Towards Truly “Global” Near Infrared Calibrations for Protein and Neutral Detergent Fibre in Dried Ground Forages

Over the past five years, Foss and DeLaval have sponsored the activities of a group of forage analysts with the aim of developing global Near Infrared (NIR) calibrations for parameters that are important in ruminant nutrition. The approach adopted has been based on the amalgamation of historical databases from centres worldwide and calibrations for protein and neutral detergent fibre (NDF) in dried ground forages have been developed based on databases that currently comprise approximately 30,000 records. Protein and NDF, while not the most important parameters in ruminant nutrition, were chosen for the initial calibration development exercise because of the amount of data available and because the methodologies adopted by different laboratories worldwide were relatively uniform. The aim was to create calibrations that would work for any forage type in any area of the world. Over the past two years, several trials have been carried out worldwide comparing the performance of global calibrations with the performance of locally developed calibrations for indigenous forages and based on reference values from local laboratories

Nonlinear wave transmission and pressure on the fixed truncated breakwater using NURBS numerical wave tank

Fully nonlinear wave interaction with a fixed breakwater is investigated in a numerical wave tank (NWT). The potential theory and high-order boundary element method are used to solve the boundary value problem. Time domain simulation by a mixed Eulerian-Lagrangian (MEL) formulation and high-order boundary integral method based on non uniform rational B-spline (NURBS) formulation is employed to solve the equations. At each time step, Laplace equation is solved in Eulerian frame and fully non-linear free-surface conditions are updated in Lagrangian manner through material node approach and fourth order Runge-Kutta time integration scheme. Incident wave is fed by specifying the normal flux of appropriate wave potential on the fixed inflow boundary. To ensure the open water condition and to reduce the reflected wave energy into the computational domain, two damping zones are provided on both ends of the numerical wave tank. The convergence and stability of the presented numerical procedure are examined and compared with the analytical solutions. Wave reflection and transmission of nonlinear waves with different steepness are investigated. Also, the calculation of wave load on the breakwater is evaluated by first and second order time derivatives of the potential

Deletion of Exon 20 of the Familial Dysautonomia Gene Ikbkap in Mice Causes Developmental Delay, Cardiovascular Defects, and Early Embryonic Lethality

Familial Dysautonomia (FD) is an autosomal recessive disorder that affects 1/3,600 live births in the Ashkenazi Jewish population, and leads to death before the age of 40. The disease is characterized by abnormal development and progressive degeneration of the sensory and autonomic nervous system. A single base pair substitution in intron 20 of the Ikbkap gene accounts for 98% of FD cases, and results in the expression of low levels of the full-length mRNA with simultaneous expression of an aberrantly spliced mRNA in which exon 20 is missing. To date, there is no animal model for the disease, and the essential cellular functions of IKAP - the protein encoded by Ikbkap - remain unknown. To better understand the normal function of IKAP and in an effort to generate a mouse model for FD, we have targeted the mouse Ikbkap gene by homologous recombination. We created two distinct alleles that result in either loss of Ikbkap expression, or expression of an mRNA lacking only exon 20. Homozygosity for either mutation leads to developmental delay, cardiovascular and brain malformations, accompanied with early embryonic lethality. Our analyses indicate that IKAP is essential for expression of specific genes involved in cardiac morphogenesis, and that cardiac failure is the likely cause of abnormal vascular development and embryonic lethality. Our results also indicate that deletion of exon 20 abolishes gene function. This implies that the truncated IKAP protein expressed in FD patients does not retain any significant biological function

Stage-specific control of neural crest stem cell proliferation by the small rho GTPases Cdc42 and Rac1

The neural crest (NC) generates a variety of neural and non-neural tissues during vertebrate development. Both migratory NC cells and their target structures contain cells with stem cell features. Here we show that these populations of neural crest-derived stem cells (NCSCs) are differentially regulated by small Rho GTPases. Deletion of either Cdc42 or Rac1 in the NC results in size reduction of multiple NC target structures because of increased cell-cycle exit, while NC cells emigrating from the neural tube are not affected. Consistently, Cdc42 or Rac1 inactivation reduces self-renewal and proliferation of later stage, but not early migratory NCSCs. This stage-specific requirement for small Rho GTPases is due to changes in NCSCs that, during development, acquire responsiveness to mitogenic EGF acting upstream of both Cdc42 and Rac1. Thus, our data reveal distinct mechanisms for growth control of NCSCs from different developmental stages