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1.
Abstract. A technique for fine-scale vegetation mapping with the aid of low-altitude aerial photography was developed. The procedure is as follows: 1. The site is divided into a lattice pattern - in case the site is too large to fit into a single photograph with satisfactory resolution. The coordinates of every lattice point are surveyed to be used as control points for geometric correction. A photograph of each block of the lattice is taken using a remote-controlled camera system lifted by a captive helium balloon. 2. The vegetation is classified on the basis of a phytosociological survey. 3. The shapes and locations of vegetation patches appearing in the photographs are entered into a computer, using a digitizer. A geometric correction is carried out through coordinate transformation referring to the coordinates of the control points and subsequently a draft vegetation map is produced. Finally, discrepancies are corrected and the map is coloured to produce the final version of the vegetation map. This technique was applied to vegetation mapping at a bar, 500 m wide and 2 km long, in the river Yoshino in Shikoku, Japan. A fine-scale vegetation map was obtained and used to analyse the influence of plants on geomorphic processes and community-specific hydrogeomorphic conditions on the bar. 相似文献
2.
RNA- and DNA-synthesizing activities were much lower in conjugatingand zygote cells than in vegetatively growing cells. We suggestthat a certain factor(s) which may repress RNA and DNA Syntheseswas formed during the conjugation process. (Received December 24, 1971; ) 相似文献
3.
K Ono T Takii K Onozaki M Ikawa M Okabe M Sawada 《Biochemical and biophysical research communications》1999,262(3):610-614
Bone marrow transplantation with GFP-expressing cells from GFP-transgenic mice resulted in migration of GFP-positive cells into peripheral tissues and brain parenchyma. Most of these cells were observed as colony-like clusters. GFP-positive clusters in the brain were stained by antibody for ER-MP12, but those in the peripheral tissues were not. Since ER-MP12 antigen has been reported as a marker for murine early-stage myeloid precursor, this might suggest that some parts of phagocytic cells in the brain parenchyma such as microglia are derived from undifferentiated pluripotent hematopoietic cells. 相似文献
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Comparison of the Virulence of Methicillin-Resistant and Methicillin-Sensitive Staphylococcus aureus
Sadao Mizobuchi Junzaburo Minami Fu Jin Osamu Matsushita Akinobu Okabe 《Microbiology and immunology》1994,38(8):599-605
The virulence of methicillin-resistant Staphylococcus aureus (MRSA) was compared with that of methicillin-sensitive S. aureus (MSSA), using 13 MRSA and 7 MSSA strains isolated from clinical specimens. The infectivity and lethality of the two groups were examined as to the inoculum required to infect 50% of guinea pigs (ID50) and to kill 50% of mice (LD50), respectively. The mean ID50 [log10 colony forming units (CFU)] for MRSA strains was 7.1 ± 0.60 standard deviation, which was 1.5 higher than that for MSSA strains (P < 0.001). The mean LD50 (log10 CFU) for MRSA strains was 9.0 ± 0.42, being 1.1 higher than that for MSSA strains (P = 0.001). Pretreatment of mice with cyclophosphamide decreased the mean LD50 for MRSA strains more than that for MSSA strains, resulting in the difference in the mean LD50 being insignificant (P = 0.502). These results indicate that MRSA is less virulent than MSSA in normal hosts, but that they are equally virulent in immunocompromised hosts. The growth of MRSA strains was much slower than that of MSSA strains in the lag phase, although their growth rates were almost the same in the exponential growth phase, suggesting that the difference in virulence between them may be at least partly due to such a difference in growth. 相似文献
7.
Epidermal cysts are the benign tumors which are found in various regions. We experienced a rare case in which the preauricular sinus was the origin of the epidermal cyst. 相似文献
8.
Uchii Kimiko Wakimura Kei Kikko Takeshi Yonekura Ryuji Kawaguchi Riho Komada Honoka Yamanaka Hiroki Kenzaka Takehiko Tani Katsuji 《Limnology》2022,23(1):49-56
Limnology - Gnathopogon caerulescens is an endangered but commercially important fish in Lake Biwa, Japan. The population size of G. caerulescens has drastically reduced in the past decades, and... 相似文献
9.
Physiological characterization of anaerobic ammonium oxidizing bacterium ‘Candidatus Jettenia caeni’ 下载免费PDF全文
Muhammad Ali Mamoru Oshiki Takanori Awata Kazuo Isobe Zenichiro Kimura Hiroaki Yoshikawa Daisuke Hira Tomonori Kindaichi Hisashi Satoh Takao Fujii Satoshi Okabe 《Environmental microbiology》2015,17(6):2172-2189
To date, six candidate genera of anaerobic ammonium‐oxidizing (anammox) bacteria have been identified, and numerous studies have been conducted to understand their ecophysiology. In this study, we examined the physiological characteristics of an anammox bacterium in the genus ‘Candidatus Jettenia’. Planctomycete KSU‐1 was found to be a mesophilic (20–42.5°C) and neutrophilic (pH 6.5–8.5) bacterium with a maximum growth rate of 0.0020 h?1. Planctomycete KSU‐1 cells showed typical physiological and structural features of anammox bacteria; i.e. 29N2 gas production by coupling of 15NH4+ and 14NO2?, accumulation of hydrazine with the consumption of hydroxylamine and the presence of anammoxosome. In addition, the cells were capable of respiratory ammonification with oxidation of acetate. Notably, the cells contained menaquinone‐7 as a dominant respiratory quinone. Proteomic analysis was performed to examine underlying core metabolisms, and high expressions of hydrazine synthase, hydrazine dehydrogenase, hydroxylamine dehydrogenase, nitrite/nitrate oxidoreductase and carbon monoxide dehydrogenase/acetyl‐CoA synthase were detected. These proteins require iron or copper as a metal cofactor, and both were dominant in planctomycete KSU‐1 cells. On the basis of these experimental results, we proposed the name ‘Ca. Jettenia caeni’ sp. nov. for the bacterial clade of the planctomycete KSU‐1. 相似文献
10.
Akiko Takasuga Kunio Sato Ryouichi Nakamura Yosuke Saito Shinji Sasaki Takehito Tsuji Akio Suzuki Hiroshi Kobayashi Tamako Matsuhashi Koji Setoguchi Hiroshi Okabe Toshitake Ootsubo Ichiro Tabuchi Tatsuo Fujita Naoto Watanabe Takashi Hirano Shota Nishimura Toshio Watanabe Makio Hayakawa Yoshikazu Sugimoto Takatoshi Kojima 《PLoS genetics》2015,11(8)
Recessive skeletal dysplasia, characterized by joint- and/or hip bone-enlargement, was mapped within the critical region for a major quantitative trait locus (QTL) influencing carcass weight; previously named CW-3 in Japanese Black cattle. The risk allele was on the same chromosome as the Q allele that increases carcass weight. Phenotypic characterization revealed that the risk allele causes disproportional tall stature and bone size that increases carcass weight in heterozygous individuals but causes disproportionately narrow chest width in homozygotes. A non-synonymous variant of FGD3 was identified as a positional candidate quantitative trait nucleotide (QTN) and the corresponding mutant protein showed reduced activity as a guanine nucleotide exchange factor for Cdc42. FGD3 is expressed in the growth plate cartilage of femurs from bovine and mouse. Thus, loss of FDG3 activity may lead to subsequent loss of Cdc42 function. This would be consistent with the columnar disorganization of proliferating chondrocytes in chondrocyte-specific inactivated Cdc42 mutant mice. This is the first report showing association of FGD3 with skeletal dysplasia. 相似文献