4,303 research outputs found
Study of the angular coefficients and corresponding helicity cross sections of the W boson in hadron collisions
We present the Standard Model prediction for the eight angular coefficients
of the W boson, which completely describe its differential cross section in
hadron collisions. These coefficients are ratios of the W helicity cross
sections and the total unpolarized cross section. We also suggest a technique
to experimentally extract the coefficients.Comment: 8 pages, 13 figure
Nutritional Preferences Exhibited By Plants In Ad Libitum Feed Systems
Ad libitum feeding plant systems fitted with two reservoirs were used to monitor daily aqueous uptake by plants from paired reservoirs. When the reservoirs contained aqueous solutions of the same chemical composition, a plant accepted nourishment from alternate sources without bias; but when the reservoirs contained different aqueous solutions, i.e. either tap water or standard nutrient solution, a sharp bias was exhibited, depending on the plant\u27s need for mineral nutrient, which changed with time. Eventually a stable-end-state was attained, favoring water over the standard nutrient solution in the ratio of 3 to 1. When the plant was pruned severely, however, preference oscillated sharply from one source to the other for six months while new growth developed to reestablish the stable-end-state . If a toxic pollutant was added to the favored reservoir, the plants preference switched sharply to the other source until the toxicant was eliminated from. the polluted reservoir, thus ensuring the plants survival
ANOMALOUS GAUGE BOSON INTERACTIONS
We discuss the direct measurement of the trilinear vector boson couplings in
present and future collider experiments. The major goals of such experiments
will be the confirmation of the Standard Model (SM) predictions and the search
for signals of new physics. We review our current theoretical understanding of
anomalous trilinear gauge boson self-interactions. If the energy scale of the
new physics is TeV, these low energy anomalous couplings are expected
to be no larger than . Constraints from high precision
measurements at LEP and low energy charged and neutral current processes are
critically reviewed.Comment: 53 pages with 17 embedded figures, LaTeX, uses axodraw.sty, figures
available on request. The complete paper, is available at
ftp://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-871.ps.Z or
http://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-871.ps.Z Summary
of the DPF Working Subgroup on Anomalous Gauge Boson Interactions of the DPF
Long Range Planning Stud
Linear and nonlinear dynamics of a circular cylindrical shell under static and periodic axial load
In this paper an experimental study on circular cylindrical shells subjected to axial compres- sive and periodic loads is presented. The setting of the experiment is explained and deeply described along with a complete analysis of the results. The linear and the nonlinear dynamic behaviour associated with a combined effect of compressive static and a periodic axial load has been considered and a chaotic response of the structure has been observed close to the resonance. The linear shell behaviour is also investigated by means of a theoretical and finite element model, in order to enhance the comprehension of experimental results, i.e. the natural frequencies of the system and their ratios
Fibrotic and Vascular Remodelling of Colonic Wall in Patients with Active Ulcerative Colitis
open16noIntestinal fibrosis is a complication of inflammatory bowel disease [IBD]. Although fibrostenosis is a rare event in ulcerative colitis [UC], there is evidence that a fibrotic rearrangement of the colon occurs in the later stages. This is a retrospective study aimed at examining the histopathological features of the colonic wall in both short-lasting [SL] and long-lasting [LL] UC.
Surgical samples of left colon from non-stenotic SL [a parts per thousand currency sign 3 years, n = 9] and LL [a parts per thousand yen 10 years, n = 10] UC patients with active disease were compared with control colonic tissues from cancer patients without UC [n = 12] to assess: collagen and elastic fibres by histochemistry; vascular networks [CD31/CD105/nestin] by immunofluorescence; parameters of fibrosis [types I and III collagen, fibronectin, RhoA, alpha-smooth muscle actin [alpha-SMA], desmin, vimentin], and proliferation [proliferating nuclear antigen [PCNA]] by western blot and/or immunolabelling.
Colonic tissue from both SL-UC and LL-UC showed tunica muscularis thickening and transmural activated neovessels [displaying both proliferating CD105-positive endothelial cells and activated nestin-positive pericytes], as compared with controls. In LL-UC, the increased collagen deposition was associated with an up-regulation of tissue fibrotic markers [collagen I and III, fibronectin, vimentin, RhoA], an enhancement of proliferation [PCNA] and, along with a loss of elastic fibres, a rearrangement of the tunica muscularis towards a fibrotic phenotype.
A significant transmural fibrotic thickening occurs in colonic tissue from LL-UC, together with a cellular fibrotic switch in the tunica muscularis. A full-thickness angiogenesis is also evident in both SL- and LL-UC with active disease, as compared with controls.openIppolito, Chiara; Colucci, Rocchina; Segnani, Cristina; Errede, Mariella; Girolamo, Francesco; Virgintino, Daniela; Dolfi, Amelio; Tirotta, Erika; Buccianti, Piero; Di Candio, Giulio; Campani, Daniela; Castagna, Maura; Bassotti, Gabrio; Villanacci, Vincenzo; Blandizzi, Corrado; Bernardini, NunziaIppolito, Chiara; Colucci, ROCCHINA LUCIA; Segnani, Cristina; Errede, Mariella; Girolamo, Francesco; Virgintino, Daniela; Dolfi, Amelio; Tirotta, Erika; Buccianti, Piero; Di Candio, Giulio; Campani, Daniela; Castagna, Maura; Bassotti, Gabrio; Villanacci, Vincenzo; Blandizzi, Corrado; Bernardini, Nunzi
A study of atmospheric neutrinos with the IMB detector
A sample of 401 contained neutrino interactions collected in the 3300 metric ton fiducial mass IMB detector was used to study neutrino oscillations, geomagnetic modulation of the flux and to search for point sources. The majority of these events are attributed to neutrino interactions. For the most part, these neutrinos are believed to originate as tertiary products of cosmic ray interactions in the atmosphere. The neutrinos are a mixture of v sub e and v sub micron
Il mito dell’appartenenza. Politeia greca e civitas romana a confronto
This essay aims to investigate the origin of the concepts of citizenship and democracy through a reflection on the condition of the citizen in the poleis of ancient Greece – with a particular focus on legal systems in Sparta and Athens – and within the Roman Republic and Empire. Beyond the traditional (and simplistic) distinction between “Roman generosity” and “Greek avarice”, the landscape of ancient citizenship turns out to be very diverse and complex, regulated by the criteria for selecting the community of participants to political life; these criteria not only distinguish the Roman world from the Greek one, but also the Spartan polites from the Athenian one. The present reflection, which is not limited to a mere description of ancient legal systems, means to emphasise how much the concept of citizenship, since the beginnings of Western culture, was closely linked to the dichotomy inclusion/exclusion, to a strongly and meticulously hierarchized politics, to the interpretation of the border as entry threshold for the foreigner, but also as an instrument of expansion and conquest. Citizenship; Democracy; Inclusion; Polis; Rome
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