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11.
Rashmi Kumari Hirokazu Ito Masahiro Takatani Miho Uchiyama Tadashi Okamoto 《Journal of Wood Science》2007,53(6):470-480
Although wood/cellulose-plastic composites (WPC) of low wood/cellulose content have been more accepted worldwide and are promoted
as low-maintenance, high-durability building products, composites containing high wood/cellulose content are not yet developed
on an industrial scale. In this study, flow properties, mechanical properties, and water absorption properties of the compounds
of cellulose microfiber/polypropylene (PP) and maleic anhydride-grafted polypropylene (MAPP) were investigated to understand
effects of the high cellulose content and the dimensions of the cellulose microfiber. The molding processes studied included
compression, injection, and extrusion. It was found that fluidity is not only dependent on resin content but also on the dimension
of the filler; fluidity of the compound declined with increased fiber length with the same resin content. Dispersion of the
composite was monitored by charge-coupled device (CCD) microscope. Increasing the plastic content in the cellulose-plastic
formulation improved the strength of mold in addition to the bond development between resin and filler, and the tangle of
fibers. The processing mode affected the physicomechanical properties of the cellulosic plastic. Compression-molded samples
exhibited the lowest modulus of rupture (MOR) and modulus of elasticity (MOE) and the highest water absorption, while samples
that were injection-molded exhibited the highest MOR (70 MPa) and MOE (7 GPa) and low water absorption (2%). 相似文献
12.
Dietary levamisole modulates the immune response and disease resistance of Asian catfish Clarias batrachus (Linnaeus) 总被引:2,自引:0,他引:2
In order to determine the immunomodulatory effect of dietary levamisole in Asian catfish (Clarias batrachus), fish were fed four different diets for 10 days: a formulated diet as control and the same diet supplemented with 50, 150 or 450 mg levamisole kg?1 feed. The serum bacterial agglutination titre against Aeromonas hydrophila as a measure of specific immunity, serum haemagglutination titre, natural haemolytic complement activity (ACH50), myeloperoxidase and lysozyme activities, total protein level and oxidative radical production by neutrophils as a measure of non‐specific immunity as well as disease resistance against A. hydrophila challenge to separate vaccinated and non‐vaccinated groups were evaluated at 0, 1, 2 and 3 weeks after last administration of levamisole. Levamisole supplement at the lowest level (50 mg kg?1) significantly enhanced oxidative radical production and serum myeloperoxidase (MPO) content immediately after 10 days of feeding, which reached peak values after 3 and 2 weeks of feeding respectively. Haemolytic complement and haemagglutination titre were significantly enhanced after 3 and 1 weeks respectively. Haemolytic complement activity and MPO activities were significantly raised to 150 mg kg?1 after 3 and 2 weeks, respectively. At the highest level of levamisole feeding (450 mg kg?1) significant decreases in superoxide production and complement activity were measured immediately after levamisole feeding, which returned to the normal level after 1 week post‐ feeding. Fish were challenged with a virulent strain of A. hydrophila at 0, 1, 2 and 3 weeks after levamisole feeding, and the cumulative per cent survival was recorded over 10 days. Feeding levamisole at 50, 150 or 450 mg kg?1 increased per cent survival in vaccinated fish immediately after levamisole feeding, and survival was significantly higher at 450 mg kg?1. There was no difference in mortality patterns in non‐vaccinated fish. The results support the use of levamisole at 50 mg kg?1 feed for 10 days as an immunostimulant in Asian catfish farming. 相似文献
13.
Kumari Madhu Kumar Vikas Kaur Ramandeep Kumar Satish Sharma Rakesh 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):241-249
Plant Foods for Human Nutrition - Ficus geniculata (FG) is one of the underutilized fig species in India and throughout the world. However, the different parts of the plant have numerous... 相似文献
14.
D. M. De Costa R. M. P. S. Rathnayake W. A. J. M. De Costa W. M. D. Kumari D. M. N. Dissanayake 《Journal of Agronomy and Crop Science》2006,192(3):209-220
Anatomical and physiological characters of the leaf surface and its physico‐chemical environment substantially influence the density and diversity of phyllosphere‐inhabiting microorganisms, which may include natural antagonists of important pathogens. The objective of this investigation was to quantify the phyllosphere (i.e. leaf surface) microbial population in a range of rice varieties grown in Sri Lanka and to identify the leaf anatomical and physiological characters that determine the density and diversity of phyllosphere microbes. Fifteen rice varieties including both traditional and new high‐yielding varieties were used in a planthouse experiment and a field experiment in two consecutive seasons to quantify the phyllosphere microbial population and measure leaf characters that may influence it. There were highly significant intervarietal variations in the density and diversity of epiphytic bacterial, fungal and total microbial populations under both planthouse and field conditions. However, there was no difference between traditional and new, high‐yielding varieties in their capacity to harbour epiphytic microbes in the phyllosphere. Total microbial density (TMD) under both conditions showed positive correlations with leaf hair density, stomatal density and transpiration rate. Under planthouse conditions, TMD was also positively correlated with leaf hair length and negatively correlated with leaf temperature. These correlations can be explained in terms of providing favourable microsites on the phylloplane for epiphytic microbial growth. 相似文献
15.
QTL analysis of morphological and developmental traits in the Ler × Cvi population of Arabidopsis thaliana 总被引:1,自引:0,他引:1
Champa Kumari Bandaranayake Rachil Koumproglou Xiao Yu Wang Timothy Wilkes Michael John Kearsey 《Euphytica》2004,137(3):361-371
Drought frequently constrains production of wheat (Triticum aestivum L.), but development of tolerant cultivars is hampered by low heritability for drought tolerance and a lack of effective
selection strategies. Our objective was to identify an optimum selection regime for wheat in drought-prone environments. Six-hundred
entries derived from 10 crosses were developed by selection under continuous high moisture, alternating high with low moisture,
alternating low with high moisture, and continuous low moisture conditions for five generations. The selections were evaluated
in two low-yield, a medium-yield, and a high-yield environment in the Yaqui Valley, Sonora, Mexico. The mean performance of
entries derived from a particular selection regime was dependant on the stress level of the evaluation environment. Lines
developed and selected under continuous high moisture and continuous low-moisture regimes produced the highest mean yields
in the low moisture evaluation environment. There was no relationship between continuous selection under either high yielding
conditions or low yielding conditions and the mean performance of the resultant lines in their respective high and low yielding
evaluation environments. The mean yield of lines selected using the alternating high/low moisture regime as well as the five
highest yielding lines were superior in the HY environment, and had similar performance with other regimes under the low yielding
evaluation environment. Our results indicate that alternating selection between high and low yielding environments is the
most effective way to develop wheat germplasm adapted to environments where intermittent drought occurs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
17.
Biochemical characterization of amandin,the major storage protein in almond (Prunus dulcis L.) 总被引:1,自引:0,他引:1
Sathe SK Wolf WJ Roux KH Teuber SS Venkatachalam M Sze-Tao KW 《Journal of agricultural and food chemistry》2002,50(15):4333-4341
The almond major storage protein, amandin, was prepared by column chromatography (amandin-1), cryoprecipitation (amandin-2), and isoelectric precipitation (amandin-3) methods. Amandin is a legumin type protein characterized by a sedimentation value of 14S. Amandin is composed of two major types of polypeptides with estimated molecular weights of 42-46 and 20-22 kDa linked via disulfide bonds. Several additional minor polypeptides were also present in amandin. Amandin is a storage protein with an estimated molecular weight of 427,300 +/- 47,600 Da (n = 7) and a Stokes radius of 65.88 +/- 3.21 A (n = 7). Amandin is not a glycoprotein. Amandin-1, amandin-2, and amandin-3 are antigenically related and have similar biochemical properties. Amandin-3 is more negatively charged than either amandin-1 or amandin-2. Methionine is the first essential limiting amino acid in amandin followed by lysine and threonine. 相似文献
18.
Kar A Jacquier JC Morgan DJ Lyng JG McKenna BM 《Journal of agricultural and food chemistry》2005,53(21):8259-8264
The influence of the lipid extraction process on both macroscopic and microscopic characteristics of nonwaxy rice starch gelatinization in excess water was examined. Surface lipids extraction did not change the thermodynamics of starch gelatinization but lead to a significant reduction (33%) in the enthalpy of starch-lipid complex melting at high temperature, resulting in less viscous dispersions. Internal lipid extraction using hot aqueous alcoholic solutions resulted in an irreversible increase in starch granule diameter (50% increase in D[4,3]) and a dramatic change in cooking characteristics of the starch. Instead of the bimodal swelling observed for native nonwaxy rice starch, only one broad transition in swelling, solubility, granule size, and viscosity was observed in the case of the totally defatted starch. While the total removal of lipids resulted in a slight increase in starch swelling at intermediate temperatures, the harshness of the process caused irreparable changes leading to notably lower swelling at high temperatures. 相似文献
19.
Monika Vilkienė Dalia Ambrazaitienė Danutė Karčauskienė Zenonas Dabkevičius 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(8):641-646
ABSTRACTMineralization is the main organic matter conversion process, which leads not only to preservation of organic matter in the soil but also to its sequestration. Soil organic matter has equal value as mineral part if we want to improve soil quality or increase the yield. Because of intensive farming, irresponsible use of mineral fertilizers and natural factors, soil organic matter is decreasing. To counteract this process, different soil-friendly management practices and techniques, such as shallow tillage, no-tillage or direct drilling and application of additional organic matter are used. The objective of the present study was to assess the changes in the intensity of soil organic matter mineralization as influenced by primary soil tillage of different intensity in combination with organic matter incorporation. Long-term studies showed that land management practices differentiated the soil into two layers: upper (0–10?cm) layer containing more moisture and nutrients and lower (10–20?cm) layer comprising less moisture and nutrients. The conditions of aeration in the arable soil layer did not change under the effect of ploughing. In this soil, the rate of mineralization was lower than that in the ploughless tillage treatment. The most active mineralization of soil organic matter in the ploughless tillage treatment occurred in the autumn period, when high level of rainfall promoted the loss of nutrients from the topsoil layer. 相似文献
20.