The era of antibiotic resistance is a cause of increasing concern as bacteria continue to develop adaptive countermeasures against current antibiotics at an alarming rate. In recent years, studies have reported nanoparticles as a promising alternative to antibacterial reagents because of their exhibited antibacterial activity in several biomedical applications, including drug and gene delivery, tissue engineering, and imaging. Moreover, nanomaterial research has led to reports of a possible relationship between the morphological characteristics of a nanomaterial and the magnitude of its delivered toxicity. However, conventional synthesis of nanoparticles requires harsh chemicals and costly energy consumption. Additionally, the exact relationship between toxicity and morphology of nanomaterials has not been well established. Here, we review the recent advancements in synthesis techniques for silver, gold, copper, titanium, zinc oxide, and magnesium oxide nanomaterials and composites, with a focus on the toxicity exhibited by nanomaterials of multidimensions. This article highlights the benefits of selecting each material or metal-based composite for certain applications while also addressing possible setbacks and the toxic effects of the nanomaterials on the environment.

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Precipitation and air temperature are key drivers of watershed models. Currently there are many open-access gridded precipitation and air temperature datasets at different spatial and temporal resolutions over global or quasi-global scale. Motivated by the scarcity and substantial temporal and spatial gaps in ground measurements in Africa, this study evaluated the performance of three open-access precipitation datasets (i.e. CHIRPS (Climate Hazards Group InfraRed Precipitation with Station data), TRMM (Tropical Rainfall Measuring Mission) and CFSR (Climate Forecast System Reanalysis)) and one air temperature dataset (CFSR) in driving Soil and Water Assessment Tool (SWAT) model in simulation of daily and monthly streamflow in the upper Gilgel Abay Basin, Ethi temperature from sparse gauge stations were also used to drive SWAT model and the results were compared with those using open-access datasets. After a comprehensive comparison of a total of eight model scenarios with different combinations of precipitation and air temperature inputs, we draw the following conclusions: (1) using measured precipitation from even sparse available stations consistently yielded better performance in streamflow simulation than using all three open-access precipitation datasets; (2) using CFSR air temperature yielded almost identical performance in streamflow simulation to using measured air temperature from gauge stations; (3) among the three open-access precipitation, overall CHIRPS yielded best performance. These results suggested that the CHIRPS precipitation available at high spatial resolution (0.05 ) together with CFSR air temperature can be a promising alternative open-access data source for streamflow simulation in this data-scarce area in the case of limited access to desirable gauge data.

Abstract:The superior mechanical and tribological properties of diamond coatings suggest their promise for improving current orthopedic implants. Therefore, understanding and controlling biological responses on diamond coatings are important and necessary for their advancement in orthopedics. For this reason, the objective of the present study was to correlate surface properties of diamond coatings with osteoblast (OB) adhesion and proliferation. Diamond coatings on silicon of variable surface features (specifically, grain size, surface roughness and surface chemistry) were fabricated by microwave plasma enhanced chemical-vapor-deposition (MPCVD). Scanning electron microscopy (SEM) as well as atomic force microscopy (AFM) was applied for topographical characterization and contact angles were measured to assess surface wettability. Results revealed that the grain size, surface roughness and wettability of diamond coatings can be controlled by adjusting H 2 plasma in the MPCVD process. Further, results showed enhanced OB adhesion on nanocrystalline diamond (ND) with grain sizes less than 100 nm whereas nanostructured diamond/amorphous carbon coatings (NDp) and microcrystalline diamond (MD) inhibited OB adhesion. H 2 plasma treated ND (NDH) also promoted OB adhesion. Similarly, OB proliferated to a greater extent on ND and NDH compared with MD and uncoated silicon controls. In summary, surface properties (including topography and chemistry) of diamond coatings can be controlled to either promote or inhibit OB functions, which implies that various forms of diamond coatings can be used to either support or inhibit bone growth in different regions of an orthopedic implant.

Compared to conventional top-down photo-cleavage method, a facile bottom-up ink-combination method to in situ and rapidly achieve water wettability and adhesion transition, with a great contrast on the superamphiphobic TiO2 nanostructured film, is described. Moreover, such combination method is suitable for various kinds of superamphiphobic substrate. Oil-based ink covering or removing changes not only the topographical morphology but also surface chemical composition, and these resultant topographical morphology and composition engineering realize the site-selectively switchable wettability varying from superamphiphobicity to amphiphilicity, and water adhesion between sliding superamphiphobicity and sticky superamphiphobicity in micro-scale. Additionally, positive and negative micro-pattern can be achieved by taking advantage of the inherent photocatalytic property of TiO2 with the assistance of anti-UV light ink mask. Finally, the potential applications of the site-selectively sticky superamphiphobic surface were demonstrated. In a proof-of-concept study, the microdroplet manipulation (storage, moving, mixing, and transfer), specific gas sensing, wettability template for positive and negative ZnO patterning, and site-selective cell immobilization have been demonstrated. This study will give an important input to the field of advanced functional material surfaces with special wettability.

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While rapid wound healing is essential yet challenging, there is also an unmet need for functional restoration of sensation. Inspired by natural skin, an ultra‐conformable, adhesive multi‐functional ionic skin (MiS) with multi‐modal sensing capability is devised for smart and expedited wound care. The base of MiS is a unique skin‐like, conductive and self‐adaptive adhesive polyacrylamide/starch double‐network hydrogel (PSH) and self‐powered, flexible, triboelectric sensor(s) is integrated on top of PSH for multi‐tactile sensing. MiS could enhance wound contraction, collagen deposition, angiogenesis, and epidermis formation in a full‐thickness skin defect wound model in vivo, while significantly inhibiting the biofilm formation of a wide range of microorganisms. MiS also exhibits multi‐modal sensing capability for smart and instant therapeutics and diagnostics, including skin displacement or joint motion, temperature, pressure and tissue exudate changes of wound bed, and locally releasing drugs in a pH‐responsive manner. More importantly, MiS could restore the skin‐mimicking tactile sensing function of both touch location and intensity, and thus could be used as a human‐machine interface for accurate external robotic control. MiS demonstrates a new comprehensive paradigm of combining wound diagnosis and healing, broad‐spectrum anti‐microbial capability and restoration of multi‐tactile sensing for the reparation of severe wound.