Over 90 million Americans suffer from Nonalcoholic Fatty Liver Disease (NAFLD), characterized by excessive liver fat and chronic inflammation. This may progress to nonalcoholic steatosis hepatitis (NASH), liver cirrhosis and hepatocellular carcinoma. Blood lipid metabolic disorders, dyslipidemia, are common in patients with NAFLD. The majority of tracer kinetic studies of apolipoprotein particle metabolism have required in-patient IV tracer administration. Our objective was to develop a simple, safe and clinically useful approach for outpatient assessment of the turnover of apolipoprotein B (ApoB) 100 in NASH, from a single blood draw during 2H2O intake. Very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL) were isolated from plasma for analysis because these are the primary particles that transport triglycerides and cholesterol, respectively, in circulation. The main structural protein, apoB100, was analyzed for label incorporation by mass spectrometry because there is one ApoB100 molecule per particle and its dynamics represent the behavior of the intact particle. We took advantage of an existing clinical study that was designed for assessing de novo lipogenesis in NASH patients. Subjects had been labeled for three days with heavy water prior to a fasting blood draw. Lipoproteins were separated from plasma using ultracentrifugation and native-PAGE. Average plasma triglycerides, apoB, LDL-apoB levels were 208.1 +/- 17.4, 131.8 +/- 8.4, and 78 +/- 6.2 (mg/dl, average +/- SE), respectively. In NASH patients, VLDL-apoB displayed a fractional synthesis value near or at 100%, indicating that this pool was completely replaced after three days. In contrast, LDL-apoB fractional replacement rate (n=50 subjects) was 0.32 +/- 0.03 pools/day and the absolute synthesis rate was 25.1 +/- 2.3 mg/dl/day. In healthy subjects (n=8), the average fractional replacement rate and plasma triglycerides were 0.37 +/- 0.02 pools/day and 93.9 +/- 22.3 mg/dl, respectively. In conclusion, our results show that LDL- apoB kinetics can be measured by use of 2 H 2 O labeling and tandem mass spectrometric analyses in NASH patients. This approach allows exploration of metabolic mechanisms underlying dyslipidemia in this increasingly important condition.
This paper classifies all memristors into three classes called Ideal, Generic, or Extended memristors. A subclass of Generic memristors is related to Ideal memristors via a one-to-one mathematical transformation, and is hence called Ideal Generic memristors. The concept of non-volatile memories is defined and clarified with illustrations. Several fundamental new concepts, including Continuum-memory memristor, POP (acronym for Power-Off Plot), DC V-I Plot, and Quasi DC V-I Plot, are rigorously defined and clarified with colorful illustrations. Among many colorful pictures the shoelace DC V-I Plot stands out as both stunning and illustrative. Even more impressive is that this bizarre shoelace plot has an exact analytical representation via 2 explicit functions of the state variable, derived by a novel parametric approach invented by the author.
In this paper we demonstrate that a recently introduced shape descriptor, the "shape context", can be used to quickly prune a search for similar shapes. Our representation for a shape is a discrete set of n points sampled from its internal and external contours. For each of these points, the shape context is a histogram of the relative positions of the n - 1 remaining points. We present two methods for rapid shape retrieval: one that does comparisons based on a small number of shape contexts and another that uses vector quantization in the space of shape contexts. We verify the discriminative power of these methods with tests on the Columbia (COIL-100) 3D object database and the Snodgrass and Vanderwart line drawings. The shape context-based methods are shown to quickly produce an accurate shortlist of candidates suitable for a more exact matching engine in spite of pose variation and occlusion.
Abstract A variety of resist systems have been studied that owe their sensitivity to the occurrence of catalyzed electrophilic rearrangements or substitution processes. In most designs, polyfunctional or polymer‐bound benzylic ethers, esters, or alcohols are used in the key step of the reaction, which is initiated by protonation of the latent electrophilic moiety, resulting in formation of a carbocationic center. Thermal activation of the electrophilic process leads to the formation of new C–C bonds with liberation of a proton; therefore the overall process is catalytic and amounts to chemical amplification. A variety of polymers and active small molecules that provide access to both negative and positive tone images have been tested, and sensitivities as high as 0.1 mJ/cm 2 have been measured. In addition, several image reversal schemes involving either selective silylation of non‐exposed areas or the in situ photogeneration of base have been tested and are presented.
Abstract The steady‐forced and earthquake responses of SDF systems with a non‐linear fluid viscous damper (FVD) are investigated. The energy dissipation capacity of the FVD is characterized by the supplemental damping ratio ζsd and its non‐linearity by a parameter designated α. It is found that the structural response is most effectively investigated in terms of ζ sd and α because (1) these two parameters are dimensionless and independent, and (2) the structural response varies linearly with the excitation intensity. Damper non‐linearity has essentially no influence on the peak response of systems in the velocity‐sensitive spectral region, but differences up to 14% were observed in the other spectral regions. The structural deformation is reduced by up to 25% when ζ sd = 5%; and by up to 60% when ζ sd = 30%. Non‐linear FVDs are advantageous because they achieve essentially the same reduction in system responses but with a significantly reduced damper force. For practical applications, a procedure is presented to estimate the design values of structural deformation and forces for a system with non‐linear FVD directly from the design spectrum. It is demonstrated that the earthquake‐induced force in a non‐linear FVD can be estimated from the damper force in a corresponding system with linear FVD, its peak deformation, and peak relative velocity; however, the relative velocity should not be approximated by the pseudo‐velocity as this approximation introduces a large error in the damper force. Finally, a procedure is presented to determine the non‐linear damper properties necessary to limit the structural deformation to some design value or the structural capacity for a given design spectrum. Copyright © 2002 John Wiley & Sons, Ltd.
This article examines several strategies that hospitals use to control their medical staffs. Such strategies include placing physicians on salary, developing exclusive hospital affiliations with physicians, and involving physicians in decision-making bodies. Using regression techniques, we investigate which hospitals are more likely to utilize these strategies and whether such strategies are effective in promoting physician-hospital integration. Contrary to our expectations, corporate hospital structures (e.g., for-profit hospitals, membership in multihospital systems) generally do not employ these strategies more often and oftentimes employ them less. There is also little evidence that control strategies are effective levers for increasing physician satisfaction or decreasing physician-hospital conflict. We suggest that control strategies are useful for purposes other than promoting physician-hospital integration. Finally, hospital ownership appears to exert the biggest effect on physician satisfaction and conflict.
