Protective heterologous antiviral immunity and enhanced immunopathogenesis mediated by memory T cell populations

A basic principle of immunology is that prior immunity results in complete protection against a homologous agent. In this study, we show that memory T cells specific to unrelated viruses may alter the host's primary immune response to a second virus. Studies with a panel of heterologous viruses, including lymphocytic choriomeningitis (LCMV), Pichinde (PV), vaccinia (VV), and murine cytomegalo (MCMV) viruses showed that prior immunity with one of these viruses in many cases enhanced clearance of a second unrelated virus early in infection. Such protective immunity was common, but it depended on the virus sequence and was not necessarily reciprocal. Cell transfer studies showed that both CD4 and CD8 T cell populations from LCMV-immune mice were required to transfer protective immunity to naive hosts challenged with PV or VV. In the case of LCMV-immune versus naive mice challenged with VV, there was an enhanced early recruitment of memory phenotype interferon (IFN) gamma-secreting CD4(+) and CD8(+) cells into the peritoneal cavity and increased IFN-gamma levels in this initial site of virus replication. Studies with IFN-gamma receptor knockout mice confirmed a role for IFN-gamma in mediating the protective effect by LCMV-immune T cell populations when mice were challenged with VV but not PV. In some virus sequences memory cell populations, although clearing the challenge virus more rapidly, elicited enhanced IFN-gamma-dependent immunopathogenesis in the form of acute fatty necrosis. These results indicate that how a host responds to an infectious agent is a function of its history of previous infections and their influence on the memory T cell pool.     

A Study for the Protection of Groundwater Production Zones from Polluting Sources Using GIS-Integrated Vulnerability Technique

Journal of Mining Science - The main objectives of this study are to determine the highly productive aquifer zones using the GIS-integrated vulnerability technique and to assess the protection of...     

Citizen engagement and urban change: Three case studies of material deliberation

Public participation in urban planning and development is a widely used process which seeks to enable better decision making. In this paper we address critiques of such deliberation – that it relies on the discursive to the detriment of experiential, material or affective modes of expression – and describe three case studies of participation which emphasise, in different ways, ‘material deliberation’. We close by discussing the ways in which such material deliberative practices can best be understood as components of a wider deliberative society.     

Long-range atmospheric transport of polycyclic aromatic hydrocarbons: a global 3-d model analysis including evaluation of arctic sources

We use the global 3-D chemical transport model GEOS-Chem to simulate long-range atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). To evaluate the model's ability to simulate PAHs with different volatilities, we conduct analyses for phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BaP). GEOS-Chem captures observed seasonal trends with no statistically significant difference between simulated and measured mean annual concentrations. GEOS-Chem also captures variability in observed concentrations at nonurban sites (r = 0.64, 0.72, and 0.74, for PHE, PYR, and BaP). Sensitivity simulations suggest snow/ice scavenging is important for gas-phase PAHs, and on-particle oxidation and temperature-dependency of gas-particle partitioning have greater effects on transport than irreversible partitioning or increased particle concentrations. GEOS-Chem estimates mean atmospheric lifetimes of <1 day for all three PAHs. Though corresponding half-lives are lower than the 2-day screening criterion for international policy action, we simulate concentrations at the high-Arctic station of Spitsbergen within four times observed concentrations with strong correlation (r = 0.70, 0.68, and 0.70 for PHE, PYR, and BaP). European and Russian emissions combined account for ～80% of episodic high-concentration events at Spitsbergen.     

A method for determining the absolute total electron content in the ionosphere on the basis of the analysis of the characteristics of unmodulated coherent multifrequency signals

A theoretical method for determining the absolute total electron content (TEC) on the basis of processing the phase of unmodulated coherent multifrequency signals is considered. Calculation of the values of the phase ambiguity and resolution in terms of TEC values is presented. A combination of the frequencies of coherent signals that enables reconstruction of the absolute TEC of the Earth’s ionosphere with the use of simple receiving facilities is substantiated.     

Starch characteristics of dry peas (Pisum sativum L.) grown in the USA

Starch samples from seven major dry pea (Pisum sativum L.) cultivars grown in North Dakota, US was isolated and their physicochemical properties investigated. The objective of the study was to establish the basic foundation of advanced research on physical and chemical modification to improve the functionality of dry pea starches grown in the region. Isolated starch samples were analysed by high performance size exclusion chromatography (HPSEC). Amylose percentages were in the range of 32.2–41.1%. Granules were elliptical or spherical with smooth surfaces based on microscopic analysis. Starch samples had similar gelatinisation transition temperatures and displayed ‘C patterns’. The swelling factors of dry pea starches influenced by temperature were determined at 10° intervals between 50 and 90 °C with continuous mixing. The pasting profiles were studied using a rapid visco analyzer (RVA), which exhibited different pasting profiles. This study indicated that dry pea cultivars grown in the region possess starch with different physicochemical characteristics.     

An investigation of the effect of high-energy milling time of Ti6Al4V biomaterial on the wear performance in the simulated body fluid environment

In this study, the effect of milling time on wear behaviour of the Ti6Al4V alloy produced with the high-energy milling method was investigated. The Ti6Al4V alloy was milled at five different milling times in a mechanical alloying device. The milled powders were cold-pressed under 620?MPa pressure, sintered at 1300°C for 2?h and cooled to room temperature in the furnace. The sintered alloys were characterised with SEM, XRD and hardness and density measurements. Wear tests were performed using a pin-on-disc type wear testing device, under three different loads, at four different sliding distances in simulated body fluid environment. Results showed a decreasing powder size with increasing milling time. The highest decline in size occurred for the powders milled for 120?min. The result of hardness measurements and wear tests showed that samples milled for 120?min had both the highest hardness value and the lowest weight loss.