Error estimators and their analysis for CG, Bi-CG and GMRES

We present an analysis of the uncertainty in the convergence of iterative linear solvers when using relative residue as a stopping criterion, and the resulting over/under computation for a given tolerance in error. This shows that error estimation is indispensable for efficient and accurate solution of moderate to high conditioned linear systems ($\kappa>100$), where $\kappa$ is the condition number of the matrix. An $\mathcal{O}(1)$ error estimator for iterations of the CG (Conjugate Gradient) algorithm was proposed more than two decades ago. Recently, an $\mathcal{O}(k^2)$ error estimator was described for the GMRES (Generalized Minimal Residual) algorithm which allows for non-symmetric linear systems as well, where $k$ is the iteration number. We suggest a minor modification in this GMRES error estimation for increased stability. In this work, we also propose an $\mathcal{O}(n)$ error estimator for A-norm and $l_{2}$ norm of the error vector in Bi-CG (Bi-Conjugate Gradient) algorithm. The robust performance of these estimates as a stopping criterion results in increased savings and accuracy in computation, as condition number and size of problems increase

The Role of RecX in Mycobacteria

Tuberculosis is a major global public health problem which causes millions of deaths every year. It is caused by the bacterium Mycobacterium tuberculosis, which survives and replicates within host macrophages, in which it has to overcome the effects of various DNA damaging agents in order to survive. In bacteria, the RecA protein regulates DNA-damage repair. RecA also plays a central role in regulation of the SOS response and homologous recombination. In Mycobacterium smegmatis and Mycobacterium tuberculosis, downstream of, overlapping and co-transcribed with recA is the recX gene. Using a recA-recX deletion mutant of M. smegmatis, it has been shown that the over expression of recA is toxic in the absence of recX, suggesting that RecX plays a regulatory role on RecA. This project is aimed at investigating the hypothesis that RecX plays a regulatory role in RecA function in Mycobacterium tuberculosis. Various in vivo and in vitro studies were carried out to test this hypothesis and characterise the nature of RecA regulation by RecX. To investigate their mode of interaction, the purified RecX protein was used in DNA mobility shift assays to look for interactions with the M. smegmatis and M. tuberculosis recA upstream regions. No interaction was observed, suggesting that RecX does not regulate recA expression at the transcriptional level. A positive interaction was found for RecA and RecX in a yeast two-hybrid study, demonstrating a post-translational mode of interaction and regulation. The in vitro studies included LexA cleavage and ATP hydrolysis studies. When activated RecA is incubated with LexA, it results in the RecA-mediated auto catalytic cleavage of LexA. When RecX was added with RecA, a clear inhibition in LexA cleavage was observed. All reactions promoted by RecA in vitro are dependent on its binding to single-stranded DNA in the presence of ATP to produce an active nucleoprotein filament. It was found in ATPase assays, that RecX inhibits RecA ATP hydrolysis activity. To investigate the function of RecX in vivo, an assay was carried out to determine whether recX promotes survival when expression of recA is induced by DNA damage. A recA-recX deletion mutant of M smegmatis complemented with M. smegmatis recA+recX showed a higher percentage survival following DNA damage than when complemented with recA alone. Using the same recA-recX deletion strain of M. smegmatis in a homologous recombination assay, it was found that there is an increase in the frequency of double crossover events in recA+recX strains when compared to ΔrecX strains. Further in vivo studies demonstrated that recX enhances the recovery of RecA levels following pulse DNA damage

A Survey on Image Encryption and Decryption using Blowfish & Watermarking

Internet means International Network. In the present era, to send and receive information, the internet is the main media. This information may be text, audio, graphics and video etc. There are many advantages of internet. Internet provides quickest data delivery services, security of data is major concern for all internet users. There is always a sense of insecurity amongst internet user after sending data or image until he gets an acknowledgment from the opposite side informing that they have received the data safely, that too without any manipulation in its content. The confidentiality, non-repudiation, validation, reliability, of the information (data or image) should be checked properly otherwise data manipulation can have big problem. We can get these objectives with cryptography which is simply the science of securing sensitive and confidential information as it is stored on media or transmitted through communication network paths. Here, images are considered with an aim to secure them during its storage and transmission. Blowfish Algorithm, a type of symmetric key cryptography is the best solution for this. The two processes, encryption and decryption together form the cryptographic process. For ensuring security, the images are encrypted by the sender before transmitting them and are decrypted by the receiver after receiving them so that only the sender and the intended person can see the content in the image. The blowfish algorithm is safe against unauthorized attack and runs faster than the popular accessible algorithms. For double protection, after the blowfish process, the encrypted image tends to go through a water marking process which is used to hide a secret or personal message to protect a products copyright or to demonstrate data integrity Watermarking is the process of embedding new data into image, audio or video. We perform watermarking on different types of images say JPEG, BMP etc. The anticipated work is designed and implemented using MATLAB. DOI: 10.17762/ijritcc2321-8169.150516

A Survey on Energy Efficient Routing In MANETs Using Multi-Objective Genetic Algorithm

Mobile ad hoc networks (MANET) are self-establishing network that contains short radio range and limited bandwidth and they do not have any specified infrastructure. The ad hoc network changes its topology suddenly. In such this type of situation, establishing correct and efficient routes from source to destination is an important design issue in mobile ad hoc networks and its challenging goal is to provide energy efficient routing protocol. For finding the shortest path between the sources to destination, the routing technique genetic algorithm (GA) plays an important role. Such type of routing technique will reduce in finding the route again and again when any failure occurs in the path. Hence, it will take less time in sending again the packet to the destination and therefore it results in increasing throughput in the Mobile Ad hoc Network. In this paper, we have discussed the routing protocols, its classifications, advantage and disadvantages of the routing protocols and taxonomy of energy efficient routing protocols in Mobile Ad hoc network. DOI: 10.17762/ijritcc2321-8169.160411

Hemimegalencephaly: Seizure outcome in an infant after hemispherectomy

Isolated hemimegalencephaly (iHME) is a rare form of congenital malformation of cortical development characterized by enlargement of all or part of one cerebral hemisphere. It typically presents with intractable seizures, developmental delay, contralateral hemiparesis, and hemianopia. We report a case of an 18-month-old girl who presented first with focal seizures at tenth day of life, with no other physical or behavioral abnormality. Initial EEG showed excessive sharp EEG transients more over the right hemisphere; repeated EEG showed spikes, polyspikes, sharps, and slow wave discharges predominately over the right hemisphere. MRI of the brain showed asymmetric enlargement of the right cerebral hemisphere, suggestive of hemimegalencephaly. Initial treatment with antiepileptic drugs (AEDs) was successful in controlling her seizures, but later on the seizures became intractable even on polytherapy of AEDs; finally, functional hemispherectomy was performed and she became seizure free. Identification of this and similar cases of iHME can help us to better understand this disorder and eventually to provide better treatment options for it

Kaluza–Klein gluon + jets associated production at the Large Hadron Collider

AbstractThe Kaluza–Klein excitations of gluons offer the exciting possibility of probing bulk Randall–Sundrum (RS) models. In these bulk models either a custodial symmetry or a deformation of the metric away from AdS is invoked in order to deal with electroweak precision tests. Addressing both these models, we suggest a new channel in which to study the production of KK-gluons (gKK): one where it is produced in association with one or more hard jets. The cross-section for the gKK + jets channel is significant because of several contributing sub-processes. In particular, the 1-jet and the 2-jet associated processes are important because at these orders in QCD the qg and the gg initial states respectively come into play. We have performed a hadron-level simulation of the signal and present strategies to effectively extract the signal from what could potentially be a huge background. We present results for the kinematic reach of the LHC Run-II for different gKK masses in bulk-RS models

Three siblings with Charcot-Marie-tooth Disease with no other family history

Charcot-Marie-Tooth (CMT) disease is one of the most common inherited disorders of the peripheral nervous system. Patients diagnosed with CMT disease have axonal degeneration which results in muscle wasting, sensory loss and weakness. These patients have a very characteristic walking gait and shape of hands, along with other changes. Despite many common visible changes, no singular common genetic mutation for this disease or its cure has been identified. Therefore more case series for this disease needs to be identified so that future studies increase our knowledge about this disease. Here, we present a case series of 3 out of 4 siblings who have been diagnosed with CMT disease. Based on their age, these siblings show the different developmental stages of this disease. More of such case series need to be identified and reported so that we can identify the true genetic cause of this disease and develop a definitive cure for it