The effect of portacaval transposition on carbohydrate metabolism: Experimental and clinical observations

An investigation was conducted of the influence of portacaval transposition upon carbohydrate metabolism in 45 dogs. In 17 dogs, hepatic glycogen content was measured before and from 45 to 75 days after transposition. A reduction in glycogen content, principally in the TCA soluble fraction, was noted in 14 animals. The mean loss of total glycogen was 51 percent, and the mean loss of TCA soluble glycogen was 70 percent. In control animals hepatic deglycogenation did not occur. Despite the reduction in hepatic glycogen content, the animals were capable of glucagon-induced glycogenolysis using very small test doses. After transposition, a greater response to intraportal injection was noted as compared to that obtained with systemic venous infusions. Other alterations in carbohydrate metabolism were also measured. These included a reduction in the duration and magnitude of the hyperglycemic response to oral glucose loads. The profile of glycemic response under these conditions was studied, and demonstrated to be greatest in the portal vein, least in the peripheral venous blood, and of intermediate magnitude in the peripheral arteries. Based upon the hepatic deglycogenating effect of portacaval transposition in dogs, this operation was used for the treatment of an 8 1 2-year-old child with glycogen storage disease and concomitant portal cirrhosis. The portacaval transposition was performed in preference to a standard portacaval shunt. The enzyme defect in the patient was extensively studied before and after transposition. Prior to surgery, she was demonstrated to have Type IIIB glycogenosis (amylo-1,6-glucosidase deficiency confined to the liver). Eight and one half months after operation, the quantities of glycogen in liver and muscle and the enzyme activities showed no significant alteration. The clinical response to portacaval transposition was gratifying. There has been a decrease in the hepatosplenomegaly, rapid growth, a diminution in the pre-existing hypersplenism, and a considerable increase in the child's physical activity. Most of these benefits are ascribable to the effective portal decompressive procedure. Whether any metabolic benefit derived from the portacaval transposition is problematical. © 1965

Selected reliability studies for the NERVA program

An investigation was made into certain methods of reliability analysis that are particularly suitable for complex mechanisms or systems in which there are many interactions. The methods developed were intended to assist in the design of such mechanisms, especially for analysis of failure sensitivity to parameter variations and for estimating reliability where extensive and meaningful life testing is not feasible. The system is modeled by a network of interconnected nodes. Each node is a state or mode of operation, or is an input or output node, and the branches are interactions. The network, with its probabilistic and time-dependent paths is also analyzed for reliability and failure modes by a Monte Carlo, computerized simulation of system performance

You Have Got Me Guessing

https://digitalcommons.library.umaine.edu/mmb-vp/3454/thumbnail.jp

Adaptive Step Size for Hybrid Monte Carlo Algorithm

We implement an adaptive step size method for the Hybrid Monte Carlo a lgorithm. The adaptive step size is given by solving a symmetric error equation. An integr ator with such an adaptive step size is reversible. Although we observe appreciable variations of the step size, the overhead of the method exceeds its benefits. We propose an explanation for this phenomenon.Comment: 13 pages, 5 Postscript figures, late

Towards Reverse Engineering of PDF Documents

summary:We present a progress report on our ongoing project of reverse engineering scientific PDF documents. The aim is to obtain mathematical markup that can be used as source for regenerating a document that resembles the original as closely as possible. This source can then be a basis for further document processing. Our current tool uses specialised PDF extraction together with image analysis to produce near perfect input for parsing mathematical formula. Applying a linear grammar and specific drivers for each output format to this input, we can produce an accurate reproduction of formulae when presented with their coordinates. In this paper we will show how this information can be exploited to discover the locations of both inline and display formulae, and also to perform rudimentary layout analysis of the whole document, identifying structures such as headings and paragraphs

An Atypical Case of Polioencephalomalicia

Polioencephalomalacia (PEM) is a significant feedlot cattle problem here in the midwest. Differentiation of this disease from other diseases that produce central nervous signs such as acute lead poisoning (ALP), thromboembolic meningoencephalomyelitis, hypomagnesemia, and rabies is important to the practitioner as he has to decide on the best course of therapy for recovery

Spatial Analysis of County-Level Breast Cancer Mortality in Texas

Objective. The objectives of the study were to detect high-risk areas and to examine how racial and ethnic status affect the geographic distribution of female breast cancer mortality in Texas. Analyses were based on county-level data for the years from 2000 to 2008. Materials and Methods. Breast cancer mortality data were obtained from the Texas Cancer Registry, and the Spatial Scan Statistics method was used to run Purely Spatial Analyses using the Discrete Poisson, Bernoulli, and Multinomial models. Results and Conclusions. Highest rates of female breast cancer mortality in Texas have shifted over time from southeastern areas towards northern and eastern areas, and breast cancer mortality at the county level is distributed heterogeneously based on racial/ethnic status. Non-Hispanic blacks were at highest risk in the northeastern region and lowest risk in the southern region, while Hispanics were at highest risk in the southern region along the border with Mexico and lowest risk in the northeastern region

Insensitivity of alkenone carbon isotopes to atmospheric CO₂ at low to moderate CO₂ levels

Atmospheric pCO2 is a critical component of the global carbon system and is considered to be the major control of Earth’s past, present and future climate. Accurate and precise reconstructions of its concentration through geological time are, therefore, crucial to our understanding of the Earth system. Ice core records document pCO2 for the past 800 kyrs, but at no point during this interval were CO2 levels higher than today. Interpretation of older pCO2 has been hampered by discrepancies during some time intervals between two of the main ocean-based proxy methods used to reconstruct pCO2: the carbon isotope fractionation that occurs during photosynthesis as recorded by haptophyte biomarkers (alkenones) and the boron isotope composition (δ11B) of foraminifer shells. Here we present alkenone and δ11B-based pCO2 reconstructions generated from the same samples from the Plio-Pleistocene at ODP Site 999 across a glacial-interglacial cycle. We find a muted response to pCO2 in the alkenone record compared to contemporaneous ice core and δ11B records, suggesting caution in the interpretation of alkenone-based records at low pCO2 levels. This is possibly caused by the physiology of CO2 uptake in the haptophytes. Our new understanding resolves some of the inconsistencies between the proxies and highlights that caution may be required when interpreting alkenone-based reconstructions of pCO2

Small area estimation strategy for the 2011 Census in England and Wales

© 2018-IOS Press and the authors. All rights reserved. The use of model-based small area estimation for adjusting census results in the UK was first introduced in the 2001 Census. The aim was to obtain local level population estimates by age-sex groups, adjusted for the level of undercount that combined results from the Census and the Census Coverage Survey. A similar approach was adopted for the 2011 Census but with new features and this paper describes the work carried out to arrive at the chosen small area strategy. Simulation studies are used to investigate three proposed small area estimation methods: a local fixed effects model (the 2001 Census approach), a direct estimator and a synthetic estimator. The results indicate that both the synthetic and the local fixed effect models constitute good options to produce accurate and reliable local authority population estimates. A proposal is made to implement a small area estimation procedure that accommodates both the synthetic and local fixed models, as in some selected areas with differing local authority under-coverage rates a local fixed effects model may perform best. We examine this strategy under real census conditions based on the final results from the 2011 census

Use of practice tracks in the medical specialties.

OBJECTIVES: To evaluate the use of practice tracks by each of the 24 medical specialty boards and to compare this with the experience in emergency medicine (EM). METHODS: Scripted telephone surveys were conducted with representatives of each of the specialty boards. RESULTS: Of 24 specialties currently recognized by the American Board of Medical Specialties (ABMS), 14 (58%) reported a history of a practice track. Eight boards reported never having a practice track and 2 were unsure. All practice tracks have been limited in duration, most commonly closing after a specified period. The mean duration of the practice tracks was 9.8 years, the median was 7.5 years, and the range was 3-27 years. The practice track in EM was open for 9 years. CONCLUSIONS: Practice tracks were common in the early years of most specialties and most were limited by duration. The history of the practice track in EM is not dissimilar to those of other specialties