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101.
Tariq Mahmood Muhammad H. Rahman Gary R. Stringam Francis Yeh Allen G. Good 《Euphytica》2007,154(1-2):101-111
A doubled haploid population of Brassica juncea, developed from a cross between two parental lines differing for days to maturity, was used to study the efficiency of indirect
selection for a primary trait through selection of secondary trait(s) over direct selection for the primary trait when quantitative
trait loci information is available for both primary and secondary traits, and applied. Days to maturity was considered as
primary trait, while days to first flowering, days to end of flowering, flowering period and plant height were considered
as secondary traits. An RFLP linkage map was employed for QTL analysis of maturity and maturity-determinant traits, and a
stable QTL B6 simultaneously affecting these two types of traits was identified. This linked QTL explained 11.7% phenotypic
variation for days to maturity, 20.7% variation for days to first flowering, 24.3% variation for days to end of flowering
and 14.4% variation for plant height. Phenotypic evaluation of maturity and/or maturity-determinant traits, viz. days to first
flowering, days to end of flowering and plant height revealed that limited genetic advance for early maturity can be achieved
through phenotypic selection of the primary and/or the secondary trait(s). However, the estimates of genetic advance for early
maturity based on combined phenotypic evaluation and linked QTL data was found to be, at least, three times higher compared
to genetic advance based on phenotypic evaluation only, demonstrating the potential of marker-assisted selection in breeding
for early maturity in B. juncea. 相似文献
102.
103.
Entropy and kriging approach to rainfall network design 总被引:2,自引:0,他引:2
Hydrological data are the basic ingredients for planning, constructing, and operating of hydraulic structures. A well-designed
rainfall network can accurately provide and reflect the information of rainfall in a catchment. However, in past studies,
the required number and optimal location of rain gauge stations have yet to produce a satisfactory result. A more accurate
design is required. Hence, in this study, a proposed model composed of kriging and entropy with probability distribution function
is introduced to relocate the rainfall network and to obtain the optimal design with the minimum number of rain gauges. The
ordinary kriging is used to generate rainfall data of potential locations where rain gauge stations may be installed. The
information entropy based on probability is used to measure the uncertainty of rainfall distribution. The probability distribution
function will be introduced to fit the statistical characteristics of data of the rain gauges. By calculating the joint entropy
and the transferable information, the relocated rain gauges are prioritized and the minimum number and location of the rain
gauges in the catchment can be obtained to construct the optimal rainfall network to replace the existing rainfall network. 相似文献
104.
The development of alveolar bone adjacent to the tooth root during tooth eruption is not well understood. This study tested the hypothesis that predominantly woven bone forms adjacent to tooth roots during tooth eruption, but that this immature structure transitions to lamellar bone when the tooth comes into function. Additionally, bone resorption was predicted to play a key role in transitioning immature bone to more mature, load-bearing tissue. Miniature pigs were compared at two occlusal stages, 13 weeks (n = 3), corresponding with the mucosal penetration stage of M(1) tooth eruption, and 23 weeks (n = 3), corresponding with early occlusion of M(1) /M(1) . Bone samples for RNA extraction and qRT-PCR analysis were harvested from the diastema and adjacent to M(1) roots on one side. Following euthanasia, bone samples for haematoxylin and eosin and TRAP staining were harvested from these regions on the other side. In contrast to expectations, both erupting and functioning molars had reticular fibrolamellar structure in alveolar bone adjacent to M(1) . However, the woven bone matrix in older pigs was thicker and had denser primary osteons. Gene expression data and osteoclast cell counts showed a tendency for more bone resorptive activity near the molars than at distant sites, but no differences between eruptive stages. Thus, although resorption does occur, it is not a primary mechanism in the transition in alveolar bone from eruption to function. Incremental growth of existing woven bone and filling in of primary osteons within the mineralized scaffold generated the fortification necessary to support an erupted and functioning tooth. 相似文献
105.
Kunkalikar SR Poojari S Arun BM Rajagopalan PA Chen TC Yeh SD Naidu RA Zehr UB Ravi KS 《Phytopathology》2011,101(3):367-376
A survey for Peanut bud necrosis virus (PBNV), Watermelon bud necrosis virus (WBNV), Capsicum chlorosis virus (CaCV), and Iris yellow spot virus (IYSV) was conducted between 2002 and 2009 in the major vegetable-growing areas in India. PBNV was documented widely in tomato and chili peppers in 14 states representing southern, north-western, north-eastern, and central regions and WBNV was predominantly detected in watermelons and cucurbits in all except north-eastern regions. In addition, the expanded host range of PBNV to watermelons and other cucurbits and WBNV to tomato and chili peppers was observed leading to natural mixed infection of the two viruses. IYSV was found in onion in southern, central, and north-eastern regions and CaCV in tomato and chili peppers in northern and southern regions, respectively. Phylogenetic analysis of the nucleocapsid gene revealed segregation of field isolates of PBNV and WBNV into two distinct subclades, whereas isolates of CaCV and IYSV each clustered into a single clade. A proposal for establishing WBNV as a distinct tospovirus species is made based on the molecular characterization of small- (S) and medium- (M) RNA segments. 相似文献
106.
Kuo HP Chuang TC Yeh MH Hsu SC Way TD Chen PY Wang SS Chang YH Kao MC Liu JY 《Journal of agricultural and food chemistry》2011,59(15):8216-8224
Berberine (BBR) is a natural alkaloid with significant antitumor activities against many types of cancer cells. This study investigated the molecular mechanisms by which BBR suppresses the growth of HER2-overexpressing breast cancer cells. The results show that BBR induces G1-phase cell cycle arrest by interfering with the expression of cyclins D1 and E and that it induces cellular apoptosis through the induction of a mitochondria/caspase pathway. The data also indicate that BBR inhibits cellular growth and promotes apoptosis by down-regulating the HER2/PI3K/Akt signaling pathway. Furthermore, it is also shown that a combination of taxol and BBR significantly slows the growth rate of HER2-overexpressing breast cancer cells. In conclusion, this study suggests that BBR could be a useful adjuvant therapeutic agent in the treatment of HER2-overexpressing breast cancer. 相似文献
107.
Shieh JP Cheng KC Chung HH Kerh YF Yeh CH Cheng JT 《Journal of agricultural and food chemistry》2011,59(8):3747-3753
Catalpol is one of the active principles from roots of Rehmannia glutinosa Steud (Scrophulariaceae) that is widely used to treat diabetic disorders in Chinese traditional medicine using the name of Di-Huang, which is used to investigate the mechanisms for lowering of plasma glucose in streptozotocin-induced diabetic rats (STZ-diabetic rats). Catalpol decreased plasma glucose in a dose-related manner, and this action was reduced by pretreatment with naloxone or naloxonazine. An increase of plasma β-endorphin by catalpol was also observed in parallel. The plasma glucose lowering action of catalpol was deleted in bilateral adrenalectomized rats. Moreover, catalpol enhanced β-endorphin release from the isolated adrenal medulla of STZ-diabetic rats. Otherwise, plasma glucose lowering action of catalpol failed to produce in opioid μ-receptor knockout mice. Also, repeated administration of catalpol for 3 days in STZ-diabetic rats resulted in a marked reduction of phosphoenolpyruvate carboxykinase (PEPCK) expression in liver and an increased expression of glucose transporter subtype 4 (GLUT 4) in skeletal muscle. These effects were also reversed by blockade of opioid μ-receptors. Our results suggested that catalpol increased glucose utilization through increase of β-endorphin secretion from adrenal gland in STZ-diabetic rats. 相似文献
108.
Natural water purification systems including oxidation ponds and surface flow wetlands are commonly used to treat wastewater in tropic regions, however, the water quality of the effluent fluctuated and often failed to comply with regulatory water criteria due to algae bloom. Separation of algae is inevitable to produce high effluent quality and to comply with local effluent standards. Algal growth control measures including emergent and floating macrophytes as well as back cloth physical light shading and algaecide application were studied and were aimed to reuse the effluent for water resource conservation and groundwater recharge. The results demonstrated that emergent and free-floating macrophytes light shading on algal growth control were viable in both batch experiments and field-scale hybrid natural water purification systems such as surface flow wetlands. Water quality parameters including COD, turbidity, SS were positively correlated with the algal concentrations and could be used as indictors of the trophic status of aquatic systems. Emergent macrophytes assisted control algal growth by preventing sunlight from reaching the water column in surface flow wetlands. Results of this study can be used by similar hybrid natural water purification systems to control algal activity and to prevent effluent deterioration. 相似文献
109.
Light energy absorbed by the 576 bilin chromophores in the six rods of the phycobilisome of the cyanobacterium Synechocystis 6701 is funneled into a 1.5 x 10(6) dalton core. The 72 bilins of the core function as a single unit with respect to the rate-limiting processes for energy flow within these particles. 相似文献
110.
Neuronal death induced by activating N-methyl-D-aspartate (NMDA) receptors has been linked to Ca2+ and Na+ influx through associated channels. Whole-cell recording from cultured mouse cortical neurons revealed a NMDA-evoked outward current, INMDA-K, carried by K+ efflux at membrane potentials positive to -86 millivolts. Cortical neurons exposed to NMDA in medium containing reduced Na+ and Ca2+ (as found in ischemic brain tissue) lost substantial intracellular K+ and underwent apoptosis. Both K+ loss and apoptosis were attenuated by increasing extracellular K+, even when voltage-gated Ca2+ channels were blocked. Thus NMDA receptor-mediated K+ efflux may contribute to neuronal apoptosis after brain ischemia. 相似文献