Ultrasensitive molecular building block for biothiol NMR detection at picomolar concentrations

Magnetic resonance imaging (MRI) provides structural and functional information, but it did not probe chemistry. Chemical information could help improve specificity of detection. Herein, we introduce a general method based on a modular design to construct a molecular building block Xe probe to help image intracellular biothiols (glutathione (GSH), cysteine (Cys) and homocysteine (Hcy)), the abnormal content of which is related to various diseases. This molecular building block possesses a high signal-to-noise ratio and no background signal effects. Its detection threshold was 100 pM, which enabled detection of intracellular biothiols in live cells. The construction strategy can be easily extended to the detection of any other biomolecule or biomarker. This modular design strategy promotes efficiency of development of low-cost multifunctional probes that can be combined with other readout parameters, such as optical readouts, to complement 129Xe MRI to usher in new capabilities for molecular imaging.

Metasurface-enabled three-in-one nanoprints by multifunctional manipulations of light

In metasurface-based ultra-compact image display, color-nanoprints, gray-imaging elements, and binary-pattern-imaging elements are three different types of nanoprints, implemented with different mechanisms of light manipulation. Here, we show the three functional elements can be integrated together to form a "three-in-one" nanoprint with negligible crosstalk, merely with a single-cell nanostructured design approach. Specifically, by decoupling spectrum and polarization-assisted intensity manipulations of incident light, the proposed metasurface appears as a dual-color nanoprint under a broadband unpolarized light source illumination, while simultaneously displaying an independent continuous gray image and another binary-pattern in an orthogonal-polarization optical setup with different polarization controls. Our approach can increase the system integration and security of metasurfaces, which can be of interest to many advanced applications such as data storage, optical information encoding, high-end optical anti-counterfeiting, and optical information hiding.

Current advances and challenges in nanosheet-based wearable power supply devices

Nowadays, wearable devices mainly exist in the form of portable accessories with various functions, connecting various kinds of terminals like mobile phones to form various wearable systems. In a wearable system, the wearable power supply device is the key component as energy dispenser for all devices. Nanosheets, a kind of two-dimensional material, which always displays a high surface-to-volume ratio and thus is lightweight and has remarkable conductive as well as electrochemical properties, have become the optimal choice for wearable power supply devices. The development and status of nanosheet-based wearable power supply devices including nanosheet-based wearable batteries, nanosheet-based wearable supercapacitors, nanosheet-based wearable self-powered energy suppliers are introduced in this article. Besides, the future opportunities and challenges of wearable devices are discussed.

Nitro to amine reductions using aqueous flow catalysis under ambient conditions

A catalyst based on Pd on glass wool (Pd@GW) shows exceptional performance and durability for the reduction of nitrobenzene to aniline at room temperature and ambient pressure in aqueous solutions. The reaction is performed in a flow system and completed with 100% conversion under a variety of flow rates, 2 to 100 mLmin⁻¹ (normal laboratory fast flow conditions). Sodium borohydride or dihydrogen perform well as reducing agents. Scale-up of the reaction to flows of 100 mLmin⁻¹ also shows high conversions and robust catalytic performance. Catalyst deactivation can be readily corrected by flowing a NaBH₄ solution. The catalytic system proves to be generally efficient, performing well with a range of nitroaromatic compounds. The shelf life of the catalyst is excellent and its reusability after 6-8 months of storage showed the same performance as for the fresh catalyst.

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Palladium on glass wool catalyzes reduction of nitrobenzene to aniline

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Catalytic flow process at atmospheric temperature and pressure in aqueous media

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Facile catalyst synthesis using inexpensive glass wool and low palladium loading

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Sustainable chemical process using sodium borohydride or hydrogen gas

RHINOS: A lightweight portable electronic nose for real-time odor quantification in wastewater treatment plants

Quantification of odor emissions in wastewater treatment plants (WWTPs) is key to minimize odor impact to surrounding communities. Odor measurements in WWTPs are usually performed via either expensive and discontinuous olfactometry hydrogen sulfide detectors or via fixed electronic noses. We propose a portable lightweight electronic nose specially designed for real-time odor monitoring in WWTPs using small drones. The so-called RHINOS e-nose allows odor measurements with high spatial resolution, and its accuracy is only slightly worse than that of dynamic olfactometry. The device has been calibrated using odor samples collected in a WWTP in Spain over a period of six months and validated in the same WWTP three weeks after calibration. The promising results obtained support the suitability of the proposed instrument to identify the odor sources having the highest emissions, which may give a useful indication to the plant managers as regards odor control and abatement.

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A portable e-nose for real time odor quantification according to EN13725 is described

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The e-nose is installed on a small drone for dense spatial measurements

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The e-nose is demonstrated and validated in a wastewater treatment plant

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Errors in odor quantification are only slightly worse than dynamic olfactometry

Unlocking the bacterial contact-dependent antibacterial activity to engineer a biocontrol alliance of two species from natural incompatibility to artificial compatibility

Plant growth-promoting rhizobacteria (PGPR) contain various biocontrol bacteria with broad-spectrum antimicrobial activity, and their single species has been extensively applied to control crop diseases. The development of complex biocontrol community by mixing two or more PGPR members together is a promising strategy to enlarge the efficacy and scope of biocontrol. However, an effective method to assess the natural compatibility of PGPR members has not yet been established to date. Here, we developed such a tool by using the bacterial contact-dependent antibacterial activity (CDAA) as a probe. We showed that the CDAA events are common in two-species interactions in the four selected representative PGPRs, represented by the incompatible interaction of Lysobacter enzymogenes strain OH11 (OH11) and Lysobacter antibioticus strain OH13 (OH13). We further showed that the CDAA between OH11 and OH13 is jointly controlled by a contact-dependent killing device, called the type IV secretion system (T4SS). By deleting the respective T4SS synthesis genes, the T4SS in both strains was co-inactivated and this step unlocked  their natural CDAA, resulting in an engineered, compatible mutant alliance that co-displayed antibacterial and antifungal activity. Therefore, this study reveals that releasing bacterial CDAA is effective to rationally engineer the biocontrol community.

The Nurse+Engineer as the Prototype V-Shaped Professional

BACKGROUND

Descriptions of convergence research include promises to solve complex societal problems, such as environmental determinants of health and social determinants of health, through the integration of diverse disciplines, such as nursing and engineering, to create novel frameworks, such as the V-shaped professional.

PURPOSE

The purpose of this paper was to define the nurse+engineer as a prototypical V-shaped professional.

METHODS

Starting from a description of the I-shaped discipline of nursing and the I-shaped discipline of engineering, we follow an intentional pathway to define the concept of the nurse+engineer as a new V-shaped professional.

FINDINGS

Examples of the nurse+engineer at the bedside and the nurse+engineer in the community are highlighted to support a theoretical definition of the V-shaped nurse+engineer.

DISCUSSION

Implications of the nurse+engineer in the workforce and practical recommendations for training nurse+engineer professionals are provided to improve healthcare policy, practice, research, and education through scientific discovery and innovation.

Exosomal targeting and its potential clinical application

Exosomes are extracellular vesicles secreted by a variety of living cells, which have a certain degree of natural targeting as nano-carriers. Almost all exosomes released by cells will eventually enter the blood circulation or be absorbed by other cells. Under the action of content sorting mechanism, some specific surface molecules can be expressed on the surface of exosomes, such as tetraspanins protein and integrin. To some extent, these specific surface molecules can fuse with specific cells, so that exosomes show specific cell natural targeting. In recent years, exosomes have become a drug delivery system with low immunogenicity, high biocompatibility and high efficacy. Nucleic acids, polypeptides, lipids, or small molecule drugs with therapeutic function are organically loaded into exosomes, and then transported to specific types of cells or tissues in vivo, especially tumor tissues, to achieve targeting drug delivery. The natural targeting of exosome has been found and recognized in some studies, but there are still many challenges in effective clinical treatments. The use of the natural targeting of exosomes alone is incapable of accurately transporting the goods loaded to specific sites. Besides, the natural targeting of exosomes is still an open question in disease targeting and efficient gene/chemotherapy combined therapy. Engineering transformation and modification on exosomes can optimize its natural targeting and deliver the goods to a specific location, providing wide use in clinical treatment. This review summarizes the research progress of exosomal natural targeting and transformation strategy of obtained targeting after transformation. The mechanism of natural targeting and obtained targeting after transformation are also reviewed. The potential value of exosomal targeting in clinical application is also discussed.

Engineered neutrophil apoptotic bodies ameliorate myocardial infarction by promoting macrophage efferocytosis and inflammation resolution

Inflammatory response plays a critical role in myocardial infarction (MI) repair. The neutrophil apoptosis and subsequent macrophage ingestion can result in inflammation resolution and initiate regeneration, while the therapeutic strategy that simulates and enhances this natural process has not been established. Here, we constructed engineered neutrophil apoptotic bodies (eNABs) to simulate natural neutrophil apoptosis, which regulated inflammation response and enhanced MI repair. The eNABs were fabricated by combining natural neutrophil apoptotic body membrane which has excellent inflammation-tropism and immunoregulatory properties, and mesoporous silica nanoparticles loaded with hexyl 5-aminolevulinate hydrochloride (HAL). The eNABs actively targeted to macrophages and the encapsulated HAL simultaneously initiated the biosynthesis pathway of heme to produce anti-inflammatory bilirubin after intracellular release, thereby further enhancing the anti-inflammation effects. In in vivo studies, the eNABs efficiently modulated inflammation responses in the infarcted region to ameliorate cardiac function. This study demonstrates an effective biomimetic construction strategy to regulate macrophage functions for MI repair.

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Construction of engineered neutrophil apoptotic bodies to simulate natural neutrophil apoptosis.

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Engineered neutrophil apoptotic bodies with excellent inflammation-tropism and macrophage-specific targeting capacity.

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Engineered neutrophil apoptotic bodies enhance macrophage efferocytosis and reprogramming for inflammation resolution.

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Engineered neutrophil apoptotic bodies ameliorate myocardial infarction and promote cardiac tissue regeneration after MI.

A comparative review of artificial muscles for microsystem applications

Artificial muscles are capable of generating actuation in microsystems with outstanding compliance. Recent years have witnessed a growing academic interest in artificial muscles and their application in many areas, such as soft robotics and biomedical devices. This paper aims to provide a comparative review of recent advances in artificial muscle based on various operating mechanisms. The advantages and limitations of each operating mechanism are analyzed and compared. According to the unique application requirements and electrical and mechanical properties of the muscle types, we suggest suitable artificial muscle mechanisms for specific microsystem applications. Finally, we discuss potential strategies for energy delivery, conversion, and storage to promote the energy autonomy of microrobotic systems at a system level.

Fresh water production from atmospheric air: Technology and innovation outlook

Capturing water vapor from atmospheric air is a possible solution to local water scarcity, but it is very energy demanding. Energy consumption estimates of water-from-air technologies involving adsorption processes, thermo-responsive hydrophilicity switching polymers, air cooling processes, and reverse osmosis of deliquescent salt solutions reveal that these technologies are not competitive when compared with seawater desalination, and the use of fresh water and wastewater sources. They only become a viable option in the absence of local liquid water sources and when long-distance transport for socio-economic reasons is not an option. Of interest, direct solar-driven technology for water-from-air production is an attractive means to disentangle the local water-energy nexus. It is expected that climate change will accelerate the introduction of water-from-air technologies in local water supply schemes. The optimal water-from-air technology depends on the climate, relative humidity, and temperature profiles. A world map is presented, indicating the optimal geographic location for each technology.

A high-performance Al-air fuel cell using a mesh-encapsulated anode via Al-Zn energy transfer

Aluminum-air fuel cells attract more attention because of their high specific energy, low cost, and friendly environment. However, the problems of hydrogen evolution corrosion and low anode efficiency of aluminum-air fuel cells remain unresolved. Herein, we propose an aluminum-air fuel cell using a mesh-encapsulated anode, where the energy redistribution can be achieved and the discharge performance of the fuel cell can be highly improved. The results show that the highest inhibition efficiency is 73.930% when the aluminum plate is immersed in 6 M potassium hydroxide solution containing 100% zinc oxide. The highest anode efficiency is up to 61.740% when the fuel cell using a mesh-encapsulated anode is discharged at 20 mA/cm², which is more than 2 times than that of no mesh, and the highest capacity can reach 1839.842 mAh/g, which is 101.623% higher than before optimization. Thus, our studies are very instructive for the large-scale application of aluminum-air fuel cells.

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The energy redistribution strategy is proposed to inhibit Al self-corrosion

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A structure of mesh-encapsulated anode is designed to utilize the energy of dead zinc

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The anode efficiency of Al-air fuel cell is up to 61.740% at 20 mA/cm²

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The capacity of Al-air fuel cell can reach 1839.842 mAh/g at 20 mA/cm²

Generic water-based spray-assisted growth for scalable high-efficiency carbon-electrode all-inorganic perovskite solar cells

A water-based spray-assisted growth strategy is proposed to prepare large-area all-inorganic perovskite films for perovskite solar cells (PSCs), which involves in spraying of cesium halide water solution onto spin-coating-deposited lead halide films, followed by thermal annealing. With CsPbBr3 as an example, we show that as-proposed growth strategy can enable the films with uniform surface, full coverage, pure phase, large grains, and high crystallinity, which primarily benefits from the controllable CsBr loading quantity, and the use of water as CsBr solvent makes the reaction between CsBr and PbBr2 immune to PbBr2 film microstructure. As a result, the small-area (0.09 cm2) and large-area (1.00 cm2) carbon-electrode CsPbBr3 PSCs yield the record-high efficiencies of 10.22% and 8.21%, respectively, coupled with excellent operational stability. We also illustrate that the water-based spray-assisted deposition strategy is suitable to prepare CsPbCl3, CsPbIBr2, and CsPbI2Br films with outstanding efficiencies of 1.27%, 10.44%, and 13.30%, respectively, for carbon-electrode PSCs.

Strong histamine torsion Raman spectrum enables direct, rapid, and ultrasensitive detection of allergic diseases

Allergic diseases are closely related to degranulation and release of histamine and difficult to diagnose because non-allergic diseases also exhibit the same clinical symptoms as allergy. Here, we report direct, rapid, and ultrasensitive detection of histamine using low-frequency molecular torsion Raman spectroscopy. We show that the low-frequency (<200 cm-1) Raman spectral intensities are stronger by one order of magnitude than those of the high-frequency Raman ones. Density functional theory calculation and nuclear magnetic resonance spectroscopy identify the strong spectral feature to be from torsions of carbon-carbon single bonds, which produce large variations of the polarizability densities in the imidazole ring and ethyl amino side chain. Using an omniphobic substrate and surface plasmonic effect of Au@SiO2 nanoparticles, the detection limit (signal-noise ratio >3) of histamine reaches 10-8 g/L in water and 10-6 g/L in serum. This scheme thus opens new lines of inquiry regarding the clinical diagnosis of allergic diseases.

Panel Discussion: Covid-19, Technology and Ethics

The Covid-19 pandemic has led to considerable disruption and raised a number of issues for both individuals and society as a whole. Many of these issues have both technology and ethics dimensions. Several of them are discussed in this paper. In the session the authors will be making brief presentations from their perspectives and the experiences of Covid-19 in their different countries. This will be followed by a comment/question and answer session and final summing up by the authors.

Engineering and loading therapeutic extracellular vesicles for clinical translation: A data reporting frame for comparability

Extracellular vesicles (EVs) have emerged as new drug delivery systems as well as a regenerative cell-free effectors going beyond academic research to reach industrial research and development (R&D). Many proof-of-concept studies are now published describing the delivery of drugs, nanoparticles or biologics among which nucleic acids, proteins, viruses, etc. Their main interests rely on their intrinsic biocompatibility, targeting capabilities and biological activities. The possibility of loading EVs with exogenous therapeutic drug/nanoparticles or imaging tracers opens up the perspectives to extend EV therapeutic properties and enable EV tracking. Clinical translation is still hampered by the difficulty to produce and load EVs with large scale, efficient and cGMP methods. In this review, we critically discuss important notions related to EV engineering and the methods available with a particular focus on technologies fitted for clinical translation. Besides, we provide a tentative data reporting frame in order to support comparability and standardization in the field.

Creation of an engineered amide synthetase biocatalyst by the rational separation of a two-step nitrile synthetase

The synthesis of amides through acid and amine coupling is one of the most commonly-used reactions in medicinal chemistry, yet still requires atom-inefficient coupling reagents. There is a current demand to develop greener, biocatalytic approaches to amide bond formation. The nitriles synthetases (NSs) enzymes are a small family of ATP-dependent enzymes which catalyse the transformation of a carboxylic acid into the corresponding nitrile via an amide intermediate. The B. subtilis QueC (BsQueC) is a NS involved in the synthesis of 7-cyano-7-deazaguanine (CDG) natural products. Through sequence homology and structural analysis of BsQueC we identified three highly-conserved residues, which could potentially play important roles in NS substrate binding and catalysis. Rational engineering led to the creation of a NS K163A/R204A biocatalyst that converts the CDG acid into the primary amide, but does not proceed to the nitrile. This study suggests that NSs could be further developed for coupling agent-free, amide-forming biocatalysts.