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171.
Carlsson J Andér M Nervall M Aqvist J 《The journal of physical chemistry. B》2006,110(24):12034-12041
The linear interaction energy (LIE) method in combination with two different continuum solvent models has been applied to calculate protein-ligand binding free energies for a set of inhibitors against the malarial aspartic protease plasmepsin II. Ligand-water interaction energies are calculated from both Poisson-Boltzmann (PB) and Generalized Born (GB) continuum models using snapshots from explicit solvent simulations of the ligand and protein-ligand complex. These are compared to explicit solvent calculations, and we find close agreement between the explicit water and PB solvation models. The GB model overestimates the change in solvation energy, and this is caused by consistent underestimation of the effective Born radii in the protein-ligand complex. The explicit solvent LIE calculations and LIE-PB, with our standard parametrization, reproduce absolute experimental binding free energies with an average unsigned error of 0.5 and 0.7 kcal/mol, respectively. The LIE-GB method, however, requires a constant offset to approach the same level of accuracy. 相似文献
172.
Marijke WA de Backer Carlos P Fitzsimons Maike AD Brans Mieneke CM Luijendijk Keith M Garner Erno Vreugdenhil Roger AH Adan 《BMC neuroscience》2010,11(1):81
Background
This study compared the transduction efficiencies of an adeno-associated viral (AAV) vector, which was pseudotyped with an AAV1 capsid and encoded the green fluorescent protein (GFP), with a lentiviral (LV) vector, which was pseudotyped with a VSV-G envelop and encoded the discosoma red fluorescent protein (dsRed), to investigate which viral vector transduced the lateral hypothalamus or the amygdala more efficiently. The LV-dsRed and AAV1-GFP vector were mixed and injected into the lateral hypothalamus or into the amygdala of adult rats. The titers that were injected were 1 × 108 or 1 × 109 genomic copies of AAV1-GFP and 1 × 105 transducing units of LV-dsRed. 相似文献173.
The equations of magnetostatic equilibria for a plasma in agravitational field are investigated analytically. For equilibriawith an ignorable spatial coordinate, the equations reduce toa single nonlinear elliptic equation for the magnetic potentialu known as the Grad-Shafranov equation. By specifying the arbitraryfunctions in this equation, a Liouville equation is obtained.Bäcklund transformations are described and applied to obtainexact solutions for the Liouville equation modelling an isothermalmagnetostatic atmosphere, in which the current density J isproportional to the exponential of the magnetic potential andmoveover falls off exponentially with distance vertical to thebase with an e-folding distance equal to the gravitational scaleheight. 相似文献
174.
175.
R. A. Bark P. Bosetti G. B. Hagemann H. Ryde A. Brockstedt H. Carlsson L. P. Ekström A. Nordlund B. Herskind S. Leoni A. Bracco F. Camera S. Frattini M. Mattiuzzi B. Million C. Rossi-Alvarez G. de Angelis D. Bazzacco S. Lunardi M. De Poli 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(1):5-6
High-spin states of the doubly-odd 112Sb were studied by in-beam spectroscopy using the 88Sr (28Si, p3n) and 89Y (29Si, α2n) fusion-evaporation reactions at beam energies of 120 and 108 MeV, respectively. γ?γ, charged particle-γ?γ coincidences, and γ?γ angular correlation analyses were employed for determining the level scheme of 112Sb. In the present work, all the levels except for low-lying states in 112Sb were newly established. Two ΔI = 1 strongly coupled bands were observed; one is a negative-parity band that is similar to those observed in the neighboring doubly-odd Sb isotopes and the other is a positive-parity band that has a new type structure not observed in the other isotopes. From the similarity of the properties of these ΔI = 1 bands to the bands built on 9/2+ 2p?1h states in the odd-A Sb isotopes, we suggest that these two ΔI = 1 bands should be associated with the [π(g9/2)?1 ? νh11/2] and [π(g9/2)?1νg7/2] configurations, respectively. 相似文献
176.
Lillie R. Cavonius Nils-Gunnar Carlsson Ingrid Undeland 《Analytical and bioanalytical chemistry》2014,406(28):7313-7322
Determination of microalgaes’ fatty acid content is often done with chloroform and methanol according to the Bligh and Dyer extraction, though faster methods exist. A number of comparisons between the Bligh and Dyer and faster methods have resulted in contradicting data, possibly due to differences in algae used and the different versions of the Bligh and Dyer method applied. Here, various forms of direct-transesterification (D-TE) and two-step transesterification (2-TE), including three versions developed in our lab, are compared with the original Bligh and Dyer (Can J Biochem Physiol 37: 911–917, 1959) extraction and two modifications thereof (Lee et al. J AOAC Int 79:487–492, 1996, and our own acidified version) on microalgae with different cell walls: Isochrysis galbana, Nannochloropsis oculata, and Phaeodactylum tricornutum. In total, fatty acid extracts from 11 methods were separated and quantified by gas chromatography with mass spectrometry. Results show that, for N. oculata and P. tricornutum, methods based on chloroform–methanol underestimated the fatty acid content compared with the 2-TE and D-TE methods, which gave similar results. Moreover, D-TE methods are faster than chloroform–methanol methods and use chemicals that are less toxic. Of the D-TE methods, the ones using hydrochloric acid and sulfuric acid recovered the most fatty acids, while boron trifluoride recovered slightly less. The main qualitative difference between the fatty acids recovered was that the chloroform–methanol methods recovered less saturated fatty acids in P. tricornutum. 相似文献
177.
We use filtered modules over a Noetherian ring and fibred bounded control on homomorphisms to construct a new kind of controlled algebra with applications in geometric topology. The resulting theory can be thought of as a “pushout” of bounded K-theory with fibred control and bounded G-theory constructed and used by the authors. Bounded G-theory was geared toward constructing a G-theoretic version of assembly maps and proving the Novikov injectivity conjecture for them. The G-theory with fibred control is needed in the study of surjectivity of the assembly map. The relation between the K- and G-theories is the classical one: K-theory is meaningful, however G-theory is easier to compute, and the relationship is expressed via a Cartan map. This map turns out to be an equivalence under very mild constraints in terms of metric geometry such as finite decomposition complexity. The fibred theory is certainly more complicated than the absolute theory. This paper contains the non-equivariant theory including fibred controlled excision theorems known to be crucial for computations. 相似文献
178.
A method for the experimental determination of the through-thickness residual stress distribution in paperboard is presented.
The successive removal of thin layers from strips of board through surface grinding changes the stress-state and the bending
stiffness resulting in a changed curvature, which is measurable. From tests of strips in both in-plane directions, stress
distributions can then be evaluated using the Treuting-Read method. Geometrically nonlinear effects at the large deformations
taking place are avoided through a proper choice of strip dimensions. Typical results are presented and factors influencing
the accuracy of the determination are thoroughly discussed. 相似文献
179.
180.
Gunnar Carlsson 《K-Theory》1995,9(4):305-322
Although theK-theory functor on the category of symmetric monoidal categories preserves finite products for essentially trivial reasons, this is not so in the case of infinite products. In this paper, we show that in factK-theory does preserve infinite products, but for non-trivial reasons.Supported in part by NSF DMS 9209714. 相似文献