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In this paper, the crystallization behavior of a novel poly(monothiocarbonate), poly(trimethylene monothiocarbonate) (PTMMTC), was investigated and compared with its polycarbonate analogue, poly(trimethylene carbonate) (PTMC). It is found that PTMMTC exhibits strong crystallizability, while unstretched PTMC is amorphous. DSC and DMA results reveal that PTMMTC possesses higher glass transition temperature (Tg) and β-transition temperature (Tβ) than PTMC. Simulation based on density functional theory (DFT) shows that, the bond angle of C-S-C is evidently smaller than that of C-O-C, and thus a larger dipole moment. This leads to the stronger intermolecular interaction and more rigid chain conformation in PTMMTC, which is the origin of sulfur-substitution enhanced crystallization. The crystal structure of PTMMTC was preliminarily determined for the first time. PTMMTC has an orthorhombic crystal structure with a planar zig-zag chain conformation. The parameters of unit cell are a = 10.74 A, b = 4.79 A, and c (fiber axis) = 7.74 A.

Calreticulin (Crt) is a highly conserved and multi-functional protein with lectin-like properties and important immunological activities. In this study, a Crt homolog, namely, ToCrt, was cloned and characterized from the obscure puffer Takifugu obscurus with an open reading frame of 1278 bp encoding a putative protein of 425 amino acids. The deduced amino acid sequence of ToCrt consisted of three conserved structural domains: N-domain, P-domain, and C-terminal domain. In the phylogenetic tree, ToCrt formed a separate cluster with three Crts from other pufferfish species (Takifugu rubripes, Takifugu flavidus, and Takifugu bimaculatus). The mRNA transcript of ToCrt was ubiquitously expressed in all the examined tissues in a decreasing order: liver, spleen, kidney, gills, intestine, and heart. After Vibrio harveyi, Edwardsiella tarda, and Aeromonas hydrophila stimulations, the levels of ToCrt mRNA in the kidney and spleen were significantly upregulated compared with that in the control group. The recombinant calreticulin domain of ToCrt (rToCrt) could bind three Gram-negative bacteria (V. harveyi, E. tarda, and A. hydrophila) and polysaccharides from bacterial cell walls such as lipopolysaccharide and peptidoglycan. Meanwhile, rToCrt could agglutinate different kinds of microorganisms and exhibit antimicrobial activity. These results suggested that T. obscurus ToCrt could serve as an antimicrobial effector in the host immune response against invading microorganisms.

Background. Previous studies have suggested a link between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD), yet long-term follow-up studies to elucidate this association are lacking. We aimed to identify the relationship between NAFLD and H. pylori in these people. Methods. A total of 2,934 adults between June 2013 and October 2017 were collected; among them, 675 people met the requirements. People were assessed for H. pylori infection diagnosis as detected by the carbon-13 urea breath test; they were also assessed for NAFLD diagnosis by ultrasound. Results. H. pylori infection was present in 206 patients (30.5%), and 469 (69.5%) participants were classified as controls. Participants with H. pylori infection had a higher rate of incident NAFLD than those who were uninfected (37/206; 18% versus 73/469; 15.6%) ( p < 0.001 ). Compared with the control group, the recovery rate of NAFLD in the H. pylori+ve group was low (6/206, 2.9% versus 33/469, 7.0%) ( p < 0.001 ). Besides, the incidence of uric acid, postprandial blood glucose, TG, LDL-C, HDL-C, and fasting plasma glucose was significantly different between the two groups ( p < 0.001 ), but no difference was found in alanine aminotransferase (ALT), liver-total protein, urea nitrogen, and cholesterol ( p > 0.05 ). Conclusion. H. pylori infection was a risk factor for NAFLD and affected the occurrence or reversal of NAFLD, indicating that H. pylori infection eradication might play a role in reducing the risk of NAFLD.

Integrated photonics enables signal synthesis, modulation and conversion using photonic integrated circuits (PICs). Many materials have been developed, among which silicon nitride (Si3N4) has emerged as a leading platform particularly for nonlinear photonics. Low-loss Si3N4 PICs have been widely used for frequency comb generation, narrow-linewidth lasers, microwave photonics and photonic computing networks. Yet, among all demonstrated functionalities for Si3N4 integrated photonics, optical non-reciprocal devices such as isolators and circulators have not been achieved. Conventionally, they are realized based on the Faraday effect of magneto-optic materials under an external magnetic field; however, it has been challenging to integrate magneto-optic materials that are not compatible with complementary metal-oxide-semiconductors and that require bulky external magnet. Here we demonstrate a magnetic-free optical isolator based on aluminium nitride (AlN) piezoelectric modulators monolithically integrated on low-loss Si3N4 PICs. The transmission reciprocity is broken by spatio-temporal modulation of a Si3N4 microring resonator with three AlN bulk acoustic wave resonators that are driven with a rotational phase. This design creates an effective rotating acoustic wave that allows indirect interband transition in only one direction among a pair of strongly coupled optical modes. A maximum of 10 dB isolation is achieved under 300 mW total radiofrequency power applied to three actuators, with minimum insertion loss of 0.1 dB. An isolation bandwidth of 700 MHz is obtained, determined by the optical resonance linewidth. The isolation remains constant over nearly 30 dB dynamic range of optical input power, showing excellent optical linearity. Our integrated, linear, magnetic-free, electrically driven optical isolator could be a key building block for integrated lasers and optical interfaces for superconducting circuits., An electrically driven, magnetic-free optical isolator is demonstrated. The device, based on aluminium nitride piezoelectric modulators and a silicon nitride microring resonator, may be useful for integrated lasers and other opto-electric systems.

An unacceptable increase in antibacterial resistance has arisen due to the abuse of multiple classes of broad-spectrum antibiotics. Therefore, it is significant to develop new antibacterial agents, especially those that can accurately identify and kill specific bacteria. Herein, we demonstrate a kind of perilla-derived carbon nanodots (CNDs), integrating intrinsic advantages of luminescence and photodynamic, providing the opportunity to accurately identify and kill specific bacteria. The CNDs have an exotic-doped and π-conjugated core, vitalizing them near-infrared (NIR) absorption and emission properties with photoluminescence quantum yield of 21.1%; hydrophobic chains onto the surface of the CNDs make them to selectively stain Gram-positive bacteria by insertion into their membranes. Due to the strong absorption in NIR region, reactive oxygen species are in situ generated by the CNDs onto bacterial membranes under 660 nm irradiation, and 99.99% inactivation efficiency against Gram-positive bacteria within 5 min can be achieved. In vivo results demonstrate that the CNDs with photodynamic antibacterial property can eliminate the inflammation of the area affected by methicillin-resistant Staphylococcus aureus (MRSA), and enabling the wound to be cured quickly.

Silicon photonics enables wafer-scale integration of optical functionalities on chip. Silicon-based laser frequency combs can provide integrated sources of mutually coherent laser lines for terabit-per-second transceivers, parallel coherent light detection and ranging, or photonics-assisted signal processing. We report heterogeneously integrated laser soliton microcombs combining both indium phospide/silicon (InP/Si) semiconductor lasers and ultralow-loss silicon nitride (Si3N4) microresonators on a monolithic silicon substrate. Thousands of devices can be produced from a single wafer by using complementary metal-oxide-semiconductor-compatible techniques. With on-chip electrical control of the laser-microresonator relative optical phase, these devices can output single-soliton microcombs with a 100-gigahertz repetition rate. Furthermore, we observe laser frequency noise reduction due to self-injection locking of the InP/Si laser to the Si3N4 microresonator. Our approach provides a route for large-volume, low-cost manufacturing of narrow-linewidth, chip-based frequency combs for next-generation high-capacity transceivers, data centers, space and mobile platforms.

Efficacious regulation of the geometric and electronic structures of carbon nanomaterials via the introduction of defects and their synergy is essential to achieving good electrochemical performance. However, the guidelines for designing hybrid materials with advantageous structures and the fundamental understanding of their electrocatalytic mechanisms remain unclear. Herein, superfine Pt and PtCu nanoparticles supported by novel S,N-co-doped multi-walled CNT (MWCNTs) were prepared through the innovative pyrolysis of a poly(3,4-ethylenedioxythiophene)/polyaniline copolymer as a source of S and N. The uniform wrapping of the copolymer around the MWCNTs provides a high density of evenly distributed defects on the surface after the pyrolysis treatment, facilitating the uniform distribution of ultrafine Pt and PtCu nanoparticles. Remarkably, the Pt1Cu2/SN-MWCNTs show an obviously larger electroactive surface area and higher mass activity, stability, and CO poisoning resistance in methanol oxidation compared to Pt/SN-MWCNTs, Pt/S-MWCNTs, Pt/N-MWCNTs, and commercial Pt/C. Density functional theory studies confirm that the co-doping of S and N considerably deforms the CNTs and polarizes the adjacent C atoms. Consequently, both the adsorption of Pt1Cu2 onto the SN-MWCNTs and the subsequent adsorption of methanol are enhanced; in addition, the catalytic activity of Pt1Cu2/SN-MWCNTs for methanol oxidation is thermodynamically and kinetically more favorable than that of its CNT and N-CNT counterparts. This work provides a novel method to fabricate high-performance fuel cell electrocatalysts with highly dispersed and stable Pt-based nanoparticles on a carbon substrate.

To identify the effect of solvents and anthracene on the purification of carbazole, the solvent crystallization of carbazole was investigated with xylene, chlorobenzene and tetrachloroethylene (TCE) as solvents under two forced circulation cooling (FCC) modes. The co-crystalline experimental data were obtained from runs carried out at different anthracene levels between 1% (mass) and 10% (mass). The results showed that a uniform flake carbazole crystal obtained when using xylene and chlorobenzene under the FCC-1 mode with gradual cooling rate. Nevertheless, fine flake crystals grown under shock cooling of FCC-2 mode. It is beneficial to improving the purity of carbazole with chlorobenzene as solvent under cooling mode of FCC-1. Anthracene could promote the growth of carbazole in solution, and it has a significant influence on the purification of carbazole.

Mei Liu,1,2 Rui-Bo Wang,1 Jian-Hong Xing,2 Ying-Xue Tang3 1Chinese Medicine College, Shandong University of Traditional Chinese Medicine, Jinan, 250355, Shandong, People’s Republic of China; 2Department of Obstetrics, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250011, Shandong, People’s Republic of China; 3Postgraduate Department, Shandong University of Traditional Chinese Medicine, Jinan, 250355, ShandongCorrespondence: Ying-Xue TangPostgraduate Department, Shandong University of Traditional Chinese Medicine, Changqing Campus of Shandong University of Traditional Chinese Medicine, Jinan, 250355, Shandong, People’s Republic of ChinaTel +8653189628067Email doctortyx@163.comBackground: Preeclampsia (PE), a serious pregnancy disorder, is responsible for maternal and fetal mortality worldwide. At present, numerous candidate biomarkers have been studied to predict PE.Objective: To explore the role of Corin in PE risk prediction and then evaluate the predictive ability of soluble vascular endothelial growth factor receptor-1 (sFlt-1), placenta growth factor (PLGF), and sFlt-1/PLGF after the addition of Corin.Methods: A total of 135 pregnant women from Affiliated Hospital of Shandong University of Traditional Chinese Medicine participated in this study in their first trimester. A nested case–control study was conducted and all subjects were divided into PE groups (n=46) and controls (n=89). The levels of PLGF, sFlt-1, sFlt-1/PLGF ratio, and Corin of the two groups at 12– 16 weeks of gestation were measured and analyzed. Receiver operating characteristic (ROC) curve, net reclassification index (NRI) and integrated discrimination index (IDI) were calculated to evaluate the predictive ability of various biomarkers.Results: The concentrations of sFlt-1, sFlt-1/PLGF, and Corin in PE group were significantly higher than that in controls, while the concentration of PLGF in the PE group was lower. The area under curve (AUC) of sFlt-1, PLGF and sFlt-1/PLGF for predicting PE was 0.786, 0.719 and 0.866, respectively. Combined with Corin, the prediction ability of the above biomarkers could be improved to 0.876, 0.847, and 0.897, respectively. Corin in combination with sFlt-1/PLGF resulted in improvements with 12.6% being reclassified and a resulting NRI of 0.142 (0.020∼ 0.263) and IDI of 0.087 (0.037∼ 0.137).Conclusion: The addition of Corin to sFlt-1, PLGF and sFlt-1/PLGF can improve the ability of each marker to predict PE risk. Corin in combination with sFlt-1/PLGF can be used as ideal markers to identify the pregnant women who subsequently develop PE, which will help in risk stratification and better therapeutic management.Keywords: preeclampsia, Corin, soluble vascular endothelial growth factor receptor-1, placental growth factor, prediction

It has been confirmed that the new coronavirus SARS-CoV-2 caused the global pandemic of coronavirus disease 2019 (COVID-19). Studies have found that 3-chymotrypsin-like protease (3CLpro) is an essential enzyme for virus replication, and could be used as a potential target to inhibit SARS-CoV-2. In this work, 3CLpro was used as the target to complete the high-throughput virtual screening of the FDA-approved drugs, and Indinavir and other 10 drugs with high docking scores for 3CLpro were obtained. Studies on the binding pattern of 3CLpro and Indinavir found that Indinavir could form the stable hydrogen bond (H-bond) interactions with the catalytic dyad residues His41-Cys145. Binding free energy study found that Indinavir had high binding affinity with 3CLpro. Subsequently, molecular dynamics simulations were performed on the 3CLpro and 3CLpro-Indinavir systems, respectively. The post-dynamic analyses showed that the conformational state of the 3CLpro-Indinavir system transformed significantly and the system tended to be more stable. Moreover, analyses of the residue interaction network (RIN) and H-bond occupancy revealed that the residue-residue interaction at the catalytic site of 3CLpro was significantly enhanced after binding with Indinavir, which in turn inactivated the protein. In short, through this research, we hope to provide more valuable clues against COVID-19.

Recently, interest in lithium–sulfur batteries has surged due to rapid advances in energy-intensive electric devices. However, despite the high theoretical capacity, natural abundance, and environm...

Context Laurolitsine is an aporphine alkaloid and exhibits potent antihyperglycemic and antihyperlipidemic effects in ob/ob mice. Objective To investigate the pharmacokinetics, tissue distribution and excretion of laurolitsine. Materials and methods A LC-MS/MS method was established and validated to determine laurolitsine concentrations in the biological matrix of rats (plasma, tissue homogenate, urine and faeces). 10 Sprague-Dawley (SD) rats were used for plasma exposure study: 5 rats were injected with 2.0 mg/kg of laurolitsine via the tail vein, and the other 5 rats were administered laurolitsine (10.0 mg/kg) by gavage. 25 SD rats used for tissue distribution study and 5 SD rats for urine and faeces excretion study: rats administered laurolitsine (10.0 mg/kg) by gavage. After administered, serial blood, tissue, urine and faeces were collected. Analytical quantification was performed by a previous LC-MS/MS method. The pharmacokinetics, bioavailability, tissue distribution and excretion of laurolitsine were described. Results The pharmacokinetic parameters of oral and intravenous administration with Tmax were 0.47 and 0.083 h, t1/2 were 3.73 and 1.67 h, respectively. Oral bioavailability was as low as 18.17%. Laurolitsine was found at a high concentration in the gastrointestinal tract, liver, lungs and kidneys (26 015.33, 905.12, 442.32 and 214.99 ng/g at 0.5 h, respectively) and low excretion to parent laurolitsine in urine and faeces (0.03 and 1.20% in 36 h, respectively). Conclusions This study established a simple, rapid and accurate LC-MS/MS method to determine laurolitsine in different rat samples and successful application in a pharmacokinetic study.

In this study, we reported the covalent post-synthetic modification (PSM) of a luminescent complex to achieve aggregation-induced emission (AIE), prepared using the Schiff base reaction of TPE–CHO and HLC–NH2, denoted by HLC–NH2–TPE. HLC–NH2 formed a 2D luminescent complex which was constructed using 4,4′-diamino-[1,1′-biphenyl]-2,2′-dicarboxylic acid and zinc ions via a solvothermal reaction. HLC–NH2–TPE inherited the luminescence properties of HLC–NH2 and exhibited noticeable AIE properties in response to environmental viscosities and temperature changes. Interestingly, HLC–NH2–TPE displayed a time-dependent luminescence conversion phenomenon in a mixed solution of DMF/H2O (v : v/1 : 9).

Discovering efficient and low CO selectivity non-noble heterogeneous catalysts toward formic acid (FA) dehydrogenation is vital for H2 energy systems. As a heating temperature is required to activate this reaction, the strategy of coupling a FA dehydrogenation reactor with a photothermal system possesses great potential for industrial applications. Herein, a sophisticated catalyst, a Mo1.98C1.02 porous film supported on carbon fiber paper, is demonstrated, with the advantages of a porous nanostructure, small nanoparticles and a carbon-supported structure simultaneously. The composite exhibits prominent thermal catalytic FA dehydrogenation, with a CO-free H2 generation rate of 0.79 L g−1 h−1 at 100 °C. Density functional theory calculations show that the formate route (*OCHOH → *OCOH + 1/2H2 → *OCO + 1/2H2 → CO2) is the minimum energy path for H2 and CO2 formation. Besides, a photothermal device was designed based on Bi2Te3/Cu, which can absorb and convert 1 kW m−2 irradiation into a high temperature of 240 °C, due to the high sunlight absorption, low heat conduction and low heat irradiation. Thus, a sunlight-driven thermal catalytic system was designed based on this device, with a H2 generation rate of 1.07 L g−1 h−1 under 0.25 kW m−2. This value is about two orders of magnitude faster than that of photocatalytic FA decomposition over reported non-precious photocatalysts. These results demonstrate that FA dehydrogenation can be realized under weak solar irradiation with the assistance of photothermal systems, facilitating industrial applications.

Tanshinones are the bioactive nor-diterpenoid constituents of the Chinese medicinal herb Danshen (Salvia miltiorrhiza). These groups of chemicals have the characteristic furan D-ring, which differentiates them from the phenolic abietane-type diterpenoids frequently found in the Lamiaceae family. However, how the 14,16-epoxy is formed has not been elucidated. Here, we report an improved genome assembly of Danshen using a highly homozygous genotype. We identify a cytochrome P450 (CYP71D) tandem gene array through gene expansion analysis. We show that CYP71D373 and CYP71D375 catalyze hydroxylation at carbon-16 (C16) and 14,16-ether (hetero)cyclization to form the D-ring, whereas CYP71D411 catalyzes upstream hydroxylation at C20. In addition, we discover a large biosynthetic gene cluster associated with tanshinone production. Collinearity analysis indicates a more specific origin of tanshinones in Salvia genus. It illustrates the evolutionary origin of abietane-type diterpenoids and those with a furan D-ring in Lamiaceae., Salvia miltiorrhiza is a medicinal plant that can produce the bioactive tanshinones. Here, the authors report the improved genome assembly and reveal the possible roles of three CYP71Ds in catalyzing the reactions leading to the formation of the characteristic furan D-ring of transhinones.

The application of Pt alloy catalysts for oxygen reduction reactions (ORRs) in proton-exchange membrane fuel cells is severely impeded by base metal leaching, since the produced metal ions can resu...

Discovering efficient and promising non-noble catalysts toward the alkaline hydrogen evolution reaction (HER) is vital for a clean energy system. Here, we design an efficient alkaline HER electroca...

In this work, poly(ionic liquid) (PIL)-containing block copolymers (BCPs), poly(ethylene oxide)-b-poly(1-((2-acryloyloxy)ethyl)-3-docosylimidazolium) with different counterions (PEO-b-P(AOEDIm-X), ...

To explore the characteristics and prognostic significance of genetic mutations in acute myeloid leukemia (AML), we screened the gene mutation profile of 171 previously untreated AML patients using a next‐generation sequencing technique targeting 127 genes with potential prognostic significance. A total of 390 genetic alterations were identified in 149 patients with a frequency of 87.1%. Younger age and high sensitivity to induction chemotherapy were associated with a lower number of mutations. NPM1 mutation was closely related to DNMT3A and FLT3‐internal tandem duplication (FLT3‐ITD) mutations, but mutually exclusive with ASXL1 mutation and CEBPA double mutation. In univariate analysis, ASXL1 or TET2 mutation predicted shorter overall survival (OS) or relapse‐free survival (RFS), DNMT3A, FLT3‐ITD, or RUNX1 mutation predicted a higher likelihood of remission‐induction failure, whereas NRAS mutation or CEBPA double mutation predicted longer OS. Concurrent DNMT3A, FLT3‐ITD, and NPM1 mutations predicted shorter OS. Hypomethylation agents could improve the OS in patients with DNA methylation‐related mutations. According to multivariate analysis, TET2 mutation was recognized as an independent prognostic factors for RFS. In summary, our study provided a detailed pattern of gene mutations and their prognostic relevance in Chinese AML patients based on targeted next‐generation sequencing screening., Genetic mutations can predict favorable or unfavorable prognosis of AML patients. Allo stem cell transplantation can provide benefits for AML patients with bad genetic mutations.

In this paper, the effect on the properties of alumina/aluminum cermet by changing the sintering temperature, and comparing the advantages and disadvantages of different characterization methods and their application range, it provides a reference for selecting the characterization technology suitable for alumina/aluminum composites.Through mixing, molding, sintering, sample preparation, scanning electron microscopic observation, energy spectrometer observation and analysis, the following conclusions can be drawn: the higher the vacuum sintering temperature, the more aluminum material is melted out of the body to form aluminum balls on the surface, and the green body The more severe the cracking. When the sample is sintered at a temperature of 600 °C, the density is the highest and the appearance is the best. When the molding pressure is 40 MPa and the sintering temperature is 700 °C, the microstructure of the sintered alumina/aluminum cermet is better. It can be seen from SEM and EDS analysis that the particles are continuously distributed and the larger one is metal Al, and the particles are discontinuously distributed and finer is Al2O3.

In this study, a knee osteoarthritis (KOA) rat model induced by monosodium iodoacetate (MIA) was used to study the effect of moxibustion on improving knee cartilage damage and its effect on the intestinal flora. The experimental rats were divided into the normal group (N), model group (M), moxibustion treatment group (MS), and diclofenac sodium treatment group (DS). After 4 weeks, cartilage pathological damage in the knee joint was evaluated using hematoxylin-eosin and safranin O-fast green staining analysis. ELISAs and Western blots were used to detect the expression levels of IL-1β and TNF-α in the serum and cartilage, respectively. The total DNA of the fecal samples was extracted and subjected to high-throughput sequencing of the V3-V4 region of the 16S rRNA gene to analyze the changes in the intestinal flora. In the model group, the cartilage was obviously damaged, the expression levels of IL-1β and TNF-α in the serum and cartilage were increased, and the abundance and diversity of the intestinal flora were decreased. Moxibustion treatment significantly improved the cartilage damage and reduced the concentration of inflammatory factors in the serum and cartilage. The high-throughput sequencing results showed that compared to the model group, the moxibustion treatment regulated some specific species in the intestinal microorganisms rather than the α diversity. In conclusion, our findings suggest that moxibustion treatment may work through two aspects in rats. On one hand, it directly acts on knee cartilage to promote repair, and on the other hand, it regulates the composition of the intestinal flora and reduces the production of inflammatory factors.

Recent advances in the synthesis of block copolymers have enabled the creation of smart and functional designer polymers possessing specific intermolecular interactions. The long-range nature of these interactions strongly affects the molecular packings and microstructures of such polymers, which are intimately related to their properties. In addition to various applications, their unique physicochemical properties, distinguished from conventional block copolymers, are attracting significant attention from polymer and materials scientists. In this review, we describe the current understanding of the structure-property relationship of block copolymers having long-range interactions and suggest possible directions of technological development. We particularly focus on how specific interactions, such as Coulombic, π-π stacking, hydrogen-bonding, and metal/ion-dipole interactions, affect the molecular arrangements of block copolymers on the nanometer and molecular scales. Such information could lead to block copolymers with more advanced functions for future nanotechnologies.

Sanguisorba officinalis L. (family Rosaceae, subfamily Rosoideae) is a plant found throughout Southern Europe, Northern Africa, and Eastern Asia. This study demonstrated the antibacterial activity of a purified polyphenolic extract (PPE) from S. officinalis L. against Bacillus subtilis using growth inhibitory and apoptosis assays, and investigated the antibacterial mechanism responsible for changes in cell membrane properties. Fourier transform infrared spectroscopy suggested that PPE altered the cell wall and membrane properties of B. subtilis. Further determination of cell membrane integrity and permeability revealed that B. subtilis membrane integrity was more severely damaged by PPE at the minimum inhibitory concentration (MIC) than at the minimum bactericidal concentrati on (MBC). Instead, PPE at the MBC reduced cell membrane fluidity by significantly decreasing the proportion of anteiso- and iso-branched phospholipid fatty acids (PLFAs) from 64.17 ± 0.28% and 27.23 ± 0.03% in the control to 5.57 ± 1.06% and 6.00 ± 1.40%, respectively (P

In this work, a bimetallic catalyst of Pd and Ni supported on HZSM-5 was designed and evaluated in the hydrodeoxygenation of model compounds representing various C–O bonds in lignin. The effects of temperature, holding time, and initial H2 pressure on the catalytic performance of the Pd–Ni/HZSM-5 catalyst were investigated. The results indicated that the Pd–Ni/HZSM-5 catalyst exhibited superior catalytic activity towards the conversion of the model compounds to alkanes compared to its monometallic counterparts. Direct cleavage of the C–O bond in DPE was achieved under low H2 pressure, mainly producing benzene and minor amounts of phenol and cyclohexane, while at high H2 pressure, the reaction pathway was altered towards hydrogenation of the benzene ring, followed by then cleavage of the C–O bond to afford only cyclohexane. Moreover, the Pd–Ni/HZSM-5 catalyst showed high activities when applying other substrates including anisole, veratrole, guaiacol, benzyloxybenzene, phenethyl phenyl ether, and dibenzyl ether.

Recently, lower disorder-to-order transition (LDOT) phase behavior was observed in the poly(ionic liquid) (PIL)-containing block copolymers, poly(ethylene oxide)-b-poly(1-((2-acryloyloxy) ethyl)-3-...

The Diels-Alder reaction is one of the most powerful and widely used methods in synthetic chemistry for the stereospecific construction of carbon-carbon bonds. Despite the importance of Diels-Alder reactions in the biosynthesis of numerous secondary metabolites, no naturally occurring stand-alone Diels-Alderase has been demonstrated to catalyse intermolecular Diels-Alder transformations. Here we report a flavin adenine dinucleotide-dependent enzyme, Morus alba Diels-Alderase (MaDA), from Morus cell cultures, that catalyses an intermolecular [4+2] cycloaddition to produce the natural isoprenylated flavonoid chalcomoracin with a high efficiency and enantioselectivity. Density functional theory calculations and preliminary measurements of the kinetic isotope effects establish a concerted but asynchronous pericyclic pathway. Structure-guided mutagenesis and docking studies demonstrate the interactions of MaDA with the diene and dienophile to catalyse the [4+2] cycloaddition. MaDA exhibits a substrate promiscuity towards both dienes and dienophiles, which enables the expedient syntheses of structurally diverse natural products. We also report a biosynthetic intermediate probe (BIP)-based target identification strategy used to discover MaDA.

Thermal degradation of the composite constituted by high density polyethylene (HDPE) and microencapsulated red phosphorus (MRP) were studied using thermogravimetric (TG) data obtained at different heating rates. The kinetic models and parameters of the thermal degradation of MRP/HDPE composite were evaluated by FWO, KAS and IKP method. It indicates that the activation energy E of 4 % MRP/HDPE composite is higher than HDPE for three methods. MRP could improve the thermal stability and slow down the thermal degradation of HDPE. With adding MRP, the degradation mechanism of HDPE is changed and the degradation rate decreases.

Polyesters, as a class of high-performance and versatile polymer materials, often suffer from some drawbacks, such as hydrophobicity and brittleness due to their single structure nature. Thus, modifications have attracted much attention for enhancing their desirable properties, of which one efficient way is incorporating the aliphatic polyether segment into the main chain of the polyester. However, this approach is of much challenge because the obtained polyesters are problematic in either low alternating degree or low molecular weight. Herein, we describe an efficient strategy to incorporate polyether fragment into polyester by developing a novel Co-Al based heterodinuclear complex for mediating the copolymerization of propylene oxide (PO) with e-caprolactone (CL). The tracking experiments reveal that PO and CL convert into the polymer chain throughout the polymerization process. Especially, the linear increase in the molecular weight with conversion of CL indicates the controllable nature of the copolymerization. The competition polymerization, offering the monomer reactivity ratios of rCL = 0.96 and rPO = 1.04, suggests that the tendency of self-propagation or incorporation of monomers is nearly identical. Interestingly, the obtained polymers with different ether contents exhibit tunable thermal properties with enhanced decomposition temperature for the polymer with higher ether content. The newly developed heterodinuclear complex for new polymerization provides an idea to synthesize new functional polymeric materials.

Advances in lithium battery technologies necessitate improved energy densities, long cycle lives, fast charging, safe operation, and environmentally friendly components. This study concerns lithium-organic batteries comprising bioinspired poly(4-vinyl catechol) (P4VC) cathode materials and single-ion conducting polymer nanoparticle electrolytes. The controlled synthesis of P4VC results in a two-step redox reaction with voltage plateaus at around 3.1 and 3.5 V, as well as a high initial specific capacity of 352 mAh g-1 . The use of single-ion nanoparticle electrolytes enables high electrochemical stabilities up to 5.5 V, a high lithium transference number of 0.99, high ionic conductivities, ranging from 0.2×10-3 to 10-3 S cm-1 , and stable storage moduli of >10 MPa at 25-90 °C. Lithium cells can deliver 165 mAh g-1 at 39.7 mA g-1 for 100 cycles and stable specific capacities of >100 mAh g-1 at a high current density of 794 mA g-1 for 500 cycles. As the first successful demonstration of solid-state single-ion polymer electrolytes in environmentally benign and cost-effective lithium-organic batteries, this work establishes a future research avenue for advancing lithium battery technologies.

Porous covalent organic frameworks (COFs), as an emerging material, have the characteristics of high stability, large series of components, easy synthesis, modification, and adjustable amplitude. They have the potential to become good catalysts. Bromine, as a halogen, has attracted intensive interest for the modification of photocatalysts for photocatalytic reactions. It is feasible to enhance the activity and selectivity of the material by facile functionalization of the reticular parent structure's electron-withdrawing groups. In addition, the conjugation effect of bromine, further delocalizing the electrons of the COF, is beneficial to the progress of many photocatalytic reactions. Reports on the modification of COFs by bromine functional groups to improve the catalytic performance have not been found so far. Here, TAPP [5,10,15,20-tetrakis(4-aminophenyl)porphyrin] and 2,5-dibromo-1,4-benzenedialdehyde instead of terephthalaldehyde were chosen to synthesize a porphyrin-based COF (TAPBB-COF) by the solvothermal method. As expected, the valence band (VB) of TAPBB-COF is thus adjusted to a more suitable position. Additionally, the CO production when using TAPBB-COF under full-wavelength light for 12 h was 295.2 μmol g-1 , which was three times that of COF-366, and the new material has good recycling stability and selectivity (95.6 %). Theoretical calculations indicate that the nitrogen of the porphyrin ring and the Schiff base, and the bromine in TAPBB-COF contribute greatly to the activation of H2 O and the conversion of CO2 in the photoreaction.

Low aromaticity and a large number of oxygen-bridged bonds among the aromatic structural units of lignin make it possible to obtain chemicals directly. A novel Co/C@N catalyst with high activity towards hydrogenolysis of lignin-derived aryl ethers was synthesized according to the pyrolysis process of a predesigned ZIF-67. According to the results of characterization by powder X-ray diffraction (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), Co was reduced by the carbonized organic linker of ZIF-67, and N was doped into the carbon skeleton of the catalyst. The effects of holding time, temperature, and initial H2 pressure on the catalytic performance of Co/C@N were evaluated in the selective hydrogenolysis of benzyl phenyl ether (BPE). BPE was completely converted and the selectivity of monomer reached to 98.2% under optimized reaction conditions. The Calk-O bond in BPE was first dissociated to form toluene and phenol, and then phenol was rapidly hydrogenated to form cyclohexanol. Furthermore, the Co/C@N catalyst shows high activity for hydroprocessing and selective cleavage of other lignin-derived aryl ethers, including phenylethyl phenyl, diphenyl ether, dibenzyl ether, dinaphthalene ether, guaiacol, anisole and veratrole.

With the aggravation of soil acidification, aluminum toxicity has become one of the important stress factors that affect crop seed germination quality and crop yield. There have been many reports on QTL mapping and candidate gene screening for aluminum tolerance related traits in crops, but few reports on QTL mapping for aluminum tolerance during germination in Brassica napus L. The seed germination test was conducted on the recombinant inbred line population treated with 80 µg mL-1 aluminum solution and with distilled water as control. Germination potential was investigated at 3 d, germination rate was investigated at 7 d, root length, bud length and dry weight were measured, and the relative values of various characters were calculated. Based on 6K SNP chip and combined with high density genetic linkage map, we detected 23 QTLs for five traits in rape germination period. QTLs for relative germination potential, relative germination rate, relative root length, relative bud length and relative dry weight were 9, 1, 4, 5, and 4 respectively, covering A and C genomes, with LOD values from 3.00 to 5.26, and interpretable phenotypic variation from 7.70% to 13.10%. According to the confidence interval sequence of each QTL, 30 candidate genes related to aluminum stress were screened. ALMT1 gene and MATE gene are related to the synthesis and secretion of organic acids, which mainly enhance the aluminum tolerance of plants through the secretion of organic acids such as malic acid, citric acid and oxalic acid. STOP1 gene, NAC gene and RAP2.4 gene all belong to transcription activation factors, which enhance the resistance of plants by inducing the expression of aluminum tolerance genes. ABC transporter, membrane protein transporter, GDSL lipase enhance aluminum tolerance of plants by reducing accumulation of toxic substances on plasma membrane or discharging toxic substances out of body. Peroxidase and cytochrome P450 are genes related to oxidative stress, which have the functions of preventing oxidative damage of plant cells and resisting stress. At the same time, many genes encoding stress proteins were found, which play an important role in various stress reactions. The results of this study provide a theoretical basis for the cultivation of aluminum-tolerant rape varieties and the functional research of subsequent genes.

Dayan lignite was subjected to thermal dissolution sequentially with cyclohexane, acetone, and methanol. Each thermal dissolution extract was subjected to further separation/enrichment using column chromatography, which was sequentially eluted with petroleum ether, a mixture of ethyl acetate and petroleum ether (vol:vol = 1:1), and ethyl acetate. The three thermal dissolution extracts and nine enrichment subfractions were characterized by an Orbitrap mass spectrometry equipped with an atmospheric pressure chemical ionization ion source. The mass spectrometry data were also statistically analyzed by principal component analysis, which can reduce the dimensionality of data and classify multiple samples according to principal components. Identified compounds in the extracts and subfractions are classified into eight classes according to the heteroatom distribution. Hydrocarbon class is mainly presented in the petroleum ether fraction, and oxygen class, nitrogen class, and oxygen-nitrogen class are distributed in both petroleum ether/ethyl acetate and ethyl acetate subfractions. The combination of different analytical methods enhances the understanding of coal at the molecular level and provides important data for downstream refining processes.

Gemcitabine (Gem) is currently used as the first-line therapy for liver and pancreatic cancer but has limited efficacy in most cases. Dexamethasone (Dex) have been applied as a chemoprotectant and chemosensitizer in cancer chemotherapy. This study further explored the potential of combination of Gem and Dex and tested the hypothesis that glucocorticoid receptor signaling is essential for the synergistic antitumor activity. In the HepG2 and AsPC-1 xenograft models, the combination treatment showed a significantly synergistic antitumor activity. Immunohistochemistry of post-treatment tumors showed a significant decrease in proliferation and angiogenesis as compared to either of the treatments alone. Dex alone and the combination with Gem inhibited the expression of glucocorticoid receptor. The combination of Dex and Gem showed synergistic cytotoxicity in cell lines in vitro. The antiproliferative synergism is prevented by used glucocorticoid receptor (GR) small interfering RNA, demonstrating that the glucocorticoid receptor is required for the antiproliferative synergism of Gem and Dex. The inhibition of glucocorticoid receptor signaling pathway and induction of apoptosis via activation of caspases 3, 8 and 9, PARP, contributed to the synergistic effect of this combination therapy. These results demonstrate that Dex could potentiate the antitumor efficacy of Gem. The synergistic antitumor activity of the combination of Dex and Gem was through glucocorticoid receptor signaling. Taken together, a combination of Dex and Gem shows a significant synergistic antitumor activity and lesser toxicity both in vitro and in vivo and could be a combination chemotherapy for the treatment of highly expression of glucocorticoid receptor patients.

Trimethylamine-N-oxide (TMAO) is a gut microbial metabolite that promotes Alzheimer’s disease (AD) progression. Given that probiotics can alleviate AD symptoms by inhibiting the synthesis of TMAO, here we investigated the correlation between TMAO and cognitive deterioration by measuring TMAO levels in the plasma of choline-treated APP/PS1 mice (an AD mouse model) with and without probiotic treatments. We found that declines in L. plantarum in the gut were associated with cognitive impairment. Moreover, 12-weeks of treatment with memantine plus L. plantarum ameliorated cognitive deterioration, decreased Αβ levels in the hippocampus, and protected neuronal integrity and plasticity. These effects were accompanied by reductions in TMAO synthesis and neuroinflammation. These experiments demonstrate that L. plantarum augments the beneficial therapeutic effects of memantine treatment in APP/PS1 mice by remodeling the intestinal microbiota, inhibiting the synthesis of TMAO, and reducing clusterin levels. Our results thus highlight intestinal microbiota as a potential therapeutic target to decrease the risk of AD.

Porous interconnected carbon nanosheets (PICNs) with high electrochemical performance were prepared by doping urea and a co-hydrothermal precursor derived from soybean stalk (SS) and nickel nitrate. The specific surface area and average pore diameter of the as-synthesized PICNs are 2226.29 m2 g−1 and 1.89 nm, and their N and O contents are 5.08% and 9.4%, respectively, which is beneficial for increasing pseudocapacitance. Furthermore, the doping of the metal Ni increases the graphitization degree of the PICNs and promotes the conversion of pyridine-N to graphitized-N. Therefore, the PICNs possess a high specific capacitance of 407 F g−1 at a current density of 0.5 A g−1, a high capacitance retention of 78.62% even at 20 A g−1, and an outstanding cycling stability (over 93% retention rate after 10,000 charge/discharge cycles). Moreover, an energy density of 36.11 W h kg−1 is achieved at a power density of 517.8 W kg−1 during a two-electrode system test, and a retention rate of 87.5% is obtained after 10,000 cycles. This co-hydrothermal treatment as well as nitrogen-doping approach for preparing porous interconnected carbon from SS not only represents an alternative strategy for carbon-based supercapacitor materials but also provides a new option for the utilization of waste SS.

Infection by human immunodeficiency virus type 1 (HIV-1) not only destroys the immune system bringing about acquired immune deficiency syndrome (AIDS), but also induces serious neurological diseases including behavioral abnormalities, motor dysfunction, toxoplasmosis, and HIV-1 associated dementia. The emergence of HIV-1 multidrug-resistant mutants has become a major problem in the therapy of patients with HIV-1 infection. Focusing on the wild type (WT) and G48T/L89M mutated forms of HIV-1 protease (HIV-1 PR) in complex with amprenavir (APV), indinavir (IDV), ritonavir (RTV), and nelfinavir (NFV), we have investigated the conformational dynamics and the resistance mechanism due to the G48T/L89M mutations by conducting a series of molecular dynamics (MD) simulations and free energy (MM-PBSA and solvated interaction energy (SIE)) analyses. The simulation results indicate that alterations in the side-chains of G48T/L89M mutated residues cause the inner active site to increase in volume and induce more curling of the flap tips, which provide the main contributions to weaker binding of inhibitors to the HIV-1 PR. The results of energy analysis reveal that the decrease in van der Waals interactions of inhibitors with the mutated PR relative to the wild-type (WT) PR mostly drives the drug resistance of mutations toward these four inhibitors. The energy decomposition analysis further indicates that the drug resistance of mutations can be mainly attributed to the change in van der Waals and electrostatic energy of some key residues (around Ala28/Ala28' and Ile50/Ile50'). Our work can give significant guidance to design a new generation of anti-AIDS inhibitors targeting PR in the therapy of patients with HIV-1 infection.

A highly efficient Ni/N–C catalyst was synthesized by facile pyrolysis of a Ni-containing metal–organic framework (Ni-MOF), and its catalytic hydrogenolysis performance towards C–O bonds in lignin was evaluated in detail using diphenyl ether (DPE) as a model compound. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that the flower-like nanosheets of the Ni-MOF shrink, forming a loose and ordered spherical structure during pyrolysis. Under the optimal conditions, DPE was completely converted and the selectivity to monomers (benzene, cyclohexanol and cyclohexane) reached 99.1%. During the catalytic hydrogenolysis conversion (CHC) of DPE, the direct cleavage of the Caromatic–O bond affording benzene and phenol is the major reaction pathway, and a low H2 pressure is crucial to increase the monomer selectivity. Furthermore, Ni/N–C-450 shows high hydrogenolysis activity for other lignin-derived aryl ethers, such as benzyl phenyl ether, dibenzyl ether, dinaphthalene ether, benzyl 2-naphthyl ether and 3-methoxyphenol.

In this manuscript, we first report an ultrasensitive detection assay of microRNA by combing asymmetric polymerase chain reaction (A-PCR) and loop-mediated isothermal amplification (LAMP) technology. Using A-PCR obtained an extended single strand to form LAMP stem-loop structure under isothermal amplification conditions. We used miRNAs as a loop primer probe in LAMP reaction and completed its ultrasensitive and rapid detection. The established method furnished a fast, specific and efficient detection of target miRNA with a detection limit as low as 10 amol/L in 90 min.