Overscreening Diamagnetism in Cylindrical Superconductor-Normal Metal-Heterostructures

We study the linear diamagnetic response of a superconducting cylinder coated by a normal-metal layer due to the proximity effect using the clean limit quasiclassical Eilenberger equations. We compare the results for the susceptibility with those for a planar geometry. Interestingly, for $R\sim d$ the cylinder exhibits a stronger overscreening of the magnetic field, i.e., at the interface to the superconductor it can be less than (-1/2) of the applied field. Even for $R\gg d$, the diamagnetism can be increased as compared to the planar case, viz. the magnetic susceptibility $4\pi\chi$ becomes smaller than -3/4. This behaviour can be explained by an intriguing spatial oscillation of the magnetic field in the normal layer

Effects of Combination Antiretroviral Therapies on the Risk of Myocardial Infarction Among HIV Patients

Cohort studies have demonstrated greater risk of myocardial infarction (MI) associated with specific antiretroviral use, while meta-analyses of randomized controlled trials have not. These differences may be due to inherent biases in the observational study design or to the limited duration of randomized trials. We conducted a new-user, active-comparator cohort study emulating a randomized controlled trial comparing initiation of several antiretrovirals as part of combination antiretroviral therapy (cART) and MI

Validation of Medicaid Claims-based Diagnosis of Myocardial Infarction Using an HIV Clinical Cohort

In non-experimental comparative effectiveness research using healthcare databases, outcome measurements must be validated to evaluate and potentially adjust for misclassification bias. We aimed to validate claims-based myocardial infarction algorithms in a Medicaid population using an HIV clinical cohort as the gold standard

An efficient method for computing steady state solutions with Gillespie’s direct method

Gillespie’s direct method is a stochastic simulation algorithm that may be used to calculate the steady state solution of a chemically reacting system. Recently the all possible states method was introduced as a way of accelerating the convergence of the simulations. We demonstrate that while the all possible states (APS) method does reduce the number of required trajectories, it is actually much slower than the original algorithm for most problems. We introduce the elapsed time method, which reformulates the process of recording the species populations. The resulting algorithm yields the same results as the original method, but is more efficient, particularly for large models. In implementing the elapsed time method, we present robust methods for recording statistics and empirical probability distributions. We demonstrate how to use the histogram distance to estimate the error in steady state solutions

Optimization of reactor configuration in coal liquefaction

This quarterly report covers activities of Optimization of Reactor Configuration in Coal Liquefaction during the period October 1 - December 31, 1992, at Hydrocarbon Research, Inc. in Lawrenceville and Princeton, New Jersey. This DOE contract period is from October 1, 1991 to September 30, 1993. The overall objective of the program is to achieve a new approach to liquefaction that generates an all distillates product slate at reduced cost of about $25 per barrel of crude oil equivalent. The quarterly report covers work on Laboratory Support, Laboratory Scale Operations, Technical Assessment, and Project Management. Work undertaken in this fifth quarter concerned with completing the analyses of recovered catalysts from the previous fixed bed tests and the planning of microautoclave tests to evaluate the three-stage and interstage stream reconcentration concepts

Catalytic multi-stage liquefaction of coal

This quarterly report covers activities of Catalytic Multi-Stage Liquefaction of Coal dozing the period December 8--December 31, 1992, at Hydrocarbon Research, Inc. in Lawrenceville and Princeton, New Jersey. This DOE contract period is from December 8, 1992 to December 7, 1994. The overall objective of the program is to produce liquid fuels from direct coal liquefaction at a cost that is competitive with conventional fuels. Specifically, this continuous bench-scale program examine new ideas in areas such as: low temperature pretreatments, more effective catalysts, on-line hydrotreating, new coal feedstocks, other hydrogen sources, more concentrated coal feeds and other highly responsive process improvements while assessing the design and economics of bench-scale results. The quarterly report covers work on Project Management Plan, Laboratory Scale Studies, Continuous Bench-Scale Operations, Technical Assessment and Project Management/Administration

Optimization of reactor configuration in coal liquefaction

This quarterly report covers activities of optimization of Reactor Configuration in Coal Liquefaction during the period July 1--September 30, 1992, at Hydrocarbon Research, Inc. in Lawrenceville and Princeton, New Jersey. This DOE contract period is from October 1, 1991 to September 30, 1993. The overall objective of the program is to achieve a new approach to liquefaction that generates an all distillates product slate at reduced cost of about $25 per barrel of crude oil equivalent. The quarterly report covers work on Laboratory Support, Laboratory Scale Operations, Technical Assessment, and Project Management

Catalytic multi-stage liquefaction of coal twelth quarterly report for the period 1 July 1995--30 September 1995

The overall objective of this program is to produce liquid fuels from coal by direct liquefaction at a cost that is competitive with conventional fuels. Specifically, this continuous bench-scale program contains provisions to examine new ideas in areas such as: low temperature pretreatments, more effective catalysts, on-line hydrotreating, new coal feedstocks, other hydrogen sources, more concentrated coal feeds and other highly responsive process improvements while assessing the design and economics of the bench- scale results. This quarterly report covers work on Laboratory Scale Studies, Continuous Bench-Scale Operations, Technical Assessment and Project Management

Two-stage, closed coupled catalytic liquefaction of coal. Sixteenth quarterly report, 1 July 1992--30 September 1992

This quarterly report covers activities of the Two-Stage, Close-Coupled Catalytic Liquefaction of Coal Program during the period of July 1--September 30, 1992, at Hydrocarbon Research, Inc., in Lawrenceville and Princeton, New Jersey. This DOE contract period is from October 1, 1998 to December 31, 1992. The overall purpose of the program is to achieve higher yields of better quality transportation and turbine fuels and to lower the capital and production costs in order to make the products from direct coal liquefaction competitive with other fossil fuel products. The quarterly report covers work on Laboratory testing, Bench Scale Studies and PDU Activities focusing on scale-up of the Catalytic Two-Stage Liquefaction (CTSL) processing of sub-bituminous Black Thunder Coal