Heavy metals polluted soils have turned out to be a common environmental problem across the globe due to their toxic effects and accumulation through the food chain. Heavy metals have lethal effects on all forms of life. For instance, plants grown on heavy metal polluted soil show a reduction in growth and yields. A surge in anthropogenic activities and industrial operations has substantially increased the level of heavy metal pollution and release into the environment; hence, there is need to remediate these heavy metal pollutants. Biosorption is an efficient, economical, ecofriendly and convenient techniques of remediating heavy metal polluted soils. It is a widely accepted method that utilizes biomaterials such as natural biomass as biosorbents. The current study was based on the biosorption of copper, chromium, cadmium and nickel polluted soil using bacteria and fungi isolated from soil. Bacterial species isolated were Pseudomonas, Bacillus, Micrococcus, Escherichia, Streptococcus, Enterobacter and Staphylococcus while fungi isolated were Aspergillus niger, Penicillium notatum and Aspergillus flavus. The isolated bacteria were screened for potential to biosorb copper and chromium likewise fungi for cadmium and nickel. Biosorption rate was determined using atomic absorption spectrophotometry. Five milliliters each of a-day-old culture of the screened bacteria and fungi was inoculated into 45 ml of nutrient broth (bacteria) and potato dextrose broth (fungi) having concentrations of 5, 10, 15 and 20 ppm, respectively, of copper, chromium, cadmium and nickel. The conical flasks were incubated at a temperature of 37 °C and 28 °C ± 2 for bacteria and fungi, respectively, for a period of 35 days of inoculation. For the bacterial isolates, the highest biosorption rates of chromium (89.67%) and copper (90.89%) by Pseudomonas aeruginosa were observed at 20 ppm on day 21 and 15 ppm on day 14, respectively, while for the fungi isolates, P. notatum showed highest biosorption rate for cadmium at 10 ppm with 77.67%. Aspergillus niger showed highest biosorption rate for nickel with 81.07% after 28 days of incubation. The results of this study revealed the ability of Pseudomonas aeruginosa to biosorb copper and chromium and also A. niger and P. notatum to biosorb cadmium and nickel from the environment and can be developed for the biosorption of soils polluted with copper, chromium, cadmium and nickel.

Additive manufacturing of aluminum alloys is considered a promising layer-wise manufacturing method which can produce lightweight critical automotive/aerospace/military components with enhanced physical and mechanical properties. This paper aims at assessing the correlation between microstructure and small-scale characteristics of an additive manufactured AlSi10Mg alloy in the as-printed and heat treated conditions. Depth-sensing nanoindentation testing, as a non-destructive, robust, and convenient testing approach, along with microstructural assessments, using optical microscopy and scanning electron microscopy, were employed to compare the nano-hardness of the printed (selective laser melting method) and the heat treated (age-hardening) materials. Considering the distance from the build plate, a gradation in the cooling rate, and therefore the microstructure, is expected which directly affect the nano-hardness gradient along the deposition direction. Results show a transition in the microstructure from cellular grains, with coral-like silicon fiber colonies, to fragmented/spheroidized eutectic silicon particles upon the heat treatment. Unlike conventionally manufactured AlSi10Mg alloys, upon aging heat treatment in the additive manufactured AlSi10Mg alloy, the nano-hardness is decreased which is mainly contributed to stress relief, elimination of solid solution strengthening, and silicon spheroidization phenomena. These are considered in detail in the current paper.

The organism Caenorhabditis elegans is a performant model system for studying human biological processes and diseases, but until now all phenome data are produced as population-averaged read-outs. Monitoring of individual responses to drug treatments would however be more informative. Here, a new strategy to track different phenotypic traits of individual C. elegans nematodes throughout their full life-cycle—i.e., embryonic and post-embryonic development, until adulthood onset, differently from life-span—is presented. In an automated fashion, single worms were synchronized, isolated, and cultured from egg to adulthood in a microfluidic device, where their identity was preserved during their whole development. Several phenotypes were monitored and quantified for each animal, resulting in high-content phenome data. Specifically, the method was validated by analyzing the response of C. elegans to doxycycline, an antibiotic fairly well-known to prolong the development and activate mitochondrial stress-response pathways in different species. Interestingly, the obtained extensive single-worm phenome not only confirmed the dramatic doxycycline effect on the worm developmental delay, but more importantly revealed subtle yet severe treatment-dependent phenotypes that are representative of minority subgroups and would have otherwise stayed hidden in an averaged dataset. Such heterogeneous response started during the embryonic development, which makes essential having a dedicated chip that allows including this early developmental stage in the drug assay. Our approach would therefore allow elucidating pharmaceutical or therapeutic responses that so far were still being overlooked.

The role of structure has been always considered essential in understanding the architecture. In the historical buildings of Iran, the function of structural elements follows the general form of the building. In this study, the modern structural analysis of historical building aimed at discovering the deep knowledge of experienced and skilled constructors in their works, developing the modern structural theories, and establishing modern solutions for strengthening of structural elements. Taj-Ol-Molk Dome was used as the case study that it is entitled to “the most beautiful dome”. In this study, the qualitative and interpretive method was used to explore the role of aesthetics in Iranian domes. In the structural analysis based on structural simulation, the total displacement was less than 0.0002 at the maximum mode. In addition, the Von-Mises stress at the joint bearing surfaces was 2.3 × 10⁶–3.5 × 10⁶ which was less than the yield stress of the materials. Based on Mohr–Coulomb theory, the entire structure is below the standard risk level. A variety of brickwork styles were used based on mathematical calculations to reduce applied forces to the building. The form of Taj-Ol-Molk Dome is completely in harmony with the catenary curve form. The structural patterns lead to the bearing stress as completely compressive and without tensile and bending stress. Based on the findings, the golden ratio in the façade of building coordinated the cross section and dome-span. Finally, the structural features of the dome and the principles of structural aesthetic vision of the building are explained.

The present report explores the discussion on 3D flow of dual stratified Oldroyd-B fluid in the direction of thermal radiation, viscous dissipation and heat source/sink. Mathematical modeling is formulated with an applied magnetic field through a stretching surface. The present flow governing system has been transformed as nonlinear ODE via suitable transformations and then concluded by using bvp4c. The graphs are described and illustrated for various non-dimensional parameters. Thermal stratification and Prandtl number parameters reduce the temperature, whereas thermal radiation and heat source parameters show reverse behavior. Numerical results are used to obtain the values of frictional drag, rate of heat and mass transfers. Finally, numerical results are compared with previous established work in a limiting case.

Reinforced epoxy composite adhesives of expanded graphite (EG) and graphene nanoplatelet (GNPs) were prepared by hand layup and mechanical mixing method. Disk-shaped epoxy composite samples with EG and GNP mixtures in varying ratios were prepared to measure the thermal conductivity (TC) enhancement. Thermal characterization testing data showed high thermal conductivity enhancement with three different hybrid filler concentrations of 10, 25, and 35 wt%, respectively. The highest thermal conductivity of 3.6 W/m K was obtained for an epoxy adhesive composite having 30 wt.% EG and 5 wt.% GNP which was tested by guarded heat flow meter technique. This significant improvement in thermal conductivity can be attributed to the lowering of overall thermal interface resistance due to small amounts of nanofiller (GNP) improving the thermal contact between the primary microfillers (graphite). The synergistic effect of this hybrid filler system is lost at higher loadings of the GNP relative to expanded graphite. The structure of the graphite flake, GNP/epoxy, EG/epoxy and hybrid EG/GNP/epoxy composites was investigated by XRD. The EG prepared by acid intercalation and abrupt thermal expansion showed good compatibility with GNP and the epoxy resin. From scanning electron microscopy photographs, the formation of conducting network observed through the expanded graphite and GNPs in a low conducting epoxy matrix. The thermal decomposition temperature of the composite increased to 450 and 615 °C with the addition of 10 and 35 wt% of hybrid EG/GNP inside epoxy matrix, respectively. LAP shear strength of single and hybrid filled epoxy adhesive decreased at 35 wt.% loading than neat epoxy.

Advancements have been made to injectable polymer technologies following the development of minimally invasive techniques for bone and tooth treatment. To improve the conversion rate and avoid potential toxicity of traditional injectable polymer, new injectable adhesives have been developed to ensure good biocompatibility, while optimizing their suitable mechanical and antibacterial properties. In this study, we synthesized a two-part injectable n-HA/Ag₃PO₄/polyurethane system (PU) featuring different contents of nanohydroxyapatite (n-HA) and silver salt (Ag₃PO₄). After the prepolymer (Part A) mixed with a hardener (Part B), the compounded adhesive was injected into pores and set in situ with antibacterial properties. The results indicated that a high conversion rate reached 95% within 24 h could effectively reduce the release of a toxic monomer. Among these composites, the incorporation of n-HA in PU was the critical factor to ensure the adhesive’s material characteristics and cytocompatibility. With the increased content of n-HA, from 0 to 30 wt%, the compressive strength, setting time, surface wettability, and differentiation activities improved significantly. Although the injectability and setting time of the PUs decreased with the increase of n-HA, the values of injectable PUs still met with ISO standard requirements. The antibacterial tests against Staphylococcus aureus showed that the incorporation of Ag₃PO₄ in PUs (1 wt% and 3 wt%) exhibited stronger antimicrobial effects than that without the addition of silver. Compared to the PUs with the addition of 3 wt% Ag₃PO₄, which led to poor cellular viability, PUs with 1 wt% Ag₃PO₄not only offered good antimicrobial properties, but also expressed excellent cytocompatibility, suggesting that this agent might be a promising injectable adhesive system.