The National Center for Asphalt Technology (NCAT) completed a roundrobin study in March to determine the accuracy and precision of the NCAT asphalt content tester. The Center has conducted research since 1990 to develop this test method for determining asphalt content of hot mix asphalt (HMA) mixtures by ignition (See the fall, 1994, issue of Asphalt Technology News). In the ignition method, a ...

The frequency that multiple different subtypes of hepatitis C virus (HCV) simultaneously infect a given individual is controversial. To address this question, heteroduplex mobility analysis (HMA) of portions of the HCV core and envelope 1 region was optimized for sensitive and specific detection of mixtures of HCV genomes of different genotype or subtype. Using the standard HCV genotyping appro...

Heteroduplex mobility analysis (HMA) was used to genotype hepatitis C viruses (HCV) with PCR fragments derived from the 5' untranslated region (5'-UTR) or the NS5b region. HCV 5'-UTR fragments were amplified from 296 serum samples by use of a combined reverse transcription-PCR assay, and the genotypes of isolates were determined by sequencing. HCV genotype distributions in Australia were 39% fo...

Porcine reproductive and respiratory syndrome has been devastating the swine industry since the late 1980s. The disease has been controlled, to some extent, through the use of modified live-attenuated (MLV) vaccines once available. However, such a practice periodically resulted in isolation or detection of vaccine-like viruses from pigs as determined by a partial genomic sequencing. In this stu...

The anisotropy refers to the material properties that are direction dependant. In the past, the HMA has been typically modeled as an isotropic material due to a lack of sufficient data for detailed quantification of its direction-dependency. However, it is reasonable to assert that HMA may exhibit significant anisotropic behaviour due to the major compaction direction and the resulting preferre...

Hot-mix asphalt (HMA) plays a vital role in the U.S. transportation system, and will continue to do so into the new millennium. Thus it is important to examine both the state of the art of and future prospects for HMA in a number of key areas, including the role of the user agency or owner, materials, processing, transportation, lay-down procedures, testing for quality and performance, work zon...

Grid systems can provide a virtual framework for management and scheduling of resources across different domains. This paper proposes an HMA-base grid resource scheduling system to implement resource finding and scheduling. A new cost model is also given, considering resource finding cost and resource deciding cost beyond traditional model. In succession, the new cost model is integrated into t...

The increasing prevalence of influenza viruses with resistance to approved antivirals highlights the need for new anti-influenza therapeutics. Here we describe the functional properties of hexamethylene amiloride (HMA)-derived compounds that inhibit the wild-type and adamantane-resistant forms of the influenza A M2 ion channel. For example, 6-(azepan-1-yl)-N-carbamimidoylnicotinamide ( 9: ) inh...