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Early cancer diagnosis requires ultrasensitive detection of tumor markers in blood. To this end, we develop a novel microcantilever immunosensor using nanobodies (Nbs) as receptors. As the smallest antibody (Ab) entity comprising an intact antigen-binding site, Nbs achieve dense receptor layers and short distances between antigen-binding regions and sensor surfaces, which significantly elevate the generation and transmission of surface stress. Owing to the inherent thiol group at the C-terminus, Nbs are covalently immobilized on microcantilever surfaces in directed orientation via one-step reaction, which further enhances the stress generation. For microcantilever-based nanomechanical sensor, these advantages dramatically increase the sensor sensitivity. Thus, Nb-functionalized microcantilevers can detect picomolar concentrations of tumor markers with three orders of magnitude higher sensitivity, when compared with conventional Ab-functionalized microcantilevers. This proof-of-concept study demonstrates an ultrasensitive, label-free, rapid, and low-cost method for tumor marker detection. Moreover, interestingly, we find Nb inactivation on sensor interfaces when using macromolecule blocking reagents. The adsorption-induced inactivation is presumably caused by the change of interfacial properties, due to binding site occlusion upon complex coimmobilization formations. Our findings are generalized to any coimmobilization methodology for Nbs and, thus, for the construction of high-performance immuno-surfaces. Electronic Supplementary Material Supplementary material (experimental section, HER2 detection using anti-HER2-mAb-functionalized microcantilevers) is available in the online version of this article at 10.1007/s12274-021-3588-4.

Water oxidation to molecular oxygen is indispensable but a challenge for splitting H2O. In this work, a series of Co-based metal-organic cages (MOCs) for photoinduced water oxidation were prepared. MOC-1 with both bis(μ-oxo) bridged dicobalt and Co-O (O from H2O) displays catalytic activity with an initial oxygen evolution rate of 80.4 mmol/g/h and a TOF of 7.49 × 10-3 s-1 in 10 min. In contrast, MOC-2 containing only Co-O (O from H2O) in the structure results in a lower oxygen evolution rate (40.8 mmol/g/h, 4.78 × 10-3 s-1), while the amount of oxygen evolved from the solution of MOC-4 without both active sites is undetectable. Isotope experiments with or without H218O as the reactant successfully demonstrate that the molecular oxygen was produced from water oxidation. Photophysical and electrochemical studies reveal that photoinduced water oxidation initializes via electron transfer from the excited [Ru(bpy)3]2+* to Na2S2O8, and then, the cobalt active sites further donate electrons to the oxidized [Ru(bpy)3]3+ to drive water oxidation. This proof-of-concept study indicates that MOCs can work as potential efficient catalysts for photoinduced water oxidation.

The arity of convex spaces is a numerical feature which shows the ability of finite subsets spanning to the whole space via the hull operators. This paper gives it a formal and strict definition by introducing the truncation of convex spaces. The relations that between the arity of quotient spaces and the original spaces, that between the arity of subspaces and superspaces, that between the arity of product spaces and factors spaces, and that between the arity of disjoint sums and term spaces, are systematically studied. A mistake of a formula in [M. Van De Vel, Theory of Convex Structures, North-Holland, Amsterdam, 1993] is corrected. It is shown that a convex space is Alexandrov iff its arity is 1. The convex structures with arity ≤n are equivalent to structured sets with n-restricted hull operators.

Accelerated life testing (ALT) is typically used to assess the reliability of material's lifetime under desired stress levels. Recent advances in material engineering have made a variety of material alternatives readily available. To identify the most reliable material setting with efficient experimental design, a sequential test planning strategy is preferred. To guarantee a tractable statistical mechanism for information collection and update, we develop explicit model parameter update formulas via approximate Bayesian inference. Theories show that our explicit update formulas give consistent parameter estimates. Simulation study and a case study show that the proposed sequential selection approach can significantly improve the probability of identifying the material alternative with best reliability performance over other design approaches.

The Convention on Biological Diversity and the United Nations Framework Convention on Climate Change are the two most important environmental conventions for biodiversity conservation and climate change mitigation. Both conventions have carried out a variety of work and established a joint working group to promote synergy. This study reviews the cooperation process between both conventions, and identifies the gaps in the synergistic mechanism by analyzing the status of implementation in China. The following problems in China were found to be associated with convention implementation: 1) shortage of coordination among implementing organization; 2) the existing strategic plans lack planning for synergistic implementation; 3) the monitoring system lacks coordination management, thus making the sharing of monitoring results among each unit challenging; and 4) information sharing from partner ministries is inadequate. Combining the status of China’s implementation and the experience of other contracting parties, the following strategies are proposed: 1) a synergistic implementation mechanism should be established at the national level; 2) a national strategic plan should be developed for synergistic implementation; 3) a monitoring system and management mechanism should be developed that comprehensively consider the monitoring indicators of each convention; and 4) an implementation information-sharing platform should be built.

The North Jiangsu Basin (NJB), located in the western part of the North Jiangsu-South Yellow Sea Basin, is a critical region providing invaluable archives about the evolution processes of the land-ocean interchange and climatic environments in a coastal zone. Chronology is of crucial importance to reconstruct the timing of sea-level eustacy, and shoreline changes, as well as the evolution of the regional environment by means of numerical dating to determine the age of sedimentary strata in the sea–land interaction zone of the NJB. However, sediment dating in the NJB remains controversial due to limitations in the quantity and quality of chronological data. Therefore, the sediments in the Jianhu Gangxi (GX) profile of the NJB were analyzed in this study by applying both fine-grained quartz optically stimulated luminescence (OSL) dating and 14C dating. The results were used to discuss the processes of regional environment evolution. The OSL dating of fine-grained quartz components in sediments was found to be a reliable method to determine deposition ages of sediments in the land-sea interaction zone in the NJB. The combination of OSL and accelerator mass spectrometry 14C dating techniques allowed a reliable and high-resolution chronological framework for the GX profile. Since the last glaciation, the sedimentary environment in the eastern portion of the NJB changed significantly. In particular: (1) between 13 and 7.25 ka B.P, the area of interest was dominated by lacustrine deposition within a stable sedimentary environment with low deposition rates; (2) from 7.25 to 6.45 ka B.P, marine transgression events occurred, and the deposition rate increased rapidly in an area of land-sea interaction; (3) after 6.45 ka B.P, a regression event occurred, and the study area transformed into a lowland lake environment.

The industrial sector is the backbone of China's national economy. The industrial carbon emission efficiency (ICEE) of China is directly related to the achievement of carbon emission reduction targets. This paper reports on the use of the minimum distance (min-SBM) method to determine the ICEE of 30 provinces in China during 1998-2015, as well as the use of a spatial econometric method to investigate the convergence and influencing factors of the regional ICEE. The results indicate significant regional differences in the ICEE. The provinces with higher average values of ICEE are located in the eastern coastal areas, whereas the provinces with lower average values of ICEE are located in the central and western inland regions. The results of the spatial autocorrelation index reveal that China's inter-provincial ICEE exhibits significant spatial autocorrelation characteristics, and its spatial distribution demonstrates a certain regularity. The local indicators of spatial association diagram further illustrate that most provinces in China have high and low agglomeration values. With the introduction of the spatial effect, the absolute and conditional convergence rates increase. In addition to the non-significant industrial structure effect, the level of economic development, foreign direct investment, technological progress, and government intervention demonstrate a positive impact on the ICEE convergence, whereas the energy consumption structure has a negative impact. This work investigates the cause for the regional gap in China's current ICEE. Suggestions for improving the efficiency of China's industrial carbon emissions and narrowing the regional gap are provided, which serve as a reference value for China to achieve the peak of carbon dioxide emissions before 2030.

A novel oilfield high-oil-recovery water injection treatment device, the hydrocyclone oil removal device, was developed to treat oilfield sewage in the oil phase. It addresses the problems of high oil content in oilfield sewage, direct discharge of contaminants to the environment, and reduction of formation water absorption capacity by reinjection formation. An experimental verification and numerical simulation of the device were carried out to analyze its mechanism and influencing factors. An analysis of the flow path, phase distribution, velocity distribution, and pressure distribution of oil and water revealed the oil removal mechanism of the hydrocyclone oil removal device: automatic separation of oil and water could be realized by using the physical properties of the fluid, the special structure of the equipment, and the appropriate operating parameters. The influence of the inlet oil concentration, flow, pressure, and oil droplet size on the separation efficiency was investigated. The inlet flow, pressure, and the oil droplet size were found to be directly proportional to the separation efficiency, and the oil concentration was found to be inversely proportional to the separation efficiency. These results could further the efficient application of the high-oil-recovery water injection treatment device. The research results also have important engineering value for the efficient treatment and recycling of oil and gas field wastewater.

Flumioxan was used to control annual broad-leaved and dicotyledonous weeds. Considering the limited information available, comprehensive investigation of persistence and mobility of flumioxazin in Chinese soil is very important. The degradation, adsorption-desorption, mobility, and leaching risk of flumioxazin in four Chinese soils were investigated under laboratory conditions. The degradation rates of flumioxazin, which correlated with soil moisture, microorganisms, organic matter and pH, were 8.2−50.6 days in the four soils under different conditions. Microorganisms influenced these rates greatly, with half-lives increasing 1.67−2.39-fold. Three possible metabolites were detected by ultrahigh-performance liquid chromatography with high-resolution mass spectrometry, and the metabolic pathways were cleavage of the imide and amide linkages and opening of the cyclic imide. The adsorption capacity of flumioxazin in soil was strongly positively correlated with the soil’s cation exchange capacity (CEC) and organic matter (OM) content, which had correlation coefficients > 0.83. Negative and positive desorption hysteresis effects were observed in Guizhou soil and the other three soils, respectively, which might be related to the different soil constitutions. The mobility was relatively weak in the four Chinese soils and negatively related to CEC and OM content, with correlation coefficients > 0.86. Moreover, the leaching risk of flumioxazin was uncertain for the underground water. The results indicated that flumioxazin was a low-risk herbicide and could be used to evaluate the environmental fate and risk of flumioxazin in soil.

Recurrent pregnancy loss (RPL) refers to two or more consecutive spontaneous abortion before 24 weeks of gestation, representing 1% of couples of childbearing age. Epigenetic factors including dysregulation of DNA methylation of some genes may play a role in RPL. To identify RPL related genes modulated by DNA methylation expressed in decidua and blood. Three decidua samples each from RPL patients and normal controls were recruited to perform genome-wide bisulfite sequencing (GWBS) and transcriptome sequencing. Based on the above results, 22.52 kb of differential methylation regions (DMRs) from 17 genes were verified by bisulfite sequencing PCR at specific region (Hi-MethylSeq) in another 15 decidua (7RPL vs. 8 Controls) and 13 blood (5RPL vs. 8 Controls) samples. 23 genes showed significantly differential cytosine methylation status and distinct expression level between PRL patients and healthy controls synergistically. Three signaling pathways were found to be shared between genes with both hypomethylated differential methylation regions (DMR) and upregulated differential gene expression (DGE). The results from Hi-MethylSeq showed that the hypermethylation of SGK1 in both blood and decidua samples in RPL patients, which was consistent to its lower expression in endometrium reported earlier. SGK3 and CREB5 also showed modulated methylation level in RPL decidua. Our finding supported that aberrant methylation of SGK1 and CREB5 could be a cause of the dysregulation of these gens in the endometrium, which is one of cause of reproductive failure. The function of SGK3 in reproduction system deserves further investigation.

YVO4:Yb3+:Er3+ nanoparticles and their mixture with Au nanoparticles have been fabricated by a simple chemical method. With the excitation of a 975-nm laser, both samples had strong upconversion emissions at 2.18, 2.25, and 2.36 eV, which correspond to the transitions 4F9/2 → 4I15/2, 4S3/2 → 4I15/2 and 2H11/2 → 4I15/2 of Er3+ ions, while the emission at 2.36 eV has a large overlap with the resonant absorption energy, 2.34 eV, of the Au nanoparticles. With the coupling of the Au nanoparticles, the upconversion emission at 2.36 eV presents a strong quenching effect which is due to the energy transfer from the Er3+ ions to the Au nanoparticles. This depends on the energy difference between the emission of the Er3+ ions and the absorption of the Au nanoparticles. The upconversion power dependence shows that the slope factor of the power dependence is about 3 for a high pump power, which means that the upconversion process is a three-photon process for both samples.

Although immunotherapy is emerging as a revolutionary strategy for cancer therapy, its clinical effect is severely impaired by adaptive immune evasion and inefficient activation of antitumor immune response. Photodynamic therapy and chemotherapy have been shown to efficiently enhance the therapeutic effect of PD-L1 immunotherapy via different mechanisms. However, the lack of a precise drug delivery system seriously impedes the clinical application of combination therapy. To address these restrictions, a matrix metalloproteinases-2 (MMP2)-activated shrinkable nanosystem was developed to potentiate the antitumor efficacy of anti-PD-L1 antibody (aPDL1) delivered along with a chemo-photodynamic therapy. The nanosystem maintains its structure to accelerate tumor accumulation and shrinks down to a smaller size to facilitate tumor penetration and cellular uptake upon arriving in the tumor microenvironment. The exposure of aPDL1 on the surface of the biodegradable mesoporous silica cores (bMSNs) blocks the PD-1/PD-L1 interaction between tumor cells and T cells. Meanwhile, photosensitizer chlorin e6 (Ce6) and paclitaxel (PTX) loaded bMSNs effectively enter tumor cells and induce chemo-photodynamic therapy. The nanosystem elicits a chemo-photodynamic-induced immune response and improves the therapeutic effect of PD-L1 blockade mediated by aPDL1. Furthermore, the nanosystem displays a sustained prohibitive effect on tumor metastasis to distant sites. Our work presents a promising strategy for enhancing the efficacy of cancer immunotherapy.

Aqueous-based Zn–air and Al–air batteries are considered to be promising post-lithium energy storage technologies owing to their safety, environmental friendliness, affordability, and high energy density. Nevertheless, traditional liquid Zn–air and Al–air batteries have problems such as volatilization and leakage, as well as the realization of miniaturized, portable, and wearable electronic devices. The practice of optimizing the battery structure by replacing the flowing electrolyte with a solid type has emerged and made significant progress in the past ten years. Herein, this review provides a guiding and comprehensive summary of the basic understanding and manufacturing ideas of the solid electrolyte for Zn–air and Al–air batteries. First, two types of alkaline solid electrolytes are distinguished, including alkaline anion exchange membranes (AAEMs) and gel polymer electrolytes (GPEs). Then, three sorts of major framework materials (i.e., artificial organic polymer, biomass materials, and inorganic materials) are reviewed and discussed. Most importantly, the latest research progress and improvement strategies to enhance the electrolyte membrane performances involving conductivity, mechanical properties, and electrochemical stability are also highlighted. Finally, challenges and prospects for the future development of alkaline solid electrolytes are emphasized.

Wearing surgical masks is one of the best protective measures to protect humans from viral invasion during the 2019 coronavirus (COVID-19) outbreak. However, wearing surgical masks for extended periods will cause uncomfortable sweltering sense to users and are easy to breed bacteria. Here, we reported a novel fibrous membrane with outstanding comfortability and antibacterial activity prepared by PP ultrafine fiber nonwovens and antibacterial functionalized h-BN nanoparticles (QAC/h-BN). The thermal conductivity of commercial PP nonwovens was only 0.13 W m-1 K-1, but that of the QAC/h-BN/PP nanocomposite fibrous membranes can reach 0.88 W m-1 K-1, an enhancement of 706.5% than commercial PP nonwovens. The surface temperature of commercial PP surgical masks was 31.8 °C when the wearing time was 60 min. In contrast, QAC/h-BN/PP surgical masks can reach 33.6 °C at the same tested time, exhibiting stronger heat dissipation than commercial PP surgical masks. Besides, the antibacterial rates of QAC/h-BN/PP nanocomposite fibrous membranes were 99.3% for E. coli and 96.1% for S. aureus, and their antibacterial mechanism was based on "contact killing" without the release of unfavorable biocides. We think that the QAC/h-BN/PP nanocomposite fibrous membranes could provide better protection to people.

The optimization of back contact interface is crucial to improve the performance of Cu2ZnSnS4 (CZTS) thin film solar cells. In this paper, we first employ Al-doped ZnO (AZO) as the intermediate layer into the Mo/CZTS interface to improve the quality of back contact region. This AZO intermediate layer, obtained from the sputtering method prior to the CZTS precursor deposition, initially blocks the direct contact of CZTS with the Mo layer and thus indeed suppresses the decomposition reaction between Mo and CZTS. Consequently, the generation of voids at the back contact region is obviously avoided. Besides, the AZO intermediate layer can inhibit the reaction between sulfur (S) and Mo during sulfurization process, and thus significantly reduce the thickness of MoS2. Meanwhile, the AZO intermediate layer with suitable thickness does not affect the crystal quality of CZTS absorber layer. Moreover, the effects of different thicknesses of predeposited AZO on the film morphology, composition, and corresponding device performance were systematically studied. After optimizing the thickness of the AZO layer, the efficiency of the resultant device has increased from 7.1% to 8.4% (the active area efficiency is 9.2%).

One-dimensional nanomaterials including cellulose nanocrystals (CNCs) and gold nanorods (GNRs) are widely used in optical materials due to their respective inherent features: birefringence with accompanying light retardation and surface plasmon resonance (SPR). Herein, we successfully combine these properties of both nanorods to generate synergistic and readily tunable structural colors in hybrid composite polymer films. CNCs and GNRs are embedded either in the same or in separate films after unidirectional alignment in dynamic hydrogels. By synergistically leveraging CNCs and GNRs with diverse amounts in hybrid films or stacked separate films, wide-ranging structural colors are obtained, far beyond those from films solely with aligned CNCs or GNRs. Higher GNR contents enhance light absorption at 520 nm with promoted magenta colors, while more CNCs affect the overall phase retardation with light absorption between 400 and 700 nm between crossed polarizers. Moreover, adjusting the angles between films solely with CNCs or GNRs

Carboxylic-acid-initiated ring-opening polymerization (ROP) of epoxides is a fast approach to esterified polyethers which are cleavable at the termini or centers. A major challenge lies in conventional ROP methods because of the lability of ester groups formed in the initiation step. Here, we describe chemoselective ROP of epoxides from aliphatic, aromatic, and methacrylic carboxylic acids using two-component metal-free catalysts. Transesterification is clearly absent so that well-defined α-(carboxylic ester)-ω-hydroxy polyethers are generated in one step from monocarboxylic acids. The livingness of the ROP is verified despite the slow initiation mode. The ester end group can be readily cleaved from the polyether hydrolytically. An α,ω-dihydroxy poly(propylene oxide) with two central ester groups is generated from a diacid initiator and transformed

The title compound C19H17F3N6 was synthesized and structurally characterized by infrared and mass spectroscopy, 1H NMR, elemental analyses and single crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 17.097(4) A, b = 7.1668(16) A, c = 18.389(3) A, β = 118.251(15)°, V = 1984.8(8) A3, Z = 4, Dc = 1.293 g cm–3, F(000) = 800, μ(MoKα) = 0.10 mm–1, R1 = 0.0667, and wR2 = 0.2084 for reflections with I > 2σ(I). Pyrazolo[1,5-a]pyrimidine and phenyl ring are almost coplanar, and the piperazine ring is in a chair conformation. The crystal structure is stabilized by C–H⋅⋅⋅N hydrogen interactions and a number of weak π⋅⋅⋅π interactions. In addition, the results of the determination of biological activity showed that the compound exhibited significant inhibitory activity against K562 and MKN45 cancer cell lines.

Phenylboronic acid-functionalized nanometer-sized CaCO3 particles (PBA-CaCO3) were designed to determine the carcinoembryonic antigen (CEA) glycoprotein with a portable Ca2+ ion-selective electrode (Ca-ISE) through a typical boronate ester bond. CaCO3 nanospheres were conjugated to 3-aminophenylboronic acid by amine-epoxy reaction, whereas target CEA was captured into the aptasensing interface by the immobilized thiolated aptamer on gold substrate. Upon PBA-CaCO3 introduction, 3-aminophenylboronic acid labeled to CaCO3 microsphere specifically recognized with CEA glycoprotein based on sugar-boronic acid interaction to form a sandwiched complex. The carried CaCO3 was dissolved under acidic conditions to release Ca2+ ion with a portable Ca-ISE readout. Thanks to the specific boronate ester bond between PBA and 1,2-diols, the synthesized PBA-CaCO3 exhibited good conjugation properties for CEA glycoprotein. Under optimum conditions, Ca-ISE-based aptasensing platform exhibited good electrode potential response for evaluation of target CEA, and allowed detection of CEA at a concentration as low as 7.3 pg mL-1. Importantly, Ca-ISE-based aptasensing system is readily extended to detect other disease-related glycoproteins by controlling the corresponding aptamer.

A series of (trifluoromethyl)cyclopropanes (TFCPs) tolerating a broad range of functional groups, known as tert-butyl bioisosteres, have been obtained from the cyclization reaction between nitromethane­ and 5-[β-(trifluoromethyl)styryl]isoxazoles in 70–94% yields and 75:25 to 90:10 dr. This method offers practical access to this cyclopropyl moiety of pharmacological interest, employing an inorganic base under phase-transfer conditions.

Fiber-based sensors are desirable to provide an immersive experience for users in the human-computer interface. We report a hierarchically porous silver nanowire-bacterial cellulose fiber that can be utilized for sensitive detection of both pressure and proximity of human fingers. The conductive fiber was synthesized

The oxidation of benzaldehyde (A1CHO) at atmospheric pressure in a jet-stirred reactor at equivalence ratios of 0.4 and 2.0 within 475–900 K was studied. The intermediates and products were identified by synchrotron radiation photoionization and molecular beam mass spectrometry. Compared with previous studies, 29 species such as HCHO, CH3O, H2O2, ketene, furan, 2,4-cyclopentadiene-1-one (C5H4O), furfural, o-benzoquinone, 1,4-benzenediol and 1,4-cyclohex-2-enedione were newly detected. A kinetic model, involving 376 species and 2163 reactions was proposed, which reasonably predicted the experimental value. Rate-of-production analysis shows that H-abstractions reactions involving H atoms, OH, CH3, HO2 and phenoxy radicals dominate the consumption of A1CHO. The decarbonylation reactions and ring opening reactions have a certain contribution to the promotion of oxidation process. Phenoxy radicals, phenol and C5H4O are one of the most significant intermediates for A1CHO oxidation. Sensitivity analysis shows that A1CHO+OH=A1CO+H2O and H2O2(+M) =OH+OH(+M) are among the most sensitive reactions to promote the consumption of A1CHO at both conditions while the reaction A1OH+O2=A1O+HO2 has strong inhibiting effect. A1CHO is more difficult to produce benzene compared with benzyl alcohol oxidation while is easier to generate phenol at the same condition. These results will enrich the understanding the oxidation mechanism and soot formation of A1CHO as a potential aromatic fuel.

Enhancing anode performance is a critical step to improving the power output and energy storage of microbial fuel cells (MFCs). In this study, MFCs containing pseudocapacitive anode materials, such as polypyrrole-carboxymethyl cellulose (PPy-CMC) composite films, were used to coat the nitrogen-doped carbon nanotube (N-CNT)/sponge (S) for use in MFCs. The capacitive anode could function as a bioanode, store electrons generated from the microbial oxidation of a substrate, and release the accumulated charge as needed. Scanning electron microscopy results indicated that the composite anode had a three-dimensional macroporous structure with a large specific surface area, providing more sites for microbial attachment and growth. Experimental results showed that MFCs equipped with PPy-CMC/N-CNT/S capacitive bioanodes had a maximum power density of 4.88 W m−3, which was 1.34 and 1.71 times as much as those of PPy/N-CNT/S and N-CNT/S bioanodes (3.65 and 2.85 W m−3), respectively. Moreover, the charge–discharge time of 60–90 min, the total charge Qm of the MFC equipped with the PPy-CMC/N-CNT/S anode was the largest (5154.08 mC cm−2)—5.7 times higher than that of the N-CNT/S anode. The excellent performance of the MFC equipped with the PPy-CMC/N-CNT/S anode was attributable to the composite materials, which exhibited a large-pore structure, good biocompatibility, large capacitance, and high specific surface area. Therefore, this synthesized composite exhibited potential as a capacitive and biocompatible anode material in MFCs.

ConspectusGold (Au), a transition metal with an atomic number of 79 in the periodic table of elements, was discovered in approximately 3000 B.C. Due to the ultrahigh chemical stability and brilliant golden color, Au had long been thought to be a most inert material and was widely utilized in art, jewelry, and finance. However, it has been found that Au becomes exceptionally active as a catalyst when its size shrinks to the nanometer scale. With continuous efforts toward the exploration of catalytic applications over the past decades, Au nanomaterials show critical importance in many catalytic processes. Besides catalysis, Au nanomaterials also possess other promising applications in plasmonics, sensing, biology and medicine, due to their unique localized surface plasmon resonance, intriguing biocompatibility, and superior stability. Unfortunately, the practical applications of Au nanomaterials could be limited because of the scarce reserves and high price of Au. Therefore, it is quite essential to further explore novel physicochemical properties and functions of Au nanomaterials so as to enhance their performance in different types of applications.Recently, phase engineering of nanomaterials (PEN), which involves the rearrangement of atoms in the unit cell, has emerged as a fantastic and effective strategy to adjust the intrinsic physicochemical properties of nanomaterials. In this Account, we give an overview of the recent progress on crystal phase control of Au nanomaterials using wet-chemical synthesis. Starting from a brief introduction of the research background, we first describe the development history of wet-chemical synthesis of Au nanomaterials and especially emphasize the key research findings. Subsequently, we introduce the typical Au nanomaterials with untraditional crystal phases and heterophases that have been observed, such as 2H, 4H, body-centered phases, and crystal-phase heterostructures. Importantly, crystal phase control of Au nanomaterials by wet-chemical synthesis is systematically described. After that, we highlight the importance of crystal phase control in Au nanomaterials by demonstrating the remarkable effect of crystal phases on their physicochemical properties (e.g., electronic and optical properties) and potential applications (e.g., catalysis). Finally, after a concise summary of recent advances in this emerging research field, some personal perspectives are provided on the challenges, opportunities, and research directions in the future.

In the exploitation process of offshore natural gas hydrate (“hydrate” for short), it is necessary to take into consideration the wear of wellbore equipment caused by micron-sized sand particles after their breaking through the sand control facility of the wellbore. At present, however, there is no literature on the migration, deposition and blockage of micron-sized sand particles (

Ethylene plays a critical regulatory role in climacteric fruit ripening, and its biosynthesis is fine-tuned at the transcriptional and posttranslational levels. Nevertheless, the mechanistic link between transcriptional and posttranslational regulation of ethylene biosynthesis during fruit ripening is largely unknown. This study uncovers a coordinated transcriptional and posttranslational mechanism of controlling ethylene biosynthesis during banana (Musa acuminata) fruit ripening. NAC (NAM, ATAF, and CUC) proteins MaNAC1 and MaNAC2 repress the expression of MaERF11, a protein previously known to negatively regulate ethylene biosynthesis genes MaACS1 and MaACO1. A RING E3 ligase MaXB3 interacts with MaNAC2 to promote its ubiquitination and degradation, leading to the inhibition of MaNAC2-mediated transcriptional repression. In addition, MaXB3 also targets MaACS1 and MaACO1 for proteasome degradation. Further evidence supporting the role of MaXB3 is provided by its transient and ectopic overexpression in banana fruit and tomato (Solanum lycopersicum), respectively, which delays fruit ripening via repressing ethylene biosynthesis and thus ethylene response. Strikingly, MaNAC1 and MaNAC2 directly repress MaXB3 expression, suggesting a feedback regulatory mechanism that maintains a balance of MaNAC2, MaACS1, and MaACO1 levels. Collectively, our findings establish a multilayered regulatory cascade involving MaXB3, MaNACs, MaERF11, and MaACS1/MaACO1 that controls ethylene biosynthesis during climacteric ripening.

The crystal phase-based heterostructures of noble metal nanomaterials are of great research interest for various applications, such as plasmonics and catalysis. However, the synthesis of unusual crystal phases of noble metals still remains a great challenge, making the construction of heterophase noble metal nanostructures difficult. Here, we report a one-pot wet-chemical synthesis of well-defined heterophase fcc-2H-fcc gold nanorods (fcc: face-centred cubic; 2H: hexagonal close-packed with stacking sequence of “AB”) at mild conditions. Single particle-level experiments and theoretical investigations reveal that the heterophase gold nanorods demonstrate a distinct optical property compared to that of the conventional fcc gold nanorods. Moreover, the heterophase gold nanorods possess superior electrocatalytic activity for the carbon dioxide reduction reaction over their fcc counterparts under ambient conditions. First-principles calculations suggest that the boosted catalytic performance stems from the energetically favourable adsorption of reaction intermediates, endowed by the unique heterophase characteristic of gold nanorods., The crystal phase-based heterostructures of noble metal nanomaterials are of interest for various applications. Here, the authors report the wet-chemical synthesis of gold nanorods with a well-defined fcc-2H-fcc heterophase, which possess unique optical and catalytic properties.

The conversion efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells is relatively low, due to the complicated intrinsic defects and the unsuitable contact interfaces. In this work, MoO2 thin films prepared by a simple preannealing method are introduced to Mo/CZTSSe back contact interface. For the first time, it is found that MoO2 acts as a sacrificial layer rather than the traditional intermediate layer. Specifically, the MoO2 sacrificial layer will disappear and become a thin MoSe2 layer after it blocks the over-selenization of Mo electrode. In addition, it has a positive effect on the preferred orientation of MoSe2 and the crystallization of CZTSSe layer. Furthermore, the chemical mechanism on MoO2 as sacrificial layer is first investigated, and it can be well described by Van ’t Hoff equation. With the aid of MoO2 sacrificial layer, the performance of CZTSSe device increases from 5.67% to 8.29% (active area efficiency is 9.08%) without the MgF2 antireflection layer.

In recent years, microbial fuel cell (MFC) has been regarded as a promising technology for dye wastewater treatment. Compared with traditional anaerobic reactors, MFC has better decolorization effect while producing electricity simultaneously. In this paper, a double-chamber MFC with the sponge anode modified by polyaniline and chitosan-NCNTs was employed for simultaneous azo dye decolorization and bioelectricity generation. The influence of dye concentration, co-substrate concentration, and operating temperature on the performance of MFC with the modified anodes were studied. The results showed that a high decolorization efficiency (98.41%) and maximum power density (2816.67 mW m-3) of MFC equipped with modified bioanodes were achieved due to the biocompatibility and bioelectrocatalysis of modified material. And the biomass on the modified anode's surface was increased by 1.47 times. Additionally, microbial community analysis revealed that the modification of polyaniline and chitosan-NCNTs improved the selective enrichment of specific communities and the main microorganism was the electroactive and decolorizing bacteria Enterobacter (62.84%). Therefore, the composite anode is capable of fully utilizing the synergistic role of various materials, leading to superior performance of dye decolorization in MFCs. This work provided a strategy for the research on the recovery of biomass energy and decolorization in wastewater treatment. Graphical Abstract.

Summary Two-dimensional (2D) nanomaterials have attracted increasing interest because of their compelling physicochemical properties and promising applications. Recent studies have demonstrated that phases of nanomaterials could significantly affect their properties and applications because of the distinct atomic arrangements. Besides crystalline phases, the amorphous nanomaterials, which lack long-range atomic ordering, and heterophase nanostructures consisting of more than one phase have also shown enhanced performances in some specific applications. Recently, with the rapid development in phase engineering of nanomaterials (PEN), the controlled synthesis of 2D nanomaterials with unconventional phases and the exploration of phase-dependent properties and applications have been witnessed. In this perspective, we briefly summarize the research progress on 2D nanomaterials with unconventional phases, including unconventional crystal phases, amorphous phase, and heterophase. On the basis of different material categories, we highlight their synthetic methodologies, unique structures, and intriguing properties. Finally, we provide personal insights on challenges and potential research opportunities in this emerging field.

For diffusion processes, we extend various two-sided exit identities to the situation when the process is only observed at arrival times of an independent Poisson process. The results are expressed in terms of solutions to the differential equations associated with the diffusions generators.

Crystal phase can greatly affect the physicochemical properties and applications of nanomaterials. However, it still remains a great challenge to synthesize nanostructures with the same composition and morphology but different phases in order to explore the phase-dependent properties and applications. Herein, we report the crystal phase-controlled synthesis of PtCu alloy shells on 4H Au nanoribbons (NRBs), referred to as 4H-Au NRBs, to form the 4H-Au@PtCu core-shell NRBs. By tuning the thickness of PtCu, 4H-PtCu and face-centered cubic (fcc) phase PtCu (fcc-PtCu) alloy shells are successfully grown on the 4H-Au NRB cores. This thickness-dependent phase-controlled growth strategy can also be used to grow PtCo alloys with 4H or fcc phase on 4H-Au NRBs. Significantly, when used as electrocatalysts for the ethanol oxidation reaction (EOR) in alkaline media, the 4H-Au@4H-PtCu NRBs show much better EOR performance than the 4H-Au@fcc-PtCu NRBs, and both of them possess superior performance compared to the commercial Pt black. Our study provides a strategy on phase-controlled synthesis of nanomaterials used for crystal phase-dependent applications.

Carbon (C) and nitrogen (N) represent the commonest limiting nutrients for microbial growth in terrestrial ecosystems. However, most of our understanding of how C:N ratios modulate microbial growth comes from short-term growth assays under controlled conditions. Four levels of N additions including control (CK, 0 kg·hm− 2·a− 1), low N (LN, 50 kg·hm− 2·a− 1), medium N (MN, 100 kg·hm− 2·a− 1), and high N (HN, 150 kg·hm− 2·a− 1) inputs were applied monthly in a pine forest (Pinus tabulaeformis). Three C management practices were further conducted in each N additions plot, namely aboveground litter and belowground root removal (LRR), aboveground litter removal (LR), and intact soils (non-removal, NR). Soil bacterial richness, diversity, community composition and soil properties were measured. MN and HN significantly increased the relative abundance of copiotrophic taxa, but decreased that of oligotrophic taxa. Bacterial richness and diversity were not altered by N enrichment. LRR significantly increased the relative abundance of Gemmatimonadetes while decreased that of Actinobacteria. C management did not affect bacterial richness and community structure but LR significantly decreased bacterial diversity. Structural equation modeling showed that N addition induced the decrease in soil pH was responsible for the changes in the bacterial community structure. C management exhibited a direct negative effect on bacterial diversity and had an indirect positive effect on it via increasing soil moisture and microbial biomass C:N ratio. The findings highlight the contrasting impacts of N addition and C management on soil bacterial communities and emphasize the regulation of above- and below-ground C substrate supplies on the N responses of soil bacterial communities.

A method to determine the volatile organic compounds (VOCs) in the recycled polyethylene terephthalate fiber was presented by using the headspace sampling-gas chromatography coupled to flame ionization detector (HS-GC-FID), in order to evaluate the level of VOC contamination. The extraction variables, such as the incubation temperature, the pre-incubation time and the size of the vial, were also studied. The effects on the determination of VOC were also compared using two type chromatographic columns. The optimal conditions were found using a headspace sampling for 20 min at 100 °C, where 120 mL vials and TM-1 column were prior to analysis of benzene compounds in PET(polyethylene terephthalate) fibers. The results can be used in analysis of VOC from recycled PET fibers.

As consumer awareness of heavy metal content in textile increased, it is necessary to develop analytical methods that identify and quantify heavy metals. In order to comprehensively investigate the potential risks of antimony (Sb) in recycled polyester fiber to humans health, this study developed acid digestion method, with the condition that the volume ratio of concentrated sulfuric acid to hydrogen peroxide was 1, and digested at 200°Cfor 1.5h, which produced clear and colorless solutions.Currently, microwave and dry ashing are also common methods for digesting polyethylene terephthalate samples. Three pretreatment methods for determining the content of Sb in recycled polyester fibers was evaluated. Results showed that inductively coupled plasma-optical emission spectrometry (ICP-OES) analysis of acid digested recycled polyester samples resulted in Sb content higher than for the microwave and dry ashing digestion methods which incompletely digest recycled polyester. Moreover, compared with microwave digestion and dry ashing, acid digestion had a low detection limit of 0.0116 ug/mL, a high spike recovery of 82% to 106% and the RSD value less than 2%, which indicates that the data was accurate and reproducible. Therefore, in this study, acid digestion - ICP-OES was an effective method for detecting the content of heavy metal Sb in recycled polyester.

A wide bandgap is one of the major obstacles that hamper the photoelectric application of ferroelectrics. This work reported the tunable band gaps of ferroelectric Aurivillius Bi3.15Nd0.85Ti3O12 (BNdT) by B-site X (X = Ni, Co, Cr Mn, or Fe) substitution. The analysis of the UV–vis absorption spectra showed a decrease in the band gap induced by substitution and the valence band XPS (VBXPS) spectra indicated that the substitution of X ions elevates the valence band maximum (VBM). The octahedral distortion was estimated qualitatively by Raman analysis and quantitatively through the structural refinements. It is found that the change of the energy band structure and the band gap tuning are proportional to the octahedral distortion induced by B-site substitution. To our knowledge it's the first time to relate the octahedral distortion to the band gap tuning quantitatively for ferroelectric Aurivillius compounds, and the present work will shed light on the mechanism of band gap tuning of ferroelectric oxides materials and provide an available way on manipulating oxide optoelectronics.

Abscission is triggered by multiple environmental and developmental cues, including endogenous plant hormones. KNOTTED-LIKE HOMEOBOX (KNOX) transcription factors (TFs) play an important role in controlling abscission in plants. However, the underlying molecular mechanism of KNOX TFs in abscission is largely unknown. Here, we identified LcKNAT1, a KNOTTED-LIKE FROM ARABIDOPSIS THALIANA1 (KNAT1)-like protein from litchi, which regulates abscission by modulating ethylene biosynthesis. LcKNAT1 is expressed in the fruit abscission zone and its expression decreases during fruitlet abscission. Furthermore, the expression of the ethylene biosynthetic genes LcACS1, LcACS7, and LcACO2 increases in the fruit abscission zone, in parallel with the emission of ethylene in fruitlets. In vitro and in vivo assays revealed that LcKNAT1 inhibits the expression of LcACS/ACO genes by directly binding to their promoters. Moreover, ectopic expression of LcKNAT1 represses flower abscission in tomatoes. Transgenic plants expressing LcKNAT1 also showed consistently decreased expression of ACS/ACO genes. Collectively, these results indicate that LcKNAT1 represses abscission via the negative regulation of ethylene biosynthesis.

Summary Edge/bottomwater cresting or even breaking into the wellbore has been a major factor affecting crude-oil production and has not been overcome so far. Aiming at this problem, this paper designs a new autonomous inflow-control device (AICD) profile control tool—swirling AICD—on the basis of the research of profile control tools used in the past. The AICD is mainly based on the principle of automatic phase separation, the splitting of three-way pipes, and the principle of vortex depressurization. Combined with the special flow path, the production of edge/bottomwater can be effectively restrained. Computational fluid dynamics (CFD) numerical simulation and indoor flow experiments are used to prove the water-control function of the swirling AICD, to obtain the pressure and velocity distribution of fluid flow in the AICD, and to obtain the influencing factors and their influence rules. Based on these analyses, we established the swirling AICD mathematical model, which has laid a theoretical foundation for the application of swirling AICDs in wells.

The structure and biocompatibility of anode materials significantly affect the performance of microbial fuel cells (MFCs). A biocompatible polyaniline–sodium alginate (PANI–SA) composite was prepared in situ oxidation polymerization on the 3D porous nitrogen-doped carbon nanotube/sponge (NCNT/S) to construct a high-performance microbial fuel cell in this investigation. The SEM showed that PANI–SA composite anode had a three-dimensional macroporous structure, and nitrogen-doped nanotubes were wound around the sponge skeleton, which had a large specific surface area, provided more places for the attachment and growth of microorganisms. A dual-chamber MFC equipped with a PANI–SA/NCNT/S bioanode to achieve a power density of 4380 mW m−3, which was much greater than the other MFCs. During the charge–discharge time of 60–90 min, the PANI–SA/NCNT/S bioanode had the highest total charge value of 26,617.86 C m−2, which was 3.23 times higher than that of NCNT/S (8231.87 C m−2). High-throughput sequencing results showed that the PANI–SA/NCNT/S bioanode exhibited high community diversity and selective enrichment of electrogenic bacteria. The excellent performance of the MFC equipped with PANI–SA/NCNT/S anode was attributed to the composite materials, which could be attributed to the large-pore network structure, better biocompatibility, large capacitance and high specific surface area. Illustration of the process for the preparation of PANI–SA

In this paper, we present an automatic inspection system based on micro motion sensors for detecting the “looseness” of rail fasteners. The system is composed of a low-power MEMS accelerometer and a Global System for Mobile Communications (GSM) unit, and can detect loose fasteners and upload the results to a cloud server in real-time. Finite Element Method (FEM) is used to analyze rail vibration characteristics in the vertical direction as the rail is excited by mechanical pulse inputs. On this basis, the Chao-Shen Entropy theory was applied to identify fastener looseness reliably. In addition, field experiments were also conducted on Datong-Qinhuangdao Railway, the longest coal-transport railway in the world. The experimental results show that fastener looseness can slow down the attenuation of rail vibration in the time domain and produce a large entropy value. Using the method of amplitude entropy, loose fasteners can be identified reliably for looseness factor >60%. The proposed system has been experimental validated to enable real-time detection of railway fastener looseness and could potentially bring significant benefits for the day-to-day maintenance of railways.

Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three-layered Cu2 S@carbon@MoS2 as anode materials for sodium-ion batteries is reported. Through a facile multistep template-engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen-doped carbon-coated Cu2 S nanoboxes to realize the Cu2 S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three-layered Cu2 S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version

Horticultural commodities suffer chilling injury following exposure to extremely low temperatures, which results in visible symptoms and considerable quality loss. Therefore, it is of significance to understand the mechanism of this physiological disorder and to develop effective strategies to control it. Chilling stress causes alteration in structure and function of the plasma membrane, which is assumed to be the primary event in response to cold stress. During this process, the membrane lipid metabolism plays a pivotal role in membrane fluidity and stability. In this review, we summarized the possible roles of membrane lipid metabolism in the development of chilling injury, having the potential for developing effective strategies to alleviate chilling injury in horticultural products under refrigerated storage in practice.

ZIF-67 comprises alternately arranged cobalt atoms and nitrogen-rich organic linkers, making it an ideal single source precursor to producing Co and N co-doped carbon (C-ZIF-67) catalyst for oxygen reduction reaction (ORR). C-ZIF-67 particle catalyst in air-cathode, however, often shows limited activity and stability because of the particle-to-particle resistances and particle detachment issues. Herein, we introduce an in-situ approach to selectively growing ZIF-67 on electrospun polyacrylonitrile (PAN) fibers, forming an interesting “gems-on-string” structured PAN@ZIF-67 hybrid. Upon pyrolysis the hybrid is converted to conductive C-PAN@ZIF-67 with well-retained hierarchical structure, showing high ORR activity with excellent durability in alkaline electrolyte. A zinc-air battery (ZnAB) using C-PAN@ZIF-67 in air-cathode delivers a stable discharge voltage of 1.24 V at a high current density of 20 mA cm−2. With the regeneration of the cell after its full-discharges by mechanically replenishing the zinc anode and the electrolyte, a continuous operation over 38 days is demonstrated with the discharge voltage above 1.0 V at a current density of 10 mA cm−2. Significantly, a freestanding C-PAN@ZIF-67 mat serves directly as the flexible cathode for thin and bendable ZnABs to deliver high discharge voltages in both flat and bent states, promising great potential for future wearable electronics.

The study of microscopic structure of a liquid/liquid interface is of fundamental importance due to its close relation to the thermodynamics and kinetics of interfacial charge transfer reactions. In this article, the microscopic structure of a non-polarizable water/nitrobenzene (W/NB) interface was evaluated by scanning ion conductance microscope (SICM). Using SICM with a nanometer-sized quartz pipette filled with an electrolyte solution as the probe, the thickness of this type of W/NB interface could be measured at sub-nanometer scale, based on the continuous change of ionic current from one phase to another one. The effects for thicknesses of the non-polarizable W/NB interfaces with different electrolyte concentrations, the Galvani potentials at the interface and the applied potentials on the probe were measured and systematically analyzed. Both experimental setups, that is an organic phase up and an aqueous down, and a reverse version, were employed to acquire the approach curves. These data were compared with those of an ideal polarizable interface under the similar experimental conditions, and several characteristics of non-polarizable interfaces were found. The thickness of a non-polarizable interface increases with the decrease of electrolyte concentration and the increase of applied potential, which is similar to the situation of a polarizable liquid/liquid interface. We also find that the Galvani potential across a non-polarizable interface can also influence the interfacial thickness, this phenomenon is difficult to observe when using polarizable interface. Most importantly, by the comparison of two kinds of liquid/liquid interfaces, we experimentally proved that much more excess ions are gathered in the space charge layer of non-polarizable interfaces than in that of polarizable interfaces. These results are consistent with the predictions of molecular dynamic simulations and X-ray reflectivity measurements.

The construction of hybrid architectures for electrode materials has been demonstrated as an efficient strategy to boost sodium-storage properties because of the synergetic effect of each component. However, the fabrication of hybrid nanostructures with a rational structure and desired composition for effective sodium storage is still challenging. In this study, an integrated nanostructure composed of copper-substituted CoS2 @Cux S double-shelled nanoboxes (denoted as Cu-CoS2 @Cux S DSNBs) was synthesized through a rational metal-organic framework (MOF)-based templating strategy. The unique shell configuration and complex composition endow the Cu-CoS2 @Cux S DSNBs with enhanced electrochemical performance in terms of superior rate capability and stable cyclability. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version

Accurate predictions of decaying swirling flow behavior in the multi-lobed swirl generator (MLSG) are essential for certain engineering applications. In this study, decaying swirling flow characteristics in an MLSG are examined using the Computational Fluid Dynamics (CFD) technique with a Reynolds stress turbulence model (RSM). The effects of different lobe numbers (n) and pitch length ratios (P/D) on swirl intensity, pressure drop, friction factor coefficient, and decay rate are observed with Reynolds number from 50,000 to 125,000. Combined with the pressure loss, the efficiency of swirl induction is evaluated by introducing a swirl effectiveness (SE) evaluation criterion. The initial swirl intensity is shown to first increases and then decreases as lobe number increases. The maximum value is obtained at lobe number n = 4. The pitch length ratios P/D corresponding to the optimal SE value obtained from different lobe also differ. The optimal SE value is achieved at n = 4 and P/D = 8. The friction factor ratio fs/fp decreases as pitch length ratio increases, but the decreasing trend decelerates over time. Correlations based on the numerical predictions of friction factor ratio fs/fp and decay rate β are presented accordingly.

Medical micro/nanorobots have received tremendous attention over the past decades owing to their potential to be navigated into hard-to-reach tissues for a number of biomedical applications ranging from targeted drug/gene delivery, bio-isolation, detoxification, to nanosurgery. Despite the great promise, the majority of the past demonstrations are primarily under benchtop or in vitro conditions. Many developed micro/nanoscale propulsion mechanisms are based on the assumption of a homogeneous, Newtonian environment, while realistic biological environments are substantially more complex. Moving toward practical medical use, the field of micro/nanorobotics must overcome several major challenges including propulsion through complex media (such as blood, mucus, and vitreous) as well as deep tissue imaging and control in vivo. In this review article, we summarize the recent research efforts on investigating how various complexities in biological environments impact the propulsion of micro/nanoswimmers. We also highlight the emerging technological approaches to enhance the locomotion of micro/nanorobots in complex environments. The recent demonstrations of in vivo imaging, control and therapeutic medical applications of such micro/nanorobots are introduced. We envision that continuing materials and technological innovations through interdisciplinary collaborative efforts can bring us steps closer to the fantasy of "swallowing a surgeon".

Interfacial electron transfer between electroactive biofilm and the electrode was crucial step for microbial fuel cells (MFCs). A three-dimensional multilayer porous sponge coating with nitrogen-doped carbon nanotube/polyaniline/manganese dioxide (S/N-CNT/PANI/mnO2) electrode has been developed for MFC anode. Here, the S/N-CNT/PANI/MnO2 anode can function as a biocapacitor, able to store electrons generated from the degradation of organic substrate under the open circuit state and release the accumulated electrons upon requirement. Thus, the mismatching of the production and demand of the electricity can be overcome. Comparing with the sponge/nitrogen-doped carbon nanotube (S/N-CNT) bioanode, S/N-CNT/PANI/MnO2 capacitive bioanode displays a strong interaction with the microbial biofilm, advancing the electron transfer from exoelectrogens to the bioanode. The maximum power density of MFC with S/N-CNT/PANI/MnO2 capacitive bioanode is 1019.5 mW/m2, which is 2.2 and 5.8 times as much as that of S/N-CNT/MnO2 bioanode and S/N-CNT bioanode (470.7 mW/m2 and 176.6 mW/m2), respectively. During the chronoamperometric experiment with 60 min of charging and 20 min of discharging, the S/N-CNT/PANI/MnO2 capacitive bioanode was able to store 10743.9 C/m2, whereas the S/N-CNT anode was only able to store 3323.4 C/m2. With a capacitive bioanode, it is possible to use the MFC simultaneously for production and storage of electricity

Carotenoids are a class of bioactive compounds that exhibit health-promoting properties for humans, but their regulation in bananas during fruit ripening remains largely unclear. Here, we found that the total carotenoid content continued to be elevated along the course of banana ripening and peaked at the ripening stage followed by a decrease, which is presumably caused by the transcript abundances of carotenoid biosynthetic genes MaLCYB1.1 and MaLCYB1.2. Moreover, a ripening-inducible transcription factor MaSPL16 was characterized, which was a nuclear protein with transactivation activity. Transient transformation of MaSPL16 in banana fruits led to enhanced transcript levels of MaLCYB1.1 and MaLCYB1.2 and hence the total carotenoid accumulation. Importantly, MaSPL16 stimulated the transcription of MaLCYB1.1 and MaLCYB1.2 through directly binding to their promoters. Collectively, our findings indicate that MaSPL16 behaves as an activator to modulate banana carotenoid biosynthesis, which may provide a new target for molecular improvement of the nutritional and bioactive qualities of agricultural crops that accumulate carotenoids.

By comparing optical spectral results of both Sn-rich and Sn-poor Cu2ZnSnS4 (CZTS) with the previously calculated defect levels, we confirm that the band-tail states in CZTS originate from the high concentration of 2CuZn + SnZn defect clusters, whereas the deep-donor states originate from the high concentration of SnZn. In Sn-rich CZTS, the absorption, reflectance, and photocurrent (PC) spectra show band-tail states that shrink the bandgap to only ∼1.34 eV, while photoluminescence (PL) and PC spectra consistently show that abundant CuZn + SnZn donor states produce a PL peak at ∼1.17 eV and abundant SnZn deep-donor states produce a PL peak near 0.85 eV. In contrast, Sn-poor CZTS shows neither bandgap shrinking nor any deep-donor-defect induced PL and PC signals. These results highlight that a Sn-poor composition is critical for the reduction of band-tailing effects and deep-donor defects and thus the overcoming of the severe open-circuit voltage (Voc) deficiency problem in CZTS solar cells.