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41.
Kiriko Nakamura Kiyoshi Matsubara Hitoshi Watanabe Hisashi Kokubun Yoshihiro Ueda Naomi Oyama-Okubo Masayoshi Nakayama Toshio Ando 《Scientia Horticulturae》2006
In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed. 相似文献
42.
43.
Seiichi Kanetani Mitsuteru Akiba Katsunori Nakamura Koichiro Gyokusen Akira Saito 《Journal of Forest Research》2001,6(4):307-310
The process of decline of an endangered tree species,Pinus armandii var.amamiana, was monitored on the southern slope of Mt. Hasa-dake in Yaku-shima Island from 1994 to 1998. There are 163 trees ofP. armandii var.amamiana over 1.3 m in height. They are distributed on steep ridges and rocks with a thin soil layer mostly consisting of friable
granite. During the monitoring period, 21 trees ofP. armandii var.amamiana died and the mortality rate was 12.9%. Dead trees were categorized into three types: standing, uprooted and landslide. The
uprooted- and landslide-typed dead trees were found only after a severe typhoon struck Yaku-shima Island. This suggests that
the combination of fragile site conditions and severe typhoons play an important role in the process of decline ofP. armandii var.amamiana. The standing-typed dead trees were presumed to have been killed by pine wilt disease, accounting for 71.4% of the dead trees.
However,Bursaphelenchus xylophilus, the cause of pine wilt disease, was not detected from any of the wood chips or branch samples from the standing-typed dead
trees ofP. armandii var.amamiana. This might indicate that some factor(s) other than pine wilt disease could be responsible for the standing-typed death ofP. armandii var.amamiana in natural habitats.
A part of this paper was presented at the 109th Meeting of the Japanese Forestry Society. 相似文献
44.
Chikaya Sakai Atok Subiakto Hani Sitti Nuroniah Naoto Kamata Koji Nakamura 《Journal of Forest Research》2002,7(2):73-80
We developed a vegetative propagation system for mass-producing three dipterocarps species,Shorea selanica Bl.,Shorea leprosula Mig., andShorea platyclados Sloot. This system uses fog evaporative cooling inside a greenhouse to reduce the leaf-to-air vapor pressure deficit (leaf-to-air
VPD) inside the propagator, even under high irradiance conditions. This cooling method has no negative influence on medium
conditions such as overwetting. A plastic tent propagator combined with this cooling method was used for vegetative propagation
experiments. In mass-production experiments, the annual rooting percentages from the cuttings were low in the first 2 years
(1997–1998) due to operational problems of the tent propagator (S. selanica, 48–51%;S. leprosula, 56–59%;S. platyclados: 50–63%). A hard cover propagator improved the rooting percentages in the mass-production experiments in 1999 because it
made operations easier (S. selanica, 70%;S. leprosula, 77%;S. platyclados, 77%). This system, which uses a combination of fog evaporative cooling and a hard plastic propagator, should be useful for
the mass propagation of these dipterocarp planting stocks.
This study was carried out under a joint project of the Ministry of Forestry, Indonesia and Komatsu Ltd. The project was supported
by Research Association for Reforestation of Tropical Forest (RETROF) organized by Japanese Forestry Agency. 相似文献
45.
Riparian forests greatly influence aquatic ecosystems by providing shade cover, which controls water temperature and limits
primary production. We examined the relationship between forest cover and summer stream temperature in northernmost Japan.
Heat budget and statistical analyses were employed and the results were compared. Heat budget analysis revealed that the water
temperature would decrease almost linearly from 29°C to 25°C with an increase in forested reaches along a 3.2 km stretch of
the river. Multiple regression analysis by the stepwise method chose only open channel length as a variable to explain the
variation in maximum stream temperature. A sharp increase in stream temperature was noted when riparian forest cover was removed
in short lengths, of up to 1.0km; this increasing trend gradually flattened as the length of open stretch increased. Thus,
even small openings in the riparian canopy resulted in drastic rises in summer stream temperature. The maximum summer temperatures
estimated by the two methods were coincided, and can therefore be accurately estimated by regression analysis. Retrospective
analysis based on the regression equation showed that the maximum summer temperature in 1947 was 6°C lower than at present,
and that a sharp increase occurred from 1947 to 1960, a period of rapid expansion of agricultural land development in the
watershed. 相似文献
46.
Amin Setyo Leksono Kenta Takada Nobukazu Nakagoshi Koji Nakamura 《Journal of Forest Research》2006,11(1):61-64
A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness,
and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness
were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results
showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for
Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct
species compositions in both families among layers. 相似文献
47.
Yasuyuki Tachiki Tetsuhiko Yoshimura Hisashi Hasegawa Tomonori Mita Tetsuro Sakai Futoshi Nakamura 《Journal of Forest Research》2005,10(6):419-427
The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest
canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro
XR and GPSMAP 76S, which are categorized as “high-end mapping” and “general navigation” GPS receivers, respectively. The field
tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better
multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand
density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline
simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant
factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential
GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning
mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation
was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm,
especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because
its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver. 相似文献
48.
Surgical correction of gastro‐oesophageal intussusception with bilateral incisional gastropexy in three dogs
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Three dogs presented for evaluation of acute onset tachypnoea and dyspnoea following episodes of vomiting and/or regurgitation. Thoracic radiographs were suggestive of a gastro‐oesophageal intussusception in all three dogs; one dog also showed evidence of aspiration pneumonia. All three dogs underwent surgical correction with a bilateral incisional gastropexy. All dogs recovered from anaesthesia uneventfully and were discharged from the hospital 3 days after presentation. Persistent megaoesophagus was evident in all three dogs, and they are being chronically managed with a strict feeding regime and pro‐motility agents. 相似文献
49.
Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease
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T. Osuga K. Nakamura T. Morita S.Y. Lim K. Nisa N. Yokoyama N. Sasaki K. Morishita H. Ohta M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1518-1523
Background
In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.Objectives
To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.Animals
Forty‐three client‐owned dogs with CVHD.Methods
In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.Results
Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.Conclusions and Clinical Importance
These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD. 相似文献50.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers
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Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献