What medications are safe and effective for heartburn during pregnancy?

Ranitidine is the best-studied agent effective for treatment of heartburn in pregnancy. Some antacids are effective, but it may be prudent to avoid them in the first trimester until better safety studies are published. Although sucralfate, metoclopromide, and the proton pump inhibitors are probably safe in pregnancy, there are no data about their efficacy. (Grade of Recommendation: B [limited randomized controlled trials of short duration and small sample size]

Estimating net photosynthesis and productivity of a loblolly pine forest grown with carbon dioxide enrichment

I examined the long-term effects of elevated CO2 on the leaf chemistry and photosynthesis of four species growing in the understory and two species growing in the overstory at the Duke Forest FACE experiment. I then used these measurements to parameterize a process based forest productivity model, PnET-II, in order to model the net primary productivity of the portions of the forest growing under ambient and elevated CO2. Finally, I performed a greenhouse study that examined the effects of elevated CO 2 and water availability on the growth and biomass allocation of loblolly pine seedlings from four distinct geographic locations. At the Duke FACE experiment I found a continued stimulation of photosynthesis with elevated CO2 in each species I measured. However the effect of elevated CO2 on photosynthesis of these species did depend on canopy position, season, and year. I observed no CO2-induced changes in leaf chemistry or morphology. Modeled estimates of net primary productivity of the Duke Forest were in good agreement with those measured at the Duke FACE experiment. Estimates of net primary productivity of the portions of the forest grown under elevated CO2 were much greater than the estimates of the portions of the forest grown under ambient CO2. I also found that future climatic conditions expected in North Carolina, USA should alter forest net primary productivity overall but would not alter the response of forest productivity to elevated CO2. In the study of the response of loblolly pine seedlings from different geographic locations to elevated CO2, I found significantly higher biomass in elevated CO2-grown seedlings but I found no evidence of provenance specificity in the growth response to elevated CO2. Decreased water availability did decrease the plant growth and alter biomass allocation irrespective of geographic location and growth CO2 concentration. However, I also concluded that a more detailed analysis is needed with respect to provenance specific responses of loblolly pine to variables of climate change such as CO2 and water availability. Overall my studies revealed that the stimulation of photosynthesis and productivity at the Duke Forest FACE experiment has persisted into the latter years of the experiment and, with no changes in leaf chemistry, no loss of stimulation is expected

Narrow-escape-time problem: the imperfect trapping case

We present a master equation approach to the \emph{narrow escape time} (NET) problem, i.e. the time needed for a particle contained in a confining domain with a single narrow opening, to exit the domain for the first time. We introduce a finite transition probability, $\nu$, at the narrow escape window allowing the study of the imperfect trapping case. Ranging from 0 to $\infty$, $\nu$ allowed the study of both extremes of the trapping process: that of a highly deficient capture, and situations where escape is certain ("perfect trapping" case). We have obtained analytic results for the basic quantity studied in the NET problem, the \emph{mean escape time} (MET), and we have studied its dependence in terms of the transition (desorption) probability over (from) the surface boundary, the confining domain dimensions, and the finite transition probability at the escape window. Particularly we show that the existence of a global minimum in the NET depends on the `imperfection' of the trapping process. In addition to our analytical approach, we have implemented Monte Carlo simulations, finding excellent agreement between the theoretical results and simulations.Comment: 9 page

Automated Fiber Placement Defect Identity Cards: Cause, Anticipation, Existence, Significance, and Progression

Automated Fiber Placement (AFP), a major composite manufacturing process, can result in many defects during the layup process that often require manual corrective action to produce a part with acceptable quality. These defects are the main limitation of the technology and can be hard to categorize or define in many situations. This paper provides a thorough definition and classification of all AFP defects. This effort constitutes a comprehensive and extensive library relevant to AFP defects. The defects selected and defined in this work are based on understanding and experience from the manufacture and research of advanced composite structure. Proper classification of these defects required an in-depth literature review and consideration of various viewpoints ranging from designers, manufacturers, analysts, and inspection professionals. Collectively, these sources were utilized to develop the most accurate view of each of the individual defect types. The results are presented as identity cards for each defect type, intended to provide researchers and the manufacturing industry a clear understanding of the (1) cause, (2) anticipation, (3) existence, (4) significance, and (5) progression of the defined AFP defects. The link between AFP defects and process planning, layup strategies, and machining was also investigated. Categorization of all important automated fiber placement defects is presented

Development of a Model to Predict Intramuscular Fat in Live Pigs Using Real-Time Ultrasound

Recent developments in real-time ultrasound technology offer producers an opportunity to estimate intramuscular fat in live pigs. Genetic improvement of intramuscular fat will continue as an emphasis in swine breeding programs and genetic progress in this important trait will be possible through implementation of this technology

Genetic Parameter Estimates of Production, Meat Quality, and Sensory Traits in Duroc Swine

Heritability estimates detected for carcass composition, meat quality, and sensory measures indicate that improvement in these traits may be attained if adequate selection pressure is applied. Estimates obtained within the current population illustrate that substantial genetic relationships exist between many economically relevant traits. Genetic parameters estimated after 6 generations of selection for intramuscular fat indicate that the use of ultrasound technology may provide a non-invasive method for genetic improvement of IMF and other meat and eating quality components. However, genetic improvement programs aimed at meat quality improvement should be aware of possible adverse effects on carcass leanness, muscling, and loin color

Direct and Correlated Responses to Selection for Intramuscular Fat in Duroc Swine

At the present state of technology, intramuscular fat percentage can be accurately evaluated in live pigs and utilized in conjunction with sib carcass data for estimation of breeding values for intramuscular fat. Within the population under study, selection on resulting EBV has yielded a significant phenotypic change in all measures of IMF. Phenotypic gain in IMF established through selection in the current study resulted in IMF levels that may be useful for differentiation of sire lines for use in muscle quality-based niche markets. Results from this study illustrate that phenotypic improvement of IMF may correspond to an increase in objective tenderness, and shed light into the possible ramifications of this response in measures of carcass composition. Intramuscular fat may be used in swine breeding programs as an indicator of general product palatability; however, sensory characteristic improvements are likely to be slow when simultaneous improvement in other trait categories is also pursued