7,876 research outputs found
Somatic Pairing in Drosophila virilis Mitosis
In neuroblast cells homologous chromosomes tend to pair during prophase of mitosis. Heterochromatic elements of homologous chromosomes are widely separated in very early prophase, at which time the euchromatin is poorly stained. Pairing is intimate for euchromatic portions of chromosomes in early and middle prophase with chiasmata frequently present. Homologous chromosomes most commonly lie side-by-side in late prophase and metaphase. Statistical data are presented to show the frequency of intimate pairing in prophase and side by side pairing in metaphase
CDCCRAY
The CDCCRAY is a FORTRAN subroutine which runs on the Cray and converts 32 or 64 bit binary data from the CDC Cyber 205 to the corresponding 64 bit binary data for the Cray X-MP. The CDCCRAY's purpose, usage, storage, timing consideration, and linkage editing are discussed
Quantitative absorption and fluorescence study of CO from 1060 to 1550 A
Measurement of the photoabsorption cross section of CO in the 1060-1550 A region using synchrotron radiation is described. The oscillator strengths for the transitions from CO (Chi1Sigma+ to various excited states are obtained from these data. Fluorescence from excited CO was observed in the 1150 to 3000 A and 3000 to 8000 A regions. The quantum yields for the production of fluroescence from the Alpha(1)P and B(1)Sigma(+) states are unity because their excitation energies are below the dissociation limit. The C(1)Sigma(+) , v = O level has significant fluorescence quantum yields both in the UV and visible region, but the yields for the E(1)Pi, v = O and C(1)Sigma(+), v = 1 levels are very small. The C(1)Sigma(+), v = 1 level is presumably predissociated. The cross sections for the production of fluroescence from the a'(3)Sigma(+), d(3)Delta sub 1, e(3)Sigma(-) yields a(3)Pi, and B(1)Sigma(+), C(1)Sigma(+) yields A(1)Pi transitions upon excitation from the X(1)Sigma(+) were measured
The role of psychological distance in value creation
Purpose – The field of service research has devoted consider able attention to the customer's role as value creator, but there is a lack of research on understanding customers' psychological processes in value creation. This paper highlights the importance of psychological distance in value-creation processes. Psychological distance is the customer's perceived distance from service interactions in terms of spatial distance, temporal distance social distance and hypothetical distance. Critically, psychological distance influences cognitive processes and can influence how customers think and feel about the service interaction. An appreciation of psychological distance within service contexts can help managers to tailor the interaction in order to facilitate value creation. Methodology/approach – In this conceptual paper, we build on psychology research and service research to develop seven propositions that explore how psychological distance can operate within service interactions and how this might influence value creation. Findings – We divide the propositions into three sections. The first concerns how perceived psychological distance from the service interaction can act as a barrier to entering a service interaction. In particular, we consider the influence of social distance and spatial distance within the context of service interactions. The second section examines how psychological distance to the expected point of service use can influence how customers construe the service and the value creation. The third aspect addresses customer-specific characteristics that can impact on value creation by influencing perceived psychological distance toward the service
Solutions Network Formulation Report. Improving NOAA's Tides and Currents Through Enhanced Data Inputs from NASA's Ocean Surface Topography Mission
The Nation uses water-level data for a variety of practical purposes, including hydrography, nautical charting, maritime navigation, coastal engineering, and tsunami and storm surge warnings (NOAA, 2002; Digby et al., 1999). Long-term applications include marine boundary determinations, tidal predictions, sea-level trend monitoring, oceanographic research, and climate research. Accurate and timely information concerning sea-level height, tide, and ocean current is needed to understand their impact on coastal management, disaster management, and public health. Satellite altimeter data products are currently used by hundreds of researchers and operational users to monitor ocean circulation and to improve scientists understanding of the role of the oceans in climate and weather. The NOAA (National Oceanic and Atmospheric Administration) National Ocean Service has been monitoring sea-level variations for many years (NOAA, 2006). NOAA s Tides & Currents DST (decision support tool, managed by the Center for Operational Oceanographic Products and Services, is the portal to a vast collection of oceanographic and meteorological data (historical and real-time), predictions, and nowcasts and forecasts. This report assesses the capacity of NASA s satellite altimeter data to meet societal decision support needs through incorporation into NOAA s Tides & Currents
Quantitative absorption and fluorescence studies of NO between 1060 and 2000 A
Synchrotron radiation in the 1060 to 2000 A region was used to measure the average absorption and fluorescence cross sections of NO and to determine approximate photodissociation quantum yields. Several vibrational levels of the D(2) sigma(+), E(2) sigma(+), and B(2) delta states have high fluorescence quantum yields. The C(2) and B(2) states do not fluoresce when the excitation energies are above the first dissociation limit, in accord with previous experiments. In general, the fluorescence yields decrease with increasing photon energy. The quantitative measurements are compared with spectroscopic observations and are found to be reasonably consistent
Improving NOAA's NWLON Through Enhanced Data Inputs from NASA's Ocean Surface Topography
This report assesses the benefit of incorporating NASA's OSTM (Ocean Surface Topography Mission) altimeter data (C- and Ku-band) into NOAA's (National Oceanic and Atmospheric Administration) NWLON (National Water Level Observation Network) DSS (Decision Support System). This data will enhance the NWLON DSS by providing additional inforrnation because not all stations collect all meteorological parameters (sea-surface height, ocean tides, wave height, and wind speed over waves). OSTM will also provide data where NWLON stations are not present. OSTM will provide data on seasurface heights for determining sea-level rise and ocean circulation. Researchers and operational users currently use satellite altimeter data products with the GSFCOO NASA data model to obtain sea-surface height and ocean circulation inforrnation. Accurate and tirnely inforrnation concerning sea-level height, tide, and ocean currents is needed to irnprove coastal tidal predictions, tsunarni and storm surge warnings, and wetland restoration
The relative importance of perceptual and memory sampling processes in determining the time course of absolute identification
In absolute identification, the EGCM–RT (Kent & Lamberts, 2005, 2016) proposes that perceptual processing determines systematic response time (RT) variability; all
other models of RT emphasise response selection rocesses. In the EGCM-RT the bow effect in RTs (longer responses for stimuli in the middle of the range) occurs because these middle stimuli are less isolated and so as perceptual information is accumulated, the evidence supporting a correct response grows more slowly than for
stimuli at the ends of the range. More perceptual information is therefore accumulated in order to increase certainty in response for middle stimuli, lengthening RT.
According to the model reducing perceptual sampling time should reduce the size of the bow effect in RT. We tested this hypothesis in two pitch identification experiments. Experiment 1 found no effect of stimulus duration on the size of the RT bow. Experiment 2 used multiple short stimulus durations as well as manipulating set size and stimulus spacing. Contrary to EGCM-RT predictions, the bow effect on RTs was large for even very short durations. A new version of the EGCM-RT could only
capture this, alongside the effect of stimulus duration on accuracy, by including both a perceptual and a memory sampling process. A modified version of the SAMBA
model (Brown, Marley, Donkin, & Heathcote, 2008) could also capture the data, by assuming psychophysical noise diminishes with increased exposure duration. This
modelling suggests systematic variability in RT in absolute identification is largely determined by memory sampling and response selection processes
A qualitative study in rural and urban areas on whether - and how - to consult during routine and out of hours
Peer reviewedPublisher PD
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