The SARS‐CoV‐2 virus outbreak revealed that these nano‐pathogens have the ability to rapidly change lives. Undoubtedly, SARS‐CoV‐2 as well as other viruses can cause important global impacts, affecting public health, as well as, socioeconomic development. But viruses are not only a public health concern, they are also a problem in agriculture. The current treatments are often ineffective, are prone to develop resistance, or cause considerable adverse side effects. The use of nanotechnology has played an important role to combat viral diseases. In this review three main aspects are in focus: first, the potential use of nanoparticles as carriers for drug delivery. Second, its use for treatments of some human viral diseases, and third, its application as antivirals in plants. With these three themes, the aim is to give to readers an overview of the progress in this promising area of biotechnology during the 2017–2020 period, and to provide a glance at how tangible is the effectiveness of nanotechnology against viruses. Future prospects are also discussed. It is hoped that this review can be a contribution to general knowledge for both specialized and non‐specialized readers, allowing a better knowledge of this interesting topic.

In article number 2000067 Lin Yang and co-workers find that the hydrophobic interaction between the SARS-CoV-2 spike protein and the ACE2 protein is significantly greater than that between the SARS-CoV spike protein and the ACE2 protein. At the docking site, the hydrophobic portions of the hydrophilic side chains of SARS-CoV-2 S are found to be involved in the hydrophobic interaction between the SARS-CoV-2 spike protein and ACE2.

Solar‐powered water evaporation is a primitive technology but interest has revived in the last five years due to the use of nanoenabled photothermal absorbers. The cutting‐edge nanoenabled photothermal materials can exploit a full spectrum of solar radiation with exceptionally high photothermal conversion efficiency. Additionally, photothermal design through heat management and the hierarchy of smooth water‐flow channels have evolved in parallel. Indeed, the integration of all desirable functions into one photothermal layer remains an essential challenge for an effective yield of clean water in remote‐sensing areas. Some nanoenabled photothermal prototypes equipped with unprecedented water evaporation rates have been reported recently for clean water production. Many barriers and difficulties remain, despite the latest scientific and practical implementation developments. This Review seeks to inspire nanoenvironmental research communities to drive onward toward real‐time solar‐driven clean water production.

The purpose of the study is to find out the psychological impact of the COVID‐19 pandemic on university students. The study focuses on the university students from different public and private universities of Bangladesh through a set of questionnaires according to the guideline of Generalized Anxiety Disorder Scale (GAD‐7). The result among 15 543 respondents shows that 44.59% are suffering from severe anxiety, 48.41% moderate anxiety, and only 3.82% mild anxiety. The results highlight that all epidemic‐related stressors are positively correlated with the level of anxiety. Among the epidemic‐related stressors, worry about economic influences during and after COVID‐19 (r = 0.342, p < 0.001) and worry about the influence of COVID‐19 on daily life (r = 0.340, p < 0.001) have a highly positive impact on the level of anxiety. Following these stressors, worry about academic delays due to COVID‐19 (r = 0.326, p < 0.001) and worry about the social support during COVID‐19 (r = 0.321, p < 0.001) have moderately and positively correlated with the level of anxiety. The study suggests that proper government support, as well as social awareness, should be monitored during epidemics for decreasing anxiety and maintaining a good mental health of the university students.

The discovery of Sanal flow choking is a scientific breakthrough and a paradigm shift in the diagnostics of the detonation/hemorrhage in real‐world fluid flow systems. The closed‐form analytical models capable of predicting the boundary‐layer blockage factor for both 2D and 3D cases at the Sanal flow choking for adiabatic and diabatic fluid flow conditions are critically reviewed here. The beauty and novelty of these models stem from the veracity that at the Sanal flow choking condition for diabatic flows all the conservation laws of nature are satisfied at a unique location, which allows for computational fluid dynamics (CFD) code verification. At the Sanal flow choking condition both the thermal choking and the wall‐friction‐induced flow choking occur at a single sonic fluid throat location. The blockage factor predicted at the Sanal flow choking condition can be taken as an infallible data for various in silico model verification, validation, and calibration. The 3D blockage factor at the Sanal flow choking is found to be 45.12% lower than the 2D case of a wall‐bounded diabatic fluid flow system with air as the working fluid. The physical insight of Sanal flow choking presented in this review article sheds light on finding solutions, through in silico experiments in base flow and nanoflows, for numerous unresolved problems carried forward over the centuries in physical, chemical, and biological sciences for humankind.

Membrane‐based technologies are attractive for remediating oily wastewater because they are relatively energy‐efficient and are applicable to a wide range of industrial effluents. For complete treatment of oily wastewater, removing dissolved contaminants from the water phase is typically followed by adsorption onto an adsorbent, which complicates the process. Here, an in‐air superhydrophilic and underwater superoleophobic membrane‐based continuous separation of surfactant‐stabilized oil‐in‐water emulsions and in situ decontamination of water by visible‐light‐driven photocatalytic degradation of dissolved organic contaminants is reported. The membrane is fabricated by utilizing a thermally sensitized stainless steel mesh coated with visible light absorbing iron‐doped titania nanoparticles. Post annealing of the membrane can enhance the adhesion of nanoparticles to the membrane surface by formation of a bridge between them. An apparatus that enables continuous separation of surfactant‐stabilized oil‐in‐water emulsion and in situ photocatalytic degradation of dissolved organic matter in the water‐rich permeate upon irradiation of visible light on the membrane surface with greater than 99% photocatalytic degradation is developed. The membrane demonstrates the recovery of its intrinsic water‐rich permeate flux upon continuous irradiation of light after being contaminated with oil. Finally, continuous oil−water separation and in situ water decontamination is demonstrated by photocatalytically degrading model toxins in water‐rich permeate.

In article number 2000001, Jurgen Kosel and co-workers design a wearable, flexible piezoresistive graphene sensor by a facile, one-step laser-printing fabrication process. The sensors feature long-term stability, biocompatibility, and a low detection limit in combination with an extensive dynamic range. They can function as wearable artificial skins, monitors for heart rate or plantar pressure, or provide a tactile sense. They can also be employed in harsh environments.

In article number 1900087, Goutam Kumar Dalapati and co-workers develop a low cost, stable and efficient photocathode for sun-light driven hydrogen generation. Copper oxide (CuO) functionalized with graphene enhances hydrogen generation through water splitting in presence of solar radiation. Hydrogen generation in this way is an effective path to address global challenges and can be used to minimize global warming by promoting hydrogen based green economy.