Improved digital watermarking schemes using DCT and neural techniques

The present thesis investigates the copyright protection by utilizing the digital watermarking of images. The basic spatial domain technique DCT based frequency based technique were studied and simulated. Most recently used Neural Network based DCT Scheme is also studied and simulated. The earlier used Back Propagation Network (BPN) is replaced by Radial Basis Function Neural Network (RBFNN) in the proposed scheme to improve the robustness and overall computation requirements. Since RBFNN requires less number of weights during training, the memory requirement is also less as compared to BPN. Keywords : Digital Watermarking, Back Propagation Network (BPN), Hash Function, Radial Basis Function Neural Network (RBFNN), and Discrete Cosine Transform (DCT). Watermarking can be considered as a special technique of steganography where one message is embedded in another and the two messages are related to each other in some way. The most common examples of watermarking are the presence of specific patterns in currency notes, which are visible only when the note is held to light, and logos in the background of printed text documents. The watermarking techniques prevent forgery and unauthorized replication of physical objects. In digital watermarking a low-energy signal is imperceptibly embedded in another signal. The low-energy signal is called the watermark and it depicts some metadata, like security or rights information about the main signal. The main signal in which the watermark is embedded is referred to as the cover signal since it covers the watermark. In recent years the ease with which perfect copies can be made has lead large-scale unauthorized copying, which is a great concern to the music, film, book and software publishing industries. Because of this concern over copyright issues, a number of technologies are being developed to protect against illegal copying. One of these technologies is the use of digital watermarks. Watermarking embeds an ownership signal directly into the data. In this way, the signal is always present with the data. Analysis Digital watermarking techniques were implemented in the frequency domain using Discrete Cosine Transform (DCT). The DCT transforms a signal or image from the spatial domain to the frequency domain. Also digital watermarking was implemented using Neural Networks such as: 1. Back Propagation Network (BPN) 2. Radial Basis Function Neural Network (RBFNN) Digital watermarking using RBFNN was proposed which improves both security and robustness of the image. It is based on the Cover’s theorem which states that nonlinearly separable patterns can be separated linearly if the pattern is cast nonlinearly into a higher dimensional space. RBFNN contains an input layer, a hidden layer with nonlinear activation functions and an output layer with linear activation functions. Results The following results were obtained:- 1. The DCT based method is more robust than that of the LSB based method in the tested possible attacks. DCT method can achieve the following two goals: The first is that illegal users do not know the location of the embedded watermark in the image. The second is that a legal user can retrieve the embedded watermark from the altered image. 2. The RBFNN network is easier to train than the BPN network. The main advantage of the RBFNN over the BPN is the reduced computational cost in the training stage, while maintaining a good performance of approximation. Also less number of weights are required to be stored or less memory requirements for the verification and testing in a later stage

Are drug-drug interactions a real clinical concern?

Aim: Although drug-drug interactions (DDIs) cause major adverse drug reactions (ADRs) in patients under polypharmacy, the risk of some specific DDIs may be overrated in literature and different software. This study was conducted to determine the frequency and type of potential and clinically significant DDIs among inpatients admitted in a tertiary care hospital in South India. Materials and Methods: This longitudinal study was conducted for 30 days. Preformatted forms were used to collect data on the second day of admission. “Medscape Drug Interaction Checker” was used to evaluate and grade the DDIs. All the potential serious DDIs were intimated to the treating physicians and their responses in the prescriptions were noted. The same patients were followed up to evaluate the occurrence of any clinically significant DDIs. Results: A total of 763 drugs with 125 discrete types were prescribed in 155 patients with an average of 4.9 drugs per patient. One hundred and eight minor, 169 significant, and 24 serious potential DDIs were identified. Patient's age did not correlate, but number of drugs prescribed strongly correlated (P < 0.001) with the incidence of different types of DDIs. The prescription was modified in only 6 (25%) cases where potential serious DDIs were reported. Interestingly, no ADRs or impaired efficacy was observed due to the potential serious DDIs. Conclusion: There was a disparity between the potential and clinically relevant DDIs. Hence, clinical prudency is required before changing prescription due to potential DDIs reported by different software

Influence of Vitamin D Status and IL-10 Gene Promoter Polymorphism (rs1800871) on Plasma IL-10 Levels in Apparently Healthy Individuals from Southern India: A Cross-sectional Study

Introduction: Interleukin-10 (IL-10) is a major anti-inflammatory cytokine, which plays an important role in regulating inflammatory responses of the immune system. Changes in IL-10 level and its function can cause an imbalance in immune response, which can be associated with various disease conditions. Aim: To study the influence of vitamin D status and IL-10 gene promoter polymorphism (rs1800871) on circulating IL-10 cytokine levels in apparently healthy South Indian population. Materials and Methods: A cross-sectional study was conducted at the Department of Clinical Pharmacology, JIPMER, Puducherry, India from January 2016 to December 2017. Apparently healthy South Indian volunteers (N=101) of either sex, age more than 18 years, were recruited for the study, after obtaining written informed consent. Serum 25-hydroxy vitamin D and plasma IL-10 levels were measured by using Chemiluminescence and Enzyme Linked Immunosorbent Assay (ELISA), respectively. IL-10 rs1800871 genotyping was performed by Real Time-polymerase Chain Reaction (RT-PCR). Values were expressed as median, Inter quartile Range (IQR) and proportions were described as number with percentage. Results: The median serum vitamin D and plasma IL-10 levels observed among the study population were 18.21 ng/ mL IQR, 11.3-23.08 ng/mL) and 9.04pg/mL (IQR, 7.75, 11.34 pg/mL) respectively. The genotype and allele frequencies of rs1800871 were consistent with that of the African, South Asian population of 1000 genome project. Plasma IL-10 levels were not significantly different across genotypes (p-value=0.091), even though the median level among homozygous mutant (TT) volunteers was observed to be less (8.35 pg/mL vs 9.69 pg/mL, 9.83 pg/mL). The correlation between vitamin D and IL-10 levels was observed to be insignificant (p-value=0.143). Conclusion: The present study has reported the rs1800871 genotype frequency, circulating serum vitamin D levels and plasma IL-10 levels in the apparently healthy South Indian population. IL-10 cytokine levels were not significant across the different genotype and vitamin D status groups. No significant correlation was observed between the IL-10 and vitamin D levels among the sample studied

Atomoxetine Does Not Improve Complex Attention in Idiopathic Parkinson’s Disease Patients with Cognitive Deficits: A Meta-Analysis

Objectives. To evaluate the effects of atomoxetine on complex attention and other neurocognitive domains in idiopathic Parkinson’s disease (PD). Methods. Interventional trials reporting changes in complex attention and other neurocognitive functions (Diagnostic and Statistical Manual of Mental Disorders-5) following administration of atomoxetine for at least 8 weeks in adults with idiopathic PD were included. Effect sizes (Cohen’s d), the standardized mean difference in the scores of each cognitive domain, were compared using a random-effects model (MetaXL version 5.3). Results. Three studies were included in the final analysis. For a change in complex attention in PD with mild cognitive impairment (MCI), the estimated effect size was small and nonsignificant (0.16 (95% CI: −0.09, 0.42), n = 42). For changes in executive function, perceptual-motor function, language, social cognition, and learning and memory, the estimated effect sizes were small and medium, but nonsignificant. A deteriorative trend in executive function was observed after atomoxetine treatment in PD with MCI. For a change in global cognitive function in PD without MCI, the estimated effect size was large and significant. Conclusion. In idiopathic PD with MCI, atomoxetine does not improve complex attention. Also, a deteriorative trend in the executive function was noted