We describe a simple multiplex vibrational spectroscopic imaging technique based on employing chirped femtosecond pulses in a coherent anti-Stokes Raman scattering (CARS) scheme. Overlap of a ...femtosecond Stokes pulse with chirped pump/probe pulses introduces a temporal gate that defines the spectral resolution of the technique, allowing single-shot acquisition of high spectral resolution CARS spectra over a several hundred wavenumber bandwidth. Simulated chirped (c-) CARS spectra match the experimental results, quantifying the dependence of the high spectral resolution on the properties of the chirped pulse. c-CARS spectromicroscopy offers promise as a simple and generally applicable high spatial resolution, chemically specific imaging technique for studying complex biological and materials samples.
The Cystic Fibrosis Questionnaire (CFQ) is a disease-specific instrument that measures health-related quality of life (HRQOL) for adolescents and adults with cystic fibrosis (CF) > or = 14 years, ...consisting of 44 items on 12 generic and disease-specific scales. Versions of the CFQ are also available for children with CF and their parents. This study evaluated the psychometric properties of the CFQ in a national study at 18 CF centers in the United States.
The CFQ-teen/adult was administered to 212 patients with CF ranging in age from 14 to 53 years. Test-retest reliability was assessed in a subset of patients over a 10- to 14-day interval.
Multitrait analysis indicated a majority of items (95%) correlated more highly with their intended scale than a competing scale, supporting the conceptual model. Internal consistency coefficients indicated the CFQ scales had good reliability (Cronbach alpha = 0.67 to 0.94), and test-retest stability was acceptable (rs = 0.45 to 0.90). Validity was demonstrated by examining relationships between the CFQ, age, pulmonary function, and body mass index. As expected, the CFQ was inversely correlated with age, with older adults reporting lower CFQ scores than younger adults, better nutritional status was positively correlated with several weight-related scales, and the measure differentiated between individuals with varying levels of disease severity. Strong associations were also found between the CFQ and similar scales on the Short Form-36 Health Questionnaire, a well-known generic HRQOL measure.
The results demonstrated that the CFQ-teen/adult is a reliable and valid measure of HRQOL for individuals with CF. It may be utilized in clinical trials to assess the effects of new therapies, to document the progression of disease, and to inform clinical practice.
X-ray absorption spectra of aqueous 4 and 6 M potassium hydroxide solutions have been measured near the oxygen K edge. Upon addition of KOH to water, a new spectral feature (532.5 eV) emerges at ...energies well below the liquid water pre-edge feature (535 eV) and is attributed to OH- ions. In addition to spectral changes explicitly due to absorption by solvated OH- ions, calculated XA spectra indicate that first-solvation-shell water molecules exhibit an absorption spectrum that is unique from that of bulk liquid water. It is suggested that this spectral change results primarily from direct electronic perturbation of the unoccupied molecular orbitals of first-shell water molecules and only secondarily from geometric distortion of the local hydrogen bond network within the first hydration shell. Both the experimental and the calculated XA spectra indicate that the nature of the interaction between the OH- ion and the solvating water molecules is fundamentally different than the corresponding interactions of aqueous halide anions with respect to this direct orbital distortion. Analysis of the Mulliken charge populations suggests that the origin of this difference is a disparity in the charge asymmetry between the hydrogen atoms of the solvating water molecules. The charge asymmetry is induced both by electric field effects due to the presence of the anion and by charge transfer from the respective ions. The computational results also indicate that the OH- ion exists with a predominately “hyper-coordinated” solvation shell and that the OH- ion does not readily donate hydrogen bonds to the surrounding water molecules.
Neutral and acidic oligosaccharides were isolated from the milk or colostrum of four great ape species (chimpanzee (Pan troglodytes), bonobo (Pan paniscus), gorilla (Gorilla gorilla), and orangutan ...(Pongo pygmaeus)) and one lesser ape species (siamang (Symphalangus syndactylus)), and their chemical structures were characterized by 1H-NMR spectroscopy. Oligosaccharides containing the type II unit (Gal(β1-4)GlcNAc) were found exclusively (gorilla and siamang) or predominately (chimpanzee, bonobo, and orangutan) over those containing the type I unit (Gal(β1-3)GlcNAc). In comparison, type I oligosaccharides predominate over type II oligosaccharides in human milk, whereas nonprimate milk almost always contains only type II oligosaccharides. The milk or colostrum of the great apes contained oligosaccharides bearing both N-glycolylneuraminic acid and N-acetylneuraminic acid, whereas human milk contains only the latter. Great ape milk, like that of humans, contained fucosylated oligosaccharides whereas siamang milk did not. Since these analyses are based on a limited number of individuals, further research on additional samples of great and lesser ape milk is needed to confirm phylogenetic patterns.
Suprascapular nerve entrapment Cummins, C A; Messer, T M; Nuber, G W
Journal of bone and joint surgery. American volume,
03/2000, Letnik:
82, Številka:
3
Journal Article
Studies of race riots have identified several underlying conditions that contribute to their onset. This study builds on previous research and introduces an integrative approach for examining riots ...that includes the role of population characteristics, contextual factors, and cultural ideologies. An integrative approach is applied through a case study of the 1921 Tulsa Race Riot. In addition to highlighting relevant structural and contextual under pinnings, this approach also emphasizes the role of racial frames, or lenses through which racial groups view and interpret events and conditions differenctially.
People frequently overestimate their understanding-with a particularly large blind-spot for gaps in their causal knowledge. We introduce a metacognitive approach to reducing overestimation, termed ...reflecting on explanatory ability (REA), which is briefly thinking about how well one could explain something in a mechanistic, step-by-step, causally connected manner. Nine experiments demonstrated that engaging in REA just before estimating one's understanding substantially reduced overestimation. Moreover, REA reduced overestimation with nearly the same potency as generating full explanations, but did so 20 times faster (although only for high complexity objects). REA substantially reduced overestimation by inducing participants to quickly evaluate an object's inherent causal complexity (Experiments 4-7). REA reduced overestimation by also fostering step-by-step, causally connected processing (Experiments 2 and 3). Alternative explanations for REA's effects were ruled out including a general conservatism account (Experiments 4 and 5) and a covert explanation account (Experiment 8). REA's overestimation-reduction effect generalized beyond objects (Experiments 1-8) to sociopolitical policies (Experiment 9). REA efficiently detects gaps in our causal knowledge with implications for improving self-directed learning, enhancing self-insight into vocational and academic abilities, and even reducing extremist attitudes.
The oxygen K edge X-ray absorption spectra of aqueous HCl and NaCl solutions reveal distinct perturbations of the local water molecules by the respective solutes. While the addition of NaCl leads to ...large spectral changes, the effect of HCl on the observed X-ray absorption spectrum is surprisingly small. Density functional theory calculations suggest that this difference primarily reflects a strong blue shift of the hydrated proton (in either the Eigen (H9O4 +) or Zundel (H2O5 +) forms) spectrum relative to that of H2O, indicating the tighter binding of electrons in H3O+. This spectral shift counteracts the spectral changes that arise from direct electrostatic perturbation of water molecules in the first solvation shell of Cl-. Consequently, the observed spectral changes effected by HCl addition are minimal compared to those engendered by NaCl. Additionally, these results indicate that the effect of monovalent cations on the nature of the unoccupied orbitals of water molecules in the first solvation shell is negligible, in contrast to the large effects of monovalent anions.
PDF
