cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Conformal cloak for waves
Creators: name: Chen, Huanyang
name: Leonhardt, Ulf
name: Tyc, Tomas
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Conformal invisibility devices are only supposed to work within the validity range of geometrical optics. Here we show by numerical simulations and analytical arguments that for certain quantized frequencies they are nearly perfect even in a regime that clearly violates geometrical optics. The quantization condition follows from the analogy between the Helmholtz equation and the stationary Schrodinger equation.
description: 4 pages, 3 figures
Inert Phosphorescent Nanospheres as Markers for Optical Assays
Creators: name: Kürner, Jens M.
name: Klimant, Ingo
name: Krause, Christian
name: Preu, Harald
name: Kunz, Werner
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 2001
Subjects: subject: 540 Chemie

description: A simple encapsulation technique is presented to produce highly phosphorescent, inert nanospheres that are suitable luminescent markers. It is based on the coprecipitation of phosphorescent ruthenium(II)-tris(polypyridyl) complexes and polyacrylonitrile (PAN) derivatives from a solution in N,N-dimethylformamide. The beads precipitate in the form of very small aggregates of spherical shape and a typical particle diameter of less than 50 nm. This process allows the encapsulation of phosphorescent and fluorescent dyes in an individual nanosphere provided that they are sufficiently lipophilic. Quenching by oxygen is negligible due to the use of PAN. The nanospheres were characterized with respect to their spectral properties (quantum yields of the luminophores, brightness, luminescence decay time), stability in aqueous buffered suspensions, and in terms of size, shape, and surface charge of the particles, as well as storage stability, quenching by oxygen, and dye leaching.
Fractional and semi-local non-Abelian Chern-Simons vortices
Creators: name: Gudnason, Sven Bjarke
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper we study fractional as well as semi-local Chern-Simons vortices in G = U(1) x SO(2M) and G = U(1) x USp(2M) theories. The master equations are solved numerically using appropriate Ansatze for the moduli matrix field. In the fractional case the vortices are solved in the transverse plane due to the broken axial symmetry of the configurations (i.e. they are non-rotational invariant). It is shown that unless the fractional vortex-centers are all coincident (i.e. local case) the ring-like flux structure, characteristic of Chern-Simons vortices, will become bell-like fluxes - just as those of the standard Yang-Mills vortices. The asymptotic profile functions are calculated in all cases and the effective size is identified.
description: LaTeX, 38 pages, 16 figures.
THE SPREAD OF ISLAM AND MUSLIM LAW DURING THE ARAB INVASION
Creators: name: Xidirov Davlatbek Anzor ugli
Publisher: name: Zenodo
Year: 2023

description: The spread of Islam and Muslim law during the Arab conquest is an important chapter in world history and represents a period of change that changed the political, cultural and legal landscapes of various regions. The Arab conquests spanning the 7th and 9th centuries led to the unification of the Arabian Peninsula under the banner of Islam and the rapid spread of Islamic rule over a vast area that included parts of the Middle East, North Africa, and Europe. This expansion of Islamic influence contributed to the spread of Islamic legal principles and the implementation of Muslim law, ultimately leaving a deep mark on the development of Islamic civilization and its legal traditions. This article examines the spread of Islam and Muslim law during the Arab conquest.
Looking for a charge asymmetry in cosmic rays
Creators: name: Masina, Isabella
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We combine the data from PAMELA and FERMI-LAT cosmic ray experiments by introducing a simple sum rule. This allows to investigate whether the lepton excess observed by these experiments is charge symmetric or not. We also show how the data can be used to predict the positron fraction at energies yet to be explored by the AMS-02 experiment.
description: Contribution to the proceedings of DISCRETE 2010, 5 pages, 2 figures
Ammonia fluorosensors based on reversible lactonization of polymer-entrapped rhodamine dyes, and the effects of plasticizers
Creators: name: Preininger, Claudia
name: Mohr, Gerhard J.
name: Klimant, Ingo
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1996
Subjects: subject: Optode; Sensors; Rhodamine B
subject: 540 Chemie

description: A new kind of optical sensor for monitoring dissolved ammonia uses rhodamines immobilized in thin membranes made from ethylcellulose, poly(vinyl chloride) or poly(vinyl acetate). The response to ammonia is the result of a change in the molecular structure of the rhodamine. On exposure to ammonia, the rhodamine is converted to a colorless and non-fluorescent lactone. As a result, fluorescence intensity is reduced. The polymer not only has a strong effect on the limits of detection, but also on the response time. Typical LODs are 0.1 μg ml−1 for ethylcellulose and poly(vinyl chloride), but as low as 10 μg ml−1 for poly(vinyl acetate). The last membranes provide highest sensitivity and lowest detection limits, but are not suitable for online monitoring of ammonia because they respond irreversibly. They may be applied, however, for “single shot” tests. Response times of the membranes are in the order of 2–5 min.
Torsion of elliptic curves over quadratic cyclotomic fields
Creators: name: Najman, Filip
Publisher: name: arXiv
Year: 2010
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: In this paper we study the possible torsions of elliptic curves over $\mathbb Q(i)$ and $\mathbb Q(\sqrt {-3})$.
description: 9 pages, to appear in Math. J. Okayama Univ.
Chiroptic recognition of potassium ion
Creators: name: Wolfbeis, Otto S.
name: Opitz, Dieter
name: Werner, Tobias
name: Ouart, Andrè
Publisher: name: Universität Regensburg
Year: 2001
Subjects: subject: molecular recognition; valinomycin; potassium sensing; chiral sensing; circular dichroism; optical rotatory dispersion; fluorescence
subject: 540 Chemie

description: The high specificity in the recognition and specific binding of potassium ion by the depsipeptide valinomycin (VM) is exploited for its recognition and quantitation using both circular dichroism (CD) and optical rotation dispersion (ORD). The specific rotation of VM is comparably small (2.34 deg ml g⁻¹ cm⁻¹), so that an 8 µM (= 8.89 mg ml⁻¹) solution of VM in 95% ethanol rotates polarized light of Λ = 426 nm passing a 2 cm cuvette by 0.076° only. It is shown, however, that VM undergoes large changes in both ORD and CD on binding to potassium ion. VM, potassium ion and the anionic dye merocyanine 540 form a ternary complex (VM/K/MC) which displays an induced CD with a positive maximum at 488 nm and a negative maximum at 470 nm. The ternary complex also displays fluorescence that is weaker by about 30% when compared to that of the dye alone. The induced CD of the ternary complex is interpreted in terms of the large conformational change which VM is known to undergo on binding potassium ion, thereby forming the prerequisite for a van der Waals interaction between its outwardly directed lipophilic domains and the lipophilic domains of the anionic dye. The method is likely to be applicable to the fluorescent detection of all kinds of ions for which chiral receptors are known, e.g. in studies on the role of ions in biological systems including ion channels.
Lichnerowicz cocycles and central Lie group extensions
Creators: name: Vizman, Cornelia
Publisher: name: arXiv
Year: 2010
Subjects: subject: Differential Geometry (math.DG)
subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics
subject: 58B20

description: We present a geometric construction of central extensions of covering groups of the group of volume preserving diffeomorphisms, integrating central extensions of the Lie algebra of divergence free vector fields defined by Lichnerowicz cocycles. Certain covering spaces of non-linear Grassmannians can be realized as prequantizable coadjoint orbits in these Lie group extensions.
description: 10 pages
Probing the Polarity of Sol-Gels and Ormosils via the Absorption of Nile Red
Creators: name: Lobnik, Aleksandra
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 2001
Subjects: subject: characterization - polarity sensitive dyes - sol-gels - ormosils - absorption - stability
subject: 540 Chemie

description: Conventional sol-gels are rather hydrophilic. A more hydrophobic material is obtained preparing organically modified siloxanes (ormosils). The polarity-sensitive probe Nile Red (NR) was doped in various sol-gels to probe their micro-polarity. The experiments show that the NR is an excellent probe and sensitive to the polarity of its microenvironment. Spectroscopic studies reveal remarkable changes in the absorption band positions and intensities as a function of the polarity of the sol-gel, which depends on the different precursors used. Furthermore, sol aging, gelation and temporal stability as a function of different ormosils have been investigated.
Fiber-optic microsensor for high resolution pCO₂ sensing in marine environment
Creators: name: Neurauter, Gerhard
name: Klimant, Ingo
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 540 Chemie

description: A fast responding fiber-optic microsensor for sensing pCO2 in marine sediments with high spatial resolution is presented. The tip diameter varies typically between 20 and 50 μm. In order to make the pH-indicator ¶8-hydroxypyrene-1,3,6-trisulfonate soluble in the ethyl cellulose matrix, it was lipophilized with tetraoctylammonium as the counterion [HPTS-(TOA)4]. The microsensor was tuned to sense very low levels of dissolved carbon dioxide which are typically present in marine systems. The detection limit is 0.04 hPa pCO2 which corresponds to 60 ppb CO2 of dissolved carbon dioxide. A soluble Teflon derivative with an extraordinarily high gas permeability was chosen as a protective coating to eliminate interferences by ionic species like chloride or pH. Response times of less than 1 min were observed. The performance of the new microsensor is described with respect to reproducibility of the calibration curves, dynamic range, temperature behavior, long term stability and storage stability. The effect of hydrogen sulfide as an interferent, which is frequently present in anaerobic sediment layers, was studied in detail.
PENTINGNYA ETIKA DALAM BERBISNIS
Creators: name: NOVA RIZA
Publisher: name: Zenodo
Year: 2022

description: TUGAS UAS MATA KULIAH KEWIRAUSAHAAN | MAKALAH INDIVIDU | "PENTINGNYA ETIKA DALAM BERBISNIS" Nova Riza ( 11812056 )| Mahasiswa PBA Kelas 7C FTIK-IAIN PONTIANAK | Dosen Pengampu : Dr. H. Fachrurazi, S.Ag., MM dan Yulida, S.E., MM
Polarization immunoassays using reactive ruthenium metal-ligand complexes as luminescent labels
Creators: name: Dürkop, Axel
name: Lehmann, Frank
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 2002
Subjects: subject: Ruthenium metal-ligand complex ·Polarization probe ·Fluorescence polarization immunoassay
subject: 540 Chemie

description: The first competitive fluorescence polarization immunoassay using ruthenium metal-ligand complexes (5-MC and 55-DC) as labels is described. These were newly synthesized and characterized in terms of their spectra, their covalent linkage to proteins, and their use in both homogeneous and competitive immunoassays. Linkage to proteins was achieved by the N-hydroxysuccinimide ester method, which was demonstrated for the systems HSA-anti-HSA and myoglobin-anti-myoglobin. The values of the fundamental polarization are 0.18 for 5-MC and 0.33 for 55-DC. Polarization immunoassays with labeled HSA and myoglobin were performed in the homogeneous format and resulted in an increase of the fluorescence polarization of up to 100%. In the competitive assay, a decrease in polarization of >90% was detectable. When the competitive HSA immunoassay was validated against an independent test both methods gave almost the same results.
Quantum Mechanical Simulation of Electronic Transport in Nanostructured Devices by Efficient Self-consistent Pseudopotential Calculation
Creators: name: Jiang, Xiang-Wei
name: Li, Shu-Shen
name: Xia, Jian-Bai
name: Wang, Lin-Wang
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a new empirical pseudopotential (EPM) calculation approach to simulate the million atom nanostructured semiconductor devices under potential bias using the periodic boundary conditions. To treat the non-equilibrium condition, instead of directly calculating the scattering states from the source and drain, we calculate the stationary states by the linear combination of bulk band method and then decompose the stationary wave function into source and drain injecting scattering states according to an approximated top of the barrier splitting (TBS) scheme based on physical insight of ballistic and tunneling transport. The decomposed electronic scattering states are then occupied according to the source/drain Fermi-Levels to yield the occupied electron density which is then used to solve the potential, forming a self-consistent loop. The TBS is tested in an one-dimensional effective mass model by comparing with the direct scattering state calculation results. It is also tested in a three-dimensional 22 nm double gate ultra-thin-body field-effect transistor study, by comparing the TBS-EPM result with the non-equilibrium Green's function tight-binding result. We expected the TBS scheme will work whenever the potential in the barrier region is smoother than the wave function oscillations and if it does not have local minimum, thus there is no multiple scattering as in a resonant tunneling diode, and when a three-dimensional problem can be represented as a quasi-one-dimensional problem, e.g., in a variable separation approximation. Using our approach, a million atom non-equilibrium nanostructure device can be simulated with EPM on a single processor computer.
Luminescence Lifetime Temperature Sensing Based on Sol-Gels and Poly(acrylonitrile)s Dyed with Ruthenium Metal–Ligand Complexes
Creators: name: Liebsch, Gregor
name: Klimant, Ingo
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: 540 Chemie

description: Temperature-sensitive materials based on the temperature probe ruthenium-tris-1,10-phenathroline (Ru(phen)) are presented. As its luminescence, the intensity and decay time of which are both temperature sensitive, is quenched by oxygen, Ru(phen) needs to be encapsulated in materials with very low permeability to molecular oxygen. Its incorporation into sol-gels and poly(acrylonitrile)s (PANs) is investigated here and it is shown that the resulting materials can be deposited onto optical fibers for use as temperature optodes.
The role of health literacy in chronic respiratory disease management
Creators: name: Shum, Jessica
Publisher: name: University of British Columbia
Year: 2017

description: Background: Health literacy (HL) is defined as the ability to access, understand, evaluate, communicate, and use health information to make informed health decisions. Studies have reported a relationship between low HL and less health-related knowledge, poorer skills in taking medication, and treatment non-adherence. Despite this, measurement of HL (in particular to the abovementioned domains) is still in its infancy and the impact of HL on self-management (via a key informant lens) has yet to be studied. Objectives: The main aim in this thesis was to incorporate both sides of the HL equation (patients and key informants) into investigating the role of HL in chronic respiratory disease management. This led to two objectives: 1) To identify HL tools used in asthma and/or chronic obstructive pulmonary disease (COPD) management and examine their characteristics; and 2) To assess key informants’ perspectives re barriers to asthma/COPD self-management and the solutions to address such challenges. Methods: A systematic review was undertaken to review the literature on HL tools that assessed any of the five domains on asthma/COPD patients. Following this, a qualitative study was conducted with national and international key informants (e.g., health care professionals (HCPs), researchers, and policymakers) who were involved in the care of asthma/COPD patients to determine perceived patient barriers to competent self-management and the possible solutions to overcome these barriers. Results: The review identified 65 tools with a majority assessing ‘understanding’ and a minority on ‘communication’. Only two tools assessed all five domains and less than half had been validated. Thematic analysis of the 45 interviews resulted in seven barriers surrounding the themes of time, information overload, and jargon and six solutions focusing on tailored education, better communication, and building relationships. Conclusions: Self-management is a combined effort achieved only through the engagement of patients, HCPs, and the system. Both studies showed shortcomings in the ‘communication’ domain, possibly due to the complex phenomenon of communication requiring at least two individuals in the process. These findings suggest that HL researchers and health care programs should recommend new strategies for chronic respiratory disease management with a specific emphasis on the concept of ‘communication’.
Forward production of beauty baryons in pp collisions at LHC
Creators: name: Bednyakov, V. A.
name: Lykasov, G. I.
name: Lyubushkin, V. V.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The production of charmed and beauty baryons in proton-proton collisions at high energies is analyzed within the modified quark-gluon string model. We present some predictions for the experiments on the forward beauty baryon production in pp collisions at LHC energies. This analysis allows us to find useful information on the Regge trajectories of the heavy (b barb) mesons and the sea beauty quark distributions in the proton.
description: 14 pages, 12 figures
title: Proxy Advisors
Creators: name: Larcker, David F.
name: Tayan, Brian
Publisher: name: Corporate Governance Research Initiative
Year: 2017

description: This Research Spotlight provides a summary of the academic literature on the role of proxy advisors in the proxy voting process: The influence of proxy advisors on director elections, the influence of proxy advisors on say on pay, the influence of proxy advisors on proxy contests, and the influence of proxy advisors on compensation design. This Research Spotlight expands upon issues introduced in the Quick Guide “Investors and Activism”.
Global Saturation of Regularization Methods for Inverse Ill-Posed Problems
Creators: name: Herdman, Terry
name: Spies, Ruben D.
name: Temperini, Karina G.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 47A52, 65J20

description: In this article the concept of saturation of an arbitrary regularization method is formalized based upon the original idea of saturation for spectral regularization methods introduced by A. Neubauer in 1994. Necessary and sufficient conditions for a regularization method to have global saturation are provided. It is shown that for a method to have global saturation the total error must be optimal in two senses, namely as optimal order of convergence over a certain set which at the same time, must be optimal (in a very precise sense) with respect to the error. Finally, two converse results are proved and the theory is applied to find sufficient conditions which ensure the existence of global saturation for spectral methods with classical qualification of finite positive order and for methods with maximal qualification. Finally, several examples of regularization methods possessing global saturation are shown.
description: 29 pages
A Polyaniline with Near-Infrared Optical Response to Saccharides
Creators: name: Pringsheim, Erika
name: Terpetschnig, Ewald
name: Piletsky, Sergey A.
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: 540 Chemie

description: A sugar-binding polymer film capable of continuous sensingarises from the copolymerization of aniline and 3-aminophenylboronic acid. Its absorption spectrum between 500 and 800 nm undergoes large changes on addition of various saccharides at neutral pH, changes which are dependent on the saccharide concentration and are fully reversible. These films represent an interesting alternative to enzyme-based glucose sensors because of their ease of preparation, compatibility with LED and diode laser light sources, and their thermal and temporal stability.
Domain formation in membranes with quenched protein obstacles: Lateral heterogeneity and the connection to universality classes
Creators: name: Fischer, T.
name: Vink, R. L. C.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We show that lateral fluidity in membranes containing quenched protein obstacles belongs to the universality class of the two-dimensional random-field Ising model. The main feature of this class is the absence of a phase transition: there is no critical point, and macroscopic domain formation does not occur. Instead, there is only one phase. This phase is highly heterogeneous, with a structure consisting of micro-domains. The presence of quenched protein obstacles thus provides a mechanism to stabilize lipid rafts in equilibrium. Crucial for two-dimensional random-field Ising universality is that the obstacles are randomly distributed, and have a preferred affinity to one of the lipid species. When these conditions are not met, standard Ising or diluted Ising universality apply. In these cases, a critical point does exist, marking the onset toward macroscopic demixing.
description: 10 pages, 10 figures
New polar plasticizers for luminescence-based sensors
Creators: name: Papkovsky, Dmitri B.
name: Mohr, Gerhard J.
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1997
Subjects: subject: Sensors; Optical sensor; Plasticizer; Luminescence; Quenching
subject: 540 Chemie

description: The widely used polar plasticizer 2-nitrophenyl octyl ether (NPOE) is found to act as a dynamic quencher of the luminescence of certain indicators; quenching studies have been performed both in solution and sensor membranes plasticized with NPOE. A series of 2-cyanophenyl alkyl ethers (with C8, C10 and C12 alkyl chains) has been prepared and is found not to act as quenchers and hence, represent an improved class of plasticizers for use in luminescence-based sensors.
Production of excited double hypernuclei via Fermi breakup of excited strange systems
Creators: name: Lorente, Alicia Sanchez
name: Botvina, Alexander
name: Pochodzalla, Josef
Publisher: name: arXiv
Year: 2011
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Precise spectroscopy of multi-strange hypernuclei provides a unique chance to explore the hyperon-hyperon interaction. In the present work we explore the production of excited states in double hypernuclei following the micro-canonical break-up of an initially excited double hypernucleus which is created by the absorption and conversion of a stopped $Ξ^{-}$ hyperon. Rather independent on the spectrum of possible excited states in the produced double hypernuclei the formation of excited states dominates in our model. For different initial target nuclei which absorb the $Ξ^-$, different double hypernuclei nuclei dominate. Thus the ability to assign the various observable $γ$-transitions in a unique way to a specific double hypernuclei by exploring various light targets as proposed by the {\Panda} collaboration seems possible. We also confront our predictions with the correlated pion spectra measured by the E906 collaboration.
description: accepted in Physics Letters B
Practical mergers : export-oriented value chains and food sovereignty pathways in Haiti and Ecuador
Creators: name: Hergesheimer, Chris
Publisher: name: University of British Columbia
Year: 2017

description: This dissertation explores the possibilities and limitations of food sovereign agricultural value chains and the role that alternative trading arrangements, including export-oriented fair trade, can play in their development. The dissertation first develops value chain evaluation criteria from the conceptual congruence between the principles of food sovereignty and fair trade. This framework identifies six criteria that contribute to a ‘practical merger’, which is defined as an export-oriented value chain that aligns closely with food sovereignty principles. Utilizing a comparative case study methodology with a small-scale fair trade mango grower association in Haiti and a small-scale fair trade banana producer association in Ecuador, this dissertation analyzes the diverse processes and mechanisms that smallholders and their associations use to take advantage of the benefits, and mitigate the risks, of participation in fair trade export markets. It examines the following questions: What core principles of food sovereignty can be practically merged with market-based development agendas to create more equitable export-oriented value chains for small-scale producers? How can the practical merger framework contribute to understanding the relationships between participation in fair trade supply chains and food sovereignty principles? My case studies show that small-scale producers desire and rely on participation in international markets, but experience challenges related to farm size and economies of scale, the lack of participation in value chain governance, and value distribution asymmetries throughout the supply chains. Results also highlight additional limitations to small-scale producers’ abilities to shape export-oriented value chains in their favor. In Haiti, technical and structural challenges (such as access to transportation infrastructure, credit, and processing facilities) and relational challenges (reliance on a single buyer/exporter, and market competition from international value chain interventions) present obstacles to the realization of a practical merger. In Ecuador, barriers to this realization include producer/associations’ inability to influence the locus of value creation, as well as challenges around influencing policy and value chain governance beyond the local/regional level. This dissertation concludes by elaborating on the conditions necessary for export-oriented value chains to achieve a practical merger and the types of food system transformations that practical mergers in export oriented value chains can stimulate.
Optical sensing of pH based on polypyrrole films
Creators: name: de Marcos, Susana
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1996
Subjects: subject: Optical sensors; Sensors; Polypyrrole; Infrared spectrometry
subject: 540 Chemie

description: An optical sensor for pH is presented which is based on the use of a thin polypyrrole (PPy) film obtained by chemical oxidation of pyrrole and deposited as a < 1 μm film on the walls of a polystyrene cuvette. The spectrum of PPy displays strong absorption in the near infrared at around 900 nm, and a characteristic minimum at around 550 nm. The shape and intensity of the spectrum are pH-dependent between pH 6 and 12, the minimum being shifted to shorter wavelengths at higher pH, and the absorbance of the longwave band increasing in the range 600–900 nm range. The apparent pKa is around 8.6, but once exposed to a pH 6, the films need to be reconditioned with 0.1 M HCl in order to give the same response to pH. The films are an interesting alternative to indicator-based pH sensor films in that they do not require a dye to be immobilized, are fully compatible with LED and diode laser light sources, and can easily be prepared.
Complete classification of torsion of elliptic curves over quadratic cyclotomic fields
Creators: name: Najman, Filip
Publisher: name: arXiv
Year: 2010
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: In a previous paper, the author examined the possible torsions of an elliptic curve over the quadratic fields $\mathbb Q(i)$ and $\mathbb Q(\sqrt{-3})$. Although all the possible torsions were found if the elliptic curve has rational coefficients, we were unable to eliminate some possibilities for the torsion if the elliptic curve has coefficients that are not rational. In this note, by finding all the points of two hyperelliptic curves over $\mathbb Q(i)$ and $\mathbb Q(\sqrt{-3})$, we solve this problem completely and thus obtain a classification of all possible torsions of elliptic curves over $\mathbb Q(i)$ and $\mathbb Q(\sqrt{-3})$.
description: 6 pages, to appear in J. Number Theory
Long-lifetime based pH micro-optodes without oxygen interference
Creators: name: Kosch, Ute
name: Klimant, Ingo
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1999
Subjects: subject: 540 Chemie

description: The first decay time-based fiber optic pH microsensors are presented which are without cross-sensitivity to molecular oxygen. They are based on radiationless energy transfer from the donor ruthenium(II)-tris(1,10-phenanthroline) to a pH-sensitive sulfonephthalein acceptor dye. The microsensors have decay times in the microsecond range, a fact that makes them compatible with existing devices designed for optical oxygen microsensing. The sensor tips have diameters of 20 to 30 μm. Outstanding features are the excellent mechanical stability and the inertness to quenching by oxygen. The dynamic range depends on the pKa of the selected pH indicator. The sensors were characterized with respect to the dynamic range, response, storage stability and photostability. A high resolution pH measurement in a marine sediment core serves as an example for its utility.
Hydrophilic sensor membrane based on cation-selective protic chromoionophore
Creators: name: Krause, Christian
name: Werner, Tobias
name: Huber, Christian
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 2000
Subjects: subject: 540 Chemie

description: The first potassium optode based on a protic chromoionophore immobilized in a hydrogel matrix is presented. The highly selective protic chromoionophore consists of a cryptohemispherand moiety and a trinitroanilino chromophore part. The acidifying power of potassium ions over sodium ions is 0.6 pH units. This correlates with the findings in solution. In contrast to several crown and aza-crown based chromophores the highly pre-organized moiety allows ion detection even in aqueous environment. The detection limit for potassium ions at ¶pH 7.7 is 5 μM.
title: Managers, work and ideology
Creators: name: Jones, G. L
Publisher: name: University of Kent
Year: 1988

description: This thesis is concerned with developing and contributing to the sociological study of managers and management. More specifically, it considers the relationships between processes conferring occupational identity, with managerial ideology and the social organisation of managerial work. It asks how people come to see themselves as managers in the context of social and organisational change. Central to this process of developing a managerial identity are the sets of ideas managers draw upon to legitimise their own position in organisations and the division of labour generally. This process is explored through the examination of a management training and development course designed for middle managers. It is argued that this course is essentially concerned with the confirmation of managerial identity. In this sense it approximates to a rite of passage. This process of creating an occupational identity as a manager takes place against a background of social, technical and organisational change which threatens important elements of the employment relation of middle managers. These changes are examined, as are the range of response managers may make to them. Finally, it is suggested that on the basis of the empirical material presented we may need to reconsider the location of managers in recent reformulations of service class theory
Kinematic Diffraction from a Mathematical Viewpoint
Creators: name: Baake, Michael
name: Grimm, Uwe
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences
subject: 78A45, 52C23, 42B10

description: Mathematical diffraction theory is concerned with the analysis of the diffraction image of a given structure and the corresponding inverse problem of structure determination. In recent years, the understanding of systems with continuous and mixed spectra has improved considerably. Simultaneously, their relevance has grown in practice as well. In this context, the phenomenon of homometry shows various unexpected new facets. This is particularly so for systems with stochastic components. After the introduction to the mathematical tools, we briefly discuss pure point spectra, based on the Poisson summation formula for lattice Dirac combs. This provides an elegant approach to the diffraction formulas of infinite crystals and quasicrystals. We continue by considering classic deterministic examples with singular or absolutely continuous diffraction spectra. In particular, we recall an isospectral family of structures with continuously varying entropy. We close with a summary of more recent results on the diffraction of dynamical systems of algebraic or stochastic origin.
description: 30 pages, invited review
The difficulty of steering settlement development to reduce the loss of ecosystem services: an exploration of different development scenarios in Switzerland using spatially explicit land-use models
Creators: name: Schwaab, Jonas
name: Lautenbach, Sven
name: Braun-Dubler, Nils
name: Gmünder, Markus
name: Grêt-Regamey, Adrienne
name: Van Strien, Maarten J.
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Medicine
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Science Policy

description: To reduce the negative environmental impact of settlement development, a range of policy instruments are available. Empirical studies have highlighted advantages and disadvantages of different instruments, including tradable development rights (TDRs) and zoning. We add to this knowledge by developing a land-use modelling framework that can be used to assess the potential impact of different policy scenarios on the spatial pattern of settlement development and the potential loss of ecosystem services. We compare the impact of four scenarios that are inspired by different policy instruments. Our results show that limiting the urban growth in certain municipalities or regions has a high impact on ecosystem services. Thus, the definition of sending and receiving areas as employed in TDR programs could be very useful. However, possible trade-offs will have to be taken into consideration, in particular between the protection of fertile agricultural soils and the protection of valuable nature areas.
Performance Analysis of Contention Window Cheating Misbehaviors in Mobile Ad Hoc Networks
Creators: name: Kalaiarasi, R.
name: Sara, Getsy S.
name: Pari, S. Neelavathy
name: Sridharan, D.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: Mobile Ad Hoc Network (MANET) is a collection of nodes that can be rapidly deployed as a multi-hop network without the aid of any centralized administration. Misbehavior is challenged by bandwidth and energy efficient medium access control and fair share of throughput. Node misbehavior plays an important role in MANET. In this survey, few of the contention window misbehavior is reviewed and compared. The contention window cheating either minimizes the active communication of the network or reduces bandwidth utilization of a particular node. The classification presented is in no case unique but summarizes the chief characteristics of many published proposals for contention window cheating. After getting insight into the different contention window misbehavior, few of the enhancements that can be done to improve the existing contention window are suggested. The purpose of this paper is to facilitate the research efforts in combining the existing solutions to offer more efficient methods to reduce contention window cheating mechanisms.
description: 12 pages,4 figures, 1 table
The ordered phase of the one-dimensional Ising spin glass with long-range interactions
Creators: name: Moore, M. A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The one-dimensional long-range Ising spin glass provides useful insights into the properties of finite dimensional spin glasses with short-range interactions. The defect energy renormalization group equations derived for it by Kotliar, Anderson and Stein have been re-examined and a new fixed point has been found. The fixed points which have previously been studied are found to be inappropriate. It is shown that the renormalization group equations themselves directly imply that the spin glass phase is replica symmetric, in agreement with droplet model expectations, when the range exponent $σ$ lies between the upper and lower critical values.
description: 9 pages, no figures.
Novel optical sensor materials based on solubilization of polar dyes in apolar polymers
Creators: name: Mohr, Gerhard J.
name: Werner, Tobias
name: Oehme, Ines
name: Preininger, Claudia
name: Klimant, Ingo
name: Kovacs, Barna
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1997
Subjects: subject: 540 Chemie

description: Homogenous and fully transparent optical sensor layers have been prepared by pairing anionic indicator dyes with lipophilic quaternary ammonium halides (see Figure for an example) and then dissolving the pairs in an appropriate polymer. The synthesis of six ion pairs and the characterization of the resulting materials are described, along with the mechanisms responsible fo detection of several gascous species and ions.
Anti-mirror effect: A perfect lens brings a brighter feature
Creators: name: Xu, Yadong
name: Du, Shengwang
name: Gao, Lei
name: Chen, Huanyang
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optics (physics.optics)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: In this letter, we show that a perfect lens can be employed to make multiple objects appear like only one in the far field, leading to a new concept of illusion optics. Numerical simulations are performed to verify the functionalities for both passive and active objects. The conceptual device can be utilized to enhance the illumination brightness for both incoherent and coherent systems.
description: 7 pages, 5 figures
CMB in a box: causal structure and the Fourier-Bessel expansion
Creators: name: Abramo, L. Raul
name: Reimberg, Paulo H.
name: Xavier, Henrique S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This paper makes two points. First, we show that the line-of-sight solution to cosmic microwave anisotropies in Fourier space, even though formally defined for arbitrarily large wavelengths, leads to position-space solutions which only depend on the sources of anisotropies inside the past light-cone of the observer. This happens order by order in a series expansion in powers of the visibility $γ=e^{-μ}$, where $μ$ is the optical depth to Thompson scattering. We show that the CMB anisotropies are regulated by spacetime window functions which have support only inside the past light-cone of the point of observation. Second, we show that the Fourier-Bessel expansion of the physical fields (including the temperature and polarization momenta) is an alternative to the usual Fourier basis as a framework to compute the anisotropies. In that expansion, for each multipole $l$ there is a discrete tower of momenta $k_{i,l}$ (not a continuum) which can affect physical observables, with the smallest momenta being $k_{1,l} ~ l$. The Fourier-Bessel modes take into account precisely the information from the sources of anisotropies that propagates from the initial value surface to the point of observation - no more, no less. We also show that the physical observables (the temperature and polarization maps), and hence the angular power spectra, are unaffected by that choice of basis. This implies that the Fourier-Bessel expansion is the optimal scheme with which one can compute CMB anisotropies. (Abridged)
description: 23 pages, 7 figures
The 2008 Outburst in the Young Stellar System Z CMa: The First Detection of Twin Jets
Creators: name: Whelan, Emma
name: Dougados, Catherine
name: Perrin, Marshall
name: Bonnefoy, Mickael
name: Bains, Indra
name: Redman, Matt
name: Ray, Tom
name: Bouy, Herve
name: Benisty, Myriam
name: Bouvier, Jerome
name: Chauvin, Gael
name: Garcia, Paulo
name: Grankin, Konstantin
name: Malbet, Fabien
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The Z CMa binary is understood to undergo both FU Orionis (FUOR) and EX Orionis (EXOR) type outbursts. While the SE component has been spectro- scopically identified as an FUOR, the NW component, a Herbig Be star, is the source of the EXOR outbursts. The system has been identified as the source of a large outflow, however, previous studies have failed to identify the driver. Here we present adaptive optics (AO) assisted [FeII] spectro-images which reveal for the first time the presence of two jets. Observations made using OSIRIS at the Keck Observatory show the Herbig Be star to be the source of the parsec-scale outflow, which within 2'' of the source shows signs of wiggling and the FUOR to '' be driving a ~ 0.4 jet. The wiggling of the Herbig Be star's jet is evidence for an additional companion which could in fact be generating the EXOR outbursts, the last of which began in 2008 (Grankin & Artemenko 2009). Indeed the dy- namical scale of the wiggling corresponds to a time-scale of 4-8 years which is in agreement with the time-scale of these outbursts. The spectro-images also show a bow-shock shaped feature and possible associated knots. The origin of this structure is as of yet unclear. Finally interesting low velocity structure is also observed. One possibility is that it originates in a wide-angle outflow launched from a circumbinary disk.
description: accepted by ApJ letters
Bottom up approach to quantum gravity
Creators: name: Alvarez, Enrique
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A general introduction is given to what can be predicated about quantum gravity once the lessons from the standard model of particle physics are taken into account. In particular, the effective lagrangian point of view is briefly commented upon .
description: Contribution to ERE2010 (Granada, Spain)
Algal-herbivore interactions in a high carbon world : direct and indirect effects through individuals, populations, and communities
Creators: name: Anderson, Kathryn Michele
Publisher: name: University of British Columbia
Year: 2017

description: Consumer-resource interactions play an important role in determining the structure and function of ecological communities. Thus, herbivores may buffer or magnify the impacts of environmental change. In this thesis, I examine the ways in which herbivory mediates the effects of one of the most important facets of environmental change in marine ecosystems: ocean acidification (OA). Responses to OA by invertebrate herbivores are wide ranging, typically negative, and depend on species traits (e.g. reliance on calcification), population dynamics, and shifts in interspecific interactions. My goal was to conduct research across levels of biological organization to better understand the main pathways by which OA and associated increases in carbon dioxide (CO₂) will drive ecological change in herbivore-dominated systems. In Chapter 2, I examine the effect of CO₂ on herbivore growth and size-specific changes in feeding rate. I found that CO₂ had no impact on the size-specific feeding rates of the four-herbivore species I examined. However, changes in growth and body size in response to increased CO₂ may drive an overall reduction in the feeding rates of highly-calcified herbivores (e.g. urchins and gastropods), but not less calcified, crustacean herbivores. In Chapter 3, I used amphipod herbivores with short generation times to test the effects of CO₂ on per capita and abundance driven changes in herbivory. Again, I found no evidence for per capita changes in herbivory rate of this less calcified species, however increases in amphipod abundance lead to an increase in total herbivory. Finally, In Chapter 4, I manipulated both the abundance of gastropod herbivores and CO₂ in experimental tidepool communities in situ. I found that the indirect effects of CO₂ via the reduction of calcified herbivore pressure had a larger impact on tidepool community than CO₂ had directly. These results show that changes in herbivore pressure in response to OA will be driven primarily through changes in individual body size and herbivore abundance. Further, these changes in herbivory pressure can be more important in determining community structure under conditions of high CO₂ than other species-specific responses.
Fluorescent potential-sensitive dyes for use in solid state sensors for potassium ion
Creators: name: Murkovic, Ivana
name: Lobnik, Aleksandra
name: Mohr, Gerhard J.
name: Wolfbeis, Otto S.
Publisher: name: Universität Regensburg
Year: 1996
Subjects: subject: Sensors; PVC membranes; Polarity probes; Carbocyanines
subject: 540 Chemie

description: Fluorescent potential-sensitive dyes (PSDs) were screened for use in potassium-sensitive optical sensor membranes. A potassium-sensitive plasticized PVC layer containing valinomycin as an ion carrier, lipophilic borate salt as an anionic additive, and a PSD was chosen as a model for evaluating the applicability of PSDs. A commercial carbocyanine dye (3,3′-dihexadecyloxacarbocyanine perchlorate) was found to exhibit the best properties in terms of signal changes, photostability and operational life-time. The sensor membrane responds reversibly to potassium ion, with fluorescence intensity changes exceeding 50% and response times being of the order of 1 min. The response to potassium is slightly pH dependent. Typically, an 8% change in intensity is observed over the range pH 5–8. The new sensor membrane exhibits significantly improved signal changes compared to previous optodes based on related sensing schemes. We also report the effects of different plasticizers and lipophilic additives on the response of the layers. The response mechanism is discussed with respect to morphology of the membrane.