471 research outputs found
Database: THEMIS magnetopause crossings between 2007 and mid-2022
No full textDatabase of THEMIS observations of magnetopause crossings created for and used in:
Grimmich, N., Plaschke, F., Archer, M. O., Heyner, D., Mieth, J. Z. D., Nakamura, R., & Sibeck, D. G. (2023). Study of extreme magnetopause distortions under varying solar wind conditions.
Journal of Geophysical Research: Space Physics, 128, e2023JA031603. https://doi.org/10.1029/2023JA031603.
See section 3 of that publication for a detailed description of the identification process.
For further questions, please contact the corresponding author at [email protected]
Jak nudzić się umiejętnie? Refleksja na motywach myśli F. Nietschego, E. Ciorana, J. Brodskiego i M. Archer
No full textAccording to Nietzsche, boredom appeared already in Eden. By fighting it, man discovered the value of cognition. At the same time, however, he got into conflict with God. Nietzsche’s thought is continued by Cioran. He claims that the source of the essential boredom is man’s incompatibility with the world he lives in, and its effect is fear of himself. Boredom is paid for by man’s inability to find the ultimate meaning of the world and of life. Contrary to this unambiguously negative image of boredom, one can also point to its positive aspects. In his essay The Praise of Boredom, Brodsky advises to sometimes give in to boredom and use the experience to deepen one’s self-knowledge and to grasp the relation between consciousness and the dimension of time. The author of the text develops this idea. Using elements of the philosophical anthropology of critical realism M. Archer, he proposes an active and constructive approach to experiencing the state of boredom in the perspective of an affirmative and at the same time critical attitude towards oneself.Według Nietzschego nuda pojawiła się już w Raju, a walcząc z nią, człowiek odkrył wartość poznania, lecz równocześnie poróżnił się z Bogiem. Myśl Nietzschego kontynuuje Cioran, twierdząc, że źródłem pierwotnej nudy jest niedopasowanie człowieka do świata, w jakim żyje, a skutkiem – strach przed samym sobą. Nudą płaci człowiek za nieumiejętność odnalezienia ostatecznego sensu świata i życia. Wbrew temu jednoznacznie negatywnemu obrazowi nudy, można wskazać także pozytywne jej aspekty. Brodski w eseju Pochwała nudy radzi, by czasem poddać się nudzie i wykorzystać to doświadczenie dla pogłębienia samowiedzy i uchwycenia relacji między świadomością a wymiarem czasu. Autor tekstu rozwija tę ideę. Wykorzystując elementy antropologii filozoficznej realizmu krytycznego M. Archer, proponuje aktywne i konstruktywne podejście do przeżywania stanu znudzenia w perspektywie afirmatywnego, a zarazem krytycznego stosunku do samego siebie
Database: Cluster Magnetopause Crossings between 2001 and 2020
No full textDatabase of Cluster observations of magnetopause crossings created for and used in:
Grimmich, N., Plaschke, F., Grison, B., Prencipe, F., Escoubet, C. P., Archer, M. O., Constantinescu, O. D., Haaland, S., Nakamura, R., Sibeck, D. G., Darrouzet, F., Hayosh, M., and Maggiolo, R.: The Cluster spacecrafts' view of the motion of the high-latitude magnetopause, Ann. Geophys., 42, 371–394, https://doi.org/10.5194/angeo-42-371-2024, 2024. See section 2 and 3 of this publication for a detailed description of the identification and validation process.
For further questions, please contact the corresponding author at [email protected].
Please note that the preliminary GRMB data will be available here until the definitive GRMB dataset is available, and a link to the reference publication will be available on the Cluster Science Archive website https://csa.esac.esa.int/csa-web/, which will be used for long-term preservation of the GRMB data
Studies in the Orbweaving Spiders (Argiopidae)
No full textThis paper is concerned entirely with the members of the sub-family Theridiosomatinae, and is the third of a series with the above title (see Amer. Mus. Novitates, no. 1487 and no. 1502, 1951). The material on which the present study is based belongs largely to the collection in the American Museum of Natural History. Some material, especially that from the southern United States is in the collection of the author housed in the Alabama Museum of Natural History, University, Alabama. All the types and most of the paratypes are deposited in the American Museum of Natural History. The author again acknowledges his great indebtedness to the Department of Insects and Spiders of this institution and to the Council of the Scientific Staff for the grant enabling this study to be completed. Especial thanks are due to Dr. Willis J. Gertsch for counsel and encouragement given freely towards the completion of this study
W Harry Archer's collection of Horace Wells letters are still available. A commentary on a new publication
No full textThe definitive account of the life and work of Horace Wells, the dentist from Hartford, Connecticut, who experimented with nitrous oxide anesthesia in 1844, is that published by W Harry Archer for the centenary of Wells's work. A major source of original material was a collection of letters, by Wells and others, that Archer found in the house in Hartford, Vermont, in which Wells was born. In later support for Wells being better recognized for his role in the introduction of general anaesthesia, Richard J Wolfe and Leonard F Menczer published a collection of essays in 1994. However, their preparation was hampered by their (mis)understanding that the ‘Archer’ letters (which were lodged in the Pittsburgh University Library) were “missing”, a belief which continued, but has been disproved by a new author. Before his death, John Bunker encouraged his anthropologist daughter, Emily, to continue a project he had been planning on the history of anesthesia, and the result is a new book, “Horace and Elizabeth: Love and Death and Painless Dentistry”. First and foremost Ms Bunker has discovered that the Archer Letters are very much available, and has been greatly helped by the University of Pittsburgh Library in producing her book. She has used reproductions and transcriptions of the letters (some previously unpublished) and other contemporary documents to illustrate Wells's role in the great discovery. Some of the material, especially from before the ‘Colton’ demonstration of 1844 is remarkable; it is almost like hearing the story from Wells himself.</p
Distinct mesenchymal progenitor cell subsets in the adult human synovium
No full textObjective: To analyse the heterogeneity at the single-cell level of human mesenchymal progenitor cells from SM. Methods: Cell populations were enzymatically released from the knee joint synovium of adult human individuals. Single cell-derived clonal populations were obtained by limiting dilution and serially passaged to determine growth rates. Phenotypic analysis was carried out by flow cytometry. Replicative senescence was assessed by the senescence-associated β-galactosidase staining. Telomere lengths were determined semiquantitatively by Southern blotting. Telomerase activity was measured using a real-time quantitative telomerase repeat amplification procedure. Culture-expanded clonal populations were subjected to in vitro differentiation assays to investigate their mesenchymal multipotency. Results: The 50 clones analysed displayed wide variations in the proliferation rates, even within the same donor sample. The time taken to reach 20 population doublings ranged from 44 to 130 days. The phenotype of the clones tested was compatible with that of mesenchymal stem cells. Mean telomere lengths ranged from 5.2 to 10.9 kb with positive linear trend with telomerase activity, but no correlation with proliferative rates or cell senescence. All clones tested were capable of chondrogenic and osteogenic differentiation, though with large variability in potency. In contrast, only 30% of the clones were adipogenic. Conclusions: We report for the first time the co-existence, within the synovium, of progenitor cell subsets with distinct mesenchymal differentiation potency. Our findings further emphasize the need for strategies to purify cell populations with the clinically desired tissue formation potentials. © The Author 2009. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved
An investigation of the low energy RF plasma bombardment of thin film tin oxide surfaces
No full textThe work described in this thesis is concerned with enhancing the etch rate of fluorine doped tin oxide (SnO_2:F) under Ar/Cl_2 and Ar reactive ion etching conditions. The main project, involved analysing the silylation process for various silylation times, temperatures, and concentrations as a function of the photoresist etch rate in an argon plasma environment. This analysis led to the utilisation of an optimum silylation process (8 minutes at 50 deg. C 15 % Hexamethylcyclotrisilazane, HMCTS) that was found to enhance the resistance of the photoresist to etching by a factor of 12 in the 100% argon and by a factor of 1.8 in the argon chlorine case. The effect of silylation on the etch rate of the photoresist and tin oxide in an 90% Ar/10% Cl_2 plasma environment was investigated. It was found that the etch rate of the photoresist decreased whilst at the same time the etch rate of the tin oxide increased. In the 90% Ar/10% Cl_2 case it was observed that silylation enhanced the tin oxide etch rate by 25% for a 150 W plasma exposure compared to the non silylated case and by #approx# 10% compared to the non silylated case at 250 W and 350 W. A study on the etching of SnO_2:F, the transparent conductive electrode for flat panel displays, using an argon plasma was carried out. Four point probe (FPP) and talystep measurements have been used to monitor changes in the resistivity and the etch rate respectively over a range of etch times and powers (up to 15.5 minutes and 100 - 250W). XPS experiments have been performed in order to analyse the composition of the surface layers whilst optical emission spectroscopy (OES) enabled analysis of the species present in the plasma. The XPS results show a transition from Sn(IV) to Sn(II) and subsequently to metallic Sn. OES of argon plasmas under various pump down regimes have shown the presence of hydrogen in certain conditions and this appears to affect the subsequent modification of the SnO_2:F. In addition a Kelvin probe was used to measure the work function of SnO_2:F, enabling the chemical and physical changes at the surface to be monitored. Essential to this analysis was the calibration of the reference brass probe of the Kelvin probe, which led to establishment of a work function value for brass of 4.53 #+-# 0.06eV. Once established, utilising this work function value for brass was found to give a work function value for SnO_2:F of 4.73 #+-# 0.05 eV. The work function of SnO_2:F was then examined during argon etching in the presence of impurities for various etch times and powers. From the data recorded, it was found that the work function of SnO_2:F decreased immediately upon etching, progressing towards that of metallic tin (Sn"o) with increasing etch time and power. The observed decrease in the work function of SnO_2:F was ascribed to a combination of hydrogen adsorption at the surface creating a dipole layer and chemical etching of the constituent tin oxide atoms by reduction reactions producing a Sn excess. The presence of hydrogen in the short pump down (spd) but not in the lpd case indicated that hydrogen was the main species responsible for the change in the work function and resistivity and thus the effects of trace hydrogen impurities are postulated to be of significance in enhancing the etch rate of SnO_2:F. (author)Available from British Library Document Supply Centre-DSC:DXN033067 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
The influence of African sculpture on British art, 1910-1930
No full textThis thesis aims to discuss the influence of African wood sculpture
on British art from 1910 to 1930. It proposes that the works, tastes and
pronouncements of various 20th century British artists betray this
influence and that although the British artists did not initially
understand the conceptual foundations of African sculpture their limited
knowledge was just sufficient for the modernization of British art
through the adaptation of the formal qualities of African art.
In assessing the validity of these propositions the thesis examines
the factors and issues that facilitated the influence. Chapter 1
discusses the formal qualities of African wood sculpture that attracted
the British artists. It outlines the unusual figural proportions, the
free and direct use of planar, linear and solid geometry, the treatment
of material and its surfaces.
The conceptual foundations of African sculpture are generally
outlined in Chapter 2. The extent to which the British artists
understood these foundations is also discussed.
Chapter 3 concerns the introduction of African sculpture to Britain
and discusses the development of the anthropological and subsequent
aesthetic interest that it aroused. Both the Post-Impressionist
Exhibitions and the Omega Workshops which facilitated its influence are
examined. Chapter 4 examines the concept and attempts to categorize the
nature of this influence.
The last three chapters act as case studies in which the impact of
African sculpture on Epstein, Gaudier-Brzeska and Henry Moore is
examined. The conclusion discusses the term 'Primitive' and the British
artists and the 'Primitive
Bilateral and unilateral arm training improve motor function through differing neuroplastic mechanisms: a single-blinded randomized controlled trial
No full textBACKGROUND AND PURPOSE:
This randomized controlled trial tests the efficacy of bilateral arm training with rhythmic auditory cueing (BATRAC) versus dose-matched therapeutic exercises (DMTEs) on upper-extremity (UE) function in stroke survivors and uses functional magnetic resonance imaging (fMRI) to examine effects on cortical reorganization.
METHODS:
A total of 111 adults with chronic UE paresis were randomized to 6 weeks (3×/week) of BATRAC or DMTE. Primary end points of UE assessments of Fugl-Meyer UE Test (FM) and modified Wolf Motor Function Test Time (WT) were performed 6 weeks prior to and at baseline, after training, and 4 months later. Pretraining and posttraining, fMRI for UE movement was evaluated in 17 BATRAC and 21 DMTE participants.
RESULTS:
The improvements in UE function (BATRAC: FM Δ = 1.1 + 0.5, P = .03; WT Δ = -2.6 + 0.8, P < .00; DMTE: FM Δ = 1.9 + 0.4, P < .00; WT Δ = -1.6 + 0.7; P = .04) were comparable between groups and retained after 4 months. Satisfaction was higher after BATRAC than DMTE (P = .003). BATRAC led to significantly higher increase in activation in ipsilesional precentral, anterior cingulate and postcentral gyri, and supplementary motor area and contralesional superior frontal gyrus (P < .05). Activation change in the latter was correlated with improvement in the WMFT (P = .01).
CONCLUSIONS:
BATRAC is not superior to DMTE, but both rehabilitation programs durably improve motor function for individuals with chronic UE hemiparesis and with varied deficit severity. Adaptations in brain activation are greater after BATRAC than DMTE, suggesting that given similar benefits to motor function, these therapies operate through different mechanisms
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