2,328 research outputs found
In Situ Characterisation of Permanent Magnetic Quadrupoles for focussing proton beams
High intensity laser driven proton beams are at present receiving much
attention. The reasons for this are many but high on the list is the potential
to produce compact accelerators. However two of the limitations of this
technology is that unlike conventional nuclear RF accelerators lasers produce
diverging beams with an exponential energy distribution. A number of different
approaches have been attempted to monochromise these beams but it has become
obvious that magnetic spectrometer technology developed over many years by
nuclear physicists to transport and focus proton beams could play an important
role for this purpose. This paper deals with the design and characterisation of
a magnetic quadrupole system which will attempt to focus and transport
laser-accelerated proton beams.Comment: 20 pages, 42 figure
Seed enhancements
Seed enhancements may be defined as post-harvest treatments that improve germination or seedling growth, or facilitate the delivery of seeds and other materials required at the time of sowing. This definition includes three general areas of enhancements: pre-sowing hydration treatments (priming), coating technologies and seed conditioning. Pre-sowing hydration treatments include non-controlled water uptake systems (methods in which water is freely available and not restricted by the environment) and controlled systems (methods that regulate seed moisture content preventing the completion of germination). Three techniques are used for controlled water uptake: priming with solutions or with solid particulate systems or by controlled hydration with water. These priming techniques will be discussed in this paper with reference to methodology, protocol optimization, drying and storage. Coating technologies include pelleting and film coating, and coatings may serve as delivery systems. Seed conditioning equipment upgrades seed quality by physical criteria. Integration of these methods can be performed, and a system is described to upgrade seed quality in Brassica that combines hydration, coating and conditioning. Upgrading is achieved by detecting sinapine leakage from nonviable seeds in a coating material surrounding the seeds. Seed-coat permeability directly influences leakage rate, and seeds of many species have a semipermeable layer. The semipermeable layer restricts solute diffusion through the seed coat, while water movement is not impeded. Opportunities for future seed enhancement research and development are highlighte
Incidence and time course of everolimus-related adverse events in postmenopausal women with hormone receptor-positive advanced breast cancer: insights from BOLERO-2.
BackgroundIn the BOLERO-2 trial, everolimus (EVE), an inhibitor of mammalian target of rapamycin, demonstrated significant clinical benefit with an acceptable safety profile when administered with exemestane (EXE) in postmenopausal women with hormone receptor-positive (HR(+)) advanced breast cancer. We report on the incidence, time course, severity, and resolution of treatment-emergent adverse events (AEs) as well as incidence of dose modifications during the extended follow-up of this study.Patients and methodsPatients were randomized (2:1) to receive EVE 10 mg/day or placebo (PBO), with open-label EXE 25 mg/day (n = 724). The primary end point was progression-free survival. Secondary end points included overall survival, objective response rate, and safety. Safety evaluations included recording of AEs, laboratory values, dose interruptions/adjustments, and study drug discontinuations.ResultsThe safety population comprised 720 patients (EVE + EXE, 482; PBO + EXE, 238). The median follow-up was 18 months. Class-effect toxicities, including stomatitis, pneumonitis, and hyperglycemia, were generally of mild or moderate severity and occurred relatively early after treatment initiation (except pneumonitis); incidence tapered off thereafter. EVE dose reduction and interruption (360 and 705 events, respectively) required for AE management were independent of patient age. The median duration of dose interruption was 7 days. Discontinuation of both study drugs because of AEs was higher with EVE + EXE (9%) versus PBO + EXE (3%).ConclusionsMost EVE-associated AEs occur soon after initiation of therapy, are typically of mild or moderate severity, and are generally manageable with dose reduction and interruption. Discontinuation due to toxicity was uncommon. Understanding the time course of class-effect AEs will help inform preventive and monitoring strategies as well as patient education.Trial registration numberNCT00863655
The algebra of adjacency patterns: Rees matrix semigroups with reversion
We establish a surprisingly close relationship between universal Horn classes
of directed graphs and varieties generated by so-called adjacency semigroups
which are Rees matrix semigroups over the trivial group with the unary
operation of reversion. In particular, the lattice of subvarieties of the
variety generated by adjacency semigroups that are regular unary semigroups is
essentially the same as the lattice of universal Horn classes of reflexive
directed graphs. A number of examples follow, including a limit variety of
regular unary semigroups and finite unary semigroups with NP-hard variety
membership problems.Comment: 30 pages, 9 figure
Artemisia extracts activate PPARγ, promote adipogenesis, and enhance insulin sensitivity in adipose tissue of obese mice
Objective: Studies have shown that the inability of adipose tissue to properly expand during the obese state or respond to insulin can lead to metabolic dysfunction. Artemisia is a diverse group of plants that has a history of medicinal use. The aim of this study was to examine the ability of ethanolic extracts of Artemisia scoparia (SCO) and Artemisia santolinifolia (SAN) to modulate adipocyte development in cultured adipocytes and white adipose tissue (WAT) function invivo using a mouse model of diet-induced obesity. Method: Adipogenesis was assessed using Oil Red O staining and immunoblotting. A nuclear receptor specificity assay was used to examine the specificity of SCO- and SAN-induced PPARγ activation. C57BL/6J mice, fed a high-fat diet, were gavaged with saline, SCO, or SAN for 2 wk. Whole-body insulin sensitivity was examined using insulin tolerance tests. WAT depots were assessed via immunoblotting for markers of insulin action and adipokine production. Results: We established that SCO and SAN were highly specific activators of PPARγ and did not activate other nuclear receptors. After a 1-wk daily gavage, SCO- and SAN-treated mice had lower insulin-induced glucose disposal rates than control mice. At the end of the 2-wk treatment period, SCO- and SAN-treated mice had enhanced insulin-responsive Akt serine-473 phosphorylation and significantly decreased monocyte chemotactic protein-1 levels in visceral WAT compared with control mice; these differences were depot specific. Moreover, plasma adiponectin levels were increased following SCO treatment. Conclusion: Overall, these studies demonstrate that extracts from two Artemisia species can have metabolically favorable effects on adipocytes and WAT. © 2014 Elsevier Inc
Neutron-Capture Elements in the Early Galaxy: Insights from a Large Sample of Metal-Poor Giants
New abundances for neutron-capture (n-capture) elements in a large sample of
metal-poor giants from the Bond survey are presented. The spectra were acquired
with the KPNO 4-m echelle and coude feed spectrographs, and have been analyzed
using LTE fine-analysis techniques with both line analysis and spectral
synthesis. Abundances of eight n-capture elements (Sr, Y, Zr, Ba, La, Nd, Eu,
Dy) in 43 stars have been derived from blue (lambda = 4070--4710, R~20,000, S/N
ratio~100-200) echelle spectra and red (lambda = 6100--6180, R~22,000, S/N
ratio~100-200) coude spectra, and the abundance of Ba only has been derived
from the red spectra for an additional 27 stars. Overall, the abundances show
clear evidence for a large star-to-star dispersion in the heavy element-to-iron
ratios. The new data also confirm that at metallicities [Fe/H] <~ --2.4, the
abundance pattern of the heavy (Z >= 56) n-capture elements in most giants is
well-matched to a scaled Solar System r-process nucleosynthesis pattern. The
onset of the main r-process can be seen at [Fe/H] ~ --2.9. Contributions from
the s-process can first be seen in some stars with metallicities as low as
[Fe/H] ~ --2.75, and are present in most stars with metallicities [Fe/H] >
--2.3. The lighter n-capture elements (Sr-Y-Zr) are enhanced relative to the
heavier r-process element abundances. Their production cannot be attributed
solely to any combination of the Solar System r- and main s-processes, but
requires a mixture of material from the r-process and from an additional
n-capture process which can operate at early Galactic time.Comment: Text + 5 Tables and 11 Figures: Submitted to the Astrophysical
Journa
Hunting for the New Symmetries in Calabi-Yau Jungles
It was proposed that the Calabi-Yau geometry can be intrinsically connected
with some new symmetries, some new algebras. In order to do this it has been
analyzed the graphs constructed from K3-fibre CY_d (d \geq 3) reflexive
polyhedra. The graphs can be naturally get in the frames of Universal
Calabi-Yau algebra (UCYA) and may be decode by universal way with changing of
some restrictions on the generalized Cartan matrices associated with the Dynkin
diagrams that characterize affine Kac-Moody algebras. We propose that these new
Berger graphs can be directly connected with the generalizations of Lie and
Kac-Moody algebras.Comment: 29 pages, 15 figure
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