947 research outputs found
Some optics alternatives for the FFS
The evolution of the SLC Final Focus System (FFS) has been discussed in the SLC Red Books and various collider notes. Bulos and Brown and Murray were able to achieve small ..beta..'s with large l/sub 1/'s (the distance between the IP and the effective field boundary of the first quad). However, all current solutions which are compatible with the known constraints of the total path length, aperture and spot size require high gradient, superconducting quads. Such quads cannot be expected to provide very good inherent field quality (i.e., without correction windings) but can be expected to be comparatively expensive to build and operate simply. The purpose of this note is to present a more general solution for the FFS telescope which is compatible with the known constraints of detectors, magnet types, available space and the ingoing and outgoing phase space expectations. While a number of different solutions were found, the ones presented provide comparable performance, simpler operation and lower costs. The gradients are sufficiently low to allow the use of conventional electromagnets, intrinsic or cryostable superconducting or rare earth permanent (REP) magnets or any arbitary combination of all of these magnet types. 8 references, 9 figures, 1 table
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A study of organotitanium coupling agents for adhesion promotion and of chemical reactions on alumina surfaces by inelastic electron tunnelling spectroscopy
Chemical reactions taking place on an alumina surface have been investigated by incorporating this surface within an Al-AlOx~Pb tunnelling junction and scanning the inelastic electron tunnelling spectrum.
This approach has been employed to study reactions involved in substrate-coating situations, of particular relevance to adhesive bonding. It has been shown that the glass-fibre circuit board (PCB) substrates used in this study may be reused after suitable cleaning. A "dry atmosphere" bag has been incorporated into the procedure to facilitate the doping and subsequent study of air- sensitive materials.
Three organotitanium compounds; titanium acetyl-acetonate (TAA), triethanolamine titanate (TEAT) and octylene glycol titanate (OGT), which are used commercially as primers or adhesion promoters for surface coatings have been investigated. Mechanisms of their solution hydrolysis and of their interaction with the alumina surface are proposed. The interaction of these primed alumina surfaces with simulated organic coating bases has also been studied. Hence a mechanism for the interaction of a coating promoter with both a metal oxide surface and with the surface coating itself has been evaluated.
In addition, since atmospheric surface contamination will undoubtedly affect any subsequent process, the surface reactions of simple gaseous molecules on alumina have been investigated. These have incidentally thrown light onto the mineralogical theory of the origin of life. The first experimental support for Bernal and Cairns-Smith's mineralogical theory for the origin of life has been established by demonstrating that an alumina surface incorporated in a tunnel junction has the catalytic ability to synthesize amino acids from ammonia, water and carbon dioxide, and sugars from wet carbon monoxide or formaldehyde. These reactants were likely components of the earth's prebiotic atmosphere. The role of such an inorganic template in the surface catalyzed theory of the origin of life is considered
Accessing elite nurses for research: reflections on the theoretical and practical issues of telephone interviewing
Elite groups are interesting as they frequently are powerful (in terms of position, knowledge and influence) and enjoy considerable authority. It is important, therefore, to involve them in research concerned with understanding social contexts and processes. This is particularly pertinent in healthcare, where considerable strategic development and change are features of everyday practice that may be guided or perceived as being guided, by elites.
This paper evolved from a study investigating the availability and role of nurses whose remit involved leading nursing research and development within acute NHS Trusts in two health regions in Southern England. The study design included telephone interviews with Directors of Nursing Services during which time the researchers engaged in a reflective analysis of their experiences of conducting research with an `elite' group. Important issues identified were the role of gatekeepers, engagement with elites and the use of the telephone interview method in this context. The paper examines these issues and makes a case for involving executive nurses in further research. The paper also offers strategies to help researchers design and implement telephone interview studies successfully to maximise access to the views and experiences of `hard to reach groups', such as elites, while minimising the associated disruption
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Structure Loaded Vacuum Laser-Driven Particle Acceleration Experiments at SLAC
We present an overview of the future laser-driven particle acceleration experiments. These will be carried out at the E163 facility at SLAC. Our objectives include a reconfirmation of the proof-of-principle experiment, a staged buncher laser-accelerator experiment, and longer-term future experiments that employ dielectric laser-accelerator microstructures
Results of Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) trial
BACKGROUND: Restenosis after percutaneous coronary intervention (PCI) is a major problem affecting 15% to 30% of patients after stent placement. No oral agent has shown a beneficial effect on restenosis or on associated major adverse cardiovascular events. In limited trials, the oral agent tranilast has been shown to decrease the frequency of angiographic restenosis after PCI. METHODS AND RESULTS: In this double-blind, randomized, placebo-controlled trial of tranilast (300 and 450 mg BID for 1 or 3 months), 11 484 patients were enrolled. Enrollment and drug were initiated within 4 hours after successful PCI of at least 1 vessel. The primary end point was the first occurrence of death, myocardial infarction, or ischemia-driven target vessel revascularization within 9 months and was 15.8% in the placebo group and 15.5% to 16.1% in the tranilast groups (P=0.77 to 0.81). Myocardial infarction was the only component of major adverse cardiovascular events to show some evidence of a reduction with tranilast (450 mg BID for 3 months): 1.1% versus 1.8% with placebo (P=0.061 for intent-to-treat population). The primary reason for not completing treatment was > or =1 hepatic laboratory test abnormality (11.4% versus 0.2% with placebo, P<0.01). In the angiographic substudy composed of 2018 patients, minimal lumen diameter (MLD) was measured by quantitative coronary angiography. At follow-up, MLD was 1.76+/-0.77 mm in the placebo group, which was not different from MLD in the tranilast groups (1.72 to 1.78+/-0.76 to 80 mm, P=0.49 to 0.89). In a subset of these patients (n=1107), intravascular ultrasound was performed at follow-up. Plaque volume was not different between the placebo and tranilast groups (39.3 versus 37.5 to 46.1 mm(3), respectively; P=0.16 to 0.72). CONCLUSIONS: Tranilast does not improve the quantitative measures of restenosis (angiographic and intravascular ultrasound) or its clinical sequelae
Macrophage polarisation affects their regulation of trophoblast behaviour
Introduction
During the first trimester of human pregnancy, fetally-derived extravillous trophoblast (EVT) cells invade into uterine decidua and remodel the uterine spiral arteries to ensure that sufficient blood reaches the maternal-fetal interface. Decidual macrophages have been implicated in the regulation of decidual remodelling and aberrant activation of these immune cells is associated with pre-eclampsia.
Methods
The monocytic cell line THP-1 was activated to induce an M1 or M2 phenotype and the conditioned media was used to treat the EVT cell line SGHPL-4 in order to determine the effect of macrophage polarisation on trophoblast behaviour in-vitro. SGHPL-4 cell functions were assessed using time-lapse microscopy, endothelial-like tube formation assays and western blot.
Results
The polarisation state of the THP-1 cells was found to differentially alter the behaviour of trophoblast cells in-vitro with pro-inflammatory M1 conditioned media significantly inhibiting trophoblast motility, impeding trophoblast tube formation, and inducing trophoblast expression of caspase 3, when compared to anti-inflammatory M2 conditioned media.
Discussion
Macrophages can regulate trophoblast functions that are critical during decidual remodelling in early pregnancy. Importantly, there is differential regulation of trophoblast function in response to the polarisation state of these cells. Our studies indicate that the balance between a pro- and anti-inflammatory environment is important in regulating the cellular interactions at the maternal-fetal interface and that disturbances in this balance likely contribute to pregnancy disorders associated with poor trophoblast invasion and vessel remodelling
Catholic Healthcare Organizations and the Articulation of Their Identity
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69947.pdf (publisher's version ) (Open Access
Study of the B^0 Semileptonic Decay Spectrum at the Upsilon(4S) Resonance
We have made a first measurement of the lepton momentum spectrum in a sample
of events enriched in neutral B's through a partial reconstruction of B0 -->
D*- l+ nu. This spectrum, measured with 2.38 fb**-1 of data collected at the
Upsilon(4S) resonance by the CLEO II detector, is compared directly to the
inclusive lepton spectrum from all Upsilon(4S) events in the same data set.
These two spectra are consistent with having the same shape above 1.5 GeV/c.
From the two spectra and two other CLEO measurements, we obtain the B0 and B+
semileptonic branching fractions, b0 and b+, their ratio, and the production
ratio f+-/f00 of B+ and B0 pairs at the Upsilon(4S). We report b+/b0=0.950
(+0.117-0.080) +- 0.091, b0 = (10.78 +- 0.60 +- 0.69)%, and b+ = (10.25 +- 0.57
+- 0.65)%. b+/b0 is equivalent to the ratio of charged to neutral B lifetimes,
tau+/tau0.Comment: 14 page, postscript file also available at
http://w4.lns.cornell.edu/public/CLN
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