Browsing by Author "A.K. Tripathi"

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A Decision Tree Approach for Design Patterns Detection by Subgraph Isomorphism
(2010) Akshara Pande; Manjari Gupta; A.K. Tripathi
In many object oriented softwares, there are recurring patterns of classes. Design pattern instances are important for program understanding and software maintenance.Hence a reliable design pattern mining is required. Here we are applying decision tree approach followed by subgraph isomorphism technique for design pattern detection. © Springer-Verlag Berlin Heidelberg 2010.
A knowledge identification framework for component based dependency analysis process
(2013) Ratneshwer; A.K. Tripathi
Knowledge engineering applied to the Component Based Software Engineering (CBSE) field is an important research area that focuses on identification, specification and validation of knowledge and experiences acquired during various phases of component based software development cycle. This work presents a systematic approach to knowledge identification in dependency analysis process in context of CBSE, which results a well defined approach for representing dependency analysis information in form of knowledge artifacts. The identified knowledge artifacts and knowledge relationships may help in design optimization, fault management, configuration management and testing processes ©2013 SERSC.
A new approach for detecting design patterns by graph decomposition and graph isomorphism
(2010) Akshara Pande; Manjari Gupta; A.K. Tripathi
Design Pattern Detection is a part of many solutions to Software Engineering difficulties. It is a part of reengineering process and thus gives important information to the designer. Design Pattern existence improve the program understanding and software maintenance. With the help of these patterns specific design problem can be solved and object oriented design become more flexible and reusable. Hence a reliable design pattern mining is required. Here we are applying graph decomposition followed by graph isomorphism technique for design pattern detection. © 2010 Springer-Verlag Berlin Heidelberg.
Adenosine diphosphate ribosylation of dinitrogenase reductase and adenylylation of glutamine synthetase control ammonia excretion in ethylenediamine-resistant mutants of Azospirillum brasilense Sp7
(2006) A. Srivastava; A.K. Tripathi
Azospirillum brasilense is a nitrogen-fixing, root-colonizing bacterium that brings about plant-growth-promoting effects mainly because of its ability to produce phytohormones. Ethylenediamine (EDA)-resistant mutants of A. brasilense were isolated and screened for their higher ability to decrease acetylene and release ammonia in the medium. One of the mutants showed considerably higher levels of acetylene decrease and ammonia excretion. Nitrogenase activity of this mutant was relatively resistant to inhibition by NH4Cl. Adenosine triphosphate ribosylation of dinitrogenase reductase in the mutant did not increase even in presence of 10 mM NH4Cl. Although the mutant showed decreased glutamine synthetase (GS) activity, neither the levels of GS synthesized by the mutant nor the NH 4+ -binding site in the GS differed from those of the parent. The main reason for the release of ammonia by the mutant seems to be the fixation of higher levels of nitrogen than its GS can assimilate, as well as higher levels of adenylylation of GS, which may decrease ammonia assimilation. © 2006 Springer Science+Business Media, Inc.
Application of PCR fingerprinting techniques for identification and discrimination of Salmonella isolates
(2001) Anjali Tikoo; A.K. Tripathi; S.C. Verma; N. Agrawal; Gopal Nath
Different PCR-based DNA fingerprinting techniques were evaluated for identification and discrimination of bacterial strains. Fifteen strains of Salmonella enterica subspecies enterica serotypes Typhi (10), Paratyphi A (1) and Typhimurium (3) collected over a period of 15 years from stool, blood, and urine samples and river Ganga were tested. All the strains were analysed by restriction analysis of the amplified 16s rDNA (ARDRA), random amplified polymorphic DNA (RAPD) and BOX-PCR methods. In ARDRA, strains belonging to the same species were identified by identical fingerprints; RAPD on the other hand, divided Salmonella into 9 different groups. Two ciprofloxacin (CIP)-resistant strains showed similar PCR fingerprints which were different from the rest of the 12 strains. In BOX-PCR, all the strains of Salmonella showed 6 different groups which showed the presence of a common band. Serotype Typhimurium could be placed in the same group by BOX-PCR. CIP-resistant strains also produced one characteristic extra band by BOX-PCR. It was observed that RAPD had higher discriminatory power than BOX-PCR and was a simple and rapid technique for use in epidemiological studies of isolates belonging to S. enterica.
Bioremediation of toxic chromium from electroplating effluent by chromate-reducing Pseudomonas aeruginosa A2Chr in two bioreactors
(2002) A. Ganguli; A.K. Tripathi
The chromate-reducing ability of Pseudomonas aeruginosa A2Chr was compared in batch culture, with cells entrapped in a dialysis sac, and with cells immobilized in an agarose-alginate film in conjunction with a rotating biological contactor. In all three systems, the maximum Cr(VI) reduction occurred at 10 mg Cr(VI)/l. Whereas at 50 mg Cr(VI)/l concentration, only 16% of the total Cr(VI) was reduced, five spikings with 10 mg chromate/l at 2-h intervals led to 96% reduction of the total input of 50 mg Cr(VI) /l. Thus maximum Cr(VI) reduction was achieved by avoiding Cr(VI) toxicity to the cells by respiking with lower Cr(VI) concentrations. At 10 mg Cr(VI)/l, the pattern of chromate reduction in dialysis-entrapped cells was almost similar to that of batch culture and 86% of the bacterially reduced chromium was retained inside the dialysis sac. In electroplating effluent containing 100 mg Cr(VI)/l, however, the amount of Cr(VI) reduced by the cells immobilized in agarose-alginate biofilm was twice and thrice the amount reduced by batch culture and cells entrapped in a dialysis sac, respectively.
Cellular stress responses: Preface
(Indian Academy of Sciences, 1998) S.C. Lakhotia; A.K. Tripathi
[No abstract available]
Cyclic alkyl disulphides as tribological additives
(Leaf Coppin Publ Ltd, 2000) V.K. Verma; R. Singh; A. Bhattacharya; A.K. Tripathi
The use of sulphurized natural oils, fats, hydrocarbons, terpenes and aromatic sulphides, disulphides and polysulphides, as antiwear and extreme-pressure lubricant additives, has already been established. However, the potential of cyclic disulphides merits attention. The present paper describes the synthesis and evaluation of 0.5% solutions of certain cyclic disulphides as tribological additives, namely 3-alkylimino-5-(N-methylphenyl)amino-1,2,4-dithiazolines, in paraffin oil, on a four-ball test rig with 12.7 mm diameter steel bearing balls as test specimens. All the additives in general, and 3-propylimino-5-(N-methylphenyl)amino-1,2,4-dithiazoline in particular, exhibited remarkably good antifriction and EP activity, showing a decrease in the coefficient of friction and an appreciable increase in the load-carrying capacity of the lubricant as indicated by a higher load wear index. The wear surface topography of the used test specimen was studied using scanning electron microscopy.
Decolorization of anaerobically digested molasses spent wash by Pseudomonas putida
(2009) M. Ghosh; A. Ganguli; A.K. Tripathi
The distillery wastewater (spent wash) contains dark brown colored recalcitrant organic compounds that are not amenable to conventional biological treatment. The characteristic recalcitrance to decolorization is due to the presence of brown melanoidin polymers. In the present study, feasibility of using Pseudomonas putida putida strain U for decolorization of spent wash was demonstrated. Batch cultures of P. putida decolourized spent wash by 24%, twofold higher decolorization was achieved following immobilization in calcium alginate beads. Glucose concentration was critical for decolourization, and improved color removal efficiency was obtained by periodic replenishment of glucose. Decolourization was also observed with lactose or whey as alternative carbon sources. The results of our study suggest that P.putida could be used for biological decolorization of molasses spent washes and that supplementation with whey (a by-product from cheese industry) can offer economical viability to the process. © 2009 MAIK Nauka.
Design Pattern Detection by normalized cross correlation
(2010) Manjari Gupta; Akshara Pande; Rajwant Singh Rao; A.K. Tripathi
Design Pattern Detection has been documented so far in the literature. The knowledge of design Pattern existence in the program improves the program understanding and software maintenance. Design pattern is a technology for design reuse. Experts store their experiences in the form of design patterns. Reengineering done by novice users will be successful if a reliable design pattern mining exists. There are 23 design patterns defined by experts. Here we are taking the UML diagrams corresponding to design pattern and corresponding to source code. Our main aim is to find out whether a particular design pattern exists in system design (source code) or not. For this we have extracted the relationship graphs (consisting of nodes and edges), and then tried to detect the design pattern. In this paper we have applied normalized cross correlation and taking design pattern as a template tried to find out its existence in system design. Normalized cross correlation (NCC) has been used extensively for many machine vision applications. Normalized cross correlation has been commonly used to evaluate the degree of similarity or dissimilarity between two images. © 2010 IEEE.
Design pattern mining for GIS application using graph matching techniques
(2010) Akshara Pande; Manjari Gupta; A.K. Tripathi
Design Pattern Detection is a part of many solutions to Software Engineering difficulties. It is a part of reengineering process and thus gives important information to the designer. Design Pattern existence improve the program understanding and software maintenance. With the help of these patterns specific design problem can be solved and object oriented design become more flexible and reusable. Hence a reliable design pattern mining is required. A GIS is an information system designed to work with data referenced by spatial / geographical coordinates. Here we are detecting design patterns so that it can be used as a conceptual tool to cope with recurrent problems appearing in the GIS domain. In this way, GIS applications can evolve smoothly, because maintenance is achieved by focusing on different concerns at different times. © 2010 IEEE.
Design pattern mining using state space representation of graph matching
(2011) Manjari Gupta; Rajwant Singh Rao; Akshara Pande; A.K. Tripathi
Design Pattern Detection is a part of many solutions to Software Engineering problems. It is a part of reengineering process and thus gives significant information to the designer. Design Pattern improves the program understanding and software maintenance. Therefore, a reliable design pattern discovery is required. Graph theoretic approaches have been used for design pattern detection in past. Here we are applying state space representation of graph matching algorithm for design pattern detection. State space representation easily describes the graph matching process. Using our approach variants of each design pattern as well as any occurrence of a design pattern can be detected. © Springer-Verlag Berlin Heidelberg 2011.
Diversity of plant growth and soil health supporting bacteria
(2005) K.V.B.R. Tilak; N. Ranganayaki; K.K. Pal; R. De; A.K. Saxena; C. Shekhar Nautiyal; Shilpi Mittal; A.K. Tripathi; B.N. Johri
The global necessity to increase agricultural production from a steadily decreasing and degrading land resource base has placed considerable strain on the fragile agro-ecosystems. Current strategies to maintain and improve agricultural productivity via high-input practices places considerable emphasis on 'fail-safe' techniques for each component of the production sequence with little consideration to the integration of these components in a holistic, systems approach. While the use of mineral fertilizers is considered the quickest and surest way of boosting crop production, their cost and other constraints deter farmers from using them in recommended quantities. In recent years, concepts of integrated plant nutrient management (IPNM) have been developed, which emphasize maintaining and increasing soil fertility by optimizing all possible sources (organic and inorganic) of plant nutrients required for crop growth and quality. This is done in an integrated manner appropriate to each cropping system and farming situation. Improvement in agricultural sustainability requires optimal use and management of soil fertility and soil physical properties, both of which rely on soil biological processes and soil biodiversity. An understanding of microbial diversity perspectives in agricultural context, is important and useful to arrive at measures that can act as indicators of soil quality and plant productivity. In this context, the long-lasting challenges in soil microbiology are development of effective methods to know the types of microorganisms present in soils, and to determine functions which the microbes perform in situ. This review describes some recent developments, particularly in India, to understand the relationship of soils and plants with the diversity of associated bacteria, and traces contributions of Indian scientists in isolating and defining the roles of plant growth promoting bacteria to evolve strategies for their better exploitation.
DNIT - A new approach for design pattern detection
(2010) Akshara Pande; Manjari Gupta; A.K. Tripathi
In many object oriented softwares, there are recurring patterns of classes. With the help of these patterns specific design problem can be solved and object oriented design becomes more flexible and reusable. Design Pattern Detection is a part of solutions to Software Engineering difficulties. Mining of design pattern instances is important for program understanding and software maintenance. Hence a reliable design pattern mining is required. Here we are introducing a new method called DNIT (Depth-Node-Input Table) for design pattern detection, which extracts the design patterns which exists at different depths in the rooted directed graph of system under study. ©2010 IEEE.
Effect of placental-extract gel and cream on non-healing wounds.
(2006) S.K. Tiwary; D. Shukla; A.K. Tripathi; S. Agrawal; M.K. Singh; V.K. Shukla
OBJECTIVE: To compare the effects of topical placental-extract gel and cream in the treatment of chronic non-healing wounds with regard to wound healing and discomfort during dressing change. METHODS: A sample of 120 patients attending the wound clinic at University Hospital, Varanasi, India, with wounds of more than six weeks' duration were enrolled into the study. They were alternately allocated to group A (topical application of placental-extract gel) or group B (placental-extract cream). Wound biopsy was performed, and swab culture and sensitivity were taken. Wound size was measured, and visual analogue scale (VAS) scores for pain and discomfort at dressing change were recorded at weekly follow-up in both groups. Biopsy was repeated after two weeks of treatment and sent for histopathological examination for assessment of angiogenesis in 25 cases from each group. RESULTS: One hundred patients completed the study. More than 50% wound healing was observed after eight weeks in 72% of group A patients and 74% of group B patients (p = 0.75). Microscopic angiogenesis grading system (MAGS) scores were similar in both groups (not statistically significant, p = 0.92). The VAS scores for pain and discomfort were lower in group B (statistically significant, p < 0.02). CONCLUSION: Placental-extract gel and cream are both effective topical agents for chronic non-healing wounds. However, there is less pain and discomfort during dressing change with the placental-extract cream, which we thus recommend for topical application in chronic non-healing wounds.
Enrichment and identification of bacteria capable of reducing chemical oxygen demand of anaerobically treated molasses spent wash
(Blackwell Publishing Ltd, 2004) M. Ghosh; S.C. Verma; A. Mengoni; A.K. Tripathi
Aims: The aim of this study was to isolate and identify bacterial strains capable of using recalcitrant compounds of molasses spent wash as sole carbon source from the soils of abandoned sites of distillery effluent discharge and characterize their ability of reducing the chemical oxygen demand (COD) of the spent wash. Methods and Results: The isolates were grouped into six haplotypes by amplified ribosomal DNA restriction analysis (ARDRA) and BOX-PCR. The phylogenetic position of the representatives of the six main haplotypes strains was determined by 16S rDNA sequencing. They showed maximum similarity to six genera viz. Pseudomonas, Enterobacter, Stenotrophomonas, Aeromonas, Acinetobacter and Klebsiella. The extent of COD (44%) reduced collectively by the six strains was equal to that reduced individually by Aeromonas, Acinetobacter, Pseudomonas and Enterobacter. With spent wash as sole carbon source, the COD reducing strains grew faster at 37°C than 30°C. Conclusions: Bacterial strains capable of degrading some of the recalcitrant compounds of anaerobically digested molasses spent wash can be isolated from the soils of abandoned sites of distillery effluent discharge. Biostimulation of these bacteria, which can degrade 44% of the carbon compounds of anaerobically digested molasses spent wash can be achieved by nitrogen fertilization and relatively higher temperature. Significance and Impact of the Study: Supplementation of nitrogen source and controlling the temperature can be used in evolving strategies for in situ bioremediation of anaerobically digested spent wash from distilleries.
Inducible periplasmic chromate reducing activity in Pseudomonas aeruginosa isolated from a leather tannery effluent
(2001) A. Ganguli; A.K. Tripathi
A chromate tolerant strain of Pseudomonas aeruginosa isolated from the effluent of a tannery showed significant enzymatic activity of chromate reduction. Cells grown in chromate-supplemented medium reduced 8 μg chromate/mg protein/h in the presence of NADH/NADPH. The chromate reducing activity was inducible as cells pregrown in chromate showed higher chromate reduction. In contrast, the periplasmic fraction of cells grown in chromate reduced 75% chromate in 4 h and the spheroplast fraction failed to do so, indicating that chromate reductase may be located in the periplasm. The presence of a 30 kDa protein in the periplasmic extracts of cells grown in the presence of chromate, but its absence of the protein in cells grown without chromate, points out a possible role of this protein in chromate reduction.
Isolation and characterization of Azospirillum lipoferum locus that complements Rhizobium meliloti dctA and dctB mutations
(Canadian Science Publishing, 1996) A.K. Tripathi; B.M. Mishra
A DNA probe containing the structural gene for dicarboxylate transport (dct A) of Rhizobium meliloti hybridized strongly with the fragments of Azospirillum lipoferum genomic DNA. A genomic library of A. lipoferum was screened for the dct A gene by complementation of a dct A mutant of Rhizobium meliloti. A recombinant cosmid, p37D, capable of restoring growth of the dct A mutant on dicarboxylates was isolated and found to hybridize to the dctA probe. The ability of p37D to complement the dct B mutant of R. meloliti indicated that dct A and dct B genes in A. lipoferum may be organized adjacent to each other.
Isolation and characterization of salinity resistant mutant of a nitrogen‐fixing cyanobacterium, Anabaena doliolum
(1991) D.V. Singh; A.K. Tripathi; H.D. Kumar
D.V. SINGH. A.K. TRIPATHI AND H.D. KUMAR. 1991. Sodium chloride, up to 20 mmol/l concentration, had a positive effect on acetylene reducing activity and photosynthetic oxygen evolution of a paddy field cyanobacterium, Anabaena doliolum. Beyond 20 mmol/l level of salinity adverse effects appeared. A mutant resistant to 200 mmol/l NaCl was isolated by nitrosoguanidine mutagenesis. The mutant, NaCl‐R200, showed about 20–25% more nitrogenase activity and photosynthetic oxygen evolution than the parent. Better capacity of nitrogen fixation and photosynthesis possibly could help the mutant in synthesis of osmotic stabilizer to resist the salinity stress. Copyright © 1991, Wiley Blackwell. All rights reserved
Isolation of a hydroxyproline-secreting pigment-deficient mutant of Nostoc sp. by metronidazole selection
(Kluwer Academic Publishers, 1985) H.D. Kumar; A.K. Tripathi
A pigment-deficient mutant of Nostoc sp. was induced by N-methyl-N′-nitro-N-nitrosoguanidine and selected in a medium containing metronidazole. It formed chains of heterocysts, grew more slowly than the control, and excreted hydroxyproline into the medium, imparting a pinkish-brown colour to the cultures. © 1985 Oxford University Press.