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The crop water stress index is receiving significant attention these days, especially in arid and semiarid regions, for quantifying water stress and effective irrigation scheduling. Nowadays, machine learning techniques such as neural networks are being widely used to determine CWSI. In the present study, Self-Organizing Maps (SOM) and Feed Forward-Back Propagation Artificial Neural Networks (FF-BP-ANN) are compared while determining the CWSI of rice crop. Irrigation field experiments with varying degrees of irrigation were conducted at the irrigation field laboratory of the Indian Institute of Technology, Roorkee, during the growing season of the rice crop. The CWSI of rice was computed empirically by measuring key meteorological variables (relative humidity, air temperature, and canopy temperature). The empirically computed CWSI was compared with SOM and FF-BP-ANN predicted CWSI. For the lower CWSI baseline of rice, a linear relationship between air and canopy temperature difference (Tc-Ta) and, air vapour pressure deficit (AVPD) was developed, whereas air temperature plus 3°C was taken for the upper CWSI baselines. The performance of SOM and FF-BP-ANN were compared by computing Nash–Sutcliffe efficiency (NSE), index of agreement (d), root mean squared error (RMSE), and coefficient of correlation (R2). It is found that FF-BP-ANN (R2 = 0.97, NSE = 0.92, d = 0.95, RMSE = 0.006) performs better than SOM (R2 = 0.88, NSE = 0.87, d = 0.9, RMSE = 0.075). [ABSTRACT FROM AUTHOR]

Inverse problem of determining unsaturated soil hydraulic properties from transient infiltration and internal drainage events are analyzed. Hydraulic properties are assumed to be described by van Genuchten's relationships. The inverse problem is solved using Levenberg-Marquardt method while the forward problem is solved using a mass conservative finite difference numerical scheme. The bias induced by different objective functions on the parameter estimates with error free and noisy data are analyzed. Field experiments are conducted at two sites to compare the parameter estimates obtained from the infiltration and internal drainage tests. The results indicate that some objective functions induce undue bias in the estimated parameters in the presence of noise in the data and as such selecting a suitable objective function should be given due importance in the parameter estimation. The comparison of the parameter estimates from infiltration and internal drainage experiments at two sites indicates that the parameter estimates are close to each other. It is concluded that infiltration experiment, which is simpler and of short duration can be an alternative to internal drainage experiment for estimating the unsaturated soil parameters. DOI: 10.1061/(ASCE)IR.1943-4774.0000234 CE Database subject headings: Least squares method; Parameters; Data processing; Errors; Draining; Hydraulic properties. Author keywords: Unsaturated zone; Least-squares minimization; Parameter estimation; Data errors.

Soil-water movement due to root-water uptake, is a key process for plant growth and transport of water in the soil plant system. There are different root-water uptake models to determine the extraction rate of soil moisture by roots. The present study examines the performance of different root-water extraction models using available data as well as data generated under controlled conditions. Data pertaining to moisture uptake in respect to two crops: wheat (Triticum aestivum L.) and maize (Zea mays L.) along with soil-water characteristics have been monitored at the Indian Institute of Technology Roorkee, agricultural farm. For this purpose, a numerical model is also formulated by incorporating different moisture extraction terms as sink terms in the Richards equation. A nonlinear root-water uptake model selected as the base model was evaluated for its moisture uptake efficiency. The work establishes the merits of the base model over other extraction terms considered, particularly constant and linear extraction terms in predicting the soil moisture depletion in the root zone. The work stresses the nonlinearity parameter of the base model, which is capable of defining crop specific nonlinearity in the plant moisture uptake. DOI: 10.1061/(ASCE)IR.1943-4774.0000067 CE Database subject headings: Soil water; Crops; Irrigation; Evapotranspiration; Water use; Simulation models.

The experimental work reported here is a validation of Langmnir probe measurements against emission spectroscopic and discharge resistivity measurements of atmospheric glow discharge plasma parameters. The probe measurements of plasma density are close to that obtained by spectroscopy and discharge resistivity measurement. However, it is found that the electron temperature measurement by the probe is higher than that obtained by the spectroscopic technique. Variation of plasma parameters with operating voltage and frequency, which are estimated by the three techniques, shows a similar trend. Index Terms--Atmospheric pressure glow discharge (APGD), discharge resistivity, helium line intensity ratios, Langmuir probe, plasma stealth.

Presented herein is a procedure for arriving at an optimal design of a homogeneous earth dam laid on an impervious foundation and provided with a drain. The procedure, heavily dependent on variably saturated flow modeling, involves optimizing a multiobjective function comprising a weighted summation of four objective functions, viz., the dam section area, seepage discharge, wetted area of the dam section and the drain area. The design variables considered in the optimization are the upstream and downstream slopes and the drain dimensions. The optimization is carried out subject to the constraints ensuring safe upstream and downstream slopes and sufficient distance between the free surface and the downstream face. Two of the objective functions (viz., the seepage discharge and the wetted area) and the constraints are implicit functions of the design variables. Their values are obtained by employing a numerical model of two-dimensional (vertical plane) variably saturated flow in a homogeneous earth dam. Optimization, conducted by the sequential unconstrained minimization technique procedure is preceded by several runs of the model for various combinations of the design variables. The discrete values of the implicit functions so generated are invoked during optimization to compute the implicit objective functions and constraints. The results are presented in the form of nondimensional design tables/curves. The design procedure is illustrated with the help of few examples. DOI: 10.1061/(ASCE)0733-9437(2007)133:2(116) CE Database subject headings: Seepage; Optimization; Dams, earth; Dam foundations; Drainage.

Enzymes of the blood coagulation pathway enhance the inflammatory response leading to endothelial dysfunction, accounting, in part, for the vascular complications occurring in sepsis and cardiovascular disease. The responses of endothelial cell activation include induction of the expression of tissue factor (TF), a membrane glycoprotein that promotes thrombosis, and of E-selectin, a cell adhesion molecule that promotes inflammation. In this report, we demonstrate synergistic interactions between the coagulation factor Xa (fXa) and the proinflammatory cytokines TNF, IL-1[beta], and CD40L, leading to enhanced expression of TF and E-selectin in endothelial cells. A detailed analysis of the molecular pathways that could account for this activity of fXa showed that fXa inhibited the cytokine-induced expression of dual specificity phosphatases, MAP kinase phosphatase-L, -4, -5, and -7, blocking a negative regulatory effect on c-Jun N-terminal kinase. The synergistic interaction between fXa and TNF was also involved in the inhibition of A20 and I[[kappa]B[alpha] expression in the I[kappa]B kinase-NF-[kappa]B pathway. The data indicate that inhibition of negative regulatory signaling accounts for the amplification of cytokine-induced endothelial cell activation by fXa. cytokines | endothelial cells | factor Xa | inflammation

Primary malignant fibrous histiocytoma (MFH) of the central nervous system (CNS) is uncommon. We report cases of two young patients of MFH arising from the cranial meninges and involving the [...]

We earlier reported that the soluble form of the CD40 ligand (sCD40L), is involved in thrombosis by stabilizing platelet thrombi. In this article, we have determined the mechanism by which this protein affects platelet biology. Addition of sCD40L to washed platelets was found to activate the receptor function of [[alpha].sub.llb][[beta].sub.3] as measured by the induction of fibrinogen binding and the formation of platelet microparticles. Mutation in the KGD sequence (D117E) of sCD40L, the [[alpha].sub.IIb][[beta].sub.3]-binding domain in the N terminus of the protein resulted in a loss of the platelet-stimulatory activity of this protein. Integrilin, a [[alpha].sub.IIb][[beat].sub.3] antagonist, but not an antibody to CD40 that blocked the ligand-binding activity, inhibited these platelet-stimulatory events. CD[40.sup.-/-] platelets bound fibrinogen and formed microparticles similar to WT platelets, again indicating that CD40 is not involved in sCD40L-induced platelet activation. Exposure of platelets to sCD40L, but not D117E-sCD40L-coated surfaces, induced platelet thrombi formation under arterial shear rate. sCD40L-induced platelet stimulation resulted in the phosphorylation of tyrosine-759 in the cytoplasmic domain of [[beta].sub.3]. Platelets from the diYF mouse strain, expressing [[beta].sub.3] in which both cytoplasmic tyrosines are mutated to phenylalanine, were defective in sCD40L-induced platelet stimulation. These data indicate that sCD40L is a primary platelet agonist and that platelet stimulation is induced by the binding of the KGD domain of sCD40L to [[alpha].sub.IIb][[beta].sub.3], triggering outside-in signaling by tyrosine phosphorylation of [[beta].sub.3].