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We present direct observation of vortices confined to a superconducting 4 ϫ 4 m 2 square Pb film at 4.2 K with a high resolution scanning Hall probe microscope. Integrals of the magnetic field penetrating the square as a function of the applied field show that an applied-field dependence of vorticity L agrees with calculations based on the Ginzburg-Landau ͑GL͒ equation for a square sample geometry. From asymmetric field distribution of the confined magnetic flux, the locations of vortices on the square are inferred for vorticities L =1-5. The obtained vortex patterns are analogous with the calculations in the framework of the full GL equation for temperatures considerably lower than the superconducting transition temperature T c .The geometry of superconducting samples ͑circular, triangular, square, etc.͒ fully defines the symmetry of the vortex patterns when the superconducting order parameter can be well described by the linearized version of the GinzburgLandau ͑GL͒ theory. 1-4 Among others, peculiar vortex patterns including a giant vortex 5,6 and an antivortex 3 can be realized in superconducting microstructures. The vortex patterns vary with the applied field, accompanying the oscillation of the superconducting transition temperature as a function of the magnetic field, T c ͑H͒. This oscillation has been observed in resistivity measurements and they give indirect experimental evidence for the formation of the symmetryinduced vortex patterns. 3,4 However, vortex visualization experiments have not given a sufficient direct evidence yet.A few groups 7,8 have applied imaging techniques to visualization of vortex states in superconducting microstructures. Earlier, scanning supperconducting quantum interference device microscopy 7 has shown that vortex configurations in 30-50 m sized Nb films with triangular and square forms are not exactly the same as the theoretical prediction. Bitter decoration results 8 indicate that vortices form shell structures 9 in 1-4 m sized Nb disks, while triangular and square Nb films have no stable vortex configurations. Nb films have typically the strong pinning property, so that metastable states produced by strong pinning can easily destroy symmetry-induced vortex patterns. In addition, small coherence length ͑0͒ ͑ϳ10 nm͒ of a Nb film might make it difficult to see stable vortex patterns because a theory requests that should be above ϳ0.1a, 10 where a is a sample dimension: the stability of vortex patterns is expected above / a ϳ 0.1. We now propose to study vortex configurations in superconducting Pb microstructures with a low pinning ͑the critical current j c is considerably smaller than that of Nb films͒ and relatively large ͑0͒ ͓it has been reported to be 96 nm in bulk Pb ͑Ref. 11͔͒. In order to look at vortex configurations in the Pb sample, we use a scanning Hall probe microscope ͑SHPM͒ with a high spatial resolution. In this Brief Report, we present scanning Hall probe microscopy results for a 4 ϫ 4 m 2 Pb microsquare, in which vortex patterns inferred from multimonopole fi...

Genetic parameters for chronic progressive lymphedema (CPL)-associated traits in Belgian Draught Horses were estimated, using a multitrait animal model. Clinical scores of CPL in the four limbs/horse (CPLclin ), skinfold thickness and hair samples (hair diameter) were studied. Due to CPLclin uncertainty in younger horses (progressive CPL character), a restricted data set (D_3+) was formed, excluding records from horses under 3 years from the complete data set (D_full). Age, gender, coat colour and limb hair pigmentation were included as fixed, permanent environment and date of recording as random effects. Higher CPLclin certainty (D_3+) increased heritability coefficients of, and genetic correlations between traits, with CPLclin heritabilities (SE) for the respective data sets: 0.11 (0.06) and 0.26 (0.05). A large proportion of the CPLclin variance was attributed to the permanent environmental effect in D_full, but less in D_3+. Date of recording explained a proportion of variance from 0.09 ± 0.03 to 0.61 ± 0.08. Additive genetic correlations between CPLclin and both skinfold thickness and hair diameter showed the latter two traits cannot be used as a direct diagnostic aid for CPL. Due to the relatively low heritability of CPLclin , selection should focus on estimated breeding values (from repeated clinical examinations) to reduce CPL occurrence in the Belgian Draught Horse.

The objective of this review was to summarise and evaluate the current state of knowledge about chronic progressive lymphoedema in draught horses. Clinical signs of this multifactorial disorder are mainly restricted to the lower limbs, comprising progressively deteriorating skin, swelling and deformation. Although typical lesions were first reported at the beginning of the 20th century, chronic progressive lymphoedema was recognised as a specific syndrome only in 2003, and since then research has driven forward. Despite the high prevalence in some breeds and the serious economic impact, the pathogenesis is not fully understood, and the available treatment options remain symptomatic and noncurative. There is a need to improve diagnostic techniques and to develop selection tools.

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Cranial nerve lessions often accompany head trauma. Nevertheless, isolated involvement of the sixth nerve without any cranial or cervical fracture is rare. Nerve injury could occur at the sites of the dural entry points and at the petrous apex during down- or upward movement of the brain caused by violent linear force to the head. Management is symptomatic. Most cases improve within three months and many resolve by six months, but spontaneous recovery does not always occur. We describe the case of a 13-year-old boy who developed isolated abducens nerve palsy after closed head trauma.

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We study the vortex structure in a Pb film deposited on top of a periodic array of ferromagnetic square microrings by combining two high-resolution imaging techniques: Bitter decoration and scanning Hall-probe microscopy ͑SHPM͒. The periodicity and strength of the magnetic pinning potential generated by the square microrings are controlled by the magnetic history of the template. When the square rings are in the magnetized dipolar state, known as the onion state, the strong stray field generated at the domain walls prevents the decoration of vortices. SHPM images show that the stray field generated by the dipoles is much stronger than the vortex field, in agreement with the results of simulations. Real-space vortex imaging has revealed that in the onion state, the corners of the square rings act as effective pinning centers for vortices.