Correspondence Letter
In: The annals of occupational hygiene: an international journal published for the British Occupational Hygiene Society, Band 45, Heft 4, S. 336-338
ISSN: 1475-3162
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In: The annals of occupational hygiene: an international journal published for the British Occupational Hygiene Society, Band 45, Heft 4, S. 336-338
ISSN: 1475-3162
In: The annals of occupational hygiene: an international journal published for the British Occupational Hygiene Society, Band 44, Heft 8, S. 565-601
ISSN: 1475-3162
In: Springer eBook Collection
1. Macroscopic Theory -- 1.1 Electromagnetic field in a solid -- 1.2 Dielectric constant and optical conductivity -- 1.3 Crystal symmetry -- 1.4 Propagation of waves -- 1.5 Kramers-Krönig relations -- 1.6 The sum rule -- 1.7 Dispersion theory of classical oscillators -- 2. Crystal Lattice Absorption -- 2.1 Vibrational modes of a crystal lattice -- 2.2 Photon-phonon interaction -- 2.3 Microscopic theory of infra-red dispersion -- 2.4 Two-phonon absorption -- 3. Interband Transitions -- 3.1 Electron energy bands -- 3.2 Direct transitions -- 3.3 Critical points -- 3.4 Absorption band edges -- 3.5 Indirect transitions -- 3.6 Infra-red absorption in superconductors -- 4. Free Carrier Absorption -- 4.1 Classical theory -- 4.2 Intraband transitions -- 4.3 Electron transport -- 4.4 Surface admittance -- 4.5 Infra-red absorption in metals -- 4.6 Free carrier absorption in semiconductors -- 5. Plasma Effects -- 5.1 Free electron model -- 5.2 Volume plasmons -- 5.3 Surface plasmons -- 6. Exciton Effects -- 6.1 Electron-hole interaction -- 6.2 Optical absorption -- 6.3 Inert-atom solids and alkali halides -- 6.4 Semiconductors -- 6.5 Spatial dispersion -- 7. Non-Linear Optics -- 7.1 Classification of non-linear effects -- 7.2 Non-linear susceptibilities -- 7.3 Second harmonic generation -- 7.4 Parametric amplification and oscillation -- 7.5 Third order effects -- References.
In: Center for Migration Studies special issues, Band 3, Heft 1, S. 89-102
ISSN: 2050-411X
In: Review of social economy: the journal for the Association for Social Economics, Band 30, Heft 2, S. 257-262
ISSN: 1470-1162
Cover -- Contents -- Preface -- List of Cases -- List of Statutes -- List of Abbreviations -- 1 The criminal justice system and miscarriages of justice in England and Wales -- 2 Policing on the Ground: gathering evidence -- 3 The suspect at the police station -- 4 Remedies for police misconduct -- 5 The right to silence -- 6 Prosecution, bail and trial venue -- 7 Disclosure and sentence discounts -- 8 The trial -- 9 The appellate system and miscarriages of justice -- 10 Concluding comments -- Notes and References -- Bibliography -- Index.
Throughout the 1970s and 1980s, Canada studied the impact of its cabotage legislation thoroughly and opted to provide protection of the domestic shipping market with new legislation in 1992. This paper traces the decision-making process through this period, and the concurrent discussions within NAFTA under negotiations for liberalization of trade in services. Now that Canada has 13 years experience with the existing cabotage legislation, and has adopted a policy to promote the development of short sea shipping, this paper evaluates Canada's shipping policy options in order to identify if changes are required given the new policy environment.
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In: Computers and Electronics in Agriculture, Band 74, Heft 1, S. 129-136
In: Computers and Electronics in Agriculture, Band 42, Heft 2, S. 67-86
We measure the 10 and 18 μm silicate features in a sample of 67 local (z 0.28, 10 objects). We carry out a detailed modeling of the infrared spectrometer/Spitzer spectra by comparing several models that assume different geometries and dust composition: a smooth torus model, two clumpy torus models, a two-phase medium torus model, and a disk+outflow clumpy model. We find that the silicate features are well modeled by the clumpy model of Nenkova et al., and among all models, those including outflows and complex dust composition are the best. We note that even in AGN-dominated galaxies, it is usually necessary to add stellar contributions to reproduce the emission at the shortest wavelengths. ; With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)
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Context. Investigating the magnetic field structure in the innermost regions of relativistic jets is fundamental to understanding the crucial physical processes giving rise to jet formation, as well as to their extraordinary radiation output up to γ-ray energies. Aims. We study the magnetic field structure of the quasar CTA 102 with 3 and 7 mm VLBI polarimetric observations, reaching an unprecedented resolution (∼50 μas). We also investigate the variability and physical processes occurring in the source during the observing period, which coincides with a very active state of the source over the entire electromagnetic spectrum. Methods. We perform the Faraday rotation analysis using 3 and 7 mm data and we compare the obtained rotation measure (RM) map with the polarization evolution in 7 mm VLBA images. We study the kinematics and variability at 7 mm and infer the physical parameters associated with variability. From the analysis of γ-ray and X-ray data, we compute a minimum Doppler factor value required to explain the observed high-energy emission. Results. Faraday rotation analysis shows a gradient in RM with a maximum value of ∼6 × 10 4 rad m -2 and intrinsic electric vector position angles (EVPAs) oriented around the centroid of the core, suggesting the presence of large-scale helical magnetic fields. Such a magnetic field structure is also visible in 7 mm images when a new superluminal component is crossing the core region. The 7 mm EVPA orientation is different when the component is exiting the core or crossing a stationary feature at ∼0.1 mas. The interaction between the superluminal component and a recollimation shock at ∼0.1 mas could have triggered the multi-wavelength flares. The variability Doppler factor associated with such an interaction is large enough to explain the high-energy emission and the remarkable optical flare occurred very close in time. © ESO 2019. ; DB acknowledges support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme under grant agreement No 771282. IA acknowledges support by a Ramon y Cajal grant of the Ministerio de Ciencia, Innovacion y Universidades (MICINU) of Spain. The research at the IAA-CSIC was supported in part by the MICINU through grant AYA2016-80889-P. ; Peer Reviewed
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Funding Information: Acknowledgements. We thank Eduardo Ros for the valuable suggestions that helped improve this manuscript. This research has been consulting data from the MOJAVE database that is maintained by the MOJAVE team (Lister et al. 2009). C. Casadio acknowledges support from the European Research Council (ERC) under the European Union Horizon 2020 research and innovation programme under the grant agreement No. 771282. The research at Boston University was supported by NASA through Fermi Guest Investigator program grants NNX17K0649 an 80NSSC20K1567. This research has made use of data obtained with the Global Millimeter VLBI Array (GMVA), which consists of telescopes operated by the MPIfR, IRAM, Onsala, Metsahovi, Yebes, the Korean VLBI Network, the Greenland Telescope, the Green Bank Observatory and the Very Long Baseline Array (VLBA). The VLBA is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The data were correlated at the correlator of the MPIfR in Bonn, Germany. We thank W. Alef, A. Bertarini, H. Rottmann and I. Wagner for their support at the MPIfR VLBI correlator. We also thank Pablo Torne for his help at the IRAM 30m telescope. Publisher Copyright: © ESO 2021. ; Context. Controversial studies on the jet collimation profile of BL Lacertae (BL Lac), the eponymous blazar of the BL Lac objects class, complicate the scenario in this already puzzling class of objects. Understanding the jet geometry in connection with the jet kinematics and the physical conditions in the surrounding medium is fundamental for better constraining the formation, acceleration, and collimation mechanisms in extragalactic jets. Aims. With the aim of investigating the jet geometry in the innermost regions of the BL Lac jet, and resolving the controversy, we explore the radio jet in this source using high-resolution millimeter-wave VLBI data. Methods. We collect 86 GHz GMVA and 43 GHz VLBA data to obtain stacked images that we use to infer the jet collimation profile by means of two comparable methods. We analyze the kinematics at 86 GHz, and we discuss it in the context of the jet expansion. Finally, we consider a possible implication of the Bondi sphere in shaping the jet of BL Lac. Results. The jet in BL Lac expands with an overall conical geometry. A higher expanding rate region is observed between ∼5 and 10 pc (de-projected) from the black hole. Such a region is associated with the decrease in brightness usually observed in high-frequency VLBI images of BL Lac. The jet retrieves the original jet expansion around 17 pc, where the presence of a recollimation shock is supported by both the jet profile and the 15 GHz kinematics (MOJAVE survey). The change in the jet expansion profile occurring at ∼5 pc could be associated with a change in the external pressure at the location of the Bondi radius (∼3.3 × 105RS). ; Peer reviewed
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The classic papers that laid the foundations of modern ecology alongside commentaries by noted ecologists. The period of 1970 to 1995 was a time of tremendous change in all areas of ecology—from an increased rigor for experimental design and analysis to the reevaluation of paradigms, new models for understanding, and theoretical advances. Edited by ecologists Thomas E. Miller and Joseph Travis, Foundations of Ecology II includes facsimiles of forty-six papers from this period alongside expert commentaries that discuss a total of fifty-three key studies, addressing topics of diversity, predation, complexity, competition, coexistence, extinction, productivity, resources, distribution, abundance, and conservation. The result is more than a catalog of historic firsts; this book offers diverse perspectives on the foundational papers that led to today's ecological work. Like this book's 1991 predecessor, Foundations of Ecology edited by Leslie A. Real and James H. Brown, Foundations of Ecology II promises to be the essential primer for graduate students and practicing ecologists for decades to come