Effects of Pain on Functioning and Well-Being in Older Adults With Osteoarthritis of the Knee.

The effects of pain on functioning and well-being were examined in 367 older adults with osteoarthritis (OA) of the knee. The relationship of OA-related pain to depressive symptoms and perceived health was hypothesized to be direct as well as mediated by physical and social functioning. Results showed that OA-related pain was related to poorer physical and social functioning, had a direct effect on depressive symptoms, and direct and indirect effects on perceived health. Lower social functioning was related to more depressive symptoms, and both lower social and physical functioning predicted worse perceived health. Thus, distinguishing between physical and social functioning when examining the costs of OA-related pain is useful. Moreover, existing pain-psychological well-being models can be generalized to perceived health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparative accuracy of glucose monitors

The objective of this study was to rationalize the shape of membrane permeability-lipophilicity curves, when considering, in addition to the usual transcellular route, a parallel diffusion pathway through aqueous pores as present in biological membranes. The theoretical influence of different pH in donor and acceptor compartment and the molecular weight on the permeability curves was studied. We combined and extended two previously proposed absorption models, namely one describing diffusion through a simple membrane (two stagnant aqueous and two organic layers in series, no pores) as the sum of the two distribution steps at both membrane interfaces, and a second theoretical model considering the sum of different diffusional resistances through stagnant layers and membrane, respectively. Under certain conditions the equivalence of the two-step distribution model and the diffusional resistance model can be demonstrated. Incorporation of an aqueous diffusion pathway leads to an extended two-step distribution model. This theoretical membrane permeation model will permit a more physicochemical-based interpretation of permeation data and shows that combined log D values and molecular weight are important determinants for membrane transport processes through, e.g. Caco-2 monolayers and the mucosal GI membranes. We have demonstrated that the well-known sigmoidal permeability-lipophilicity relationship should be considered as a molecular weight-dependent set of sigmoidal relationships.     

Assessing the developmental components of managerial jobs.

Describes the development of and builds validity evidence for the Developmental Challenge Profile (DCP), an instrument for assessing the developmental components of managerial jobs. Factor analysis of responses from 692 managers resulted in the creation of 15 DCP scales. Assessments of internal consistency, confirmation of the factor structure, and test-retest reliability provided further psychometric support for the scales. The existence of expected relationships between the scales and reports of on-the-job learning, job transitions, objective features of the jobs, and psychological states of the job incumbents provided validity evidence and supported use of these scales in management development research and applications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Countercontrol treatment of sleep-maintenance insomnia in relation to age.

Administered countercontrol behavioral therapy for sleep-maintenance insomnia to 34 insomniacs (aged 35–78 yrs) in small groups. 22 Ss received immediate and 12 received delayed treatment. Three self-report measures of sleep disruption were collected on daily sleep diaries at baseline, termination of treatment, 1-mo follow-up, and 12-mo follow-up. Although amount of time awake at night was correlated with age, response to treatment was not. Even though older Ss experienced more time awake after sleep onset prior to treatment, they were able to profit from therapy as well as the younger insomniacs. Countercontrol therapy reduced the sleep complaint for the total group by about 30% at the end of treatment, with gradual improvement continuing through a 4-wk follow-up. It is suggested, however, that sleep-maintenance insomnia may be more difficult to treat than sleep-onset problems. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference between phonemes during monitoring: Evidence for an interactive activation model of speech perception.

Explored the finding by J. E. Newman and G. S. Dell (see record 1981-00233-001) that the time needed to detect a target phoneme in a phoneme monitoring task increased when the preceding word contained a phoneme similar to the target. In 3 experiments, 58 undergraduates who were native speakers of English monitored auditorily presented sentences and responded as quickly as possible whenever they detected a specified phoneme. Preceding word-initial phonemes, despite being processed more quickly, increased the response latency to the following target phoneme more than did preceding word-medial phonemes. There was also an increase in response latency even when the S could be highly certain that the similar preceding phoneme was not an instance of the target phoneme. It is argued that the interference effects are due to fundamental characteristics of perceptual processing and that more time is needed to categorize the target phoneme. A computer simulation using an interactive activation model of speech perception is presented to demonstrate the plausibility of this explanation. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Application of the USGS diffusion hydrodynamic model (DHM) in evaluation of estuary flow circulation

Many of the hydrodynamic models used for tidal flow regime and storm surge analysis are based upon use of the two-dimensional hydrodynamic equations, which are obtained from the parent three-dimensional flow equations by averaging with respect to the vertical coordinates. Various numerical techniques, such as finite difference, finite element, and the method of characteristics have been used to solve these mathematical models.

The USGS diffusion hydrodynamic model has been developed to simulate two-dimensional surface water flows, and solves the governing flow equations by neglecting the inertia terms. The DHM has previously been applied to a hypothetical bay study with results comparable to those obtained using the method of characteristics. In the current work, the DHM is applied to the Batiquitos Lagoon located in the City of Encinitas, California for the purposes of evaluation of tidal flow characteristics. The main objective is to determine local flow velocities and circulation patterns in the lagoon caused by the incoming and outgoing tide.     

Wave exposure and hydrologic connectivity create diversity in habitat and zooplankton assemblages at nearshore Long Point Bay,Lake Erie

During an 11-day period in August 2008, we visited 102 sites along the nearshore (~ 60 km) of Long Point Bay. The purpose of our study was to evaluate the effects of wave exposure and hydrologic connectivity on zooplankton distributions. Long Point is located within the UNESCO Long Point Biosphere Reserve (26,250 ha) and encompasses the largest wetland complex in the Great Lakes system. We sampled for zooplankton, aquatic vegetation, temperature, specific conductance, pH, dissolved oxygen, dissolved organic carbon, water clarity, total nitrogen and depth. We evaluated the impacts of exposure using wind and fetch data to calculate a Relative Exposure Index (REI). Ordination techniques revealed a large variation in physical disturbance, water clarity, nutrient concentrations, water chemistry and aquatic vegetation that explained the distribution pattern of zooplankton at the 102 sites. Gradients of REI are strongly positively correlated with environmental variables, such as pH, dissolved oxygen and temperature and highly negatively correlated with conductivity and dissolved organic carbon. Visual inspection of the ordination site scores revealed the 102 sites clustering into six main groups based on spatial location and degree of surface-water connectivity to Long Point Bay. Sheltered sites (low REI) have much higher abundance of zooplankton whereas sites that have high REI scores are characterized by relatively low zooplankton abundance with a high prevalence of Polyarthra sp. This is the largest study on the distribution pattern of zooplankton in Long Point Bay, and it highlights the importance of wave exposure and hydrologic connectivity in structuring the zooplankton community.     

Synthesis and alteration of α-LiFeO2 by mechanochemical processes

The effects of grinding on a stoichiometric mixture of LiOH · H₂O and -FeOOH were studied. It was found that, in the course of grinding, losses of structural water occurred and a phase structurally related to disordered -LiFeO₂ was formed. X-ray diffraction data suggest the occurrence of an ordered phase as intermediate and both -Fe₂O₃ and -Fe₂O₃ were undetected during the comminution process. A prolonged mechanical treatment of this mixture originated an elimination of Li⁺ from the -LiFeO₂ structure and the appearance of the spinel phase, -LiFe₅O₈. Additionally, the mechanical activation of a sample of -LiFeO₂ prepared at high temperatures also leads to a similar rearrangement of cations. The structural transformation is explained with the help of a model in which the vacancies of Li⁺ created during grinding promote the migration of the Fe³⁺ ions from octahedral to tetrahedral sites.     

Protonation of Nucleobases in Single‐ and Double‐Stranded DNA

Single‐stranded model oligodeoxyribonucleotides, each containing a single protonatable base—cytosine, adenine, guanine, or 5‐methylcytosine—centrally located in a background of non‐protonatable thymine residues, were acid‐titrated in aqueous solution, with UV monitoring. The basicity of the central base was shown to depend on the type of the central base and its nearest neighbours and to rise with increasing oligonucleotide length and decreasing ionic strength of the solution. More complex model oligonucleotides, each containing a centrally located 5‐methylcytosine base, were comparatively evaluated in single‐stranded and double‐stranded form, by UV spectroscopy and high‐field NMR. The N³ protonation of the 5‐methylcytosine moiety in the double‐stranded case occurred at much lower pH, at which the duplex was already experiencing general dissociation, than in the single‐stranded case. The central guanine:5‐methylcytosine base pair remained intact up to this point, possibly due to an unusual alternative protonation on O² of the 5‐methylcytosine moiety, already taking place at neutral or weakly basic pH, as indicated by UV spectroscopy, thus suggesting that 5‐methylcytosine sites in double‐stranded DNA might be protonated to a significant extent under physiological conditions.