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941.
Soil slaking is an environment-friendly technique that is gaining importance in restoring saline soils. The objective of this
article is to evaluate the effect of initial water content (IWC) on saturated hydraulic conductivity (K
s) in desalinization with slaking and drying. Accordingly, a slaking test was carried out during February, 2009 for evaluating
the effects of slaking and drying on K
s, sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP) under various IWC. We prepared natural and air-dried
soils of paddy field in Kojima Bay Polder, Japan to give different pre-drying, air-dried, and not dried (natural). The air-dried
soils were resaturated. Each soil was well mixed, then dried to different initial moisture contents (60, 50, 40, 30, 20, and
10% by weight). The specimens were immersed into water in the pot for 24 h. The K
s was measured, and cations in slaked and unslaked soils were analyzed. The K
s was high under the water content below 30% in both the natural and the air-dried soils. But the effects were more pronounced
in the natural soil. The air-dried soil showed far smaller K
s than the natural soil. In outer solution, the highest SAR was noted at 30% in the natural and 30 and 20% in the air-dried
soils. Significant decrease in ESP of the soils (slaked + unslaked) was also observed at the same water content. Lower water
content was more effective in decreasing the soil ESP after desalinization from saline soil. The natural soil showed lower
ESP and higher porosity, which was considered as a reason for higher K
s of natural soil than that of air-dried soils. The results indicated that lower water content (10–30%) had no hazardous effect
on K
s by slaking and drying of soil. 相似文献
942.
Hyun Ah Jung Md. Nurul Islam Chan Mee Lee Hyong Oh Jeong Hae Young Chung Hee Chul Woo Jae Sue Choi 《Fisheries Science》2012,78(6):1321-1329
In the present study, we investigated the antidiabetic potential of fucoxanthin via the inhibition of rat lens aldose reductase (RLAR), human recombinant aldose reductase (HRAR), advanced glycation end-product (AGE) formation, protein tyrosine phosphatase 1B (PTP1B), and α-glucosidase. Fucoxanthin displayed potent inhibitory activity against AGE formation and HRAR and RLAR activity. In addition, fucoxanthin showed potent inhibitory activity against PTP1B. However, it did not show α-glucosidase inhibitory activity below 200 μM. In addition, our kinetic study revealed that fucoxanthin competitively inhibited RLAR, while it showed mixed-type inhibition against PTP1B. In order to confirm enzyme inhibition, we predicted the 3D structure of PTP1B using Autodock 4.0 to simulate the binding of fucoxanthin. Docking simulation results demonstrated that three residues of PTP1B (Phe30, Phe52, and Gly183) interact with the two hydroxyl groups of fucoxanthin. In addition, the binding energy was negative (?7.66 kcal/mol), indicating that the three hydrogen bonds may stabilize the open form of the enzyme and potentiate tighter binding to the active site of PTP1B, resulting in more effective PTP1B inhibition. The results of the present study therefore clearly demonstrate the promising potential of fucoxanthin as a therapeutic intervention for the management of diabetes as well as diabetes-associated complications, which could be explored further. 相似文献
943.
Md. Iqbal Faruk Masatoshi Izumimoto Nobuhiro Suzuki 《Journal of General Plant Pathology》2008,74(6):425-433
The type virus of the family Hypoviridae,
Cryphonectria hypovirus 1 strain EP713 (CHV1-EP713), infects Cryphonectria parasitica, the filamentous causal fungus of chestnut blight, and reduces its virulence. This pathosystem serves as a model to study
fungus-mycovirus interactions. We previously developed a genetic screening protocol for host factors associated with symptom
induction by CHV1-EP713 and its mutants. In the procedure the standard field fungal isolate EP155 was transformed by cDNA
from a mild hypovirus mutant Cys(72), launching virus infection, and mutagenized by random plasmid insertion with pHygR conferring
hygromycin resistance. We now report an extension of the study to characterize different mutant strains, with different phenotypes
than their parental strain TCys(72)-1. TCys(72)-1 is moderately reduced in pigmentation and sporulation compared to the uninfected
wild-type strain EP155. Mutants sfb1, sfb2 and k202 were characterized biologically and molecularly in comparison to the previously
isolated mutant (namA) and the parental strain. These mutants harbored one (sfb1) or more copies (sfb2 and k202) of the mutagenic plasmid, pHygR.
The three mutants had similar biological attributes; that is, vegetative growth rate, conidiation and virulence (assay on
apples) was reduced on potato dextrose agar media, relative to the parental strain and pigmentation was the same or slightly
increased. Interestingly, viral dsRNA accumulation levels were apparently unaltered in these mutants. The screening method
was efficient for mining fungal mutants with unusual hypovirus symptoms. Further, characterization of the mutants provides
interesting insights into symptom induction by the hypovirus. 相似文献
944.
Abdul Majid Ayatollahi Mustafa Ghanadian Suleiman Afsharypuor Muhammad Iqbal Choudhary Farzad Kobarfard Mohammad Rahmati 《Fitoterapia》2010
Euphorbia aellenii Rech. f. (Euphorbiaceae) afforded a cytotoxic chloroform fraction from which two new esters of 6(17)-epoxylathyrol were identified (1 and 2). The structure of these compounds was elucidated by spectroscopic methods. 相似文献
945.
Homegardens around the world often exhibit remarkable variation in composition and structure depending on the physiographic
and climatic conditions of the area and a wide variety of household characteristics. This research investigated whether households’
contextual attributes have a quantitative and predictable relationship with homegarden vegetation structure from a total of
402 randomly selected households in southwestern Bangladesh. The central analytical tool to test the relationship between
household characteristics and the homegarden vegetation structure was multiple regression. The moderate to low regression
R
2 values revealed that most household characteristics were not strong predictors of homegarden vegetation structure. Despite
the weak explanatory power of the majority household characteristics, time spent and homestead size had the strongest relationship
with species richness and income in a homegarden. Households being the main source of labor for a majority of households suggest
that outside labor shortage would not influence homegarden vegetation structure. We suggest that women’s active participation
in homegardening activities to reduce gender inequality in the family which will perhaps result in more diverse and economically
viable homegarden. However, increasing population density and the concomitant fragmentation of landholdings to homesteads
may create opportunity for homegarden promotion in Bangladesh. Our results of decreased species richness in the homegarden
with improved roads and proximity to market support the general hypothesis of subsistence homegardens and did not reinforce
the general fears of gradual decline in species richness due to a market economy. Household characteristics had no influence
on the presence of IUCN Red Listed species in the homegarden, except for gender and education of the household head. However,
most homegardeners were unaware about the status of red listed species, suggesting that occurrence of red listed species in
homegardens was by chance. Thus, efforts to improve awareness and to save and conserve rare species from extirpation are needed. 相似文献
946.
Two medicinally important seed oils viz. Mimusops elengi and Parkinsonia aculeata were analyzed for fatty acids distribution pattern in triacylglycerols using pancreatic lipase hydrolysis method. The seed oils contain high percentage of unsaturated acids (M. elengi 64.8% and P. aculeata 82.7%). The lipolytic data revealed that linoleic acid dominates at 2-position of triacylglycerols of all seed oils. M. elengi contain erucic acid in small amount (0.3%). 相似文献
947.
Sayma Akhter Md. Abdul Halim Md. Shawkat Islam Sohel Swapan Kumar Sarker Mohammad Shaheed Hossain Chowdhury Sanjay Saha Sonet 《林业研究》2008,19(1):72-78
This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and using patterns for hair care, facial treatments and body care, were summarized in 13 tables. This paper accumulate the scattered knowledge regarding the use of plants in beauty-care in Bangladesh, to draw the extent of use of NTFPs in health care and to record the knowledge for assessing the possibilities of further implementation in herbal cosmetics industries. The structured knowledge can be used in policy making process for sustainable management of these valuable NTFPs leading to the conservation of the country's biological diversity. It is suggested that intensive field level research is necessary for securing sustainability of NTFPs. 相似文献
948.
Mohammad Shaheed Hossain Chowdhury ;Md. Abdul Halim ;Nur Muhammed ;Farhana Haque ;Masao Koike 《林业研究》2008,19(3):245-251
A study was conducted to explore the traditional utilization pattern and indigenous management practices of wild date palm (Phoenix sylvestris Roxb) in the rural agrarian regions of Bangladesh. A multistage sampling method with 10% intensity and a semi-structured questionnaire were used for the study. The farmers manage the palm mainly for sap production with which sugar based secondary goods are manufactured. The sap is either used fresh as drink or after some sort of processing as molasses and/or alcoholic beverage. Seven diversified sites support the palm as its habitat and most palms (20.40%) occur in orchards. Besides growing naturally, the palm is also established in orchards using the wildings as the staple planting material. Although the medium category farmers own most of the palms (33%), a considerable portion (28.68%) of it is managed by the landless farmers, who earn a substantial livelihood from the palms. The farmers practice their own indigenous wisdom in every stage of the palm's maintenance from planting through tapping for sap collec- tion to the processing of products. If managed more scientifically on a sustainable basis with the collaboration of farmers' indigenou~ knowledge, this familiar palm could be able to support the rural economy of the country to a great extent. Side by side, it would also be able to contribute to the richness of biodiversity in the region. 相似文献
949.
We studied the effects of line thinning on stand structure, microclimate and understory species diversity of two Cryptomeria japonica D. Don plantations in south-central Japan. In each of two study sites we compared stand structure between the thinned stand
and an adjacent unthinned stand and found that line thinning increased the growth rate of residual trees such that stand basal
area may recover within 10 years after thinning. In the thinned stand, more open canopy conditions resulted in higher maximum
temperatures on the forest floor during the early growing season than in the unthinned stand. The thinned stand had greater
understory plant species richness and biomass than the unthinned stand. This study suggested that line thinning could potentially
enhance biodiversity while simultaneously increasing tree-growth rates in overstocked Cryptomeria japonica plantations. 相似文献
950.
Aphidicidal activity of hot and cold water extracts of some indigenous plants, Azadirachta indica A. Juss (neem), Calotropis procera (Aiton) W.T. Aiton (akanda), Polygonum hydropiper L. (biskatali) and Ipomoea sepiaria J. Koenig ex Roxb. (bankalmi), were tested against the bean aphid, Aphis craccivora Koch. Hot water extract of P. hydropiper and A. indica was found to be the most effective (87.6–94.5 and 80.47–89.6% mortality respectively, P < 0.01) among all the extracts. Other hot and cold water extracts also appeared to be useful (59.5–87.5% mortality) as pesticides
for A. craccivora. The highest yield (3.25 kg per plant) was obtained using hot water extract of P. hydropiper followed by hot water extract of A. indica (3.15 kg per plant). The lowest yield (0.32 kg per plant) was recorded from the control block. All the phytoproduct treatments
had significantly (P < 0.01) better yield than the control block. 相似文献