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51.
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A new type of sampler for dry deposition in a forest canopy was designed and tested to confirm its usefulness. The new sampler
is made of Teflon chips packed in a nylon net, and tied on a rod like a branch in the canopy. The validity and characteristics
of the new sampler were checked by comparing it with the conventional bucket sampler and the foliar extraction method using
hinoki (Chamaecyparis obtusa) trees. The comparison between the deposited amounts on the dummy branch and those on the bucket indicates that the dummy
could trap gaseous matter more effective than the bucket. From a comparison with the foliar extracting method, it is concluded
that the trapping of particulate matter by the new dummy branch is comparable to that of natural needle leaves. However, its
efficiency for gaseous matter is relatively small. This disadvantage should be improved by applying other materials to the
dummy. Moreover, it is found that the uptake of gas especially SO2 through the stomata is an important point in the discussion about dry deposition. To evaluate the amounts of dry deposition
in the forest canopy more precisely, combination with the additional method should be useful.
This study was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science, Sports,
and Culture, Japan. 相似文献
54.
Yurimoto H Abe K Abe M Ebihara M Fujimura A Hashiguchi M Hashizume K Ireland TR Itoh S Katayama J Kato C Kawaguchi J Kawasaki N Kitajima F Kobayashi S Meike T Mukai T Nagao K Nakamura T Naraoka H Noguchi T Okazaki R Park C Sakamoto N Seto Y Takei M Tsuchiyama A Uesugi M Wakaki S Yada T Yamamoto K Yoshikawa M Zolensky ME 《Science (New York, N.Y.)》2011,333(6046):1116-1119
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid. 相似文献
55.
L G Wheaton H Rodriguez-Martinez P G Weston C H Ko B K Gustafsson 《American journal of veterinary research》1986,47(10):2205-2207
Spontaneous and drug-induced uterine motility (UM) was recorded in 5 nonanesthetized bitches for 2 to 4 days. Catheter-tip pressure transducers were surgically implanted in 1 uterine horn, tunneled subcutaneously to exit from the skin over the dorsal lumbar area, and protected by a bandage. On the day after implantation, spontaneous UM was recorded in the awake bitch. Effects of IV prostaglandin (PG) F2 alpha (5 micrograms/kg of body weight) and oxytocin (0.05 USP U/kg) and IM PGF2 alpha (25 micrograms/kg) were measured. Estradiol (1 to 25 micrograms/kg) was administered and the study was repeated 24 hours later. In awake bitches, spontaneous UM was 190% greater than UM in anesthetized bitches. Uterine motility was increased by more than 100% after IV PGF2 alpha or oxytocin and by 52% after IM PGF2 alpha. Estradiol abolished spontaneous UM, but did not affect drug-induced responses. Seemingly, spontaneous and drug-induced UM can be documented in the nonanesthetized bitch. 相似文献
56.
Joo Youn Oh † ‡ Mee Kum Kim † ‡ Hyun Ju Lee † ‡ Jung Hwa Ko † ‡ Won Ryang Wee † ‡ Jin Hak Lee † ‡ 《Veterinary ophthalmology》2009,12(S1):50-56
Objective Although variations exist between species with respect to outcomes after cryopreservation, little is known about the differences in the susceptibility of the corneal stroma to cryoinjury. We performed this study to investigate freeze–thaw-induced damage in keratocytes and collagen in rabbit, pig, and human corneas.
Animals studied Rabbit, pig, and human.
Procedures We prepared 250-μm-thick anterior stroma from rabbit, pig, and human corneas after scraping off the epithelium and endothelium. Each 250-μm-thick corneal stroma without epithelium was placed in a 50-mL tube, frozen with liquid N2 for 15 min and taken out to thaw rapidly at 37 °C. This procedure of rapid freezing and thawing was repeated three times. Differences between the species with respect to cells and collagen structures were examined using hematoxylin–eosin (H&E) staining, terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and transmission electron microscopy (TEM). We orthotopically transplanted the pig and rabbit corneal transplants after the triple freeze–thaw cycle into rabbit eyes and evaluated graft survival.
Results On gross examination, rabbit corneas became opaque after the triple freeze–thaw procedure, while pig and human corneas remained transparent. Histologically, keratocytes were apoptotic on TUNEL assay and TEM in rabbit, pig, and human corneas. Collagen fibrils were fragmented and the arrangement of collagen fibrils was severely disturbed in rabbit corneas on H&E staining and TEM; collagen was well preserved in pig and human corneas. Rabbit corneal stroma underwent autolysis after transplantation, whereas the pig corneal stroma remained clear for 1 month.
Conclusions Our study showed that rabbit corneal stroma was more susceptible to freeze–thaw injury than pig and human corneas. 相似文献
Animals studied Rabbit, pig, and human.
Procedures We prepared 250-μm-thick anterior stroma from rabbit, pig, and human corneas after scraping off the epithelium and endothelium. Each 250-μm-thick corneal stroma without epithelium was placed in a 50-mL tube, frozen with liquid N
Results On gross examination, rabbit corneas became opaque after the triple freeze–thaw procedure, while pig and human corneas remained transparent. Histologically, keratocytes were apoptotic on TUNEL assay and TEM in rabbit, pig, and human corneas. Collagen fibrils were fragmented and the arrangement of collagen fibrils was severely disturbed in rabbit corneas on H&E staining and TEM; collagen was well preserved in pig and human corneas. Rabbit corneal stroma underwent autolysis after transplantation, whereas the pig corneal stroma remained clear for 1 month.
Conclusions Our study showed that rabbit corneal stroma was more susceptible to freeze–thaw injury than pig and human corneas. 相似文献
57.
58.
Long‐term changes in recruitment of age‐0 Pacific bluefin tuna (Thunnus orientalis) and environmental conditions around Japan 下载免费PDF全文
Yukimasa Ishida Hiromu Fukuda Ko Fujioka Osamu Sakai Yuko Hiraoka Kazuhiro Oshima Shuya Nakatsuka Nobuaki Suzuki Hiroyuki Shimada 《Fisheries Oceanography》2018,27(1):41-48
Recruitment of age‐0 Pacific bluefin tuna (Thunnus orientalis) from 1952 to 2014 was examined by a sequential regime shift detection method. The regime shifts in recruitment were detected in 1957, 1972, 1980, 1994 and 2009. The durations of regime shift ranged from 8–15 years and averaged 13.0 years. In both the total (1952–2014) and data rich (1980–2014) periods, negative relationships were found between recruitment and the Pacific Decadal Oscillation in autumn, and positive relationships were found between recruitment and sea surface temperature (SST) anomalies in the northern part of the East China Sea, in the southwestern part of the Sea of Japan, and in the waters off Shikoku and Tokai in summer and autumn. The 1994 and 2009 regime shifts in recruitment occurred in the same years as shifts in SST anomalies in the northern part of the East China Sea in summer. These results suggest that the ocean conditions in the northern part of the East China Sea are closely related to recruitment of Pacific bluefin tuna, and that the warmer conditions result in higher recruitment of the species. 相似文献
59.
Takeuchi Y Matsuura S Fujino Y Nakajima M Takahashi M Nakashima K Sakai Y Uetsuka K Ohno K Nakayama H Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(10):1085-1089
Two cats showing chronic vomiting, diarrhea and weight loss were found to have leukocytosis with marked eosinophilia. Both cats were diagnosed with hypereosinophilic syndrome by the findings of increased eosinophils and their precursors in the bone marrow, eosinophilic infiltration into multiple organs, and exclusion of other causes for eosinophilia. Although cytoreductive chemotherapy with hydroxycarbamide and prednisolone was performed, these two cats died 48 days and 91 days after the initial presentation. 相似文献
60.
Mariusz Szymczak Edward Kołakowski Katarzyna Felisiak 《Journal Of Aquatic Food Product Technology》2013,22(6):566-581
This study investigated the effect of acetic acid concentrations from 3 to 8% on the physicochemical and sensory quality of marinated Atlantic and Baltic herring from fresh and frozen-thawed material. The increased concentration of acetic acid was found to exert a strong impact on decreased sensory scores, weight yield, and pH value as well as on an increased brightness parameter of meat. In turn, moisture, protein hydrolysis products (PHB), total volatile bases (TVB) content, and hardness parameter were affected by the higher addition of acid to a lesser extent. Enhanced protein hydrolysis was observed only at acetic acid concentration of 5% or 5–8%, whereas there was a decrease in the content of TVB only at an acid concentration of up to 4–5%. The marinated frozen-thawed fillets, compared to the fresh ones, required a greater addition of acid in the brine, by 1.5%, to reach a similar pH value. The freezing of fish contributed also to a decrease of PHB and free hydroxyproline, along with an increased concentration of acetic acid. The marinades from frozen-thawed herring contained more TVB, had worse color, and hardness parameters, as well as less yield. 相似文献