Issues pertaining to laboratory evaluation of hot mix asphalt

Since the early 1900\u27s, research in the Hot Mix Asphalt (HMA) industry has focused on the development of a more mechanistic design approach and improving quality control procedures. This paper presents the results of three observational studies conducted to evaluate problems associated with relatively recent developments in HMA design and analysis as follows 1) Aggregate degradation due to laboratory compaction using the Superpave™ Gyratory Compactor (SGC). 2) Aggregate degradation due to ignition oven testing using the NCAT Asphalt Content Tester. 3) Comparison of the bulk specific gravity, saturated, surface dry (SSD) method with bulk specific gravity, Parafilm™ method for HMA specimens. These observational studies included HMA samples from over 20 paving projects constructed in the state of Tennessee during the 1998 construction season. The results of these studies suggest that there is no significant degradation of aggregate resulting from the SGC or the NCAT ignition oven for HMA typically produced in Tennessee. The results suggest that the use of the Parafilm™ method in measuring bulk specific gravity of compacted HMA specimens results in an air-void content approximately 2% higher than using SSD methods. It is not clear which method produces a more correct measure of air-void content. The results also suggest that the SSD method is more suitable for typical HMA specimens containing less than 6% air-voids. It is suspected the internal voids are not interconnected with surface voids at this level of compaction

Assessment and Revision of Clinical Pharmacy Practice Internet Websites

Background: Health care professionals, trainees, and patients use the Internet extensively. Editable Web sites may contain inaccurate, incomplete, and/or outdated information that may mislead the public’s perception of the topic. Objective: To evaluate the editable, online descriptions of clinical pharmacy and pharmacist and attempt to improve their accuracy. Methods: The authors identified key areas within clinical pharmacy to evaluate for accuracy and appropriateness on the Internet. Current descriptions that were reviewed on public domain Web sites included: (1) clinical pharmacy and the clinical pharmacist, (2) pharmacy education, (3) clinical pharmacy and development and provision for reimbursement, (4) clinical pharmacists and advanced specialty certifications/training opportunities, (5) pharmacists and advocacy, and (6) clinical pharmacists and interdisciplinary/interprofessional content. The authors assessed each content area to determine accuracy and prioritized the need for updating, when applicable, to achieve consistency in descriptions and relevancy. The authors found that Wikipedia, a public domain that allows users to update, was consistently the most common Web site produced in search results. Results: The authors’ evaluation resulted in the creation or revision of 14 Wikipedia Web pages. However, rejection of 3 proposed newly created Web pages affected the authors’ ability to address identified content areas with deficiencies and/or inaccuracies. Conclusions: Through assessing and updating editable Web sites, the authors strengthened the online representation of clinical pharmacy in a clear, cohesive, and accurate manner. However, ongoing assessments of the Internet are continually needed to ensure accuracy and appropriateness

Different paths to the modern state in Europe: the interaction between domestic political economy and interstate competition

Theoretical work on state formation and capacity has focused mostly on early modern Europe and on the experience of western European states during this period. While a number of European states monopolized domestic tax collection and achieved gains in state capacity during the early modern era, for others revenues stagnated or even declined, and these variations motivated alternative hypotheses for determinants of fiscal and state capacity. In this study we test the basic hypotheses in the existing literature making use of the large date set we have compiled for all of the leading states across the continent. We find strong empirical support for two prevailing threads in the literature, arguing respectively that interstate wars and changes in economic structure towards an urbanized economy had positive fiscal impact. Regarding the main point of contention in the theoretical literature, whether it was representative or authoritarian political regimes that facilitated the gains in fiscal capacity, we do not find conclusive evidence that one performed better than the other. Instead, the empirical evidence we have gathered lends supports to the hypothesis that when under pressure of war, the fiscal performance of representative regimes was better in the more urbanized-commercial economies and the fiscal performance of authoritarian regimes was better in rural-agrarian economie

Use of a mixed tissue RNA design for performance assessments on multiple microarray formats

The comparability and reliability of data generated using microarray technology would be enhanced by use of a common set of standards that allow accuracy, reproducibility and dynamic range assessments on multiple formats. We designed and tested a complex biological reagent for performance measurements on three commercial oligonucleotide array formats that differ in probe design and signal measurement methodology. The reagent is a set of two mixtures with different proportions of RNA for each of four rat tissues (brain, liver, kidney and testes). The design provides four known ratio measurements of >200 reference probes, which were chosen for their tissue-selectivity, dynamic range coverage and alignment to the same exemplar transcript sequence across all three platforms. The data generated from testing three biological replicates of the reagent at eight laboratories on three array formats provides a benchmark set for both laboratory and data processing performance assessments. Close agreement with target ratios adjusted for sample complexity was achieved on all platforms and low variance was observed among platforms, replicates and sites. The mixed tissue design produces a reagent with known gene expression changes within a complex sample and can serve as a paradigm for performance standards for microarrays that target other species

Renal replacement therapy in acute kidney injury: controversy and consensus

Renal replacement therapies (RRTs) represent a cornerstone in the management of severe acute kidney injury. This area of intensive care and nephrology has undergone significant improvement and evolution in recent years. Continuous RRTs have been a major focus of new technological and treatment strategies. RRT is being used increasingly in the intensive care unit, not only for renal indications but also for other organ-supportive strategies. Several aspects related to RRT are now well established, but others remain controversial. In this review, we review the available RRT modalities, covering technical and clinical aspects. We discuss several controversial issues, provide some practical recommendations, and where possible suggest a research agenda for the future

Nanotechnology and the Treatment of HIV Infection

Suboptimal adherence, toxicity, drug resistance and viral reservoirs make the lifelong treatment of HIV infection challenging. The emerging field of nanotechnology may play an important role in addressing these challenges by creating drugs that possess pharmacological advantages arising out of unique phenomena that occur at the “nano” scale. At these dimensions, particles have physicochemical properties that are distinct from those of bulk materials or single molecules or atoms. In this review, basic concepts and terms in nanotechnology are defined, and examples are provided of how nanopharmaceuticals such as nanocrystals, nanocapsules, nanoparticles, solid lipid nanoparticles, nanocarriers, micelles, liposomes and dendrimers have been investigated as potential anti-HIV therapies. Such drugs may, for example, be used to optimize the pharmacological characteristics of known antiretrovirals, deliver anti-HIV nucleic acids into infected cells or achieve targeted delivery of antivirals to the immune system, brain or latent reservoirs. Also, nanopharmaceuticals themselves may possess anti-HIV activity. However several hurdles remain, including toxicity, unwanted biological interactions and the difficulty and cost of large-scale synthesis of nanopharmaceuticals