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71.
The height-reducing gene Rht8 was introduced into Italian wheats by breeder Nazareno Strampelli from the Japanese landrace Akakomugi, and has been widely
used in wheats adapted to southern and eastern European conditions. Following identification of a close linkage to Rht8, microsatellite marker Gwm261 has been used extensively to screen large numbers of diverse international germplasm. A 192bp allele at this locus has been
taken as “diagnostic” for Rht8 and used to infer the international distribution of Rht8. In this paper, we report several instances of cultivars and mapping populations that vary for the presence of the 192bp
allele at the Xgwm261 locus (Xgwm261
192
), but with no associated reduction in height, suggesting a lack of association with Rht8. For instance, in the population derived from a cross between Sunco (Rht-B1b, Xgwm261
165
) and Tasman (Rht-D1b, Xgwm261
192
), there were significant height differences associated with the segregation of Rht-B1b and Rht-D1b, but no height differences between Xgwm261 genotypes. Similar results were obtained in a population derived from the cross between Molineux (Rht-B1b, Xgwm261
192
) and Trident (Rht-D1b Xgwm261
208
). In contrast, the cross between Trident and Chuanmai 18 (Xgwm261
192
) gave significant height effects at both the Rht-D1 and Xgwm261 loci, with no epistatic interaction between loci. Chuanmai 18 is closely related to the Strampelli wheat Mara (ancestrally
derived from Akakomugi) and is therefore likely to carry Rht8. The old Japanese cultivar Norin 10, used by Norman Borlaug to introduce Rht-B1b and Rht-D1b into Mexican wheats, also has a 192bp allele at the Xgwm261 locus, and the sequence of the amplified product is identical to that of Akakomugi. We suggest that the widespread use of
Norin 10-derived germplasm during and after the Green Revolution introduced a second haplotype into international germplasm,
in which Xgwm261
192
has no association with Rht8. Therefore, the presence of Xgwm261
192
is only indicative of Rht8 in wheat cultivars that have inherited this allele from Akakomugi or a Strampelli wheat ancestor. 相似文献
72.
Lifang Liu Qianli Wang Longdi Cheng Jingfang Qian Jianyong Yu 《Fibers and Polymers》2011,12(1):95-103
Natural bamboo fibers have excellent properties suggesting that there is a good potential for them to be used in textiles;
however, they have not received the attention that they deserve owing to their coarse and stiff quality. Therefore, a chemical
method for extraction and modification of natural bamboo fibers for textile end uses were developed and optimized in this
paper. The quality of natural bamboo fibers were characterized by their chemical composition, linear density, and tenacity.
Experimental results show that the modified bamboo fibers are finer, with significant lower content of noncellulosic substances.
The processing parameters are optimized as: 20 g/l NaOH, 3 g/l Na5P3O10, 5 g/l Na2SO3, 3 g/l penetrating agent, with a fiber to liquid ratio of 1:10, at 100 °C for 2 h, and the bamboo fiber thus produced has cellulose
amount of 73.25 %, fineness of 3.26 tex, average length of 44.5 mm, breaking elongation of 2.8 % and tenacity of 2.41 cN/dtex.
The result of this study may offer a possibility of developing natural bamboo fibers into practical applications in textiles. 相似文献
73.
This study analyzes how the silhouette of virtual garments applied to virtual avatars is altered according to various virtual
fabric properties. This study measures the properties of real fabrics that include a charmeuse (#F1) and gabardine (#F2) using
the Fabric Analysis by Simple Testing system; in addition, the material properties of different real fabrics were applied
to that of the virtual fabric. It then evaluates the drape stiffness and silhouette of the virtual garments according to the
different fabrics. This study also compared the virtual garment silhouette of sample fabric #F1-S that changed only the stretch
property of the sample fabric #F1 with the virtual garment silhouette of sample fabric #F1. The results show that the fabric
properties including bend, thickness, weight, stretch, shear values affect the drape stiffness, silhouette, and fit of the
virtual garment simulated on virtual avatars and may be used for the realistic virtual garment technology. 相似文献
74.
This study developed a novel PHB-lignin-jute biodegradable composite with preferable mechanical properties and low water absorption.
The appearances of fracture surface of composites were analyzed by scanning electron microscope. The result suggested a Gaussian-like
distribution of the size particles supporting the presence of lignin with a radius smaller than 0.5 μm. According to X-ray
diffraction, the presence of lignin and jute fibers was decreased the crystallization of PHB. Moreover, the glass transition
temperature of PHB increased, and the endotherm during glass transition was decreased. The maximum tensile strength and modulus
of composites were obtained with 30 wt% jute fiber contents and 4 wt% lignin contents. The presence of jute fibers was largely
increased the water absorption of composites. However, the presence of lignin was effectively decreased the water absorption
of composites at saturation levels. 相似文献
75.
Krzysztof Dziedzic Danuta Górecka Artur Szwengiel Hanna Sulewska Ivan Kreft Elżbieta Gujska Jarosław Walkowiak 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(1):82-88
In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP–UHPLC–ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum. 相似文献
76.
Luciana Linhares de Azevedo Bittencourt Kelly Alencar Silva Valéria Pereira de Sousa Gizele Cardoso Fontes-Sant’Ana Maria Helena Rocha-Leão 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(4):278-286
In the processing of fruits such as blueberry (Vaccinium sp), that has high levels of phenolic acid, the food industry produces tons of organic waste that causes harm to the environment. Encapsulation is a technique used to take advantage of these wastes. Several methods are used to encapsulate substances, among them ionotropic gelation proves to be a simple, precise, efficient and economical method for obtaining particles with encapsulated bioactives. In this manner, the aim of this study was to test sodium alginate as wall material to encapsulate blueberry residue by ionotropic gelation. The microbeads were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), total phenolic compounds, antioxidant capacity and in vitro dissolution. The results showed that the microbeads had surface invagination; retention of 67.01% of the phenolic compounds after encapsulation and 68.2%, phenolic release 120 min after in vitro dissolution. The results suggest that the tested matrix was suitable for encapsulation. The produced microbeads are promising for applications in food products, once the phenolic compounds present in the blueberry residues were maintained after encapsulation. 相似文献
77.
Heon Woong Kim Sung Ryong Kim Young Min Lee Hwan Hee Jang Jung Bong Kim 《Potato Research》2018,61(1):1-17
Anthocyanin concentration and composition and the effect of steaming and baking on these were evaluated in tubers of Korean red- and purple-fleshed potato cultivars and breeding clones using liquid chromatography with diode array detection and electrospray ionization-mass spectrometry (LC-DAD-ESI-MS). Twenty-six anthocyanins were isolated, of which 24 were identified. Remarkably, five cis isomers were identified, of which four, viz., cis-petanin, cis-peonanin, petunidin 3-cis-caffeoylrutinoside-5-glucoside, and petunidin 3-cis-feruloylrutinoside-5-glucoside, are reported for the first time. Moreover, pelargonidin 3-p-coumaroylrutinoside-5-glucoside (pelanin), peonidin 3-p-coumaroylrutinoside-5-glucoside (peonanin) and petunidin 3-p-coumaroylrutinoside-5-glucoside (petanin) were identified as the principal anthocyanins. We found that the total anthocyanin content of coloured potatoes was decreased by steaming and baking compared with the raw state. In addition, we performed partial least square discriminant analysis (PLS-DA) to discriminate between the analyzed anthocyanins. Cis isomers seemed to play a vital role as a biomarker in the PLS-DA model based on the type of processing and colour of the tubers. 相似文献
78.
Proyuth Ly Quynh Duong Vu Lars Stoumann Jensen Arjun Pandey Andreas de Neergaard 《Paddy and Water Environment》2015,13(4):465-475
We studied the effects of water regimes and nutrient amendments on CH4 and N2O emissions in a 2 × 3 factorial, completely randomised growth chamber experiment. Treatments included continuously flooded (CF) and alternate wetting and drying (AWD), and three organic amendments: no amendment-control, rice straw (RS) and biochar (BC). Compound fertiliser was applied to all treatments. Rice was grown in columns packed with a paddy soil from Cambodia. Results revealed faster mineralisation of organic carbon (RS and BC) when applied in water-saturated conditions lasting for 2 weeks instead of flooding. This resulted in lower total CH4 emissions in treatments under AWD than those under the CF water regime, namely 44 % in RS treatments and 29 % in BC treatments. Nitrous oxide fluxes were generally non-detectable during the experimental period except after fertilisation events, and the total N2O–N emissions accounted for on average 1.7 % of the total applied mineral fertiliser N. Overall, the global warming potentials (GWPs) were lower in treatments under AWD than those under the CF water regime except for the control treatment with only mineral fertiliser application. Grain yields were slightly higher in treatments under AWD than the CF water regime. Hence, the yield-scaled GWP was also lower in the treatments under the AWD water regime, namely 51 % in RS, 59 % in BC and 17 % in control treatments. Control treatments had the lowest GWP, but provided the highest yield. The yield-scaled GWP under these treatments was therefore lower than under the other treatments. 相似文献
79.
In this work, a novel hybrid fibrous vehicle was developed for the release and real-time detection of nitric oxide (NO). The vehicle consisted of poly(L-lactide)/chitosan (PLLACS), cadmium tellurium quantum dots (CdTe QDs), and conjugating S-nitrosothiols. CdTe QDs were placed on the surface of PLLACS fibers as NO fluorescent probes through coaxial electrospinning; in this method, the PLLACS was used as filament material. Water-dispersible CdTe QDs were synthesized using mercaptoacetic acid as a stabilizer. The amino groups of chitosan served as reactive sites where chitosanbased S-nitrosothiols were formed. The fibrous PLLACS-QDs-NO composite was found to release NO under UV. The released NO could be detected in real time on the basis of the fluorescence quenching mechanism of QDs. These PLLACSQDs-NO nanofibers provide insights into novel designs of biocompatible NO delivery systems. 相似文献
80.
Ana Flavia Camara Bezerra Laura Hecker de Carvalho Wilma Sales Cavalcanti Antonio Gilson Barbosa 《Fibers and Polymers》2016,17(11):1908-1915
Composites were prepared with 13, 23 30 and 40 % fiber and evaluated the mechanical performance in tensile, flexural and impact. The mechanical properties of these composites were also evaluated function of time at 110 °C thermal exposure. Caroa fibers were characterized by techniques such as thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the best mechanical properties were achieved for composites containing 23 to 30 % fiber. The incorporation of 23 % fiber caroa increased both the modulus of elasticity in the tensile test as the flexural strength and impact, the composite with 30 % fiber caroa showed higher tensile strength. The results show that the tensile and flexural strength of the composite decreased with time of thermal exposure. The thermal aging at 110 °C caused a decrease in tensile properties of the composites. 相似文献