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141.
M. Tsutsumi Y. Takahashi S. Emoto N. Ito S. Sahara T. Yoshimura T. Watanabe 《Grass and Forage Science》2012,67(1):55-63
The accuracy of two simple methods was compared for the prediction of crude protein (CP) content of above‐ground plant material of mixed‐species composition on abandoned cultivated land in Japan. The first method is based on standard CP values (in g kg?1 dry matter) for individual species (STV method) as listed in the literature. The second procedure (GLM method) was an application of the generalized linear model using the relative above‐ground biomass of monocots and legumes, total herbage mass, and day of year. Predictions were made at the quadrat scale, and for surveyed sites based on average of values for five or six quadrats in a single survey. A ‘leave‐site‐out’ method was adopted for model validation of the generalized linear model. The observed values of CP content ranged between 21·5 and 161·9 g kg?1 dry matter (DM). With the STV method, the values of root mean square error (RMSE indicates average estimation error) were 50·9 at the quadrat level and 53·8 at the surveyed‐site level (both g kg?1 DM). When a ‘leave‐site‐out’ validation was carried out, the RMSE‐values for the GLM method were 23·2 at the quadrat level and 13·2 at the surveyed‐site level (both g kg?1 DM). We therefore propose adoption of the GLM method for the purpose of estimating the CP content in herbage on abandoned sites. 相似文献
142.
143.
Kohei Osaki Shozo Fujiyama Akiko Nakayama Yoshiaki Shimizu Shin-ichi Ito Shuhei Tanaka 《Journal of General Plant Pathology》2008,74(4):281-288
The relation between diversity of pathogenicity on clubroot-resistant (CR) cultivars of Chinese cabbage (Brassica rapa subsp. pekinensis) bred in Japan and DNA polymorphisms in 17 populations of Plasmodiophora brassicae from cruciferous plants was examined by inoculation tests and random amplified polymorphic DNA (RAPD) analysis using 18 arbitrary
primers. Four pathotypes (A–D) were identified after inoculation of six CR cultivars of Chinese cabbage in the 17 populations
from cruciferous crops. A relatively high level of genetic diversity was also detected among these populations in the RAPD
analysis. Although the four pathotypes could not be clearly differentiated using the RAPD data, most populations of three
pathotypes had a consistent location on the dendrogram. All pathotype B (virulent on five cultivars except Utage 70) and D
(avirulent on all cultivars) populations, which were common in incompatible interactions with cv. Utage 70, were located in
a single subcluster. All five pathotype C populations (virulent only on cv. Utage 70) except for one population grouped in
another single subcluster. Because four pathotype A populations (virulent on all six cultivars, races 4 and 9) fell in different
subclusters, the populations may be genetically polyphyletic. Populations from cruciferous weed Cardamine flexuosa differed remarkably from those from cruciferous crops in pathogenicity on common cultivars of Chinese cabbage and turnip
and C. flexuosa, but they grouped in a single cluster with all race 9 populations from crops. Race 9 populations from crops may thus be closely
related to populations from the weed rather than to races 1 and 4 from crops. 相似文献
144.
Masaru Fujinoki Tomoko Koito Suguru Nemoto Mitsugu Kitada Yoko Yamaguchi Susumu Hyodo Hideki Numanami Nobuyuki Miyazaki Koji Inoue 《Fisheries Science》2012,78(1):139-146
Various invertebrates inhabiting hydrothermal vents harbor thiotrophic endosymbionts that provide the host with nutrients
and are possibly involved in the detoxification of harmful sulfides. In this study, we first determined the partial 16S rRNA
gene sequence of the thiotrophic symbiont of the deep-sea mussel Bathymodiolus septemdierum, a dominant species at hydrothermal vents in the Izu–Ogasawara (Bonin) area. We then designed a new probe, Bsob692, for fluorescent in situ hybridization (FISH) using regions completely conserved among thiotrophic symbionts of all
bathymodiolin mussels and established the protocol for FISH to compare the distribution and amount of the symbiont using an
image analysis program that is commercially available. We compared fluorescent intensity in the gill of the mussels collected
at different sites and found a higher intensity in specimens collected from a site with higher sulfide concentration. We also
compared mussels reared in the presence and absence of sulfide and found that the former had a higher fluorescent intensity. 相似文献
145.
146.
Shuichi Ito Makiko Hirose Mari Iwahara Azusa Yatsushiro Atsushi Matsumoto Masayuki Tanaka Chinobu Okamoto Ken‐ichi Yayou Tsuyoshi Shimmura 《Animal Science Journal》2017,88(4):691-695
The rhythmic locomotor behavior of flies and mice provides a phenotype for the identification of clock genes, and the underlying molecular mechanism is well studied. However, interestingly, when examining locomotor rhythm in the wild, several key laboratory‐based assumptions on circadian behavior are not supported in natural conditions. The rooster crowing ‘cock‐a‐doodle‐doo’ is a symbol of the break of dawn in many countries. Previously, we used domestic inbred roosters and showed that the timing of roosters' crowing is regulated by the circadian clock under laboratory conditions. However, it is still unknown whether the regulation of crowing by circadian clock is observed under natural conditions. Therefore, here we used red jungle fowls and first confirmed that similar crowing rhythms with domesticated chickens are observed in red jungle fowls under the laboratory conditions. Red jungle fowls show predawn crowing before light onset under 12:12 light : dim light conditions and the free‐running rhythm of crowing under total dim light conditions. We next examined the crowing rhythms under semi‐wild conditions. Although the crowing of red jungle fowls changed seasonally under semi‐wild conditions, predawn crowing was observed before sunrise in all seasons. This evidence suggests that seasonally changed crowing of red jungle fowls is under the control of a circadian clock. 相似文献
147.
Kazumasu Sasaki Tatsushi Mutoh Tomoko Mutoh Ryuta Kawashima Hirokazu Tsubone 《Veterinary anaesthesia and analgesia》2017,44(1):7-16
Objective
To compare electrical velocimetry (EV) noninvasive measures of cardiac output (CO) and stroke volume variation (SVV) in dogs undergoing cardiovascular surgery with those obtained with the conventional thermodilution technique using a pulmonary artery catheter.Study design
Prospective experimental trial.Animals
Seven adult Beagle dogs with a median weight of 13.6 kg.Methods
Simultaneous, coupled cardiac index (CI; CO indexed to body surface area) measurements by EV (CIEV) and the reference pulmonary artery catheter thermodilution method (CIPAC) were obtained in seven sevoflurane-anaesthetized, mechanically ventilated dogs undergoing experimental open-chest cardiovascular surgery for isolated right ventricular failure. Relationships between SVV or central venous pressure (CVP) and stroke volume (SV) were analysed to estimate fluid responsiveness. Haemodynamic data were recorded intraoperatively and before and after fluid challenge.Results
Bland–Altman analysis of 332 matched sets of CI data revealed an overall bias and precision of – 0.22 ± 0.52 L minute?1 m?2 for CIEV and CIPAC (percentage error: 30.4%). Trend analysis showed a concordance of 88% for CIEV. SVV showed a significant positive correlation (r2 = 0.442, p < 0.0001) with SV changes to a volume loading of 200 mL, but CVP did not (r2 = 0.0002, p = 0.94). Better prediction of SV responsiveness (rise of SV index of ≥ 10%) was observed for SVV (0.74 ± 0.09; p = 0.014) with a significant area under the receiver operating characteristic curve in comparison with CVP (0.53 ± 0.98; p = 0.78), with a cut-off value of 14.5% (60% specificity and 83% sensitivity).Conclusions and clinical relevance
In dogs undergoing cardiovascular surgery, EV provided accurate CO measurements compared with CIPAC, although its trending ability was poor. Further, SVV by EV, but not CVP, reliably predicted fluid responsiveness during mechanical ventilation in dogs. 相似文献148.
Fatma F. Abdel-Motaal Soad A. El-zayat Yuki Kosaka Magdi A. El-Sayed Rumi Kashima Yukie Maeda Mortada S. M. Nassar Shin-ichi Ito 《Journal of General Plant Pathology》2010,76(2):102-111
The antifungal activities of hyoscyamine and scopolamine, major alkaloids extracted from the desert plant Hyoscyamus muticus, against two rice pathogens, Magnaporthe oryzae and Rhizoctonia solani, were studied. The minimum inhibitory concentration of hyoscyamine that resulted in distinctive inhibition (MIC50) was 1 μg/ml for both fungi. Exposure to hyoscyamine caused the leakage of electrolytes from the mycelia of both fungi. Hyoscyamine
(>1 μg/ml) irreversibly delayed or inhibited conidial germination and appressorium formation in M. oryzae grown on polystyrene plates. Hyoscyamine effectively inhibited the attachment of conidia to the surface of rice (Oryza sativa) leaves and inhibited appressorium formation on the leaves. A high concentration of scopolamine (1000 μg/ml) also delayed
or inhibited conidial germination in M. oryzae, but conidial germination was restored after washing the conidia with water. Antifungal activity of hyoscyamine was reduced
by scopolamine. Magnaporthe oryzae infection was significantly suppressed (by >95%) in leaves of intact rice plants treated with hyoscyamine (10 μg/ml). Moreover,
10 μg hyoscyamine/ml significantly reduced the disease severity index for sheath blight to ≤0.2, when compared with the disease
index of control plants (>7.0). Hyoscyamine (>20 μg/ml) completely inhibited sclerotial germination and development of R. solani by delaying the initiation, maturation, and melanization of the sclerotia. These results suggest that tropane alkaloids may
be useful for controlling blast and sheath blight diseases of rice and for studying the mechanisms that regulate conidial
germination in M. oryzae and sclerotial germination and development in R. solani. 相似文献
149.
Fatma F. Abdel-Motaal Magdi A. El-Sayed Soad A. El-Zayat Mortada S. M. Nassar Shin-ichi Ito 《Journal of General Plant Pathology》2010,76(5):358-361
Floral rot of Egyptian henbane (Hyoscyamus muticus L.) was found on potted plants in a greenhouse in Yamaguchi city, Japan, in the late summer of 2008 and 2009. The symptoms
were identical to those of rots caused by Choanephora species. The pathogen was isolated and identified as C. cucurbitarum (Berkeley and Ravenel) Thaxter. This new disease was named Choanephora rot (Kougai-kabi-byo) of Egyptian henbane. 相似文献
150.
Yoshio Kijidani Tetsuya Hamazuna Satoshi Ito Ryushi Kitahara Shinsuke Fukuchi Nobuya Mizoue Shigejiro Yoshida 《Journal of Wood Science》2010,56(1):1-6
The lumber from sugi plantations in Japan displays large intra- and intertree variation in mechanical properties, even within
a stand. These variations seem to be induced by the effects of the characteristics of cultivars as well as the effects of
growth traits on mechanical properties. Therefore, the effects of growth traits on mechanical properties per cultivar need
to be precisely examined. In this study, we focused on the effects of growth traits, especially height-to-diameter ratio (H/D
ratio), on stem stiffness per cultivar. Sixteen cultivars were classified into three groups according to the relationships
between stem stiffness and growth traits. In cultivars that showed a close correlation between growth traits and stem stiffness,
it was assumed that stem stiffness could be controlled to a certain extent by silvicultural practices using the H/D ratio
as an indicator. In cultivars that showed a weak correlation between growth traits and stem stiffness, selecting cultivars
for the production of logs with higher mechanical properties seemed to be effective; in this study, Kumotoshi, Tanoaka, and
Edanaga were found to be suitable. Tree age and site index may be important factors for producing wood with higher mechanical
properties. 相似文献