| 1. |
- Dawson, K. S., et al.
(författare)
-
An Intensive Hubble Space Telescope Survey for z>1 Type Ia Supernovae by Targeting Galaxy Clusters
- 2009
-
Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 138, s. 1271-1283
-
Tidskriftsartikel (refereegranskat)abstract
- We present a new survey strategy to discover and study high-redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9 < z < 1.5, we obtain a twofold improvement in the efficiency of finding SNe compared to an HST field survey and a factor of 3 improvement in the total yield of SN detections in relatively dust-free red-sequence galaxies. In total, sixteen SNe were discovered at z>0.95, nine of which were in galaxy clusters. This strategy provides an SN sample that can be used to decouple the effects of host-galaxy extinction and intrinsic color in high-redshift SNe, thereby reducing one of the largest systematic uncertainties in SN cosmology. Based on observations made with the NASA/ESA Hubble Space Telescope and obtained from the data archive at the Space Telescope Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555. The observations are associated with program 10496.
|
|
| 2. |
- Dey, Raja, 1963, et al.
(författare)
-
21-Acetoxy-17α-4-pregnene-3,20-dione
- 2005
-
Ingår i: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; 61:4
-
Tidskriftsartikel (refereegranskat)abstract
- The synthetic steroid 21-acetoxy-17α-4-pregnene-3,20-dione, C 23H32O4, crystallizes with a single molecule in the asymmetric unit. The molecule contains four fused rings, typical of steroids. The cyclohexene ring A has nearly the conformation of a boat. One saturated six-membered ring, B, is intermediate between chair and half-chair conformations, while the other six-membered ring, C, is essentially a chair. The five-membered ring D tends towards a twist conformation. The ring junction A/B is quasi-trans, whereas the ring junctions B/C and C/D are both trans. The molecule is slightly convex towards the β side.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Dey, Raja, 1963, et al.
(författare)
-
21-Deoxycortisone (17α-hydroxy-4-pregnene-3,11,20-trione)
- 2005
-
Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C61:4, s. o201-o203
-
Tidskriftsartikel (refereegranskat)abstract
- The title compound, C21H28O4, a synthetic glucocorticoid, crystallizes with a single molecule in the asymmetric unit. Ring A is almost in a half-chair conformation, rings B and C are almost in chair conformations, and ring D is between a twist and a 13β-envelope conformation. The A/B ring junction is quasi-trans, whereas the B/C and C/D ring junctions both approach trans characteristics. The molecule as a whole is slightly convex towards the β side, with an angle of 9.60(2)° between the C10-C19 and C13-C18 vectors. Molecular-packing and hydrogen-bonding (both intra- and intermolecular) interactions play a major role in the structural association of the compound.
|
|
| 6. |
|
|
| 7. |
- Krengel, Ute, 1964, et al.
(författare)
-
Preliminary X-ray crystallographic analysis of the secreted chorismate mutase from Mycobacterium tuberculosis: A tricky crystallization problem solved
- 2006
-
Ingår i: Acta Crystallographica Section F: Structural Biology and Crystallization Communications. - 1744-3091. ; 62:5, s. 441-445
-
Tidskriftsartikel (refereegranskat)abstract
- Chorismate mutase catalyzes the conversion of chorismate to prephenate in the biosynthesis of the aromatic amino acids tyrosine and phenylalanine in bacteria, fungi and plants. Here, the crystallization of the unusual secreted chorismate mutase from Mycobacterium tuberculosis (encoded by Rv1885c), a 37.2 kDa dimeric protein belonging to the AroQγ subclass of mutases, is reported. Crystal optimization was non-trivial and is discussed in detail. To obtain crystals of sufficient quality, it was critical to initiate crystallization at higher precipitant concentration and then transfer the drops to lower precipitant concentrations within 5-15 min, in an adaptation of a previously described technique [Saridakis & Chayen (2000), Protein Sci. 9, 755-757]. As a result of the optimization, diffraction improved from 3.5 to 1.3 Å resolution. The crystals belong to space group P21, with unit-cell parameters a = 42.6, b = 72.6, c = 62.0 Å., β = 104.5°. The asymmetric unit contains one biological dimer, with 167 amino acids per protomer. A soak with a transition-state analogue is also described.
|
|
| 8. |
- Langhorne, P, et al.
(författare)
-
Is stroke unit care portable? A systematic review of the clinical trials
- 2005
-
Ingår i: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 34:4, s. 324-330
-
Tidskriftsartikel (refereegranskat)abstract
- Background: It is not known if mobile stroke teams can achieve the good results seen in trials of geographically discrete stroke wards (stroke units). Objective: To establish the effectiveness of mobile stroke teams. Design: Systematic review of controlled clinical trials that compared peripatetic systems of organised stroke care (stroke team care) with alternative hospital services. Methods: Systematic review and meta-analysis (using Cochrane Collaboration methodology and involving the primary trialists). Clinical outcomes included death, dependency, the need for institutional care and measures of the process of care such as the delivery of key investigations and treatments. Results: Six clinical trials (1,085 patients) were identified, five (781 patients) compared some form of stroke team care with conventional care in general medical wards and one (304 patients) compared team care with a comprehensive stroke unit. Compared with care in general wards, stroke team care improved some aspects of the process of care, but clinical outcomes were similar. Compared with a comprehensive stroke unit, stroke team patients were significantly less likely to survive (P< 0.001), return home (P< 0.001) or regain independence (P< 0.0001). Most aspects of the process of care were also poorer than in the stroke unit. Conclusions: Care from a mobile stroke team had no major impact on death, dependency or the need for institutional care. © The Author 2005. Published by Oxford University Press. All rights reserved.
|
|
| 9. |
|
|
| 10. |
- Singh, R.N., et al.
(författare)
-
Influence of temperature on threshold stress for reorientation of hydrides and residual stress variation across thickness of Zr-2.5Nb alloy pressure tube
- 2006
-
Ingår i: Journal of Nuclear Materials. - : Elsevier BV. - 0022-3115 .- 1873-4820. ; 359:3, s. 208-249
-
Tidskriftsartikel (refereegranskat)abstract
- Threshold stress, σth, for reorientation of hydrides in cold worked and stress-relieved (CWSR) Zr–2.5Nb pressure tube material was determined in the temperature range of 523–673 K. Using tapered gage tensile specimen, mean value of σth was experimentally determined by two methods, half thickness method and area compensation method. The difference between local values of σth measured across the thickness of the tube and the mean σth values yielded the residual stress variation across the tube thickness. It was observed that both the mean threshold stress and residual stress decrease with increase in reorientation temperature. Also, the maximum value of residual stresses was observed near the midsection of the tube.
|
|
