MOF-Derived Cu@Cu2O Nanocatalyst for Oxygen Reduction Reaction and Cycloaddition Reaction

Research on the synthesis of nanomaterials using metal-organic frameworks (MOFs), which are characterized by multi-functionality and porosity, as precursors have been accomplished through various synthetic approaches. In this study, copper and copper oxide nanoparticles were fabricated within 30 min by a simple and rapid method involving the reduction of a copper(II)-containing MOF with sodium borohydride solution at room temperature. The obtained nanoparticles consist of a copper core and a copper oxide shell exhibited catalytic activity in the oxygen reduction reaction. The as-synthesized Cu@Cu2O core-shell nanocatalyst exhibited an enhanced limit current density as well as onset potential in the electrocatalytic oxygen reduction reaction (ORR). Moreover, the nanoparticles exhibited good catalytic activity in the Huisgen cycloaddition of various substituted azides and alkynes under mild reaction conditions

Multifunctional flax fibres based on the combined effect of silver and zinc oxide (Ag/ZnO) nanostructures

Cellulosic fibre-based smart materials exhibiting multiple capabilities are getting tremendous attention due to their wide application areas. In this work, multifunctional flax fabrics with piezoresistive response were developed through the combined functionalization with silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs). Biodegradable polyethylene glycol (PEG) was used to produce AgNPs, whereas ZnONPs were synthetized via a simple and low-cost method. Flax fabrics with and without NPs were characterized by Ground State Diffuse Reflectance (GSDR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), and Thermogravimetric analysis (TGA). After creating a conductive surface by flax functionalization with AgNPs, ZnONPs were synthetized onto these fabrics. The developed fibrous systems exhibited piezoresistive response and the sensor sensitivity increased with the use of higher ZnO precursor concentrations (0.4 M). Functionalized fabrics exhibited excellent antibacterial activity against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria, higher hydrophobicity (WCA changed from 00 to >1000), UV radiation resistance, and wash durability. Overall, this work provides new insights regarding the bifunctionalization of flax fabrics with Ag/ZnO nanostructures and brings new findings about the combined effect of both NPs for the development of piezoresistive textile sensors with multifunctional properties.The authors are thankful to TSSiPRO project, operation code NORTE 01-0145-FEDER-000015, supported by the "Programa Operacional Regional do Norte" number NORTE-45-2015-02 and the FCT (Portuguese Science Foundation) for Armando Ferreira grant: SFRH/BPD/102402/2014.info:eu-repo/semantics/publishedVersio

Adapter Incremental Continual Learning of Efficient Audio Spectrogram Transformers

Continual learning involves training neural networks incrementally for new tasks while retaining the knowledge of previous tasks. However, efficiently fine-tuning the model for sequential tasks with minimal computational resources remains a challenge. In this paper, we propose Task Incremental Continual Learning (TI-CL) of audio classifiers with both parameter-efficient and compute-efficient Audio Spectrogram Transformers (AST). To reduce the trainable parameters without performance degradation for TI-CL, we compare several Parameter Efficient Transfer (PET) methods and propose AST with Convolutional Adapters for TI-CL, which has less than 5% of trainable parameters of the fully fine-tuned counterparts. To reduce the computational complexity, we introduce a novel Frequency-Time factorized Attention (FTA) method that replaces the traditional self-attention in transformers for audio spectrograms. FTA achieves competitive performance with only a factor of the computations required by Global Self-Attention (GSA). Finally, we formulate our method for TI-CL, called Adapter Incremental Continual Learning (AI-CL), as a combination of the "parameter-efficient" Convolutional Adapter and the "compute-efficient" FTA. Experiments on ESC-50, SpeechCommandsV2 (SCv2), and Audio-Visual Event (AVE) benchmarks show that our proposed method prevents catastrophic forgetting in TI-CL while maintaining a lower computational budget

Painlev\'e Analysis, Prelle-Singer Approach, Symmetries and Integrability of Damped H\'enon-Heiles System

We consider a modified damped version of H\'enon-Heiles system and investigate its integrability. By extending the Painlev\'e analysis of ordinary differential equations we find that the modified H\'enon-Heiles system possesses the Painlev\'e property for three distinct parametric restrictions. For each of the identified cases, we construct two independent integrals of motion using the well known Prelle-Singer method. We then derive a set of nontrivial non-point symmetries for each of the identified integrable cases of the modified H\'enon-Heiles system. We infer that the modified H\'enon-Heiles system is integrable for three distinct parametric restrictions. Exact solutions are given explicitly for two integrable cases.Comment: Accepted for publication in Journal of Mathematical Physic

Tropomyosin - master regulator of actin filament function in the cytoskeleton.

Tropomyosin (Tpm) isoforms are the master regulators of the functions of individual actin filaments in fungi and metazoans. Tpms are coiled-coil parallel dimers that form a head-to-tail polymer along the length of actin filaments. Yeast only has two Tpm isoforms, whereas mammals have over 40. Each cytoskeletal actin filament contains a homopolymer of Tpm homodimers, resulting in a filament of uniform Tpm composition along its length. Evidence for this ‘master regulator’ role is based on four core sets of observation. First, spatially and functionally distinct actin filaments contain different Tpm isoforms, and recent data suggest that members of the formin family of actin filament nucleators can specify which Tpm isoform is added to the growing actin filament. Second, Tpms regulate whole-organism physiology in terms of morphogenesis, cell proliferation, vesicle trafficking, biomechanics, glucose metabolism and organ size in an isoform-specific manner. Third, Tpms achieve these functional outputs by regulating the interaction of actin filaments with myosin motors and actin-binding proteins in an isoform-specific manner. Last, the assembly of complex structures, such as stress fibers and podosomes involves the collaboration of multiple types of actin filament specified by their Tpm composition. This allows the cell to specify actin filament function in time and space by simply specifying their Tpm isoform composition

Hypoxia and Extracellular Matrix Proteins Influence Angiogenesis and Lymphangiogenesis in Mouse Embryoid Bodies

Regulatory mechanisms for angiogenesis are relatively well established compared to lymphangiogenesis. Few studies have shown that a combination of vascular endothelial growth factor VEGF-A/C with hypoxia or collagen matrix promotes lymphatic structures along with blood vessel development in mouse embryoid bodies (EB). In this study we tested the hypothesis that while hypoxia combined with prolonged VEGF-A/C treatment would induce early lymphangiogenesis in addition to angiogenesis in mouse EBs, under similar conditions specific extracellular matrix (ECM) proteins would promote lymphatic vessel-like structures over angiogenesis. EBs were subjected to four conditions and were maintained under normoxia and hypoxia (21% and 2.6% O2, respectively) with or without VEGF-A/C. Microarray analyses of normoxic and hypoxic EBs, and immunofluorescence data showed very low expression of early lymphatic endothelial cell (LEC) markers, lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1), and prospero-related homeobox 1 (Prox1) at early time points. Double immunofluorescence using MECA-32 and Prox1/LYVE1 demonstrated that combined hypoxia and VEGF-A/C treatment promoted formation of blood vessel-like structures, whereas only Prox1+/LYVE1+ LECs were detected in EBs at E22.5. Furthermore, EBs were grown on laminin or collagen-I coated plates and were subjected to the four treatments as described above. Results revealed that LECs in EBs at E36.5 attached better to collagen-I, resulting in an organized network of lymphatic vessel-like structures as compared to EBs grown on laminin. However, blood vessel-like structures were less favored under these same conditions. Collectively, our data demonstrate that hypoxia combined with growth factors promotes angiogenesis, whereas combination of these conditions with specific ECM proteins favors lymphangiogenesis processes in mouse EBs

Audio-Visual Deception Detection: DOLOS Dataset and Parameter-Efficient Crossmodal Learning

Deception detection in conversations is a challenging yet important task, having pivotal applications in many fields such as credibility assessment in business, multimedia anti-frauds, and custom security. Despite this, deception detection research is hindered by the lack of high-quality deception datasets, as well as the difficulties of learning multimodal features effectively. To address this issue, we introduce DOLOS\footnote {The name ``DOLOS" comes from Greek mythology.}, the largest gameshow deception detection dataset with rich deceptive conversations. DOLOS includes 1,675 video clips featuring 213 subjects, and it has been labeled with audio-visual feature annotations. We provide train-test, duration, and gender protocols to investigate the impact of different factors. We benchmark our dataset on previously proposed deception detection approaches. To further improve the performance by fine-tuning fewer parameters, we propose Parameter-Efficient Crossmodal Learning (PECL), where a Uniform Temporal Adapter (UT-Adapter) explores temporal attention in transformer-based architectures, and a crossmodal fusion module, Plug-in Audio-Visual Fusion (PAVF), combines crossmodal information from audio-visual features. Based on the rich fine-grained audio-visual annotations on DOLOS, we also exploit multi-task learning to enhance performance by concurrently predicting deception and audio-visual features. Experimental results demonstrate the desired quality of the DOLOS dataset and the effectiveness of the PECL. The DOLOS dataset and the source codes are available at https://github.com/NMS05/Audio-Visual-Deception-Detection-DOLOS-Dataset-and-Parameter-Efficient-Crossmodal-Learning/tree/main.Comment: 11 pages, 6 figure

Atomic Force Microscopy Protocol for Measurement of Membrane Plasticity and Extracellular Interactions in Single Neurons in Epilepsy

Physiological interactions between extracellular matrix (ECM) proteins and membrane integrin receptors play a crucial role in neuroplasticity in the hippocampus, a key region involved in epilepsy. The atomic force microscopy (AFM) is a cutting-edge technique to study structural and functional measurements at nanometer resolution between the AFM probe and cell surface under liquid. AFM has been incrementally employed in living cells including the nervous system. AFM is a unique technique that directly measures functional information at a nanoscale resolution. In addition to its ability to acquire detailed 3D imaging, the AFM probe permits quantitative measurements on the structure and function of the intracellular components such as cytoskeleton, adhesion force and binding probability between membrane receptors and ligands coated in the AFM probe, as well as the cell stiffness. Here we describe an optimized AFM protocol and its application for analysis of membrane plasticity and mechanical dynamics of individual hippocampus neurons in mice with chronic epilepsy. The unbinding force and binding probability between ECM, fibronectin-coated AFM probe and membrane integrin were strikingly lower in dentate gyrus granule cells in epilepsy. Cell elasticity, which represents changes in cytoskeletal reorganization, was significantly increased in epilepsy. The fibronectin-integrin binding probability was prevented by anti-α5β1 integrin. Thus, AFM is a unique nanotechnique that allows progressive functional changes in neuronal membrane plasticity and mechanotransduction in epilepsy and related brain disorders

Impact of fly ash and banana fiber on mechanical performance of paver block concrete

Primjena betona ojačanog prirodnim vlaknima općenito se smatra održivim pristupom razvoju infrastrukture. Ovaj je rad istraživao glavne karakteristike betonskih opločnika proizvedenih primjenom letećeg pepela, pepela od ugljena, superplastifikatora i vlakana banane kao ojačanja vlakana. Pripremljena su vlakna banane (dužine 15 mm), nakon čega je uslijedila izrada i karakterizacija betonskih opločnika. U ovome istraživanju utjecaj vlakna banane (0,5 %, 1 %, 1,5 %, 2 % i 2,5 %) i dodataka (0,5 % stalno) upotrijebljeni su u različitim omjerima mješavina za izradu blokova za popločavanje kako bi se analizirala fizikalno-mehanička svojstva. Prikazano je da opločnici koji imaju udio od 2 % modificiranih vlakana banane (u odnosu na težinu letećeg pepela) pokazuju veću tlačnu čvrstoću (7,45 % za dupli vezani opločnik i 17,12 % za cik-cak opločnike), savojnu čvrstoću (14,99 % za dupli vezani opločnik i 8,67 % za cik-cak) i vlačnu čvrstoću dobivenu cijepanjem (12,182 % za dupli vezani opločnik i 9,971 % za cik-cak opločnike) u usporedbi s ostalim omjerima smjese. Uporaba modificiranih vlakana banane kao vlakana za armiranje pokazala se vrlo učinkovitom u poboljšanju mehaničkih svojstava i životnog vijeka opločnika, što može dovesti do smanjenja izrade.The use of concrete reinforced with natural fibres is globally considered a sustainable approach to infrastructure development. This study investigated the salient features of concrete paver blocks fabricated using fly ash, coal ash, superplasticiser, and banana fibres as fibre reinforcements. Banana fibres (15 mm in length) were prepared, followed by the fabrication and characterisation of concrete paver blocks. In the current study, banana fibre (0.5 %, 1 %, 1.5 %, 2 %, and 2.5 %) and admixture (0.5 % constantly) were used in different mix proportions in the fabrication of paver block to analyse the physicomechanical properties. The results demonstrated that the paver blocks containing 2 % modified banana fiber (with respect to weight of fly ash) show higher compressive strength (7.45 % for I-dumble and 17.12 % for zigzag paver blocks), flexural strength (14.99 % for I-dumble and 8.67 % for zigzag) and split tensile strength (12.182 % for I-dumble and 9.971 % for zigzag paver blocks), compared to other mix proportions. The use of modified banana fibres as reinforcement was found to be very effective in improving the mechanical properties and life span of paver blocks, which may lead to minimizing the preparation