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In this article, a block-based adaptive contrast enhancement algorithm has been proposed, which uses a modified sigmoid function for the enhancement and features extraction of electron microscopic images. The algorithm is based on a modified sigmoid function that adapts according to the input microscopic image statistics. For feature extraction, the contrast of the image is very important and authentic property by which this article enhances the visual quality of the image. In this work, for better contrast enhancement of image, a block based on input value, combined with a modified sigmoid function that is used as contrast enhancer provides better EMF values for a smaller block size. It provides localized contrast enhancement effects adaptively which is not possible using other existing techniques. Simulation and experimental results demonstrate that the proposed technique gives better results compared to other existing techniques when applied to electron microscopic images. After the enhancement of microscopic images of actinomycetes, various important features are shown, like coil or spiral, long filament, spore and rod shape structures. The proposed algorithm works efficiently for different dark and bright microscopic images.

Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although effectors have been identified for a few sugar acid regulators, the mode of effector binding is unknown. Even in the overall FadR subfamily, there are limited details on effector-regulator interactions. Here, we identified the effector-binding cavity in Escherichia coli DgoR, a FadR subfamily transcriptional repressor of D-galactonate metabolism that employs D-galactonate as its effector. Using a genetic screen, we isolated several dgoR superrepressor alleles. Blind docking suggested eight amino acids corresponding to these alleles to form a part of the effector-binding cavity. In vivo and in vitro assays showed that these mutations compromise the inducibility of DgoR without affecting its oligomeric status or affinity for target DNA. Taking Bacillus subtilis GntR as a representative, we demonstrated that the effector-binding cavity is similar among FadR subfamily sugar acid regulators. Finally, a comparison of sugar acid regulators with other FadR members suggested conserved features of effector-regulator recognition within the FadR subfamily. Sugar acid metabolism is widely implicated in bacterial colonization and virulence. The present study sets the basis to investigate the influence of natural genetic variations in FadR subfamily regulators on their sensitivity to sugar acids and ultimately on host-bacterial interactions.

d-Galactonate, an aldonic sugar acid, is used as a carbon source by Escherichia coli, and the structural dgo genes involved in its metabolism have previously been investigated. Here, using genetic, biochemical and bioinformatics approaches, we present the first detailed molecular and functional insights into the regulation of d-galactonate metabolism in E. coli K-12 by the transcriptional regulator DgoR. We found that dgoR deletion accelerates the growth of E. coli in d-galactonate concomitant with the strong constitutive expression of dgo genes. In the dgo locus, sequence upstream of dgoR alone harbors the d-galactonate-inducible promoter that likely drives the expression of all dgo genes. DgoR exerts repression on the dgo operon by binding two inverted repeats overlapping the dgo promoter. Binding of d-galactonate induces a conformational change in DgoR to derepress the dgo operon. The findings from our work firmly place DgoR in the GntR family of transcriptional regulators: DgoR binds an operator sequence [5′-TTGTA(G/C)TACA(A/T)-3′] matching the signature of GntR family members that recognize inverted repeats [5′-(N)yGT(N)xAC(N)y-3′, where x and y indicate the number of nucleotides, which varies], and it shares critical protein-DNA contacts. We also identified features in DgoR that are otherwise less conserved in the GntR family. Recently, missense mutations in dgoR were recovered in a natural E. coli isolate adapted to the mammalian gut. Our results show these mutants to be DNA binding defective, emphasizing that mutations in the dgo-regulatory elements are selected in the host to allow simultaneous induction of dgo genes. The present study sets the basis to explore the regulation of dgo genes in additional enterobacterial strains where they have been implicated in host-bacterium interactions. IMPORTANCEd-Galactonate is a widely prevalent aldonic sugar acid. Despite the proposed significance of the d-galactonate metabolic pathway in the interaction of enteric bacteria with their hosts, there are no details on its regulation even in Escherichia coli, which has been known to utilize d-galactonate since the 1970s. Here, using multiple methodologies, we identified the promoter, operator, and effector of DgoR, the transcriptional repressor of d-galactonate metabolism in E. coli. We establish DgoR as a GntR family transcriptional regulator. Recently, a human urinary tract isolate of E. coli introduced in the mouse gut was found to accumulate missense mutations in dgoR. Our results show these mutants to be DNA binding defective, hence emphasizing the role of the d-galactonate metabolic pathway in bacterial colonization of the mammalian gut.

The domain of cloud computing has transformed from a niche domain to a ubiquitous one. Cloud computing basically means access to shared computing resources such as network, storage and, IT. over the internet on a pay-as-you-use basis. There are three major aspects related to cloud, namely. storage, load balancing, and security. With the ever-increasing quantity of data and organizations surpassing geographical boundaries, the acceptance of cloud has increased. We wish to contribute to this field whose relevance is growing by the day. Hence we have aimed to develop an efficient model for storing and retrieving files over cloud using a data-centric approach. As of now, most existing techniques distribute content over servers based on server parameters such as availability of the server and current load on server. However, statistics regarding the type of content over the internet and their percentages suggest that this information can be utilized to create a more efficient model of storage. In this paper, we have proposed an algorithm for management of files over cloud on basis of the extension or the type of file, wherein each server will be dedicated to a particular data content. These management of files promise a better access speed (upload and download) from the local machine to the cloud and vice versa.

d-Galactonate, an aldonic sugar acid, is used as a carbon source by Escherichia coli, and the structural dgo genes involved in its metabolism have previously been investigated. Here, using genetic, biochemical and bioinformatics approaches, we present the first detailed molecular and functional insights into the regulation of d-galactonate metabolism in E. coli K-12 by the transcriptional regulator DgoR. We found that dgoR deletion accelerates the growth of E. coli in d-galactonate concomitant with the strong constitutive expression of dgo genes. In the dgo locus, sequence upstream of dgoR alone harbors the d-galactonate-inducible promoter that likely drives the expression of all dgo genes. DgoR exerts repression on the dgo operon by binding two inverted repeats overlapping the dgo promoter. Binding of d-galactonate induces a conformational change in DgoR to derepress the dgo operon. The findings from our work firmly place DgoR in the GntR family of transcriptional regulators: DgoR binds an operator sequence [5′-TTGTA(G/C)TACA(A/T)-3′] matching the signature of GntR family members that recognize inverted repeats [5′-(N)(y)GT(N)(x)AC(N)(y)-3′, where x and y indicate the number of nucleotides, which varies], and it shares critical protein-DNA contacts. We also identified features in DgoR that are otherwise less conserved in the GntR family. Recently, missense mutations in dgoR were recovered in a natural E. coli isolate adapted to the mammalian gut. Our results show these mutants to be DNA binding defective, emphasizing that mutations in the dgo-regulatory elements are selected in the host to allow simultaneous induction of dgo genes. The present study sets the basis to explore the regulation of dgo genes in additional enterobacterial strains where they have been implicated in host-bacterium interactions. IMPORTANCE d-Galactonate is a widely prevalent aldonic sugar acid. Despite the proposed significance of the d-galactonate metabolic pathway in the interaction of enteric bacteria with their hosts, there are no details on its regulation even in Escherichia coli, which has been known to utilize d-galactonate since the 1970s. Here, using multiple methodologies, we identified the promoter, operator, and effector of DgoR, the transcriptional repressor of d-galactonate metabolism in E. coli. We establish DgoR as a GntR family transcriptional regulator. Recently, a human urinary tract isolate of E. coli introduced in the mouse gut was found to accumulate missense mutations in dgoR. Our results show these mutants to be DNA binding defective, hence emphasizing the role of the d-galactonate metabolic pathway in bacterial colonization of the mammalian gut.

Cloud Computing is the current trend and will be future era because of its advantages like pay per usage and on demand services. Load Balancing is a key aspect of Cloud Computing. It is the distribution of network or applications traffic across a number of servers. As the volume of data is increasing day by day the organizations will migrate from traditional computer system to the cloud based system. Since the processing of data is increasing on daily basis, balancing of load across the entire server is an important aspect. Some of the most commonly used existing load balancing algorithms are weighted least-connection, weighted round-robin, active clustering, and feedback-driven dynamic load balancing. They are classified as either static or dynamic. The existing methods are server-centric, i.e., while distributing load among servers, only server parameters (number of active connections, response time, geographic location, server capability etc.) are taken into consideration. However, statistics on the different types of content present on the internet, their percentage and usage suggest that it can be improved. We are proposing a dynamic load balancing algorithm which will assign load to the servers depending on the type of content it possesses.

To predict the mathematical isopleths model for the growth of fungal mycelium in building material. The mould fungal growth is one of the first signs of biological growth linked to relative humidity and temperature condition in buildings materials. The numerical growth model was based on several models are found in literature. Quantification of fungal growth in the model is based on mould index used in the experiments for visual inspection. This model consists of differential equations describe the growth rate of the fungal growth index in vary fluctuating conditions including the effect of exposure time, temperature, relative humidity and dryness. Up to now the mathematical isopleth model to assess the fungal mould growth which is based on steady boundary conditions. This study presented new results for mathematical isopleth of mould growth on the surface of building materials such as wood, cement, concrete. Key Words: Mould, building material, isopleths model and relative humidity.

A mathematical model for the growth of filamentous microorganisms has been tested by comparison of model predictions with data on growth of Streptomyces on building wood material. Growth of Streptomyces resulted in movement of filament classes to increasing the size, while shear forces produced mycelial fragments which entered the smallest size class, from which they grew to form further colonies on building surface materials. Quantification of Streptomyces growth in the model is based on the mould index used in the experiments for visual inspection. The model consists of differential equations describing the growth rate of the mould index in different fuctuating conditions including the effect of exposure time, temperature, relative humidity and dry periods. Temperature and humidity conditions favourable for mould growth are presented as a mathematical model. The modified model generated predictions which agreed closely with experimental data on biomass concentration, distribution, number of colonies and colonies radius during their growth on building wood material, thereby supporting the assumptions on which the model was based. The numerical values of the parameters included in the model are fitted for pine and spruce sapwood, but the functional form of the model can be reasoned to be valid also for other wood-based materials. Keywords : streptomycetes, mathematical model, building materials, humidity, temperature

Generally, old buildings and monuments are often affected by biodecay. An inventory of the existing microbial consortia which associated with the damage part of the buildings wall is not yet integral part of the restoration process. This stems from the lack of effective means for such stocktaking. Although, Actinomycetes, fungi and bacteria cause severe damage through mechanical process from the growth into wall and its grounding and through their metabolism. Physiological and molecular approach based techniques were used in the detection and identification of DNA sequences encoding rRNA to actinomycetes present on building wall. DNA from isolate was extracted and 194 basepair fragments of the 16S rDNA were amplified with cultured primers. The 16S rDNA fragments of uniform length obtained from the different species were separated according to their sequences difference by PCR. By the sequencing excised and reamplified individual DNA bands, characterized the phylogenetic tree of corresponding actinomycetes. Using this approach, we identified members of the genera of Streptomyces , Nocardia and Micromonospora . Key words: Actinomycetes, Nocardia, Micromonospora, Streptomyces

Background: Endometrial carcinoma is a common neoplasm associated with the female genital tract with considerable morbidity.Eendometrial hyperplasias have been widely regarded as precursor lesions. It is of importance to the pathologist to identify the subset of hyperplasias or the associated factor which could be a possible forerunner of malignancy. Phospho tensin gene (PTEN) has gained importance as one of the factors responsible. Aim: To determine the variability in PTEN expression patterns in different types of endometrial hyperplasias. Settings and Design: The study was undertaken on samples received at the Department of Pathology from 2005 to 2007. Materials and Methods: One hundred samples with 76 showing hyperplasias of different types formed the core study group with simple hyperplasia without atypia predominating. The rest belonged to the control groups. PTEN intensity and percentage positivity, variability in patterns of glandular and stromal expression, the number and type of PTEN null glands in different types of hyperplasia were evaluated. Statistical analyses used were Fisher's exact test based on Monte Carlo test and chi-square test. Results: Complex hyperplasia was associated with a reduction in number of strongly PTEN positive glands, with an increase in null glands, seen in clusters. Co-existing atypia was associated with the weakest staining and in fewer glands. Conclusions: PTEN expression in endometrial hyperplasias can be used as an early warning of heightened cancer risk and a potential target for preventive treatment. However, extensive research is needed along this line to conclusively establish its effectiveness.