cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Microwave response of two-dimensional electron rings
Creators: name: Kovalskii, V. A
name: Gubarev, S. I.
name: Kukushkin, I. V.
name: Mikhailov, Sergey A.
name: Smet, J. H.
name: Klitzing, Klaus von
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: 530 Physik
subject: 71.35.Cc, 71.30.+h

description: We report microwave absorption studies on rings containing two-dimensional electrons. The absorption is measured on single rings with different widths using an optical luminescence technique. The dispersion of the plasmon modes has been determined in the presence of a perpendicular magnetic field. The transformation of two-dimensional plasmons in the disk geometry into plasmons with one-dimensional character in a narrow ring is addressed. Experimental data are compared with theoretical estimates based on a self-consistent solution of the Poisson and hydrodynamic equations.
Molecular CO(1-0) gas in the z~2 radio galaxy MRC 0152-209
Creators: name: Emonts, B. H. C.
name: Feain, I.
name: Mao, M. Y.
name: Norris, R. P.
name: Miley, G.
name: Ekers, R. D.
name: Villar-Martin, M.
name: Rottgering, H. J. A.
name: Sadler, E. M.
name: Rees, G.
name: Morganti, R.
name: Saikia, D. J.
name: Oosterloo, T. A.
name: Stevens, J. B.
name: Tadhunter, C. N.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We report the detection of molecular CO(1-0) gas in the high-z radio galaxy MRC 0152-209 (z = 1.92) with the Australia Telescope Compact Array Broadband Backend (ATCA/CABB). This is the third known detection of CO(1-0) in a high-z radio galaxy to date. CO(1-0) is the most robust tracer of the overall molecular gas content (including the wide-spread, low-density and subthermally excited component), hence observations of CO(1-0) are crucial for studying galaxy evolution in the Early Universe. We derive L'(CO) = (6.6 +- 2.0) x 10^10 K km/s pc^2 for MRC 0152-209, which is comparable to that derived from CO(1-0) observations of several high-z submillimetre and starforming BzK galaxies. The CO(1-0) traces a total molecular hydrogen mass of M(H2) = 5 x 10^10 (alpha_x/0.8) Msun. MRC 0152-209 is an infra-red bright radio galaxy, in which a large reservoir of cold molecular gas has not (yet) been depleted by star formation or radio source feedback. Its compact radio source is reliably detected at 40 GHz and has a steep spectral index of alpha = -1.3 between 1.4 and 40 GHz (4-115 GHz in the galaxy's rest-frame). MRC 0152-209 is part of an ongoing systematic ATCA/CABB survey of CO(1-0) in high-z radio galaxies between 1.7 < z < 3.
description: Accepted for publication in ApJL -- 8 pages, 3 figures
Safety in schools : a critical discourse analysis of policy and principal's interpretations of policy
Creators: name: Vellos, Renira E.
Publisher: name: University of British Columbia
Year: 2018

description: Responsibility for school safety falls on the shoulders of school principals, yet few studies have undertaken the task of examining policy alongside how principals interpret policy to inform their school safety practices in British Columbia (BC), Canada. Research questions that guided this study include: How is school safety recontextualized in policy texts by the BC Ministry, school boards, and school codes of conduct?; How do principals interpret policy to inform their practices of school safety? This study used critical discourse analysis (Fairclough, 2003) to examine policy texts at distinct levels of schooling including: a) BC Ministry of Education policy texts, b) School Board texts, and c) School Codes of Conduct. The analysis of policy texts made visible the narrowing of a discourse of student, as well as an emphasis on suspension as the likely consequence for a variety of misbehaviors any of which might have been deemed an “incident.” In contrast, principals’ interpretations of policy varied and the school safety practices they described as emanating from policy varied as well. Four social practices were identified through which principals’ enacted their approach to school safely. These social practices were categorized into two discretionary styles that were evident in the principals’ descriptions of school safety practices: a proactive discretionary style and a diligent discretionary style. Implications of this research include the following: First, despite a language of safe and caring schools in legislation, implementation tools from the school board and codes of conduct focused on a formulaic application of consequences with minimal consideration of intent or the circumstances surrounding behaviours; Second, policy texts positioned students simultaneously as victims, offenders, and informants, yet principals used their discretion to consider repositioning students in a range of ways including, as youths who need to be punished or as kids who made mistakes. In the disjuncture between policy texts and interviews, principals’ discretion was identified as paramount for defining school safety and the consequences imposed on students’ actions.
title: Bewahren und Verändern im Kontext biologischer und kultureller Evolution: Gaterslebener Begegnung 2003
Creators: name: :None
Publisher: name: Wissenschaftliche Verlagsgesellschaft Stuttgart
Year: 2004
Subjects: subject: Evolution
subject: Philosophie und Theorie der Biologie
subject: 570

description: Nova Acta Leopoldina: NAL ; Abhandlungen der Deutschen Akademie der Naturforscher Leopoldina, vol. 90, Nummer 338
The Markov-Zariski topology of an abelian group
Creators: name: Dikranjan, Dikran
name: Shakhmatov, Dmitri
Publisher: name: arXiv
Year: 2010
Subjects: subject: Group Theory (math.GR)
subject: Algebraic Geometry (math.AG)
subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 20A99 (Primary), 20A45, 22A05, 54H11 (Secondary)

description: According to Markov, a subset of an abelian group G of the form {x in G: nx=a}, for some integer n and some element a of G, is an elementary algebraic set; finite unions of elementary algebraic sets are called algebraic sets. We prove that a subset of an abelian group G is algebraic if and only if it is closed in every precompact (=totally bounded) Hausdorff group topology on G. The family of all algebraic subsets of an abelian group G forms the family of closed subsets of a unique Noetherian T_1 topology on G called the Zariski, or verbal, topology of G. We investigate the properties of this topology. In particular, we show that the Zariski topology is always hereditarily separable and Frechet-Urysohn. For a countable family F of subsets of an abelian group G of cardinality at most the continuum, we construct a precompact metric group topology T on G such that the T-closure of each member of F coincides with its Zariski closure. As an application, we provide a characterization of the subsets of G that are dense in some Hausdorff group topology on G, and we show that such a topology, if it exists, can always be chosen so that it is precompact and metric. This provides a partial answer to a long-standing problem of Markov.
Bhartiya Janpad Farrukhabad Ke Nagron Ka Vartman Swaroop.pdfDaridra Vyaktiyon Kee Samasyayen
Creators: name: Tomar, Neetusingh
Publisher: name: figshare
Year: 2019
Subjects: subject: Sociology
subject: FOS: Sociology

description: Bhartiya Janpad Farrukhabad Ke Nagron Ka Vartman Swaroop.pdf
Colder and Hotter: Interferometric imaging of β Cassiopeiae and α Leonis
Creators: name: Che, X.
name: Monnier, J. D.
name: Zhao, M.
name: Pedretti, E.
name: Thureau, N.
name: Merand, A.
name: Brummelaar, T. ten
name: McAlister, H.
name: Ridgway, S. T.
name: Turner, N.
name: Sturmann, J.
name: Sturmann, L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Near-infrared interferometers have recently imaged a number of rapidly rotating A-type stars, finding levels of gravity darkening inconsistent with theoretical expectations. Here, we present new imaging of both a cooler star β Cas (F2IV) and a hotter one α Leo (B7V) using the CHARA array and the MIRC instrument at the H band. Adopting a solid-body rotation model with a simple gravity darkening prescription, we modeled the stellar geometric properties and surface temperature distributions, confirming both stars are rapidly rotating and show gravity darkening anomalies. We estimate the masses and ages of these rapid rotators on L-Rpol and HR diagrams constructed for non-rotating stars by tracking their non-rotating equivalents. The unexpected fast rotation of the evolved subgiant β Cas offers a unique test of the stellar core-envelope coupling, revealing quite efficient coupling over the past ~ 0.5 Gyr. Lastly we summarize all our interferometric determinations of the gravity darkening coefficient for rapid rotators, finding none match the expectations from the widely used von Zeipel gravity darkening laws. Since the conditions of the von Zeipel law are known to be violated for rapidly rotating stars, we recommend using the empirically-derived β = 0.19 for such stars with radiation-dominated envelopes. Furthermore, we note that no paradigm exists for self-consistently modeling heavily gravity-darkened stars that show hot radiative poles with cool convective equators.
description: 34 pages, 11 figures
Carbon-doped high-mobility hole gases on (001) and (110) GaAs
Creators: name: Gerl, Christian
name: Schmult, Stefan
name: Wurstbauer, Ursula
name: Tranitz, H.-P.
name: Mitzkus, Christian
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: two-dimensional hole gas, semiconductor quantum wells, magnetoresistance, quantum Hall effect, spin-orbit interactions, gallium arsenide, III-V semiconductors
subject: 530 Physik
subject: 73.21.Fg; 73.63.Hs; 73.43.Qt; 71.70.Ej;

description: Since Stormer and Tsang have introduced the two-dimensional hole gas (2DHG) in the GaAs/AlGaAs heterosystem, the choice of suitable dopants was limited to beryllium and silicon over the last 20 years. Both acceptor atoms have significant disadvantages, i.e., either high diffusion rates or a limitation to specific growth directions. Utilizing a carbon filament doping source we prepared high-quality 2DHGs in the (001) and the nonpolar (110) crystal plane with carrier mobilies beyond 106 cm2/V s in quantum-well and single-interface structures. Low temperature magnetoresistance measurements recover a large number of fractional quantum Hall effect states and show a pronounced beating pattern from which the Rashba-induced spin splitting has been determined. In addition, 2DHGs have been grown on cleaved edges of (110) and (001) wafers with transport features in qualitative agreement with our findings on (110) substrates.
Water Lettuce (Pistia stratiotes L.) as Base Material for Composting
Creators: name: Yotaka Rattanawong
name: Nipapun Kungskulniti
name: Naowarut Charoenca
name: Lukkhana Benjawan
name: Englande, Andrew J.
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Compost
Water lettuce
Germination index

description: EnvironmentAsia, 15, 1, 70-80
Bioaccumulation of Microplastics in Fish and Snails in the Nam Pong River, Khon Kaen, Thailand
Creators: name: Sudawadee Yasaka
name: Somsak Pitaksanurat
name: Wongsa Laohasiriwong
name: Lamyai Neeratanaphan
name: Rittirong Jungoth
name: Tongpak Donprajum
name: Pongsatorn Taweetanawanit
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Microplastic accumulation
Bioaccumulation
Gastrointestinal tract
Snail soft tissue

description: EnvironmentAsia, 15, 1, 81-93
Signatures of spin in the ν=1∕3 fractional quantum Hall effect
Creators: name: Dethlefsen, A. F.
name: Mariani, E.
name: Tranitz, Hans-Peter
name: Wegscheider, Werner
name: Haug, R. J.
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: 530 Physik
subject: 73.43.Fj, 71.10.Pm, 72.25.Dc

description: The activation gap Δ of the fractional quantum Hall state at constant filling ν=1∕3 is measured in a wide range of perpendicular magnetic field B. Despite the full spin polarization of the incompressible ground state, we observe a sharp crossover between a low-field linear dependence of Δ on B and a Coulomblike square root behavior at large B. From the global gap reduction we get information about the mobility edges in the fractional quantum Hall regime.
Species discovery, evolution and kleptoplasty in marine meiofaunal flatworms
Creators: name: Stephenson, India
Publisher: name: University of British Columbia
Year: 2018

description: Rhabdocoel flatworms are abundant members of marine meiofaunal communities worldwide, contributing to a reservoir of biodiversity that thrives between grains of sand. However, they are relatively understudied due to bias in meiofaunal sampling techniques and a lack of taxonomic expertise. Here, five species of neodalyellid rhabdocoels were discovered from intertidal habitats in British Columbia and characterised with molecular and morphological data: Baicalellia solaris n. sp., Baicalellia daftpunka n. sp., Tamanawas kalipis n. sp., Pogaina paranygulgus and Baicalellia pusillus. A molecular phylogenetic analysis using maximum likelihood and Bayesian inference on concatenated 18S and 28S rDNA sequences provided a framework for revising neodalyellid systematics and for inferring character evolution within the group. Kleptoplasty, the phenomenon by which one organism steals plastids from another, was discovered in the “solar panel worms” B. solaris and P. paranygulgus, representing just the second case in metazoans; kleptoplasty has only been described previously in sacoglossan sea slugs. Using a combination of light and electron microscopy, I demonstrated that plastids were intracellularly sequestered in the parenchymal tissue. DNA barcoding of partial rbcL sequences demonstrated that the plastids were stolen from raphid pennate diatoms, which was consistent with plastid ultrastucture. Measurements of oxygen consumption demonstrated that kleptoplasts remain functional for at least ten days after sequestration in B. solaris cells. Photosynthetic activity was of a similar magnitude to a dense chlorophyte culture, indicating that photosynthetically-fixed carbon enhanced survival in light-treated compared with dark-treated flatworms. Kleptoplasts ultimately lose function and are digested; therefore, heterotrophy is required to replenish healthy populations of kleptoplasts within the host tissue. The kleptoplasts might serve as a food store, providing sustenance when seasonal diatom blooms collapse. It cannot be determined whether kleptoplasty arose once in the common ancestor of Pogaina and Baicalellia or has evolved twice convergently.
Influence of surface treatment on the magnetic properties of GaxMn1−xAs thin films
Creators: name: Maccherozzi, F.
name: Panaccione, G.
name: Rossi, G.
name: Hochstrasser, M.
name: Sperl, Matthias
name: Reinwald, Matthias
name: Woltersdorf, Georg
name: Wegscheider, Werner
name: Back, Christian H.
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: 530 Physik
subject: 75.50.Pp, 78.70.Dm, 81.40.Rs, 75.70.−i

description: We present a surface science study on carefully characterized GaxMn1−xAs films grown on GaAs(100), where we investigate the influence on magnetic properties of different surface cleaning procedures. X-ray magnetic circular dichroism reveals a net remnant magnetization along the (100) axis, after chemical etching is performed. The analysis of Mn L2,3 XAS line shapes in different environment indicates that Mn in GaxMn1−xAs behaves as a bulk impurity. By exploiting the different depth sensitivity between x-ray photoemission and x-ray absorption we observe the presence of a Mn depleted layer at the surface after etching.
Further evaluation of a THGEM UV-photon detector for RICH - comparison with MWPC
Creators: name: Peskov, V.
name: Cortesi, M.
name: Chechik, R.
name: Breskin, A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The operation of single-, double- and triple-THGEM UV-detectors with reflective CsI photocathodes (CsI-THGEM) in Ne/CH4 and Ne/CF4 mixtures was investigated in view of their potential applications in RICH. The studies were carried out with UV, x-rays and β-electrons and focused on the maximum achievable gain, discharge probability, cathode excitation effects and long-term gain stability. Comparative studies under similar conditions were made in CH4, CF4 and Ne/CF4, with a MWPC coupled to a reflective CsI photocathode (CsI-MWPC). It was found that at counting rates <= 10 Hz/mm^2 the maximum achievable gain of CsI-THGEMs is determined by the Raether limit; at counting rates > 10 Hz/mm^2 it dropped with rate. In all cases investigated the attainable CsI-THGEM gain was significantly higher than that of the CsI-MWPC, under similar conditions. Furthermore, the CsI-THGEM UV-detector suffered fewer cathode-excitation induced effects as compared to CsI-MWPC and had better stability at high counting rates.
description: 25 pages, 25 figures, paper submitted to JINST
Phase diagram of dense quark matter in QCD-like theories
Creators: name: Brauner, Tomas
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: I report the results of a series of works on the phase diagram of theories with a different number of colors and/or quarks in a different representation than in QCD. Similarities as well as differences as compared to the real world are pointed out, focusing in particular on the interplay of confinement and chiral symmetry breaking. It will be argued that recent lattice data may provide us with a clue to understand deconfinement in cold dense quark matter.
description: 3 pages, 1 pdf figure; talk at the conference "Quark Confinement and the Hadron Spectrum IX", Madrid, August 30-September 3, 2010
Ultrafast spectroscopy of the quantum Hall ferromagnet
Creators: name: Su, B.
name: Schröter, Patrick
name: Heitmann, Detlef
name: Perakis, Ilias. E.
name: Wegscheider, Werner
name: Schüller, Christian
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Ultrafast spectroscopy; Four-wave mixing; Skyrmions
subject: 530 Physik
subject: 78.47.+p

description: We report ultrafast spectroscopy experiments at the ν=1 quantum Hall state of a high-mobility two-dimensional electron system in a GaAs single quantum well. By spectrally resolved four-wave-mixing measurements we investigate the coherent dynamics of photo-excited electron–hole pairs and find extraordinarily long decoherence times for electrons in the upper spin level around ν=1. We interpret the observed slower decrease of the dephasing time for ν>1, as compared to ν<1, as a fingerprint of Skyrmion formation dynamics.
Pyrethroid and Heavy Metal Residues in Different Coffee Bean Preparation Processes and Human Health Risk Assessments via Consumption
Creators: name: Paphatsara Khunlert
name: Kanjana Imsilp
name: Amnart Poapolathep
name: Saranya Poapolathep
name: Phanwimol Tanhan
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Coffee
Health risk
Heavy metals
Pyrethroid
Residues

description: EnvironmentAsia, 15, 1, 94-108
Detecting dementia from written and spoken language
Creators: name: Masrani, Vaden
Publisher: name: University of British Columbia
Year: 2018

description: This thesis makes three main contributions to existing work on the automatic detection of dementia from language. First we introduce a new set of biologically motivated spatial neglect features, and show their inclusion achieves a new state of the art in classifying Alzheimer's disease (AD) from recordings of patients undergoing the Boston Diagnostic Aphasia Examination. Second we demonstrate how a simple domain adaptation algorithm can be used to leveraging AD data to improve classification of mild cognitive impairment (MCI), a condition characterized by a slight-but-noticeable decline in cognition that does not meet the criteria for dementia, and a condition for which reliable data is scarce. Third, we investigate whether dementia can be detected from written rather than spoken language, and show a range of classifiers achieve a performance far above baseline. Additionally, we create a new corpus of blog posts written by authors with and without dementia and make it publicly available for future researchers.
General properties of multiparton webs: proofs from combinatorics
Creators: name: Gardi, Einan
name: White, Chris D.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Recently, the diagrammatic description of soft-gluon exponentiation in scattering amplitudes has been generalized to the multiparton case. It was shown that the exponent of Wilson-line correlators is a sum of webs, where each web is formed through mixing between the kinematic factors and colour factors of a closed set of diagrams which are mutually related by permuting the gluon attachments to the Wilson lines. In this paper we use replica trick methods, as well as results from enumerative combinatorics, to prove that web mixing matrices are always: (a) idempotent, thus acting as projection operators; and (b) have zero sum rows: the elements in each row in these matrices sum up to zero, thus removing components that are symmetric under permutation of gluon attachments. Furthermore, in webs containing both planar and non-planar diagrams we show that the zero sum property holds separately for these two sets. The properties we establish here are completely general and form an important step in elucidating the structure of exponentiation in non-Abelian gauge theories.
description: 38 pages, 10 figures
Electric current-induced spin orientation in quantum well structures
Creators: name: Ganichev, Sergey
name: Danilov, Sergey
name: Schneider, Petra
name: Belkov, Vassilij
name: Golub, Leonid E.
name: Wegscheider, Werner
name: Weiss, Dieter
name: Prettl, Wilhelm
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Electric spin orientation; Spin–orbit splitting; Spin relaxation
subject: 530 Physik
subject: 72.25.Pn; 85.75.−d; 78.67.De

description: A longstanding theoretical prediction is the orientation of spins by an electrical current flowing through low-dimensional carrier systems of sufficiently low crystallographic symmetry. Here we show by means of terahertz transmission experiments through two-dimensional hole systems a growing spin orientation with an increasing current at room and liquid nitrogen temperatures.
Classical linear vector optimization duality revisited
Creators: name: Bot, Radu Ioan
name: Grad, Sorin-Mihai
name: Wanka, Gert
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 90C05, 90C25, 90C29

description: With this note we bring again into attention a vector dual problem neglected by the contributions who have recently announced the successful healing of the trouble encountered by the classical duals to the classical linear vector optimization problem. This vector dual problem has, different to the mentioned works which are of set-valued nature, a vector objective function. Weak, strong and converse duality for this "new-old" vector dual problem are proven and we also investigate its connections to other vector duals considered in the same framework in the literature. We also show that the efficient solutions of the classical linear vector optimization problem coincide with its properly efficient solutions (in any sense) when the image space is partially ordered by a nontrivial pointed closed convex cone, too.
description: 10 pages
Effects of PM2.5 on the Incidence of Circulatory System Diseases in Muang District, Khon Kaen Province of Northeast Thailand
Creators: name: Pornpun Sakunkoo
name: Pornsuda Manochai
name: Koh, David
name: Sarawut Sangkham
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Circulatory diseases
PM2.5
Temperature
Relative humidity
Khon Kaen Province

description: EnvironmentAsia, 15, 1, 109-116
Assessment of Performance and Emissions Characteristics of Diesel Engine using Water Diesel Emulsion: A Review
Creators: name: A. Mostafa
name: Mustafa, Ahmad
name: I. Youssef
name: M. Mourad
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Emissions characteristics
Engine performance
Micro-explosion phenomenon
Water-diesel emulsion

description: EnvironmentAsia, 15, 1, 117-130
Volatile Organic Compounds from Unexpected Sources: Fabric Softener-Initiated Emissions
Creators: name: Thabtim Chatsuvan
name: Sahalaph Homwuttiwong
name: Morris, John
name: Maneerat Ongwandee
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Emission
Total volatile organic compounds
Fabrics
Fabric softener
Sorption

description: EnvironmentAsia, 15, 1, 131-141
Spectral data for doubly excited states of helium with non-zero total angular momentum
Creators: name: Eiglsperger, Johannes
name: Schönwetter, Moritz
name: Piraux, Bernard
name: Madroñero, Javier
Publisher: name: arXiv
Year: 2011
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: A spectral approach is used to evaluate energies and widths for a wide range of singlet and triplet resonance states of helium. Data for total angular momentum $L=1,...,4$ is presented for resonances up to below the 5th single ionization threshold. In addition the expectation value of $\cos(θ_{12})$ is given for the calculated resonances.
description: 35 pages, 16 tables, to be published in Atomic Data and Nuclear Data Tables
Magnetoresistance oscillations in GaAs/AlGaAs superlattices subject to in-plane magnetic fields
Creators: name: Smrčka, L.
name: Vašek, P.
name: Svoboda, P.
name: Gonharuk, N. A.
name: Pacherová, O.
name: Krupko, Yu.
name: Sheikin, Y.
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Superlattice; Fermi surface; Magnetoresistance
subject: 530 Physik
subject: 73.43.Qt; 03.65.Sq

description: The MBE-grown GaAs/AlGaAs superlattice with Si-doped barriers has been used to study a 3D→2D transition under the influence of the in-plane component of an applied magnetic field. The longitudinal magnetoresistance data measured in tilted magnetic fields have been interpreted in terms of a simple tight-binding model. The data provide values of basic parameters of the model and make it possible to reconstruct the superlattice Fermi surface and to calculate the density of states for the lowest Landau subbands. Positions of van Hove singularities in the DOS agree excellently with magnetoresistance oscillations, confirming that the model describes adequately the magnetoresistance of strongly coupled semiconductor superlattices.
Supplementary materials for World Mycotoxin Journal: Quantitative risk assessment for aflatoxins in beans from northern Tanzania
Creators: name: Nyangi, C.
name: Runyogote, J.
name: Mng’ong’o, M.
Publisher: name: Brill Online
Year: 2024
Subjects: classificationCode: 300605
subject: Food safety, traceability, certification and authenticity
classificationCode: 321099
subject: Nutrition and dietetics not elsewhere classified

description: The study focussed on quantitative risk assessment for population exposure to aflatoxins by consuming beans from bean farmers in three villages; Long, Sabilo and Seloto in Babati District, Northern Tanzania. Aflatoxin levels were determined in a total of 144 beans samples; a total of 38 samples were collected from harvesting beans, while 106 samples were collected from stored beans. This kind of assessment allows modelling beans consumption data (kg/kg body weight (bw)/day) using an estimated average weight of an adult of 60 kg with previously collected data for total aflatoxin (AF) contamination (µg/kg) beans samples from the year 2013/14 survey. Consumption was estimated by using the minimum annual per capita consumption of beans in Tanzania of 13.02 kg (which is equivalent to 35.67 g/day) and the exposure assessment was performed with the @RISK analysis software. Results from the assessment showed exposure for lower bound (LB) having a mean value of 1.06, 0.79 and 0.95 ng/kg bw/day in Long, Sabilo and Seloto villages, respectively, while for medium bound (MB) the mean values were 1.33, 1.07 and 1.26 ng/kg bw/day, respectively, and for upper bound (UB) the values were 1.65, 1.38 and 1.58 ng/kg bw/day, respectively. The margins of exposure (MoE) from this study were below 10,000 for all scenarios and this is of public health concern. Even though all samples had aflatoxin contamination below the maximum tolerable limit (MTL) of 4, 10 and 20 µg/kg for aflatoxins in cereals and pulses in the EU, the East African Community (EAC) and the USA, there is still a serious long-term health implication. Meeting MTL will not by itself guarantee food safety, but using the data collected and available on various health effects from aflatoxin and other mycotoxins, it is important to incorporate them into a risk assessment and show how excessive consumption of foods meeting MTLs can still carry significant public health risks.
The anyon model: an example inspired by string theory
Creators: name: Talalov, S. V.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We investigate the enlarged class of open finite strings in $(2+1)D$ space-time. The new dynamical system related to this class is constructed and quantized here. As the result, the energy spectrum of the model is defined by a simple formula ${\sf S} = α_n{\sf E} + c_n$; the spin ${\sf S}$ is an arbitrary number here but the constants $α_n$ and $c_n$ are eigenvalues for certain spectral problems in fermionic Fock space ${\bf H}_ψ$ constructed for the free 2D fermionic field.
description: 19 pages; to be published in Int. Journ. of Mod. Phys. A
Model Feasibility of Air Pollution Treatment Using Plants as Filter by Computational Fluid Dynamic (CFD) Analysis: A Case Study in Laboratory
Creators: name: Winai Meesang
name: Erawan Baothong
name: Sahassawas Poojeera
name: Wiwat Kaenka
name: Ssawai Mathapha
name: Aphichat Srichat
name: Chaiyan Junsiri
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: CFD
Plants as filter
Air pollution treatment
Treatment model
Zigzags panels

description: EnvironmentAsia, 15, 1, 142-153
Group Anonymity
Creators: name: Chertov, Oleg
name: Tavrov, Dan
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: In recent years the amount of digital data in the world has risen immensely. But, the more information exists, the greater is the possibility of its unwanted disclosure. Thus, the data privacy protection has become a pressing problem of the present time. The task of individual privacy-preserving is being thoroughly studied nowadays. At the same time, the problem of statistical disclosure control for collective (or group) data is still open. In this paper we propose an effective and relatively simple (wavelet-based) way to provide group anonymity in collective data. We also provide a real-life example to illustrate the method.
description: 10 pages, 2 tables. Published by Springer in "Information Processing and Management of Uncertainty in Knowledge-Based Systems. Applications". The final publication is available at http://www.springerlink.com/content/u701148783683775/
Mixed flux-equipartition solutions of a diffusion model of nonlinear cascades
Creators: name: Connaughton, Colm
name: McAdams, Rachel
Publisher: name: arXiv
Year: 2011
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We present a parametric study of a nonlinear diffusion equation which generalises Leith's model of a turbulent cascade to an arbitrary cascade having a single conserved quantity. There are three stationary regimes depending on whether the Kolmogorov exponent is greater than, less than or equal to the equilibrium exponent. In the first regime, the large scale spectrum scales with the Kolmogorov exponent. In the second regime, the large scale spectrum scales with the equilibrium exponent so the system appears to be at equilibrium at large scales. Furthermore, in this equilibrium-like regime, the amplitude of the large-scale spectrum depends on the small scale cut-off. This is interpreted as an analogue of cascade nonlocality. In the third regime, the equilibrium spectrum acquires a logarithmic correction. An exact analysis of the self-similar, non-stationary problem shows that time-evolving cascades have direct analogues of these three regimes.
description: 4 pages
Few-electron quantum dot fabricated with layered scanning force microscope lithography
Creators: name: Sigrist, Martin
name: Gustavsson, S.
name: Ihn, Thomas
name: Ensslin, Klaus
name: Driscoll, D.
name: Gossard, A. C.
name: Reinwald, Matthias
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Few-electron quantum dot; Layered lithography; Scanning force microscope
subject: 530 Physik
subject: 73.23.Hk; 73.63.Kv; 73.21.La

description: Few-electron quantum dots with integrated charge read-out have been fabricated by layered local anodic oxidation of a Ga[Al]As heterostructure and a thin Titanium top gate. The additional set of gates provided by the metallic film is used to tune the quantum dots into the few-electron regime. Current through the quantum dots and the quantum dot charge have been simultaneously measured for electron numbers varying between zero and two. The singlet–triplet splitting varies in two different samples between 0.5 and 1.5 meV. The Zeeman splitting of the first conductance resonance is observed in parallel magnetic field. The high tunability and straightforward implementation of these structures are promising for future nanostructure design.
Influence of an in situ-deposited SiNx intermediate layer inside GaN and AlGaN layers on SiC substrates
Creators: name: Engl, Karl
name: Beer, Martin
name: Gmeinwieser, Nikolaus
name: Schwarz, Ulrich
name: Zweck, Josef
name: Wegscheider, Werner
name: Miller, Stephan
name: Miler, A.
name: Lugauer, H.-J.
name: Brüderl, G.
name: Lell, Alfred
name: Härle, Volker
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: A1. Characterization; A1. Defects; A l. Dislocation; A1. Etching; B l. GaN
subject: 530 Physik
subject: 78.55.Cr; 81.15.Gh; 61.72.Ff; 68.35.Gy; 68.55.Jk

description: In this work we present a study on the influence of an in situ grown SiNx intermediate layer inside (Al)GaN epitaxial layers grown on SiC substrates on dislocation densities and material strain of the epitaxial films. A defect density of View the MathML source was achieved by reducing the number of pure edge dislocations in the order of one magnitude. It was found that a reduction of the dislocation density is only successful by inserting the SiNx layer inside GaN films and no defect reduction takes place with SiNx inside AlGaN films. The presence of stacking faults at the close vicinity of the SiNx layer plays an important role for the mechanism of dislocation termination at the SiNx interface. To determine dislocation densities an etch pit density method was carried out combining transmission electron microscopy (TEM) investigations of plan-view samples with atomic force microscopy (AFM) scans. Structural properties were investigated by cross-sectional TEM samples. Composition of AlGaN at the SiNx interface was determined by energy dispersive X-ray analysis (EDX) and secondary ion mass spectroscopy (SIMS). Material strain was investigated by micro-photoluminescence measurements (μ-PL).
Tuning of tunneling rates in quantum dots using a quantum point contact
Creators: name: Rogge, M. C.
name: Fricke, C.
name: Harke, B.
name: Hohls, F.
name: Haug, R. J.
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Quantum dots; Quantum point contact; Charge detection; Tunneling rates; Excited states
subject: 530 Physik
subject: 73.63.Kv; 73.23.Hk; 72.20.My

description: We study the influence of asymmetric tunneling rates of a lateral quantum dot connected to source and drain leads. We use a quantum point contact (QPC) to detect charging events on the dot. Since the mean charge depends on the ratio of the tunneling rates the QPC can be used to detect symmetric configurations where both rates are equal. Thus, the transport properties of the dot can be investigated concerning this symmetry. We concentrate on the visibility of features that correspond to transitions with excited states. We interpret the results with the number of channels used for transport, the electron flow direction and the rate symmetry.
A Coarse-Grained Biophysical Model of E. coli and Its Application to Perturbation of the rRNA Operon Copy Number
Creators: name: Tadmor, Arbel D.
name: Tlusty, Tsvi
Publisher: name: arXiv
Year: 2010
Subjects: subject: Molecular Networks (q-bio.MN)
subject: Biological Physics (physics.bio-ph)
subject: Biomolecules (q-bio.BM)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: We propose a biophysical model of Escherichia coli that predicts growth rate and an effective cellular composition from an effective, coarse-grained representation of its genome. We assume that E. coli is in a state of balanced exponential steadystate growth, growing in a temporally and spatially constant environment, rich in resources. We apply this model to a series of past measurements, where the growth rate and rRNA-to-protein ratio have been measured for seven E. coli strains with an rRNA operon copy number ranging from one to seven (the wild-type copy number). These experiments show that growth rate markedly decreases for strains with fewer than six copies. Using the model, we were able to reproduce these measurements. We show that the model that best fits these data suggests that the volume fraction of macromolecules inside E. coli is not fixed when the rRNA operon copy number is varied. Moreover, the model predicts that increasing the copy number beyond seven results in a cytoplasm densely packed with ribosomes and proteins. Assuming that under such overcrowded conditions prolonged diffusion times tend to weaken binding affinities, the model predicts that growth rate will not increase substantially beyond the wild-type growth rate, as indicated by other experiments. Our model therefore suggests that changing the rRNA operon copy number of wild-type E. coli cells growing in a constant rich environment does not substantially increase their growth rate. Other observations regarding strains with an altered rRNA operon copy number, such as nucleoid compaction and the rRNA operon feedback response, appear to be qualitatively consistent with this model. In addition, we discuss possible design principles suggested by the model and propose further experiments to test its validity.
Analytical Approach to Deforestation Effect on Climate Change Using Metadata in Thailand
Creators: name: Kanchanit Kamolrattanakul
name: Kanita Tungkananuruk
name: Thitima Rungratanaubon
name: Chalisa Veesommai Sillberg
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Forest loss
Human driving forces
Environmental and information analysis
Statistical process

description: EnvironmentAsia, 15, 1, 154-165
Transport in a shunted surface superlattice with a perpendicular magnetic field
Creators: name: Feil, Thomas
name: Tranitz, Hans-Peter
name: Gerl, Christian
name: Wegscheider, Werner
Publisher: name: Universität Regensburg
Year: 2006
Subjects: subject: Cleaved-edge-overgrowth; Superlattice; Bloch oscillations; Magnetic field
subject: 530 Physik
subject: 73.21.Cd; 73.63.Hs

description: We experimentally investigate the transport through a shunted surface superlattice under the influence of a magnetic field applied perpendicular to the current direction. The current–voltage characteristics of these surface superlattices exhibit a peak which is followed by a wide region of negative differential resistance. The application of a transverse magnetic field has a profound influence on the position and height of this peak. The recorded shifts are compared to the predictions of different superlattice transport theories. Since these theories predict a different dependence on the magnetic field strength, the transport mechanism in the surface superlattice structures can be uniquely determined.
Aharonov-Bohm interferences from local deformations in graphene
Creators: name: de Juan, Fernando
name: Cortijo, Alberto
name: Vozmediano, María A. H.
name: Cano, Andrés
Publisher: name: arXiv
Year: 2011
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: One of the most interesting aspects of graphene is the tied relation between structural and electronic properties. The observation of ripples in the graphene samples both free standing and on a substrate has given rise to a very active investigation around the membrane-like properties of graphene and the origin of the ripples remains as one of the most interesting open problems in the system. The interplay of structural and electronic properties is successfully described by the modelling of curvature and elastic deformations by fictitious gauge fields that have become an ex- perimental reality after the suggestion that Landau levels can form associated to strain in graphene and the subsequent experimental confirmation. Here we propose a device to detect microstresses in graphene based on a scanning-tunneling-microscopy setup able to measure Aharonov-Bohm inter- ferences at the nanometer scale. The interferences to be observed in the local density of states are created by the fictitious magnetic field associated to elastic deformations of the sample.
description: Some bugs fixed
Auf dem Forum. Die temporäre Platznutzung in antiken Städten Italiens
Creators: name: Bossert, Lukas C.
Publisher: name: Zenodo
Year: 2019
Subjects: Reconstruction
Temporal architecture
Pits
Forum
Italy
Late Republic

description:

Public, social life in the ancient city culminated on the forum: that this was facilitated by a pragmatic appropriation of the built architectural space surrounding the forum forms the underlying foundation of this thesis. This socio-cultural function of forum architecture is analyzed for (selected) cities of the Italian peninsula of the Late Republic and Early Imperial period. The focus is on the utilitarian dimension of the built structures of the public space – that is, how the architectural configuration of fora influenced the parameters of its use.

The main archaeological evidence for the construction of temporary structures is provided by the discovery of series of systematically positioned pits on Italian fora. Here, the pits are classified and used as the foundation for structural calculations in order to reconstruct the various architectural possibilities as 3D models.

Probable temporary constructions are reconstructed based on the evidence of pits for the fora of Paestum, Cosa and Alba Fucens. On each of these fora, the reconstruction of 'electoral bridges' (pontes), landings and stands are possible.

The impact on the sensory perception of these spaces as a result of the temporary wooden structures thus obtained are then analyzed, with a focus on movement, acoustics, sound, and climate. The acoustic and visual perception for those spaces where temporary structures can be reconstructed is improved in comparison with the permanent structures. The forum itself is thus characterized by differing strategies of use.

These strategies continued to be in use over a long period and, with time, the experience gained led to structural improvements of the temporary constructions. Changes to the pits can be correlated to social (and not necessarily political) reorganizations, whereby new buildings began to assume the functions of the fora. The pits therefore provide evidence for an increase in functional differentiation within architecture and society in the Late Republic.
description: Unofficial but authorised version of my PhD thesis.
Geothermal Heat Pump as an Environmental Friendly, Renewable Energy Source for Sustainable Pig Production
Creators: name: Hong-Seok Mun
name: Dilawar, Muhammad Ammar
name: Chong-Dae Kim
name: Sang-Bum Ryu
name: Jong-Pil Moon
name: Chul-Ju Yang
Publisher: name: Thai Society of Higher Education Institutes on Environment
Year: 2022
Subjects: Electricity consumption
Pig barn
Greenhouse gas emission
Rural development

description: EnvironmentAsia, 15, 1, 166-173
A novel telehealth program for the treatment of pediatric overweight and obesity : a program evaluation
Creators: name: Lasinsky, Anne Marice
Publisher: name: University of British Columbia
Year: 2018

description: Introduction: High rates of overweight and obesity among children in Canada have created the need for new and innovative strategies to treat the condition and address its underlying causes. Telehealth is an attractive option to reach children and families with barriers to accessing in-person treatment programs. The HealthLink BC Eating and Activity Program for Kids (the Program), a provincial telehealth program staffed by registered dietitians and a qualified exercise professional, was launched in Spring 2015 in British Columbia, Canada. A comprehensive program evaluation was implemented to assess its first 24-months of operation. Purpose: The purpose of this program evaluation was to assess the effectiveness of a telephone-based childhood obesity treatment program in its initial implementation phase. Methods: Participant data was obtained from physician referrals to the Program and/or information obtained at intake and upon follow-up (3 and 6 mo). Data includes the scores from a battery of questionnaires measuring: diet, eating behaviours, sleep, physical activity and sedentary behaviour, self-perception, and personal strengths and difficulties. Other data includes height, weight, body mass index (BMI), waist circumference, blood pressure, and the extent of contact with the Program. Baseline measurements were compared with follow-up data obtained after Program completion at 3 and 6 mo. Results: A total of 55 participants consented to participating in the Program evaluation (25.5% of all referrals). Children in the evaluation generally adhered to the Program, with 56.4% of participants completing at least 70% (5 weekly calls) of the Program. At the 3-month follow-up: participants reduced their consumption of processed grain and meat iii products, boys increased their fruit and vegetable consumption, both boys and girls increased total and moderate-to-vigorous physical activity, and reduced their time spent in sedentary pursuits. There were no changes observed in BMI. At 6-months post-intervention, some improvements in diet and physical activity had diminished. Results were impacted by small sample sizes and high variability across the sample. Conclusion: The Program succeeded at attracting and retaining children and teens referred to its telehealth services. Like many other intervention programs, participants reported modest improvements immediately post-intervention, but generally did not report maintaining positive changes.