Self-interference cancellation in underwater acoustic communications systems using orthogonal pilots in IBFD

This paper proposes a Self-interference (SI) cancellation system model of Underwater acoustic (UWA) communication for in-band full-duplex (IBFD) technology. The SI channel is separated from the Far channel by exploiting a concurrently orthogonal pilot channel estimation technique using two orthogonal frequency-division multiplexing (OFDM) blocks to establish orthogonality between them based on a unitary matrix. Compared to the half-duplex channel estimator, the mean squared error (MSE) and the bit error rate (BER) provided strong evidence for the efficiency of the proposed SI cancellation. Since full-duplex systems are more efficient than half-duplex ones, the proposed approach might be seen as a viable option for them. The proposed method proved effective when used with a fixed full-duplex (FD) position and FD shifting of up to 4°. Different channel lengths and distances are adopted to evaluate the proposed method. Initial findings indicate that MSE for the SI channel minimum mean-square error (MMSE) estimator at 20 dB is 0.118 · 10−3, for fixed FD. In addition, this paper presents a geometry channel model for the Far channel in the IBFD underwater communication system that describes the propagation delay of the multipath reflection. The simulation results for the multipath propagation delay spread are similar to the traditional results, with the delay spread of the suggested model reaching (79 ms), which is close to the Bellhop simulator result (78 ms)

Atypical Neuroimaging Manifestations of Linear Scleroderma “en coup de sabre”

How to Cite This Article: Allmendinger AM, Ricci JA, Desai NS, Viswanadhan N, Rodriguez D. Atypical Neuroimaging Manifestations of Linear Scleroderma “en coup de sabre”. Iran J Child Neurol. Summer 2015;9(3):62-68.AbstractLinear scleroderma “en coup de sabre” is a subset of localized sclerodermawith band-like sclerotic lesions typically involving the fronto-parietal regionsof the scalp. Patients often present with neurologic symptoms. On imaging,patients may have lesions in the cerebrum ipsilateral to the scalp abnormality.Infratentorial lesions and other lesions not closely associated with the overlyingscalp abnormality, such as those found in the cerebellum, have been reported,but are extremely uncommon. We present a case of an 8-year-old boy with a left fronto-parietal “en coup de sabre” scalp lesion and describe the neuroimaging findings of a progressively enlarging left cerebellar lesion discovered incidentally on routine magnetic resonance imaging. Interestingly, the patient had no neurologic symptoms given the size of the mass identified

Photo-electrochemical Hydrogen Sulfide Splitting using SnIV-doped Hematite Photo-anodes

© 2016 The Authors. Published by Elsevier B.V.Spray-pyrolysed SnIV-doped α-Fe2O3 photo-anodes were used for photo-assisted splitting of HS- ions in alkaline aqueous solutions, producing polysulfide (Sn2 -) ions together with hydrogen at the cathode. Subsequent aerial oxidation of polysulfide could be used to produce elemental sulfur. At an applied electrode potential of 1.07 V (RHE) and an irradiance of 5.6 kW m- 2, stable photocurrents of ca. 11 A m- 2 (2 × 10- 3 A W- 1) were recorded over 75 h, polysulfide concentrations increasing linearly with time. Despite being predicted thermodynamically to form iron sulfide(s) in sulfide solutions, such photo-anodes appeared to be stable. In comparison with conventional water splitting under alkaline conditions, the coupled processes of hydrogen sulfide ion oxidation and water reduction had a lower energy requirement

Neuropharmacological evaluation of hormones in mice and insilico analysis of melatonin and somatostatin receptors

Spatial learning and memory consolidation are important aspects of human cognition. The test for motor co-ordination in mice is to characterize the motor phenotype of animals and also in relation to human beings. It is among the most fundamental aspects of everyday life as each physiological process that must be performed in order to achieve movement. In this study, depressive effect and effect on learning and memory of the two hormones, melatonin and somatostatin on animals was evaluated using the loco-motor activity test, rotarod and rectangular maze. The effect of Melatonin and Octreotide acetate alone and in combination with each other were estimated in Swiss albino mice. Melatonin was administered dose dependently and time dependently. Octreotide acetate was administered dose dependently. We compared the combined effect of these hormones for motor co-ordination, loco-motor activity and for the memory and learning behavior of animals. As per the present study, we found significant changes in the motor co-ordination, learning, and memory and depressive effect in animals and there was potentiated depression and attenuated learning and memory when the hormones were used in combination. In-silco analysis was conducted using Patchdock software and molecular docking of the ligands to their respective receptors conducted

Certified Zeroth-order Black-Box Defense with Robust UNet Denoiser

Certified defense methods against adversarial perturbations have been recently investigated in the black-box setting with a zeroth-order (ZO) perspective. However, these methods suffer from high model variance with low performance on high-dimensional datasets due to the ineffective design of the denoiser and are limited in their utilization of ZO techniques. To this end, we propose a certified ZO preprocessing technique for removing adversarial perturbations from the attacked image in the black-box setting using only model queries. We propose a robust UNet denoiser (RDUNet) that ensures the robustness of black-box models trained on high-dimensional datasets. We propose a novel black-box denoised smoothing (DS) defense mechanism, ZO-RUDS, by prepending our RDUNet to the black-box model, ensuring black-box defense. We further propose ZO-AE-RUDS in which RDUNet followed by autoencoder (AE) is prepended to the black-box model. We perform extensive experiments on four classification datasets, CIFAR-10, CIFAR-10, Tiny Imagenet, STL-10, and the MNIST dataset for image reconstruction tasks. Our proposed defense methods ZO-RUDS and ZO-AE-RUDS beat SOTA with a huge margin of $35\%$ and $9\%$, for low dimensional (CIFAR-10) and with a margin of $20.61\%$ and $23.51\%$ for high-dimensional (STL-10) datasets, respectively

Modeling the Geometry of an Underwater Channel for Acoustic Communication, Journal of Telecommunications and Information Technology, 2022, nr 4

The achievement of efficient data transmissions via underwater acoustic channels, while dealing with large data packets and real-time data fed by underwater sensors, requires a~high data rate. However, diffraction, refraction, and reflection phenomena, as well as phase and amplitude variations, are common problems experienced in underwater acoustic (UWA) channels. These factors make it difficult to achieve high-speed and long-range underwater acoustic communications. Due to multipath interference caused by surface and ocean floor reflections, the process of modeling acoustic channels under the water's surface is of key importance. This work proposes a~simple geometry-based channel model for underwater communication. The impact that varying numbers of reflections, low water depth values, and distances between the transmitter and the receiver exert on channel impulse response and transmission loss is examined. The high degree of similarity between numerical simulations and actual results demonstrates that the proposed model is suitable for describing shallow underwater acoustic communication environments

Influence de la fertilisation azotée sur l'activité nitrate réductase et sur les teneurs en nitrates des feuilles et racines principales de la betterave à sucre (Beta vulgaris Var. Maghribel)

L'activité nitrate réductase (ANR) a été mesurée dans les feuilles (limbes et pétioles) et dans les racines pivotantes (partie sous le collet, partie médiane et pointe de la racine principale) de la betterave à sucre cultivée en plein champ. L'ANR est toujours élevée dans les jeunes tissus racinaires ou foliaires. Elle se localise surtout au niveau du limbe. Au fur et à mesure que la plante se développe, l'ANR diminue dans les différents organes et surtout dans la racine; elle diminue au cours de la tubérisation pour s'annuler vers le 140ème jour après semis. L'évolution de cette ANR suit celle des teneurs en nitrates des différents organes. L'effet de l'azote sur l'ANR et sur les teneurs en nitrates est très hautement significatif

Usefulness of gene expression profiling of bronchoalveolar lavage cells in acute lung allograft rejection.

BackgroundChronic lung allograft dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Because effective therapies are lacking, early identification and mitigation of risk factors is a pragmatic approach to improve outcomes. Acute cellular rejection (ACR) is the most pervasive risk factor for CLAD, but diagnosis requires transbronchial biopsy, which carries risks. We hypothesized that gene expression in the bronchoalveolar lavage (BAL) cell pellet (CP) could replace biopsy and inform on mechanisms of CLAD.MethodsWe performed RNA sequencing on BAL CPs from 219 lung transplant recipients with A-grade ACR (n = 61), lymphocytic bronchiolitis (n = 58), infection (n = 41), or no rejection/infection (n = 59). Differential gene expression was based on absolute fold difference >2.0 and Benjamini-adjusted p-value ≤0.05. We used the Database for Annotation, Visualization and Integrated Discovery Bioinformatics Resource for pathway analyses. For classifier modeling, samples were randomly split into training (n = 154) and testing sets (n = 65). A logistic regression model using recursive feature elimination and 5-fold cross-validation was trained to optimize area under the curve (AUC).ResultsDifferential gene expression identified 72 genes. Enriched pathways included T-cell receptor signaling, natural killer cell-mediated cytotoxicity, and cytokine-cytokine receptor interaction. A 4-gene model (AUC = 0.72) and classification threshold defined in the training set exhibited fair performance in the testing set; accuracy was 76%, specificity 82%, and sensitivity 60%. In addition, classification as ACR was associated with worse CLAD-free survival (hazard ratio = 2.42; 95% confidence interval = 1.29-4.53).ConclusionsBAL CP gene expression during ACR is enriched for immune response pathways and shows promise as a diagnostic tool for ACR, especially ACR that is a precursor of CLAD

FracDetect: A novel algorithm for 3D fracture detection in digital fractured rocks

Fractures have a governing effect on the physical properties of fractured rocks, such as permeability. Accurate representation of 3D fractures is, therefore, required for precise analysis of digital fractured rocks. However, conventional segmentation methods fail to detect and label the fractures with aperture sizes near or below the resolution of 3D micro-computed tomographic (micro-CT) images, which are visible in the greyscale images, and where greyscale intensity convolution between different phases exists. In addition, conventional methods are highly subjective to user interpretation. Herein, a novel algorithm for the automatic detection of fractures from greyscale 3D micro-CT images is proposed. The algorithm involves a low-level early vision stage, which identifies potential fractures, followed by a high-level interpretative stage, which enforces planar continuity to reject false positives and more reliably extract planar fractures from digital rock images. A manually segmented fractured shale sample was used as the groundtruth, with which the efficacy of the algorithm in 3D fracture detection was validated. Following this, the proposed and conventional methods were applied to detect fractures in digital fractured coal and shale samples. Based on these analyses, the impact of fracture detection accuracy on the analysis of fractured rocks' physical properties was inferred

Evaluation and Improvement of Diesel Cut from Tawke Crude Oil Wells, Zakho

The straight run diesel cuts of crude oil from T-8 and T-16 Tawke well-Zakho have been examined (qualitative and quantitative). Physical properties such as (density, API, viscosity, cloud point, flash point, water content, sulfur content…. etc.) of this crude oil and diesel product have been measured according to the ASTM method. To improve chemical constituents of these crude oils and increasing the diesel distillation volume cuts by using three types of local clays, X-Ray fluorescence spectroscopy analysis of these clays have been done, a series experiments have been done at a different percentage of local clays and different time of reflux for Tawke wells T-8 and T-16 crude oil. These experiments were performed, in order to optimize the best clay and percentage, as well as finding the suitable reflux time to enhance the volume of the fraction at (200-320) °C. The figures have been plotted to find the optimum percentage weight for each clay, time of reflux, and temperatures. The change in chemical constitutes of these crude oils have been monitored by gas chromatography and tabulated in tables