Origins and minimization of intermodulation distortion in a pseudo-differential CMOS beamforming receiver

Analog Integrated Circuits and Signal Processing - This paper studies how nonlinear distortion is generated in the combination of an inverter-based low-noise amplifier and a passive mixer. The...     

Multi-Scale Attention-Based Deep Neural Network for Brain Disease Diagnosis

Whole brain functional connectivity (FC) patterns obtained from resting-state functional magnetic resonance imaging (rs-fMRI) have been widely used in the diagnosis of brain disorders such as autism spectrum disorder (ASD). Recently, an increasing number of studies have focused on employing deep learning techniques to analyze FC patterns for brain disease classification. However, the high dimensionality of the FC features and the interpretation of deep learning results are issues that need to be addressed in the FC-based brain disease classification. In this paper, we proposed a multi-scale attention-based deep neural network (MSA-DNN) model to classify FC patterns for the ASD diagnosis. The model was implemented by adding a flexible multi-scale attention (MSA) module to the auto-encoder based backbone DNN, which can extract multi-scale features of the FC patterns and change the level of attention for different FCs by continuous learning. Our model will reinforce the weights of important FC features while suppress the unimportant FCs to ensure the sparsity of the model weights and enhance the model interpretability. We performed systematic experiments on the large multi-sites ASD dataset with both ten-fold and leave-one-site-out cross-validations. Results showed that our model outperformed classical methods in brain disease classification and revealed robust inter-site prediction performance. We also localized important FC features and brain regions associated with ASD classification. Overall, our study further promotes the biomarker detection and computer-aided classification for ASD diagnosis, and the proposed MSA module is flexible and easy to implement in other classification networks.     

Synthesis,Characterization, Antibacterial Properties,and In Vitro Studies of Selenium and Strontium Co-Substituted Hydroxyapatite

In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO₃²⁻) in HA, strontium (Sr²⁺) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications.     

Functional Analysis of Autophagy-Related Gene ATG12 in Potato Dry Rot Fungus Fusarium oxysporum

Autophagy is an intracellular process in all eukaryotes which is responsible for the degradation of cytoplasmic constituents, recycling of organelles, and recycling of proteins. It is an important cellular process responsible for the effective virulence of several pathogenic plant fungal strains, having critical impacts on important crop plants including potatoes. However, the detailed physiological mechanisms of autophagy involved in the infection biology of soil-borne pathogens in the potato crop needs to be investigated further. In this study, the autophagy-related gene, FoATG12, in potato dry rot fungus Fusarium oxysporum was investigated by means of target gene replacement and overexpression. The deletion mutant ∆FoATG12 showed reduction in conidial formation and exhibited impaired aerial hyphae. The FoATG12 affected the expression of genes involved in pathogenicity and vegetative growth, as well as on morphology features of the colony under stressors. It was found that the disease symptoms were delayed upon being inoculated by the deletion mutant of FoATG12 compared to the wild-type (WT) and overexpression (OE), while the deletion mutant showed the disease symptoms on tomato plants. The results confirmed the significant role of the autophagy-related ATG12 gene in the production of aerial hyphae and the effective virulence of F. oxysporum in the potato crop. The current findings provid an enhanced gene-level understanding of the autophagy-related virulence of F. oxysporum, which could be helpful in pathogen control research and could have vital impacts on the potato crop.     

Water sorption studies on ZnSO4-zeolite composite as potential thermochemical heat storage materials

ZnSO₄·7H₂O is modified by impregnation method with zeolite matrices (13X-zeolite and LTA-zeolite) to improve its hydration performance. Water sorption ability of composites was carried out in a constant temperature and humidity environment. Composite of ZnSO₄/13X-zeolite showed highest water sorption (0.26 g/g) at 75% relative humidity under 45°C air temperature, which is double than pure ZnSO₄·7H₂O. This is due to larger surface area (491 m² g^-1) and pore volume (0.31 cm³). Furthermore, both hydration rate and adsorption mass depends on relative humidity and hydration temperature. However, if the air temperature and the relative humidity are higher than 45°C and 75% RH, the hydration ability of the composite material is significantly reduced. Besides, X-ray measurements of composite (ZnSO₄/13X) revealed that sorption/desorption process, crystallinity and phase of partially hydrated ZnSO₄ remain the same, which enhance the adsorption mass and enthalpy during the hydration process.     

Structural tailoring of molybdenum disulfide by argon plasma for efficient electrocatalysis performance

This article describes the synthesis of molybdenum disulfide (MoS₂) nanowires using chemical vapor deposition (CVD) method. The MoS₂-nanowires converts into micro-flake structures with the help of argon (Ar) plasma for the better hydrogen evolution reaction (HER) activity. The MoS₂-nanowires treated by post-Ar plasma at different time of intervals (20 seconds, 40 seconds, 60 seconds, and 3 minutes). The plasma treatment significantly tailored the structure of pristine MoS₂-nanowires due to which additional active sites were produced at the surface of treated MoS₂. A notable HER activity were achieved by plasma-treated MoS₂. To boost the HER activity up to next level, visible light was used at the time of electrocatalysis which enhanced the electrocatalytic activity almost double, which is evident by the low overpotential (190 mV) at current density of 10 mAcm⁻².     

Optimization of lipase activity under various chemo-physical conditions for hydrolysis of polyester fabric using multiple statistical approaches

Abstract

Polyester is known to be one of the most abundantly used fabrics. However, its surface is hydrophobic which restricts its wide acceptability and efficient processability. Therefore, many approaches have been adopted to overcome this shortcoming. This study dealt with the optimization of lipase activity under various chemo-physical conditions for hydrolysis of polyester fabric using statistical approaches. The study undertakes the effect of pH, temperature and surfactant type on Aspergillus niger lipase activity using Taguchi L₉ orthogonal array. Afterward, polyester was hydrolyzed under optimized conditions using central composite approach. It was found that lipase activity was higher at acidic pH and 50?°C with nonionic surfactant (Tween 80). The hydrolysis of polyester was carried out by varying lipase and non-ionic surfactant concentrations, and by changing the process time on a lab scale launder-o-meter. The significance of each input variable, squared and interaction terms on hydrolytic activity, weight loss, tensile strength and absorbency time was determined. Response optimizer was drawn to predict the effect of each input factor on output factor during hydrolysis of polyester which can be very beneficial for industrial processing.     

Insight into hydrogels

The development and introduction of injectable biomaterials and the identification of methods through which materials may form in situ are currently the topics of interest in materials science, specifically in the field of biomaterials. Over the last few decades, hydrogels which refers to the swellable polymeric matrices have gained wide attention due to their excellent characteristics such as swelling in different media, pH and temperature sensitivity, and sensitivity to other stimuli. Nowadays, injectable hydrogels have widely been studied due to their excellent insitu gelation at body temperature. These injectable insitu gels serve as depot system which ensures the local and systemic drug and gene delivery. These insitu gels also protect the proteins and peptide drugs invivo from environmental effect. The current review is made to report latest extensive literature regarding hydrogels, their classification, synthesis methods, structure of hydrogel network, methods of crosslinking, environment-sensitive hydrogel system, drug loading, and release, hydrogels as biosensors and applications of hydrogels.