cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Luminous Compact Blue Galaxies up to z~1 in the HST Ultra Deep Field: I. Small galaxies, or blue centers of massive disks?
Creators: name: Noeske, K. G.
name: Koo, D. C.
name: Phillips, A. C.
name: Willmer, C. N. A.
name: Melbourne, J.
name: de Paz, A. Gil
name: Papaderos, P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We analyze 26 Luminous Compact Blue Galaxies (LCBGs) in the HST/ACS Ultra Deep Field (UDF) at z ~ 0.2-1.3, to determine whether these are truly small galaxies, or rather bright central starbursts within existing or forming large disk galaxies. Surface brightness profiles from UDF images reach fainter than rest-frame 26.5 B mag/arcsec^2 even for compact objects at z~1. Most LCBGs show a smaller, brighter component that is likely star-forming, and an extended, roughly exponential component with colors suggesting stellar ages >~ 100 Myr to few Gyr. Scale lengths of the extended components are mostly >~ 2 kpc, >1.5-2 times smaller than those of nearby large disk galaxies like the Milky Way. Larger, very low surface brightness disks can be excluded down to faint rest-frame surface brightnesses (>~ 26 B mag/arcsec^2). However, 1 or 2 of the LCBGs are large, disk-like galaxies that meet LCBG selection criteria due to a bright central nucleus, possibly a forming bulge. These results indicate that >~ 90% of high-z LCBGs are small galaxies that will evolve into small disk galaxies, and low mass spheroidal or irregular galaxies in the local Universe, assuming passive evolution and no significant disk growth. The data do not reveal signs of disk formation around small, HII-galaxy-like LCBGs, and do not suggest a simple inside-out growth scenario for larger LCBGs with a disk-like morphology. Irregular blue emission in distant LCBGs is relatively extended, suggesting that nebular emission lines from star-forming regions sample a major fraction of an LCBG's velocity field.
description: 11 pages, 2 figures, AASTeX; accepted for publication in Astrophysical Journal Letters
Generalised velocity-dependent one-scale model for current-carrying strings
Creators: name: Martins, C. J. A. P.
name: Peter, Patrick
name: Rybak, I. Yu.
name: Shellard, E. P. S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We develop an analytic model to quantitatively describe the evolution of superconducting cosmic string networks. Specifically, we extend the velocity-dependent one-scale (VOS) model to incorporate arbitrary currents and charges on cosmic string worldsheets under two main assumptions, the validity of which we also discuss. We derive equations that describe the string network evolution in terms of four macroscopic parameters: the mean string separation (or alternatively the string correlation length) and the root mean square (RMS) velocity which are the cornerstones of the VOS model, together with parameters describing the averaged timelike and spacelike current contributions. We show that our extended description reproduces the particular cases of wiggly and chiral cosmic strings, previously studied in the literature. This VOS model enables investigation of the evolution and possible observational signatures of superconducting cosmic string networks for more general equations of state, and these opportunities will be exploited in a companion paper.
description: 17 pages, 6 figures
Heat transfer in strained twin graphene: A non-equilibrium molecular dynamics simulation
Creators: name: Rezaee, Fatemeh
name: Yousefi, Farrokh
name: Khoeini, Farhad
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In this work, we study the thermal energy transport properties of twin graphene, which has been introduced recently as a new two-dimensional carbon nano structure. The thermal conductivity is investigated using non-equilibrium molecular dynamics simulation. We examine the effects of the length, temperature, and also the uni axial strain along with both armchair and zigzag directions. We found that the conductivity increases with growing the system length, while that slightly decreases with increasing the mean temperature of the system. Moreover, it is shown that the applied strain up to 0.02 will increase the thermal conductivity, and in the interval 0.02-0.06, it has a decreasing trend which can be used for tuning the thermal properties. Finally, the phonon density of states is investigated to study the behavior of thermal conductivity, fundamentally. We can control the thermal properties of the system with changing parameters such as strain. Our results may be important in the design of cooling electronic devices and thermal circuits.
description: 15 pages, 6 figures
Local electronic structure of dilute hydrogen in $β$-MnO$_{2}$
Creators: name: Okabe, H.
name: Hiraishi, M.
name: Koda, A.
name: Takeshita, S.
name: Kojima, K. M.
name: Yamauchi, I.
name: Ohsawa, T.
name: Ohashi, N.
name: Sato, H.
name: Kadono, R.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electronic and magnetic states of $β$-MnO$_{2}$ in terms of hydrogen impurities have been investigated by muon spin rotation ($μ$SR) technique combined with density-functional theory (DFT) calculations for muon as pseudo-hydrogen. We found that 85% of implanted muons are localized in the oxygen channels of the rutile structure and behave as interstitial protons (Mu$^{+})$ except those (7.6%) forming a charge-neutral state (Mu$^{0})$ at 2.3 K, which indicates that interstitial hydrogen acts as a shallow donor within less than 0.1 meV of ionization energy. The residual 15% of muons are attributed to those related to lattice imperfection as Mn vacancies. Detailed analyses combined with DFT approach suggested that the muon is localized at the center of the oxygen channel due to its large zero-point vibration energy.
description: 8 pages, 8 figures
Experimental hint for gravitational CP violation
Creators: name: Gharibyan, V.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: An equality of particle and antiparticle gravitational interactions holds in general relativity and is supported by indirect observations. Gravity dependence on rotation or spin direction is experimentally constrained for non-relativistic matter. Here a method based on high energy Compton scattering is developed to measure the gravitational interaction of accelerated charged particles. Within that formalism the Compton spectra measured at HERA rule out the speculated anti-gravity possibility for antimatter at a confidence level close to 100%. The same data, however, imply a gravitational CP violation around 13 GeV energies, by a maximal amount of 9 +/- 2 ppt for the charge and 13 +/- 3 ppt for the space parity. The detected asymmetry hints for a stronger gravitational coupling to left helicity electrons relative to right helicity positrons.
description: 13 pages, 4 figures. Extends my results (C-parity) described in arXiv:1507.02589: P-parity is added since the positron spectrum on Fig.3 was obtained with left helicity laser light
Energetics and dynamics of an impulsive flare on March 10, 2001
Creators: name: Chandra, Ramesh
name: Jain, Rajmal
name: Uddin, Wahab
name: Yoshimura, Keiji
name: Kosugi, T.
name: Sakao, T.
name: Joshi, Anita
name: Despandey, M. R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the H$α$ observations from ARIES, Nainital of a compact and impulsive solar flare occurred on March 10, 2001 and associated with a CME. We have also analysed HXT, SXT/Yohkoh observations as well as radio observations from Nobeyama Radio Observatory to derive the energetics and dynamics of this impulsive flare. We co-align the H$α$, SXR, HXR, MW and magnetogram images within the instrumental spatial resolution limit. We detect a single HXR source in this flare, which is found spatially associated with one of the H$α$ bright kernel. The unusual feature of HXR and H$α$ sources, observed for the first time, is the rotation during the impulsive phase in clockwise direction. We propose that the rotation may be due to asymmetric progress of the magnetic reconnection site or may be due to the change of peak point of the electric field. In MW emission we found two sources, one is main source which is at the main flare site and another is remote source located in South-West direction. It appears that the remote source is formed by the impact of accelerated energetic electrons from the main flare site. From the spatial co-relation of multi-wavelength images of th
description: Accepted in Solar Physics, 20 pages, 12 Figures
Cosmic shear power spectra in practice
Creators: name: Nicola, Andrina
name: García-García, Carlos
name: Alonso, David
name: Dunkley, Jo
name: Ferreira, Pedro G.
name: Slosar, Anže
name: Spergel, David N.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Cosmic shear is one of the most powerful probes of Dark Energy, targeted by several current and future galaxy surveys. Lensing shear, however, is only sampled at the positions of galaxies with measured shapes in the catalog, making its associated sky window function one of the most complicated amongst all projected cosmological probes of inhomogeneities, as well as giving rise to inhomogeneous noise. Partly for this reason, cosmic shear analyses have been mostly carried out in real-space, making use of correlation functions, as opposed to Fourier-space power spectra. Since the use of power spectra can yield complementary information and has numerical advantages over real-space pipelines, it is important to develop a complete formalism describing the standard unbiased power spectrum estimators as well as their associated uncertainties. Building on previous work, this paper contains a study of the main complications associated with estimating and interpreting shear power spectra, and presents fast and accurate methods to estimate two key quantities needed for their practical usage: the noise bias and the Gaussian covariance matrix, fully accounting for survey geometry, with some of these results also applicable to other cosmological probes. We demonstrate the performance of these methods by applying them to the latest public data releases of the Hyper Suprime-Cam and the Dark Energy Survey collaborations, quantifying the presence of systematics in our measurements and the validity of the covariance matrix estimate. We make the resulting power spectra, covariance matrices, null tests and all associated data necessary for a full cosmological analysis publicly available.
description: 42 pages, 16 figures, 4 tables, to be submitted to JCAP
Creation of a novel inverted charge density wave state
Creators: name: Zhang, Yingchao
name: Shi, Xun
name: Guan, Mengxue
name: You, Wenjing
name: Zhong, Yigui
name: Kafle, Tika R.
name: Huang, Yaobo
name: Ding, Hong
name: Bauer, Michael
name: Rossnagel, Kai
name: Meng, Sheng
name: Kapteyn, Henry C.
name: Murnane, Margaret M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Charge density wave (CDW) order is an emergent quantum phase that is characterized by a periodic lattice distortion and charge density modulation, often present near superconducting transitions. Here we uncover a novel inverted CDW state by using a femtosecond laser to coherently over-drive the unique star-of-David lattice distortion in 1T-TaSe$_2$. We track the signature of this novel CDW state using time- and angle-resolved photoemission spectroscopy and time-dependent density functional theory, and validate that it is associated with a unique lattice and charge arrangement never before realized. The dynamic electronic structure further reveals its novel properties, that are characterized by an increased density of states near the Fermi level, high metallicity, and altered electron-phonon couplings. Our results demonstrate how ultrafast lasers can be used to create unique states in materials, by manipulating charge-lattice orders and couplings.
description: 13 pages, 5 figures
Understanding local wind circulations over White Sands Missile Range
Creators: name: Silva, Armand
name: Warner, Thomas
name: Hahmann, Andrea
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2006
Subjects: Wind-field climatology
Wind patterms
Mesoscale
Temperature
Wind roses
Topographic effects
Diurnal cycle

This study builds a local wind-field climatology and analyzes the resulting wind patterns at White Sands Missile Range (WSMR) in southern New Mexico. Mesoscale circulations in mountain-valley desert regions have been previously studied in several regions of the Intermountain West, none of which included WSMR. Hourly surface mesonet (SAMS) data were collected at 13 stations across WSMR over five years from 2001 through 2005. The months and hours of approximate minimum and maximum temperature, along with a few intermediate times, were selected to analyze local mesoscale wind behaviors. These data were visualized in the form of wind roses, which plot wind speed, direction and frequency. Wind roses were plotted on a terrain map at the data locations for the analysis of topographic effects on wind circulations. This analysis shows that mesoscale patterns of upslope and downslope flows, as well as up-valley and down-valley flows occur, depending on the season of the year and hour within the diurnal cycle. Additionally, the analysis shows that significant variations occur across the different stations, depending on their locations on the valley floor or mountain slopes. The results of this study enhance the understanding of local wind patterns in desert valley regions in general. This has great importance because of todayâs rapid growth of human population in these regions.
Surface Generation Analysis in Micro End-Milling Considering the Influences of Grain
Creators: name: Wang, J.
name: Gong, Y.
name: Abba, G.
name: Chen, Kui
name: Shi, J.
name: Cai, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Computer Science (cs.OH)
subject: FOS: Computer and information sciences

description: Micro end-milling method is a universal micro manufacturing method, which can be used to fabricating complex 3D structures and parts with many materials. But compared with their micrometer order size, their surface roughness quality is not satisfied. In this paper, the different metal phase grains influences are researched, and the micro end-milling process is described while the material is anisotropic. In this paper, the physical characteristics of different grains, especially friction coefficient and elastic module, are very critical to determine the chip formation process and surface generation. The chip is often discontinues because of the grain boundary effect. Through the micro end-milling experiment, the bottom surface results correlate very well with the theory analysis.
description: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing)
Global Solutions to the initial boundary problem of 3-D compressible Navier-Stokes-Poisson on bounded domains
Creators: name: Liu, Hairong
name: Zhong, Hua
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: The initial boundary value problems for compressible Navier-Stokes-Poisson is considered on a bounded domain in $\mathbb{R}^3$ in this paper. The global existence of smooth solutions near a given steady state for compressible Navier-Stokes-Poisson with physical boundary conditions is established with the exponential stability. An important feature is that the steady state (except velocity) and the background profile are allowed to be of large variation.
description: 31pages
The galaxy "missing dark matter" NGC1052-DF4 is undergoing tidal disruption
Creators: name: Montes, Mireia
name: Infante-Sainz, Raúl
name: Madrigal-Aguado, Alberto
name: Román, Javier
name: Monelli, Matteo
name: Borlaff, Alejandro S.
name: Trujillo, Ignacio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The existence of long-lived galaxies lacking dark matter represents a challenge to our understanding of how galaxies form. Here, we present evidence that explains the lack of dark matter in one of such galaxies: NGC1052-DF4. Deep optical imaging of the system has detected tidal tails in this object caused by its interaction with its neighbouring galaxy NGC1035. As stars are more centrally concentrated than the dark matter, the tidal stripping will remove a significant percentage of the dark matter before affecting the stars of the galaxy. Only ~7% of the stellar mass of the galaxy is in the tidal tails, suggesting that the stars of NGC1052-DF4 are starting only now to be affected by the interaction, while the percentage of remaining dark matter is <1%. This naturally explains the low content of dark matter inferred for this galaxy and reconciles these type of galaxies with our current models of galaxy formation.
description: 18 pages, 9 figures, accepted for publication in ApJ; The main results of the paper are shown in figures 5 and 8
Matter shear and vorticity in conformally flat spacetimes
Creators: name: Mayala, Roger
name: Goswami, Rituparno
name: Maharaj, Sunil D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper we consider conformally flat perturbations on the Friedmann Lemaitre Robertson Walker (FLRW) spacetime containing a general matter field. Working with the linearised field equations, we unearth some important geometrical properties of matter shear and vorticity and how they interact with the thermodynamical quantities in the absence of any free gravity powered by the Weyl curvature. As there are hardly any physically realistic rotating exact conformally flat solutions in general relativity, these covariant and gauge invariant results bring out transparently the role of vorticity in the linearised regime. Most interestingly, we demonstrate that the matter shear obeys a transverse traceless tensor wave equation, and the vorticity obeys a vector wave equation in this regime. These shear and vorticity waves replace the gravitational waves in the sense that they causally carry the information about local change in the curvature of these spacetimes.
description: 7 pages, Revtex4
Flavoured Warped Axion
Creators: name: Bonnefoy, Quentin
name: Cox, Peter
name: Dudas, Emilian
name: Gherghetta, Tony
name: Nguyen, Minh D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a 5D extension of the DFSZ axion model that addresses both the axion quality and fermion mass hierarchy problems, and predicts flavour-dependent, off-diagonal axion-fermion couplings. The axion is part of a 5D complex scalar field charged under a U(1)$_{PQ}$ symmetry that is spontaneously broken in the bulk, and is insensitive to explicit PQ breaking on the UV boundary. Bulk Standard Model fermions interact with two Higgs doublets that can be localized on the UV boundary or propagate in the bulk to explain the fermion masses and mixings. When the Higgs doublets are localized on the UV boundary, they induce flavour diagonal couplings between the fermions and the axion. However, when the Higgs doublets propagate in the bulk, the overlap of the axion and fermion profiles generates flavour off-diagonal couplings. The effective scale of these off-diagonal couplings in both the quark and lepton sectors can be as small as $10^{11}$ GeV, and therefore will be probed in future precision flavour experiments.
description: 40 pages, 13 figures
Absolute V-band magnitudes and mass-to-light ratios of Galactic globular clusters
Creators: name: Baumgardt, H.
name: Sollima, A.
name: Hilker, M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have used HST and ground-based photometry to determine total $V$-band magnitudes and mass-to-light ratios of more than 150 Galactic globular clusters. We do this by summing up the magnitudes of their individual member stars, using color-magnitude information, Gaia DR2 proper motions and radial velocities to distinguish cluster stars from background stars. Our new magnitudes confirm literature estimates for bright clusters with V<8, but can deviate by up to two magnitudes from literature values for fainter clusters. They lead to absolute mass-to-light ratios that are confined to the narrow range 1.4
description: 19 pages, 8 figures, accepted for publication in PASA
Abrupt Transitions in Variational Quantum Circuit Training
Creators: name: Campos, Ernesto
name: Nasrallah, Aly
name: Biamonte, Jacob
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Variational quantum algorithms dominate gate-based applications of modern quantum processors. The so called, {\it layer-wise trainability conjecture} appears in various works throughout the variational quantum computing literature. The conjecture asserts that a quantum circuit can be trained piece-wise, e.g.~that a few layers can be trained in sequence to minimize an objective function. Here we prove this conjecture false. Counterexamples are found by considering objective functions that are exponentially close (in the number of qubits) to the identity matrix. In the finite setting, we found abrupt transitions in the ability of quantum circuits to be trained to minimize these objective functions. Specifically, we found that below a critical (target gate dependent) threshold, circuit training terminates close to the identity and remains near to the identity for subsequently added blocks trained piece-wise. A critical layer depth will abruptly train arbitrarily close to the target, thereby minimizing the objective function. These findings shed new light on the divide-and-conquer trainability of variational quantum circuits and apply to a wide collection of contemporary literature.
description: 11 pages, 8 figures, RevTeX
Effect of the Gulf of Mexico's mixed layer depth on hurricane intensity in the warming environment
Creators: name: Trent, Kimberly
name: Washington, Warren
name: Randall, David
name: Gettelman, Andrew
name: Lampert, Annette
name: Rivera Rivera, Nancy
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2006
Subjects: Ocean depth
Global warming
Hurricane Katrina
Sea surface temperatures
Warm core rings
Peak intensity
Forecasting

Due to the effect of mixed layer ocean depth in the Gulf of Mexico on hurricane intensity, it is important to understand how global warming will affect the ocean and how this in turn will affect hurricane intensity. We ran the ARW model for Hurricane Katrina with the Gulf of Mexicoâs mixed layer depth distribution specified, and we compared the results to actual events to determine the accuracy of the model for its use in future predictions; then we reran the model adjusted for projected sea surface temperatures (SSTs) for the year 2100 due to global warming. The analysis showed that, due to the higher water temperature, the intensity of the hurricane started to increase more quickly in the beginning of the run which altered its track, causing it to cross over a deeper part of the mixed layerâs warm core rings (WCRs) which helped it to maintain its peak intensity for a longer period of time than in the present day simulation. This preliminary analysis demonstrates the importance of including the depth of the mixed layer when forecasting and simulating hurricanes, and implies that global warming may increase the intensity of hurricanes in the Gulf of Mexico.
Analyzing ozone formation sensitivities in the Mexico City Metropolitan Area
Creators: name: Wang, Julien
name: Tie, Xue
name: Madronich, Sasha
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2006
Subjects: Tropospheric ozone
Pollutant
Limiting reactant
Bivariate correlations
Volatile organic compounds

One major pollutant of concern is in the Mexico City Metropolitan Area (MCMA) is tropospheric ozone. It is a secondary pollutant that damages local vegetation and the human respiratory system. Ozone is formed in the atmosphere by nitrogen oxides (NOx) and volatile organic compounds (VOCs), but it is unclear which of these two is the limiting reactant. Finding the limiting reactant would allow legislators to take proper measures to control ozone concentrations. The weekend effects of ozone, NOx, and CO (an indicator for VOC) were analyzed from 1986-2003. It was found that though there was a definite normal weekend effect for NOx and CO, there was no consistent weekend effect for ozone. This made it difficult to pinpoint the limiting reactant of ozone formation. The CO/NOx ratio was then calculated to study possible correlations with ozone concentration. There was a positive and almost linear relationship between ozone concentration and the CO/NOx ratio. This means that as CO (VOC) increased, ozone concentrations increased as well. Next, bivariate correlations were performed and they gave a good and positive relationship for CO/NOx ratio and ozone concentrations. However, there was no clear relationship between ozone concentration and PM10, and ozone and SOâ. Finally, the calculated ozone sensitivity coefficient showed that in the MCMA, ozone concentrations were usually VOC sensitive. This clarifies the limiting reactant of ozone formation and shows that limiting VOCs would cut down on tropospheric ozone concentrations.
Using CCSM3 to simulate climate changes caused by the 8.2ka meltwater pulse
Creators: name: Burt, Melissa
name: Morrill, Carrie
name: Wiedinmyer, Christine
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2005

During abrupt climate changes, the climate system is forced across some threshold, causing evolution to a new, persistent state. Studies of abrupt climate changes are necessary to understand how these changes are transferred globally and to gain insight on future climate change. In this research, we simulated an abrupt climate change at 8.2ka (8200 years ago) using the Community Climate System Model (CCSM) and focusing specifically on the global response of temperature and precipitation. This abrupt change was believed to have been caused by a massive amount of freshwater entering the Labrador Sea from a glacial lake near Hudson Bay. Previous simulations of this event used climate models of intermediate complexity or present-day boundary conditions for greenhouse gases and insolation. In this research, we used boundary conditions from 8.2 ka and a more comprehensive coupled climate model to improve the accuracy of the simulation. We found significant global changes, annually and seasonally, in temperature and precipitation. The average annual global temperature before the freshwater perturbation was 12.1 °C and after the hosing was 10.7 °C, corresponding to a −1.3 °C change. Globally, the annual precipitation change was −0.08 mm day⁻¹. T-tests indicate that these changes, globally and regionally, were statistically significant at the 95% confidence level. These changes occurred in part due to a slowdown of the Atlantic meridional overturning (thermohaline) circulation and the resulting increase in the amount of sea ice in the North Atlantic. This, in turn, increased the Earth's albedo and the Earth absorbed less incoming solar radiation.
Quantifying the effects of different clear-cut sizes on ectomycorrhizal fungi at a subalpine forest : persistence and diversity
Creators: name: Hagerman, Shannon Marie
Publisher: name: University of British Columbia
Year: 2009

description: The overall objective of this thesis was to assess the influence of different clear-cut sizes on the survival of ectomycorrhizal fungi one and two growing seasons after logging. A comparative study involving a greenhouse bioassay and a survey of ectomycorrhizal roots from soil cores detected very different assemblages of the ectomycorrhizal fungal community one growing season after host removal. These differences are thought to be the result of variation in fungal activity and differences in epidemiology. Two growing seasons after host removal, a survey of ectomycorrhizal roots from soil cores revealed that both the numbers of active ectomycorrhizae and the diversity of ectomycorrhizae were significantly reduced at clear-cut plots relative to the undisturbed forest. Specifically, there was a significant decrease in diversity with increasing distance from the block edge. There were no differences in diversity at the same distance from the edge of different sized clear-cuts. A field bioassay showed that the diversity of ectomycorrhizal fungi capable of colonizing young spruce seedlings two growing seasons after host removal was significantly reduced with distance from the block edge. The critical distance beyond which diversity decreased was 16 - 25m. As with the results of the survey of ectomycorrhizae from soil cores, there were no differences in diversity at the same distance from the edge of different sized clear-cuts. These results suggest that, in clear-cuts ranging in size from 0.1 to 10 ha, distance from the edge, or proximity to overstory trees, is more important to patterns of ectomycorrhizal persistence and diversity than opening size. The use of vital stains revealed that fungal tissue associated with 'active' mycorrhizae is viable yet not metabolically active.
Synoptic analysis of 2000-2005 significant snowfall events on Mt. Kilimanjaro
Creators: name: Chan, Rebecca
name: Ammann, Caspar
name: Yin, Jeffrey
name: Petruzzi, Barbara
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2005
Subjects: Tropical precipitation bands

Ice cores recovered from Mt. Kilimanjaro provide evidence of significant climate changes in the East African region over the past 10,000 years. However, the atmospheric processes that lead to snowfall on Kilimanjaro are poorly understood. Earlier studies have suggested that East African climate is dominated by the seasonal shift of the tropical precipitation bands, yet the key factors causing interannual precipitation variability remain unclear, particularly for the long rains season (March-May). To advance the understanding of modern East African climate, this study used data from a new station on top of Mt. Kilimanjaro and put them into a regional atmospheric circulation context. First, the in situ data were compared to global analysis products for testing their representation of the East African region. Overall, these data showed similar activity during corresponding days of snowfall on Kilimanjaro, indicating that snowfall events are likely related to regional precipitation. Second, the use of various global (re-)analysis products allowed the examination of commonalities between individual precipitation events on Kilimanjaro, and helped to identify the key precipitation-causing processes. Results showed distinct seasonality in precipitation, propagating from west to east during the long rains and east to west during the short rains (October-December). In addition, high magnitude snowfall events occurred under the conditions of low wind speed and high humidity. Therefore, high magnitude events may be a result of local convection, and these events may represent certain atmospheric conditions favorable for snowfall accumulation, but their representation of overall regional rainfall totals remains uncertain.
The Effect of One-on-One Student Mentoring on the Negative Behavior of Middle School Students
Creators: name: Aue, Bryan
Publisher: name: Maryland Shared Open Access Repository
Year: 2014
Subjects: subject: Negative Behavior, Middle School, Positive Behavior, Student Mentoring, Check-In, Check-Out, Discipline, Interventions, PBIS
subject: Education -- Research papers (Graduate)

description: The purpose of this study was to determine if the number of referrals a middle school student receives would change following a one-on-one student mentoring intervention (Check-In/Check-Out). The measurement tool was the number of minor and major discipline referrals as recorded by STARS. This study involved use of a pre-experimental design where one group of students received the intervention and data was examined before and after the intervention. Reductions in the number of minor referrals were significant for the students participating in the study. There was no significant change in the number of major referrals following the intervention. Research in this area should continue as school boards are looking for alternatives to suspension and the study showed signs of affecting behavior in a positive way.
An Integrated Circuit Compatible Compact Package for Thermal Gas Flowmeters
Creators: name: Bruschi, P.
name: Nurra, V.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Computer Science (cs.OH)
subject: FOS: Computer and information sciences

description: An original packaging method suitable for integrated thermal mass flow sensors is presented. The method consists in the application of a plastic transparent adapter to the chip surface. The adapter is sealed to the chip surface by means of a thermal procedure. By this approach it is possible to selectively convey the fluid flow to reduced chip areas, avoiding contact with the pads. Fabrication and testing of a very compact flow sensor is described.
description: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing)
Stratosphere-Troposhere Exchange via cross-tropopause mixing in the extratropics
Creators: name: Diaz, Karen
name: Weinheimer, Andrew
name: Rew, Juliana
name: Evans, Janet
name: Burt, Melissa
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2005
Subjects: Chemical composition
Oxidation reactions
Aircraft measurements

Stratosphere-Troposphere Exchange (STE) is the bi-directional exchange or transfer of mass and chemical species between the stratosphere and troposphere. STE helps determine the chemical composition of the stratosphere and troposphere, and thus affects climate, stratospheric ozone, and oxidation reactions in the troposphere. However, the ways it occurs are poorly understood. STE is expected across the tropopause, located between the troposphere and stratosphere. Data from three observational projects were studied for evidence of mixing: SUCCESS, TRACE-P, and CRYSTAL-FACE. Aircraft measurements were used to make correlation graphs of ozone versus carbon monoxide concentrations. Mixing, evident in high carbon monoxide (CO) concentrations in the lower stratosphere, was found for all projects. TRACE-P measurements showed relatively lower CO concentrations in the lower stratosphere, in spite of the high CO concentrations seen in the upper troposphere due to pollution episodes. CRYSTAL-FACE showed the highest CO concentration deep into the stratosphere on July 7 and 9, 2002. During these days, plumes from surface fires reached high into the stratosphere. High CO concentrations were recorded on July 3 for CRYSTAL-FACE and May 2 for SUCCESS, although they were not as deep into the stratosphere. Back trajectories possibly show fire plumes that reached the lower stratosphere on July 3. Back trajectories could possibly show a Warm Conveyor Belt on the Eastern Central Pacific that could have lifted polluted air from Asia to the vicinity of the tropopause on May 2.
Further constraints on electron acceleration in solar noise storms
Creators: name: Subramanian, Prasad
name: Becker, Peter A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We reexamine the energetics of nonthermal electron acceleration in solar noise storms. A new result is obtained for the minimum nonthermal electron number density required to produce a Langmuir wave population of sufficient intensity to power the noise storm emission. We combine this constraint with the stochastic electron acceleration formalism developed by Subramanian & Becker (2005) to derive a rigorous estimate for the efficiency of the overall noise storm emission process, beginning with nonthermal electron acceleration and culminating in the observed radiation. We also calculate separate efficiencies for the electron acceleration -- Langmuir wave generation stage and the Langmuir wave -- noise storm production stage. In addition, we obtain a new theoretical estimate for the energy density of the Langmuir waves in noise storm continuum sources.
description: Accepted for publication in Solar Physics
Using GPS radio occultation data in the study of tropical cyclogenesis
Creators: name: Didlake, Anthony
name: Kuo, Ying-Hwa
name: Metcalfe, Travis
Publisher: name: University Corporation For Atmospheric Research (UCAR)
Year: 2005
Subjects: Typhoon season
Wind fields
Data assimilation

Numerous studies have examined atmospheric conditions and patterns in tropical cyclogenesis. Although much has been accomplished, a complete understanding of tropical cyclogenesis is hindered by the lack of data in the regions where formation occurs. The GPS (Global Positioning System) radio occultation technique can provide valuable data in key areas. In GPS radio occultation, GPS satellites emit radio signals through the atmosphere that are received by another satellite in a low Earth orbit. Various atmospheric properties are calculated based on the alteration of the signal. This study assessed the value of GPS radio occultation data in the study of tropical cyclogenesis by examining storms of the 2002 Western North Pacific typhoon season. The signature of precursor disturbances to tropical cyclogenesis was determined by analyzing composites of data from the NCEP Aviation (AVN) analysis over four days. Similar composites of GPS radio occultation data were produced. The AVN analysis showed strong signals of precursor disturbances in the low-level wind fields and atmospheric refractivity. The GPS radio occultation data detected similarly increased refractivity values in corresponding regions, but had sizeable measurement differences with the AVN analysis. These differences were attributed to AVN analysis error due to the lack of input observational data and the high accuracy of GPS radio occultation measurements. Further comparisons showed that with the limited quantity of data currently available, GPS radio occultation by itself was not sufficient to detect precursor disturbances. It can best be used in data assimilation to improve the analysis and forecasts of tropical storms.
A High Power Density Electrostatic Vibration-to-Electric Energy Converter Based On An In-Plane Overlap Plate (IPOP) Mechanism
Creators: name: Paracha, A. M.
name: Basset, Ph.
name: Marty, F.
name: Chasin, A. Vaisman
name: Poulichet, P.
name: Bourouina, T.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Computer Science (cs.OH)
subject: FOS: Computer and information sciences

description: In this paper, design, fabrication and characterization issues of a bulk silicon-based, vibration powered, electric energy generator are addressed. The converter is based on an In-Plane Overlap Plate (IPOP) configuration [1]. Measurements have shown that with a theoretically lossless electronics and a starting voltage of 5 V, power density of 58 $μ$W/cm3 is achievable at the resonance frequency of 290 Hz. It can be further improved by reducing the parasitic capacitance, which can be achieved by silicon etching, but a considerable mass is lost. In [2], it is shown that 19% of mass reduction improves power density from 12.95 $μ$W/cm3 to 59 $μ$W/cm3. Hence an enhancement in fabrication process is proposed, which is termed as Backside DRIE. It helps in increasing power density without loosing an important quantity of mass. Simulations have shown that 2.5% of mass removal improves power density up to 76.71 $μ$W/cm3. Initial simulation results and problems of associated electronics are also discussed.
description: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing)
Airport service quality perception and flight delays: examining the influence of psychosituational latent traits of respondents in passenger satisfaction surveys
Creators: name: Oliveira, Alessandro V. M.
name: Oliveira, Bruno F.
name: Vassallo, Moises D.
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Economics (econ.GN)
subject: FOS: Economics and business

description: The service quality of a passenger transport operator can be measured through face-to-face surveys at the terminals or on board. However, the resulting responses may suffer from the influence of the intrinsic aspects of the respondent's personality and emotional context at the time of the interview. This study proposes a methodology to generate and select control variables for these latent psychosituational traits, thus mitigating the risk of omitted variable bias. We developed an econometric model of the determinants of passenger satisfaction in a survey conducted at the largest airport in Latin America, São Paulo GRU Airport. Our focus was on the role of flight delays in the perception of quality. The results of this study confirm the existence of a relationship between flight delays and the global satisfaction of passengers with airports. In addition, favorable evaluations regarding airports' food/beverage concessions and Wi-Fi services, but not their retail options, have a relevant moderating effect on that relationship. Furthermore, dissatisfaction arising from passengers' interaction with the airline can have negative spillover effects on their satisfaction with the airport. We also found evidence of blame-attribution behavior, in which only delays of internal origin, such as failures in flight management, are significant, indicating that passengers overlook weather-related flight delays. Finally, the results suggest that an empirical specification that does not consider the latent psychosituational traits of passengers produces a relevant overestimation of the absolute effect of flight delays on passenger satisfaction.
The Absence of Adiabatic Contraction of the Radial Dark Matter Profile in the Galaxy Cluster A2589
Creators: name: Zappacosta, Luca
name: Buote, David A.
name: Gastaldello, Fabio
name: Humphrey, Phillip J.
name: Bullock, James
name: Brighenti, Fabrizio
name: Mathews, William
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an X-ray analysis of the radial mass profile of the radio-quiet galaxy cluster A2589 between 0.015-0.25 r_vir using an XMM-Newton observation. Except for a ~16 kpc shift of the X-ray center of the R=45-60 kpc annulus, A2589 possesses a remarkably symmetrical X-ray image and is therefore an exceptional candidate for precision studies of its mass profile by applying hydrostatic equilibrium. The total gravitating matter profile is well described by the NFW model (fractional residuals
description: 15 pages, 11 figures, accepted for publication in ApJ. Minor changes to match published version
title: Debt Capacity and Debt Limits
title: A State Road Fund Perspective
titleType: Subtitle
Creators: name: Hackbart, Merl
name: Sapp, Suzanne Perkins
name: Hur, Yongbeom
Publisher: name: Kentucky Transportation Center, University of Kentucky
Year: 2004
Subjects: subject: Transportation Engineering

description: State governments are facing major transportation infrastructure financing challenges as highway or Road Fund revenue growth has slowed and resistance to tax increases has strengthened. As a result, state transportation officials have turned to other financing methods to maintain momentum in meeting highway construction and maintenance needs. Among the financing methods being considered is the expansion of bond or debt financing. Changes in federal legislation that permits states to “pre-obligate” future federal funds, among other considerations, has made debt financing an attractive alternative for the states. As states consider the expanded use of this financing strategy, several financial management questions arise including the appropriate role of debt financing, debt capacity and whether to establish limits on their use of debt financing. Unfortunately, limited research has been carried out to address these issues as the state debt financing literature has focused on state General Fund debt management issues. This study focused on the debt management issues associated with the use of state highway or Road Fund revenues as the source of debt service support for new bond issues. Among the issues assessed (through a national survey) were whether states have developed separate debt policies or limits for highway or Road Funds, the ratios of debt service payments to total state Road Fund revenues and other debt management issues. The study results suggest that the states have begun to focus on these issues and are actively setting and managing debt policies for their Road Funds and are including debt financing as part of their overall state highway financing strategies.
The Radcliffe wave parameters from data on open star clusters
Creators: name: Bobylev, Vadim V.
name: Bajkova, Anisa T.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: A spectral analysis of the vertical positions and velocities of 374 open star clusters (OSCs) was carried out. We took these OSCs from the Hunt, Reffert catalog; they have an average age of about 10 million years, and are located on the galactic plane XY in a narrow zone inclined by 25 degrees to the galactic axis Y. The following estimates of the parameters of the Radcliffe wave were obtained: a) the maximum value in periodic perturbations of vertical coordinates $Z_{max}=92\pm10$ pc with the wavelength of these perturbations $λ_z=4.82\pm0.09$ kpc; b)~maximum value of the velocity of vertical disturbances $W_{max}=4.36\pm0.12$ km s$^{-1}$ with disturbance wavelength $λ_W=1.78\pm0.02$ kpc. Note that the results of the vertical velocity analysis are first-class in accuracy and completely new.
description: 6 pages, 3 figures, Accepted to RAA