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Progress in atom visualization and miniaturization in microelectronics resulted in the discovery of nanomaterials in the second half of the 20th century [...].Progress in atom visualization and miniaturization in microelectronics resulted in the discovery of nanomaterials in the second half of the 20th century [...].

Nanosilver with sizes 1–100 nm at least in one dimension is widely used due to physicochemical, anti-inflammatory, anti-angiogenesis, antiplatelet, antifungal, anticancer, antibacterial, and antiviral properties. Three modes of the nanosilver action were suggested: “Trojan horse”, inductive, and quantum mechanical. The Ag+ cations have an affinity to thiol, amino, phosphate, and carboxyl groups. Multiple mechanisms of action towards proteins, DNA, and membranes reduce a risk of pathogen resistance but inevitably cause toxicity for cells and organisms. Silver nanoparticles (AgNP) are known to generate two reactive oxygen species (ROS)-superoxide (•O2−) and hydroxyl (•OH) radicals, which inhibit the cellular antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and cause mechanical damage of membranes. Ag+ release and replacement by electrolyte ions with potential formation of insoluble AgCl result in NP instability and interactions of heavy metals with nucleic acids and proteins. Protein shells protect AgNP core from oxidation, dissolution, and aggregation, and provide specific interactions with ligands. These nanoconjugates can be used for immunoassays and diagnostics, but the sensitivity is limited at 10 pg and specificity is restricted by binding with protective proteins (immunoglobulins, fibrinogen, albumin, and others). Thus, broad implementation of Ag nanostructures revealed limitations such as instability; binding with major blood proteins; damage of proteins, nucleic acids, and membranes; and immunosuppression of the majority of cytokines.

This paper suggests a methodology (conception and principles) for building two-mode monitoring systems (SMs) for industrial facilities and their adjacent territories based on the application of unmanned aerial vehicle (UAV), Internet of Things (IoT), and digital twin (DT) technologies, and a set of SM reliability models considering the parameters of the channels and components. The concept of building a reliable and resilient SM is proposed. For this purpose, the von Neumann paradigm for the synthesis of reliable systems from unreliable components is developed. For complex SMs of industrial facilities, the concept covers the application of various types of redundancy (structural, version, time, and space) for basic components—sensors, means of communication, processing, and presentation—in the form of DTs for decision support systems. The research results include: the methodology for the building and general structures of UAV-, IoT-, and DT-based SMs in industrial facilities as multi-level systems; reliability models for SMs considering the applied technologies and operation modes (normal and emergency); and industrial cases of SMs for manufacture and nuclear power plants. The results obtained are the basis for further development of the theory and for practical applications of SMs in industrial facilities within the framework of the implementation and improvement of Industry 4.0 principles.

The reaction of aluminum with water is a promising method for producing hydrogen on demand for autonomous energy systems. However, its practical implementation faces the challenge of process control due to high exothermicity, leading to particle sintering and thermal instability, especially when using highly reactive nanopowders. The goal of this study is to implement an integrated approach to controlling this reaction, aimed at minimizing these risks. The approach is based on the principle of spatial and temporal distribution of reactants to ensure uniform heat release. Two process management methods were investigated: electrostatic application of aluminum powder to the reactor walls with its gradual release and pre-treatment of a nanopowder-ice mixture. Using a macrokinetic mathematical model, calculations of the conversion kinetics and heat release were performed and compared with experimental data. The results showed that both methods prevent slurry self-heating and achieve uniform hydrogen generation at a constant rate. In particular, the use of a pre-frozen mixture ensured stable hydrogen production over a long period of time without additional heating or stirring. The proposed approaches can be used in the design of safe and efficient hydrogen generators for autonomous power plants.

To support public health policymakers in Connecticut, we developed a flexible county-structured compartmental SEIR-type model of SARS-CoV-2 transmission and COVID-19 disease progression. Our goals were to provide projections of infections, hospitalizations, and deaths, and estimates of important features of disease transmission and clinical progression. In this paper, we outline the model design, implementation and calibration, and describe how projections and estimates were used to meet the changing requirements of policymakers and officials in Connecticut from March 2020 to February 2021. The approach takes advantage of our unique access to Connecticut public health surveillance and hospital data and our direct connection to state officials and policymakers. We calibrated this model to data on deaths and hospitalizations and developed a novel measure of close interpersonal contact frequency to capture changes in transmission risk over time and used multiple local data sources to infer dynamics of time-varying model inputs. Estimated epidemiologic features of the COVID-19 epidemic in Connecticut include the effective reproduction number, cumulative incidence of infection, infection hospitalization and fatality ratios, and the case detection ratio. We conclude with a discussion of the limitations inherent in predicting uncertain epidemic trajectories and lessons learned from one year of providing COVID-19 projections in Connecticut.

This dataset provides the Global Naturalized Alien Flora (GloNAF) database, version 1.2. GloNAF represents a data compendium on the occurrence and identity of naturalized alien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts, islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including 381 islands). The dataset is based on 210 data sources. For each taxon-by-region combination, we provide information on whether the taxon is considered to be naturalized in the specific region (i.e. has established self-sustaining populations in the wild). Non-native taxa are marked as “alien”, when it is not clear whether they are naturalized. To facilitate alignment with other plant databases, we provide for each taxon the name as given in the original data source and the standardized taxon and family names used by The Plant List Version 1.1 (http://www.theplantlist.org/). We provide an ESRI shapefile including polygons for each region and information on whether it is an island or a mainland region, the country and the Taxonomic Databases Working Group (TDWG) regions it is part of (TDWG levels 1–4). We also provide several variables that can be used to filter the data according to quality and completeness of alien taxon lists, which vary among the combinations of regions and data sources. A previous version of the GloNAF dataset (version 1.1) has already been used in several studies on, for example, historical spatial flows of taxa between continents and geographical patterns and determinants of naturalization across different taxonomic groups. We intend the updated and expanded GloNAF version presented here to be a global resource useful for studying plant invasions and changes in biodiversity from regional to global scales. We release these data into the public domain under a Creative Commons Zero license waiver (https://creativecommons.org/share-your-work/public-domain/cc0/). When you use the data in your publication, we request that you cite this data paper. If GloNAF is a major part of the data analyzed in your study, you should consider inviting the GloNAF core team (see Metadata S1: Originators in the Overall project description) as collaborators. If you plan to use the GloNAF dataset, we encourage you to contact the GloNAF core team to check whether there have been recent updates of the dataset, and whether similar analyses are already ongoing.

Ukraine has the second-largest HIV epidemic in Europe, with most new cases officially attributed to heterosexual transmission. Indirect evidence suggested substantial HIV transmission from people who inject drugs (PWID) to their sexual partners. This study examined the extent of heterosexual HIV transmission between PWID and non-drug-using adolescent girls and young women (AGYW). A cross-sectional survey recruited AGYW diagnosed with heterosexually-acquired HIV between 2016 and 2019 in nine regions of Ukraine. AGYW were asked to identify and refer their sexual partners ('Partners'), who subsequently underwent HIV testing, and, if positive, HCV testing. Both AGYW and Partners completed an interview assessing HIV risk behaviors prior to AGYW's HIV diagnosis. In August-December 2020, we enrolled 321 AGYW and 64 Partners. Among the Partners, 42% either self-reported IDU or were HCV-positive, indicating an IDU-related mode of HIV transmission. PWID Partners were more likely to report sexually transmitted infections (STI) and had lower educational levels. Of the 62 women who recruited at least one Partner, 40% had a PWID Partner. Within this subgroup, there was a higher prevalence of STIs (52% vs. 24%) and intimate partner violence (36% vs. 3%). Condom use was less common (52% vs. 38% reporting never use), and frequent alcohol or substance use before sex was higher (48% vs 30%) among AGYW with PWID Partner, although this difference did not reach statistical significance. Notably, 52% of women were aware of their Partners' IDU. At least 40% of heterosexual transmission among AGYW in Ukraine can be linked to PWID partners. Intensified, targeted HIV prevention efforts are essential for key and bridge populations (PWID and their sexual partners), addressing the biological and structural determinants of transmission between key and bridge populations, such as IDU- and HIV status disclosure, STIs, IPV, and stigma.

A global database of alien plants, showing that over 13,000 species, nearly 4% of the global flora, have become naturalized in a new location. Import and export of plant species Human activity has facilitated the spread of alien plant species around the globe, many of which have become naturalized on different continents. Mark van Kleunen et al . construct a global database of alien plant introductions, showing that more than 13,000 species — nearly 4% of the total flora — have become naturalized in a new location. North America has received the most alien plants, while the Pacific islands are accumulating them at the fastest pace, and the Northern Hemisphere is the predominant donor of alien species. All around the globe, humans have greatly altered the abiotic and biotic environment with ever-increasing speed. One defining feature of the Anthropocene epoch 1 , 2 is the erosion of biogeographical barriers by human-mediated dispersal of species into new regions, where they can naturalize and cause ecological, economic and social damage 3 . So far, no comprehensive analysis of the global accumulation and exchange of alien plant species between continents has been performed, primarily because of a lack of data. Here we bridge this knowledge gap by using a unique global database on the occurrences of naturalized alien plant species in 481 mainland and 362 island regions. In total, 13,168 plant species, corresponding to 3.9% of the extant global vascular flora, or approximately the size of the native European flora, have become naturalized somewhere on the globe as a result of human activity. North America has accumulated the largest number of naturalized species, whereas the Pacific Islands show the fastest increase in species numbers with respect to their land area. Continents in the Northern Hemisphere have been the major donors of naturalized alien species to all other continents. Our results quantify for the first time the extent of plant naturalizations worldwide, and illustrate the urgent need for globally integrated efforts to control, manage and understand the spread of alien species.

Limited membrane permeability and biodegradation hamper the intracellular delivery of the free natural or recombinant enzymes necessary for compensatory therapy. Nanoparticles (NP) provide relative protein stability and unspecific endocytosis-mediated cellular uptake. Our objective was the fabrication of NP from 7 biomedicine-relevant enzymes, including DNase I, RNase A, trypsin, chymotrypsin, catalase, horseradish peroxidase (HRP) and lipase, the analysis of their conformation stability and enzymatic activity as well as possible toxicity for eukaryotic cells. The enzymes were dissolved in fluoroalcohol and mixed with 40% ethanol as an anti-solvent with subsequent alcohol evaporation at high temperature and low pressure. The shapes and sizes of NP were determined by scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic light scattering (DLS). Enzyme conformations in solutions and in NP were compared using circular dichroism (CD) spectroscopy. The activity of the enzymes was assayed with specific substrates. The cytotoxicity of the enzymatic NP (ENP) was studied by microscopic observations and by using an MTT test. Water-insoluble ENP of different shapes and sizes in a range 50–300 nm consisting of 7 enzymes remained stable for 1 year at +4 °C without any cross-linking. CD spectroscopy of the ENP permitted us to reveal changes in proportions of α-helixes, β-turns and random coils in comparison with fresh enzyme solutions in water. Despite the minor conformation changes of the proteins in the ENP, the enzymes retained their substrate-binding and catalytic properties. Among the studied bioactive ENP, only DNase NP were highly toxic for 3 cell lines with granulation in 1 day posttreatment, whereas other NP were less toxic (if any). Taken together, the enzymes in the stable ENP retained their catalytic activity and might be used for intracellular delivery.

Photoinduced intramolecular electron transfer (ET) is essential for understanding charge transport in biological and synthetic systems. This study examines ET in peptide His-Glu-Tyr-Gly (1) and the conjugate His-Gln(BP)-Tyr-Gly (2) with benzophenone (BP) as a photoactive electron acceptor and His or Tyr as donors. Time-resolved and field-dependent chemically induced dynamic nuclear polarization (CIDNP) techniques were employed to investigate ET mechanisms and kinetics. Peptide 1 with 3,3’,4,4’-tetracarboxy benzophenone as a photosensitizer initially forms two types of radical with radical center at either His or Tyr residue, the consequent intra- and intermolecular ET electron transfer from Tyr residue to the His radical takes place with rate constants k e(intra) =(1.5±0.5)×10 5 s − 1 and k e(inter) =(1.3±0.4)×10 7 M − 1 s − 1 at pH 8.8. Conjugate 2 forms two types of biradicals under irradiation: with radical centers at Tyr and BP across the entire pH range, and with radical centers at His and BP at slightly basic pH. Field-dependent CIDNP revealed nonzero electronic exchange interaction (2J ex  = − 8.78 mT) at acidic pH, indicating proximity between BP and Tyr radicals. Low-field CIDNP spectra showed strong emissive polarization patterns, with pH-dependent exchange interaction and biradical geometry. Notably, no electron transfer from tyrosine to histidine radicals was observed in the conjugate 2, distinguishing its behavior from peptide 1.