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131.
Both stem and crown mass affect tree resistance to uprooting 总被引:1,自引:0,他引:1
Tsutomu Urata Masato Shibuya Akio Koizumi Hiroyuki Torita JooYoung Cha 《Journal of Forest Research》2012,17(1):65-71
To examine the hypothesis that both stem and crown mass affect the resistance of a tree to uprooting and that tree resistance
increases with increasing crown mass, we conducted tree-pulling experiments on three Picea glehnii plantations (stands A, B, and C: 27–32 years old) that differed in tree density and slenderness ratio. Allometries between
crown and stem masses and between the critical uprooting moment and stem mass differed significantly among the three stands,
with the crown mass and critical moment significantly larger in stand C than in stands A or B, despite the same stem mass.
These results quantitatively verified our hypothesis. Allometries between crown and stem masses and between critical uprooting
moment and stem mass were highly significant in each stand but were stand specific. Therefore, these allometries can be used
to estimate tree resistance to uprooting in a given stand but not for data compiled from stands of various conditions and
tree shapes. The allometry between critical moment and aboveground mass did not differ among the three Picea stands; thus, it is not stand specific and is generally appropriate to use for estimating tree resistance. To increase tree
resistance to uprooting, we recommend light management for Picea glehnii plantations and probably other coniferous plantations as well. 相似文献
132.
Tsunehisa Miki Hiroyuki Sugimoto Keisuke Kojiro Yuzo Furuta Kozo Kanayama 《Journal of Wood Science》2012,58(4):300-308
The thermal properties and transitions of solid and ground wood samples conditioned at different humidity conditions were investigated by temperature-modulated differential scanning calorimetry. A time-dependent transition was detected as an endothermic peak in the total and non-reversing heat flows and as a step change in the reversing heat flow during the first heating run of samples with moisture contents above 5?%, but it disappeared in the second heating run. These different thermal behaviors indicate that the effect of heat and moisture on the thermal properties of wood is history dependent. This step change in the reversing heat flow is considered to be a glass transition of moist wood. Other relaxation processes (e.g., enthalpy relaxation) occur simultaneously with this glass transition. The temperature ranges of the transition and the relaxation decreased drastically as the moisture content increased up to 11?%, while they remained almost constant at higher moisture contents. In addition, the transitions of the ground wood occurred at lower temperatures than those of the solid wood at similar moisture contents. Kissinger plots revealed that the apparent activation energy for the glass transition of the solid wood with a moisture content of 11?% was about 600?kJ/mol, whereas that of the ground wood was 220?kJ/mol. 相似文献
133.
Michimasa Oguri Kanji Okano Hajime Ieki Masayuki Kitagawa Osamu Tadokoro Yoshinori Sano Kazato Oishi Hiroyuki Hirooka Hajime Kumagai 《Animal Science Journal》2013,84(9):650-655
Three types of bamboo pellets as a ruminant feed: P1 (ground bamboo (GB) cultured with the fungus Ceriporiopsis subvermispora (CGB) : soybean curd residue (T) : soy sauce cake (S) in a 5:4:1 ratio on a dry matter (DM) basis); P2 (GB : T : S = 5:4:1 on a DM basis); and P3 (CGB : T : S = 5.5:0.8:3.7 on a DM basis) were prepared. Four wethers were assigned in a 4 × 4 Latin square design experiment to evaluate the applicability of the bamboo pellets. The experimental treatments were C (control): fed alfalfa hay cubes (AC) only, and T1, T2 and T3: fed P1, P2, and P3 with AC by 1:1 on a DM basis, respectively. The digestibility of the DM, organic matter and acid detergent fiber of P1 were significantly higher than those of P2 and P3 (P < 0.05). The total digestible nutrient (TDN) contents of AC, P1, P2 and P3 were 56.5%, 60.2%, 53.2% and 47.0%, respectively. No significant differences in nitrogen retention or ruminal pH and NH3 were observed among the treatment groups. The results indicate that bamboo pellets cultured with C. subvermispora and mainly mixed with soybean curd residue improved nutritional quality of ground bamboo because of its high digestibility and TDN content. 相似文献
134.
Fumihito Takahashi Mariko Mochizuki Touko Sato Kinya Katayama Paul R. Kenyon Stephen T. Morris Peter D. Kemp Takeyuki Ozawa Fukiko Ueda Hiroyuki Tazaki 《Animal Science Journal》2013,84(6):496-501
The establishment of a classification system for domestic animals on consumed feed stuff is thought to be important from both a hygiene and market point of view. We collected plasma samples of Romney lambs (Ovis aries) which were fed one of the following: a herb‐clover mix (n = 10) which included chicory, red clover, white clover and plantain; a plant‐grass mix (n = 10) which included plantain, ryegrass and white clover; or a grass mix (n = 10) which included ryegrass and white clover. A total of 20 elements in plasma samples obtained from the lambs were analyzed using inductively coupled plasma mass spectrometry. The data were then analyzed by principal component analysis. The lambs were divided into three groups on a score plot depending on the different feed conditions. Furthermore, discriminant analyses of the elements were examined, using linear discriminant analysis with forward stepwise regression. This discriminant function correctly classified the samples from each group. The accuracy of classification of each group, as shown by 10‐fold cross‐validation, proved the effectiveness of the established discriminant function. It is concluded that using linear discriminant analysis might be a useful tool for the validation of elements from plasma in lambs grown in different conditions. 相似文献
135.
Kosei Ando Mayu Mizutani Yusuke Taniguchi Hiroyuki Yamamoto 《Journal of Wood Science》2013,59(4):290-298
To understand the viscoelasticity of wood three dimensionally, matched samples of Japanese cypress were loaded in uniaxial tensile creep in the longitudinal (L), radial (R), and tangential (T) directions at approximately 9.7 % equilibrium moisture content. Longitudinal and transverse strains were measured for the determination of viscoelastic Poisson’s ratios and three-dimensional viscoelastic compliance tensors concerning the normal strain. The changes in the transverse strains showed the same tendencies as those in the longitudinal strains, in all directions of loading. That is, during creep, the absolute value of transverse strain continued to increase with the gradual reduction in the increase rate; immediately after the removal of the load, it recovered rapidly, after which it continued to recover slowly. The transverse strain increased most easily in the T direction, followed by R and L, during creep. All the viscoelastic Poisson’s ratios and the absolute values of all elements of the viscoelastic compliance increased logarithmically with creep time. The three-dimensional viscoelastic compliance matrix for Japanese cypress is concluded to be asymmetric. 相似文献
136.
Glycosylated Porphyra-334 and Palythine-Threonine from the Terrestrial Cyanobacterium Nostoc commune
Ehsan Nazifi Naoki Wada Minami Yamaba Tomoya Asano Takumi Nishiuchi Seiichi Matsugo Toshio Sakamoto 《Marine drugs》2013,11(9):3124-3154
Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc commune (N. commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. commune. The glycosylation of porphyra-334 and palythine-threonine in N. commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments. 相似文献
137.
Fuminori TANIHARA Michiko NAKAI Hiroyuki KANEKO Junko NOGUCHI Takeshige OTOI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2013,59(4):385-392
In porcine oocytes, the function of the zona pellucida (ZP) with regard to sperm
penetration or prevention of polyspermy is not well understood. In the present study, we
investigated the effects of the ZP on sperm penetration during in vitro
fertilization (IVF). We collected in vitro-matured oocytes with a first
polar body (ZP+ oocytes). Some of them were freed from the ZP (ZP− oocytes) by two
treatments (pronase and mechanical pipetting), and the effects of these treatments on
sperm penetration parameters (sperm penetration rate and numbers of penetrated sperm per
oocyte) were evaluated. There was no evident difference in the parameters between the two
groups. Secondly, we compared the sperm penetration parameters of ZP+ and ZP− oocytes
using frozen-thawed epididymal spermatozoa from four boars. Sperm penetration into ZP+
oocytes was found to be accelerated relative to ZP− oocytes. Thirdly, we evaluated the
sperm penetration of ZP+ and ZP− oocytes at 1−10 h after IVF (3 h gamete co-incubation).
The proportions of oocytes penetrated by sperm increased significantly with time in both
groups; however, the number of penetrated sperm per oocyte did not increase in ZP−
oocytes. Finally, we performed IVF using ZP− oocytes divided into control (3 h) and
prolonged gamete co-incubation (5 h) groups. Greater numbers of sperm penetrated in the 5
h group than in the control group. These results suggest that the ZP and oolemma are not
competent factors for prevention of polyspermy in our present porcine IVF system. However,
it appears that ZP removal is one of the possibilities for reducing polyspermic
penetration in vitro in pigs. 相似文献
138.
Matsuura R Moriyama H Takeda N Yamamoto K Morita Y Shimamura T Ukeda H 《Journal of agricultural and food chemistry》2008,56(2):544-549
Sakura-cha (salted cherry blossom tea) is a Japanese tea that is traditionally served at celebrations such as wedding ceremonies. The production of Sakura-cha includes the immersion of cherry blossom flowers in Japanese plum vinegar, and through this process, the byproduct (plum vinegar extract of cherry blossom) is obtained. In this study, the antioxidant activity of the plum vinegar extract of cherry blossom was examined. The plum vinegar extract of cherry blossom had a greater superoxide anion scavenging activity compared with red wine, which is a well-known strong antioxidant. Liquid chromatography-mass spectrometry analysis showed that cyanidin-3-glucoside, cyanidin-3-rutinoside, and caffeic acid were the major components in the phenolic extract prepared from plum vinegar extract of cherry blossom, and they possessed superoxide anion scavenging activity. Caffeic acid is mainly responsible for the scavenging activity of phenolic extract; the contributions of cyanidin-3-glucoside and cyanidin-3-rutinoside were minor. 相似文献
139.
Ogawa K Sakakibara H Iwata R Ishii T Sato T Goda T Shimoi K Kumazawa S 《Journal of agricultural and food chemistry》2008,56(12):4457-4462
The anthocyanin composition and antioxidant activity of the crowberry ( Empetrum nigrum) were studied. High-performance liquid chromatography (HPLC) combined with a diode array detector and electrospray ionization mass spectrometry were used for identification and quantification of individual anthocyanins. Freeze-dried crowberry powder was extracted with 80% methanol containing 0.5% acetic acid and subjected to HPLC. Thirteen kinds of anthocyanins were identified. The major anthocyanins were cyanidin-3-galactoside and delphinidin-3-galactoside, at 8.04 and 8.62 mg/g extract, respectively. The HPLC profile of crowberry extract was similar to bilberry and blueberry. The total content of anthocyanins in crowberry was 41.8 mg/g extract, higher than the other nine major berry species (2.5-38.8 mg/g extract). The antioxidant activity was also evaluated using the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis(3-ethybenzothiazoline-6-sulfonic acid) radical quenching assays and the ferric reducing activity power assy. Crowberry extract exerted the strongest antioxidant activity. In conclusion, individual anthocyanins in crowberry were identified and then quantified in this study. Additionally, crowberry is suggested to be associated with a reduction in the risk of developing chronic diseases because of its strong antioxidant activity. 相似文献
140.
Noguchi J Ozawa M Nakai M Somfai T Kikuchi K Kaneko H Kunieda T 《The Journal of reproduction and development》2008,54(3):203-207
A gene for FK506 binding protein 6 (Fkbp6) expresses during a specific stage of male and female meiosis. Disruption of the gene influences male reproduction, i.e. arrests spermatogenesis, but not female reproduction. Using the mouse model (targeted disruption), the role of the gene in homologous chromosome pairing has been demonstrated in a previous study. For further understanding the function of Fkbp6 in chromosome synapsis, we evaluated chromosome pairings during male meiosis in the as/as rat, a spontaneous null mutation, and compared them with those of the mouse model. Electron microscopy of the pachytene nuclei unveiled several types of abnormal chromosome pairing in the rat model, as shown in the mouse previously. The frequencies of aberrant pairings in the knockout mice and mutant rats were 42 of 67 nuclei (62.7%) and 20 out of 74 nuclei (27.0%), respectively. In order to clarify the mechanism of male specific infertility in Fkbp6 deficiency, the localization of gammaH2AX, a marker protein of XY chromosome inactivation during male meiosis, was examined. Immunostaining of gammaH2AX unveiled normal localization of the molecule to XY chromosomes (XY body) in both models, showing the independency of FKBP6 in sex chromosome inactivation. Besides the XY body, focal localization of gammaH2AX was observed in accordance with the unsynapsed chromosomes in both types of null animal. These results indicate the fundamental role of Fkbp6 in homologous chromosome synapsis during male meiosis. In conclusion, male specific infertility under Fkbp6 deficiency remains unsolved. 相似文献