2,138 research outputs found
Complete Decoupling Limit of Ghost-free Massive Gravity
We present the complete form of the decoupling limit of ghost-free massive
gravity with a Minkowski reference metric, including the full interactions of
the helicity-1 and helicity-0 modes of the massive spin-2 field. While in the
metric language the square root structure of the mass terms makes it difficult
to find a simple way to write down the interactions, we show that using the
vierbein formulation of massive gravity, including Stueckelberg fields for both
diffeomorphism and local Lorentz symmetries, we can find an explicitly resummed
expression for the helicity-1 field interactions. We clarify the equations of
motion for the Lorentz Stueckelberg fields and how these generate the symmetric
vierbein condition which guarantees equivalence between the vierbein and metric
formulations of massive gravity.Comment: 20 pages, typos corrected, references adde
Seamless Electricity Trade between Canada and US Northeast
We analyse how the wholesale electricity market deregulation could modify exchanges between three Canadian regions (Ontario, Quebec and New Brunswick) and two U.S. regions (New York and New England), which were already trading electricity before the regulatory change took place in 1997. We find that the pre-1997 exchanges already made possible fuel cost savings of 358.7 million. Canadian regions are the main beneficiaries under the assumption that exports are priced at the marginal costs of the importing regions. Imports from the Canadian regions, although significant, are not large enough to lower the marginal costs of the U.S. regions. Hence electricity deregulation across the border should not significantly decrease prices in the U.S. regions although the latter are becoming more dependant upon imports from Canada. Greenhouse gas emissions increase by 4.3 Mt CO2 eq. in the wake of the open wholesale electricity market because of the low cost of coal, particularly in Ontario. Environmental concerns and the limited availability of additional hydroelectric power in Canada could change the trade patterns as electricity demand continue to grow.Minimum Electricity, deregulation, trade
Seamless Electricity Trade between Canada and US Northeast
We analyse how the wholesale electricity market deregulation could modify exchanges between three Canadian regions (Ontario, Quebec and New Brunswick) and two U.S. regions (New York and New England), which were already trading electricity before the regulatory change took place in 1997. We find that the pre-1997 exchanges already made possible fuel cost savings of 358.7 million. Canadian regions are the main beneficiaries under the assumption that exports are priced at the marginal costs of the importing regions. Imports from the Canadian regions, although significant, are not large enough to lower the marginal costs of the U.S. regions. Hence electricity deregulation across the border should not significantly decrease prices in the U.S. regions although the latter are becoming more dependant upon imports from Canada. Greenhouse gas emissions increase by 4.3 Mt CO2 eq. in the wake of the open wholesale electricity market because of the low cost of coal, particularly in Ontario. Environmental concerns and the limited availability of additional hydroelectric power in Canada could change the trade patterns as electricity demand continue to grow.Electricity, deregulation, trade
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Movements Mimicking Myoclonus Associated with Spinal Cord Pathology: Is This a "Pure Motor Restless Legs Syndrome"?
Background: The neuroanatomic substrate of restless legs syndrome (RLS) is poorly understood, and the diagnosis is clinically made based upon subjective sensory symptoms, although a motor component is usually present. Case Report: We report two cases of elderly patients with spinal pathology who were referred by neurologists for myoclonus. Both had semi-rhythmic leg movements that partially improved while standing, but denied any urge to move. These movements improved dramatically with pramipexole, a dopamine agonist used for RLS. Discussion: We propose that this "myoclonus" is actually the isolated stereotypic motor component of RLS
Individual Professional Practice in the Company
Import 23/08/2017Táto bakalárska práca popisuje priebeh absolvovania individuálnej odbornej praxe v spoločnosti Kvados a.s.. Cieľom práce bol vývoj geoinformačného systému, pre poskytovanie máp a výpočet trás, s možnosťou rozšírenia o vlastné mapové vrstvy. V prvej časti popisujem fungovanie daného geoinformačného systému, spôsoby získania dát a úvodné nastavenia. V ďalšich kapitolách sa venujem implementácií samotného systému a android klienta, ktorý bude konzumovať vytvorené služby, s využitím open sourcových nástrojov.This bachelor thesis describes the process of absolving individual practical experience in the company Kvados a.s. The aim of the thesis was the development of the geoinformation system for providing maps and for calculation of routes with the possibility of extension for custom map layers. In the first chapter I describe the functioning of the geoinformation system, methods of obtaining data and initial settings. The following chapters deal with the implementation of the system itself and the Android client that will consume created services with usage of the open source tools.460 - Katedra informatikyvýborn
Review: Christian Intercultural Communication
A Review: Chang, C. Tim, and Ashley E. Chang. Christian Intercultural Communication: Sharing God’s Love with People of Other Cultures. Dubuque, IA: Kendall Hunt Publishing Company, 2021. 277 Pages. $82.11
De la révision du Dictionnaire de Samuel Galley
Le Dictionnaire fang–français et français–fang de Samuel Galley (1964) constitue une contribution importante dans l'histoire lexicographique du parler et, par sa nature biscopale, un intérêt pour les locuteurs du fang. Au demeurant, il présente un nombre important de lacunes qui méritent d'être corrigées. En l'occurrence, et entre autres, le lexicographe n'a pas mentionné les critères selon lesquels les items lexicaux ont été lemmatisés dans le dictionnaire. Par conséquent, on est forcé de deviner les sources du dictionnaire. Le traitement des mots composés et des homo-nymes doit également être amélioré. Ce sont ces améliorations que nous esquissons dans la pré-sente proposition.
Mots clés: dictionnaire, lexicographie, source, pré-textes, nomencla-ture, posttextes, signe, lemmes, biscopal, macrostructure, microstruc-ture, entête, paraphrase, mot composé, homonyme
Cobalt(II) Terpyridin-4′-yl Nitroxide Complex as an Exchange-Coupled Spin-Crossover Material
pin-crossover (SCO) was studied in [Co(L)2](CF3SO3)2, where L stands for diamagnetic 2,2′:6′,2′′-terpyridine (tpy) and its paramagnetic derivative, 4′-{4-tert-butyl(N-oxy)aminophenyl}-substituted tpy (tpyphNO). The X-ray crystallographic analysis clarified the Co-N bond length change (Δd) in high- and low-temperature structures; Δdcentral = 0.12 and Δddistal = 0.05 Å between 90 and 400 K for L = tpy and Δdcentral = 0.11 and Δddistal = 0.06 Å between 90 and 300 K for L = tpyphNO. The low- and high-temperature structures can be assigned to approximate low- and high-spin states, respectively. The magnetic susceptibility measurements revealed that the χmT value of [Co(tpyphNO)2](CF3SO3)2 had a bias from that of [Co(tpy)2](CF3SO3)2 by the contribution of the two radical spins. The tpy compound showed a gradual SCO around 260 K and on cooling the χmT value displayed a plateau down to 2 K. On the other hand, the tpyphNO compound showed a relatively abrupt SCO at ca. 140 K together with a second decrease of the χmT value on further cooling below ca. 20 K. From the second decrease, Co-nitroxide exchange coupling was characterized as antiferromagnetic with 2JCo-rad/kB = −3.00(6) K in the spin-Hamiltonian H = −2JCo-rad(SCo·Srad1 + SCo·Srad2). The magnetic moment apparently switches double-stepwise as 1 μB ⇄ 3 μB ⇄ 5 μB by temperature stimulus
Pedagogical practice and support of english language student teachers during the practicum in Kenya
This study is an analysis of pedagogical practice and support of English language student teachers during a practicum (teaching practice) in Kenya with a view to
discerning what they learnt and the issues that influenced such learning. The study was conducted against a background of calls for research that could provide information for reform of teacher education in general and English language teacher education (ELTE) in particular. The practicum is recognised as an important aspect of all professional learning and is part of most teacher education programmes all over the world. Yet, my literature review revealed that very little research exists in this area, more so in ELTE. Of the previous studies on teaching practice (TP), very
few are from developing countries and certainly none (that I know of) in Kenya.
This was an interpretive qualitative case study involving seventeen participants - six student teachers, six teacher educators and five cooperating teachers. Data was
generated through semi-structured interviews, observations and analysis of relevant documents. The findings generally show that the English language student teachers' practice was mainly focused on surviving the practicum and getting the desired grades to enable them graduate successfully. Consequently, though they learnt some procedural pedagogical knowledge, they were not supported to develop pedagogical reasoning, which is supposed to be the main goal of TP. Some of the issues that influenced teacher learning in this manner were: a weak link between coursework at university and practice in schools, the lack of a clear definition of the parameters of practice and inappropriate conceptualisation of support.
My study contributes to the field of ELTE by qualitatively analysing the experiences of all the key participants during one TP session and exploring the question of what
the student teachers actually learn during their placements, in a more holistic manner than has featured in most previous research on TP in the field. My study also
supports some earlier studies that had similar findings on some aspects of TP; for example, that student teacher learning is only effective during the practicum if there
is coordination between all the partners on ELTE. I believe the findings of my study are relevant to TP in other subjects in Kenya, and also other Anglophone African
countries where the system of the practicum is generally quite similar
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