Sökresultat

Filtyp

Din sökning på "*" gav 535653 sökträffar

NMR studies of the E140Q mutant of the carboxy-terminal domain of calmodulin reveal global conformational exchange in the Ca2+-saturated state

In the present investigation, the Ca2+ activation of the C-terminal domain of bovine calmodulin and the effects of replacing the bidentate Ca2+-coordinating glutamic acid residue in the 12th and last position of loop IV with a glutamine are studied by NMR spectroscopy. The mutation E140Q results in sequential Ca2+ binding in this domain and has far-reaching effects on the structure of (Ca2+)2 TR2C

Nuclear spin quenching a new probe of exchange kinetics and droplet size in disperse systems

A new experimental technique, nuclear spin quenching (NSQ), is introduced, which can be used to measure droplet size and inter-droplet exchange rates of various intrinsic molecular species in disperse systems. The physical basis of the method is the quenching of the fine structure in spin-coupled N.M.R. spectra by intermolecular proton exchange, the rate of which is controlled by droplet exchange.

Sequence dependence and direct measurement of crossover isomer distribution in model Holliday junctions using NMR spectroscopy

A 32-base-pair model of the Holliday junction (HJ) intermediate in genetic recombination has been prepared and analyzed in-depth by 2D and 3D 1H NMR spectroscopy. This HJ (J2P1) corresponds to a cyclic permutation of the base pairs at the junction relative to a previously studied HJ [J2; Chen, S.-M., and Chazin, W. J. (1994) Biochemistry 33, 11453-11459], designed to probe the effect of the sequen

Shape fluctuations and water diffusion in microemulsion droplets : A nuclear spin relaxation study

Water 2H and 17O spin relaxation data for the microemulsion phase in the AOT/D 2O/isooctane system are reported. The difference between the transverse (R 2) and the longitudinal (R 1) relaxation rates has been measured as function of droplet size, droplet volume fraction, temperature, and resonance frequency. The 2H longitudinal relaxation rate dispersion has been measured over an extensive freque

Water Dynamics in Microemulsion Droplets. A Nuclear Spin Relaxation Study

The state of water in aqueous microemulsion droplets in the system AOT/D2O/isooctane has been investigated by 2H and 17O NMR. Longitudinal relaxation rates are reported as a function of droplet size, droplet volume fraction, temperature, and resonance frequency. We conclude that the surface-induced perturbation of water rotation is of short range (limited to the primary hydration of the AOT head g

Primary care doctor fostering and clinical research training in Sweden : Implications for Japan

In 2018, a new training program for primary care physicians was launched in Japan. As physicians responsible for the training of new primary care physicians, we have faced many problems, particularly in rural areas. The influence of this new program on primary care physicians in rural areas of Japan has not been sufficiently investigated. The aim of this research was to improve training for primar

Hydration of ionic surfactant micelles from water oxygen-17 magnetic relaxation

Water oxygen-17 relaxation rates have been measured for aqueous solutions of micelles composed of ionic surfactants of varying alkyl chain length, head group, and counterion. The concentration of surfactant and salt was also varied. From these measurements, supplemented with relaxation data for short-chain molecules and with quadrupolar splittings from anisotropic mesophases, we derive structural

Visualization of adult fish lens fiber cells

The crystalline lens of a vertebrate eye is a gradient-index lens and grows throughout life by addition of new lens fiber cells in the periphery. In fish, the growing ball-shaped lens maintains sophisticated optical properties throughout life by maintaining the distribution of refractive index relative to the increasing radius of the lens. During this process, the central fibers must increase refr

Participation weighting based on sociodemographic register data improved external validity in a population-based cohort study

Objective: To investigate whether inverse probability of participation weighting (IPPW) using register data on sociodemographic and disease history variables can improve external validity in a cohort study with selective participation. Study Design and Setting: We fitted various IPPW models by logistic regression using register data for the participants (n = 1,111) and nonparticipants (n = 1,132)

Constructing a typology of virtual city brand co-creation practices: an ecological approach

PurposeThe paper aims to offer an approach that allows an analysis and construction of a typology of virtual city brand co-creation practices.Design/methodology/approachThe approach is illustrated by using data collected in regard to the branding of Stockholm; it is based on visual representations expressing the process in which brand co-creation unfolds in a network of different affective modalit

Sound Art : The First 100 Years of an Aggressively Expanding Artform

"A brief history of sound art is, in a nutshell, a history of sonic forms of expression that throughout the twentieth century can be traced within music, the visual arts, and contemporary dance, as well as in performance art, conceptual art, and media art. Attempts to capture sound art as a detached and isolated art form or artistic phenomenon have been made, but this is definitely not the approac

An evolving risk perspective for policy instrument choice in sustainability transitions

We develop the concept of evolving risk to demonstrate that the optimal policy choice between price and quantity instruments may change over time. Drawing from system innovation, evolutionary concepts and modern financial and transaction cost economics, we analyze dynamic cost and welfare impacts of instrument choice under uncertainty. In early market deployment of niche technologies, economic and

Performance analysis of a heat transfer and sub-grid chemical reaction distributed activation energy model for fire simulations

A heat transfer and sub-grid chemical reaction kinetic model for solid phase combustion of a charring polymer is presented based on distributed reactivity modeling approach. The model is used to compute flammability parameters of a polymer sheet of a given thickness to simulate test results of a cone calorimeter experiment. Comparison of model simulations with cone calorimeter test data shows that

Two-Dimensional Quantum Transport in Free-Standing InSb Nanosheets

Low-dimensional narrow band gap III-V compound semiconductors, such as InAs and InSb, have attracted much attention as one of promising platforms for studying Majorana zero modes and non-Abelian statistics relevant for topological quantum computation. So far, most of experimental studies were performed on hybrid devices based on one-dimensional semiconductor nanowires. In order to build complex to

Physical function tests predict incident falls : A prospective study of 2969 men in the Swedish Osteoporotic Fractures in Men study

Aims: Falls are common in the elderly population, and fall-related injuries are a major health issue. We investigated the ability of simple physical tests to predict incident falls. Methods: The Swedish Osteoporotic Fractures in Men (MrOS) study includes 3014 population-based men aged 69–81 years at the start of the study. These men performed five different physical tests at baseline: right-hand g