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The efficacy and safety of mRNA vaccines both rely on a fine-tuning of specific humoral and cellular immune responses. Instead of adjustments in vaccine component, we proposed a concept of chronological management of adjuvant effect to modulate the adaptive immune potency and preference inspired by natural virus infection. By simulating type I interferon expression dynamics during viral infection, three vaccine strategies employing distinct exposure sequences of adjuvant and mRNA have been developed, namely Precede , Coincide , and Follow . Follow , the strategy of adjuvant administration following mRNA, effectively suppressed tumor progression, which was attributed to enhanced mRNA translation, augmented p-MHC I expression, and elevated CD8 + T cell response. Meanwhile, Follow exhibited improved biosafety, characterized by reduced incidences of cardiac and liver toxicity, owing to its alteration to the vaccination microenvironment between successive injections. Our strategy highlights the importance of fine-tuning adjuvant effect dynamics in optimizing mRNA vaccines for clinical application.

The accurate discernment and separation of chiral isomers with high precision remain a significant challenge in various industries and biological fields. In this investigation, an electrochemiluminescent (ECL) chiral recognition platform was devised to ascertain the presence of phenylalanine (Phe). Notably, a homochiral [Ni 2 (l-asp) 2 (bipy)] (Ni-LAB) was established as a dual-function coreactant accelerator and chiral recognition substrate. Ni-LAB facilitates the reaction between the coreactant (K 2 S 2 O 8 ) and the luminescent entity 3,4,9,10-perylenetetracar-boxylic-l-cysteine (PTCA-cys), thereby enhancing the ECL luminescence efficiency and improving the sensitivity of the chiral sensor. The chiral recognition potential of Ni-LAB was assessed to differentiate between Phe chiral isomers, and the underlying mechanism was comprehensively elucidated. This system exhibited remarkable proficiency in detecting Phe enantiomers and precisely differentiating a single Phe enantiomer within a mixture, showcasing exceptional levels of selectivity, stability, and reproducibility. This study paves the way for the development of advanced chiral recognition systems, potentially revolutionizing the field of chiral sensing and discrimination.

Several tobamoviruses cause substantial economic losses to tomato and pepper crops globally, especially the pepper mild mosaic virus (PMMoV), tomato brown rugose fruit virus (ToBRFV), tomato mosaic virus (ToMV), and tomato mottle mosaic virus (ToMMV). A fast and accurate detection method is essential for virus identification. An all-in-one reaction method combining a one-step reverse-transcription recombinase-aided amplification (RT-RAA) and CRISPR/Cas12a-based lateral flow assay in one mixture was developed to rapidly screen and accurately differentiate among these four tobamoviruses for field detection in tomato and pepper plants. With a generic RT-RAA primer set and a mix of four specific crRNAs, along with a portable metal incubator and the use of a crude extraction method, this method screened for PMMoV, ToBRFV, ToMV, and ToMMV concurrently in less than 1 h, enabling field workers to take action immediately. The accurate differentiation of these four viruses could be achieved by later adding a single specific crRNA.

The recognition and separation of chiral isomers are of great importance in both industrial and biological applications. In this study, a chiral recognition system based on electrochemiluminescence was established for the detection of penicillamine (PA) enantiomers. The system utilized a homochiral [Zn 2 (BDC)(d-lac)] (Zn-BL) platform for the uniform distribution of Ru(bpy) 3 2+ nanoparticles, effectively mitigating aggregation-caused quenching. The chiral recognition ability of Zn-BL was tested to distinguish between PA enantiomers, and the results indicated a substantial increase in the chiral electrochemiluminescence (ECL) signal when l-PA was present, in contrast to d-PA. The mechanism underlying ECL chiral discrimination was investigated using water contact angle measurements, DFT calculations, and electrochemical characterization. The system exhibited high selectivity, stability, and reproducibility for PA enantiomer detection. Furthermore, the proposed method can accurately identify one enantiomer of PA in a mixture. This study provides a reliable and sensitive approach for achieving the highly selective detection of chiral molecules.

Fe-modified biochars have been widely used in removal of Cr(VI) from water due to the resulting modified surface functional groups and magnetization property. However, few studies have synthetically investigated modification methods and synthesis parameters on the improvement of the removal efficiency of Cr(VI) by Fe-modified biochars. Herein, 10 types of corn straw-based magnetic biochars were produced using pre-modification and post-modification methods with various modifier ratios, and the highest heating temperature (HHT). Cr(VI) removal results suggest that the removal efficiency of pre-modified biochars ranged from 50.7 to 98.6%, which was much higher than that of post-modified (6.6-21.6%) and unmodified biochars (0.4-7.6%). The effect of synthesis methods on Cr(VI) adsorption was in the following order: Fe-modification method > modifier ratio > HHT. The adsorption kinetics and isotherm results of three types of pre-modified biochars were well fitted with the pseudo-second-order model ( R 2 > 0.99) and the Langmuir adsorption model ( R 2 > 0.99), respectively, indicating the surface homogeneity of the pre-modified biochars and unilayer chemisorptions of Cr(VI). Characterization results show that iron oxides or zerovalent iron particles were successfully deposited onto the surface of biochars and magnetism was introduced. A good Pearson correlation ( r = -0.9694) between the removal efficiency and pH value in modified biochar suggests that the lower pH value may offer more positive charges and promote electrostatic attraction. Therefore, the dominant mechanism for enhanced Cr(VI) adsorption on pre-modified biochar was electrostatic attraction, resulting from its distinguished acidity nature. Our findings provide new insights into the high-efficiency removal of Cr(VI) onto Fe-modified magnetic biochars and will benefit future design of more efficient magnetic biochars., Competing Interests: The authors declare no competing financial interest., (© 2020 American Chemical Society.)

Thermal energy storage (TES) systems are a key technology that utilizes renewable energy and low-level thermal energy to ensure continuous and stable operation in concentrated solar power plants, family heating, and industrial waste heat recovery fields. It solves the intermittent problem of solar radiation and significantly improves energy efficiency and economic benefits. Three varieties of natural basalt ores have been selected, namely, intermediate, basic, and ultrabasic basalt, which have been prepared into basalt glasses by the melt-quenching method. The applicability of basalt glass to high-temperature heat storage applications is studied. In the present paper, the chemical composition and structure of basalt glasses have been determined. The effect of temperature and composition on key thermophysical properties such as density, heat capacity, thermal diffusion, thermal conductivity, and thermal expansion has been analyzed during a series of thermal cycles. It has been confirmed that basalt glass has extremely high heat storage performance and thermal stability, and its working temperature is as high as 1000 °C such that it can be used as a solar energy heat storage material., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

For the first time, we report the formation of a chiral MOF-based helical nanomaterial ( h -HDGA@ZIF-67) through arranging zeolitic imidazolate framework (ZIF-67) nanocrystals on helical l-glutamic acid terminated bolaamphiphile ( h -HDGA) via a facile process at room temperature. The self-assembly leads to the chiral function of the ZIF-67 from an achiral ligand. The h -HDGA@ZIF-67 served as a new type of electrochemical sensing interface for recognizing and quantifying Pen enantiomers that realize significant enantioselectivity, satisfactory stability, and reproducibility. The synergetic effect from ZIF-67 nanocrystals on h -HDGA and stereoselectivity of h -HDGA@ZIF-67 lead to the excellent enantioselectivity. The present strategy showed the first example of a chiral MOF-based supramolecule helical nanomaterial, presenting high enantioselectivity for electrochemical enantiomeric determination.

We synthesize hollow polyhedral arrays composed of honeycomb-like nanosheets of Co 3 O 4 nanocrystals imbedded on carbon quantum dots (CQDs)- and nitrogen-codoped carbon matrix via a facile in situ air oxidation pyrolysis for CQDs-incorporated metal-organic framework polyhedral arrays. The function of CQDs hollowing and forming porous nanosheet shells was found. The resulting hierarchical architecture displays excellent oxygen evolution reaction activity with a low overpotential of 301 mV to drive 100 mA cm -2 in 1.0 M KOH and long-playing durability in oxygen evolution. The high performance can be ascribed to its highly dispersed Co 3 O 4 nanocrystals, CQDs and nitrogen codoping, internal cavities, and hierarchical pore system.

We combine the telomerase extension reaction and microRNA (miRNA)-induced rolling circle amplification, followed by graphene oxide (GO) and nicking enzyme-assisted signal amplification as a method to analyze telomerase and miRNA-21 in urine samples with the following merits. First, it is a binary assay and can simultaneously output double signals that correspond to the quantities of telomerase and miRNA, respectively. Second, telomerase activity is enhanced by using a DNA molecular beacon probe to inhibit the formation of G-quadruplex. Third, background noise is decreased significantly via introduction of GO. Fourth, performance tests on about 258 urine samples demonstrate that this binary assay can distinguish between urine from bladder cancer patients, those with cystitis, and normal individuals. Finally, this strategy also shows great potential in distinguishing between muscle-invasive bladder cancers and non-muscle-invasive bladder cancers. The proposed strategy will greatly contribute to clinical decision-making and individualized treatments.

We describe in this paper the structure-based design of a general class of heterocyclic mechanism-based inhibitors of the serine proteinases that embody in their structure a novel peptidomimetic scaffold (1,2,5-thiadiazolidin-3-one 1,1-dioxide). Sulfone derivatives of this class (I) were found to be time-dependent, potent, and highly efficient irreversible inhibitors of human leukocyte elastase, cathepsin G, and proteinase 3. The partition ratios for a select number of inhibitors were found to range between 0 and 1. We furthermore demonstrate that these inhibitors exhibit remarkable enzyme selectivity that is dictated by the nature of the P1 residue and is consistent with the known substrate specificity reported for these enzymes. Thus, inhibitors with small hydrophobic side chains were found to be effective inhibitors of elastase, those with aromatic side chains of cathepsin G, and those with a basic side chain of bovine trypsin. Taken together, the findings cited herein reveal the emergence of a general class of stable mechanism-based inhibitors of the serine proteinases which can be readily synthesized using amino acid precursors. Biochemical and high-field NMR studies show that the interaction of this class of inhibitors with a serine proteinase results in the formation of a stable acyl complex(es) and the release of benzenesulfinate, formaldehyde, and a low molecular weight heterocycle. The data are consistent with initial formation of a Michaelis-Menten complex, acylation of Ser195, and tandem loss of the leaving group. The initial HLE-inhibitor complex reacts with water generating formaldehyde and a stable HLE-inhibitor complex. Whether the initial HLE-inhibitor complex also reacts with His57 to form a third complex is not known at this point. The desirable salient parameters associated with this class of inhibitors, including the expeditious generation of structurally diverse libraries of inhibitors based on I, suggest that this class of mechanism-based inhibitors is of general applicability and can be used in the development of inhibitors of human and viral serine proteinases of clinical relevance.