5,983 research outputs found
Chuck for delicate drills
Development of oil film technique to couple power between drive spindle and drill chuck for delicate drilling operations is discussed. Oil film permits application of sufficient pressure, but stops rotating when drill jams. Illustration of equipment is provided
Fanny Copeland and the geographical imagination
Raised in Scotland, married and divorced in the English south, an adopted Slovene, Fanny Copeland (1872 â 1970) occupied the intersection of a number of complex spatial and temporal conjunctures. A Slavophile, she played a part in the formation of what subsequently became the Kingdom of Yugoslavia that emerged from the First World War. Living in Ljubljana, she facilitated the first âforeign visitâ (in 1932) of the newly formed Le Play Society (a precursor of the Institute of British Geographers) and guided its studies of SolÄava (a then âremoteâ Alpine valley system) which, led by Dudley Stamp and commended by Halford Mackinder, were subsequently hailed as a model for regional studies elsewhere. Arrested by the Gestapo and interned in Italy during the Second World War, she eventually returned to a socialist Yugoslavia, a celebrated figure. An accomplished musician, linguist, and mountaineer, she became an authority on (and populist for) the Julian Alps and was instrumental in the establishment of the Triglav National Park. Copelandâs role as participant observer (and protagonist) enriches our understanding of the particularities of her time and place and illuminates some inter-war relationships within G/geography, inside and outside the academy, suggesting their relative autonomy in the production of geographical knowledge
Correspondence between Jordan-Einstein frames and Palatini-metric formalisms
We discuss the conformal symmetry between Jordan and Einstein frames
considering their relations with the metric and Palatini formalisms for
modified gravity. Appropriate conformal transformations are taken into account
leading to the evident connection between the gravitational actions in the two
mentioned frames and the Hilbert-Einstein action with a cosmological constant.
We show that the apparent differences between Palatini and metric formalisms
strictly depend on the representation while the number of degrees of freedom is
preserved. This means that the dynamical content of both formalism is
identical.Comment: 6 pages, to appear in Mod. Phys. Lett.
From p-branes to Cosmology
We study the relationship between static p-brane solitons and cosmological
solutions of string theory or M-theory. We discuss two different ways in which
extremal p-branes can be generalised to non-extremal ones, and show how wide
classes of recently discussed cosmological models can be mapped into
non-extremal p-brane solutions of one of these two kinds. We also extend
previous discussions of cosmological solutions to include some that make use of
cosmological-type terms in the effective action that can arise from the
generalised dimensional reduction of string theory or M-theory.Comment: Latex, 24 pages, no figur
Art Therapy ethical practice and multicultural/diversity competence
The Conference proceedings' website is located at
http://www.xcdsystem.com/aata2013/proceedings/prof108.htmlTheme: Art Therapy: Connecting Visual Expression & HealingThe United States Census (2010) confirms a shift from a nation that is primarily White, from Western European backgrounds, to a country in which the majority of residents are from visible racial ethnic, and non-English speaking backgrounds (DâAndrea & Arrendondo, 2002). Consequently, this shift implies art therapists will be challenged to become expert in culturally congruent treatment. The American Art Therapy Associationâs Ethical Principles for Art Therapists (2011) Section 6.0 serves âŠpostprin
Central European foreign exchange markets: a cross-spectral analysis of the 2007 financial crisis
This paper investigates co-movements between currency markets of Czech Republic, Poland, Hungary, Slovakia and the Euro in the year following the drying up of money markets in August 2007. The paper shows that assessing the degree of foreign currency co-movement by correlation can lead to concluding, erroneously, that financial contagion has not occurred. Using cross-spectral methods, the paper shows that defining contagion as changes in the structure of co-movements of asset prices encompasses more of the complex nature of exchange rate dynamics. What is shown is that, following August 2007, there is increased in the intensity of co-movements, but non-linearly. Focusing on the activities of a mix of banks and currency managers, it is suggested that changes in the structure of currency interaction present an unfavourable view of the contagion experienced by at least three of these currencies
Vitellogenesis as a biomarker for estrogenic contamination of the aquatic environment
A rapidly increasing number of chemicals, or their degradation products, are being recognized as possessing estrogenic activity, albeit usually weak. We have found that effluent from sewage treatment works contains a chemical, or mixture of chemicals, that induces vitellogenin synthesis in male fish maintained in the effluent, thus indicating that the effluent is estrogenic. The effect was extremely pronounced and occurred at all sewage treatment works tested. The nature of the chemical or chemicals causing the effect is presently not known. However, we have tested a number of chemicals known to be estrogenic to mammals and have shown that they are also estrogenic to fish; that is, no species specificity was apparent. Many of these weakly estrogenic chemicals are known to be present in effluents. Further, a mixture of different estrogenic chemicals was considerably more potent than each of the chemicals when tested individually, suggesting that enhanced effects could occur when fish are exposed simultaneously to various estrogenic chemicals (as is likely to occur in rivers receiving effluent). Subsequent work should determine whether exposure to these chemicals at the concentrations present in the environment leads to any deleterious physiological effects
New synthetic cannabinoids and the potential for cardiac arrhythmia risk
Synthetic cannabinoid receptor agonists (SCRAs) have been associated with QT interval prolongation. Limited preclinical information on SCRA effects on cardiac electrogenesis results from the rapid emergence of new compounds and restricted research availability. We used two machine-learning-based tools to evaluate seven novel SCRAs' interaction potential with the hERG potassium channel, an important drug antitarget. Five SCRAs were predicted to have the ability to block the hERG channel by both prediction tools; ADB-FUBIATA was predicted to be a strong hERG blocker. ADB-5Br-INACA and ADB-4en-PINACA showed varied predictions. These findings highlight potentially proarrhythmic hERG block by novel SCRAs, necessitating detailed safety evaluations
A new view of k-essence
K-essence models, relying on scalar fields with non-canonical kinetic terms,
have been proposed as an alternative to quintessence in explaining the observed
acceleration of the Universe. We consider the use of field redefinitions to
cast k-essence in a more familiar form. While k-essence models cannot in
general be rewritten in the form of quintessence models, we show that in
certain dynamical regimes an equivalence can be made, which in particular can
shed light on the tracking behaviour of k-essence. In several cases, k-essence
cannot be observationally distinguished from quintessence using the homogeneous
evolution, though there may be small effects on the perturbation spectrum. We
make a detailed analysis of two k-essence models from the literature and
comment on the nature of the fine tuning arising in the models.Comment: 7 pages RevTeX4 file with four figures incorporate
Cosmic Strings, Zero Modes and SUSY breaking in Nonabelian N=1 Gauge Theories
We investigate the microphysics of cosmic strings in Nonabelian gauge
theories with N=1 supersymmetry. We give the vortex solutions in a specific
example and demonstrate that fermionic superconductivity arises because of the
couplings and interactions dictated by supersymmetry. We then use supersymmetry
transformations to obtain the relevant fermionic zero modes and investigate the
role of soft supersymmetry breaking on the existence and properties of the
superconducting strings.Comment: 12 pages, RevTex, submitted to Phys. Rev.
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