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Biologists can now solve complex environmental problems by fabricate practical plant organisms, difficulties related to characterisation of cellular architectures of plant cells are often encountered which constrained the application of plant cells in synthetic biology. The objective of this study was to develop a automated, accurate and high-throughput quantitative analysis method ACFVA for single plant cell identification. ACFVA can address a variety of biological questions quantitatively of large number of plant cells automatically including standard assays (for example, cell localiztion, count and size) and complex morphological assays (for example, different fluorescence in cells). These assays can be used in a wide range of synthetic biology directions.

Contact electrification between water and a solid surface is crucial for physicochemical processes at water–solid interfaces. However, the nature of the involved processes remains poorly understood, especially in the initial stage of the interface formation. Here we report that H 2 O 2 is spontaneously produced from the hydroxyl groups on the solid surface when contact occurred. The density of hydroxyl groups affects the H 2 O 2 yield. The participation of hydroxyl groups in H 2 O 2 generation is confirmed by mass spectrometric detection of 18 O in the product of the reaction between 4-carboxyphenylboronic acid and 18 O–labeled H 2 O 2 resulting from 18 O 2 plasma treatment of the surface. We propose a model for H 2 O 2 generation based on recombination of the hydroxyl radicals produced from the surface hydroxyl groups in the water–solid contact process. Our observations show that the spontaneous generation of H 2 O 2 is universal on the surfaces of soil and atmospheric fine particles in a humid environment.

Solar energy-powered adsorption-based atmospheric water harvesting (ABAWH) is an emerging technology for freshwater production, especially in water-scarce regions that are remote and landlocked. Numerous water adsorbents have been used in ABAWH devices to convert molecule to liquid water. However, it is still challenging to harvest water from the air in cold winter, owing to the water adsorption of sorbents decreasing significantly at low temperature. Herein, we designed and fabricated an ABAWH device by integrating composited ionic liquids (CILs) with carbon nanotubes (CNTs) photothermal materials on the surface of cotton rod fibers. CILs extract water from the air. CNTs enable light-to-heat conversion and drive the solar evaporation process. Importantly, the cotton rods offer a backbone porous structure to maintain its internal temperature at 20 °C under solar irradiation, and thus promote the water adsorption performance of CILs at low environmental temperature. Freshwater is successfully harvested under environment temperature of 6 °C, 30% RH and solar irradiation intensity of 0.6 kW m−2. The water yield can achieve 1.49 kg per m2 per day in an outdoor environment. We believe that the ABAWH device offers a promising approach to effectively harvest water from the air at low temperature and humidity conditions.

Summary The sudden epidemic of COVID-19 has led to the shortage of urgently needed medical supplies and strained the global supply chain. At the early stage of the epidemic, the infection of a large number of unprotected health care workers, the inability of patients to receive adequate testing or treatment consequently resulted in the collapse of local medical systems. During this period, 3D printing communities were trying their best to share 3D printed anti-epidemic supplies and fill the gap between traditional production modes and global supply chain. The rapid, decentralized, high degree of freedom and very low threshold manufacturing technology demonstrated its great potential to rapidly respond to a public health emergency with new problems and challenges. This commentary reviews the exhibited capabilities and emerging challenges of 3D printing technology in this epidemic and provides practical suggestions for future rapid response to public health emergencies.

Herein, we demonstrate a sustainable strategy for scalable production of α-Fe2O3 nanocrystals on flexible carbon textiles via controllable chemical bath deposition process. The assembly of α-Fe2O3 nanocrystals is densely anchored onto the carbon textiles, and the temperature-dependent mass loading and crystal size of α-Fe2O3 are systematically investigated. As an integrated electrode for lithium-ion batteries, the optimized Fe2O3@CTs with ultrathin three-dimensional interconnected porous architectures achieves significantly enhanced cycling performance and rate capability attributing to the improved stability, electronic interconnection, and shortened solid state diffusion pathway for Li+ ions/electrons. After the reactivation of the precursor, the Li-ion batteries based on the recycled Fe2O3@CTs exhibits electrochemical performance with no decay compared to that of the devices based on the fresh products. This sustainable methodology, considering material abundance, eco-efficiency, synthetic approach and scalability, is of crucial importance to both academy and industry for achieving high-performance lithium-ion batteries.

Background: Circulating tumor cells (CTCs) are a burgeoning topic in cancer biomarker discovery research with minimal invasive blood draws. CTCs can be used as potential biomarkers for disease prognosis, early cancer diagnosis and pharmacodynamics. However, the extremely low abundance of CTCs limits their clinical utility because of technical challenges such as the isolation and subsequent detailed molecular and functional characterization of rare CTCs from patient blood samples. Methods: In this study, we present a novel density gradient centrifugation method employing biodegradable gelatin nanoparticles coated on silicon beads for the isolation, release, and downstream analysis of CTCs from colorectal and breast cancer patients. Results: Using clinical patient/spiked samples, we demonstrate that this method has significant CTC-capture efficiency (>80%) and purity (>85%), high CTC release efficiency (94%) and viability (92.5%). We also demonstrate the unparalleled robustness of our method in downstream CTC analyses such as the detection of PIK3CA mutations. Conclusion: The efficiency and versatility of the multifunctional density microbeads approach provides new opportunities for personalized cancer diagnostics and treatments.

We have demonstrate a facile strategy to achieve the controllable morphology transformation of TiO2 induced by the introduction of multi-walled carbon nanotubes. The intervention of functionalized carbon nanotubes (CNTs) is key to the formation of TiO2 nanopompons. Furthermore, the size of the obtained TiO2 nanopompons can be controlled by modulating the CNT amounts. The obtained TiO2 nanopompon-embedded CNT hybrid networks (TNP@CNT HNs) incorporate the advantages of hierarchical nanostructures and 3D interconnected conductive networks, including high surface area, uniform particle/pore size, short Li+ ion/electron transport pathway, and high electronic conductivity. These TNP@CNT HN-based anodes achieve a significant improvement in the insertion/extraction of Li+ ions and electrochemical performances via optimizing the CNT amounts and the size of the TiO2 nanopompons. The lithium-ion batteries based on the optimized TNP@CNT HNs exhibit excellent cycling stability (keeping approximately 200 mA h g−1 after 500 cycles at 2C rate, 1C = 170 mA g−1) and rate performance (approximately 125 mA h g−1 at 20C rate with a capacity retention of 77% after 2000 cycles).

We report here the antimicrobial ability of tetrabromobisphenol A (TBBPA) against Gram-positive bacteria without detectable resistance. Microscopy imaging and gene analysis reveal that the bacterial cell wall is the target of TBBPA. Structure-activity studies of TBBPA and its analogues relate the observed antimicrobial activity to the halogen substitution neighboring the phenolic hydroxyl group.

Tetrabromobisphenol A (TBBPA) is a brominated flame retardant with selective antimicrobial activity against Gram-positive bacteria. We show that TBBPA exerts bactericidal effects by damaging the cell wall and membrane of Staphylococcus aureus (SA) without inducing antimicrobial resistance. In vivo skin infection assays indicate that a low dose of TBBPA could contribute to wound closure and attenuate SA infection and inflammatory infiltration. TBBPA has potential for use as an antimicrobial agent against Gram-positive pathogens.

Three-dimensional LiNi 0.5 Mn 0.5 O 2 (3D-LiNi 0.5 Mn 0.5 O 2 ) nanostructures are in situ prepared using cryptomelane-type octahedral molecular sieve manganese dioxide (OMS-2) in the form of dendritic nanostructures as templates. The complete conversion of the OMS-2 precursor to layered α-NaFeO 2 -type LiNi 0.5 Mn 0.5 O 2 and the retention of the 3D dendritic nanostructures have been confirmed by XRD, FE-SEM, TEM, and HR-TEM. The as-synthesized nanostructured positive electrode exhibits a significant improvement in rate performance and cycling reversibility due to its unique nanostructures composed of single-crystalline LiNi 0.5 Mn 0.5 O 2 nanorods. And the influence of the assembly mode of nanosize LiNi 0.5 Mn 0.5 O 2 positive electrode material to its electrochemical performances has been investigated. The battery based on 3D-LiNi 0.5 Mn 0.5 O 2 retains a discharge capacity of 151.6 mAh g −1 (93% of the first discharge capacity) after 50 cycles. A specific discharge capacity of 141.8 mAh g −1 was retained at a rate of 3.2 C, which is about 80% of the capacity at a rate of 0.2 C.

The interaction between ZnO compact layer and TiCl 4 post-treatment on TiO 2 photoelectrode for dye sensitized solar cell (DSSC) is investigated. Photoelectrode combined the two modifications is designated as ZnO + 2l + TiCl 4 . It is found that after the TiCl 4 treatment the ZnO compact layer transforms to a bi-functional layer, which suppresses back electrons transfer from FTO to electrolyte and reduces the FTO/TiO 2 interfacial resistance. In addition, the newly formed TiO 2 coating generated by TiCl 4 post-treatment contains abundant and well dispersed Zn element, which further facilitates electron transfer at TiO 2 layer. Meanwhile, the electron lifetime in ZnO + 2l + TiCl 4 is the longest. Consequently, the overall energy conversion efficiency of the cell with ZnO + 2l + TiCl 4 is significantly enhanced to 8.9%, which is 8.8% higher than that with pure TiCl 4 post-treatment and 17.7% higher than that without any treatment. These results are verified by material characterization and corresponding opto-electrical properties measurements. Experimental results demonstrate this facile method is a more promising alternative to the conventional interface and surface modification in high efficient DSSCs.

A convenient way is experimented to reduce the amount of dye in quasi-solid DSSCs but raise open-circuit photovoltage and photocurrent density. AFM stereoscopic morphology and calculated roughness of root mean square indicates looser porous configuration is formed in the modified TiO 2 film which is beneficial for the penetration of quasi-solid electrolyte. Decreased content of sensitized dye is confirmed by UV–vis absorption spectra. Electrochemical impedance spectroscopy is employed to characterize the transport and recombination of electrons and also to assess the penetration of quasi-solid electrolyte in the porous matrix of DSSCs. Analysis of charge-transfer resistance and dc resistance of impedance of diffusion of tri-iodide reveals enhanced mobility of tri-iodide in DSSCs. Photovoltaic parameters of quasi-solid DSSCs show an increased open-circuit photovoltage due to the enlarged photoelectrode film porosity and the shift of redox level. Better penetration of quasi-solid electrolyte has a predominant advantage over the negative effect caused by lose of photocurrent, to some extent, as a result of decreased adsorbed dye. The best result of this beneficial outcome occurs when the PEG loading is 20%, giving an overall cell efficiency of 5.1%.

A novel and thin ZnO compact blocking film is employed at the interface of fluorine-doped tin oxide (FTO) substrate and mesoporous TiO2, and its influence on dye-sensitized solar cells (DSSCs) is investigated. The ZnO film prepared by spin-coating method on FTO is characterized by energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and UV–vis spectrophotometer. The ZnO film is firstly employed as an energy barrier between FTO and mesoporous TiO2 film in DSSCs, which improves open-circuit photovoltage (Voc) and fill factor (FF) with compensation of Jsc decrease, finally increasing energy conversion efficiency from 5.85% to 6.70%. Electrochemical impedance spectra (EIS) analysis and open-circuit voltage decay (OCVD) technique reveal that the existence of the energy barrier not only resulted in the effect of suppressing back electrons transfer from FTO to electrolyte but also blocking the electrons injection from the conductive band of TiO2 to FTO. The former effect effectively reduces the recombination which occurs in the region of FTO substrate, and the latter leads to remarkable increment of electron density in the TiO2, thus resulting in enhanced Voc and FF. These results suggest that the methodology of introducing the semiconductor with a more negative conduction band edge than TiO2 as the compact blocking film in DSSCs may be feasible.

We report two improved stability dye-sensitized TiO2 solar cells using poly (ethylene oxide)–poly (vinylidene fluoride) (PEO–PVDF) polymer-blend electrolytes modified with water and ethanol as hydroxyl-rich small-molecule additives. The effect of additive on the thermal property, viscosity, conductivity and the corresponding performance of the dye-sensitized solar cell (DSSC) were studied. After introducing the water and ethanol into the PEO–PVDF polymer-blend electrolytes, the conductivity is improved compared to that of the un-added electrolyte. This is due to the enhanced free ion concentration and ion transport channels in the electrolyte because of the cross-linking ability of these hydroxyl-rich additives. The increased ion concentration can be proved by the enhanced concentration of I− and I3− in the additive-modified electrolytes from UV–vis studies. The increased cross-linking network can be explained by the increased glass transition temperature (Tg) and viscosity of these additive-modified electrolytes from DSC and rheology studies. A more homogeneous morphology of ethanol-modified electrolyte from SEM study is used to further explain the better conductivity and stability of the cells based on these additive-modified electrolytes. From the evaluation of additive effect on the performance of the corresponding DSSC, we find that introducing water and ethanol leads to an increase in short-circuit photocurrent density (Jsc). This is due to the efficient transport of I−/I3− caused by enhanced I−/I3− concentration and increased ion transport channels in the electrolyte by adding additives. The best efficiency of 3.9% is achieved in the cell with ethanol-modified electrolyte.

A simple and efficient two-step method based on dispersive solid phase extraction (D-SPE) and dispersive liquid–liquid microextraction (DLLME) has been developed for the separation and preconcentration of 15 rare earth elements (REEs) from environmental water and sediment samples, followed by electrothermal vaporization-inductively coupled plasma mass spectrometry (ETV-ICP-MS) detection. With Chelex 100 as the adsorbent of D-SPE, target REEs were firstly extracted and the retained REEs were then desorbed by 0.1 mol L−1 HNO3. After 125 mmol L−1 Tris and 40 mmol L−1 1-phenyl-3-methyl-4-benzoylpyrazolone (PMBP) were added into the above elution solution, target REEs were further preconcentrated into CCl4 by DLLME. The developed dual extraction technique exhibited high enrichment factors (234 to 566-fold) and good anti-interference ability. Various parameters affecting the extraction of target REEs by D-SPE and DLLME were investigated in detail. Under the optimal conditions, the limits of detection (LODs, 3σ) for target REEs were in the range of 0.003–0.073 ng L−1 with the relative standard deviations (CY,La,Ce,Pr,Nd,Gd,Dy = 1.0 ng L−1, CSm,Eu,Tb,Ho,Er,Tm,Yb,Lu = 0.2 ng L−1, n = 7) ranging from 6.7 to 11.5%. The proposed method of D-SPE-DLLME-ETV-ICP-MS was successfully applied to the determination of 15 REEs in water and sediment samples with the recoveries of 78–115% and 75–117% for the spiked water and sediment samples, respectively. To validate the accuracy of the method, a Certified Reference Material of GBW07301a stream sediment was analyzed and the determined values were in good agreement with the certified values.