are equal.As long as management style is consistent with its culture accordingly,the leadership will be effective.

The Crisis in Black and Black.

Science.gov (United States)

Hutchinson, Earl Ofari

These essays explore why the historic conflict between blacks and whites in the United States has become a crisis that divides many African Americans. The changing racial dynamic is not marked by conflicts. between the black middle class and the poor, black men and women, the black intellectual elite and rappers, black politicians and the urban…

Retrograde versus Prograde Models of Accreting Black Holes

Directory of Open Access Journals (Sweden)

David Garofalo

2013-01-01

Full Text Available There is a general consensus that magnetic fields, accretion disks, and rotating black holes are instrumental in the generation of the most powerful sources of energy in the known universe. Nonetheless, because magnetized accretion onto rotating black holes involves both the complications of nonlinear magnetohydrodynamics that currently cannot fully be treated numerically, and uncertainties about the origin of magnetic fields that at present are part of the input, the space of possible solutions remains less constrained. Consequently, the literature still bears witness to the proliferation of rather different black hole engine models. But the accumulated wealth of observational data is now sufficient to meaningfully distinguish between them. It is in this light that this critical paper compares the recent retrograde framework with standard “spin paradigm” prograde models.

Nature of Microscopic Black Holes and Gravity in Theories with Particle Species

CERN Document Server

Dvali, Gia

2010-01-01

Relying solely on unitarity and the consistency with large-distance black hole physics, we derive model-independent properties of the microscopic black holes and of short-distance gravity in theories with N particle species. In this class of theories black holes can be as light as M_{Planck}/\\sqrt{N} and be produced in particle collisions above this energy. We show, that the micro black holes must come in the same variety as the species do, although their label is not associated with any conserved charge measurable at large distances. In contrast with big Schwarzschildian ones, the evaporation of the smallest black holes is maximally undemocratic and is biased in favor of particular species. With an increasing mass the democracy characteristic to the usual macro black holes is gradually regained. The lowest possible mass above which black holes become Einsteinian is \\sqrt{N} M_{Planck}. This fact uncovers the new fundamental scale (below the quantum gravity scale) above which gravity changes classically, and ...

Collisions Around a Black Hole Mean Mealtime

Science.gov (United States)

Kohler, Susanna

2017-08-01

When a normally dormant supermassive black hole burps out a brief flare, its assumed that a star was torn apart and fell into the black hole. But a new study suggests that some of these flares might have a slightly different cause.Not a Disruption?Artists impression of a tidal disruption event, in which a star has been pulled apart and its gas feeds the supermassive black hole. [NASA/JPL-Caltech]When a star swings a little too close by a supermassive black hole, the black holes gravity can pull the star apart, completely disrupting it. The resulting gas can then accrete onto the black hole, feeding it and causing it to flare. The predicted frequency of these tidal disruption events and their expected light curves dont perfectly match all our observations of flaring black holes, however.This discrepancy has led two scientists from the Columbia Astrophysics Laboratory, Brian Metzger and Nicholas Stone, to wonder if we can explain flares from supermassive black holes in another way. Could a differentevent masquerade as a tidal disruption?Evolution of a stars semimajor axis (top panel) and radius (bottom panel) as a function of time since Roche-lobe overflow began onto a million-solar-mass black hole. Curves show stars of different masses. [Metzger Stone 2017]Inspirals and OutspiralsIn the dense nuclear star cluster surrounding a supermassive black hole, various interactions can send stars on new paths that take them close to the black hole. In many of these interactions, the stars will end up on plunging orbits, often resulting in tidal disruption. But sometimes stars can approach the black hole on tightly bound orbits with lower eccentricities.A main-sequence star on such a path, in what is known as an extreme mass ratio inspiral (EMRI), slowly approaches the black hole over a period of millions of years, eventually overflowing its Roche lobe and losing mass. Theradius of the star inflates, driving more mass loss and halting the stars inward progress. The star then

Investigating aggressive styles and defense mechanisms in bipolar patients and in their parents

Directory of Open Access Journals (Sweden)

Nicola Luigi Bragazzi

2014-10-01

Full Text Available Bipolar disorder (BD is a very common mental health disorder, whose etiology concerning aggressive styles and defense mechanisms is still poorly known despite the efforts dedicated to develop psychological and biological theories. After obtaining written signed informed consent, this study will recruit inpatients with a clinical diagnosis of BD, based on Structured Clinical Interview and the Diagnostic and Statistical Manual of Mental Disorders criteria, and their parents. The Bus-Perry Aggression Questionnaire, the Defense Style Questionnaire 40, the Symptom check list SCL-90-R, developed by DeRogatis will be administered to the participants, together with a semi-structured questionnaire concerning demographic data (age, gender, employment, education and only for the patients clinical information (onset year of the disorder, presence of co-morbidities, alcohol and drug use, suicide tendencies, kind of treatment. All the questionnaires are in the Italian validated version. The successful completion of this study will shed light on the relationship between aggressive styles and defensive mechanisms in bipolar inpatients and in their parents, helping the clinicians to develop ad hoc psychological interventions.

Style popularity and the comovement of stocks

OpenAIRE

Wouters, T.; Plantinga, A.

2006-01-01

We examine to what extent the popularity of an investment style can be attributed to style investing. The style investing hypothesis predicts that assets in the same style show strong comovement with respect to their underlying fundamentals and that reclassifying assets into a new style raises its correlation with that style. We test this prediction by studying how comovement varies with proxies of popularity. We use different kinds of data, such as data on stocks, mutual funds, IPO?s and fin...

HUBBLE provides multiple views of how to feed a black hole

Science.gov (United States)

1998-05-01

Although the cause-and-effect relationships are not yet clear, the views provided by complementary images from two instruments aboard the Hubble Space Telescope are giving astronomers new insights into the powerful forces being exerted in this complex maelstrom. Researchers believe these forces may even have shifted the axis of the massive black hole from its expected orientation. The Hubble wide-field camera visible image of the merged Centaurus A galaxy, also called NGC 5128, shows in sharp clarity a dramatic dark lane of dust girdling the galaxy. Blue clusters of newborn stars are clearly resolved, and silhouettes of dust filaments are interspersed with blazing orange-glowing gas. Located only 10 million light-years away, this peculiar-looking galaxy contains the closest active galactic nucleus to Earth and has long been considered an example of an elliptical galaxy disrupted by a recent collision with a smaller companion spiral galaxy. Using the infrared vision of Hubble, astronomers have penetrated this wall of dust for the first time to see a twisted disk of hot gas swept up in the black hole's gravitational whirlpool. The suspected black hole is so dense it contains the mass of perhaps a billion stars, compacted into a small region of space not much larger than our Solar System. Resolving features as small as seven light-years across, Hubble has shown astronomers that the hot gas disk is tilted in a different direction from the black hole's axis -- like a wobbly wheel around an axle. The black hole's axis is identified by the orientation of a high-speed jet of material, glowing in X-rays and radio frequencies, blasted from the black hole at 1/100th the speed of light. This gas disk presumably fueling the black hole may have formed so recently it is not yet aligned to the black hole's spin axis, or it may simply be influenced more by the galaxy's gravitational tug than by the black hole's. "This black hole is doing its own thing. Aside from receiving fresh

Destruction and recreation of black holes

Science.gov (United States)

Bell, Peter M.

Even though the existence of the gravitationally collapsed concentrations of matter in space known as ‘black holes’ is accepted at all educational levels in our society, the basis for the black hole concept is really only the result of approximate calculations done over 40 years ago. The concept of the black hole is an esoteric subject, and recently the mathematical and physical frailties of the concept have come to light in an interesting round of theoretical shuffling. The recent activity in theorizing about black holes began about 10 years ago, when Cambridge University mathematican Stephen Hawking calculated that black holes could become unstable by losing mass and thus ‘evaporate.’ Hawking's results were surprisingly well received, considering the lack of theoretical understanding of the relations between quantum mechanics and relativity. (There is no quantized theory of gravitation, even today.) Nonetheless, his semiclassical calculations implied that the rate of ‘evaporation’ of a black hole would be slower than the rate of degradation of the universe. In fact, based on these and other calculations, the British regard Hawking as ‘the nearest thing we have to a new Einstein’ [New Scientist, Oct. 9, 1980]. Within the last few months, Frank Tipler, provocative mathematical physicist at the University of Texas, has reexamined Hawking's calculations [Physical Review Letters, 45, 941, 1980], concluding, in simple terms, (1) that because of possible vital difficulties in the assumptions, the very concept of black holes could be wrong; (2) that Hawkings' evaporation hypothesis is so efficient that a black hole once created must disappear in less than a second; or (3) that he, Tipler, may be wrong. The latter possibility has been the conclusion of physicist James Bardeen of the University of Washington, who calculated that black hole masses do evaporate but they do so according to Hawking's predicted rate and that Tipler's findings cause only a second

Development of an Instrument to Measure Teaching Style in Japan: The Teaching Style Assessment Scale

Science.gov (United States)

Yoshida, Fumiko; Conti, Gary J.; Yamauchi, Toyoaki; Iwasaki, Takaaki

2014-01-01

Teaching style has been a popular concept for many years. Teaching style refers to the distinct qualities displayed by a teacher that are persistent from situation to situation regardless of the content. The Principles of Adult Learning Scale (PALS) has been used extensively in the West for measuring teaching style in relationship to the adult…

The role of parenting styles and teacher interactional styles in children's reading and spelling development.

Science.gov (United States)

Kiuru, Noona; Aunola, Kaisa; Torppa, Minna; Lerkkanen, Marja-Kristiina; Poikkeus, Anna-Maija; Niemi, Pekka; Viljaranta, Jaana; Lyyra, Anna-Liisa; Leskinen, Esko; Tolvanen, Asko; Nurmi, Jari-Erik

2012-12-01

This study examined the associations between parenting styles, teacher interactional styles, and children's reading and spelling skills. The sample consisted of 864 Finnish-speaking children and their parents (864 mothers, 864 fathers) and teachers (N=123). Children's risk for reading disabilities and reader status were assessed in kindergarten. Children were also tested on reading and spelling skills in Grades 1 and 2. Parenting styles and teacher interactional styles were measured using parents' and teachers' self-reports in Grade 1. First, the results indicated that both an authoritative parenting style and authoritative teacher interactional style positively predicted children's spelling skill development. Second, authoritative parenting was particularly beneficial for the spelling skill development of children who were at risk for reading disabilities. Third, authoritative teaching promoted spelling skill development particularly among children who were nonreaders in kindergarten but had no risk for reading disabilities. Finally, some evidence was found that authoritative teaching could compensate for the negative impact of nonauthoritative parenting on reading development among kindergarten nonreaders. Copyright © 2012 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Different Styles for Different Needs – The Effect of Cognitive Styles on Idea Generation

OpenAIRE

Lomberg, Carina; Kollmann, Tobias; Stockmann, Christoph

2017-01-01

Researchers are engaged in finding the precursors for innovation. Drawing on Kirton's Adaption-Innovation (KAI) Inventory, we explicitly test Kirton's central premise that cognitive styles differentiate between preferences for producing ideas in a certain way. We argue that the generation of either a magnitude or original ideas is governed by different underlying cognitive styles. In a study with 191 individuals, we find that the cognitive style originality associates with ideational fluency ...

Development and Validation of a Q-Sort Measure of Identity Processing Style: The Identity Processing Style Q-Sort

Science.gov (United States)

Pittman, Joe F.; Kerpelman, Jennifer L.; Lamke, Leanne K.; Sollie, Donna L.

2009-01-01

Identity styles represent strategies individuals use to explore identity-related issues. Berzonsky (Berzonsky, M. D. (1992). Identity style and coping strategies. "Journal of Personality, 60", 771-788) identified three styles: informational, normative, and diffuse. In three studies, this paper presents (a) the identity processing style Q-sort…

Contemporary genetic structure and postglacial demographic history of the black scorpionfish, Scorpaena porcus, in the Mediterranean and the Black Seas.

Science.gov (United States)

Boissin, E; Micu, D; Janczyszyn-Le Goff, M; Neglia, V; Bat, L; Todorova, V; Panayotova, M; Kruschel, C; Macic, V; Milchakova, N; Keskin, Ç; Anastasopoulou, A; Nasto, I; Zane, L; Planes, S

2016-05-01

Understanding the distribution of genetic diversity in the light of past demographic events linked with climatic shifts will help to forecast evolutionary trajectories of ecosystems within the current context of climate change. In this study, mitochondrial sequences and microsatellite loci were analysed using traditional population genetic approaches together with Bayesian dating and the more recent approximate Bayesian computation scenario testing. The genetic structure and demographic history of a commercial fish, the black scorpionfish, Scorpaena porcus, was investigated throughout the Mediterranean and Black Seas. The results suggest that the species recently underwent population expansions, in both seas, likely concomitant with the warming period following the Last Glacial Maximum, 20 000 years ago. A weak contemporaneous genetic differentiation was identified between the Black Sea and the Mediterranean Sea. However, the genetic diversity was similar for populations of the two seas, suggesting a high number of colonizers entered the Black Sea during the interglacial period and/or the presence of a refugial population in the Black Sea during the glacial period. Finally, within seas, an east/west genetic differentiation in the Adriatic seems to prevail, whereas the Black Sea does not show any structured spatial genetic pattern of its population. Overall, these results suggest that the Black Sea is not that isolated from the Mediterranean, and both seas revealed similar evolutionary patterns related to climate change and changes in sea level. © 2016 John Wiley & Sons Ltd.

Black-Scholes finite difference modeling in forecasting of call warrant prices in Bursa Malaysia

Science.gov (United States)

Mansor, Nur Jariah; Jaffar, Maheran Mohd

2014-07-01

Call warrant is a type of structured warrant in Bursa Malaysia. It gives the holder the right to buy the underlying share at a specified price within a limited period of time. The issuer of the structured warrants usually uses European style to exercise the call warrant on the maturity date. Warrant is very similar to an option. Usually, practitioners of the financial field use Black-Scholes model to value the option. The Black-Scholes equation is hard to solve analytically. Therefore the finite difference approach is applied to approximate the value of the call warrant prices. The central in time and central in space scheme is produced to approximate the value of the call warrant prices. It allows the warrant holder to forecast the value of the call warrant prices before the expiry date.

Nurse managers' leadership styles in Finland.

Science.gov (United States)

Vesterinen, Soili; Suhonen, Marjo; Isola, Arja; Paasivaara, Leena

2012-01-01

Nurse managers who can observe their own behaviour and its effects on employees can adjust to a better leadership style. The intention of this study was to explore nurses' and supervisors' perceptions of nurse managers' leadership styles. Open-ended interviews were conducted with 11 nurses and 10 superiors. The data were analysed by content analysis. In the study, six leadership styles were identified: visionary, coaching, affiliate, democratic, commanding, and isolating. Job satisfaction and commitment as well as operation and development work, cooperation, and organizational climate in the work unit were the factors, affected by leadership styles. The nurse managers should consider their leadership style from the point of view of employees, situation factors, and goals of the organization. Leadership styles where employees are seen in a participatory role have become more common.

Nurse Managers' Leadership Styles in Finland

Science.gov (United States)

Vesterinen, Soili; Suhonen, Marjo; Isola, Arja; Paasivaara, Leena

2012-01-01

Nurse managers who can observe their own behaviour and its effects on employees can adjust to a better leadership style. The intention of this study was to explore nurses' and supervisors' perceptions of nurse managers' leadership styles. Open-ended interviews were conducted with 11 nurses and 10 superiors. The data were analysed by content analysis. In the study, six leadership styles were identified: visionary, coaching, affiliate, democratic, commanding, and isolating. Job satisfaction and commitment as well as operation and development work, cooperation, and organizational climate in the work unit were the factors, affected by leadership styles. The nurse managers should consider their leadership style from the point of view of employees, situation factors, and goals of the organization. Leadership styles where employees are seen in a participatory role have become more common. PMID:23008767

Nurse Managers’ Leadership Styles in Finland

Directory of Open Access Journals (Sweden)

Soili Vesterinen

2012-01-01

Full Text Available Nurse managers who can observe their own behaviour and its effects on employees can adjust to a better leadership style. The intention of this study was to explore nurses’ and supervisors’ perceptions of nurse managers’ leadership styles. Open-ended interviews were conducted with 11 nurses and 10 superiors. The data were analysed by content analysis. In the study, six leadership styles were identified: visionary, coaching, affiliate, democratic, commanding, and isolating. Job satisfaction and commitment as well as operation and development work, cooperation, and organizational climate in the work unit were the factors, affected by leadership styles. The nurse managers should consider their leadership style from the point of view of employees, situation factors, and goals of the organization. Leadership styles where employees are seen in a participatory role have become more common.

Do emergency medicine residents and faculty have similar learning styles when assessed with the Kolb learning style assessment tool?

Science.gov (United States)

Fredette, Jenna; O'Brien, Corinne; Poole, Christy; Nomura, Jason

2015-04-01

Experiential learning theory and the Kolb Learning Style Inventory (Kolb LSI) have influenced educators worldwide for decades. Knowledge of learning styles can create efficient learning environments, increase information retention, and improve learner satisfaction. Learning styles have been examined in medicine previously, but not specifically with Emergency Medicine (EM) residents and attendings. Using the Kolb LSI, the learning styles of Emergency Medicine residents and attendings were assessed. The findings showed that the majority of EM residents and attendings shared the accommodating learning style. This result was different than prior studies that found the majority of medical professionals had a converging learning style and other studies that found attendings often have different learning styles than residents. The issue of learning styles among emergency medical residents and attendings is important because learning style knowledge may have an impact on how a residency program structures curriculum and how EM residents are successfully, efficiently, and creatively educated.

On the W-hair of string black holes and the singularity problem

CERN Document Server

Ellis, John R.; Nanopoulos, Dimitri V.

1992-01-01

We argue that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers (W-hair) which characterise black hole states and maintain quantum coherence, even during exotic processes like black hole evaporation/decay. We study ways of measuring the W-hair of spherically-symmetric four-dimensional objects with event horizons, treated as effectively two-dimensional string black holes. Measurements can be done either through the s-wave scattering of light particles off the string black-hole background, or through interference experiments of Aharonov-Bohm type. We also speculate on the role of the extended W-symmetries possessed by the topological field theories that describe the region of space-time around a singularity.

Black layers on historical architecture.

Science.gov (United States)

Toniolo, Lucia; Zerbi, Carlotta M; Bugini, Roberto

2009-03-01

The external surface of any building in urban polluted environment is unavoidably destined to be covered with layers that assume a grey to black colour and are generally called 'black crusts'. These, according to standard protocols and glossary, are deteriorated surface layers of stone material; they can have variable thickness, are hard and fragile and can detach spontaneously from the substrate, which, in general, is quite decayed. Plain visual examination may lead to consider 'black crusts' all similar, whilst only a careful diagnostic investigation can distinguish 'black crusts' and the consequences of their formation on stone substrates. In this paper, various black layers on marble are studied and compared and the morphological and compositional characteristics discussed according to the related mechanisms of formation. Differences between old (hundred years) and recent crusts (30 years) are investigated and pointed out. Samples of black crusts collected from the Milan Cathedral façade (Candoglia Marble) have been studied and compared with the careful and synergic employ of traditional techniques: optical (transmission and reflected VIS light) and electron microscopy, X-ray spectrometry and micro-Fourier transform infrared spectroscopy. Visual examination of loose fragments does not allow to point out outstanding differences amongst the various samples; black layers have similar main mineral components, gypsum and airborne particles, with different spatial distribution. The microscopic studies allowed to point out the porosity differences, the gypsum crystallisation habit, different amount of embedded particles, level and progress of marble decay. The observations lead to define three main types of black crusts: black crust deriving from marble sulphation, compact deposit and encrustation due to exogenic materials deposition. Black crusts show evidence of sulphation in progress, without a clear continuity solution between crust and marble; the lack of

NuSTAR Observations of the Black Hole GS 1354-645: Evidence of Rapid Black Hole Spin

Science.gov (United States)

El-Batal, A. M.; Miller, J. M.; Reynolds, M. T.; Boggs, S. E.; Christensen, F. E.; Craig, W. W.; Fuerst, F.; Hailey, C. J.; Harrison, F. A.; Stern, D. K.;

Convergent validity of two decision making style measures

Directory of Open Access Journals (Sweden)

Berisha, Gentrit

2018-04-01

Full Text Available Decision making research has witnessed a growing number of studies on individual differences and decision making styles, yet the lack of comprehensive frameworks and widely accepted measures has hindered research for a long time. There is an ongoing debate on whether individuals’ styles dynamically change across time and situations according to circumstances. Furthermore, it is an open question whether these styles are mutually exclusive. Decision style measures seek to determine one’s dominant style as well as less used styles. To our knowledge this is the first study of the convergent validity of two widely used decision making style measures: The Decision Style Inventory (DSI and the General Decision Making Style (GDMS. The direction and strength of correlation between directive, analytical, conceptual and behavioral styles as measured by DSI and rational, intuitive, dependent, avoidant and spontaneous styles as measured by GDMS have been tested. Results of the current study are compared with previous studies that have used one or both of the instruments. Correlations between styles are consistent with findings from other studies using one of the decision style measures, but the strength of correlations indicates that there is no convergent validity between DSI and GDMS.

Fabrication of black-gold coatings by glancing angle deposition with sputtering

Directory of Open Access Journals (Sweden)

Alan Vitrey

2017-02-01

Full Text Available The fabrication of black-gold coatings using sputtering is reported here. Glancing angle deposition with a rotating substrate is needed to obtain vertical nanostructures. Enhanced light absorption is obtained in the samples prepared in the ballistic regime with high tilt angles. Under these conditions the diameter distribution of the nanostructures is centered at about 60 nm and the standard deviation is large enough to obtain black-metal behavior in the visible range.

Topological Aspects of Entropy and Phase Transition of Kerr Black Holes

Institute of Scientific and Technical Information of China (English)

YANG Guo-Hong; YAN Ji-Jiang; TIAN Li-Jun; DUAN Yi-Shi

2005-01-01

In the light of topological current and the relationship between the entropy and the Euler characteristic, the topological aspects of entropy and phase transition of Kerr black holes are studied. From Gauss-Bonnet-Chern theorem,it is shown that the entropy of Kerr black holes is determined by the singularities of the Killing vector field of spacetime.By calculating the Hopf indices and Brouwer degrees of the Killing vector field at the singularities, the entropy S = A/4for nonextreme Kerr black holes and S = 0 for extreme ones are obtained, respectively. It is also discussed that, with the change of the ratio of mass to angular momentum for unit mass, the Euler characteristic and the entropy of Kerr black holes will change discontinuously when the singularities on Cauchy horizon merge with the singularities on event horizon, which will lead to the first-order phase transition of Kerr black holes.

Thermal surface analysis on high-rise building façades with neo-minimalist and modern style in Penang, Malaysia

Science.gov (United States)

Arab, Yasser; Hassan, Ahmad Sanusi; Qanaa, Bushra

2017-10-01

This research analyzed the façade thermal performance of high-rise buildings with modern and neo-minimalist architectural style. Four high-rise apartment buildings in Penang Island are selected as case studies for this research. The modern architectural style, which was popular during the 1970s to 1990s, nearly disregarded the cultural identity of the country and used the basic geometric shapes in the design. Conversely, the neo-minimalist style is the popular style from the 2010s up to the present. This style is a result of the "less is more" concept, which means using minimal applications to obtain an efficient design. The four selected case studies are as follows: Halaman Kristal 2 and Mutiara Idaman 1 with modern architectural style and Light Linear and Baystar apartments with neo-minimalist style. The research uses Fluke Ti20 thermal imager to capture thermal images of the west façade of the selected case studies on an hourly basis from 12:00 to 6:00 P.M. on March 15, 2017. Results confirm that the neo-minimalist façade elements, such as balconies and recessed walls, as well as other shading elements, are effective in improving the performance of façade shading. Notably, façade shading causes low surface temperature and provides cool indoor atmosphere during the day when the temperature is extremely high outside. Accordingly, this distinct feature partly explains the current popularity of the neo-minimalist architectural style.

Effect of metal nanoparticles on energy spectra and optical properties of peripheral light-harvesting LH2 complexes from photosynthetic bacteria

Energy Technology Data Exchange (ETDEWEB)

Goliney, I.Yu., E-mail: igoliney@kinr.kiev.ua [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine); Sugakov, V.I. [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine); Valkunas, L. [Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius (Lithuania); Department of Theoretical Physics, Vilnius University, Sauletekio 9, Build. 3, 10222 Vilnius (Lithuania); Vertsimakha, G.V. [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine)

2012-08-24

Highlights: Black-Right-Pointing-Pointer Excitons of light-harvesting complexes (LH2) hybridize with plasmon modes. Black-Right-Pointing-Pointer Light absorption of LH2 is enhanced by a metal nanoparticle. Black-Right-Pointing-Pointer Using nanoshells allows reaching resonance between molecular and plasmons. Black-Right-Pointing-Pointer Metal nanoparticles introduce additional channel of excitation decay. Black-Right-Pointing-Pointer Light-harvesting may gain from the proper positioning of nanoshells. -- Abstract: The paper explores the theoretical possibility of affecting optical spectra and the quantum yield of the energy transfer in the peripheral light-harvesting complexes (LH2) from photosynthetic bacteria by placing a metal nanoparticle or a nanoshell nearby. An increased probability of the excitonic transition in the LH2 arises due to the borrowing of the oscillator strength from surface plasmons of the metal particle or the nanoshell. While both absorption and quenching of the excitations increase in the vicinity to a metal nanoparticle, having opposite effects, the total yield of the excitation transfer to reaction centers is shown to grow in the certain range of parameters.

arXiv Light Primordial Exotic Compact Objects as All Dark Matter

CERN Document Server

Raidal, Martti; Vaskonen, Ville; Veermäe, Hardi

2018-06-13

The radiation emitted by horizonless exotic compact objects (ECOs), such as wormholes, 2-2-holes, fuzzballs, gravastars, boson stars, collapsed polymers, superspinars etc., is expected to be strongly suppressed when compared to the radiation of black holes. If large primordial curvature fluctuations collapse into such objects instead of black holes, they do not evaporate or evaporate much slower than black holes and could thus constitute all of the dark matter with masses below $M < 10^{-16}M_\\odot.$ We reevaluate the relevant experimental constraints for light ECOs in this mass range and show that very large new parameter space down to ECO masses $M\\sim 10\\,{\\rm TeV}$ opens up for light primordial dark matter. A new dedicated experimental program is needed to test this mass range of primordial dark matter.

Black TiO2 synthesized via magnesiothermic reduction for enhanced photocatalytic activity

Science.gov (United States)

Wang, Xiangdong; Fu, Rong; Yin, Qianqian; Wu, Han; Guo, Xiaoling; Xu, Ruohan; Zhong, Qianyun

2018-04-01

Utilizing solar energy for hydrogen evolution is a great challenge for its insufficient visible-light power conversion. In this paper, we report a facile magnesiothermic reduction of commercial TiO2 nanoparticles under Ar atmosphere and at 550 °C followed by acid treatment to synthesize reduced black TiO2 powders, which possesses a unique crystalline core-amorphous shell structure composed of disordered surface and oxygen vacancies and shows significantly improved optical absorption in the visible region. The unique core-shell structure and high absorption enable the reduced black TiO2 powders to exhibit enhanced photocatalytic activity, including splitting of water in the presence of Pt as a cocatalyst and degradation of methyl blue (MB) under visible light irradiation. Photocatalytic evaluations indicate that the oxygen vacancies play key roles in the catalytic process. The maximum hydrogen production rates are 16.1 and 163 μmol h-1 g-1 under the full solar wavelength range of light and visible light, respectively. This facile and versatile method could be potentially used for large scale production of colored TiO2 with remarkable enhancement in the visible light absorption and solar-driven hydrogen production.

Diversity and host interactions of emerging tomato begomoviruses in Brazil

NARCIS (Netherlands)

Ribeiro, S.G.

2006-01-01

Over the last decadestyle='color:black'>, thestyle='color:black'>prevalence and severity of tomato infecting begomoviruses have increased to epidemic proportions andconsequently,style='color:black'>begomoviruses became one of the major limitations for

Black Hole Hunters Set New Distance Record

Science.gov (United States)

2010-01-01

Astronomers using ESO's Very Large Telescope have detected, in another galaxy, a stellar-mass black hole much farther away than any other previously known. With a mass above fifteen times that of the Sun, this is also the second most massive stellar-mass black hole ever found. It is entwined with a star that will soon become a black hole itself. The stellar-mass black holes [1] found in the Milky Way weigh up to ten times the mass of the Sun and are certainly not be taken lightly, but, outside our own galaxy, they may just be minor-league players, since astronomers have found another black hole with a mass over fifteen times the mass of the Sun. This is one of only three such objects found so far. The newly announced black hole lies in a spiral galaxy called NGC 300, six million light-years from Earth. "This is the most distant stellar-mass black hole ever weighed, and it's the first one we've seen outside our own galactic neighbourhood, the Local Group," says Paul Crowther, Professor of Astrophysics at the University of Sheffield and lead author of the paper reporting the study. The black hole's curious partner is a Wolf-Rayet star, which also has a mass of about twenty times as much as the Sun. Wolf-Rayet stars are near the end of their lives and expel most of their outer layers into their surroundings before exploding as supernovae, with their cores imploding to form black holes. In 2007, an X-ray instrument aboard NASA's Swift observatory scrutinised the surroundings of the brightest X-ray source in NGC 300 discovered earlier with the European Space Agency's XMM-Newton X-ray observatory. "We recorded periodic, extremely intense X-ray emission, a clue that a black hole might be lurking in the area," explains team member Stefania Carpano from ESA. Thanks to new observations performed with the FORS2 instrument mounted on ESO's Very Large Telescope, astronomers have confirmed their earlier hunch. The new data show that the black hole and the Wolf-Rayet star dance

Black hole how an idea abandoned by Newtonians, hated by Einstein, and gambled on by Hawking became loved

CERN Document Server

Bartusiak, Marcia

2015-01-01

For more than half a century, physicists and astronomers engaged in heated dispute over the possibility of black holes in the universe. The weirdly alien notion of a space-time abyss from which nothing escapes-not even light-seemed to confound all logic. This engrossing book tells the story of the fierce black hole debates and the contributions of Einstein and Hawking and other leading thinkers who completely altered our view of the universe. Renowned science writer Marcia Bartusiak shows how the black hole helped revive Einstein's greatest achievement, the general theory of relativity, after decades during which it had been pushed into the shadows. Not until astronomers discovered such surprising new phenomena as neutron stars and black holes did the once-sedate universe transform into an Einsteinian cosmos, filled with sources of titanic energy that can be understood only in the light of relativity. This book celebrates the hundredth anniversary of general relativity, uncovers how the black hole really got ...

Key characteristics of different management styles

OpenAIRE

AGADZHANYAN A.S.

2015-01-01

The article reveals main management styles practiсed by managers all over the world. The author considers key characteristics of management styles, conditions of their using. The paper analyzes cultural differences in management styles in the West and in the East.

Microlensing Signature of Binary Black Holes

Science.gov (United States)

Schnittman, Jeremy; Sahu, Kailash; Littenberg, Tyson

2012-01-01

We calculate the light curves of galactic bulge stars magnified via microlensing by stellar-mass binary black holes along the line-of-sight. We show the sensitivity to measuring various lens parameters for a range of survey cadences and photometric precision. Using public data from the OGLE collaboration, we identify two candidates for massive binary systems, and discuss implications for theories of star formation and binary evolution.

In-vacuum scattered light reduction with black cupric oxide surfaces for sensitive fluorescence detection.

Science.gov (United States)

Norrgard, E B; Sitaraman, N; Barry, J F; McCarron, D J; Steinecker, M H; DeMille, D

2016-05-01

We demonstrate a simple and easy method for producing low-reflectivity surfaces that are ultra-high vacuum compatible, may be baked to high temperatures, and are easily applied even on complex surface geometries. Black cupric oxide (CuO) surfaces are chemically grown in minutes on any copper surface, allowing for low-cost, rapid prototyping, and production. The reflective properties are measured to be comparable to commercially available products for creating optically black surfaces. We describe a vacuum apparatus which uses multiple blackened copper surfaces for sensitive, low-background detection of molecules using laser-induced fluorescence.

In search of the black swans

Science.gov (United States)

Buchanan, Mark

2009-04-01

In 1890 an electricity company enticed the German physicist Max Planck to help it in its efforts to make more efficient light bulbs. Planck, as a theorist, naturally started with the fundamentals and soon became enmeshed in the thorny problem of explaining the spectrum of black-body radiation, which he eventually did by introducing the idea - a "purely formal" assumption, as he then considered it - that electromagnetic energy can only be emitted or absorbed in discrete quanta. The rest is history. Electric light bulbs and mathematical necessity led Planck to discover quantum theory and to kick start the most significant scientific revolution of the 20th century.

Strategic Style in Pared-Down Poker

Science.gov (United States)

Burns, Kevin

This chapter deals with the manner of making diagnoses and decisions, called strategic style, in a gambling game called Pared-down Poker. The approach treats style as a mental mode in which choices are constrained by expected utilities. The focus is on two classes of utility, i.e., money and effort, and how cognitive styles compare to normative strategies in optimizing these utilities. The insights are applied to real-world concerns like managing the war against terror networks and assessing the risks of system failures. After "Introducing the Interactions" involved in playing poker, the contents are arranged in four sections, as follows. "Underpinnings of Utility" outlines four classes of utility and highlights the differences between them: economic utility (money), ergonomic utility (effort), informatic utility (knowledge), and aesthetic utility (pleasure). "Inference and Investment" dissects the cognitive challenges of playing poker and relates them to real-world situations of business and war, where the key tasks are inference (of cards in poker, or strength in war) and investment (of chips in poker, or force in war) to maximize expected utility. "Strategies and Styles" presents normative (optimal) approaches to inference and investment, and compares them to cognitive heuristics by which people play poker--focusing on Bayesian methods and how they differ from human styles. The normative strategy is then pitted against cognitive styles in head-to-head tournaments, and tournaments are also held between different styles. The results show that style is ergonomically efficient and economically effective, i.e., style is smart. "Applying the Analysis" explores how style spaces, of the sort used to model individual behavior in Pared-down Poker, might also be applied to real-world problems where organizations evolve in terror networks and accidents arise from system failures.

Leadership = Communication? The Relations of Leaders' Communication Styles with Leadership Styles, Knowledge Sharing and Leadership Outcomes.

Science.gov (United States)

de Vries, Reinout E; Bakker-Pieper, Angelique; Oostenveld, Wyneke

2010-09-01

PURPOSE: The purpose of this study was to investigate the relations between leaders' communication styles and charismatic leadership, human-oriented leadership (leader's consideration), task-oriented leadership (leader's initiating structure), and leadership outcomes. METHODOLOGY: A survey was conducted among 279 employees of a governmental organization. The following six main communication styles were operationalized: verbal aggressiveness, expressiveness, preciseness, assuredness, supportiveness, and argumentativeness. Regression analyses were employed to test three main hypotheses. FINDINGS: In line with expectations, the study showed that charismatic and human-oriented leadership are mainly communicative, while task-oriented leadership is significantly less communicative. The communication styles were strongly and differentially related to knowledge sharing behaviors, perceived leader performance, satisfaction with the leader, and subordinate's team commitment. Multiple regression analyses showed that the leadership styles mediated the relations between the communication styles and leadership outcomes. However, leader's preciseness explained variance in perceived leader performance and satisfaction with the leader above and beyond the leadership style variables. IMPLICATIONS: This study offers potentially invaluable input for leadership training programs by showing the importance of leader's supportiveness, assuredness, and preciseness when communicating with subordinates. ORIGINALITY/VALUE: Although one of the core elements of leadership is interpersonal communication, this study is one of the first to use a comprehensive communication styles instrument in the study of leadership.

Drifting black aurorae?

International Nuclear Information System (INIS)

Schoute-Vanneck, H.; Scourfield, M.W.J.; Nielsen, E.

1990-01-01

Characteristics of eastward drifting forms, previously described in the literature as black aurorae, have been identified in low-light level TV camera data. The TV field of view was within the field of view of STARE and that of an all-sky camera. On the basis of these observations the authors propose that these auroral forms are a manifestation of folds or waves on the borders of auroral bands propagating along the dark regions between neighboring auroral bands. Conditions under which the folds or waves occur are compatible with their formation by the Kelvin-Helmholtz electrostatic instability

Cognitive Style: Individual Differences.

Science.gov (United States)

Saracho, Olivia N.

1989-01-01

A literature review describes several dimensions of cognitive styles in an effort to illustrate individual stylistic differences. Discusses the field dependence-independence dimension, taking into account age, sex, and cultural differences. Suggests that cognitive style theory needs to be structured in a broader theoretical framework. (NH)

LIFE-STYLE SEGMENTATION WITH TAILORED INTERVIEWING

NARCIS (Netherlands)

KAMAKURA, WA; WEDEL, M

The authors present a tailored interviewing procedure for life-style segmentation. The procedure assumes that a life-style measurement instrument has been designed. A classification of a sample of consumers into life-style segments is obtained using a latent-class model. With these segments, the

Chandra Sees Remarkable Eclipse of Black Hole

Science.gov (United States)

2007-04-01

A remarkable eclipse of a supermassive black hole and the hot gas disk around it has been observed with NASA's Chandra X-ray Observatory. This eclipse has allowed two key predictions about the effects of supermassive black holes to be tested. Just as eclipses of the Sun and moon give astronomers rare opportunities to learn about those objects, an alignment in a nearby galaxy has provided a rare opportunity to investigate a supermassive black hole. Illustrations of Black Hole Eclipse Illustrations of Black Hole Eclipse The supermassive black hole is located in NGC 1365, a galaxy 60 million light years from Earth. It contains a so called active galactic nucleus, or AGN. Scientists believe that the black hole at the center of the AGN is fed by a steady stream of material, presumably in the form of a disk. Material just about to fall into a black hole should be heated to millions of degrees before passing over the event horizon, or point of no return. The disk of gas around the central black hole in NGC 1365 produces copious X-rays but is much too small to resolve directly with a telescope. However, the disk was eclipsed by an intervening cloud, so observation of the time taken for the disk to go in and out of eclipse allowed scientists to estimate the size of the disk. Black Hole Animation Black Hole Animation "For years we've been struggling to confirm the size of this X-ray structure," said Guido Risaliti of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass, and the Italian Institute of Astronomy (INAF). "This serendipitous eclipse enabled us to make this breakthrough." The Chandra team directly measured the size of the X-ray source as about seven times the distance between the Sun and the Earth. That means the source of X-rays is about 2 billion times smaller than the host galaxy and only about 10 times larger than the estimated size of the black hole's event horizon, consistent with theoretical predictions. Chandra X-ray Image of NGC 1365

Parenting styles and eating disorders.

Science.gov (United States)

Jáuregui Lobera, I; Bolaños Ríos, P; Garrido Casals, O

2011-10-01

The aim of the study was to analyse the parental bonding profiles in patients with eating disorders (ED), as well as the relationship among the different styles of parenting and some psychological and psychopathological variables. In addition, the association between the perceived parental bonding and different coping strategies was analysed. Perception of parenting styles was analysed in a sample of 70 ED patients. The Parental Bonding Instrument, Self-Esteem Scale of Rosenberg, Coping Strategies Inventory, State-Trait Anxiety Inventory, Beck Depression Inventory and Eating Disorders Inventory-2 were used. Kruskal-Wallis test (comparisons), Spearman correlation coefficients (association among different variables) and χ(2)-test (parental bonding profiles differences) were applied. The stereotyped style among ED patients is low care-high control during the first 16 years, and the same can be said about current styles of the mothers. Between 8.6% and 12.9% of the patients perceive their parents' styles as neglectful. The neglectful parenting is the style mainly involved in the specific ED symptoms as drive for thinness, body dissatisfaction and bulimia. In order to achieve a better balanced parents' role during the treatment, it would be necessary to improve the role of the mothers as caregivers, decreasing their role mainly based on the overprotection. © 2011 Blackwell Publishing.

Codependency and Parenting Styles.

Science.gov (United States)

Fischer, Judith L.; Crawford, Duane W.

1992-01-01

College students (n=175) reported the parenting style of their mother and father and completed a scale assessing their own level of codependency. Parenting style of the father (uninvolved, permissive, authoritarian, or democratic) was related to offspring codependency. Both sons and daughters of authoritarian fathers had higher levels of…

Ghost Remains After Black Hole Eruption

Science.gov (United States)

2009-05-01

NASA's Chandra X-ray Observatory has found a cosmic "ghost" lurking around a distant supermassive black hole. This is the first detection of such a high-energy apparition, and scientists think it is evidence of a huge eruption produced by the black hole. This discovery presents astronomers with a valuable opportunity to observe phenomena that occurred when the Universe was very young. The X-ray ghost, so-called because a diffuse X-ray source has remained after other radiation from the outburst has died away, is in the Chandra Deep Field-North, one of the deepest X-ray images ever taken. The source, a.k.a. HDF 130, is over 10 billion light years away and existed at a time 3 billion years after the Big Bang, when galaxies and black holes were forming at a high rate. "We'd seen this fuzzy object a few years ago, but didn't realize until now that we were seeing a ghost", said Andy Fabian of the Cambridge University in the United Kingdom. "It's not out there to haunt us, rather it's telling us something - in this case what was happening in this galaxy billions of year ago." Fabian and colleagues think the X-ray glow from HDF 130 is evidence for a powerful outburst from its central black hole in the form of jets of energetic particles traveling at almost the speed of light. When the eruption was ongoing, it produced prodigious amounts of radio and X-radiation, but after several million years, the radio signal faded from view as the electrons radiated away their energy. HDF 130 Chandra X-ray Image of HDF 130 However, less energetic electrons can still produce X-rays by interacting with the pervasive sea of photons remaining from the Big Bang - the cosmic background radiation. Collisions between these electrons and the background photons can impart enough energy to the photons to boost them into the X-ray energy band. This process produces an extended X-ray source that lasts for another 30 million years or so. "This ghost tells us about the black hole's eruption long after

FEASTING BLACK HOLE BLOWS BUBBLES

Science.gov (United States)

2002-01-01

A monstrous black hole's rude table manners include blowing huge bubbles of hot gas into space. At least, that's the gustatory practice followed by the supermassive black hole residing in the hub of the nearby galaxy NGC 4438. Known as a peculiar galaxy because of its unusual shape, NGC 4438 is in the Virgo Cluster, 50 million light-years from Earth. These NASA Hubble Space Telescope images of the galaxy's central region clearly show one of the bubbles rising from a dark band of dust. The other bubble, emanating from below the dust band, is barely visible, appearing as dim red blobs in the close-up picture of the galaxy's hub (the colorful picture at right). The background image represents a wider view of the galaxy, with the central region defined by the white box. These extremely hot bubbles are caused by the black hole's voracious eating habits. The eating machine is engorging itself with a banquet of material swirling around it in an accretion disk (the white region below the bright bubble). Some of this material is spewed from the disk in opposite directions. Acting like high-powered garden hoses, these twin jets of matter sweep out material in their paths. The jets eventually slam into a wall of dense, slow-moving gas, which is traveling at less than 223,000 mph (360,000 kph). The collision produces the glowing material. The bubbles will continue to expand and will eventually dissipate. Compared with the life of the galaxy, this bubble-blowing phase is a short-lived event. The bubble is much brighter on one side of the galaxy's center because the jet smashed into a denser amount of gas. The brighter bubble is 800 light-years tall and 800 light-years across. The observations are being presented June 5 at the American Astronomical Society meeting in Rochester, N.Y. Both pictures were taken March 24, 1999 with the Wide Field and Planetary Camera 2. False colors were used to enhance the details of the bubbles. The red regions in the picture denote the hot gas

Schwarzschild black hole in the background of the Einstein universe: some physical effects

International Nuclear Information System (INIS)

Ramachandra, B S; Vishveshwara, C V

2002-01-01

A prototype of an asymptotically non-flat black hole spacetime is that of a Schwarzschild black hole in the background of the Einstein universe, which is a special case of the representation of a black hole in a cosmological background given by Vaidya. Recently, this spacetime has been studied in detail by Nayak et al. They constructed a composite spacetime called the Vaidya-Einstein-Schwarzschild (VES) spacetime. We investigate some of the physical effects inherent to this spacetime. We carry out a background-black hole decomposition of the spacetime in order to separate out the effects due to the background spacetime and the black hole. The physical effects we study include the classical tests - the gravitational redshift, perihelion precession and light bending - and circular geodesics. A detailed classification of geodesics, in general, is also given

Are Students' Learning Styles Discipline Specific?

Science.gov (United States)

Jones, Cheryl; Reichard, Carla; Mokhtari, Kouider

2003-01-01

This study examines the extent to which community college students' learning style preferences vary as a function of discipline. Reports significant differences in students' learning style preferences across disciplines, but not by gender. Adds that student learning style preferences varied by academic performance as measured by gender. Discusses…

Profiling & Utilizing Learning Style.

Science.gov (United States)

Keefe, James W., Ed.

The purpose of the National Association of Secondary School Principals (NASSP) Learning Style Profile is to provide educators with a well-validated and easy-to-use instrument for diagnosing the cognitive styles, perceptual response tendencies, and study/instructional preferences of middle level and senior high school students. The Learning Style…

QPOs from Random X-ray Bursts around Rotating Black Holes

Science.gov (United States)

Kukumura, Keigo; Kazanas, Demosthenes; Stephenson, Gordon

2009-01-01

We continue our earlier studies of quasi-periodic oscillations (QPOs) in the power spectra of accreting, rapidly-rotating black holes that originate from the geometric 'light echoes' of X-ray flares occurring within the black hole ergosphere. Our present work extends our previous treatment to three-dimensional photon emission and orbits to allow for arbitrary latitudes in the positions of the distant observers and the X-ray sources in place of the mainly equatorial positions and photon orbits of the earlier consideration. Following the trajectories of a large number of photons we calculate the response functions of a given geometry and use them to produce model light curves which we subsequently analyze to compute their power spectra and autocorrelation functions. In the case of an optically-thin environment, relevant to advection-dominated accretion flows, we consistently find QPOs at frequencies of order of approximately kHz for stellar-mass black hole candidates while order of approximately mHz for typical active galactic nuclei (approximately equal to 10(exp 7) solar mass) for a wide range of viewing angles (30 degrees to 80 degrees) from X-ray sources predominantly concentrated toward the equator within the ergosphere. As in out previous treatment, here too, the QPO signal is produced by the frame-dragging of the photons by the rapidly-rotating black hole, which results in photon 'bunches' separated by constant time-lags, the result of multiple photon orbits around the hole. Our model predicts for various source/observer configurations the robust presence of a new class of QPOs, which is inevitably generic to curved spacetime structure in rotating black hole systems.

Magnetic Origin of Black Hole Winds Across the Mass Scale

Science.gov (United States)

Fukumura, Keigo; Kazanas, Demosthenes; Shrader, Chris; Behar, Ehud; Tombesi, Francesco; Contopoulos, Ioannis

2017-01-01

Black hole accretion disks appear to produce invariably plasma outflows that result in blue-shifted absorption features in their spectra. The X-ray absorption-line properties of these outflows are quite diverse, ranging in velocity from non-relativistic (approx. 300 km/sec) to sub-relativistic (approx. 0.1c where c is the speed of light) and a similarly broad range in the ionization states of the wind plasma. We report here that semi-analytic, self-similar magnetohydrodynamic (MHD) wind models that have successfully accounted for the X-ray absorber properties of supermassive black holes, also fit well the high-resolution X-ray spectrum of the accreting stellar-mass black hole, GRO J1655-40. This provides an explicit theoretical argument of their MHD origin (aligned with earlier observational claims) and supports the notion of a universal magnetic structure of the observed winds across all known black hole sizes.

Gravitational radiation from the radial infall of highly relativistic point particles into Kerr black holes

International Nuclear Information System (INIS)

Cardoso, Vitor; Lemos, Jose P.S.

2003-01-01

In this paper, we consider the gravitational radiation generated by the collision of highly relativistic particles with rotating Kerr black holes. We use the Sasaki-Nakamura formalism to compute the waveform, energy spectra, and total energy radiated during this process. We show that the gravitational spectrum for high-energy collisions has definite characteristic universal features, which are independent of the spin of the colliding objects. We also discuss the possible connections between these results and black-hole-black-hole collisions at the speed of light. Our results show that during the high-speed collision of a nonrotating hole with a rotating one, at most 35% of the total energy can get converted into gravitational waves. This 35% efficiency occurs only in the most optimistic situation, that of a zero impact parameter collision, along the equatorial plane, with an almost extreme Kerr black hole. In the general situation, the total gravitational energy radiated is expected to be much less, especially if the impact parameter increases. Thus, if one is able to produce black holes at the CERN Large Hadron Collider, at most 35% of the partons' energy should be emitted during the so-called balding phase. This energy will be missing, since we do not have gravitational wave detectors able to measure such amplitudes. The collision at the speed of light between one rotating black hole and a nonrotating one or two rotating black holes turns out to be the most efficient gravitational wave generator in the Universe

Enhanced light absorption due to the mixing state of black carbon in fresh biomass burning emissions

Science.gov (United States)

Wang, Qiyuan; Cao, Junji; Han, Yongming; Tian, Jie; Zhang, Yue; Pongpiachan, Siwatt; Zhang, Yonggang; Li, Li; Niu, Xinyi; Shen, Zhenxing; Zhao, Zhuzi; Tipmanee, Danai; Bunsomboonsakul, Suratta; Chen, Yang; Sun, Jian

2018-05-01

A lack of information on the radiative effects of refractory black carbon (rBC) emitted from biomass burning is a significant gap in our understanding of climate change. A custom-made combustion chamber was used to simulate the open burning of crop residues and investigate the impacts of rBC size and mixing state on the particles' optical properties. Average rBC mass median diameters ranged from 141 to 162 nm for the rBC produced from different types of crop residues. The number fraction of thickly-coated rBC varied from 53 to 64%, suggesting that a majority of the freshly emitted rBC were internally mixed. By comparing the result of observed mass absorption cross-section to that calculated with Mie theory, large light absorption enhancement factors (1.7-1.9) were found for coated particles relative to uncoated cores. These effects were strongly positively correlated with the percentage of coated particles but independent of rBC core size. We suggest that rBC from open biomass burning may have strong impact on air pollution and radiative forcing immediately after their production.

Learning Styles and Continuing Medical Education.

Science.gov (United States)

Van Voorhees, Curtis; And Others

1988-01-01

The Gregorc Style Delineator--Word Matrix was administered to 2,060 physicians in order to gain a better understanding of their participation in continuing medical education. The study showed that 63 percent preferred the concrete sequential learning style. Different style preferences may account for some of the apparent disparity between…

Learning styles and courseware design

OpenAIRE

Valley, Karen

1997-01-01

In this paper we examine how (courseware) can accommodate differences in preferred learning style. A review of the literature on learning styles is followed by a discussion of the implications of being able to accurately classify learners, and key issues that must be addressed are raised. We then present two courseware design solutions that take into account individual learning‐style preference: the first follows on from traditional research in this area and assumes that learners can be class...

Advertising styles in different cultures

OpenAIRE

Krasulja Nevena

2003-01-01

Modern consumer is inhabitant of a "Global Village" as well as of its own national culture which largely influences his creation of a system of values, beliefs and style of life in general. According to adopted values and styles, consumers from different cultures have different buying behavior, different needs and preferences related to a product and they have their favorite advertising styles. As advertising reflects culture, symbols and rituals which are used are even more emphasized and st...

ONTOLOGY-DRIVEN TOOL FOR UTILIZING PROGRAMMING STYLES

Directory of Open Access Journals (Sweden)

Nikolay Sidorov

2017-07-01

Full Text Available Activities of a programmer will be more effective and the software will be more understandable when within the process of software development, programming styles (standards are used, providing clarity of software texts. Purpose: In this research, we present the tool for the realization of new ontology-based methodology automated reasoning techniques for utilizing programming styles. In particular, we focus on representing programming styles in the form of formal ontologies, and study how description logic reasoner can assist programmers in utilizing programming standards. Our research hypothesis is as follows: ontological representation of programming styles can provide additional benefits over existing approaches in utilizing programmer of programming standards. Our research goal is to develop a tool to support the ontology-based utilizing programming styles. Methods: ontological representation of programming styles; object-oriented programming; ontology-driven utilizing of programming styles. Results: the architecture was obtained and the tool was developed in the Java language, which provide tool support of ontology-driven programming styles application method. On the example of naming of the Java programming language standard, features of implementation and application of the tool are provided. Discussion: application of programming styles in coding of program; lack of automated tools for the processes of programming standards application; tool based on new method of ontology-driven application of programming styles; an example of the implementation of tool architecture for naming rules of the Java language standard.

Green technology as a strategy in managing the black spots in Siak Highway, Indonesia

Science.gov (United States)

Sandhyavitri, A.; Wira, J.; Martin, A.

2018-04-01

It was identified that the total traffic accidents in the highway section of Siak, Indonesia within the period of 2011 to 2015 were 1,208 events (2 accidents per 3 days). This accidents figure were considered relatively high and it need to mitigate. The aim of this research are to; (i) analyze the location of Black Spot in the Siak highway, and (ii) drawn a strategy reducing the traffic accidents based on green technology. This study identified that the black spot area was located in the STA 44 + 050 (with a value of the weighted index was 86 and an accident severity rate was 6.21), these values were relatively high. The road horizontal alignment condition at this location was highlighted as a sub-standard high way, consists of low visibility, numerous turning pads, minimum road signs, and minimum road shoulders width. The technical strategy was then drawn as follow; conducting regular road rehabilitation and maintenance, equipping road markings and the street lights as well as road safety facilities based on the green technology such as solar cell traffic lights, solar cell street lights and deploying police statues in reducing traffic accidents within the black spot areas.

Gyromagnetic ratio of charged Kerr-anti-de Sitter black holes

International Nuclear Information System (INIS)

Aliev, Alikram N

2007-01-01

We examine the gyromagnetic ratios of rotating and charged AdS black holes in four and higher spacetime dimensions. We compute the gyromagnetic ratio for Kerr-AdS black holes with an arbitrary electric charge in four dimensions and show that it corresponds to g = 2 irrespective of the AdS nature of the spacetime. We also compute the gyromagnetic ratio for Kerr-AdS black holes with a single angular momentum and with a test electric charge in all higher dimensions. The gyromagnetic ratio crucially depends on the dimensionless ratio of the rotation parameter to the curvature radius of the AdS background. At the critical limit, when the boundary Einstein universe is rotating at the speed of light, it exhibits a striking feature leading to g 2 regardless of the spacetime dimension. Next, we extend our consideration to include the exact metric for five-dimensional rotating charged black holes in minimal gauged supergravity. We show that the value of the gyromagnetic ratio found in the 'test-charge' approach remains unchanged for these black holes

Decision Styles and Rationality: An Analysis of the Predictive Validity of the General Decision-Making Style Inventory

Science.gov (United States)

Curseu, Petru Lucian; Schruijer, Sandra G. L.

2012-01-01

This study investigates the relationship between the five decision-making styles evaluated by the General Decision-Making Style Inventory, indecisiveness, and rationality in decision making. Using a sample of 102 middle-level managers, the results show that the rational style positively predicts rationality in decision making and negatively…

Child Temperament, Maternal Feeding Practices, and Parenting Styles and Their Influence on Obesogenic Behaviors in Hispanic Preschool Children.

Science.gov (United States)

Innella, Nancy; McNaughton, Diane; Schoeny, Michael; Tangney, Christy; Breitenstein, Susan; Reed, Monique; Wilbur, Joellen

2018-01-01

Although obesogenic behaviors (physical activity and/or sedentary behavior and dietary intake) are known predictors of childhood weight status, little is known about mother and child behaviors contributing to obesogenic behaviors and obesity in Hispanic preschool children, whose obesity rate is higher than in non-Hispanic Whites and non-Hispanic Blacks. The purpose of this cross-sectional, descriptive study was to examine relationships among child temperament, maternal behaviors (feeding practices and parenting style), child obesogenic behaviors, and child weight status in 100 Hispanic preschool children. Results showed that higher scores on the negative affectivity dimension of child temperament were associated with higher scores on the dimension of permissive parenting, and permissive parenting was associated with less time spent in sedentary behaviors ( B = -3.53, confidence interval [-7.52, -0.90]). Findings can guide school nurses in developing interventions that consider child temperament and parenting style to promote nonobesogenic behavior in Hispanic preschoolers.

Taking the Pulse of a Black Hole System

Science.gov (United States)

2011-01-01

Using two NASA X-ray satellites, astronomers have discovered what drives the "heartbeats" seen in the light from an unusual black hole system. These results give new insight into the ways that black holes can regulate their intake and severely curtail their growth. This study examined GRS 1915+105 (GRS 1915 for short), a binary system in the Milky Way galaxy containing a black hole about 14 times more massive than the Sun that is feeding off material from a companion star. As this material falls towards the black hole, it forms a swirling disk that emits X-rays. The black hole in GRS 1915 has been estimated to rotate at the maximum possible rate, allowing material in the inner disk to orbit very close to the black hole, at a radius only 20% larger than the event horizon, where the material travels at 50% the speed of light. Using the Chandra X-ray Observatory and the Rossi X-ray Timing Explorer (RXTE), researchers monitored this black hole system over a period of eight hours. As they watched, GRS 1915 gave off a short, bright pulse of X-ray light approximately every 50 seconds, varying in brightness by a factor of about three. This type of rhythmic cycle closely resembles an electrocardiogram of a human heart -- though at a slower pace. "Trying to understand the physics of this 'heartbeat state' is a little like trying to understand how a person's heart beats by watching changes in the blood flow through their veins," said Joey Neilsen, a graduate student at Harvard University, who presented these results from his dissertation at the American Astronomical Society (AAS) meeting in Seattle, Wash. It was previously known that GRS 1915 can develop such heartbeats when its mass consumption rate is very high. After monitoring it with the special combination of Chandra and RXTE, Neilsen and his collaborators realized that they could use the pulses to figure out what controls how much material the black hole consumes. "With each beat, the black hole pumps an enormous

Highly efficient white organic light-emitting devices consisting of undoped ultrathin yellow phosphorescent layer

Energy Technology Data Exchange (ETDEWEB)

Liu, Shengqiang [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Ma, Zhu; Zhao, Juan [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

2013-02-15

High-efficiency white organic light-emitting devices (WOLEDs) based on an undoped ultrathin yellow light-emitting layer and a doped blue light-emitting layer were demonstrated. While the thickness of blue light-emitting layer, formed by doping a charge-trapping phosphor, iridium(III) bis(4 Prime ,6 Prime -difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) in a wide bandgap host, was kept constant, the thickness of neat yellow emissive layer of novel phosphorescent material, bis[2-(4-tertbutylphenyl)benzothiazolato-N,C{sup 2 Prime }]iridium (acetylacetonate) [(t-bt){sub 2}Ir(acac)] was varied to optimize the device performance. The optimized device exhibited maximum luminance, current efficiency and power efficiency of 24,000 cd/m{sup 2} (at 15.2 V), 79.0 cd/A (at 1550 cd/m{sup 2}) and 40.5 lm/W (at 1000 cd/m{sup 2}), respectively. Besides, the white-light emission covered a wide range of visible spectrum, and the Commission Internationale de l'Eclairage coordinates were (0.32, 0.38) with a color temperature of 5800 K at 8 V. Moreover, high external quantum efficiency was also obtained in the high-efficiency WOLEDs. The performance enhancement was attributed to the proper thickness of (t-bt){sub 2}Ir(acac) layer that enabled adequate current density and enough phosphorescent dye to trap electrons. - Highlights: Black-Right-Pointing-Pointer Highly efficient WOLEDs based on two complementary layers were fabricated. Black-Right-Pointing-Pointer The yellow emissive layer was formed by utilizing undoping system. Black-Right-Pointing-Pointer The blue emissive layer was made by host-guest doping system. Black-Right-Pointing-Pointer The thickness of the yellow emissive layer was varied to make device optimization. Black-Right-Pointing-Pointer The optimized device achieved high power efficiency of 40.5 lm/W.

Parent Predictors of Adolescents' Explanatory Style

Science.gov (United States)

Vélez, Clorinda E.; Krause, Elizabeth D.; Brunwasser, Steven M.; Freres, Derek R.; Abenavoli, Rachel M.; Gillham, Jane E.

2015-01-01

The current study tested the prospective relations (6-month lag) between three aspects of the parent-child relationship at Time 1 (T1) and adolescents' explanatory styles at Time 2 (T2): caregiving behaviors, parents' explanatory style for their own negative events, and parents' explanatory style for their children's negative events. The sample…

Lifetime of ALD Al₂O₃ Passivated Black Silicon Nanostructured for Photovoltaic Applications

DEFF Research Database (Denmark)

Plakhotnyuk, Maksym; Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk

Black silicon nano-structures provide significant reduction of silicon surface reflection due to highly corrugated nano-structures with excellent light trapping properties. However, most recent RIE techniques for black silicon nano-structuring have one very important limitation for PV applications...

Decoration of BiOI quantum size nanoparticles with reduced graphene oxide in enhanced visible-light-driven photocatalytic studies

Energy Technology Data Exchange (ETDEWEB)

Liu Zhang, E-mail: liuzhang0126@126.com [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Xu Weicheng [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Fang Jianzhang, E-mail: fangjzh@scnu.edu.cn [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Xu Xiaoxin; Wu Shuxing; Zhu Ximiao; Chen Zehua [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer RGO/BiOI nanocomposites were synthesized by a reverse microemulsion method. Black-Right-Pointing-Pointer Quantum sized BiOI nanoparticles can be obtained by this approach. Black-Right-Pointing-Pointer Ascorbic acid was used as a reducing agent to reduce GO and seemed to be effective. Black-Right-Pointing-Pointer RGO/BiOI presented outstanding visible-light-induced photocatalytic performance. Black-Right-Pointing-Pointer Possible photocatalytic mechanism was proposed based on the experimental studies. - Abstract: Herein, a reverse microemulsion route was developed to synthesize bismuth oxyiodide (BiOI) nanocrystals and reduced graphene oxide (RGO) nanocomposites as a highly efficient photocatalyst, and both the formation of BiOI and the reduction of RGO were achieved in situ in microemulsions simultaneously at low temperature (60 Degree-Sign C). The uniform nanocrystal size and structure were indicated by XRD, TEM, and the reduction of GO by ascorbic acid was evidenced by FTIR, XPS, and Raman spectra techniques. The enhanced photoactivity of RGO/BiOI nanocomposites under visible light was attributed to improved light absorption and efficient charge separation and transportation.

Reading Processes and Parenting Styles.

Science.gov (United States)

Carreteiro, Rui Manuel; Justo, João Manuel; Figueira, Ana Paula

2016-08-01

Home literacy environment explains between 12 and 18.5 % of the variance of children's language skills. Although most authors agree that children whose parents encourage them to read tend to develop better and earlier reading skills, some authors consider that the impact of family environment in reading skills is overvalued. Probably, other variables of parent-child relationship, like parenting styles, might be relevant for this field. Nevertheless, no previous studies on the effect of parenting styles in literacy have been found. To analyze the role of parenting styles in the reading processes of children. Children's perceptions of parenting styles contribute significantly to the explanation of statistical variance of children's reading processes. 110 children (67 boys and 43 girls), aged between 7 and 11 years (M [Formula: see text] 9.22 and SD [Formula: see text] 1.14) from Portuguese schools answered to a socio-demographic questionnaire. To assess reading processes it was administered the Portuguese adaptation (Figueira et al. in press) of Bateria de Avaliação dos Processos Leitores-Revista (PROLEC-R). To assess the parenting styles Egna Minnen av Barndoms Uppfostran-parents (EMBU-P) and EMBU-C (children version) were administered. According to multiple hierarchical linear regressions, individual factors contribute to explain all reading tests of PROLEC-R, while family factors contribute to explain most of these tests. Regarding parenting styles, results evidence the explanatory power about grammatical structures, sentence comprehension and listening. Parenting styles have an important role in the explanation of higher reading processes (syntactic and semantic) but not in lexical processes, focused by main theories concerning dyslexia.

Black phosphorus-based one-dimensional photonic crystals and microcavities.

Science.gov (United States)

Kriegel, Ilka; Toffanin, Stefano; Scotognella, Francesco

2016-11-10

The latest achievements in the fabrication of thin layers of black phosphorus (BP), toward the technological breakthrough of a phosphorene atomically thin layer, are paving the way for their use in electronics, optics, and optoelectronics. In this work, we have simulated the optical properties of one-dimensional photonic structures, i.e., photonic crystals and microcavities, in which few-layer BP is one of the components. The insertion of the 5-nm black phosphorous layers leads to a photonic band gap in the photonic crystals and a cavity mode in the microcavity that is interesting for light manipulation and emission enhancement.

A Community Network of 100 Black Carbon Sensors

Science.gov (United States)

Preble, C.; Kirchstetter, T.; Caubel, J.; Cados, T.; Keeling, C.; Chang, S.

2017-12-01

We developed a low-cost black carbon sensor, field tested its performance, and then built and deployed a network of 100 sensors in West Oakland, California. We operated the network for 100 days beginning mid-May 2017 to measure spatially resolved black carbon concentrations throughout the community. West Oakland is a San Francisco Bay Area mixed residential and industrial community that is adjacent to regional port and rail yard facilities and surrounded by major freeways. As such, the community is affected by diesel particulate matter emissions from heavy-duty diesel trucks, locomotives, and ships associated with freight movement. In partnership with Environmental Defense Fund, the Bay Area Air Quality Management District, and the West Oakland Environmental Indicators Project, we deployed the black carbon monitoring network outside of residences and business, along truck routes and arterial streets, and at upwind locations. The sensor employs the filter-based light transmission method to measure black carbon and has good precision and correspondence with current commercial black carbon instruments. Throughout the 100-day period, each of the 100 sensors transmitted data via a cellular network. A MySQL database was built to receive and manage the data in real-time. The database included diagnostic features to monitor each sensor's operational status and facilitate the maintenance of the network. Spatial and temporal patterns in black carbon concentrations will be presented, including patterns around industrial facilities, freeways, and truck routes, as well as the relationship between neighborhood concentrations and the BAAQMD's monitoring site. Lessons learned during this first of its kind black carbon monitoring network will also be shared.

Conceptualizing On-the-Job Learning Styles

Science.gov (United States)

Berings, Marjolein G. M. C.; Poell, Rob F.; Simons, P. Robert-Jan

2005-01-01

The broad aims of this study are to gain insight into employees' on-the-job learning activities to help them improve their on-the-job learning. The authors define on-the-job learning styles and operationalize the concept to include both mental and overt learning styles and both interpersonal and intrapersonal learning styles. Organizations and…

Analytic information processing style in epilepsy patients.

Science.gov (United States)

Buonfiglio, Marzia; Di Sabato, Francesco; Mandillo, Silvia; Albini, Mariarita; Di Bonaventura, Carlo; Giallonardo, Annateresa; Avanzini, Giuliano

2017-08-01

Relevant to the study of epileptogenesis is learning processing, given the pivotal role that neuroplasticity assumes in both mechanisms. Recently, evoked potential analyses showed a link between analytic cognitive style and altered neural excitability in both migraine and healthy subjects, regardless of cognitive impairment or psychological disorders. In this study we evaluated analytic/global and visual/auditory perceptual dimensions of cognitive style in patients with epilepsy. Twenty-five cryptogenic temporal lobe epilepsy (TLE) patients matched with 25 idiopathic generalized epilepsy (IGE) sufferers and 25 healthy volunteers were recruited and participated in three cognitive style tests: "Sternberg-Wagner Self-Assessment Inventory", the C. Cornoldi test series called AMOS, and the Mariani Learning style Questionnaire. Our results demonstrate a significant association between analytic cognitive style and both IGE and TLE and respectively a predominant auditory and visual analytic style (ANOVA: p values <0,0001). These findings should encourage further research to investigate information processing style and its neurophysiological correlates in epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.

Management styles and motivation.

Science.gov (United States)

Shearer, Dana Ann

2012-01-01

According to a review of the current literature, common managerial styles are transformational, transactional, and laissez-faire. When managers expand their leadership skills to improve the staff's morale, they must use a combination of transformational leadership behaviors and transactional contingent rewards to maximize their effectiveness on employees. A motivation theory such as Herzberg and Maslow enhances employees' motivation, morale, and satisfaction. Being able to motivate, empower, and influence staff improves satisfaction and retention levels among the team. A manager's leadership style influences motivation, morale, and retention in staff. Leaders are influenced by their educational development and the organizational culture. Organizational culture has an impact on a manager's style, which is forwarded to their followers.

Conflict management styles in the health professions.

Science.gov (United States)

Sportsman, Susan; Hamilton, Patti

2007-01-01

The purpose of the study was to determine prevalent conflict management styles chosen by students in nursing and to contrast these styles with those chosen by students in allied health professions. The associations among the level of professional health care education and the style chosen were also determined. A convenience sample of 126 students in a comprehensive university completed the Thomas-Kilmann Conflict Mode Instrument (TKI), which requires respondents to choose behaviors most characteristic of their response to conflict and classifies these behaviors as one of five styles. There was no significant difference between the prevalent conflict management styles chosen by graduate and undergraduate nursing students and those in allied health. Some of the students were already licensed in their discipline; others had not yet taken a licensing exam. Licensure and educational level were not associated with choice of styles. Women and men had similar preferences. The prevalent style for nursing students was compromise, followed by avoidance. In contrast, avoidance, followed by compromise and accommodation, was the prevalent style for allied health students. When compared to the TKI norms, slightly more than one half of all participants chose two or more conflict management styles, commonly avoidance and accommodation at the 75th percentile or above. Only 9.8% of the participants chose collaboration at that level. Implications for nurse educators, researchers, and administrators are discussed.

Demystifying APA style.

Science.gov (United States)

Cuddy, Claudia M

2002-01-01

Many nursing schools and health care journals have adopted the Publication Manual of the American Psychological Association (APA stylebook) as their guide to achieve uniformity and consistency in manuscript preparation as well as in usage and writing style. Published in 2001, the fifth edition of the APA stylebook contains 440 pages and can overwhelm someone who tries to use it for the first time. This article delineates main points in the areas of manuscript preparation, reference lists, in-text citations, and style choices.

School Disciplinary Style and Adolescent Health.

Science.gov (United States)

Lau, Claudia; Wong, Mitchell; Dudovitz, Rebecca

2018-02-01

Parenting style is strongly associated with adolescent health. However, little is known about how school disciplinary style relates to health. We categorized adolescents' perceptions of their schools as authoritative, authoritarian, permissive, or neglectful, and test whether perceived school disciplinary style is associated with health. We analyze data from the RISE Up study (Reducing Health Inequities Through Social and Educational Change Follow-up), comprised of baseline (eighth grade) and 2-year follow-up surveys (10th grade) from 1,159 low-income minority adolescents in Los Angeles attending 157 schools. At 10th grade, students' ratings of school support and structure were used to categorize perceived school disciplinary style as authoritative (highest tertile for support and structure), authoritarian (low support, high structure), permissive (high support, low structure), neglectful (low on both dimensions), and average (middle tertile on either dimension). Mixed effects logistic regressions controlling for sociodemographic factors, parenting style, grades, and baseline health tested whether school disciplinary style was associated with substance use, violence, bullying, and depression symptoms. Risky behaviors varied by school disciplinary style. After adjusting for covariates, compared with an average school disciplinary style, a neglectful school was associated with higher odds of substance use (adjusted odds ratio [AOR] 2.3, p authoritative school was associated with lower odds of substance use (AOR .6, p = .049), violence (AOR .6, p = .03), and bullying (AOR .5, p = .001). Structured and supportive school environments may impact the health of vulnerable adolescents. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Parenting styles, feeding styles and food-related parenting practices in relation to toddlers' eating styles: A cluster-analytic approach

OpenAIRE

van der Horst, Klazine; Sleddens, Ester F. C.

2017-01-01

Introduction Toddlers? eating behaviors are influenced by the way parents interact with their children. The objective of this study was to explore how five major constructs of general parenting behavior cluster in parents of toddlers. These parenting clusters were further explored to see how they differed in the use of feeding strategies (i.e. feeding styles and food parenting practices) and by reported child eating styles. Methods An online survey with 1005 mothers/caregivers (legal guardian...

Attachment styles and contingencies of self-worth.

Science.gov (United States)

Park, Lora E; Crocker, Jennifer; Mickelson, Kristin D

2004-10-01

Previous research on attachment theory has focused on mean differences in level of self-esteem among people with different attachment styles. The present study examines the associations between attachment styles and different bases of self-esteem, or contingencies of self-worth, among a sample of 795 college students. Results showed that attachment security was related to basing self-worth on family support. Both the preoccupied attachment style and fearful attachment style were related to basing self-worth on physical attractiveness. The dismissing attachment style was related to basing self-worth less on others' approval, family support, and God's love.

Statistical Origin of Black Hole Entropy in Matrix Theory

International Nuclear Information System (INIS)

Lowe, D.A.

1998-01-01

The statistical entropy of black holes in matrix theory is considered. Assuming matrix theory is the discretized light-cone quantization of a theory with eleven-dimensional Lorentz invariance, we map the counting problem onto the original Gibbons-Hawking calculations of the thermodynamic entropy. copyright 1998 The American Physical Society

Newly Discovered Items of the Zoomorphic Style from the Left Bank of the Lower Dniester

Directory of Open Access Journals (Sweden)

Sinika Vitalij S.

2017-09-01

Full Text Available The article presents an overview of items corresponding to the Scythian zoomorphic style discovered at barbaric and ancient sites of the Northwestern Black Sea Region, and a publication of two new findings. They were discovered on the left bank of the Lower Dniester. The first item discovered at Parkany-II settlement is a fragment of a bronze horse plaque (its lower part crafted in the shape of a "rooster"-hippocampus. The other artifact discovered near Tokmazeya village also represents a horse plaque with an image of a cat predator's head. Presently, there are no counterparts of the images on these findings in the Northwestern Black Sea Region, which is the westmost periphery of the Scythian steppe culture. These fragments of horse apparel broaden our knowledge of the Scythian "bestiary" in the region. Besides, apart from the other items of material culture, the published findings confirm the presence of Scythian population at settlement sites, which contradicts the generally accepted opinion on the exclusively nomadic cattle breeding lifestyle of the Scythians in 5th –4th centuries B.C.

An Investigation of Decision Making Styles and the Five-Factor Personality Traits with Respect to Attachment Styles

Science.gov (United States)

Deniz, M. Engin

2011-01-01

The aim of this research is to investigate if the attachment styles significantly predict the decision self-esteem, decision making styles and five-factor personality traits. Subjects of the study were 567 students in total from different faculties of Selcuk University. The results of the study showed that the attachment styles of the students…

Eating disorder symptoms and parenting styles.

Science.gov (United States)

Haycraft, Emma; Blissett, Jackie

2010-02-01

This study aimed to examine associations between symptoms of eating disorders and parenting style, in a non-clinical sample. One hundred and five mothers completed self-report measures of eating disorder symptoms and parenting style. Higher levels of eating disorder symptoms were associated with more authoritarian and permissive parenting styles. Authoritative parenting was not significantly related to eating disorder symptoms. The findings demonstrate that eating disorder symptoms in non-clinical individuals are related to less adaptive parenting styles. These findings have potential implications for clinicians working with mothers with eating disorders. 2009 Elsevier Ltd. All rights reserved.

Chandra Reviews Black Hole Musical: Epic But Off-Key

Science.gov (United States)

2006-10-01

A gigantic sonic boom generated by a supermassive black hole has been found with NASA's Chandra X-ray Observatory, along with evidence for a cacophony of deep sound. This discovery was made by using data from the longest X-ray observation ever of M87, a nearby giant elliptical galaxy. M87 is centrally located in the Virgo cluster of galaxies and is known to harbor one of the Universe's most massive black holes. Scientists detected loops and rings in the hot, X-ray emitting gas that permeates the cluster and surrounds the galaxy. These loops provide evidence for periodic eruptions that occurred near the supermassive black hole, and that generate changes in pressure, or pressure waves, in the cluster gas that manifested themselves as sound. Chandra Low Energy X-ray Images of M87 Chandra Low Energy X-ray Images of M87 "We can tell that many deep and different sounds have been rumbling through this cluster for most of the lifetime of the Universe," said William Forman of the Harvard-Smithsonian Center for Astrophysics (CfA). The outbursts in M87, which happen every few million years, prevent the huge reservoir of gas in the cluster from cooling and forming many new stars. Without these outbursts and resultant heating, M87 would not be the elliptical galaxy it is today. "If this black hole wasn't making all of this noise, M87 could have been a completely different type of galaxy," said team member Paul Nulsen, also of the CfA, "possibly a huge spiral galaxy about 30 times brighter than the Milky Way." Chandra High Energy X-ray Image of M87 Chandra High Energy X-ray Image of M87 The outbursts result when material falls toward the black hole. While most of the matter is swallowed, some of it was violently ejected in jets. These jets are launched from regions close to the black hole (neither light nor sound can escape from the black hole itself) and push into the cluster's gas, generating cavities and sound which then propagate outwards. Chandra's M87 observations also

Conference: Seeing two black holes merge (with gravitational waves!) | 14 September | Uni Dufour

CERN Multimedia

2016-01-01

GW150914: the first direct observation of gravitational waves from the inspiral and merger of two black holes - Conference by Prof. Bruce Allen, Albert Einstein Institute Hannover.   "Seeing two black holes merge (with gravitational waves!)" Uni Dufour - Auditorium U300 Wednesday, 14 September at 7 p.m.   Bruce Allen. (Photo: ©F. Vinken/MPG) Abstract: On 14 September 2015, the advanced LIGO gravitational wave instruments detected the gravitational wave signal emitted as two black holes, about one billion light years away from Earth, made a final few orbits around each other then merged together. This was big news around the world, because scientists have tried to make such observations for more than half a century. Before they merged, the two black holes were about 29 and 36 times as massive as the sun; after the merger was complete, a single black hole about 62 times the sun's mass was left behind. I'll describe what black holes are, how they (...

From Rindler horizon to mini black holes at LHC

Energy Technology Data Exchange (ETDEWEB)

Ghaffary, Tooraj [Islamic Azad University, Department of Science, Shiraz Branch, Shiraz (Iran, Islamic Republic of)

2017-02-15

Recently researchers (A. Sepehri et al., Astrophys. Space Sci. 344, 79 (2013)) have considered the signature of superstring balls near mini black holes at LHC and calculate the information loss for these types of strings. Motivated by their work, we consider the evolution of events in high energy experiments from lower energies for which the Rindler horizon is formed to higher energies in which mini black holes and string balls are emerged. Extending the Gottesman and Preskill method to string theory, we find the information loss for excited strings ''string balls'' in mini black holes at LHC and calculate the information transformation from the collapsing matter to the state of outgoing Hawking radiation for strings. We come to the conclusion that information transformation for high energy strings is complete. Then the thermal distribution of excited strings near mini black holes at LHC is calculated. In order to obtain the total string cross section near black holes produced in proton-proton collision, we multiply the black hole production cross section by the thermal distribution of strings. It is observed that many high energy excited strings are produced near the event horizon of TeV black holes. These excited strings evaporate to standard model particles like Higgs boson and top quark at Hagedorn temperature. We derive the production cross section for these particles due to string ball decay at LHC and consider their decay to light particles like bottom quarks and gluons. (orig.)

The effects of additional black carbon on the albedo of Arctic sea ice: variation with sea ice type and snow cover

Directory of Open Access Journals (Sweden)

A. A. Marks

2013-07-01

Full Text Available The response of the albedo of bare sea ice and snow-covered sea ice to the addition of black carbon is calculated. Visible light absorption and light-scattering cross-sections are derived for a typical first-year and multi-year sea ice with both "dry" and "wet" snow types. The cross-sections are derived using data from a 1970s field study that recorded both reflectivity and light penetration in Arctic sea ice and snow overlying sea ice. The variation of absorption cross-section over the visible wavelengths suggests black carbon is the dominating light-absorbing impurity. The response of first-year and multi-year sea ice albedo to increasing black carbon, from 1 to 1024 ng g−1, in a top 5 cm layer of a 155 cm-thick sea ice was calculated using a radiative-transfer model. The albedo of the first-year sea ice is more sensitive to additional loadings of black carbon than the multi-year sea ice. An addition of 8 ng g−1 of black carbon causes a decrease to 98.7% of the original albedo for first-year sea ice compared to a decrease to 99.7% for the albedo of multi-year sea ice, at a wavelength of 500 nm. The albedo of sea ice is surprisingly unresponsive to additional black carbon up to 100 ng g−1 . Snow layers on sea ice may mitigate the effects of black carbon in sea ice. Wet and dry snow layers of 0.5, 1, 2, 5 and 10 cm depth were added onto the sea ice surface. The albedo of the snow surface was calculated whilst the black carbon in the underlying sea ice was increased. A layer of snow 0.5 cm thick greatly diminishes the effect of black carbon in sea ice on the surface albedo. The albedo of a 2–5 cm snow layer (less than the e-folding depth of snow is still influenced by the underlying sea ice, but the effect of additional black carbon in the sea ice is masked.

Relation of parenting styles, feeding styles and feeding practices to child overweight and obesity. Direct and moderated effects.

Science.gov (United States)

Hubbs-Tait, Laura; Dickin, Katherine L; Sigman-Grant, Madeleine; Jahns, Lisa; Mobley, Amy R

2013-12-01

The purpose of this study was to evaluate the direct and interacting relations of parenting styles, feeding styles, and feeding practices to child overweight and obesity. Participants were 144 mothers and children under 6 years of age. Mothers completed questionnaires about parenting and feeding styles and feeding practices. Researchers weighed and measured mothers and children or obtained measurements from a recent health report. Feeding practices were not directly related to child weight status. Compared to the uninvolved feeding style, authoritative and authoritarian feeding style categories were linked to lower odds of overweight. Feeding practices interacted with authoritative and authoritarian parenting styles to predict obesity: (1) healthful modeling was associated with 61% (OR = 0.39) reduced odds of obesity in children of authoritative mothers but with 55% (OR = 1.55) increased odds in children of non-authoritative mothers and (2) covert control was linked to 156% (OR = 2.56) increased odds of obesity in children of authoritarian mothers but with 51% (OR = 0.49) decreased odds in children of non-authoritarian mothers. Healthful modeling interacted with feeding style demandingness to predict overweight and with responsiveness to predict obesity. Findings suggest the need for research and interventions on mechanisms mediating between feeding practices and obesity in families characterized by non-authoritative parenting styles. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Precocious Supermassive Black Holes Challenge Theories

Science.gov (United States)

2004-11-01

NASA's Chandra X-ray Observatory has obtained definitive evidence that a distant quasar formed less than a billion years after the Big Bang contains a fully-grown supermassive black hole generating energy at the rate of twenty trillion Suns. The existence of such massive black holes at this early epoch of the Universe challenges theories of the formation of galaxies and supermassive black holes. Astronomers Daniel Schwartz and Shanil Virani of the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA observed the quasar, known as SDSSp J1306, which is 12.7 billion light years away. Since the Universe is estimated to be 13.7 billion years old, we see the quasar as it was a billion years after the Big Bang. They found that the distribution of X-rays with energy, or X-ray spectrum, is indistinguishable from that of nearby, older quasars. Likewise, the relative brightness at optical and X-ray wavelengths of SDSSp J1306 was similar to that of the nearby group of quasars. Optical observations suggest that the mass of the black hole is about a billion solar masses. Illustration of Quasar SDSSp J1306 Illustration of Quasar SDSSp J1306 Evidence of another early-epoch supermassive black hole was published previously by a team of scientists from the California Institute of Technology and the United Kingdom using the XMM-Newton X-ray satellite. They observed the quasar SDSSp J1030 at a distance of 12.8 billion light years and found essentially the same result for the X-ray spectrum as the Smithsonian scientists found for SDSSp J1306. Chandra's precise location and spectrum for SDSSp J1306 with nearly the same properties eliminate any lingering uncertainty that precocious supermassive black holes exist. "These two results seem to indicate that the way supermassive black holes produce X-rays has remained essentially the same from a very early date in the Universe," said Schwartz. "This implies that the central black hole engine in a massive galaxy was formed very soon

The vacuum pyrolysis of used tires. End-uses for oil and carbon black products

Energy Technology Data Exchange (ETDEWEB)

Roy, C.; Chaala, A.; Darmstadt, H. [Institut Pyrovac Inc., Parc Technologique du Quebec Metropolitain, rue Franquet, Sainte-Foy (Canada)

1999-07-01

By vacuum pyrolysis, the rubber portion of used tires is transformed into oil and gas and the carbon black filler is recovered as pyrolytic carbon black (CB{sub P}). Several commercial applications for the different products have been investigated and are reported in this article. CB{sub P} surface chemistry and activity are similar to those of commercial carbon blacks. Therefore, CB{sub P} has the potential to replace commercial carbon black grades in certain rubber applications. CB{sub P} was successfully tested as a filler in road pavement. The total pyrolytic oil can be used as a liquid fuel. The oil can also be distilled into different fractions: a light, a middle distillate and a heavy fraction. The light fraction was positively tested as a gasoline additive. Furthermore, this fraction contains valuable chemicals such as d,l-limonene. The middle fraction was successfully tested as a plasticizer in rubbers. The heavy fraction represents a good-quality feedstock for the production of coke and can also be used in road pavements. The pyrolytic gas can be used as a make-up heat source for the pyrolysis process

Black Silicon Solar Cells with Black Ribbons

DEFF Research Database (Denmark)

Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io

2016-01-01

We present the combination of mask-less reactive ion etch (RIE) texturing and blackened interconnecting ribbons as a method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon made by mask-less reactive ion etching has total, average...... in the range 15.7-16.3%. The KOH-textured reference cell had an efficiency of 17.9%. The combination of black Si and black interconnecting ribbons may result in aesthetic, all-black panels based on conventional, front-contacted silicon solar cells....... reflectance below 0.5% across a 156x156 mm2 silicon (Si) wafer. Black interconnecting ribbons were realized by oxidizing copper resulting in reflectance below 3% in the visible wavelength range. Screen-printed Si solar cells were realized on 156x156 mm2 black Si substrates with resulting efficiencies...

Chandra Data Reveal Rapidly Whirling Black Holes

Science.gov (United States)

2008-01-01

A new study using results from NASA's Chandra X-ray Observatory provides one of the best pieces of evidence yet that many supermassive black holes are spinning extremely rapidly. The whirling of these giant black holes drives powerful jets that pump huge amounts of energy into their environment and affects galaxy growth. A team of scientists compared leading theories of jets produced by rotating supermassive black holes with Chandra data. A sampling of nine giant galaxies that exhibit large disturbances in their gaseous atmospheres showed that the central black holes in these galaxies must be spinning at near their maximum rates. People Who Read This Also Read... NASA’s Swift Satellite Catches First Supernova in The Act of Exploding Black Holes Have Simple Feeding Habits Jet Power and Black Hole Assortment Revealed in New Chandra Image Erratic Black Hole Regulates Itself "We think these monster black holes are spinning close to the limit set by Einstein's theory of relativity, which means that they can drag material around them at close to the speed of light," said Rodrigo Nemmen, a visiting graduate student at Penn State University, and lead author of a paper on the new results presented at American Astronomical Society in Austin, Texas. The research reinforces other, less direct methods previously used which have indicated that some stellar and supermassive black holes are spinning rapidly. According to Einstein's theory, a rapidly spinning black hole makes space itself rotate. This effect, coupled with gas spiraling toward the black hole, can produce a rotating, tightly wound vertical tower of magnetic field that flings a large fraction of the inflowing gas away from the vicinity of the black hole in an energetic, high-speed jet. Computer simulations by other authors have suggested that black holes may acquire their rapid spins when galaxies merge, and through the accretion of gas from their surroundings. "Extremely fast spin might be very common for large

Optical properties of sea ice doped with black carbon - an experimental and radiative-transfer modelling comparison

Science.gov (United States)

Marks, Amelia A.; Lamare, Maxim L.; King, Martin D.

2017-12-01

Radiative-transfer calculations of the light reflectivity and extinction coefficient in laboratory-generated sea ice doped with and without black carbon demonstrate that the radiative-transfer model TUV-snow can be used to predict the light reflectance and extinction coefficient as a function of wavelength. The sea ice is representative of first-year sea ice containing typical amounts of black carbon and other light-absorbing impurities. The experiments give confidence in the application of the model to predict albedo of other sea ice fabrics. Sea ices, ˜ 30 cm thick, were generated in the Royal Holloway Sea Ice Simulator ( ˜ 2000 L tanks) with scattering cross sections measured between 0.012 and 0.032 m2 kg-1 for four ices. Sea ices were generated with and without ˜ 5 cm upper layers containing particulate black carbon. Nadir reflectances between 0.60 and 0.78 were measured along with extinction coefficients of 0.1 to 0.03 cm-1 (e-folding depths of 10-30 cm) at a wavelength of 500 nm. Values were measured between light wavelengths of 350 and 650 nm. The sea ices generated in the Royal Holloway Sea Ice Simulator were found to be representative of natural sea ices. Particulate black carbon at mass ratios of ˜ 75, ˜ 150 and ˜ 300 ng g-1 in a 5 cm ice layer lowers the albedo to 97, 90 and 79 % of the reflectivity of an undoped clean sea ice (at a wavelength of 500 nm).

Exhumation of the Black Mountains in Death Valley, California, with new thermochronometric data from the Badwater Turtleback

Science.gov (United States)

Sizemore, T. M.; Cemen, I.; Wielicki, M. M.; Stockli, D. F.; Heizler, M. T.; Lutz, B. M.

2017-12-01

The Black Mountains, in Death Valley, California, are one of the key areas to better understand Basin and Range extension because they contain Cenozoic igneous and sedimentary rocks overlying mid- to deep-crustal, 1.74 Ga basement gneiss with abundant fault striations, large-scale extensional folds, and tectonite fabrics containing top-to-the-northwest shear-sense indicators. These rocks make up the footwall of three prominent, high-relief "turtleback" fault surfaces in the western flank of the Black Mountains, which are thought to have accommodated a significant amount of strain in the Death Valley area. It is unknown whether the missing Paleozoic and Mesozoic strata in the Black Mountains were removed in association with high-angle faulting, or along a continuous detachment surface with a rolling-hinge style of faulting as the hanging wall moved to the west, now forming the Panamint Range. The turtlebacks play an important role in resolving this question because they are commonly cited as containing conflicting evidence of both hypotheses. To provide insight into this problem, we are building an exhumation model across the Black Mountains using previously published thermochronometric data as well as new transect-based (U-Th)/He and Ar-Ar thermochronology and U-Pb geochronology for the Badwater turtleback. The model will provide a four-dimensional view of the exhumation history of the Black Mountains, to serve as evidence for either of the two previously mentioned hypotheses, or possibly some other style of exhumation. Additionally, we will compare the exhumation history of the Black Mountains to that of the Panamint Range using previously published data and interpretations. Our preliminary zircon U-Pb data suggest a crystallization age for the gneissic rocks on the Badwater turtleback of 1.74 Ga (207Pb/206Pb, 2σ error=31.8 Ma, n=6) with two younger populations at 1.46 Ga (207Pb/206Pb, 2σ error=51.8 Ma, n=3) and 79.6 Ma (206Pb/238U, 2σ error=10.0 Ma, n=2

Paranormal belief and attributional style.

Science.gov (United States)

Dudley, R T; Whisnand, E A

2000-06-01

52 college students completed Tobacyk's 1988 Revised Paranormal Belief Scale and Peterson, Semmel, von Baeyer, Abramson, Metalsky, and Seligman's 1982 Attributional Style Questionnaire. Analysis showed significantly higher depressive attributional styles among high scorers on paranormal phenomena than low scorers.

Visible light induced photoelectrochemical biosensing based on oxygen-sensitive quantum dots

Energy Technology Data Exchange (ETDEWEB)

Wang Wenjing; Bao Lei [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Lei Jianping, E-mail: jpl@nju.edu.cn [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Tu Wenwen [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Ju Huangxian, E-mail: hxju@nju.edu.cn [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China)

2012-09-26

Highlights: Black-Right-Pointing-Pointer The near-infrared QDs are synthesized in an aqueous solution. Black-Right-Pointing-Pointer QDs-based biosensor exhibits visible-light induced cathodic photocurrent. Black-Right-Pointing-Pointer The oxygen dependency of the photocurrent is verified. Black-Right-Pointing-Pointer A photoelectrochemical strategy is established by coupling with enzymatic reaction. Black-Right-Pointing-Pointer Photoelectrochemical sensor shows high upper detection limit, acceptable stability and accuracy. - Abstract: A visible light induced photoelectrochemical biosensing platform based on oxygen-sensitive near-infrared quantum dots (NIR QDs) was developed for detection of glucose. The NIR QDs were synthesized in an aqueous solution, and characterized with scanning electron microscopy and X-ray photoelectron spectroscopy. The as-prepared NIR QDs were employed to construct oxygen-sensitive photoelectrochemical biosensor on a fluorine-doped tin oxide (FTO) electrode. The oxygen dependency of the photocurrent was investigated at as-prepared electrode, which demonstrated the signal of photocurrent is suppressed with the decreasing of oxygen. Coupling with the consumption of oxygen during enzymatic reaction, a photoelectrochemical strategy was proposed for the detection of substrate. Using glucose oxidase (GOx) as a model enzyme, that is, GOx was covalently attached to the surface of CdTe QDs, the resulting biosensor showed the sensitive response to glucose. Under the irradiation of visible light of a wavelength at 505 nm, the proposed photoelectrochemical method could detect glucose ranging from 0.1 mM to 11 mM with a detection limit of 0.04 mM. The photoelectrochemical biosensor showed a good performance with high upper detection limit, acceptable stability and accuracy, providing an alternative method for monitoring biomolecules and extending the application of near-infrared QDs.

Leadership styles of hospital pharmacy directors.

Science.gov (United States)

Parrett, E E; Hurd, P D; Northcraft, G; McGhan, W F; Bootman, J L

1985-05-01

The leadership styles of hospital pharmacy directors and the association between leadership style, participative management, and innovative pharmaceutical services were studied using a mail questionnaire. The questionnaire was sent to 570 randomly selected hospital pharmacy directors. Included were a validated instrument that measures task-oriented versus relationship-oriented leadership behavior and other questions about participation of staff members, innovative services, and respondents' personal characteristics. The response rate was 69%. The majority of respondents perceived their leadership as highly relationship-oriented as well as highly task-oriented. Respondents with the "high relationship-high task" leadership style had the highest scores for subordinate participation. There were no significant differences in scores for innovative services by leadership style. A positive correlation between scores for subordinate participation and scores for innovative services was demonstrated. Most hospital pharmacy directors used a management style in which relationships and staff participation were important.

The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping

DEFF Research Database (Denmark)

Denney, Kelly D.; Bentz, Misty C.; Peterson, Bradley M.

2006-01-01

We present new observations leading to an improved black hole mass estimate for the Seyfert 1 galaxy NGC 4593 as part of a reverberation-mapping campaign conducted at the MDM Observatory. Cross-correlation analysis of the H_beta emission-line light curve with the optical continuum light curve...... reveals an emission-line time delay of 3.73 (+-0.75) days. By combining this time delay with the H_beta line width, we derive a central black hole mass of M_BH = 9.8(+-2.1)x10^6 M_sun, an improvement in precision of a factor of several over past results....

Active galaxies. A strong magnetic field in the jet base of a supermassive black hole.

Science.gov (United States)

Martí-Vidal, Ivan; Muller, Sébastien; Vlemmings, Wouter; Horellou, Cathy; Aalto, Susanne

2015-04-17

Active galactic nuclei (AGN) host some of the most energetic phenomena in the universe. AGN are thought to be powered by accretion of matter onto a rotating disk that surrounds a supermassive black hole. Jet streams can be boosted in energy near the event horizon of the black hole and then flow outward along the rotation axis of the disk. The mechanism that forms such a jet and guides it over scales from a few light-days up to millions of light-years remains uncertain, but magnetic fields are thought to play a critical role. Using the Atacama Large Millimeter/submillimeter Array (ALMA), we have detected a polarization signal (Faraday rotation) related to the strong magnetic field at the jet base of a distant AGN, PKS 1830-211. The amount of Faraday rotation (rotation measure) is proportional to the integral of the magnetic field strength along the line of sight times the density of electrons. The high rotation measures derived suggest magnetic fields of at least tens of Gauss (and possibly considerably higher) on scales of the order of light-days (0.01 parsec) from the black hole. Copyright © 2015, American Association for the Advancement of Science.

Gravitational lensing by spinning black holes in astrophysics, and in the movie Interstellar

International Nuclear Information System (INIS)

James, Oliver; Tunzelmann, Eugénie von; Franklin, Paul; Thorne, Kip S

2015-01-01

Interstellar is the first Hollywood movie to attempt depicting a black hole as it would actually be seen by somebody nearby. For this, our team at Double Negative Visual Effects, in collaboration with physicist Kip Thorne, developed a code called Double Negative Gravitational Renderer (DNGR) to solve the equations for ray-bundle (light-beam) propagation through the curved spacetime of a spinning (Kerr) black hole, and to render IMAX-quality, rapidly changing images. Our ray-bundle techniques were crucial for achieving IMAX-quality smoothness without flickering; and they differ from physicists’ image-generation techniques (which generally rely on individual light rays rather than ray bundles), and also differ from techniques previously used in the film industry’s CGI community. This paper has four purposes: (i) to describe DNGR for physicists and CGI practitioners, who may find interesting and useful some of our unconventional techniques. (ii) To present the equations we use, when the camera is in arbitrary motion at an arbitrary location near a Kerr black hole, for mapping light sources to camera images via elliptical ray bundles. (iii) To describe new insights, from DNGR, into gravitational lensing when the camera is near the spinning black hole, rather than far away as in almost all prior studies; we focus on the shapes, sizes and influence of caustics and critical curves, the creation and annihilation of stellar images, the pattern of multiple images, and the influence of almost-trapped light rays, and we find similar results to the more familiar case of a camera far from the hole. (iv) To describe how the images of the black hole Gargantua and its accretion disk, in the movie Interstellar, were generated with DNGR—including, especially, the influences of (a) colour changes due to doppler and gravitational frequency shifts, (b) intensity changes due to the frequency shifts, (c) simulated camera lens flare, and (d) decisions that the film makers made about

Gravitational lensing by spinning black holes in astrophysics, and in the movie Interstellar

Science.gov (United States)

James, Oliver; von Tunzelmann, Eugénie; Franklin, Paul; Thorne, Kip S.

2015-03-01

Interstellar is the first Hollywood movie to attempt depicting a black hole as it would actually be seen by somebody nearby. For this, our team at Double Negative Visual Effects, in collaboration with physicist Kip Thorne, developed a code called Double Negative Gravitational Renderer (DNGR) to solve the equations for ray-bundle (light-beam) propagation through the curved spacetime of a spinning (Kerr) black hole, and to render IMAX-quality, rapidly changing images. Our ray-bundle techniques were crucial for achieving IMAX-quality smoothness without flickering; and they differ from physicists’ image-generation techniques (which generally rely on individual light rays rather than ray bundles), and also differ from techniques previously used in the film industry’s CGI community. This paper has four purposes: (i) to describe DNGR for physicists and CGI practitioners, who may find interesting and useful some of our unconventional techniques. (ii) To present the equations we use, when the camera is in arbitrary motion at an arbitrary location near a Kerr black hole, for mapping light sources to camera images via elliptical ray bundles. (iii) To describe new insights, from DNGR, into gravitational lensing when the camera is near the spinning black hole, rather than far away as in almost all prior studies; we focus on the shapes, sizes and influence of caustics and critical curves, the creation and annihilation of stellar images, the pattern of multiple images, and the influence of almost-trapped light rays, and we find similar results to the more familiar case of a camera far from the hole. (iv) To describe how the images of the black hole Gargantua and its accretion disk, in the movie Interstellar, were generated with DNGR—including, especially, the influences of (a) colour changes due to doppler and gravitational frequency shifts, (b) intensity changes due to the frequency shifts, (c) simulated camera lens flare, and (d) decisions that the film makers made about

Applications of hidden symmetries to black hole physics

International Nuclear Information System (INIS)

Frolov, Valeri

2011-01-01

This work is a brief review of applications of hidden symmetries to black hole physics. Symmetry is one of the most important concepts of the science. In physics and mathematics the symmetry allows one to simplify a problem, and often to make it solvable. According to the Noether theorem symmetries are responsible for conservation laws. Besides evident (explicit) spacetime symmetries, responsible for conservation of energy, momentum, and angular momentum of a system, there also exist what is called hidden symmetries, which are connected with higher order in momentum integrals of motion. A remarkable fact is that black holes in four and higher dimensions always possess a set ('tower') of explicit and hidden symmetries which make the equations of motion of particles and light completely integrable. The paper gives a general review of the recently obtained results. The main focus is on understanding why at all black holes have something (symmetry) to hide.

Examining Determinants of Leadership Style Among Montenegrin Managers

Directory of Open Access Journals (Sweden)

Lojpur An൭elko

2015-03-01

Full Text Available As a leader's behavior can have a strong impact on different employee workrelated outcomes, various approaches have been put forth in an effort to determine the most effective form of leadership and determinants of individuals' choice of leadership style. This paper analyzed whether one's choice of leadership style is due more to personal or organizational characteristics. We used survey data to investigate the determinants of leadership style among Montenegrin managers. Our analysis showed that, although demographic characteristics such as gender, age, and education do not influence the choice of leadership style, internal organizational characteristics such as hierarchical level, managerial orientation to tasks/people, and decision-making characteristics such as decisionmaking style and decision-making environment are positively associated with the choice of democratic leadership style. This contributes to recent research in leadership that shows how some personal characteristics are considered to be less important in developing certain styles and that the choice of style is more dependent and contingent on external influences and situations.

Coping and metabolic syndrome indicators in urban black South African men: the SABPA study.

Science.gov (United States)

du Plessis, A; Malan, L; Malan, N T

2010-01-01

Urbanisation is associated with obesity, hypertension and development of the metabolic syndrome (MS). We aimed to assess the use of different coping styles and their influence on increases in MS indicators and target end-organ damage (TOD) in urban black African men. A sample of 53 men was classified as clear high active (AC, n = 30) or passive coping (PC, n = 23) responders, using the Amirkhan African validated coping style indicator. Blood pressure (BP) was recorded with an aneroid sphygmomanometer and waist circumference (WC) was determined. Carotid intima-media thickness (CIMT) and microalbuminuria were analysed to determine TOD. Fasting serum and eight-hour urine samples revealed elevated MS indicators in AC men. Strong associations existed between MS indicators and TOD in AC but not PC men. To conclude, only BP and seeking social support were positively associated with TOD in urban PC African men, while in urban AC African men, most MS indicators were positively associated with TOD, i.e. sub-clinical atherosclerosis and renal impairment.

Advanced infrared optically black baffle materials

International Nuclear Information System (INIS)

Seals, R.D.; Egert, C.M.; Allred, D.D.

1990-01-01

Infrared optically black baffle surfaces are an essential component of many advanced optical systems. All internal surfaces in advanced infrared optical sensors that require stray light management to achieve resolution are of primary concern in baffle design. Current industrial materials need improvements to meet advanced optical sensor systems requirements for optical, survivability, and endurability. Baffles are required to survive and operate in potentially severe environments. Robust diffuse-absorptive black surfaces, which are thermally and mechanically stable to threats of x-ray, launch, and in-flight maneuver conditions, with specific densities to allow an acceptable weight load, handleable during assembly, cleanable, and adaptive to affordable manufacturing, are required as optical baffle materials. In this paper an overview of recently developed advanced infrared optical baffle materials, requirements, manufacturing strategies, and the Optics MODIL (Manufacturing Operations Development and Integration Laboratory) Advanced Baffle Program are discussed

Humor styles moderate borderline personality traits and suicide ideation.

Science.gov (United States)

Meyer, Neil A; Helle, Ashley C; Tucker, Raymond P; Lengel, Gregory J; DeShong, Hilary L; Wingate, LaRicka R; Mullins-Sweatt, Stephanie N

2017-03-01

The way individuals use humor to interact interpersonally has been associated with general personality, depression, and suicidality. Certain humor styles may moderate the risk for suicide ideation (SI) in individuals who are high in specific risk factors (e.g., thwarted belongingness, perceived burdensomeness). Previous research suggests a relationship between humor styles and borderline personality disorder (BPD) and an increased risk of suicidality and suicide completion in individuals with BPD. Participants (n =176) completed measures of BPD traits, SI, and humor styles. It was hypothesized that BPD traits would be positively correlated with negative humor styles and negatively correlated with positive humor styles, and that humor styles would significantly moderate BPD traits and SI. Results showed that BPD traits were negatively correlated with self-enhancing humor styles and positively correlated with self-defeating humor styles, but that they were not significantly correlated with affiliative or aggressive humor styles. Bootstrapping analyses demonstrated that the affiliative, self-enhancing, and self-defeating humor styles significantly moderated BPD traits and SI, while the aggressive humor style did not. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Evaluación de técnicas de aplicación de Steinernema carpocapsae

Directory of Open Access Journals (Sweden)

Ayala Luz Dary

2004-12-01

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style="text-align: justify;">style="font-size: small;">style="color: black; font-family: ";Baskerville";,";serif";;">El barrenador gigante de la palma recientemente ha adquirido importancia económica en los Llanos Orientales colombianos. Para su control se utiliza el nematodo entomoparásito S. style="color: black; font-family: ";Baskerville-Italic";,";serif";;">carpocapsaestyle="font-size: small; font-family: Baskerville;">style="font-family: Times New Roman;">style="font-size: small; font-family: Baskerville;">, usando una regadera de jardín. Este método se considera eficaz, pero el tiempo para la liberación en campo es considerable, elevando los costos de aplicación. Consecuentemente, se evaluaron cuatro técnicas de aplicación usando los equipos Jacto Súper 600®, Maruyama MS256®, Royal Cóndor® y la regadera de jardín, para establecer la mortalidad de style="font-size: small; font-family: Baskerville;">style="color: black; font-family: ";Baskerville-Italic";,";serif";;">S. carpocapsae style="font-size: small; font-family: Baskerville;">style="font-size: small;">style="font-size: small; font-family: Baskerville;">en diferentes partes de estos equipos: tanque de mezcla (TM, salida de bomba (SB, antes de boquilla (AB y después de ésta, y a la salida del equipo (SE. Se utilizó un diseño de parcelas divididas (parcela principal: equipos; subparcelas: sitios de muestreo. La menor mortalidad del nematodo ocurrió con la regadera (19%, seguida de las encontradas con los equipos Maruyama® (44% y Royal Cóndor® (58%. Por su parte, con el equipo Jacto® se produjo el mayor daño (68%. No obstante, las mayores variaciones al comparar la cantidad de style="font-size: small; font-family: Baskerville;">style="color: black; font-family: ";Baskerville-Italic";,";serif";;">S. carpocapsae