Evaluation of the Land Surface Water Budget in NCEP/NCAR and NCEP/DOE Reanalyses using an Off-line Hydrologic Model

The ability of the National Centers for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis (NRA1) and the follow-up NCEP/Department of Energy (DOE) reanalysis (NRA2), to reproduce the hydrologic budgets over the Mississippi River basin is evaluated using a macroscale hydrology model. This diagnosis is aided by a relatively unconstrained global climate simulation using the NCEP global spectral model, and a more highly constrained regional climate simulation using the NCEP regional spectral model, both employing the same land surface parameterization (LSP) as the reanalyses. The hydrology model is the variable infiltration capacity (VIC) model, which is forced by gridded observed precipitation and temperature. It reproduces observed streamflow, and by closure is constrained to balance other terms in the surface water and energy budgets. The VIC-simulated surface fluxes therefore provide a benchmark for evaluating the predictions from the reanalyses and the climate models. The comparisons, conducted for the 10-year period 1988–1997, show the well-known overestimation of summer precipitation in the southeastern Mississippi River basin, a consistent overestimation of evapotranspiration, and an underprediction of snow in NRA1. These biases are generally lower in NRA2, though a large overprediction of snow water equivalent exists. NRA1 is subject to errors in the surface water budget due to nudging of modeled soil moisture to an assumed climatology. The nudging and precipitation bias alone do not explain the consistent overprediction of evapotranspiration throughout the basin. Another source of error is the gravitational drainage term in the NCEP LSP, which produces the majority of the model\u27s reported runoff. This may contribute to an overprediction of persistence of surface water anomalies in much of the basin. Residual evapotranspiration inferred from an atmospheric balance of NRA1, which is more directly related to observed atmospheric variables, matches the VIC prediction much more closely than the coupled models. However, the persistence of the residual evapotranspiration is much less than is predicted by the hydrological model or the climate models

Principles of microRNA regulation of a human cellular signaling network

MicroRNAs (miRNAs) are endogenous 22-nucleotide RNAs, which suppress gene expression by selectively binding to the 3-noncoding region of specific message RNAs through base-pairing. Given the diversity and abundance of miRNA targets, miRNAs appear to functionally interact with various components of many cellular networks. By analyzing the interactions between miRNAs and a human cellular signaling network, we found that miRNAs predominantly target positive regulatory motifs, highly connected scaffolds and most downstream network components such as signaling transcription factors, but less frequently target negative regulatory motifs, common components of basic cellular machines and most upstream network components such as ligands. In addition, when an adaptor has potential to recruit more downstream components, these components are more frequently targeted by miRNAs. This work uncovers the principles of miRNA regulation of signal transduction networks and implies a potential function of miRNAs for facilitating robust transitions of cellular response to extracellular signals and maintaining cellular homeostasis

Engineering a primary waste treatment plant

This thesis deals with the design and construction of a primary waste treatment plant. The scope of work covered here, includes waste sampling and characterization, process design data gathering, process and mechanical design, cost estimate, and a general discussion of the construction and start-up. In the development of this work, it is assumed that a decision has been made to build the waste treatment plant, using a known process. Therefore, economic evaluations designed to determine return on investment and selection of a process, will not be discussed. The impact the capital investment associated with the waste treatment facility has on the overall production costs of the basic product oriented facility, is discussed

How Much Time for the General Chemistry Laboratory?

The method of teaching science in which a certain amount of opportunity is given each student for work by himself in the laboratory (the so-called individual laboratory method) is of fairly recent development. Many of the early American professors of chemistry did not believe that the beginning student should be allowed to set foot in a laboratory. This was undoubtedly due to the fact that these instructors were educated under the German system of class-room demonstration. According to Lucasse (1) the credit for the development of the first chemistry laboratory for instruction goes to Lomonossoff (1748). Later the passage of the Morrill Land Grant Act of 1862 caused a great development of the laboratory method, in that during the period 1880-1900 there were a great number of university laboratories constructed

Distribution And Enrichment Of Heavy Metals In Soils From Waste Dump Sites Within Imoru And Environs, Southwest Nigeria

Soil samples from waste dump sites from Imoru and the towns around it were analyzed for their cadmium, chromium, copper, manganese, nickel, lead and zinc contents in order to determine the distribution and enrichment of these metals in the area. Results show the average metal content as Cd (1.18 mg/kg-1), Cr (0.69 mgkg-1), Cu (9.61 mgkg-1), Mn (93.41 mgkg-1), Ni (2.94 mgkg-1), Pb (12.24 mgkg-1) and Zn (78.82 mgkg-1).Using Enrichment Factor (EF) the soils were classified as deficient to moderately enriched with Cd and Cr while they are deficient to minimally enriched with Cu, Mn, Ni and Zn. Calculated Geo-accumulation index (Igeo) shows the soil to be unpolluted to moderately polluted of all trace metals analyzed for. The C / P index places the soil as very slightly contaminated to slightly contaminated by Cr, Pb and Ni; severely contaminated to moderately polluted by Cd; and very slightly to severely contaminated with Cu. Generally, the average concentration of the trace metals are below international guideline values for environmental quality criteria. Keywords: heavy metal, soil, enrichment factor (EF), geo-accumulation index (Igeo), contamination / pollution index

A Progress Report on the Center for Agricultural and Economic Development - The Center... What Has It Done?

The center for Agricultural and Economic Development was established eight years ago in response to concern over agricultural income problems. Since then, it has engaged in a variety of educational and research activities on behalf of farm families