Multipotent stem cells are thought to be responsible for the generation of new neurons in the adult brain. Neurogenesis also occurs in an accessible part of the nervous system, the olfactory mucosa. We show here that cells from human olfactory mucosa generate neurospheres that are multipotent in vitro and when transplanted into the chicken embryo. Cloned neurosphere cells show this multipotency. Multipotency was evident without prior culture in vitro: cells dissociated from adult rat olfactory mucosa generate leukocytes when transplanted into bone marrow-irradiated hosts, and cells dissociated from adult mouse olfactory epithelium generated numerous cell types when transplanted into the chicken embryo. It is unlikely that these results can be attributed to hematopoietic precursor contamination or cell fusion. These results demonstrate the existence of a multipotent stem-like cell in the olfactory mucosa useful for autologous transplantation therapies and for cellular studies of disease. Developmental Dynamics 233:496 -515, 2005.

We perform a new analysis of electron-proton scattering data to determine the proton electric and magnetic radii, enforcing model-independent constraints of form factor analyticity. A wide-ranging study of possible systematic effects is performed. An improved analysis is developed that rebins data taken at identical kinematic settings, and avoids a scaling assumption of systematic errors with statistical errors. Employing standard models for radiative corrections, our improved analysis of 2010 Mainz A1 collaboration data yields a proton electric radius rE = 0.895(20) fm and magnetic radius rM = 0.776(38) fm. A similar analysis applied to world data (excluding Mainz data) implies rE = 0.916(24) fm and rM = 0.914(35) fm. The Mainz and world values of the charge radius are consistent, and a simple combination yields a value rE = 0.904(15) fm that is 4σ larger than the CREMA muonic hydrogen determination. The Mainz and world values of the magnetic radius differ by 2.7σ, and a simple average yields rM = 0.851(26) fm. The circumstances under which published muonic hydrogen and electron scattering data could be reconciled are discussed, including a possible deficiency in the standard radiative correction model which requires further analysis.

We determine the nucleon electromagnetic form factors and their uncertainties from world electron scattering data. The analysis incorporates two-photon exchange corrections, constraints on the low-Q2 and high-Q2 behavior, and additional uncertainties to account for tensions between different data sets and uncertainties in radiative corrections.Comment: 9 pages, 7 figures. Published on Phys. Lett.