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101.
A new prenylated flavonol, papyriflavonol A, was isolated from the root barks of Broussonetia papyrifera. The structure of this compound was elucidated as 5,7,3',4'-tetrahydroxy-6,5'-di-(gamma,gamma-dimethylallyl)-flavonol (1) by spectroscopic analysis. 相似文献
102.
The internal transcribed spacer (ITS) regions of rDNA and the intervening 5.8S rRNA gene for the powdery mildew fungi Erysiphe (sect. Microsphaera) pulchra and Phyllactinia guttata were amplified using standard polymerase chain reaction (PCR) protocols and the universal primer pairs, ITS1 and ITS4. PCR products for ITS were analysed by electrophoresis in a 1.5% agarose gel and sequenced. The size of the amplified ITS products (approximately 650 bp) were not sufficiently different to allow reliable differentiation of E. pulchra and P. guttata; however, their sequences were distinct. Specific primers for E. pulchra and P. guttata were developed and evaluated for use as diagnostic tools. The diagnostic band size from E. pulchra‐specific primer pair was 568 bp while the P. guttata band was 597 bp; the two primer pairs were highly specific to E. pulchra and P. guttata. Comparison of ITS sequences with information in the GenBank showed a very close similarity between sequences of E. pulchra isolates from Cornus florida in the USA and isolates collected on Cornus kousa in Japan. BLAST analysis of the sequence of the 650‐bp band from P. guttata revealed a close alignment with sequences of P. moricola (92%), P. kakicola (94%), and P. fraxini (92%). The sequence of P. guttata in C. florida also had a 98% identity with P. guttata in Calycanthus occidentalis and 94% identity with P. guttata in Corylus cornuta. 相似文献
103.
V. Geissen R. -Y. Kim A. Schning St. Schütte G. W. Brümmer 《Forest Ecology and Management》2003,180(1-3):75-83
We investigated the initial effects of strip wise soil loosening (0–35 cm depth) on soil chemical and physical parameters by using a deeply working rotary cultivator in combination with liming and mixing of the dolomite with the soil material of acidic forests. The investigations took place 8 months after the treatment. pH values and contents of exchangeable Ca and Mg increased significantly at the tilled depth whereas the content of exchangeable Al and easily soluble P decreased. The rate of mineralisation increased at this depth which was shown by a loss of Corg, Ntot and short-term loss of NO3-N. The treatment led to a mobilisation of Mn at the tilled depth. However, the content of exchangeable Pb decreased due to an increased pH value. Below the tillage depth of 35 cm only partly significant changes of exchangeable Mn and NO3-N were found. The total porosity and bulk density at 10–15 and 40–45 cm depths were not significantly different from those in the control plot, but the rate of infiltration increased significantly. 相似文献
104.
A half-scale model of a light-frame shear wall was developed to evaluate the racking performance of a fullscale shear wall (prototype). The effect of nail size on the performance of the shear wall was also investigated using models constructed with three types of nail. Materials for the model were determined through experimental methods, which included nail-head push-through, stud-to-sheathing nail connection, and static bending tests. Materials with which the model was made to be in similarity to the prototype were three-layer 4.8-mm plywood, 39.72-mm long nails, and 1 × 2 lumber cut from 2 × 4 studs. In accordance with ASTM E 72 and ASTM E 564, racking resistance tests were conducted on 20 shear walls. The results showed that the maximum load capacities of the prototype walls could be evaluated by the model without significantly different failure modes. Tests on the effect of nail size revealed that increasing the nail head diameter may improve the performance of shear walls.Parts of this paper were presented at the International Conference on Effective Utilization of Plantation Timber (ICEUPT'99), Chi-Tou, Taiwan, May 1999; and the World Conference on Timber Engineering (WCTE2000), Whistler, Canada, July–August 2000 相似文献
105.
Previous investigations have suggested waxy (amylose‐free) wheats (Triticum aestivum L.) possess weak gluten properties and may not be suitable for commercial gluten extraction. This limitation could prevent the use of waxy wheat as a source of unique starch, because gluten is a by‐product of the wheat starch purification process. Fifty waxy wheat lines were used to determine the extent to which gluten protein and other grain quality related traits might vary and, consequently, allow the development of waxy wheat with acceptable gluten properties. Among the waxy lines, significant variation was observed for all measured quality traits with the exception of flour protein concentration. No waxy entries statistically equaled the highest ranking nonwaxy entry for grain volume weight, falling number, flour yield, or mixograph mix time. No waxy lines numerically exceeded or equaled the mean of the nonwaxy controls for falling number, flour yield, or mixograph mix time. For grain and flour protein related variables, however, many waxy lines were identified well within the range of acceptability, relative to the nonwaxy controls used in this study. Approximately 50% of the waxy lines did not differ from the highest ranking nonwaxy cultivar for grain and flour protein concentrations. Forty‐three (86%) of the tested waxy lines were not sig‐nificantly different from the nonwaxy line with the highest mixograph mixing tolerance, 22/50 (44%) of the waxy wheat lines did not differ from the highest ranking nonwaxy line in gluten index scores, and 17/50 (34%) did not differ from the highest ranking nonwaxy line in extracted wet gluten. All waxy experimental lines produced gluten via Glutomatic washing. The quality of the gluten, as measured both by mixograph and gluten index, varied widely among the waxy lines tested. These observations suggest that weak gluten is not a natural consequence of the waxy trait, and waxy cultivars with acceptable gluten properties can be developed. 相似文献
106.
A study was established in the Missouri Ozarks to evaluate coppice regeneration of oak. Five years after a 32-year-old stand was clearcut and regenerated naturally through stump sprouts, the dominant sprout on each stump was identified based upon height. Treated plots were thinned to the single dominant sprout on each stump whereas control plots were not thinned. Twenty-five years later the largest 247, 371, 494, and 618 stems per ha were examined and height of the dominant sprout at age 5 was found to be strongly related to dbh at age 30 in both thinned and unthinned plots. However, in the thinned plots, the largest 494 stems per ha were on average 11%, 28%, and 58% greater, respectively, in height, dbh, and volume compared to similar dominant sprouts in unthinned plots. Logistic regression analysis was used to develop curves for the evaluation of potential gains from clump thinning. In this analysis, the average height of a stand at age 5 was used to estimate thinning gains at age 30. 相似文献
107.
This study established a prediction model for bending properties of glued-laminated timber (glulam) using optimized knot and
modulus of elasticity (MOE) distributions of lumber laminate as the main input variables. For this purpose, knot and MOE data
were investigated for all pieces of lumber that were prepared for glulam manufacturing, and statistical distributions of knot
size, knot number in one lumber, and MOE of each laminate were optimized as distribution functions. These knot and MOE data
were used as input variables in the prediction model for bending properties, and were also used in generating virtual glulam
using the inverse transform method. Prediction of bending properties for glulam was carried out using the transformed section
method, which is partially provided in ASTM D 3737 (Annex A4). Predicted values were compared with those from full-scale four-point
bending tests for 60 six-layered glulams with 10 different laminar combinations. Finally, the allowable bending properties
of glulam for each specific laminate combination were determined by calculating the fifth percentile of the modulus of rupture
and the average modulus of elasticity from virtual test results of more than 1000 virtual glulams. From the results of this
study, predicted bending properties for glulam and their distributions could be used for structural design in both allowable
stress design and limit state design. 相似文献
108.
STRAIN ELASTOGRAPHY USING DOBUTAMINE‐INDUCED CAROTID ARTERY PULSATION IN CANINE THYROID GLAND 下载免费PDF全文
Gahyun Lee Sunghoon Jeon Sang‐Kwon Lee Hyunwoo Kim Dohyeon Yu Jihye Choi 《Veterinary radiology & ultrasound》2015,56(5):549-553
Thyroid disease is common in dogs and conventional ultrasonography is a standard diagnostic test for diagnosis and treatment planning. Strain elastography can provide additional information about tissue stiffness noninvasively after applying external or internal compression. However, natural carotid artery pulsations in the canine thyroid gland are too weak to maintain sufficient internal compression force. The objective of the present study was to describe the feasibility of strain elastography for evaluating the canine thyroid gland and the repeatability of dobutamine‐induced carotid artery pulsation as an internal compression method. In seven healthy Beagle dogs, strain on each thyroid lobe was induced by external compression using the ultrasound probe and internal compression using carotid artery pulsation after dobutamine infusion. The thyroid appeared homogeneously green and the subcutaneous fat superficial to the thyroid lobe appeared blue. Strain values and strain ratios did not differ among dogs or between the left and right lobes. Interobserver repeatability was excellent for both compression methods. Intraobserver repeatability of the strain ratio measured using the carotid artery pulsation method (intraclass coefficient correlation = 0.933) was higher than that measured using the external compression method (0.760). Mean strain values of thyroid lobes for the external compression method (142.93 ± 6.67) differed from the internal method (147.31 ± 8.24; P < 0.05). Strain ratios between the two methods did not differ. Strain elastography was feasible for estimating thyroid stiffness in dogs. Carotid artery pulsation induced by dobutamine infusion can be used for canine thyroid strain elastography with excellent repeatability. 相似文献
109.
110.
Young-Don Son Da-Jung Kim Ji-Houn Kang Dong-Woo Chang Young-Bae Jin Dong-In Jung Chulhyun Lee Mhan-Pyo Yang Sang-Rae Lee Byeong-Teck Kang 《Irish veterinary journal》2015,68(1)
A 16-year-old, castrated, male English cocker spaniel dog was presented due to generalized alopecia. Routine clinical pathology, endocrine and abdominal ultrasonography results were consistent with a diagnosis of pituitary-dependent hyperadrenocorticism. The adenohypophyseal lesion was clearly visualized on both 3 T and 7 T magnetic resonance imaging (MRI) of the pituitary gland. Although biochemical and MRI findings were consistent with a functional pituitary microtumor, a pituitary lesion was not detected using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). This report firstly describes the application of high-resolution FDG-PET to a spontaneous pituitary microtumor in a dog. 相似文献