Raised cortisol excretion rate in urine and contamination by topical steroids

No abstract available

Super p-branes

It is shown that the extension of the spacetime supersymmetric Green- Schwarz covariant superstring action to p-dimensional extended objects (p-branes) is possible if and only if the on-shell p-dimensional bose and fermi degrees of freedom are equal. This is further evidence for world-tube supersymmetry in these models. All the p-brane models are related to superstring actions in d = 3, 4, 6 or 10 dimensions by double dimensional reduction, (which we generalise to reduction on arbitrary compact spaces), and we also show how they may be considered as topological defects of supergravity theories

Self-consistent Treatment of Crystal-Electric-Field-Levels in the Anderson Lattice

We consider an Anderson lattice model with a spin 1/2 degenerated conduction electron band and localized ionic CEF-levels, classified according to the irreducible representation of the point group of the lattice. We present the self-consistency equations for local approximations ("$d\rightarrow\infty"$ approximation) for the periodic Anderson model. It leads to a matrix formulation of the effective local density of states and the lattice $f$-Green's function. We derive the quasi-particle life-time which enters the Boltzmann transport equations. The impact of a $k$-dependent hybridization is discussed. We prove that vertex corrections will vanish, as long as all states of an irreducible representation couple to the conduction electron band with a hybridization matrix element of the same parity.Comment: 3 pages, REVTeX type, proceedings of SCES96 Z\"uric

Carbon sequestration and biogeochemical cycling in a saltmarsh subject to coastal managed realignment

Globally, wetlands provide the largest terrestrial carbon (C) store, and restoration of degraded wetlands provides a potentially important mechanism for climate change mitigation. We examined the potential for restored saltmarshes to sequester carbon, and found that they can provide a modest, but sustained, sink for atmospheric CO2. Rates of C and nutrient cycling were measured and compared between a natural saltmarsh (high- and low-shore locations), claimed arable land on former high-shore saltmarsh and a managed realignment restoration site (high- and low-shore) in transition from agricultural land to saltmarsh 15 years after realignment, at Tollesbury, Essex, UK. We measured pools and turnover of C and nitrogen (N) in soil and vegetation at each site using a range of methods, including gas flux measurement and isotopic labelling. The natural high-shore site had the highest soil organic matter concentrations, topsoil C stock and below-ground biomass, whereas the agricultural site had the highest total extractable N concentration and lowest soil C/N ratio. Ecosystem respiration rates were similar across all three high-shore sites, but much higher in both low-shore sites, which receive regular inputs of organic matter and nutrients from the estuary. Total evolution of 14C-isotopically labelled substrate as CO2 was highest at the agricultural site, suggesting that low observed respiration rates here were due to low substrate supply (following a recent harvest) rather than to inherently low microbial activity. The results suggest that, after 15 years, the managed realignment site is not fully equivalent to the natural saltmarsh in terms of biological and chemical function. While above ground biomass, extractable N and substrate mineralisation rates in the high-shore site were all quite similar to the natural site, less dynamic ecosystem properties including soil C stock, C/N ratio and below-ground biomass all remained more similar to the agricultural site. These results suggest that reversion to natural biogeochemical functioning will occur following restoration, but is likely to be slow; we estimate that it will take approximately 100 years for the restored site to accumulate the amount of C currently stored in the natural site, at a rate of 0.92 t C ha−1 yr−1

Towards a killer app for the Semantic Web

Killer apps are highly transformative technologies that create new markets and widespread patterns of behaviour. IT generally, and the Web in particular, has benefited from killer apps to create new networks of users and increase its value. The Semantic Web community on the other hand is still awaiting a killer app that proves the superiority of its technologies. There are certain features that distinguish killer apps from other ordinary applications. This paper examines those features in the context of the Semantic Web, in the hope that a better understanding of the characteristics of killer apps might encourage their consideration when developing Semantic Web applications

ARQ-197, a small-molecule inhibitor of c-Met, reduces tumour burden and prevents myeloma-induced bone disease in vivo

The receptor tyrosine kinase c-Met, its ligand HGF, and components of the downstream signalling pathway, have all been implicated in the pathogenesis of myeloma, both as modulators of plasma cell proliferation and as agents driving osteoclast differentiation and osteoblast inhibition thus, all these contribute substantially to the bone destruction typically caused by myeloma. Patients with elevated levels of HGF have a poor prognosis, therefore, targeting these entities in such patients may be of substantial benefit. We hypothesized that ARQ-197 (Tivantinib), a small molecule c-Met inhibitor, would reduce myeloma cell growth and prevent myeloma-associated bone disease in a murine model. In vitro we assessed the effects of ARQ-197 on myeloma cell proliferation, cytotoxicity and c-Met protein expression in human myeloma cell lines. In vivo we injected NOD/SCID-γ mice with PBS (non-tumour bearing) or JJN3 cells and treated them with either ARQ-197 or vehicle. In vitro exposure of JJN3, U266 or NCI-H929 cells to ARQ-197 resulted in a significant inhibition of cell proliferation and an induction of cell death by necrosis, probably caused by significantly reduced levels of phosphorylated c-Met. In vivo ARQ-197 treatment of JJN3 tumour-bearing mice resulted in a significant reduction in tumour burden, tumour cell proliferation, bone lesion number, trabecular bone loss and prevented significant decreases in the bone formation rate on the cortico-endosteal bone surface compared to the vehicle group. However, no significant differences on bone parameters were observed in non-tumour mice treated with ARQ-197 compared to vehicle, implying that in tumour-bearing mice the effects of ARQ-197 on bone cells was indirect. In summary, these res ults suggest that ARQ-197 could be a promising therapeutic in myeloma patients, leading to both a reduction in tumour burden and an inhibition of myeloma-induced bone disease

Irrigation Management

Competition for limited water supplies continues to restrict water available for irrigation. Irrigated agricultural must continually improve irrigation management to continue producing food, fiber and fuel for a growing world population. Precision irrigation is the process of applying the right amount of water at the right time and place to obtain the best use of available water. Precision irrigation management is needed on large irrigation projects so water delivery matches irrigation needs and on individual fields to apply the right amount of water at the right time and place. Technology is commercially available to precisely apply water when and where it is needed by crops, however, user-friendly decision tools are still needed to quantify specific irrigation needs and control water application within fields. Integrating information from various sensors and systems into a decision support program will be critical to highly managed, spatially varied irrigation

Evaluating the surface irrigation soil loss (SISL) model

Although the percentage of surface irrigated land in the United States is declining, it is still used on 43% of the irrigated land, and 51% of the surface irrigated land is irrigated down furrows or rows (USDA, 2004). Water flowing in irrigation furrows often detaches and transports soil, reducing crop productivity and impairing off-site water quality. Crop yields were at least 25% less on fields eroded from over 80 years of furrow irrigation in south-central Idaho (Carter et al., 1985). Measured soil loss from furrow irrigated fields in this area varied from 1 to 141 Mg ha-1 annually (Berg and Carter, 1980) while the annual average soil loss from the entire irrigated tract was 0.46 Mg ha-1 in 1971 (Brown et al, 1974). This soil, and associated nutrients, is transported with irrigation water as it returns to the Snake River. The Natural Resources Conservation Service (NRCS) and other land planning agencies need a tool to predict furrow irrigation erosion to assess the extent of the problem and to compare conservation practices applied to irrigated land. An evaluation of the Water Erosion Prediction Project (WEPP) model indicated that it could not be used to predict furrow irrigation erosion without substantially adjusting erodibility parameter values (Bjorneberg et al., 1999). The model also over-predicted sediment transport capacity resulting in no predicted sediment deposition on the lower end of fields, although data and observations document much on-field deposition (Bjorneberg et al., 1999). The Idaho NRCS, in consultation with scientists and engineers at the Northwest Irrigation and Soils Research Laboratory, Kimberly, Idaho, developed a simple empirical model for estimating annual irrigation-induced soil loss from furrow irrigated fields. The SISL (surface irrigation soil loss) model was developed in 1991 based on over 200 field-years of data from southern Idaho. This model estimates soil loss at the end of the furrow and does not account for deposition or additional erosion that may occur in the drainage ditch at the end of the field. The only published documentation of this model is Idaho NRCS Agronomy Technical Note No. 32. Idaho NRCS uses this model to assess benefits of conservation practices, such as converting from furrow to sprinkler irrigation, but this model has not been independently evaluated. Therefore, the objective of this study was to compare the SISL model with erosion data collected from furrow irrigated fields near Kimberly, Idaho and Prosser, Washington

Roadside vegetation management guidelines

Integrated Roadside Vegetation Management (IRVM) i s a collective process that uses the most appropriate scientifically-based vegetation management techniques to meet the department' s goals in both an environmentally and economically sound manner. IRVM recognizes that every component of a program can be greatly dependent upon the other components. Whether cultural, chemical or biological, all components are used to manipulate the roadside plant community during a short period of time but with longterm goals. If the guidelines in this manual are followed, they will help ensure that the department is accountable and that goals are met as efficiently and economically as possible.N

How the composition of sandstone matrices affects rates of soil formation

Soils deliver multiple ecosystem services and their long-term sustainability is fundamentally controlled by the rates at which they form and erode. Our knowledge and understanding of soil formation is not commensurate with that of soil erosion, in part due to the difficulty of measuring the former. However, developments in cosmogenic radionuclide accumulation models have enabled soil scientists to more accurately constrain the rates at which soils form from bedrock. To date, all three major rock types – igneous, sedimentary and metamorphic lithologies – have been examined in such work. Soil formation rates have been measured and compared between these rock types, but the impact of rock characteristics on soil formation rates, such as rock matrices and mineralogy, have seldom been explored. In this UK-based study, we used cosmogenic radionuclide analysis to investigate whether the lithological variability of sandstone governs pedogenesis. Soil formation rates were measured on two arable hillslopes at Woburn and Hilton, which are underlain by different types of arenite sandstone. Rates were faster at Woburn, and we suggest that this is due to the fact that the Woburn sandstone formation is less cemented that that at Hilton. Similarly, rates at Woburn and Hilton were found to be faster than those measured at two other sandstone-based sites in the UK, and faster than those compiled in a global inventory of cosmogenic studies on sandstone-based soils. We suggest that the cementing agents present in matrix-abundant wackes studied previously may afford these sandstones greater structural integrity and resistance to weathering. This work points to the importance of factoring bedrock matrices into our understanding of soil formation rates, and the biogeochemical cycles these underpi