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Mice with the K644E kinase domain mutation in fibroblast growth factor receptor 3 (Fgfr3) (EIIa;Fgfr3(+/K644E)) exhibited a marked enlargement of the brain. The brain size was increased as early as E11.5, not secondary to the possible effect of Fgfr3 activity in the skeleton. Furthermore, the mutant brains showed a dramatic increase in cortical thickness, a phenotype opposite to that in FGF2 knockout mice. Despite this increased thickness, cortical layer formation was largely unaffected and no cortical folding was observed during embryonic days 11.5-18.5 (E11.5-E18.5). Measurement of cortical thickness revealed an increase of 38.1% in the EIIa;Fgfr3(+/K644E) mice at E14.5 and the advanced appearance of the cortical plate was frequently observed at this stage. Unbiased stereological analysis revealed that the volume of the ventricular zone (VZ) was increased by more than two fold in the EIIa;Fgfr3(+/K644E) mutants at E14.5. A relatively mild increase in progenitor cell proliferation and a profound decrease in developmental apoptosis during E11.5-E14.5 most likely accounts for the dramatic increase in total telecephalic cell number. Taken together, our data suggest a novel function of Fgfr3 in controlling the development of the cortex, by regulating proliferation and apoptosis of cortical progenitors.

Abstract-Rotating coil probes are essential for measuring harmonic multipole fields of accelerator magnets. A fundamental requirement of these probes is their accuracy -which typically implies that the probes need to be very stiff and straight, have highly accurate knowledge of the placement of windings, and an ability to buck the fundamental fields well in order to supress the effects of vibrations. Ideally, for an R&D test environment, probe fabrication should also be easy and low-cost, so that probe parameters (type, length, number of turns, radius, etc.) can be customized to the magnet requiring test. Such facility allows measurement optimization for magnets of various multi-polarity, aperture size, cable twist pitch, etc. The accuracy and construction flexibility aspects of probe development, however, are often at odds with each other. This paper reports on application of printed-circuit board (PCB) and fused-deposition modelling (FDM) technologies, andwhat these offer in the fabrication of magnetic measurement probe systems. In particular, this paper describes a general purpose, self-contained, rotating coil device known as the 'ferret', and several other measurement probes -including two built for use at LBNL for the LARP HQ and LBNL HD programsconstructed using these techniques. Data from these devices as they have been used to measure superconducting dipole and quadrupole magnets at high fields are also presented and discussed.

Abstract-The US LHC Accelerator Research Program (LARP)and CERN combined their efforts in developing Nb3Sn magnets for the High-Luminosity LHC upgrade. The ultimate goal of this collaboration is to fabricate large aperture Nb3Sn quadrupoles for the LHC interaction regions (IR). These magnets will replace the present 70 mm aperture NbTi quadrupole triplets for expected increase of the LHC peak luminosity by a factor of 5. Over the past decade LARP successfully fabricated and tested short and long models of 90 mm and 120 mm aperture Nb3Sn quadrupoles. Recently the first short model of 150 mm diameter quadrupole MQXFS was built with coils fabricated both by the LARP and CERN. The magnet performance was tested at Fermilab's vertical magnet test facility. This paper reports the test results, including the quench training at 1.9 K, ramp rate and temperature dependence studies. Index Terms-Accelerator magnets, large hadron collider, Nb3Sn coils, superconducting magnets