scholarly journals Development of a method for improving stability method of applying digital watermarks to digital images

2021 ◽  
Vol 3 (2 (111)) ◽  
pp. 45-56
Author(s):  
Oleksandr Makoveichuk ◽  
Igor Ruban ◽  
Nataliia Bolohova ◽  
Andriy Kovalenko ◽  
Vitalii Martovytskyi ◽  
...  
Keyword(s):  
Wavelet Transforms ◽  
Digital Images ◽  
Digital Watermark ◽  
Image Rotation ◽  
Statistical Indicator ◽  
A Cell ◽  
Digital Watermarks ◽  
Statistical Mode ◽  
The Stability ◽  
Affine Type

A technique for increasing the stability of methods for applying digital watermark into digital images is presented. A technique for increasing the stability of methods for applying digital watermarks into digital images, based on pseudo-holographic coding and additional filtering of a digital watermark, has been developed. The technique described in this work using pseudo-holographic coding of digital watermarks is effective for all types of attacks that were considered, except for image rotation. The paper presents a statistical indicator for assessing the stability of methods for applying digital watermarks. The indicator makes it possible to comprehensively assess the resistance of the method to a certain number of attacks. An experimental study was carried out according to the proposed method. This technique is most effective when part of the image is lost. When pre-filtering a digital watermark, the most effective is the third filtering method, which is averaging over a cell with subsequent binarization. The least efficient is the first method, which is binarization and finding the statistical mode over the cell. For an affine type attack, which is an image rotation, this technique is effective only when the rotation is compensated. To estimate the rotation angle, an affine transformation matrix is found, which is obtained from a consistent set of corresponding ORB-descriptors. Using this method allows to accurately extract a digital watermark for the entire range of angles. A comprehensive assessment of the methodology for increasing the stability of the method of applying a digital watermark based on Wavelet transforms has shown that this method is 20 % better at counteracting various types of attacks

scholarly journals Digital Watermarks with Adaptive Information Ring Width in the Issue of Hidden Transmission of a Control Signal in the Multi-Target Robotic System

2020 ◽  
Vol 24 (2) ◽  
pp. 136-152
Author(s):  
O. O. Shumskaya ◽  
A. О. Iskhakova
Keyword(s):  
Ring Width ◽  
Digital Watermark ◽  
Robotic System ◽  
Control Signal ◽  
Image Rotation ◽  
Control Signals ◽  
Multi Agent ◽  
Digital Watermarks ◽  
Transmitted Signal ◽  
Hidden Data

Purpose of research. The article is devoted to the issue of ensuring the safe transmission of control signals between the elements of a multi-agent robotic system. The purpose of the work is to provide hidden data transmission with the possibility of unambiguous extraction of control signals.Methods. To solve the task set, an algorithm based on the methods of digital watermarks and digital steganography was proposed. The method of forming a digital watermark in the form of a ring with symmetry allows not only ensuring maximum imperceptibility of embedding (insignificant distortion of the container during concealment), but also to protect the transmitted signal from such complex distortions as image rotation. The steganographic concealment method allows regulating the intensity of embedding using the force factor; it is computationally simple and straightforward. The proposed approach to identifying and understanding the transmitted signal differs from modern methods of cryptography and steganalysis in that it does not require 100% correct signal extraction. After several modifications, the method allows minimizing the time spent on formation (adaptive width of the ring with signal bits) and embedding of a digital watermark (minimization of the processed area of the container for embedding).Results. The proposed approach makes it possible to transmit control signals in a hidden way within the framework of the transmission of digital objects; the conducted experiments have shown that the control signal is unambiguously understood even with such distortions as a decrease or increase in contrast or brightness, image rotation, and compression.Conclusion. Application of the proposed technique for transmitting control signals in a multi-agent robotic system will male it possible to receive the necessary information timely and safe, with a minimum probability of loss.

Using FRET to Measure the Time it Takes for a Cell to Destroy a Virus

2019 ◽  
Author(s):  
Candace E. Benjamin ◽  
Zhuo Chen ◽  
Olivia Brohlin ◽  
Hamilton Lee ◽  
Stefanie Boyd ◽  
...  
Keyword(s):  
Cellular Uptake ◽  
Rhodamine B ◽  
Virus Like Particle ◽  
A Cell ◽  
Viral Nanoparticles ◽  
The Stability ◽  
Open Question ◽  
Viral Surface ◽  
Fret Pair

<div><div><div><p>The emergence of viral nanotechnology over the preceding two decades has created a number of intellectually captivating possible translational applications; however, the in vitro fate of the viral nanoparticles in cells remains an open question. Herein, we investigate the stability and lifetime of virus-like particle (VLP) Qβ - a representative and popular VLP for several applications - following cellular uptake. By exploiting the available functional handles on the viral surface, we have orthogonally installed the known FRET pair, FITC and Rhodamine B, to gain insight of the particle’s behavior in vitro. Based on these data, we believe VLPs undergo aggregation in addition to the anticipated proteolysis within a few hours of cellular uptake.</p></div></div></div>

scholarly journals armadillo, bazooka, and stardust are critical for early stages in formation of the zonula adherens and maintenance of the polarized blastoderm epithelium in Drosophila.

1996 ◽  
Vol 134 (1) ◽  
pp. 149-163 ◽  
Author(s):  
H A Müller ◽  
E Wieschaus
Keyword(s):  
Plasma Membranes ◽  
Basolateral Membrane ◽  
Cell Sheet ◽  
Cell Monolayer ◽  
Test System ◽  
Sem Analysis ◽  
Drosophila Embryo ◽  
Early Stages ◽  
A Cell ◽  
The Stability

Cellularization of the Drosophila embryo results in the formation of a cell monolayer with many characteristics of a polarized epithelium. We have used antibodies specific to cellular junctions and nascent plasma membranes to study the formation of the zonula adherens (ZA) in relation to the establishment of basolateral membrane polarity. The same approach was then used as a test system to identify X-linked zygotically active genes required for ZA formation. We show that ZA formation begins during cellularization and that the basolateral membrane domain is established at mid-gastrulation. By creating deficiencies for defined regions of the X chromosome, we have identified genes that are required for the formation of the ZA and the generation of basolateral membrane polarity. We show that embryos mutant for both stardust (sdt) and bazooka (baz) fail to form a ZA. In addition to the failure to establish the ZA, the formation of the monolayered epithelium is disrupted after cellularization, resulting in formation of a multilayered cell sheet by mid-gastrulation. SEM analysis of mutant embryos revealed a conversion of cells exhibiting epithelial characteristics into cells exhibiting mesenchymal characteristics. To investigate how mutations that affect an integral component of the ZA itself influence ZA formation, we examined embryos with reduced maternal and zygotic supply of wild-type Arm protein. These embryos, like embryos mutant for both sdt and baz, exhibit an early disruption of ZA formation. These results suggest that early stages in the assembly of the ZA are critical for the stability of the polarized blastoderm epithelium.

scholarly journals Isolation and Characterization of Point Mutations in Mismatch Repair Genes That Destabilize Microsatellites in Yeast

2001 ◽  
Vol 21 (23) ◽  
pp. 8157-8167 ◽  
Author(s):  
Elaine Ayres Sia ◽  
Margaret Dominska ◽  
Lela Stefanovic ◽  
Thomas D. Petes
Keyword(s):  
Mismatch Repair ◽  
Dna Sequences ◽  
Point Mutations ◽  
Mismatch Repair Genes ◽  
Isolation And Characterization ◽  
Dna Mismatches ◽  
A Cell ◽  
The Stability ◽  
Yeast Mutants ◽  
Repair Genes

ABSTRACT The stability of simple repetitive DNA sequences (microsatellites) is a sensitive indicator of the ability of a cell to repair DNA mismatches. In a genetic screen for yeast mutants with elevated microsatellite instability, we identified strains containing point mutations in the yeast mismatch repair genes, MSH2,MSH3, MLH1, and PMS1. Some of these mutations conferred phenotypes significantly different from those of null mutations in these genes. One semidominant MSH2mutation was identified. Finally we showed that strains heterozygous for null mutations of mismatch repair genes in diploid strains in yeast confer subtle defects in the repair of small DNA loops.

scholarly journals Killing by Degradation: Regulation of Apoptosis by the Ubiquitin-Proteasome-System

Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3465
Author(s):  
Ruqaia Abbas ◽  
Sarit Larisch
Keyword(s):  
Apoptotic Cell ◽  
Ubiquitin Proteasome System ◽  
Cancer Therapies ◽  
E3 Ligases ◽  
Ubiquitin Proteasome ◽  
A Cell ◽  
Positive And Negative Feedback ◽  
Apoptotic Proteins ◽  
The Stability ◽  
Cell Suicide

Apoptosis is a cell suicide process that is essential for development, tissue homeostasis and human health. Impaired apoptosis is associated with a variety of human diseases, including neurodegenerative disorders, autoimmunity and cancer. As the levels of pro- and anti-apoptotic proteins can determine the life or death of cells, tight regulation of these proteins is critical. The ubiquitin proteasome system (UPS) is essential for maintaining protein turnover, which can either trigger or inhibit apoptosis. In this review, we will describe the E3 ligases that regulate the levels of pro- and anti-apoptotic proteins and assisting proteins that regulate the levels of these E3 ligases. We will provide examples of apoptotic cell death modulations using the UPS, determined by positive and negative feedback loop reactions. Specifically, we will review how the stability of p53, Bcl-2 family members and IAPs (Inhibitor of Apoptosis proteins) are regulated upon initiation of apoptosis. As increased levels of oncogenes and decreased levels of tumor suppressor proteins can promote tumorigenesis, targeting these pathways offers opportunities to develop novel anti-cancer therapies, which act by recruiting the UPS for the effective and selective killing of cancer cells.

scholarly journals Mobile and Intelligent Sensing for Video Watermarking Using Spectral Centroid and Haar Wavelet Transformation on High Performace Computing

2021 ◽  
Author(s):  
Venkatesh S ◽  
Saravanakumar R ◽  
SureshKumar M ◽  
sivakumar B ◽  
veeramakali T
Keyword(s):  
Wavelet Transform ◽  
Image Watermarking ◽  
Digital Watermark ◽  
Dft Method ◽  
3D Models ◽  
Haar Wavelet ◽  
Video Watermarking ◽  
Haar Wavelet Transform ◽  
Spectral Centroid ◽  
Digital Watermarks

Abstract Some technologies are technologically advanced to provide security from illegal copying. Two complementary methods are encryption and watermarking. Encryption safeguards the information throughout the communication from the sender to the receiver. The data might present a distorted image after receipt and subsequent decryption. Watermarking complements encryption through embedding data openly into the image. Therefore, the watermark continuously remains existing in the data. A digital watermark is a category of indication secretly entrenched in a noise-tolerant signal similar to audio or else image information. It is indeed applied to distinguish copyright possession of such signal. Computer-aided hiding of the given digitized information in a carrier is known as watermarking. Digital watermarks possibly will be employed to validate the authenticity or integrity of a carrier signal or to determine source uniqueness. It is evidently applied for determining copyright contraventions and aimed at banknote verification. Analogous to traditional watermarks, digital watermarks are unique only beneath certain conditions. Once a digital watermark varies a carrier in a manner that it turns out to be noticeable, formerly it is of no use. The media will be visible by traditional watermarks (similar to images or else video) but the signal might be pictures, video, audio, texts or 3D models in digital watermarking. A signal can transmit some different watermarks at the equivalent time. Image watermarking is achieved in this study using two methods known as Hidden Markov Tree–Contourlet Wavelet Transform (HMT-CWT) and Haar wavelet transform – Discrete Fourier transform (HWT-DFT). In the next HWT-DFT method, a video is given as an input and it is split into two halves (audio and image). The audio is de-watermarked through Spectral Centroid Wavelet Transform and enhanced by utilizing Firefly procedure. The images is handled through HWT in addition to DFT. Then the output watermarked images and audio combined together to form a watermarked video. The obtained video is de-watermarked to produce the original copy of the video. The process of getting back the original copy by removing the watermark from the video is called as de-watermarking.

scholarly journals Cosmc-dependent mucin-type O-linked glycosylation is essential for podocyte function

2020 ◽  
Vol 318 (2) ◽  
pp. F518-F530
Author(s):  
Brian R. Stotter ◽  
Brianna E. Talbot ◽  
Diane E. Capen ◽  
Nadine Artelt ◽  
Junwei Zeng ◽  
...  
Keyword(s):  
Renal Failure ◽  
Glomerular Sclerosis ◽  
Tn Antigen ◽  
Foot Process Effacement ◽  
Hemizygous Male ◽  
Podocyte Loss ◽  
A Cell ◽  
Foot Process ◽  
Matrix Organization ◽  
The Stability

Mucin-type O-linked glycosylation, a posttranslational modification affecting the stability and biophysical characteristics of proteins, requires C1GalT1 (T synthase) and its obligate, X-linked chaperone Cosmc. Hypomorphic C1GalT1 mutations cause renal failure via not yet established mechanisms. We hypothesize that impaired Cosmc-dependent O-glycosylation in podocytes is sufficient to cause disease. Podocyte-specific Cosmc knockout mice were generated and phenotyped to test this hypothesis. Female heterozygous mice displaying mosaic inactivation of Cosmc in podocytes due to random X-linked inactivation were also examined. Mice with podocyte-specific Cosmc deletion develop profound albuminuria, foot process effacement, glomerular sclerosis, progressive renal failure, and impaired survival. Glomerular transcriptome analysis reveals early changes in cell adhesion, extracellular matrix organization, and chemokine-mediated signaling pathways, coupled with podocyte loss. Expression of the O-glycoprotein podoplanin was lost, while Tn antigen, representing immature O-glycans, was most abundantly found on podocalyxin. In contrast to hemizygous male and homozygous female animals, heterozygous female mosaic animals developed only mild albuminuria, focal foot process effacement, and nonprogressive kidney disease. Ultrastructurally, Cosmc-deficient podocytes formed Tn antigen-positive foot processes interdigitating with those of normal podocytes but not with other Cosmc-deficient cells. This suggests a cell nonautonomous mechanism for mucin-type O-glycoproteins in maintaining podocyte function. In summary, our findings demonstrated an essential and likely cell nonautonomous role for mucin-type O-glycosylation for podocyte function.

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