Radial Views Research Articles

ICP発光分光分析法における光取り出し方向の違いによる測光感度比較と鉄鋼中の微量ヒ素,アンチモン及びスズの定量

ICP発光分光分析法における光取り出し方向の違いによる測光感度比較と鉄鋼中の微量ヒ素,アンチモン及びスズの定量

Substance P-immunoreactive neurons in the human retina.

Substance P (SP) is a neuropeptide that acts as a neurotransmitter or a neuromodulator in the retina. The aim of this study was to identify the type(s) and the distribution of the SP-immunoreactive (SP-IR) cells in the human retina. We have used an antiserum to SP to immunostain neurons in postmortem human retinae. Immunostained retinae were processed with the avidin-biotin complex (ABC) to visualize the cells either whole mounted in glycerol or embedded in plastic. Some retinae were also sectioned at 20 microns in order to obtain radial views of stained cells. SP-IR amacrine cells stain intensely and appear to be of a single type in the human retina. They are large-field cells with large cell bodies (16 microns diameter) lying in normal or displaced positions on either side of the inner plexiform layer (IPL). Their sturdy, spiny, and appendage-bearing dendrites stratify in stratum 3 (S3) of the IPL, where many overlapping, fine dendrites intermingle to form a plexus of stained processes. Either cell bodies or primary dendrites emit an "axon-like" process that, typically, divides into two long, fine processes, which run in opposite directions for hundreds of micrometers in S5 and S3 before disappearing as distinct entities in the stained plexus in S3. Long, fine dendrites also pass from the dendritic plexus to run in S5 and down to the nerve fiber layer to end as large varicosities at blood vessel walls. In addition, fine processes are emitted from the dendritic plexus that runs in S1, and some pass up to the outer plexiform layer (OPL) to run therein for short distances. The SP-IR amacrine cell has many similarities to the thorny, type 2 amacrine cells described from Golgi studies. In addition to the SP-IR amacrine cells, a presumed ganglion cell type is faintly immunoreactive. Its 20-22 microns cell body gives rise to a radiate, sparsely branched, wide-spreading dendritic tree running in S3. Its dendrites and cell body become enveloped by the more intensely SP-IR processes and boutons from the SP-IR amacrine cell type. The SP-IR ganglion cell type most resembles G21 from a Golgi study.

Freeze‐fracturing for low‐temperature scanning electron microscopy of Hartig net in synthesized Picea abies–Hebeloma crustuliniforme and –Tricholoma vaccinum ectomycorrhizas *

SUMMARYRapidly frozen ectomycorrhizal roots were freeze‐fractured under high vacuum in a dedicated cryo‐preparation unit and investigated in the frozen, partially freeze‐dried, or fully hydrated state. Tangential, radial and occasional transverse surface views of Hartig net were obtained after freeze‐fracturing. Protoplasmic and exoplasmic fracture faces of the fungal plasmalemma und occasional fractures between the fungal cell wall and the extracellular matrix were seen. Primary pit‐fields with plasmodesmata occurred in non‐ectomycorrhizal parts of the root as well as in small gaps of Hartig net. Septa with dolipores were observed in the finger‐like complexes of the Hartig net.

Spatially resolved EUV emission from focused REB discharges into thin targets

The EUV emission from 10- to 100-mg/cm2-thick planar targets (Z=6–79) exposed to 60-nsec-duration focused relativistic electron beams was examined at current densities of 0.4–1.0 MA/cm2. Spatially resolved spectra were obtained with a stigmatic near-normal incidence spectrograph, in the wavelength range 500–2100 Å, along axial and radial directions. Time-resolved EUV data were obtained with windowless photoelectric diodes operated unfiltered and filtered with 0.5-μm-thick aluminum. The axial views show copious emission from the diode gap associated with late-time impedance collapse. Radial views show continuum radiation which is emitted from the region of the target exposed to the focused REB and line radiation which originates from a lower-density (approximately 1019 cm−3) more-extended late-time plasma resulting from foil expansion. The region of the foil exposed to the focused REB radiates as a blackbody source with a peak temperature of 2–6 eV. These temperatures are a factor of 2 below the calculated temperatures for classical deposition in the foils exposed to the focused beam assuming no hydrodynamic foil expansion.