Integration of electro-optical mechanical systems and medicine: Where are we and where can we go?

Microfabricated chip technologies offer researchers novel types of analysis of human clinical samples. Current examples of such technology include DNA amplification and analysis,and fluorescent cell analysis by flow cytometry. Potential applications include the development of rapid techniques for examining large numbers of cells in tissue or blood. This paper will outline criteria that successful devices must satisfy

Sampling bias in systems with structural heterogeneity and limited internal diffusion

Complex systems research is becomingly increasingly data-driven, particularly in the social and biological domains. Many of the systems from which sample data are collected feature structural heterogeneity at the mesoscopic scale (i.e. communities) and limited inter-community diffusion. Here we show that the interplay between these two features can yield a significant bias in the global characteristics inferred from the data. We present a general framework to quantify this bias, and derive an explicit corrective factor for a wide class of systems. Applying our analysis to a recent high-profile survey of conflict mortality in Iraq suggests a significant overestimate of deaths

Responses to Nitrogen Fertilizer in Dairy Pastures with Differing Phosphorus Fertility in South Eastern Australia

The application of nitrogen (N) fertilizer to temperate pastures is an increasingly popular management tool for boosting pasture production on dairy farms in Australia. However, limited information is available about N fertilizer responses that can be obtained from pastures with varying levels of phosphorus (P) fertility. A field experiment examining the initial and residual response of pasture growth to urea was carried out within a large dairy farmlet study, in October 1998. The four P fertility treatments (Olsen P values) ranged from 9 to 32 mg/kg. Dry matter yields increased with increasing N rates in all treatments, at both harvests. Only pastures with Olsen P values of \u3c 12 mg/kg had a significantly lower response to N fertilizer

Grazing Management Impacts on the Riparian Zone and Water Quality

Inappropriate farm management activities such as stock access to creeks, and poor fertiliser and effluent management can negatively impact riparian zones and waterways, contributing to increased in-stream nutrient, sediment and microbiological loads and loss of riparian biodiversity, amongst other impacts. Nutrient budgets for dairy systems indicate that on-farm nutrient accumulation and redistribution is common (Gourley 2004), which in large part is due to the uneven distribution of dairy cow dung and the nutrients they contain (Aarons et al., 2004). The \u27Gippsland Dairy Riparian Project Environmental Monitoring module\u27 was established in Jan. 2003 to monitor the impact of dairy farm management and changed riparian zone management on the riparian zone and water quality

Different mirror, A

Includes bibliographical references.Mirrors grown in the crystalline structure ease manufacture of vertical-cavity lasers, which emit collimated circular beams and can form large two-dimensional arrays. The authors discuss the fabrication of the surface emitting laser mirrors. By means of techniques such as molecular beam epitaxy and metal-organic vapor phase epitaxy, hundreds of layers of semiconductor materials can be grown one on top of the other. By mixing and matching the materials to create "designer" alloys, it is possible to grow a crystalline structure with all the electrical and optical properties desired for its various parts. This method of tailoring semiconductor structures is called bandgap engineering. The principles of the mirrors and their applications are discussed.This work was sponsored by the U.S. Department of Energy under contract number DE-AC04-94AL85000

Phosphorus Fertilizer and Stocking Rate Effects on Soil Microbial Biomass of a Long-Term Dairy Farmlet Experiment

The effects of a range of P fertilizer rates and dairy cow stocking rates on microbial biomass carbon and phosphorus were compared in a long-term farmlet trial in southeastern Australia. Pastures were stocked at 2, 3, or 4 cows/ha and received fertilizer at rates of 0, 35, 70 or 140 kgP/ha. There was no effect of either P fertilizer rate or stocking rate on microbial biomass C from 1995 to 1998. Increasing P application rate significantly increased the chloroform-released microbial P flush measured, but stocking rate had no effect on microbial P. There were significant temporal changes, with the seasonal effects of soil temperature and moisture overriding treatment effects on these microbial measurements

Fertiliser Responses and Soil Test Calibrations for Grazed Pastures in Australia

On-farm management of fertiliser is of major economic significance to the Australian grazing industries, based on expenditure on fertiliser and higher farm productivity that fertiliser use supports. However the application of fertiliser has traditionally been an inexact and inefficient process (Peverill et al. 1999) and there is increasing pressure for nutrient losses from agriculture to be minimised. The improved adoption and application of tools like soil testing can make substantial improvements in nutrient use efficiency but interpretation needs to be based on the best available information. This paper reports on the collation of current and historical experimental data relating to pasture production - fertiliser response relationships (nitrogen, phosphorus, potassium and sulphur) for various pasture types, climatic zones and soils across Australia

SALIVARY ANTIMICROBIAL PROTEIN RESPONSE TO PROLONGED RUNNING

Prolonged exercise may compromise immunity through a reduction of salivary antimicrobial proteins (AMPs). Salivary IgA (IgA) has been extensively studied, but little is known about the effect of acute, prolonged exercise on AMPs including lysozyme (Lys) and lactoferrin (Lac). Objective: To determine the effect of a 50-km trail race on salivary cortisol (Cort), IgA, Lys, and Lac. Methods: 14 subjects: (6 females, 8 males) completed a 50km ultramarathon. Saliva was collected pre, immediately after (post) and 1.5 hrs post race ( 1.5). Results: Lac concentration was higher at 1.5 hrs post race compared to post exercise (p<0.05). Lys was unaffected by the race (p>0.05). IgA concentration, secretion rate, and IgA/Osm were lower 1.5 hrs post compared to pre race (p<0.05). Cort concentration was higher at post compared to 1.5 (p<0.05), but was unaltered from pre race levels. Subjects finished in 7.81 ± 1.2 hrs. Saliva flow rate did not differ between time points. Saliva Osm increased at post (p<0.05) compared to pre race. Conclusions: The intensity could have been too low to alter Lys and Lac secretion rates and thus, may not be as sensitive as IgA to changes in response to prolonged running. Results expand our understanding of the mucosal immune system and may have implications for predicting illness after prolonged running