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Developing a promising strategy to improve the limited selectivity and activity of traditional Pd–Cu bimetallic catalysts for CO2 hydrogenation to methanol (CH3OH) remains a grand challenge.

Background To investigate the safety, feasibility, and oncological outcomes of total laparoscopic right hemicolectomy with transvaginal specimen extraction in the treatment of right-sided colon cancer. Methods We retrospectively reviewed patients with right-sided colon cancer who received total laparoscopic right hemicolectomy in our hospital between January 2017 and January 2020. The patients who underwent abdominal incision were included in the control group and the patients who underwent vaginal incision group were included in the study group. The perioperative characteristics and outcomes were compared between these two groups. Results 25 patients were included in the study group and 55 patients were included in the control group. In terms of baseline data, including age, preoperative body mass index, American Society of Anesthesiologists classification, tumor transverse diameter, tumor location, pathologic differentiation, preoperative clinical staging, there were no significant differences between the two groups (P > 0.05). There were no significant differences in terms of operative duration, intraoperative blood loss, length of resected colon, number of detected lymph nodes, postoperative complications, and postoperative pathological stages between the two groups (P > 0.05). There were statistically significant differences in postoperative pain intensity, time to passage of flatus, and length of postoperative hospital stay between the two groups (P 0.05), after the surgery between the two groups. The one-year tumor-free survival rate was 100% in both groups. Conclusions Total laparoscopic right hemicolectomy with transvaginal specimen extraction is a safe and feasible method, with satisfactory oncological outcomes, to treat patients with right-sided colon cancer.

Calculation of REV (representative elementary volume) properties of geological porous media refers to the process of creating a 3D digital representation of a rock sample, typically obtained from imaging techniques such as X-ray microtomography. This technique allows for a detailed analysis of the internal structure and the properties of rocks, as well as precise calculation of various flow parameters. However, one major challenge with calculation of REV properties of geological porous media is the high computational cost required to generate accurate results, especially for large and complex samples. In this study, we constructed 3D digital cores of dune sand and fractured shale using CT scanning technology, and then used two image processing techniques, namely digital core image resampling and cutting, to reduce the computational cost of calculating digital core permeability. Next, a fast permeability calculation method is employed to reduce the complexity of permeability calculation. Finally, we summarized the applicability of different image processing methods to different rock samples, and provided prerequisites for high computational cost digital core permeability calculation.

Enzymatic hydrolysis of crystalline chitin is a solid–liquid interfacial catalysis process that is highly dependent on the enzymes’ processivity, namely, the number of catalytic cycles consecutivel...

Photoelectrochemical (PEC) biosensors have shown great promise in bioanalysis and diagnostic applications in recent years. In this work, the CuO/Cu2O nanowire array (CuO/Cu2O Nanowire) supported on copper foam was prepared as a photocathode for detection of tyrosinase though quinone-chitosan conjugation chemistry method. The in-situ generated quinones that were the catalytic product of tyrosinase acted as electron acceptors, which were captured by the chitosan deposited on the surface of the electrode. Direct immobilization of electron acceptor on the electrode surface improved the photocurrent conversion efficiency and thus sensitivity. The as-prepared biosensor can realize a rapid response in a wide linear range of 0.05 U/mL to 10 U/mL with the detection limit as low as 0.016 U/mL of tyrosinase. The current work provides a new perspective to design and develop highly sensitive and selective PEC biosensor.

In the manufacturing process, the production of standardized prefabricated components is highly efficient, which can benefit the demand for mass production of standardized architecture after World War II. However, over-standardized architecture sometimes cannot satisfy the demand for uniqueness in an architecture project. At this time, bespoke components began to be used to solve the over-simplification of aesthetics of architecture. Besides, with the help of digital fabrication, bespoke components could achieve mass customization in architecture. The research designs two joints: prefabricated aluminum joints and bespoke aluminum joints, which aims to develop bespoke joints to aluminum components with ornamental characteristics and become a part of architecture with practical function and ornamental function. Furthermore, in the process of generating bespoke joints, improve the deficiency when conducting lost-foam casting.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO subgroup I-like proteins, which contain an AA15 LPMO catalytic domain and a conserved C-terminal cysteine-rich motif, two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen for study. RNAi for the T. castaneum protein, TcLPMO1, caused molting arrest at all developmental stages, whereas RNAi of the L. migratoria protein, LmLPMO1, prevented only adult eclosion. In both species, LPMO1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO1-like protein from Ostrinia furnacalis (rOfLPMO1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal for the first time the physiological importance of catalytically active LPMO1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of chitin turnover during molting.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO15 subgroup I-like proteins (LPMO15-1s), two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen. Depletion by RNAi of T. castaneum TcLPMO15-1 caused molting arrest at all developmental stages, whereas depletion of the L. migratoria LmLPMO15-1, prevented only adult eclosion. In both species, LPMO15-1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of the chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO15-1-like protein from Ostrinia furnacalis (rOfLPMO15-1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal the physiological importance of catalytically active LPMO15-1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of cuticular chitin turnover during molting.

We report a novel and potential wound dressing hydrogel based on DNA and a green industrial microbiocide tetrakis (hydroxymethyl) phosphonium sulfate (THPS) via one-pot self-assembly. Intermolecular electrostatic interaction and hydrogen bonding between DNA and THPS together drive the formation of the adhesive DNT (DNA+THPS) hydrogel, featuring with self-healing, shear-thinning and injectability. This wound dressing hydrogel possesses broad-spectrum antibacterial ability with low cytotoxicity to L929 cells. Furthermore, the wound dressing can reduce the risk of wound infection by releasing THPS to suppress bacterial spread and accelerate wound healing. The low cost and simple preparation may make the hydrogel attractive in biomedical applications and could be a good reference to others.

Ammonia (NH3) is an activated nitrogen building block for the manufacture of modern fertilizers, plastics, fibers, explosives, etc.; however, its production is limited to the traditional Haber–Bosch process. Very recently, electrocatalytic reduction of nitrogen (N2) has been demonstrated to be a clean and sustainable approach to produce NH3, which has aroused widespread attention. All types of electrocatalysts have been developed and designed for the electrochemical nitrogen reduction reaction (NRR). To achieve both high catalytic performance and selectivity, electrocatalysts must be rationally designed to optimize the mass transport, chemi(physi)sorption, and transfer of protons and electrons. In this review, we summarize the recent developments on electrocatalysts for N2 fixation. First, we discuss the reaction mechanisms of the NRR. Second, three categories of electrocatalysts according to their chemical compositions are surveyed. Then, the effects of different types of electrolytes on NRR activity and electrolyte choice are also summarized. Finally, the existing challenges and future perspectives are discussed.

In multi-type resource allocation (MTRA) problems, there are $$d\ge 2$$ types of items, and n agents who each demand one unit of items of each type and have strict linear preferences over bundles consisting of one item of each type. For MTRAs with indivisible items, our first result is an impossibility theorem that is in direct contrast to the single type ( $$d=1$$ ) setting: no mechanism, the output of which is always decomposable into a probability distribution over discrete assignments (where no item is split between agents), can satisfy both sd-efficiency and sd-envy-freeness. We show that this impossibility result is circumvented under the natural assumption of lexicographic preferences. We provide lexicographic probabilistic serial (LexiPS) as an extension of the probabilistic serial (PS) mechanism for MTRAs with lexicographic preferences, and prove that LexiPS satisfies sd-efficiency and sd-envy-freeness, retaining the desirable properties of PS. Moreover, LexiPS satisfies sd-weak-strategyproofness when agents are not allowed to misreport their importance orders. For MTRAs with divisible items, we show that the existing multi-type probabilistic serial (MPS) mechanism satisfies the stronger efficiency notion of lexi-efficiency, and is sd-envy-free under strict linear preferences and sd-weak-strategyproof under lexicographic preferences. We also prove that MPS can be characterized both by leximin-optimality and by item-wise ordinal fairness, and the family of eating algorithms which MPS belongs to can be characterized by lexi-efficiency.

A laser monitoring method was used to determine the mole-fraction solubility of naphazoline nitrate (NPZN) in ten mono-solvents namely “methanol (MeOH), ethylene glycol monomethyl ether (EGME), ethanol (EtOH), ethylene glycol monoethyl ether (EGEE), n-propanol (n-PrOH), ethylene glycol monopropyl ether (EGPE), isopropanol (i-PrOH), ethylene glycol (EG), ethylene glycol monobutyl ether (EGBE) and N,N-dimethylformamide (DMF)” at (278.15 ∼ 323.15) K and 0.1 MPa. Results suggested that NPZN solubility values exhibited an increasing trend at investigated temperature ranges. Simultaneously, experimental solubility of NPZH had a general order of “DMF > EGME > EG > MeOH > EGEE > EGPE > EtOH > EGBE > n-PrOH > i-PrOH”. Hirshfeld surface was employed to analyze and quantize the intermolecular interaction of NPZN during the crystal construction process. The impact of solute–solvent interaction on NPZN solubility was investigated by calculating the solvation free energies of solute in selected solvents through molecular dynamic (MD) simulation. It turned out that NPZN solubility was positively associated with solute–solvent interaction. Solubility values of NPZN were correlated by Wilson, NRTL, NRTL-SAC as well as UNIQUAC model, corresponding fitting accuracies of different model were in variation based on various root mean squared deviation (RMSD) and average relative deviation (ARD). The computational results indicated that UNIQUAC model performed the highest accuracy in correlation of experimental solubility. Finally, thermodynamic properties of dissolution process and mixing process were investigated by UNIQUAC model in this research work. The existences of negative Gibbs energy changes and positive entropy changes were observed, which suggested that the dissolution process and mixing process were always spontaneous and entropy-increasing.

In the current study, we developed a synergistic chemo-immunotherapy using doxorubicin (Dox) and a natural polysaccharide as immunomodulator. First, we isolated a polysaccharide (MPW) from the root of Lepidium meyenii Walp. (maca) and characterized its chemical properties. MPW contains → 4) -α-D-Glcp- (1 → glycosidic bonds, while the terminal α-D-Glcp- (1 → group is connected to the main chain through an O-6 bond. This polysaccharide was then modified by cationization (C-MPW) to enhance immunoregulatory activity. MPW and C-MPW were combined with Dox and their chemo-immunotherapy effects on 4T1 tumor-bearing mice were assessed. Results indicated that the combination of MPW/C-MPW exerted a stronger anti-tumor effect than Dox alone, while reducing systemic toxicity and inhibiting tumor metastasis. In addition, MPW and C-MPW exerted tumor immunotherapy effects through the NF-κB, STAT1, and STAT3 signaling pathways, redirecting TAMs to the M1 phenotype that facilitates immunological responses against tumors. As a result, the immunosuppressive tumor microenvironment was remodeled into an immune-activated state due to enhanced secretion of IL-12, TNF-α, and INF-γ. Moreover, C-MPW exerted a stronger immunomodulatory effect than MPW. In conclusion, MPW and its cationic derivative are promising tools for cancer immunotherapy.

This study isolated and characterized a novel polysaccharide (PNPS-0.3) from the residue of Panax notoginseng by gradient elution. PNPS-0.3 mainly consisted of a backbone of →4)- α-D-GalAp-(1 → 4-β-L-Rhap-1 → 4)-β-D-Galp-(1 → residues, with an α-L-Araf-1 → 5)-α-L-Araf-(1 → branch connecting to the backbone at O-3 of →4-β-L-Rhap-1 → and a molecular weight of 76,655 Da. Furthermore, the adjuvant potential of PNPS-0.3 with bone marrow dendritic cells (BMDCs) was investigated. The results suggested that PNPS-0.3 could induce maturation of BMDCs by reshaping the morphology, upregulating the CD40, CD80, CD86 and MHC II membrane phenotypic markers, and by promoting the secretion of TNF-α and IL-12 proinflammatory cytokines. Moreover, PNPS-0.3 can trigger the DC-induced T-cell immune response, as indicated by the higher expressions of CD4, CD8, CD69, and MHC II in T cells with increased secretion of INF-β. Furthermore, PNPS-0.3 can bind to the pattern recognition receptors (PRR) of Toll-like receptor 4 (TLR 4), Toll-like receptor 2 (TLR 2), and mannose receptor (MR) on BMDCs. PNPS-0.3 also upregulated the expressions of Myd88, IKKβ, PP65, T-P65, and NF-κB, suggesting that the TLR4/TLR2-NF-κB signaling pathway was involved in the immunomodulatory mechanism. In conclusion, the immunoadjuvant potential of novel PNPS-0.3 was characterized, which is beneficial for the future utilization and development of P. notoginseng.

It is extremely desired to develop cost-effective and high-efficient water oxidation electrocatalysts in alkaline electrolytes. In this Letter, we report the topotactic conversion of Cu(tetracyanoquinodimethane) nanoarray, denoted as Cu(TCNQ), into Fe(TCNQ)2 nanoarray via low-temperature cationic exchange. As a 3D electrode, such Fe(TCNQ)2 possesses superior oxygen evolution reaction (OER) performance needing overpotentials as low as 321 and 353 mV to afford 20 and 50 mA cm–2 in 1.0 M KOH, respectively. Remarkably enough, such a catalyst shows good durability in the long term electrochemical process with its catalytic activity being retained for 25 h at lowest. This work demonstrates that Fe(TCNQ)2 nanoarray may open up new possibilities for OER application.

In this investigation, innovative pH-sensitive and amphiphilic nanoparticles (NPs) were synthesized by grafting histidine (His, pH sensitive molecule) and stearic acid (SA, hydrophobic segment) onto the polysaccharides of Bletilla striata (BSP). The His-SA-BSP was able to self-assemble into NPs with pH sensitivity. The acidic conditions could trigger the imidazole ionization and reverse the surface charge, while the electrostatic repulsion wrecked the structure and drove the NPs to a swollen state, as revealed by dynamic light scattering (DLS), transmission electron microscopy (TEM), and critical micelle concentration (CMC) analyses. By increasing the degree of substitution (DS) of His, the NPs showed improved pH sensitivity. The NPs could accelerate Doxorubicin (Dox) release to a remarkably greater extent (3-fold) at pH 5 than at pH 7.4. The CCK-8 assay demonstrated a good biocompatibility of the NPs towards different cell lines and a specific inhibition effect of Dox-loaded NPs against tumor cells. Furthermore, the NPs showed the improved cellular uptake of Dox towards MCF-7 by fluorescence microscopy and flow cytometry. Therefore, the new His-SA-BSP showed potential applications in drug nanocarrier systems.

A microwave processing technology was applied to degrade saponins from the stems and leaves of Panax notoginseng. Six transformation products (1–6), named 20(S)-ginsenoside Rg3 (1), 20(R)-ginsenoside Rg3 (2), notoginsenoside SFt3 (3), ginsenoside Rk1 (4), ginsenoside Rg5 (5), and 20(S)-ginsenoside Rh2 (6) were isolated and identified from a microwave processed extract of the stems and leaves of P. notoginseng (MEL). This transformation method was also applied for producing the minor ginsenosides in flowers, seeds and pedicels of P. notoginseng. The extract and compounds 1–6 in MEL were evaluated in vitro for anticancer and anticoagulant activities. The results showed that the MEL extract and transformation products had outstanding inhibitory activities against human cervical cancer Hela and lung cancer A549 cells. The strongest inhibitory effect was observed for 20(S)-Rh2 (6) with an IC50 value of 8.23 μM in Hela cells. Moreover, the results showed that the MEL significantly prolonged prothrombin time in a concentration-dependent manner. The anticoagulant effect of the MEL improved with the increased contents of Rk1, Rg5, and SFt3.

NH3 synthesis heavily depends on the energy-intensive Haber–Bosch process, which produces serious carbon emission. Electrocatalytic N2 reduction emerges as an environmentally benign process for sustainable artificial N2 fixation but requires efficient, stable and selective catalysts for the N2 reduction reaction (NRR). Here, we report that Cr2O3 nanofiber behaves as a superb non-noble-metal NRR electrocatalyst for artificial N2 fixation to NH3, with excellent selectivity under ambient conditions. In 0.1 M HCl, this catalyst achieves a high Faradaic efficiency of 8.56% and a high NH3 formation rate of 28.13 μg h−1 mgcat.−1, placing it amongst the most active aqueous-based NRR electrocatalysts. Moreover, this catalyst also shows strong electrochemical durability during electrolysis and the recycling test. It opens a new avenue to explore the rational design of Cr-based nanostructures as advanced catalysts for N2 fixation and other applications.

It is extremely important to develop earth-abundant and stable oxygen evolution reaction (OER) electrocatalysts with excellent performance in alkaline media. In this work, we describe the in situ electrochemical conversion of microrod array of Ni(tetracyanoquinodimethane)2, Ni(TCNQ)2, into Ni(OH)2 nanoparticles embedded in a conductive TCNQ microrod array via anode oxidation. Such Ni(OH)2-TCNQ microarray shows OER activity needing overpotentials of 322 and 354 mV to attain current densities of 50 and 100 mA cm–2 in 1.0 M KOH, respectively. It is also extremely durable with its electrocatalytic performance being kept for at least 20 h. This work points out a stimulating approach to explore the utilization of TCNQ array as a conductive matrix for electrochemical applications.