31,608 research outputs found
Expression of the angular dependence of the quantum efficiency for a thin multi-alkali photocathode and its optical properties
The dependence of the quantum efficiency on the angle and polarization of the
incident photon needs to be formulated for a precise description of the
response of photomultiplier tubes. A simplified one-step model of photoelectron
emission was derived from Spicer's three-step model, and it enabled the
formulation of the dependence of the quantum efficiency in the visible range
for thin multi-alkali (NaKSbCs) photocathodes. The expression of the quantum
efficiency was proved by a measurement of the photocurrent for linearly
polarized light at various incident angles. Meanwhile, the measurement revealed
the complex refractive indices and thicknesses both of the stratified
photocathode and antireflection coating. It is indicated that the angular
dependence of the quantum efficiency is dictated by the optical properties of
the photocathode, which are discussed in detail on the basis of the obtained
parameters
Koszul duality for locally constant factorization algebras
Generalising Jacob Lurie's idea on the relation between the Verdier duality
and the iterated loop space theory, we study the Koszul duality for locally
constant factorisation algebras. We formulate an analogue of Lurie's
"nonabelian Poincare duality" theorem (which is closely related to earlier
results of Graeme Segal, of Dusa McDuff, and of Paolo Salvatore) in a symmetric
monoidal stable infinity category carefully, using John Francis' notion of
excision. Its proof depends on our earlier study of the Koszul duality for
E_n-algebras. As a consequence, we obtain a Verdier type equivalence for
factorisation algebras by a Koszul duality construction.Comment: 32 pages. Section 2.0 slightly simplified, References updated.
Comments welcome
Studies on reticuloendothelial system and hemaotpoiesis. I. Studies of extramedullary hematopoiesis
The author studied the hematopoietic disturbances of rabbit induced by saponin injection and drew the following conclusions: 1) By saponin injection, the structure of bone marrow is disintegrated and hematopoietic cells are released into the circulating blood forming extramedullary
hematopietic foci mainly in liver and spleen. The main attacking point of saponin should be RES. Recovery of hematopoietic foci is associated with the recovery of RES. The most marked extramedullary hematopoiesis is found three days after the injection. Thereafter, bone-marrow hematopoiesis proceeds to recovery stage, during which hematopoietic foci in liver and spleen are preserved, especially those in spleen persist fairly for a long time.
2) Daily injections of India ink kept up over a long period of time after the treatment with saponin, prevent the recovery of anemia and bone-marrow hematopoiesis. The lymph nodes, whose RES escaped from the severe damage
by India ink, keep the hematopoietic foci for a long time.
3) As far as hematopoiesis is concerned, there seems to be no functional differentiation among RE cells, though they seem to have a special function according to the organs to which they belong, e. g. antibody formation in lymph
apparatus, hematopoiesis in bone marrow and red cell destruction in spleen.</p
A New Proof of P-time Completeness of Linear Lambda Calculus
We give a new proof of P-time completeness of Linear Lambda Calculus, which
was originally given by H. Mairson in 2003. Our proof uses an essentially
different Boolean type from the type Mairson used. Moreover the correctness of
our proof can be machined-checked using an implementation of Standard ML
Studies on reticuloendothelial system and hemato-poiesis, III. Relationship between differentiation of erythroblast and oxygen tension
For the purpose to clarify the control mechanism of erythroid cell differentiation, the author observed morphologic changes in bone-marrow cells and circulating
red cells in phenylhydrazine anemia of rabbits by introducing a mass of red cells into vein at one time and reached the following conclusions. 1. After red cell transfusion in a mass to animal showing a marked hematopoietic activity, anisocytosis or macrocytosis becomes distinct with the appearance of big reticulocytes and red cells as large as four times the normal in
volume. This suggests, judging from their volume, the accelerated denucleation of erythroblast as early as at the late basophilic stage. 2. Observations on bone marrow at this stage revealed the reduction in the number of erythroblasts of undifferentiated type with the increase of rather differentiated ones. In erythroid islet, undifferentiated cells are found surrounding
a reticulum cell located in the center, while well differentiated ones in the outskirt area are situated near the sinusoid. Such a cell arrangement suggests that the erythroid cell requires a high oxygen tension for its differentiation. 3. From these observations and other results obtained from the studies on reticulocyte maturation and RNA synthesis of erythroblast, the author stresses that erythroid cells can differentiate as long as it is provided with a certain level of oxygen, even though it may develop m-RNA for differentiation. In other words, there should be two steps in the differentiation of erythroblast, the first is m-RNA synthesis induced by the information and the second is the somatic
protein synthesis with oxygen supply. This seems to be directly connected to the control mechanism of hematopoiesis by oxygen.</p
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