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Genetic Improvement of Rice for Bacterial Blight Resistance:Present Status and Future Prospects

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Rice science 2022年第2期29卷 118-132页

作者： R.ABDUL FIYAZ D.SHIvANI k.CHAITHANYA k.MOUNIkA M.CHIRANJEEvI G.S.LAHA B.C.vIRAkTAMATH L.v.SUBBA rao R.M.SUNDARAM ICAR-Indian Institute of Rice Research RajendranagarHyderabad 500030India Professor Jayashankar Telangana State Agricultural University RajendranagarHyderabad 500030India

The production and productivity of rice has been challenged due to biotic and abiotic *** blight(BB)disease,caused by Xanthomonas oryzae ***,is one of the important biotic stress factors,which reduces rice production by 20%-50%.The deployment of host plant resistance is the most preferred strategy for management of BB disease,and breeding disease resistant varieties remains a very economical and effective ***,it is difficult to develop rice varieties with durable broad-spectrum resistance against BB using conventional approaches *** biotechnological tools,particularly the deployment of molecular markers,have facilitated the cloning,characterization and introgression of BB resistance genes into elite *** least 46 BB resistance genes have been identified and mapped from diverse sources till *** these,11 genes have been cloned and ***-assisted breeding remains the most efficient approach to improve BB resistance by introducing two or more resistance genes into target *** the identified genes,xa5,xa13 and Xa21 are being widely used in marker-assisted breeding and more than 70 rice varieties or hybrid rice parental lines have been improved for their BB resistance alone or in combination with genes/QTLs conferring tolerance to other *** review the developments related to identification and utilization of various resistance genes to develop BB resistant rice varieties through marker-assisted breeding.

关键词： rice bacterial blight resistance gene marker-assisted breeding gene pyramiding

Association between cag-pathogenicity island in Helicobacter pylori isolates from peptic ulcer,gastric carcinoma,and non-ulcer dyspepsia subjects with histological changes

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World Journal of Gastroenterology 2005年第43期11卷 6815-6822页

作者： Mahaboob Ali Aleem A khan Santosh k Tiwari Niyaz Ahmed L venkateswar rao CM Habibullah Center for Liver Research and Diagnostics Pathogen Evolution Group Department of Microbiology

AIM： To investigate the presence of the cag-pathogenicity island and the associated histological damage caused by strains with complete cag-PAI and with partial deletions in correlation to the disease status. METHODS： We analyzed the complete cag-PAI of 174 representative Helicobacter pylori （H pylori ） clinical isolates obtained from patients with duodenal ulcer, gastric ulcer, gastric cancer, and non-ulcer dyspepsia using eight different oligonucleotide primers viz cagA1, cagA2, cagAP1, cagAP2, cagE, cagT, LEC-1, LEC-2 spanning five different loci of the whole cag-PAI by polymerase chain reaction （PCR）. RESULTS： The complete screening of the genes comprising the cag-PAI showed that larger proportions of subjects with gastric ulcer （97.8%） inhabited strains with complete cag-PAI, followed by gastric cancer （85.7%）, non-ulcer dyspepsia （7.1%）, and duodenal ulcer （6.9%）, significant differences were found in the percentage distribution of the genes in all the clinical groups studied. It was found that strains with complete cag-PAI were able to cause severe histological damage than with the partially deleted ones. CONCLUSION： The cag-PAI is a strong virulent marker in the disease pathogenesis as it is shown that a large number of those infected with strain with complete cag-PAI had one or the other of the irreversible gastric pathologies and interestingly 18.5% of them developed gastric carcinoma. The presence of an intact cag- PAI correlates with the development of more severe pathology, and such strains were found more frequently in patients with severe gastroduodenal disease. Partial deletions of the cag-PAI appear to be sufficient to render the organism less pathogenic.

关键词： Helicobacter pylori cag-pathogenicity island Genetic diversity Gastro-duodenal diseases

A review on ethnobotany,phytochemistry and pharmacology of Fumaria indica(Fumitory)

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Asian Pacific Journal of Tropical Biomedicine 2012年第8期2卷 665-669页

作者： Prakash Chandra Gupta Nisha Sharma Ch v rao University Institute of Pharmacy Chhatrapati Shahu Ji Maharaj University National Botanical Research Institute

Fumaria indica(Hausskn.) Pugsley(Fumariaceae),known as "Fumitory",is an annual herb found as a common weed all over the plains of India and *** whole plant is widely used in traditional and folkloric systems of *** traditional systems of medicine,the plant is reputed for its anthelmintic,diuretic,diaphoretic,laxative,cholagoguc,stomachic and sedative activities and is used to purify blood and in liver obstruction in ethnopharmacology. The whole plant is ascribed to possess medicinal virtues in Ayurvedic and Unani systems of medicine and is also used in preparation of important Ayurvedic medicinal preparations and polyhedral liver *** review reveals that phytochemical constituents of wide range have been separated from the plants and it possesses important pharmacological activities like smooth muscle relaxant,spasmogenic and spasmolytic,analgesic,anti-inflammatory, neuropharmacological and antibacterial *** separation of hepatoprotective and antifungal constituents from this plant was also reported *** review highlights the traditional,ethnobotanical,phytochemical,pharmacological information available on Fumaria indica,which might be helpful for scientists and researchers to find out new chemical entities responsible for its claimed traditional uses.

关键词： Fumaria indica Phytochemistry Protopine Hepatoprotective

Hydro-elastic computational analysis of a marine propeller using two-way fluid structure interaction

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Journal of Ocean Engineering and Science 2022年第3期7卷 280-291页

作者： v.Rama krishna Srinivas Prasad Sanaka N.Pardhasaradhi B.Raghava rao Naval Science&Technological Laboratory Visakhapatnam532007India Department of Mechanical Engineering V.R.Siddhartha Engineering CollegeVijayawada520007India

Marine propellers have complex geometry and their performance is determined by costly and time consuming open water *** of numerical techniques helps researchers in effective design of *** approaches are used that predicted either hydrodynamic and acoustic response or structural ***-way fluid-structure interaction(FSI)analysis is a very useful approach providing all three responses which helps in the design,analysis and optimization of a *** objective of this paper is to predict the hydro-elastic response of a propeller using two-way FSI on a 0.2m diameter,DTMB-4119 propeller using ANSYS ***-way FSI analysis is carried out using system coupling approach that transfers the data between the structural and fluid *** turbulence effects are captured using the large-eddy simulation(LES)model and the Ffowcs Williams Hawkings(FWH)acoustic model is used for evaluating the sound pressure level(SPL)generated by *** is extended to evaluate the hydro-elastic and acoustic response of the propeller after validating the hydrodynamic performance with the experimental result in the *** results from Two-way FSI analysis are in close agreement when compared with the one-way FSI ***-way FSI can accommodate the peak value of stress and deformation developed during the initial part of the transient solution which is important in the design of *** study reveals that metallic(NAB)propeller can be replaced by a composite *** acoustic response from two-way FSI analysis will be more realistic due to the consideration of hydro-elastic effect of propeller.

关键词： Advance ratio Coupled analysis CFD Marine propeller Hydrodynamic parameters Two-way fluid structure interaction

Microstructure and pitting corrosion of shielded metal arc welded high nitrogen stainless steel

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Defence Technology（防务技术） 2015年第3期11卷 237-243页

作者： RAFFI MOHAMMED G.MADHUSUDHAN REDDY k.SRINIvASA rao Department of Metallurgical Engineering Andhra University Defence Metallurgical Research Laboratory

The present work is aimed at studying the microstructure and pitting corrosion behaviour of shielded metal arc welded high nitrogen steel made of Cromang-N electrode. Basis for selecting this electrode is to increase the solubility of nitrogen in weld metal due to high chromium and manganese content. Microscopic studies were carried out using optical microscopy(OM) and field emission scanning electron microscopy(FESEM). Energy back scattered diffraction(EBSD) method was used to determine the phase analysis, grain size and orientation image mapping. Potentio-dynamic polarization testing was carried out to study the pitting corrosion resistance in aerated 3.5% NaCl environment using a GillAC electrochemical system. The investigation results showed that the selected Cr-Mn-N type electrode resulted in a maximum reduction in delta-ferrite and improvement in pitting corrosion resistance of the weld zone was attributed to the coarse austenite grains owing to the reduction in active sites of the austenite/delta ferrite interface and the decrease in galvanic interaction between austenite and delta-ferrite.

关键词：耐点蚀性能高氮不锈钢焊缝金属电弧焊接研究组织屏蔽场发射扫描电子显微镜奥氏体晶粒

Behaviour of GFRP R.C. Slabs in Flexure in Localenvironment An Experimental Study

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Journal of Civil Engineering and Architecture 2012年第10期6卷 1369-1375页

作者： M. v. venkateshwara rao k. Jagannadha rao M. v. Seshagiri rao P. Jagannadha rao Research Scholar JNTU Hyderabad Andhra Pradesh India Professor of Civil Engineering CBIT Gandipet Hyderabad-75 Andhra Pradesh India Professor of Civil Engineering JNT UniversityHyderabad Kukatpally Hyderabad Andhra Pradesh India Professor of Civil Engineering Ace College of Engg. Hyderabad Andhra Pradesh India

A variety of new materials in the field of concrete technology have been developed during the past three decades with the ongoing demand of construction industry to meet the functional, strength, economical and durability requirements. Though reinforced concrete has high strength and is most widely used construction material it suffers from disadvantages like corrosion of steel, susceptibility to chemical and environmental attack. In order to overcome the above deficiencies of reinforced concrete new materials （special concrete composites） have been developed over the past three decades. Glass Fibre Reinforced Polymer （GFRP） is one such material with wide range of applications. Based on the preliminary investigations on GFRP bars, an optimum fiber/resin ratio of 7：3 was arrived. The tensile strength of GFRP bars is comparable to that of the mild steel as per the tests carried out, but the modulus of elasticity is about 25-30 percentage of that of steel bars. This paper deals with the experimental investigations carried out on small slab panels supported on all four edges with effective spans of 0.9 m ~ 0.45 m, which is a part of large research problem undertaken with different ratios of 10ng span to short span with different support conditions. The test results are compared with similar slab panels reinforced with conventional mild steel bars.

关键词： GFRP bars steel bars corrosion slab panels flexure deflections

Pharmacognostic studies of the leaves and stem of Careya arborea Roxb.

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Asian Pacific Journal of Tropical Biomedicine 2012年第5期2卷 404-408页

作者： Prakash Chandra Gupta Nisha Sharma Ch v rao University Institute of Pharmacy Chhtrapati Shahu Ji Maharaj University Pharmacognosy and Ethnopharmacology Division National Botanical Research Institute

Objective:To study detailed pharmacognostic profile of leaves and stem of Careya arborea(C. arborea) Roxb.(Lecthyidaceae),an important medicinal plant in the Indian system of medicine. Methods:Leaf and stem samples of *** were studied by macroscopical,microscopical, physicochemical,phytochemical,fluorescence analysis of powder of the plant and other methods for standardization recommended by ***:Maeroscopieally,the leaves are simple, broadly obovate in shape,acuminate apex with crenate,dentate margin,petioles(0.1-1.8 cm) long. Microscopically,the leaf showed the presence of median large size vascular bundle covered with fibrous bundle sheath,arrangement of xylem in cup shape and presence of cortical vascular bundle, patches of sclerenchyma,phloem fibers in groups and brown pigment containing cells in stem are some of the diagnostic features noted from anatomical *** microscopy of leaf revealed the presence of parenchyma cells,xylem with pitted vessels and epidermis with anisocylic *** investigations also included leaf surface data;quantitative leaf microscopy and fluorescence analysis. Physiochemical parameters such as loss on drying,swelling index,extractive values and ash values were also determined and results showed that total ash of the stem bark was about two times higher than leaf and water soluble extractive value of leaf and stem bark was two limes higher than alcohol soluble extractive *** phytochemical screening showed the presence of triterpenoids, saponins,tannins and ***:The results of the study can serve as a valuable source of information and provide suitable standards for identification of this plant material in future investigations and applications.

关键词： Careya arborea Microscopy Macroscopy Pharmacognosy Stomata Xylem Phloem Physicochemical

A novel estimation algorithm for torpedo tracking in undersea environment

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Journal of Central South University 2019年第3期26卷 673-683页

作者： D.v.A.N.RAvI kUMAR S.kOTESWARA rao k.PADMA RAJU Department of ECE GVPCEW Department of ECE KLEF Department of ECE JNT University

A novel estimation algorithm is introduced to handle the popular undersea problem called torpedo tracking with angle-only measurements with a better approach compared to the existing filters. The new algorithm produces a better estimate from the outputs produced by the traditional nonlinear approaches with the assistance of simple noise minimizers like maximum likelihood filter or any other algorithm which belongs to their family. The introduced method is extended to the higher version in two ways. The first approach extracts a better estimate and covariance by enhancing the count of the intermediate filters, while the second approach accepts more inputs so as to attain improved performance without enhancement of the intermediate filter count. The ideal choice of the placement of towed array sensors to improve the performance of the proposed method further is suggested as the one where the line of sight and the towed array are perpendicular. The results could get even better by moving the ownship in the direction of reducing range. All the results are verified in the MATLAB environment.

关键词： estimation algorithm torpedo tracking angle-only measurements line of sight maximum likelihood filter

Thin Layer Chromatographic Study of Bauxite and Quantitative Estimation of Co-Existing Al^(3+), Fe^(2+) and Ti^(4+)

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色谱 2005年第5期23卷 555-561页

作者： MOHAMED NAJAR P A JEURkAR J U RAMANA rao k v Jawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 IndiaJawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 IndiaJawaharlal Nehru Aluminium Research Development and Design Centre Nagpur 440 023 India

Thin layer chromatography in combination with spectrophotometry and titrimetry has been used to evaluate chromatographic characteristics of bauxite constituents. The retention behaviors of four major constituents (Al 3+ , Fe 2+ , Ti 4+ , Si 4+ ) in bauxite mineral have been examined on plain and modified layers of silica gel G, silica gel H and cellulose with mobile phases containing aqueous sodium chloride, formic acid and hydrochloric acid. Ternary separation of Al-Fe-Ti was achieved on chromatographic plates made of silica gel H. The pH effect and presence of impurity elements in samples, nature of stationary phases on the ternary separation and detection limits of bauxite constituents were studied. Silicon in bauxite was detected on cellulose plates. Quantitative determinations of Al 3+ , Fe 2+ and Ti 4+ on silica gel H impregnated with sodium formate layers were achieved by titrimetry and spectrophotometry.

关键词：铝土矿主成分共存离子 Ti^4+ Al^3+ Fe^2+ 薄层色谱法