Assessment of synchrony in multiple neural spike trains using loglinear point process models

Neural spike trains, which are sequences of very brief jumps in voltage across the cell membrane, were one of the motivating applications for the development of point process methodology. Early work required the assumption of stationarity, but contemporary experiments often use time-varying stimuli and produce time-varying neural responses. More recently, many statistical methods have been developed for nonstationary neural point process data. There has also been much interest in identifying synchrony, meaning events across two or more neurons that are nearly simultaneous at the time scale of the recordings. A natural statistical approach is to discretize time, using short time bins, and to introduce loglinear models for dependency among neurons, but previous use of loglinear modeling technology has assumed stationarity. We introduce a succinct yet powerful class of time-varying loglinear models by (a) allowing individual-neuron effects (main effects) to involve time-varying intensities; (b) also allowing the individual-neuron effects to involve autocovariation effects (history effects) due to past spiking, (c) assuming excess synchrony effects (interaction effects) do not depend on history, and (d) assuming all effects vary smoothly across time.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS429 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

A study of longitudinal oscillations of propellant tanks and wave propagations in feed lines. Part II - Wave propagation in elastic pipe filled with incompressible viscous fluid

Fluid wave propagation in liquid propellant feed syste

High fidelity full sized human patient simulation manikins: Effects on decision making skills of nursing students

Background: The continued use of high fidelity full sized human patient simulation manikins (HF-HPSMs) for developing decision making skills of nursing students has led to growing research focusing its value on student learning and decision making skills. Methods: In October 2012, a cross-sectional survey using the 24-item Nurse Decision-Making Instrument was used to explore the decision making process of 232 pre-registration nursing students (age 22.0 + 5.4; 83.2% female) in Singapore. Results: The independent samples t-tests demonstrated three significant predictive indicators. These indicators include: prior experience in high fidelity simulation based on pre-enrolled nursing course (t = 70.6, p = .001), actual hands-on practice (t = 69.66, p < .005) and active participation in debrief (t = 70.11, p < .005). A complete experience based on role-playing followed by active discussion in debrief was a significant contributor to the decision making process (t = 73.6667, p < .005). However, the regression model indicated active participation in debrief as a significant variable which explained its development (t = 12.633, p < .005). Conclusions: This study demonstrated the usefulness of active participation in simulation learning for an analytic- intuitive approach to decision making, however active participation in debrief was a more important influencing element than role-playing. In situations where resources are limited for students to experience hands-on role-playing, peer reviewing and feedback on others’ experiences could benefit students, just as much. However, further study is warranted to determine the development of HF-HPSMs as a pedagogic tool for enhancing the decision making process of nursing students

Expression of the murine cytomegalovirus glycoprotein H by recombinant vaccinia virus

The sequence of the gene encoding glycoprotein H (gH) of murine cytomegalovirus (MCMV) strain Smith was determined and compared with the sequence of the gH of MCMV strain K181. Transcriptional analysis showed that gH is encoded by a large mRNA of 5.0 kb, which is synthesized late in infection. A recombinant vaccinia virus expressing the MCMV gH open reading frame was constructed (Vac-gH). Anti-MCMV serum precipitated a protein of 87K from Vac-gH-infected cells. Reactivity with a monoclonal antibody showed the identity of the MCMV gH with a 87K envelope glycoprotein described previously by Loh and Qualtiere. Immunization of mice with the Vac-gH recombinant gave rise to an anti-gH serum, which neutralized MCMV without complement in vitro

Effect of selected cereal grains on in vitro bioaccessibility of isoflavones in soymilk

Soymilk, which can be called as plant based “milk” is a favourite traditional beverage in Asian with various beneficial health protective effects due to the presence of isoflavones. Mixing cereal grains into soymilk to make a wholesome beverage for breakfast becomes popular. However, dietary factors may affect the bioaccessibility of isoflavones. The aim of this current work was to evaluate changes in the bioaccessibility of isoflavones in soymilk after mixing with selected cereal grains following in vitro gastrointestinal digestion. The samples were subjected to in vitro gastrointestinal digestion with its isoflavones content determined before and after simulated gastric digestion and intestinal digestion with dialysis membrane. Soymilk contained 1.80 ± 0.03 mg daidzein and 2.12 ± 0.08 mg genistein in 100 ml, while bioaccessibility of soymilk daidzein and genistein were 11.24 ± 0.46% and 5.09 ± 0.25% respectively. The addition of cereal grains except barley in soymilk showed significant reduction (p<0.05) in bioaccessibility of isoflavones. Dietary fiber content, especially the insoluble fiber of cereal grains was related to the reduction of bioaccessibility of isoflavones by its entrapping affinity of isoflavones and viscosity effect in the gut. The higher the dietary fiber added into the soymilk, the lower the bioaccessibility of isoflavones in soymilk

The Nature of the H2-Emitting Gas in the Crab Nebula

Understanding how molecules and dust might have formed within a rapidly expanding young supernova remnant is important because of the obvious application to vigorous supernova activity at very high redshift. In previous papers, we found that the H2 emission is often quite strong, correlates with optical low-ionization emission lines, and has a surprisingly high excitation temperature. Here we study Knot 51, a representative, bright example, for which we have available long slit optical and NIR spectra covering emission lines from ionized, neutral, and molecular gas, as well as HST visible and SOAR Telescope NIR narrow-band images. We present a series of CLOUDY simulations to probe the excitation mechanisms, formation processes and dust content in environments that can produce the observed H2 emission. We do not try for an exact match between model and observations given Knot 51's ambiguous geometry. Rather, we aim to explain how the bright H2 emission lines can be formed from within the volume of Knot 51 that also produces the observed optical emission from ionized and neutral gas. Our models that are powered only by the Crab's synchrotron radiation are ruled out because they cannot reproduce the strong, thermal H2 emission. The simulations that come closest to fitting the observations have the core of Knot 51 almost entirely atomic with the H2 emission coming from just a trace molecular component, and in which there is extra heating. In this unusual environment, H2 forms primarily by associative detachment rather than grain catalysis. In this picture, the 55 H2-emitting cores that we have previously catalogued in the Crab have a total mass of about 0.1 M_sun, which is about 5% of the total mass of the system of filaments. We also explore the effect of varying the dust abundance. We discuss possible future observations that could further elucidate the nature of these H2 knots.Comment: 51 pages, 15 figures, accepted for publication in MNRAS, revised Figure 12 results unchange

Shuttle STS-2 mission communication systems RF coverage and performance predictions. Volume 1: Ascent

The RF communications capabilities and nominally expected performance for the ascent phase of the second orbital flight of the shuttle are provided. Predicted performance is given mainly in the form of plots of signal strength versus elapsed mission time for the STDN (downlink) and shuttle orbiter (uplink) receivers for the S-band PM and FM, and UHF systems. Performance of the NAV and landing RF systems is treated for RTLS abort, since in this case the spacecraft will loop around and return to the launch site. NAV and landing RF systems include TACAN, MSBLS, and C-band altimeter. Signal strength plots were produced by a computer program which combines the spacecraft trajectory, antenna patterns, transmit and receive performance characteristics, and system mathematical models. When available, measured spacecraft parameters were used in the predictions; otherwise, specified values were used. Specified ground station parameter values were also used. Thresholds and other criteria on the graphs are explained

Frequently asked questions on measurement of bone mineral densitometry

DXA is a fast, reliable, low-radiation method for assessing BMD, which is the arbiter for osteoporosis treatment eligibility and the best determinant of future fracture risk. • Web-based fracture risk calculators can utilise BMD data to provide further information for medical practitioners and patients. • The interval for serial BMD assessment for detecting development of osteoporosis should be planned according to the previous DXA findings