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The Milky Way hosts on average a few supernova explosions per century, yet in the past millennium only five supernovae have been identified confidently in the historical record. This deficit of naked-eye supernovae is at least partly due to dust extinction in the Galactic plane. We explore this effect quantitatively, developing a formalism for the supernova probability distribution in space and on the sky, accounting for dust and for the observer's flux limit. We then construct a fiducial axisymmetric model for the spatial supernova and dust densities, featuring an exponential dependence on galactocentric radius and height, with core-collapse events in a thin disc and Type Ia events including a thick disc component. When no flux limit is applied, our model predicts that on the sky, supernovae are intrinsically concentrated in the Galactic plane, with Type Ia events extending to higher latitudes. We then apply a flux limit and include dust effects, to predict the sky distribution of historical supernovae. We use well-observed supernovae as light-curve templates, and introduce naked-eye discovery criteria. The resulting sky distributions are strikingly inconsistent with the locations of confident historical supernovae, none of which lie near our model's central peaks. Indeed, SN 1054 lies off the plane almost exactly in the anticentre, and SN 1181 is in the second Galactic quadrant. We discuss possible explanations for these discrepancies. We calculate the percentage of all supernovae bright enough for historical discovery: |$\simeq 13{{\ \rm per\ cent}}$| of core-collapse and |$\simeq 33{{\ \rm per\ cent}}$| of Type Ia events. Using these and the confident historical supernovae, we estimate the intrinsic Galactic supernova rates, finding general agreement with other methods. Finally, we urge searches for supernovae in historical records from civilizations in the Southern hemisphere. [ABSTRACT FROM AUTHOR]

Objective:To examine the interaction of the cytokines interleukin-1 receptor antagonist (IL)-1Ra, IL-6 and IL-10 to predict preterm birth (PTB) in pregnant Hispanic women (n=470).Study Design:In this prospective study, demographic data were obtained prenatally and birth outcome data were obtained from the medical chart. Cytokines were measured from plasma obtained at 22 to 24 weeks gestation. Data analysis utilized logistic regression.Result:PTB was predicted by level of IL-1Ra (odds ratio (OR)=2.55; 95% confidence interval (CI)=1.24, 5.24). The interaction between IL-1Ra and IL-6 and between IL-1Ra and IL-10 was significant (Wald=4.01, P=0.04 and Wald=8.84, P<0.003, respectively) and was also predictive of PTB. As IL-1Ra levels increased while IL-10 levels were low, the probability of PTB greatly increased.Conclusion:The interactions of select cytokines and cytokine receptor antagonists were associated with PTB. Future research should focus on the changes in cytokines during pregnancy to identify critical periods of change, and examine predictors of the cytokine response. [ABSTRACT FROM AUTHOR]

Introduction: The objectives of this study were to collect preliminary data related to self-reported dental problems, dental health–related nutrient intake, and acidogenic meal and snack composition intake during early pregnancy in low-income women and to assess the feasibility of current research methods for use in a larger study. Methods: Low-income women (n = 13) in the first trimester of pregnancy participated in this study. Pregnant women completed a demographic questionnaire, participated in three 24-hour dietary recalls, and answered several questions related to their oral health status and frequency of dental visits. Results: Preliminary data suggest that women in this study were susceptible to dental problems and consumed acidogenic meals and snacks. Protocol data suggest that it is feasible to implement current research protocols, with adaptations, for use in a larger study. Discussion: Health care professionals should assess low-income pregnant women in early pregnancy for dental problems and acidogenic meal and snack patterns and provide referrals to appropriate health professionals and community health services. [ABSTRACT FROM AUTHOR]

A pilot study was conducted to explore the dietary quality and maternal psychosocial status during the early weeks of pregnancy in a convenience sample of women (N = 13) recruited from two Planned Parenthood Clinics. Women were between 19 and 31 years of age, having their first pregnancy, and were on average 7 weeks pregnant. Average caloric intake was 2653 kcal/day consisting of 34% fat. Six of the women had inadequate intake of calcium (x = 800 mg) and 11 had low iron intake (x = 20 mg). Dietary Quality Index-Pregnancy scores were below recommendations and six women had scores indicating a major depression. Dietary intakes of these low-income women early in pregnancy did not meet recommendations for pregnancy. Identifying factors that are related to poor dietary intake, such as low-income and the presence of depression, in early pregnancy may promote timely recognition of women in need of comprehensive monitoring throughout the pregnancy. [ABSTRACT FROM AUTHOR]

With the advancement in computer technology, it has become possible to fit complex models to neuronal data. In this work, we test how two methods can estimate parameters of simple neuron models (passive soma) to more complex ones (neuron with one dendritic cylinder and two active conductances). The first method uses classical voltage traces resulting from current pulses injection (time domain), while the second uses measures of the neuron's response to sinusoidal stimuli (frequency domain). Both methods estimate correctly the parameters in all cases studied. However, the time-domain method is slower and more prone to estimation errors in the cable parameters than the frequency-domain method. Because with noisy data the goodness of fit does not distinguish between different solutions, we suggest that running the estimation procedure a large number of times might help find a good solution and can provide information about the interactions between parameters. Also, because the formulation used for the model's response in the frequency domain is analytical, one can derive a local sensitivity analysis for each parameter. This analysis indicates how well a parameter is likely to be estimated and helps choose an optimal stimulation protocol. Finally, the tests suggest a strategy for fitting single-cell models using the two methods examined. [ABSTRACT FROM AUTHOR]

Disintegration of cottonseed meats is an important unit operation in the cottonseed fractionation process. The results of tests utilizing a high-speed, 'dissolver-type' impeller for disintegration by liquid shear are presented including curves to show the effect of moisture, hulls, solvents, peripheral speed, etc. Over 90% of through-80-mesh material can be obtained. Moisture content over 5% appreciably reduced the efficiency and increased power consumption and the viscosity of the slurry. Whole flakes resulted in a finer end product than flakes pre-pulverized in the dry state. It was found that the presence of hulls slightly increased disintegration, power consumption, and viscosity; that higher speeds (up to 6,000 FPM peripheral speed) were more efficient; and that the effect of solvents was small. [ABSTRACT FROM AUTHOR]