Remote sensing of land use and water quality relationships - Wisconsin shore, Lake Michigan

This investigation assessed the utility of remote sensing techniques in the study of land use-water quality relationships in an east central Wisconsin test area. The following types of aerial imagery were evaluated: high altitude (60,000 ft) color, color infrared, multispectral black and white, and thermal; low altitude (less than 5000 ft) color infrared, multispectral black and white, thermal, and passive microwave. A non-imaging hand-held four-band radiometer was evaluated for utility in providing data on suspended sediment concentrations. Land use analysis includes the development of mapping and quantification methods to obtain baseline data for comparison to water quality variables. Suspended sediment loads in streams, determined from water samples, were related to land use differences and soil types in three major watersheds. A multiple correlation coefficient R of 0.85 was obtained for the relationship between the 0.6-0.7 micrometer incident and reflected radiation data from the hand-held radiometer and concurrent ground measurements of suspended solids in streams. Applications of the methods and baseline data developed in this investigation include: mapping and quantification of land use; input to watershed runoff models; estimation of effects of land use changes on stream sedimentation; and remote sensing of suspended sediment content of streams. High altitude color infrared imagery was found to be the most acceptable remote sensing technique for the mapping and measurement of land use types

Bifurcations and Hysteresis in the Dynamics of Small Populations of Spherical Magnets

If you heat up some kinds of metals and then cool them down next to a magnet, they will be a magnet when they cool, but if they cool down away from a magnet, they will just be a lump of metal. This is an example of hysteresis and it’s very important for lots of technology. Another example of hysteresis might be a water tower pump that turns on when the tower is nearly empty and keeps going until the tower is nearly full. Whether or not the pump is on when the tower is half full depends on what the condition of the tower was recently. Hysteresis more generally can be thought of as when somethings present condition depends very strongly on what it’s history was. A counter example would be for a gas, when you know it’s temperature and pressure and volume, that’s all that matters. Many systems with hysteresis are complicated, but this research has found that some very simple arrangements of the simplest magnets can have still have hysteresis. I show this primarily by looking at how the systems move around their resting position. This research was funded by an NSF grant

A sensetive zonagenetic assay for rapid in vivo assessment of estrogenic potency of xenobiotics and mycotoxins

Mounting evidence confirms that hepatic biosynthetic processes are essential for female sexual maturation in fish, which is directly controlled by estrogens. These oogenetic events (zonagenesis and vitellogenesis) are induced in both sexes by estrogens. In this paper, we report the induction of zona radiata (zr) proteins and vitellogenin in primary hepatocytes from Atlantic salmon (Salmo salar L.) exposed to xenoestrogens and mycotoxins. Cells were treated with doses of 1, 5, and 10 microM 4-nonylphenol (4-NP), o, p'-DDT, lindane ([gamma]-HCH), and bisphenol A (BPA), which all induced zr proteins and vitellogenin in an approximate dose-dependent manner. Hepatocytes were also treated with combinations of xenoestrogens at 1 or 2 microM, resulting in elevated levels of both zr proteins and vitellogenin, compared to single treatment. The estrogenic activity of the mycotoxin zearalenone (ZEA) and its metabolites [alpha]-ZEA) and ss-zearalenol (ss-ZEA)], with regard to zonagenesis and vitellogenesis, was assessed in this assay system. Mycotoxins were used at concentrations of 10, 100, or 1,000 nM. All induced zr proteins and vitellogenin, with [alpha]-ZEA being the strongest inducer. When cells were treated with xenoestrogens or mycotoxins in combination with an estrogen receptor inhibitor (ICI 182,780), the induction of both zr proteins and vitellogenin was inhibited in all cases. Thus, the reported estrogen effects are bonafide estrogen responses. Zona radiata proteins were more responsive than vitellogenin to both xenoestrogens and mycotoxins. The versatility and sensitivity of the hepatocyte assay demonstrates that biosynthesis of zr proteins provides a new supplementary method for estimating xenoestrogenicity and mycotoxin action.publishedVersio

Load-sharing with degradation management in a compressor station

Management of compressor degradation is often considered from the perspective of maintenance of the compressor, but most frameworks for the operation of compressors do not take degradation into account. This paper proposes a method for operation of compressors that takes into account the current level of degradation in order to manage further degradation. The algorithm can be used in maintenance planning frameworks, in particular if the timings of maintenance activities are fixed. The algorithm can extend the lifetime of a compressor by mitigating its degradation, or, conversely, can intensify the degradation to reach the maximum level in time for planned maintenance. The performance of the algorithm has been demonstrated in a case study for five compressors. A comparison with equal load approach shows that the new algorithm improves the operation of the system by managing the degradation of selected compressors. Explicit management of degradation allows an extension of the lifetime of selected compressors before maintenance must be performed. Conversely, by ensuring that the desired level of degradation is attained before pre-planned maintenance actions, it contributes to increased efficacy of maintenance actions. Note to Practitioners —The paper presents a new framework for load-sharing in a compressor station with compressors subject to degradation. The main innovation of the framework is the use of relationships between custom degradation indicators to manage degradation of the compressors. The results in the paper prove that it is possible to manage degradation in an industrial setting by adjusting the load of each compressor. From a practical perspective, the framework allows more degraded compressors to follow the less degraded compressors (called leaders). The simplicity of the proposed framework enables an intuitive choice of leaders, in particular in compressor stations with more than two compressors. Focused directly on the load sharing, the framework al..

Inhibition of nuclear factor-kappa B differentially affects thyroid cancer cell growth, apoptosis, and invasion

<p>Abstract</p> <p>Background</p> <p>Nuclear factor-κB (NF-κB) is constitutively activated in many cancers and plays a key role in promoting cell proliferation, survival, and invasion. Our understanding of NF-κB signaling in thyroid cancer, however, is limited. In this study, we have investigated the role of NF-κB signaling in thyroid cancer cell proliferation, invasion, and apoptosis using selective genetic inhibition of NF-κB in advanced thyroid cancer cell lines.</p> <p>Results</p> <p>Three pharmacologic inhibitors of NF-κB differentially inhibited growth in a panel of advanced thyroid cancer cell lines, suggesting that these NF-κB inhibitors may have off-target effects. We therefore used a selective genetic approach to inhibit NF-κB signaling by overexpression of a dominant-negative IκBα (mIκBα). These studies revealed decreased cell growth in only one of five thyroid cancer cell lines (8505C), which occurred through a block in the S-G2/M transition. Resistance to TNFα-induced apoptosis was observed in all cell lines, likely through an NF-κB-dependent mechanism. Inhibition of NF-κB by mIκBα sensitized a subset of cell lines to TNFα-induced apoptosis. Sensitive cell lines displayed sustained activation of the stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) pathway, defining a potential mechanism of response. Finally, NF-κB inhibition by mIκBα expression differentially reduced thyroid cancer cell invasion in these thyroid cancer cell lines. Sensitive cell lines demonstrated approximately a two-fold decrease in invasion, which was associated with differential expression of MMP-13. MMP-9 was reduced by mIκBα expression in all cell lines tested.</p> <p>Conclusions</p> <p>These data indicate that selective inhibition of NF-κB represents an attractive therapeutic target for the treatment of advanced thyroid. However, it is apparent that global regulation of thyroid cancer cell growth and invasion is not achieved by NF-κB signaling alone. Instead, our findings suggest that other important molecular processes play a critical role in defining the extent of NF-κB function within cancer cells.</p