Kinematic and dynamic study of a manipulator 1T6R

The paper presents in detail a method of calculating the forces acting on a 1T6R robot manipulator. To determine the reactions (forces in kinematic torques), you must first determine the inertial forces in the mechanism to which one or more payloads of the robot can be added. The torsion of the inertial forces is calculated using the masses of the machine elements and the accelerations at the centers of mass of the elements of the mechanism, so that the positions, speeds, and accelerations acting on it, ie its complete kinematics, will be determined. Equations of the dynamics are also determined through an original method

Chemical vapor deposition of low reflective cobalt (II) oxide films

Low reflective CoO coatings are processed by chemical vapor deposition from Co2(CO)8at temperatures between 120◦C and 190◦C without additional oxygen source. The optical reflectivity in the visible and near infrared regions stems from 2 to 35% depending on deposition temperature. The combination of specific microstructural features of the coatings, namely a fractal “cauliflower” morphology and a grain size distribution more or less covering the near UV and IR wavelength ranges enhance light scattering and gives rise to a low reflectivity. In addition, the columnar morphology results in a density gradient in the vertical direction that we interpret as a refractive index gradient lowering reflectivity further down.The coating formed at 180◦C shows the lowest average reflectivity (2.9%), and presents an interesting deep black diffuse aspect

Ecobiophysical Aspects on Nanosilver Biogenerated from Citrus reticulata

In recent years, a considerable interest was paid to ecological strategies in management of plant diseases and plant growth. Metallic nanoparticles (MNPs) gained considerable interest as alternative to pesticides due to their interesting properties. Green synthesis of MNPs using plant extracts is very advantageous taking into account the fact that plants are easily available and eco-friendly and possess many phytocompounds that help in bioreduction of metal ions. In this research work, we phytosynthesized AgNPs from aqueous extract of Citrus reticulata peels, with high antioxidant, antibacterial, and antifungal potential. These “green” AgNPs were characterized by modern biophysical methods (absorption and FTIR spectroscopy, AFM, and zeta potential measurements). The nanobioimpact of Citrus-based AgNPs on four invasive wetland plants, Cattail (Typha latifolia), Flowering-rush (Butomus umbellatus), Duckweed (Lemna minor), and Water-pepper (Polygonum hydropiper), was studied by absorption spectroscopy, by monitoring the spectral signature of chlorophyll. The invasive plants exhibited different behavior under AgNP stress. Deep insights were obtained from experiments conducted on biomimetic membranes marked with chlorophyll a. Our results pointed out the potential use of Citrus-based AgNPs as alternative in controlling pathogens in aqueous media and in management of aquatic weeds growth

The Experimental Development of Bread with Enriched Nutritional Properties Using Organic Sea Buckthorn Pomace

In this study, sea buckthorn (Hippophae rhamnoides L.) pomace resulting from juice extraction was dried and ground in order to obtain a powder that was further used in bread making. Sea buckthorn pomace, an invaluable by-product of the industry, contains bioactive compounds and dietary fibers that promote health. Dried by-products of sea buckthorn are rich sources of nutritional and bioactive compounds, offering great potential for use as nutraceuticals in animal feed, ingredients in functional food, and the pharmaceutical industry. The utilization of sea buckthorn by-products promotes a circular and sustainable economy by implementing innovative methods and strategic approaches to recover high-value products and minimize waste in multiple ways. For this purpose, three organic sea buckthorn varieties were used, namely Mara (M), Clara (C), and Sorana (S). Further, 6%, 8%, and 10% pomace powder were added to wheat flour to prepare functional bread, and its effects on structural, nutritional, and sensorial characteristics were investigated. The volume, porosity, and elasticity of the obtained bread samples were slightly lower compared to the control sample (white bread). The nutritional characteristics revealed that the developed bread presented higher antioxidant activity, polyphenolic content, and crude fiber compared to the control sample. The acceptability test showed that consumer preferences were directed toward the bread samples containing 8% sea buckthorn powder, regardless of the variety, while the addition of 10% pomace powder led to major sensorial changes. The results of this study showed that sea buckthorn pomace powder can be successfully incorporated into bread in order to obtain a food product with enhanced properties

Modelling and simulation of a waste sorting mechatronic system for multi-floor residential buildings

The paper presents modelling and simulation of a mechatronic sorting system for residential buildings where the “wet” garbage can be used as fuel in an energy generation system. The proposed system can be used for the implementation of a selective storage model in the actual garbage chute system. The proposed system will have five different storage capacities that can be recycled: paper, glass, plastic packaging, metal boxes and organic household waste

Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes

In the last decade, building biohybrid materials has gained considerable interest in the field of nanotechnology. This paper describes an original design for bionanoarchitectures with interesting properties and potential bioapplications. Multilamellar lipid vesicles (obtained by hydration of a dipalmitoyl phosphatidylcholine thin film) with and without cholesterol were labelled with a natural photopigment (chlorophyll a), which functioned as a sensor to detect modifications in the artificial lipid bilayers. These biomimetic membranes were used to build non-covalent structures with single-walled carbon nanotubes. Different biophysical methods were employed to characterize these biohybrids such as: UV–vis absorption and emission spectroscopy, zeta potential measurements, AFM and chemiluminescence techniques. The designed, carbon-based biohybrids exhibited good physical stability, good antioxidant and antimicrobial properties, and could be used as biocoating materials. As compared to the cholesterol-free samples, the cholesterol-containing hybrid structures demonstrated better stability (i.e., their zeta potential reached the value of −36.4 mV), more pronounced oxygen radical scavenging ability (affording an antioxidant activity of 73.25%) and enhanced biocidal ability, offering inhibition zones of 12.4, 11.3 and 10.2 mm in diameter, against Escherichia coli, Staphylococcus aureus and Enterococcus faecalis, respectively

Burdock-Derived Composites Based on Biogenic Gold, Silver Chloride and Zinc Oxide Particles as Green Multifunctional Platforms for Biomedical Applications and Environmental Protection

Green nanotechnology is a rapidly growing field linked to using the principles of green chemistry to design novel nanomaterials with great potential in environmental and health protection. In this work, metal and semiconducting particles (AuNPs, AgClNPs, ZnO, AuZnO, AgClZnO, and AuAgClZnO) were phytosynthesized through a “green” bottom-up approach, using burdock (Arctium lappa L.) aqueous extract. The morphological (SEM/TEM), structural (XRD, SAED), compositional (EDS), optical (UV–Vis absorption and FTIR spectroscopy), photocatalytic, and bio-properties of the prepared composites were analyzed. The particle size was determined by SEM/TEM and by DLS measurements. The phytoparticles presented high and moderate physical stability, evaluated by zeta potential measurements. The investigation of photocatalytic activity of these composites, using Rhodamine B solutions’ degradation under solar light irradiation in the presence of prepared powders, showed different degradation efficiencies. Bioevaluation of the obtained composites revealed the antioxidant and antibacterial properties. The tricomponent system AuAgClZnO showed the best antioxidant activity for capturing ROS and ABTS•+ radicals, and the best biocidal action against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The “green” developed composites can be considered potential adjuvants in biomedical (antioxidant or biocidal agents) or environmental (as antimicrobial agents and catalysts for degradation of water pollutants) applications

Gene Expression of Indoleamine 2,3 Dioxygenase 1, Insulin-Growth Factor 1 and Red/IK Cytokine in Alopecia Areata

Alopecia areata (AA) is a chronic, T-cell mediated autoimmune disease directed against the hair follicle, which partially evolves due to a loss of the immune privilege of the anagen hair follicle. The immune privilege is maintained by several factors, including a downregulation of MHC class I and II, local immunosupressants and expression of Fas ligand. The purpose of the study was to evaluate several factors involved in the collapse and restoration of the immune privilege. We investigated IDO1, IGF1 and red/IK gene expression in lesional and perilesionalscalp biopsies from alopecia areata patients. Seven paired punch-biopsies were taken from the active edge of alopecic plaque and from the perilesional scalp. Expression of IDO1, IGF1 and red/IK genes was performed by qRT-PCR. In lesional tissue, IGF1, IDO1 and red/IK genes showed an increase in the mRNA levels as compared with the perilesional scalp. By comparing the pairs of data for the investigated genes, IDO1was statistically upregulated in the lesional area. No significant differences were observed between the gene expression in mild or severe AA, from the lesional or perilesional areas. IDO1 mRNA expression was higher in patients with a relapse duration of less than 6 months as compared to patients with a relapse duration of more than 6 months; levels of IGF1 and red/IK mRNA are increased in lesionals compared to perilesional scalp area

Cytotoxicity, Antioxidant, Antibacterial, and Photocatalytic Activities of ZnO–CdS Powders

In this work, ZnO–CdS composite powders synthesized by a simple chemical precipitation method were thoroughly characterized. The morphological, structural, compositional, photocatalytical, and biological properties of the prepared composites were investigated in comparison with those of the pristine components and correlated with the CdS concentration. ZnO–CdS composites contain flower-like structures, their size being tuned by the CdS amount added during the chemical synthesis. The photocatalytic activity of the composites was analyzed under UV irradiation using powders impregnated with methylene blue; the tests confirming that the presence of CdS along the ZnO in composites can improve the dye discoloration. The biological properties such as antioxidant capacity, antibacterial activity, and cytotoxicity of the ZnO, CdS, and ZnO–CdS composites were evaluated. Thus, the obtained composites presented medium antioxidant effect, biocidal activity against Escherichia coli, and no toxicity (at concentrations less than 0.05 mg/mL for composites with a low CdS amount) for human fibroblast cells. Based on these results, such composites can be used as photocatalytic and/or biocidal additives for photoactive coatings, paints, or epoxy floors, which in their turn can provide a cleaner and healthier environment

Correction: Zgura et al. Cytotoxicity, Antioxidant, Antibacterial, and Photocatalytic Activities of ZnO–CdS Powders. Materials 2020, 13, 182

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