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This study found that, after microwave treatment at 560 W for 30 s, alkaline protease enzymolysis significantly reduced the allergenicity of ovalbumin (OVA). Furthermore, specific adsorption of allergenic anti-enzyme hydrolyzed peptides in the enzymatic products by immunoglobulin G (IgG) bound to magnetic bead further decreased the allergenicity of OVA. The results indicated that microwave treatment disrupts the structure of OVA, increasing the accessibility of OVA to the alkaline protease. A comparison between 17 IgG-binding epitopes identified through high-performance liquid chromatography–higher energy collisional dissociation–tandem mass spectrometry and previously reported immunoglobulin E (IgE)-binding epitopes revealed a complete overlap in binding epitopes at amino acids (AA)125–135, AA151–158, AA357–366, and AA373–381. Additionally, partial overlap was observed at positions AA41–59, AA243–252, and AA320–340. Consequently, these binding epitopes were likely pivotal in eliciting the allergic reaction to OVA, warranting specific attention in future studies. In conclusion, microwave-assisted enzymolysis synergized with magnetic bead adsorption provides an effective method to reduce the allergenicity of OVA.

In this work, a novel organodiphosphate-containing inorganic–organic hybrid polyoxoniobate (PONb) ring {(PO3CH2CH2PO3H)4Nb8O16}4–(Nb8P8) has been achieved by a one-pot hydrothermal method. The ring is constructed from a tetragonal {Nb8O36} motif and four {PO3CH2CH2PO3H} ligands. Interestingly, Nb8P8can be joined together via K–H2O clusters {K2(H2O)4(OH)2} to form one-dimensional chains {[K2(H2O)4(OH)2]Nb8P8}nand further linked by {Cu(en)2}2+(en = ethylenediamine) complexes, resulting in a three-dimensional supramolecular framework {[Cu(en)2]2[K2(H2O)4(OH)2]Nb8P8}·3en·H2O (1). 1exhibits good chemical and thermal stability and has a high water vapor adsorption capacity of ≤224 cm3g–1(22.71 mol·mol–1) at 298 K, outperforming most of the known polyoxometalate-based materials. Impedance measurements prove that 1can transfer protons with moderate conductivity. This study not only contributes to the structural diversity of organodiphosphate-containing PONbs and PONb rings but also provides a reference for the development of PONb-based materials with unique performance.

In the new tunnel under close distance through the existing tunnel risk source, the grouting scheme developed to compensate for stratum losses is still based on empirical methods, relying on the overburden thickness of existing tunnels. This can potentially lead to an excessively high or low probability of uplift of existing tunnels. Proposing a coupled deformation analysis method between the grouting construction and adjacent existing tunnels is of great theoretical significance for developing grouting schemes. In order to reasonably limit the design parameters of grouting construction, based on the theory of fluid–solid coupling elastic pore-column expansion and the theory of random media, the calculation method of stratum displacement which simultaneously considers the coexistence of grout compaction expansion and permeability diffusion mode is derived, and the accuracy of the calculation method is verified by engineering examples. The accuracy of this calculation method was verified through engineering examples. Combined with the deformation coordination condition, the existing tunnel is regarded as an elastic Euler-Bernoulli continuous beam, and the finite element coupling balance equation of the interaction between the existing tunnel and the surrounding soil is obtained. Based on this, a coupling calculation model of the grouting construction and the deformation response of the adjacent existing tunnel is established. Combined with three times of grouting construction examples in the shield tunneling project of Beijing Metro Line 12 under the existing airport line, the reliability of the coupling calculation model to determine the grouting construction parameters is verified. The calculation parameters in the coupling calculation model have clear physical meanings, which can provide a theoretical basis for the grouting design of similar risk source projects.

The outbreak of corona virus disease 2019 (Covid-19) imposes a major challenge in managing patients undergoing surgical operation. In this study, we analyzed clinical and transmission features of 25 cases of Covid-19 from a single thoracic department, including 13 patients and 12 health care staff. There were 13 males and 12 females. The median age of the patients was 61 (range: 51 to 69) years. The median age of the health care staff was 35 (range: 22 to 51) years. By the end of follow-up date (Mar. 3, 2020), there were 16 non-severe cases (64%) and 9 severe cases (36%), 5 cases were dead (20%). Nineteen (76%) of the infected cases were confirmed by SARS-CoV-2 nucleic acid test, the rest were clinically diagnosed as suspected Covid-19 cases, and 19 (76%) of the infected cases had positive exposure history. We found that COPD was significantly associated with severity and death (P=0.040, and P=0.038, respectively), and chest operation was significantly associated with death for Covid-19 patients (P=0.039). A potential “super spreader” may be the source of the transmission before the implementation of quarantine and comprehensive protection. It was concluded that Covid-19 is associated with poor prognosis for patients undergoing thoracic operation, especially for those with COPD. Implementation of comprehensive protective measures is important to control nosocomial infection.

A unique heteropolyoxotantalate (hetero-POTa) cluster [P2O7Ta5O14]7–(P2Ta5) was first developed using pyrophosphate as a key to open the ultrastable skeleton of the classical Lindqvist-type [Ta6O19]8–precursor. The P2Ta5cluster can serve as a general and flexible secondary building unit to create a family of brand-new multidimensional POTa architectures. This work not only promotes the limited structural diversity of hetero-POTa but also provides a practical strategy for new extended POTa architectures.

To improve the surface micropores and high-temperature oxidation resistance of micro-arc oxidation (MAO) coatings on TC4 titanium alloy, cerium dioxide (CeO2) particles were introduced into the electrolyte to prepare MAO composite coatings with different cerium dioxide contents. An X-ray diffractometer, a scanning electron microscope and a multifunctional material surface performance tester were used to analyze the phase composition, surface morphology and bonding force of the samples, respectively. The TC4 substrate, undoped MAO sample and optimally doped MAO sample were oxidized at 650, 750 and 850°C, respectively. The results show that the best-doped MAO samples show excellent high-temperature oxidation resistance at the three temperatures. Compared with the maximum oxidation weight gain per unit area of the undoped MAO sample, that of the optimally doped MAO sample decreased by 10.8, 19.6 and 22.1%, respectively. This is mainly because the thickness, hardness and adhesion of MAO coatings are all increased by doping cerium dioxide particles, and a dense protective layer can also be formed on the surface of the TC4 substrate. The invasion of the oxygen medium is effectively prevented. In this research work, the optimal addition amount of cerium dioxide is 6 g/l.

The expressions of both the Fisch–Boozer and Ohkawa currents are constructed, and a feasible and efficient calculation method is given. Simulation results of the Fokker–Plank code verify the expressions and the calculation method. We calculate and separate the Ohkawa and Fisch–Boozer currents on a single magnetic flux surface of the off-axis position. The Ohkawa current drive mechanism can be made dominant over the Fisch–Boozer mechanism to achieve a high driven current. This can be done by adjusting the parameters of electron cyclotron waves to make the power deposited in the off-axis region of the low-field side.

The concept of phase separation has been used to describe and interpret physicochemical phenomena in biological systems for decades. Many intracellular macromolecules undergo phase separation, where it plays important roles in gene regulation, cellular signaling, metabolic reactions and so on, due to its unique dynamic properties and biological effects. As the noticeable importance of phase separation, pioneer researchers have explored the possibility to introduce the synthetically engineered phase separation for applicable cell function. In this article, we illustrated the application value of phase separation in synthetic biology. We described main states of phase separation in detail, summarized some ways to implement synthetic condensates and several methods to regulate phase separation, and provided a substantial amount of identical examples to illuminate the applications and perspectives of phase separation in synthetic biology. Multivalent interactions implement phase separation in synthetic biology. Small molecules, light control and spontaneous interactions induce and regulate phase separation. The sy nthetic condensates are widely used in signal amplifications, designer orthogonally non‐membrane‐bound organelles, metabolic pathways, gene regulations, signaling transductions and controllable platforms. Studies on quantitative analysis, more standardized modules and precise spatiotemporal control of synthetic phase separation may promote the further development of this field. Author summary:A substantial amount of physical theories and biological experiments have been developed to uncover the underlying principles of phase separation in biology. The synthetic condensates through phase separation have been used to implement many specific functions in biological systems. In the future, more biomedical functions related to phase separation can be explored, more diseases triggered or accelerated by phase separation may be treated better, more artificial applications can be realized by synthetic condensates.

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease that was first reported in Wuhan, People’s Republic of China, and has subsequently spread worldwide. Clinical information on patients who contracted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the perioperative period is limited. Here, we report seven cases with confirmed SARS-CoV-2 infection in the perioperative period of lung resection. Retrospective analysis suggested that one patient had been infected with the SARS-CoV-2 infection before the surgery and the other six patients contracted the infection after the lung resection. Fever, lymphopenia, and ground-glass opacities revealed on computed tomography are the most common clinical manifestations of the patients who contracted COVID-19 after the lung resection. Pathologic studies of the specimens of these seven patients were performed. Pathologic examination of patient 1, who was infected with the SARS-CoV-2 infection before the surgery, revealed that apart from the tumor, there was a wide range of interstitial inflammation with plasma cell and macrophage infiltration. High density of macrophages and foam cells in the alveolar cavities, but no obvious proliferation of pneumocyte, was found. Three of seven patients died from COVID-19 pneumonia, suggesting lung resection surgery might be a risk factor for death in patients with COVID-19 in the perioperative period.

Quantitative information about protein–ligand interactions is central to drug discovery. To obtain the quintessential reaction dissociation constant, ideally measurements of reactions should be performed without perturbations by molecular labeling or immobilization. The technique of transient induced molecular electrical signal (TIMES) has provided a promising technique to meet such requirements, and its performance in a microfluidic environment further offers the potential for high throughput and reduced consumption of reagents. In this work, we further the development by using integrated TIMES signal (i-TIMES) to greatly enhance the accuracy and reproducibility of the measurement. While the transient response may be of interest, the integrated signal directly measures the total amount of surface charge density resulted from molecules near the surface of electrode. The signals enable quantitative characterization of protein–ligand interactions. We have demonstrated the feasibility of i-TIMES technique using different biomolecules including lysozyme, N,N′,N″-triacetylchitotriose (TriNAG), aptamer, p-aminobenzamidine (pABA), bovine pancreatic ribonuclease A (RNaseA), and uridine-3′-phosphate (3′UMP). The results show i-TIMES is a simple and accurate technique that can bring tremendous value to drug discovery and research of intermolecular interactions.

The self-renewal and differentiation properties of cancer stem cells (CSCs) result in chemoresistance in breast cancer. Even though numerous drugs have been developed to target CSCs, they have suffered from inefficient delivery and accumulation at the focal site. Here, a thermoresponsive hydrogel is developed by coencapsulating aggregation-induced emission (AIE)–active photothermal agent and thioridazine (THZ), demonstrating a controllable delivery system triggered by the AIE agent to augment THZ-mediated CSC ablation. Upon near-infrared laser stimuli, the photothermal effect from the AIE agent induces hydrogel deformation for burst drug release. The precise in situtumor administration of the hydrogel accelerates drug diffusion and accumulation in deep breast cancer lesions. Thus, THZ can invade tumors and provoke massive CSC apoptosis via dopamine receptor blockage and oxidative stress induction. Consequently, effective CSC inhibition and significant suppression of tumor recurrence and metastasis are demonstrated in mice with breast cancer. We believe that this intelligent hydrogel-based delivery system represents a promising treatment strategy for metastatic breast cancer with clinical potential.

Protein–ligand interaction detection without disturbances (e.g., surface immobilization, fluorescent labeling, and crystallization) presents a key question in protein chemistry and drug discovery. The emergent technology of transient induced molecular electronic spectroscopy (TIMES), which incorporates a unique design of microfluidic platform and integrated sensing electrodes, is designed to operate in a label-free and immobilization-free manner to provide crucial information for protein–ligand interactions in relevant physiological conditions. Through experiments and theoretical simulations, we demonstrate that the TIMES technique actually detects protein–ligand binding through signals generated by surface electric polarization. The accuracy and sensitivity of experiments were demonstrated by precise measurements of dissociation constant of lysozyme and N-acetyl-d-glucosamine (NAG) ligand and its trimer, NAG3. Computational fluid dynamics (CFD) computation is performed to demonstrate that the surface’s electric polarization signal originates from the induced image charges during the transition state of surface mass transport, which is governed by the overall effects of protein concentration, hydraulic forces, and surface fouling due to protein adsorption. Hybrid atomistic molecular dynamics (MD) simulations and free energy computation show that ligand binding affects lysozyme structure and stability, producing different adsorption orientation and surface polarization to give the characteristic TIMES signals. Although the current work is focused on protein–ligand interactions, the TIMES method is a general technique that can be applied to study signals from reactions between many kinds of molecules.

AbstractWaste water containing metal ions is one of the main pollution sources of surface water and groundwater, and must be removed effectively. In this paper, nitrogen-containing porous carbons, the 800KH-H2O and the 800KH-NH3, were synthesized using sunflower plates as the major carbon source carbonized at 800°C and activated with distilled water and concentrated aqueous ammonia at the same temperature. The porous carbons were characterized by surface area analyzer, Fourier transform infrared, element analysis, and scanning electron microscopy. The adsorption properties of the porous carbons toward metal ions were studied by batch methods. The test results show that the average pore diameter of porous carbon is smaller than 2 nm, and nitrogen-containing chemical groups were formed on its surface. The adsorption capacities of the 800KH-NH3toward Pb2+are as high as 786 mg g−1due to its developed pore structure and nitrogen-containing chemical groups. The adsorption process could be well described by the intraparticle mass transfer diffusion model and the Langmuir–Freundlich model.

Waste water containing metal ions is one of the main pollution sources of surface water and groundwater, and must be removed effectively. In this paper, nitrogen-containing porous carbons, the 800KH-H2O and the 800KH-NH3, were synthesized using sunflower plates as the major carbon source carbonized at 800°C and activated with distilled water and concentrated aqueous ammonia at the same temperature. The porous carbons were characterized by surface area analyzer, Fourier transform infrared, element analysis, and scanning electron microscopy. The adsorption properties of the porous carbons toward metal ions were studied by batch methods. The test results show that the average pore diameter of porous carbon is smaller than 2 nm, and nitrogen-containing chemical groups were formed on its surface. The adsorption capacities of the 800KH-NH3toward Pb2+are as high as 786 mg g−1due to its developed pore structure and nitrogen-containing chemical groups. The adsorption process could be well described by the intraparticle mass transfer diffusion model and the Langmuir–Freundlich model.

Nucleic acid detection and quantification technologies have made remarkable progress in recent years. Among existing platforms, hybridization-based assays have the advantages of being amplification free, low instrument cost, and high throughput, but are generally less sensitive compared to sequencing and PCR assays. To bridge this performance gap, we developed a quantitative physical model for the hybridization-based assay to guide the experimental design, which leads to a pico-liter droplet environment with drastically enhanced performance and detection limit several order above any current microarray platform. The pico-liter droplet hybridization platform is further coupled with the on-chip enrichment technique to yield ultrahigh sensitivity both in terms of target concentration and copy number. Our physical model, taking into account of molecular transport, electrostatic intermolecular interactions, reaction kinetics, suggests that reducing liquid height and optimizing target concentration will maximize the hybridization efficiency, and both conditions can be satisfied in a highly parallel, self-assembled pico-liter droplet microarray that produces a detection limit as low as 570 copies and 50 aM. The pico-liter droplet array device is realized with a micropatterned superhydrophobic black silicon surface that allows enrichment of nucleic acid samples by position-defined evaporation. With on-chip enrichment and oil encapsulated pico-liter droplet arrays, we have demonstrated a record high sensitivity, wide dynamic range (6 orders of magnitude), and marked reduction of hybridization time from >10 h to <5 min in a highly repeatable fashion, benefiting from the physics-driven design and nanofeatures of the device. The design principle and technology can contribute to biomedical sensing and point-of-care clinical applications such as pathogen detection and cancer diagnosis and prognosis.

Resin D301 was surface-carbonized to obtain the surface charring materials (CD301). Using redox initiating system constituted by the amino groups of CD301 particles and persulfate in the solution, the poly (sodium styrene sulfonate) (PSSS) was grafted onto the surface of CD301, obtaining the grafted material PSSS-g-CD301, and the degree of grafting can reach 17.7% under suitable conditions. PSSS-g-CD301 was characterized by infrared spectrum (FTIR), and the degree of grafting was measured by gravimetric method. The adsorption character of PSSS-g-CD301 towards Al3+, Fe3+ and Cu2+ were mainly examined and investigated. PSSS-g-CD301 possesses strong adsorption ability towards Al3+, Fe3+and Cu2+. The adsorption capacity can get up to 13.285mg·g-1, 14.864mg·g-1, and 15.10mg·g-1, respectively. The data of isothermal adsorption matched well with Langmuir equation. The adsorption capacity increased with the increase of temperature and the value of pH. The adsorption capacity of PSSS-g-CD301 towards Fe3+ changed little after use them six times.