Fourier-transform spectral imaging: retrieval of source information from three-dimensional spatial coherence

A method is described for efficiently obtaining the comprehensive information of a polychromatic radiator. Under certain conditions both the spatial and spectral details of the radiative object can be recovered simultaneously from the three-dimensional spatial coherence function in the diffraction region. The recovery of object information is based on a Fourier-transform relationship derived from the basic formula [E. Wolf and W. H. Carter, J. Opt. Soc. Am. 68, 953-964 (1978)] describing the field correlation function in terms of the source correlation function. A new type of interferometer is proposed for the efficient collection of the spatial coherence data. Experimental results of the spectral-image recovery are also presented

Proposal for measuring magnetism with patterned apertures

We propose a magnetic measurement method utilizing a patterned post-sample aperture in a transmission electron microscope. While utilizing electron magnetic circular dichroism, the method circumvents previous needs to shape the electron probe to an electron vortex beam or astigmatic beam. The method can be implemented in standard scanning transmission electron microscopes by replacing the spectrometer entrance aperture with a specially shaped aperture, hereafter called ventilator aperture. The proposed setup is expected to work across the whole range of beam sizes -- from wide parallel beams down to atomic resolution magnetic spectrum imaging.Comment: 6 pages, 4 figure

Immunohistochemical Comparison of Ontogenic Development of Bone Marrow Hematopoiesis in Two Different Ossification Systems

It is well known that the body skeleton is formed by two different types of ossification systems, endochondoral and intramembranous ossification. Bone marrow is the main site of active hematopoiesis after the formation of the bone marrow cavities. However, it is unclear whether the hematopoiesis in the bone marrow of two types of ossification is regulated by the same system or not. In this study, we focused on the ontogenic development of bone marrow hematopoiesis in two different ossification systems using mouse humeral bones and palatal process of maxillary bones. Immunohistochemical and RT-PCR analyses were performed to examine the development of hematopoiesis and the expression of cytokines related to hematopoiesis in the forming bone marrow (16-days gestation stage to 1-day postnatal stage). Immunohistochemical studies showed the sequential difference of hematopoiesis between two different ossification systems. In humeral bone marrow, granulopoiesis appeared first at E16, followed by erythropoiesis from E17. On the contrary, erythropoiesis preceded one day in the maxillary bone marrow at E18, one day before the detection of granulopoiesis. G-SCF and GM-CSF were expressed at every examined stage in both types of bones while M-CSF was not expressed in the humeral bone marrow at E16. Erythropoietin was detetcted in the endothelial cells and its expression was coincident with the onset of erythopoiesis. These results suggest the time kinetic and sequential differences of hematopoiesis in two different ossification systems, which might relate to the differences of hematopoietic microenvironment