407 research outputs found
An electron-microscopic study on lipogenesis
With the purpose to elucidate morphologically the site where fat synthesis takes place in the cell, electron-microscopic observation has been conducted on the interscapular brown fat tissue of mice at various periods of carbohydrate introduction after starvation. By starving mice, the depot lipids in the brown fat have been discharged almost completely, and the carbohydrate introduction has caused the biosynthesis of lipids from carbohydrtates in the same tissue. Observations on the tissues proved that the lipogenesis in the brown fat tissue cells takes place in the ground substance keeping the intimate correlation with the endoplasmic reticulum but not in the mitochondria.</p
Observed Features of Langmuir Turbulence Forced by Misaligned Wind and Waves Under Destabilizing Buoyancy Flux
Several features of Langmuir turbulence remain unquantified despite its potentially large impacts on ocean surface mixing. For example, its vertical velocity variance, expected to be proportional to based on numerical simulations, was proportional to in recent field observations, where is the friction velocity and is surface Stokes velocity. To investigate unquantified features of Langmuir turbulence, we conducted a field experiment around a marine observation tower in a shallow sea off the southern coast of Japan in early winter when winds and waves (often swells) were often misaligned. Coherent structures similar to Langmuir cells were successfully identified in the horizontal and vertical structures of turbulent flows measured with upward- and horizontally looking acoustic Doppler current profilers (ADCPs). ADCPs and several anemometers attached at the tower showed that turbulent vertical velocity variance was large when the Langmuir number and Hoenikker number (; where B is surface buoyancy flux and H is the water depth) were both small and that the orientation of the cells was generally aligned in the direction of Lagrangian current shear. These results agree well with the previous numerical results. As in the previous observations, however, the vertical velocity variance appeared to be proportional to . In our experiment, this curious feature was explained by compensatory effects between waves and convection. Misaligned wind with waves also seems to characterize the observed Langmuir turbulence, though further quantitative analysis is required to confirm this result
二分亀頭を伴った陰茎海綿体異物の1例
We had an opportunity to treat a rare case of foreign body in the corpus cavernosum in a patient with cleft glans penis. The foreign body was a 13 cm wire, which was inserted by the patient himself for masturbation, and was removed surgically. To our knowledge, such a case has never been reported in the literature
Cytochemical studies of the hemoglobin synthesis of erythroblasts
The process of hemoglobin sythesis in erythroid cells have been traced mainly by observing cells under the light of 4,060 Å. To scrutinize the theory of hemoglobin synthesis in the nucleus of erythroblasts, several
cytochemical and morphological observations were also carried out. The conclusions derived from them are as follows: 1 The absorption at 4,060 Å of the cell, which indicates the location of heme, appeared in the nucleus as early as in the develpmental stage of basophilic erythroblasts. The absorption of hcme in cytoplasm likewise appeared in this stage showing nearly the same intensity of the absorption. The absorption picture of heme in the nucleus, which is coincidental
with that of interchromatin, increased along with the progess of maturation as well as in the cytoplasm. The absorption in the nucleus disappeared at the orthochromatic stage where the picture of interchromatin
disappeared, while the intensity of absorption in the cytoplasm continued to increase till the stage of reticulocyte. 2 The pseudoperoxidase reaction of hemoglobin, the appearance of acidophlic protein and masked lipids detectable in the location of hemoglobin
gave an exactly identical picture with that of the absorption of heme in the nucleus as well as in the cytoplasm. 3 Permeability test performed by supravital staining with Nile blue revealed that the nucleus of erythroblasts from the basophilic to the orthorchromatic
stages has increased its permeability being stained selectively as in the case of dead cells. 4 The mitochondria and the endoplasmic reticulum proved to be
retained well in the entire course of hemoglobin synthesis, even after the denucleation, the reticulocyte stage. From these observations the authors believe that the hemoglobin syntheis will take place in the cytoplasm throughout the life cycle of erythroid cells, pointing out that the absorption picturebf heme appearing in the nucleus will be in all likelihood due to the infusion of the hemoglobin from the cytoplasm.</p
The brightest UV-selected galaxies in protoclusters at : Ancestors of Brightest Cluster Galaxies?
We present the results of a survey of the brightest UV-selected galaxies in
protoclusters. These proto-brightest cluster galaxy (proto-BCG) candidates are
drawn from 179 overdense regions of -dropout galaxies at from the
Hyper Suprime-Cam Subaru Strategic Program identified previously as good
protocluster candidates. This study is the first to extend the systematic study
of the progenitors of BCGs from to . We carefully remove
possible contaminants from foreground galaxies and, for each structure, we
select the brightest galaxy that is at least 1 mag brighter than the fifth
brightest galaxy. We select 63 proto-BCG candidates and compare their
properties with those of galaxies in the field and those of other galaxies in
overdense structures. The proto-BCG candidates and their surrounding galaxies
have different rest-UV color distributions to field galaxies and
other galaxies in protoclusters that do not host proto-BCGs. In addition,
galaxies surrounding proto-BCGs are brighter than those in protoclusters
without proto-BCGs. The image stacking analysis reveals that the average
effective radius of proto-BCGs is larger than that of field
galaxies. The color differences suggest that proto-BCGs and their
surrounding galaxies are dustier than other galaxies at . These results
suggest that specific environmental effects or assembly biasses have already
emerged in some protoclusters as early as , and we suggest that
proto-BCGs have different star formation histories than other galaxies in the
same epoch.Comment: 18 pages, 11 figures, Accepted for publication in Ap
米国における気候変動政策 : 米国および日韓の地球環境政策ネットワーク調査からの考察 (特集 地球環境政治と市民社会)
近年政治学では政策決定過程に及ぼすネットワークの役割に関心が集っている。本稿は米国環境政策ネットワーク調査を日韓の同調査と比較し、米国の特性を浮き彫りにする。これは広範な政策ネットワークの構造と機能を国際比較する白米独韓調査計画の中間報告である
Loss of Heterozygosity in Thyroid Tumors
We analyzed 53 loci on 21 chromosomes other than chromosome 4 to detect possible loss of heterozygosity in 31 thyroid tumors using polymorphic DNA markers that detect allelic deletions at specific chromosomal loci. Loss of heterozygosity on chromosomes 1, 7 and 12 was detected in one follicular thyroid adenoma, and on chromosome 1 in two medullary thyroid carcinomas. However, no loss of heterozygosity was detected at any of the loci examined in papillary thyroid carcinomas. These results suggest that chromosomal loss detected in thyroid adenoma is one of the signals for risk of premalignant transformation, and that inactivation of unknown genes on chromosome 1p contributes to tumorigenesis of medullary thyroid carcinoma. Some genetic changes other than chromosomal losses may participate in the tumorigenesis of papillary thyroid carcinoma
Interfamily Transfer of Dual NB-LRR Genes Confers Resistance to Multiple Pathogens
A major class of disease resistance (R) genes which encode nucleotide binding and leucine rich repeat (NB-LRR) proteins have been used in traditional breeding programs for crop protection. However, it has been difficult to functionally transfer NB-LRR-type R genes in taxonomically distinct families. Here we demonstrate that a pair of Arabidopsis (Brassicaceae) NB-LRR-type R genes, RPS4 and RRS1, properly function in two other Brassicaceae, Brassica rapa and Brassica napus, but also in two Solanaceae, Nicotiana benthamiana and tomato (Solanum lycopersicum). The solanaceous plants transformed with RPS4/RRS1 confer bacterial effector-specific immunity responses. Furthermore, RPS4 and RRS1, which confer resistance to a fungal pathogen Colletotrichum higginsianum in Brassicaceae, also protect against Colletotrichum orbiculare in cucumber (Cucurbitaceae). Importantly, RPS4/RRS1 transgenic plants show no autoimmune phenotypes, indicating that the NB-LRR proteins are tightly regulated. The successful transfer of two R genes at the family level implies that the downstream components of R genes are highly conserved. The functional interfamily transfer of R genes can be a powerful strategy for providing resistance to a broad range of pathogens
Do seabirds mated for life synchronize their migration timing and at-sea activity outside the breeding period? Tracking movement and behavior of Rhinoceros auklet pairs during the non-breeding and pre-laying periods
第6回極域科学シンポジウム[OB] 極域生物圏11月16日(月) 国立極地研究所1階交流アトリウ
How are fine sediments described in sediment sheet flow?
Stony debris flow transits to sediment sheet flow when the river bed gradient becomes gentle. The sediment sheet flow consists of a water flow layer and a sediment moving layer. Fine sediments are expected to behave as a part of the fluid rather than a solid phase in the sediment moving layer. Further, it can be thought that a part of fine sediment can be suspended in the water flow layer. However, it was not possible to physically express whether the fine sediment behaves as a solid phase or a fluid phase in the numerical simulation model. Here we physically modeled fine sediment behavior in sediment sheet flow. We confirmed the applicability of the new model to describe the longitudinal deposited sediment gradient in flume experiments
- …