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Potassium-selenium (K-Se) batteries have attracted more and more attention because of their high theoretical specific capacity and natural abundance of K resources. However, dissolution of polyselenides, large volume expansion during cycling and low utilization of Se remain great challenges, leading to poor rate capability and cycle life. Herein, N/O dual-doped carbon nanofibers with interconnected micro/mesopores (MMCFs) are designed as hosts to manipulate Se molecular configuration for advanced flexible K-Se batteries. The micropores play a role in confining small Se molecule (Se2–3), which could inhibit the formation of polyselenides and work as physical barrier to stabilize the cycle performance. While the mesopores can confine long-chain Se (Se4–7), promising sufficient Se loading and contributing to higher discharge voltage of the whole Se@MMCFs composite. The N/O co-doping and the 3D interpenetrating nanostructure improve electrical conductivity and keep the structure integrity after cycling. The obtained Se2–3/Se4–7@MMCFs electrode exhibits an unprecedented cycle life (395 mA h g−1 at 1 A g−1 after 2000 cycles) and high specific energy density (400 Wh kg−1, nearly twice the specific energy density of the Se2–3@MMCFs). This study offers a rational design for the realization of a high energy density and long cycle life chalcogen cathode for energy storage.

Straw incorporation is a global common practice to improve soil fertility and rice yield. However, the effect of straw incorporation on rice yield stability is still unknown, especially under high fertilization level conditions. Here, we reported the effect of straw returning on rice yield and yield stability under high fertilization levels in the rice–wheat system over nine years. The results showed that straw incorporation did not significantly affect the average rice yield of nine years. Straw incorporation reduced the coefficient of variation of rice yield by 25.8% and increased the sustainable yield index by 8.2%. The rice yield positively correlated with mean photosynthetically active radiation (PAR) of rice growth season and the effects of straw incorporation on rice yield depended on the PAR. Straw incorporation increased the rice yield by 5.4% in the low PAR years, whereas it did not affect the rice yield in the high PAR years. Long-term straw incorporation lowered soil bulk density but improved the soil organic matter, total N, available N, available P, and available K more strongly than straw removal. Our findings suggest that straw incorporation can increase rice yield stability through improving the resistance of rice plant growth to low PAR.

The analysis of cancer omics data is a "classic" problem, however, still remains challenging. Advancing from early studies that are mostly focused on a single type of cancer, some recent studies have analyzed data on multiple "related" cancer types/subtypes, examined their commonality and difference, and led to insightful findings. In this article, we consider the analysis of multiple omics datasets, with each dataset on one type/subtype of "related" cancers. A Community Fusion (CoFu) approach is developed, which conducts marker selection and model building using a novel penalization technique, informatively accommodates the network community structure of omics measurements, and automatically identifies the commonality and difference of cancer omics markers. Simulation demonstrates its superiority over direct competitors. The analysis of TCGA lung cancer and melanoma data leads to interesting findings, 33 pages, 11 figures

In cancer research, high-throughput profiling has been extensively conducted. In recent studies, the integrative analysis of data on multiple cancer patient groups/subgroups has been conducted. Such analysis has the potential to reveal the genomic commonality as well as difference across groups/subgroups. However, in the existing literature, methods with a special attention to the genomic commonality and difference are very limited. In this study, a novel estimation and marker selection method based on the sparse boosting technique is developed to address the commonality/difference problem. In terms of technical innovation, a new penalty and computation of increments are introduced. The proposed method can also effectively accommodate the grouping structure of covariates. Simulation shows that it can outperform direct competitors under a wide spectrum of settings. The analysis of two TCGA (The Cancer Genome Atlas) datasets is conducted, showing that the proposed analysis can identify markers with important biological implications and have satisfactory prediction and stability., 13 pages

The dissolved oxygen (DO) concentration is an important index of water quality. It has a significant impact on the biodegradation process in water and the survival of aquatic organisms. Low DO concentrations often exist and may result in a deterioration in water quality and an increase in wastewater treatment expenses. An analysis of the oxygen transfer efficiency as correlated with the flow characteristics of a falling jet could help to solve these problems. Experiments related to oxygen transfer along a falling water jet were conducted, and the effects of the flowrate ( Q ), falling height ( H ) and initial DO concentration ( c u ) were considered. The results demonstrated that a falling jet in air could be an effective way of improving the DO concentration. The results also indicated that the oxygen transfer efficiency is linearly dependent on c u and has a negative exponential relation with H . To deeply analyze the oxygen transfer process, the jet disturbance process was divided into 3 parts for the first time based on flow features: a smooth zone, turbulent zone and breakup zone. The results showed that the jet outlet velocity had a limited influence on the smooth zone height but assisted in jet breakup. Thereafter, a correlation modeling DO reaeration along the falling jet considering jet disturbance characteristics was obtained. This correlation was also applied to predict the aeration efficiency in experimental cases from the literature and showed good agreement with the reported results.

Melatonin mediates multiple physiological processes in plants and is involved in many reactions related to the protection of plants from abiotic stress. In this paper, the effect of melatonin on the antioxidant capacity of rice under salt stress was studied. Melatonin alleviated the inhibition of salt stress on the growth of rice seedlings, mainly by increasing the dry weight and fresh weight of shoots and roots. Melatonin alleviated the membrane damage caused by salt stress, which was mainly manifested by the decrease of TBARS content and the decrease of leaf and root damage. During the whole salt stress period, rice after melatonin pretreatment showed lower ROS (H2O2, O2•−,OH−) accumulation. In the early stage (1–3 d) of stress, the rice after melatonin pretreatment showed a strong increase in antioxidant enzyme activity, while in the later stage (5,7 d), it showed a strong increase in antioxidant content. During the whole period of salt stress, melatonin had a weak regulatory effect on AsA-GSH cycle. Through the above regulation process, the decreasing effect of melatonin on ROS content of rice under salt stress did not decrease with prolonged stress time in a short time (1-7 d). In conclusion, melatonin improved the antioxidant capacity of rice under continuous salt stress, and rice showed variable antioxidant strategies after melatonin pretreatment.

A new neolignan, (-)-(7S, 8R)-3‑methoxy-4', 7-epoxy-8, 5'-neolignane-5, 9, 3', 9′-tetraol (1) and a new biphenylpropanoid, 1, 2-epoxy-1-(3', 4'-dihydroxyphenyl-)-3-(2'', 3'', 5''-trihydroxyphenyl-) propane (2), together with eight known compounds (3-10), were isolated from the 95% EtOH extract of the leaves of Cupressus funebris Endl. Their structures were determined by spectroscopic methods including NMR, circular dichroism (CD) spectra and comparison of the NMR data with reported in references. The antioxidant activities of all compounds were evaluated by DPPH, ABTS, and FRAP methods. Compounds 2 (IC50: 33.98 ± 0.11 μM), 3 (IC50: 32.97 ± 0.63 μM), 8 (IC50: 32.07 ± 1.57 μM), and 9 (IC50: 33.30 ± 2.29 μM) showed stronger DPPH free radical scavenging activity than l -ascorbic acid (IC50: 64.31 ± 1.32 μM). Except for 4, the other compounds showed ABTS radical scavenging abilities comparable to l -ascorbic acid (54.91 ± 1.18 μM) with the IC50 ranged from 24.42 ± 1.78 μM to 138.70 ± 13.58 μM. Compound 3 (0.72 ± 0.02 mmol/g) showed the same ferric reducing antioxidant power (FRAP) as l -ascorbic acid (0.83±0.02 mmol/g).

Jia Ouyang,1 Yu Jiang,2 Chao Deng,2 Zhiyuan Zhong,2 Qing Lan1 1Department of Neurosurgery, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, People’s Republic of China; 2Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, People’s Republic of ChinaCorrespondence: Zhiyuan Zhong; Qing Lan Tel/Fax +86-512-65880098Email szlq006@163.com; zyzhong@suda.edu.cnPurpose: Glioblastoma multiforme (GBM) poorly responds to chemotherapy owing to the existence of blood-brain barriers (BBB). It has been a long desire to develop BBB-permeable vehicles to facilitate drug targeting to GBM.Method and Results: Here, we report that doxorubicin hydrochloride loaded in ApoE peptide-functionalized reduction-sensitive polymersomes (ApoE-PS-DOX) induces potent therapy of orthotopic U-87 MG model in nude mice. ApoE-PS-DOX with varying amount of ApoE (10∼ 30 mol%) all had stable DOX loading and small sizes (< 90 nm). As revealed by flow cytometry, confocal microscopy, apoptosis and MTT assays, ApoE-PS-DOX with 20 mol.% ApoE induced the best cellular uptake and inhibitory effect to U-87 MG cells, which were much better than the non-targeted PS-DOX and liposomal doxorubicin (Lipo-DOX) used in the clinic. ApoE-PS-DOX revealed a pharmacokinetic profile comparable to PS-DOX but induced considerably better growth inhibition of orthotopically xenografted U-87 MG tumors in nude mice than PS-DOX and Lipo-DOX, leading to significant survival benefits with a median survival time of 44 days, which was almost doubled relative to the phosphate-buffered saline (PBS) group. Moreover, in contrast to mice treated with Lipo-DOX and PS-DOX, ApoE-PS-DOX group exhibited little body weight loss, signifying that ApoE-PS-DOX not only has low side effects but also can effectively inhibit glioblastoma invasion.Conclusion: This ApoE-docked multifunctional polymersomal doxorubicin induces potent and safe chemotherapy of orthotopic U-87 MG model in nude mice offering an alternative treatment modality for GBM.Keywords: apolipoprotein E, polymersomes, doxorubicin, brain tumor, blood-brain barrier

Galeaspida is an endemic clade of jawless stem-gnathostomes (‘ostracoderms’), known exclusively from the Silurian and Devonian of China and Vietnam. Among galeaspids, the family Sanqiaspidae is of particular interest for providing the first information on the galeaspid trunk and caudal fin; however, the cranial morphology of sanqiaspids remains poorly known. Here we report the first occurrence of Sanqiaspis in the Xujiachong Formation of Qujing, East Yunnan, and describe new material of Sanqiaspis from two other sites in South China. The new data corroborate the presence of the two median transverse canals in Sanqiaspis as a possible synapomorphy of the Sanqiaspidae. As a key member of the Xujiachong Assemblage, Sanqiaspis is known from the Xujiachong, Guanshanpo, Posongchong, and Si Ka formations. Stratigraphic correlation of eight Early Devonian sections in South China and North Vietnam indicates that the Sanqiaspis-bearing layers can be correlated with the transitional beds between the Lianhuashan and Nahkaoling formations in Liujing, Guangxi. Therefore, the middle-upper part of the Si Ka Formation in northern Vietnam and the upper part of the Lianhuashan Formation in Guangxi should be dated as Pragian, rather than Lochkovian. The fish assemblage from the Pragian of the South China Block documents the diversification of galeaspids, notably Huananaspidiformes, and exhibits much the same endemic pattern as that of early vascular plants and brachiopods. This endemism might be linked with the semi-closed epicontinental nature of the South China Sea during the Early Devonian, which formed a biodiversity hotspot as in the modern Red Sea.

The pathological impact of haze upon the phyllosphere microbiota awaits investigation. A moderate degree of haze environment and a clean control were selected in Chengdu, China. Artemisia argyi, a ubiquitously distributed and extensively applied Chinese herb, was also chosen for experiment. Total genome DNA was extracted from leaf samples, and for metagenome sequencing, an Illumina HiSeq 2500 platform was applied. The results showed that the gene numbers of phyllosphere microbiota derived from haze leaves were lower than those of the clean control. The phyllosphere microbiota derived from both haze and clean groups shared the same top ten phyla; the abundances of Proteobacteria, Actinomycetes and Anorthococcuso of the haze group were substantially increased, while Ascomycetes and Basidiomycetes decreased. At the genus level, the abundances of Nocardia, Paracoccus, Marmoricola and Knoelia from haze leaves were markedly increased, while the yeasts were statistically decreased. KEGG retrieval demonstrated that the functional genes were most annotated to metabolism. An interesting find of this work is that the phyllosphere microbiota responsible for the synthesis of primary and secondary metabolites in A. argyi were significantly increased under a haze environment. Relatively enriched genes annotated by eggNOG belong to replication, recombination and repair, and genes classified into the glycoside hydrolase and glycosyltransferase enzymes were significantly increased. In summary, we found that both structure and function of phyllosphere microbiota are globally impacted by haze, while primary and secondary metabolites responsible for haze tolerance were considerably increased. These results suggest an adaptive strategy of plants for tolerating and confronting haze damage.

By virtue of spatiotemporal control over the chain propagating, visible-light-regulated organocatalytic photoredox cationic polymerization provides an appealing approach for the construction of metal-free, well-defined polymers and materials. However, so far, organic photocatalysts capable of mediated cationic polymerization of vinyl ethers are quite limited, and the photocontrol or efficiency is often eroded due to the difficulty in achieving a good activation-deactivation balance, which is greatly dependent on the redox property of the catalyst. Here, we introduce a new type of organic photocatalysts, bisphosphonium salts, which show high performance in the photoregulated reversible addition-fragmentation chain transfer cationic polymerization of vinyl ethers and allow the synthesis of poly(vinyl ethers) with predictable molecular weights and narrow dispersities at low ppm catalyst loadings under visible light. In particular, the tunable redox potential and excellent stability endow the bisphosphonium salts strict temporal control, thus enabling the metal-free polymerization with a halt in a long dark period.

Thin-film architectures are a staple in a wide range of technologies, such as semiconductor devices, optical coatings, magnetic recording, solar cells and batteries. Despite the industrial success of thin-film technology, mostly due to the easy fabrication and low cost, a fundamental drawback remains: it is challenging to alter the features of the film once fabricated. Here we report a methodology to modify the thickness and sequence of the innermost solid-state thin-film layers. We start with a thin-film stack of amorphous iron oxide and silver. By applying a suitable voltage bias and then reversing it, we can float the silver layer above or below the oxide layer by virtue of the migration of silver atoms. Scanning transmission electron microscopy reveals various sequences and thicknesses of the silver and oxide layers achieved with different experimental conditions. As a proof-of-principle, we show a dynamic change of structural colours of the stack derived from this process. Our results may offer opportunities to dynamically reconfigure thin-film-based functional nanodevices in situ.

Resistive random-access memory (ReRAM) is a promising candidate for the next generation non-volatile memory technology due to its simple read/write operations and high storage density. However, its crossbar array structure causes a severe interference effect known as the "sneak path." In this paper, we propose channel coding techniques that can mitigate both the sneak-path interference and the channel noise. The main challenge is that the sneak-path interference is data-dependent, and also correlated within a memory array, and hence the conventional error correction coding scheme will be inadequate. In this work, we propose an across-array coding strategy that assigns a codeword to multiple independent memory arrays, and exploit a real-time channel estimation scheme to estimate the instantaneous status of the ReRAM channel. Since the coded bits from different arrays experience independent channels, a "diversity" gain can be obtained during decoding, and when the codeword is adequately distributed over different memory arrays, the code actually performs as that over an uncorrelated channel. By performing decoding based on the scheme of treating-interference-as-noise (TIN), the ReRAM channel over different memory arrays is equivalent to a block varying channel we defined, for which we propose both the capacity bounds and a coding scheme. The proposed coding scheme consists of a serial concatenation of an optimized error correction code with a data shaper, which enables the ReRAM system to achieve a near capacity limit storage efficiency.

Inverse-sandwich structures have been observed recently for dilanthanide boride clusters, in which two Ln atoms sandwich a monocyclic Bx ring for x = 7-9. An interesting question is if larger Bx rings are possible to form such inverse-sandwich clusters. Here we address this question by investigating La2B10- and La2B11- using photoelectron spectroscopy and ab initio quantum chemical calculations. Photoelectron spectra of La2B10- and La2B11- show complicated, but well-resolved, spectral features that are used to compare with theoretical calculations. We have found that global minimum structures of the two clusters are based on the octa-boron ring. The global minimum of La2B10- consists of two chiral enantiomers with C1 symmetry, which can be viewed as adding a B2 unit off-plane to the B8 ring, whereas that of La2B11- can be viewed as adding a B3 unit in-plane to the B8 ring in a second coordination shell. Chemical bonding analyses reveal localized B-B bonds on the edge of the clusters and delocalized bonds in the expanded boron frameworks. The interactions between the La atoms and the boron frameworks include the unique (d-p)δ bonding, which was found to be the key for inverse-sandwich complexes with monocyclic boron rings. The current study confirms that the largest monocyclic boron ring to form the inverse-sandwich structures is B9 and provide insights into the structural evolutions of larger lanthanide boride clusters.

The practical application of silicon oxycarbide (SiOC) based electrodes has been restricted by poor rate performance and under capacity retention on account of sluggish electronic and ionic transport of the SiOC glass. To tackle this issue, we synthesized silicon oxycarbide-carbon hybrid nanofibers by using an economically efficient approach, which involves several steps: electrospinning the PAN nanofibers (PNFs), grafting polysiloxanes onto the PNFs and thermal conversion of the silicone/PNFs (SPNFs). The obtained 1D nanostructure endows the hybrids electrode with rapid electron transfer kinetics, robust structural stability, fast lithium ion conduction, and efficient electronic pathway. When tested as an active electrode material, the hybrids electrode delivers a reversible specific capacity of 715.8 mAh g−1 at 1C (1C = 372 mA g−1), excellent high rate performance (422.1 mAh g−1 at 20C) and outstanding capacity retention capability of 95.4% after 2000 cycles at 10C. The results well testify the potential application of silicon oxycarbide-carbon hybrid nanofibers anode for the next-generation lithium ion batteries.

The effects of spatial variability and human factors on soil lead to complex soil hydraulic properties. In areas with highly variable water levels, it is impossible to use analytic expressions to accurately quantify and describe the process of moisture transport. In this study, the HYDRUS software package was used to calculate and simulate soil moisture transport under variable water levels by analyzing soil and underground water as an integrated system, and conducting in-situ monitoring tests on a large indoor soil trough. The results showed that: (1) the initial model verification achieved by adjusting the groundwater level revealed that when the groundwater dropped, the soil moisture in the vadose zone transitioned from balanced to unbalanced to balanced again; (2) the values and development trends of the negative pressure and water content of the soil as calculated by the model using adjusted parameters were consistent with those of the measured result, which indicated that the moisture transport model established in the GSPAC system was credible; and (3) the model established by the HYDRUS software package was able to effectively predict the soil moisture transport and infiltration dynamics.

Exploiting electrocatalysis for wearable enzyme-free biosensors and biofuel cells has recently greatly developed in preliminary medical diagnosis and human healthcare fields. Herein, several facet-...

A new genus and species of the Galeaspida Qushiaspis elaia gen. et sp. nov. is described from the Lower Devonian Xujiachong Formation of Qujing, Yunnan Province, southwestern China. The new genus d...

Mixed transition-metal ions NASICON-structured compounds are enabled simultaneously as cathode and anode for aqueous Na-ion batteries (ANIBs), simplifying the fabrication process and reducing manufacturing costs in practical applications. In this study, a mixed V³⁺/Ti⁴⁺ NASICON-structured Na₂VTi(PO₄)₃@C composite acts as a bifunctional electrode material of ANIBs, delivering excellent sodium storage performance including high reversible capacity (cathode: 52.4 mAh g–¹ at 1C, anode: 59.8 mAh g–¹ at 1C, 1C = 62 mA g–¹) and remarkable rate capability (cathode: 44.8 mAh g–¹ at 20C, anode: 52.9 mAh g–¹ at 20C), as well as long cycle life. Meanwhile, ex situ X-ray photoelectron spectra (XPS) measurements reveal that V⁴⁺/V³⁺ and Ti⁴⁺/Ti³⁺ oxidation/reduction couples are redox-active sites of NVTP@C cathode and anode, respectively. When NVTP@C assembled into symmetric ANIBs, a full cell achieves ultrahigh stability of over 2500 cycles at 10C, showing broad prospects in large-scale electric energy storage applications.

Let G and H be finite undirected graphs. The Ramsey number R(G, H) is the smallest integer n such that for every graph F of order n, either F contains a subgraph isomorphic to G or its complement $${\overline{F}}$$ contains a subgraph isomorphic to H. An (s, t)-graph is a graph that contains neither a clique of order s nor an independent set of order t. In this paper we obtain some inequalities involving Ramsey numbers of the form $$R(K_4-e,K_t)$$ . In particular, a constructive proof implies that if G is a $$(k,s+1)$$ -graph, H is a $$(k,t+1)$$ -graph, and both G and H contain a $$(K_k-e)$$ -free graph M as an induced subgraph, then we have $$R(K_{k+1}-e,K_ {s+t+1}) > |V(G)| + |V(H)| + |V(M)|.$$ Furthermore, if $$s \le t$$ , then $$R(K_4-e,K_ {s+t+1}) \ge R(3,s+1)+R(3,t+1)+s$$ . In the experimental part, we use the $$(K_4-e)$$ -free graph generation process to construct graphs witnessing lower bounds for $$R(K_4-e,K_t)$$ , and compare the results obtained by this approach to the results obtained by analogous triangle-free process. Finally, some open problems involving Ramsey numbers of the form $$R(K_4-e,K_t)$$ and their asymptotics are posed.

In the development of fuel cells, it is the key to large-scale commercialization of fuel cells to rationally design and synthesize efficient and non-noble metals-based bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this paper, spinel CoFe2O4/carbon nanotube composites (CoFe2O4/CNTs/FA) were synthesized by solvothermal and calcination method. XRD, TEM, XPS and BET characterizations indicate that the addition of complexing agent fumaric acid can improve the crystal growth kinetics and morphology of CoFe2O4/CNTs nanohybirds. The as-synthesized CoFe2O4/CNTs/FA pyrolyzed at 500 °C have an outstanding bifunctional catalytic activity for ORR and OER with the potential of 1.62V (vs. RHE) at a current density of 10 mA/cm2 and half-wave potential E1/2 = 0.808V (vs. RHE) in alkaline electrolyte, respectively. It is obviously better than unloaded CoFe2O4 nanoparticles and commercial CNTs. CoFe2O4/CNTs/FA also exhibit better methanol tolerance ability and durability than commercial Pt/C and RuO2 catalyst. This investigation broadens an idea of simple compounding of spinel with carbon-based materials to improve electrochemical properties.

To clarify the function of the nitrogen-containing structures on the adsorption of heavy metals, nitrogen-enriched biochars (NBCs) mainly composed of pyrrolic, pyridinic, and graphitic nitrogen were prepared to investigate the interaction mechanism with Cd(II). The results of batch experiments revealed that the saturated Cd(II) adsorption capacities of Pr-NBC, Pd-NBC, and Gp-NBC were 12.68, 24.04, and 35.95 mg g−1 respectively. The strongest adsorption ability was found for the Gp-NBC and was ascribed to the enhancement of graphitic nitrogen. The results from SEM-EDS and XRD, and the zeta potentials for the materials revealed that carbonate precipitation, cation exchange, and electrostatic interactions contributed to the adsorption of Cd(II). XPS and FTIR demonstrated that nitrogen in the carbon framework might have promoted the adsorption by forming cation–π interactions between graphitic nitrogen and Cd(II). The electrostatic potential distribution of the nitrogen with different configurations fully confirmed this. The theoretical calculations also proved that graphitic nitrogen had the lowest interaction energy to Cd(II), which further verified the strong contribution of graphitic nitrogen to the adsorption of heavy metal. Nitrogen-enriched biochar effectively adsorbs, changes the migration process of heavy metals in the natural environment, and thus alleviates the current situation of heavy metal pollution.

Carbon fiber reinforced polymer (CFRP) is an anisotropic material with outstanding tensile strength in the axial direction but low compressive strength in the radial direction. In the process of line construction, such as wire crimping and conductor clamping, radial pressure failure and slip failure easily occur. This paper applies finite element analysis (FEA) to the parameters influencing the radial stress and displacement in a CFRP core to research the failure modes of the CFRP core. The selected parameters are the interference of the CFRP core, the friction coefficient between the core and inner wedge, and the angle of the inner wedge. The finite element method is applied to analyze a CFRP core with a self-tightening clamp to find the optimum condition parameters so that the CFRP core experiences neither slip failure nor radial pressure failure. From the study, lower interference and larger friction coefficient and angle lead to lower radial stress. The interference has the largest effect on the mitigation of radial pressure failure. For larger interference, a larger friction coefficient and angle mitigate slip failure. According to the analytic results, an interference between 0.02 mm and 0.025 mm and an angle larger than 3°, coupled with a friction coefficient larger than 0.3, best stop slip failure and radial pressure failure.

Organocatalytic atom transfer radical polymerization (O-ATRP) is recently emerging as an appealing method for the synthesis of metal-free polymer materials with well-defined microstructures and architectures. However, the development of highly effective catalysts that can be employed at a practical low loading are still a challenging task. Herein, we introduce a catalyst design logic based on heteroatom-doping of polycyclic arenes, which leads to the discovery of oxygen-doped anthanthrene (ODA) as highly effective organic photoredox catalysts for O-ATRP. In comparison with known organocatalysts, ODAs feature strong visible-light absorption together with high molar extinction coefficient (ε455nm up to 23,950 M–1 cm–1), which allow for the establishment of a controlled polymerization under sunlight at low ppm levels of catalyst loading., Organocatalytic atom transfer radical polymerization (O-ATRP) is attractive due to its metal-free nature but catalysts are rarely applied at a low loading. Here the authors introduce a catalyst design logic based on heteroatom-doping of polycyclic arenes, which led to the discovery of oxygen-doped anthanthrene as an organic photoredox catalysts for O-ATRP.

This work represents the first [4+2] annulation of hydroxamic acids with olefins for the synthesis of benzo[c][1,2]oxazines scaffold via anode-selective electrochemical oxidation. This protocol features mild conditions, is oxidant free, shows high regioselectivity and stereoselectivity, broad substrate scope of both alkenes and hydroxamic acids, and is compatible with terpenes, peptides, and steroids. Significantly, the dioxygenation of olefins employing hydroxamic acid is also successfully achieved by switching the anode material under the same reaction conditions. The study not only reveals a new reactivity of hydroxamic acids and its first application in electrosynthesis but also provides a successful example of anode material-tuned product selectivity.

Photoreforming of lignocellulose for sustainable H2 generation appears to be a good option at the time that biomass wastes are being degraded. Recently, polymeric carbon nitride (PCN) has emerged as a promising alternative for the photorefoming reaction, however, its photocatalytic performance is largely limited by its severe recombination of charge carriers. Here, we developed an approach, for the first time, to construct a curly-like carbon nitride nanosheets with the formation of in-plane surface dyadic heterostructure for steering the charge transfer and optimizing the electronic band structure. This PCN material shows superior photoreforming H2 evolved activity of 122.77 μmolh−1 (i.e. 4092 μmolh−1g−1) from the aqueous lignocellulose solution (using Pt as cocatalyst), 15.6 folds of pristine PCN under visible light irradiation, together with an apparent quantum efficiency (AQE) of 7.87% (λ = 420 nm). It enables the visible-light-driven conversion of several kinds of lignocellulose including the monosaccharides, disaccharides, hemicellulose, and cellulose. Additionally, when used as a photocatalyst for water splitting, it achieves a remarkable H2 production rate of 22043 μmolh−1g−1 (∼56.0 folds’ increases than pristine PCN) with a superior high AQE of 41.2%, as well as a high CO reduction rate of 56.3 μmolh−1 from the photocatalytic CO2 conversion, 24.5 times than pristine PCN.

In the design of multifunctional orthopedic biomaterials, enhanced biological activities, reinforced mechanical property, improved hydrophilicity and osteo-compatibility are the essential criteria. For achieving these goals, here a bioactive multifunctional Ti6Al4V implant with nanowire structured surface topography is designed and fabricated using 3D printing technique. Selective laser melting (SLM) is applied to fabricate scaffold materials with diamond cellular structures to meet the requirements of load-bearing function of bone tissue. With the alkali treatment of sodium hydroxide, osteogenic layer of Na2Ti6O13 is generated on the porous Ti6Al4V, on which apatite is easily deposited and immobilized. Clusters of Na2Ti6O13 exhibits excellent hydrophilicity and surface roughness with precise control of alkali treatment time. Additionally, the compressive strength of the modified porous Ti6Al4V (121.2 MPa-84.5 MPa) decreases due to the corrosion of sodium hydroxide, while it can satisfy the basic mechanical requirement of cortical bone. The results prove that the surface-modified 3D printed porous Ti6Al4V possesses balanced mechanical strength and osteogenic function, promising for potential application in complex multifunctional bone defects.

SiC/SiO2 nanochains were synthesized on a carbon fiber substrate by a catalyst-free thermal evaporation method in the Ar/CO atmosphere. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the as-synthesized SiC/SiO2 nanochains are composed of single-crystalline SiC nanowires and amorphous SiO2 beads. The introduction of CO can promote the formation of SiO2, so that the SiC/SiO2 nanochains are subsequently formed during cooling. In addition, the photoluminescence spectrum of SiC/SiO2 nanochains showed a broad emission peak at around 350 nm, which is ascribed to the oxygen discrepancy in the SiO2 beads as well as the SiC/SiO2 interfacial effect. These findings can provide guidance for further study of the vapor growth of 1D SiC-based materials.

This paper presents a simple strategy to adjust bacterial cellulose (BC) nanofiber distribution on the biomimetic 3D scaffolds by in situ bacteria culture on the protein scaffolds which were prepared by selecting gelatin (Gel) with positive charge and silk fibroin (SF) with negative charge. The protein scaffolds with different structures and properties were obtained by adjusting the proportion of Gel and SF. Due to the electrical attraction and repulsion of bacteria and protein, the density and distribution of bacteria on the protein scaffolds is obviously different. Thus, after in situ culture, protein/BC scaffolds with different nanofibers density and distribution from basically adhering to the pore wall to distributing in the middle pore were obtained, which make different cell shape and distribution. It is can be easily realized by adjusting the properties of scaffold materials to guide the growth of bacteria which provides a simple idea for the design of tissue engineering scaffolds applied in medical implants, cell supports and other tissue regeneration.

Emerging sodium-ion batteries (SIBs) have aroused great attention in large-scale energy storage. However, it is still a great challenge to develop suitable electrode materials due to the large radi...

The wearable and integrated sensing platform is a promising choice for developing real-time analytic electronics with clear advantages but still poses challenges, such as the realization of high precision, low limit of detection (LOD), moderate mechanical capacity, integration, and miniaturization. In this work, a simple printed wearable smartsensor has been fabricated with the aid of electrochemical plating methods with bismuth (Bi) films. The excellent sensing behaviors, including linear relationship, selectivity, stability, repeatability, and the LOD at ppb levels, have been obtained by this smartsensor. Additionally, the highly flexible textile-based sensor exhibits potential application on the substrates of daily cloth, sports T-shirt, and sports wristbands, and it maintains good stability under repeated deformations of washing and twisting. Importantly, integrated with printed circuit board, single chip micyoco, and Bluetooth modules, a smartsensing platform is successfully acquired for real-time detection of heavy metals (e.g., Zn, Cd, Pb, etc.). Finally, actual samples of human sweat, seawater, cosmetics, and drinking water have been remotely successfully demonstrated for detection by this smartsensor, enabling a great promise for fast on-site screening of samples in practical application.

This paper mainly studies to explore a three-dimensional geometric model including three modules of a sandcastle foundation with optimal stability. Firstly, based on the knowledge of streamline structure, structural mechanics, and fluid mechanics, the most stable sand pile foundation model under the action of tidal current and wave is established. Secondly, by limiting the degree of allowable aggregation, the discrete global optimization algorithm based on the continuous descent method is adopted to find out the optimal water-sand ratio. Finally, we apply the above results to verify the reliability of the optimal model by comprehensively considering the influence of rainfall factors on sandcastles.

[Image: see text] Selective inhibition of Janus kinases (JAKs) is an arising strategy in drug discovery. Covalent inhibitors targeting a unique cysteine in JAK3 exhibit ultraselectivity among JAK family members. However, safety and tissue specific concerns still remain. A prodrug of a known JAK3 covalent inhibitor sensitive to H(2)O(2) was designed and synthesized and its therapeutic effect was evaluated in the CIA (collagen-induced arthritis) mice model of RA (rheumatoid arthritis). The prodrug strategy relied on the introduction of a hydrogen peroxide-sensitive borate trigger group to avoid random covalent binding to thiol functionalities in biomacromolecules. The results show that the prodrug can be activated and released under pathophysiological concentration of H(2)O(2). In addition, the prodrug demonstrated stability to the physiological environment. In comparison to the parent compound, the prodrug showed a similar therapeutic effect in the CIA model but notably exhibited lower toxicity and a larger therapeutic window.

LaFeO3nanoparticles-modified RuO2and RuO2samples were fabricated by a thermal decomposition and was characterized by powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and cyclic voltammetry tests. XRD results reveal that the RuO2and RuO2-LaFeO3samples are mainly a rutile structure. Compared with the RuO2sample, the RuO2-LaFeO3sample has smaller crystalline grain size. Cyclic voltammetry analysis shows the voltammetric behaviour and the characteristic potentials of the RuO2and the RuO2-LaFeO3samples are similar in 1.0 M KOH solution. Voltammetric charge analysis reveals that the RuO2-LaFeO3sample has higher concentrated of surface active species and larger exposed surface area than the RuO2sample. Capacitive measurement results show the Double-layer capacitance (Cdl) and the electrochemical surface area (ECSA) values of the RuO2-LaFeO3sample are approximately 2 times larger than those of the RuO2sample, indicating that the electrochemical active surface area increase when integrating of RuO2with LaFeO3nanoparticles.

Stable fuel distribution and mixing is noteworthy for increasing the efficiency of the scramjet engine at high-speed flight. In this work, numerical studies are accomplished to inspect and disclose the effects of cavity back height on the fuel (hydrogen) spreading inside the cavity flameholder at supersonic flow. The effects of both positive and negative back height on fuel distribution are explained by analysis of the three-dimensional jet contour. The implications of multi-jets directions on the hydrogen distribution are also presented in this research. RANS equations with the SST turbulence model are employed for the computational investigations of 3-D supersonic air and fuel inside the cavity. Our outcomes show that the injection of the opposing multi-jets is more effective on fuel mixing when the back height is positive. However, multi hydrogen co-jet distributes the fuel jets homogenous inside the cavity for negative cavity back height. According to our results, the weakening the main circulation improves the mixing performance inside the cavity.

Fairness is an important criterion for achieving sustainable urban development. While most existing studies focus on accessing or evaluating the fairness condition of a given transit network, this study explicitly incorporates fairness as an objective in the planning step. A multi-objective bilevel programming model is developed where the lower level problem is the reliability-based transit assignment problem and the upper level problem is to determine optimal frequency settings to simultaneously minimise the total effective travel cost and maximise the network fairness condition. A multi-objective Artificial Bee Colony algorithm is developed to solve the bilevel model. Numerical studies find that: (1) increasing the frequency may not improve the fairness condition; (2) there is a tradeoff between the two objectives (3) the effect of passengers’ risk aversion attitude on the fairness measurement depends on the frequency setting; it could either amplify the fairness measurements or have no impact.

Heterogeneity is a hallmark of many complex diseases. There are multiple ways of defining heterogeneity, among which the heterogeneity in genetic regulations, for example GEs (gene expressions) by CNVs (copy number variations) and methylation, has been suggested but little investigated. Heterogeneity in genetic regulations can be linked with disease severity, progression, and other traits and is biologically important. However, the analysis can be very challenging with the high dimensionality of both sides of regulation as well as sparse and weak signals. In this article, we consider the scenario where subjects form unknown subgroups, and each subgroup has unique genetic regulation relationships. Further, such heterogeneity is "guided" by a known biomarker. We develop an MSF (Multivariate Sparse Fusion) approach, which innovatively applies the penalized fusion technique to simultaneously determine the number and structure of subgroups and regulation relationships within each subgroup. An effective computational algorithm is developed, and extensive simulations are conducted. The analysis of heterogeneity in the GE-CNV regulations in melanoma and GE-methylation regulations in stomach cancer using the TCGA data leads to interesting findings., Comment: 24 pages, 8 figures

In the present paper, we devote our effort to a nonlinear inverse problem for recovering a time-dependent potential term in a multi-term time fractional diffusion equation from an additional measurement in the form of an integral over the space domain. First we study the existence, uniqueness, regularity and stability of the solution for the direct problem by using the fixed point theorem. And we obtain the uniqueness of the inverse time-dependent potential term problem. Numerically, we use the Levenberg–Marquardt method to find the approximate potential function. Four different examples are presented to show the feasibility and efficiency of the proposed method.

The Keap1 (Kelch-like ECH-associated protein 1)-Nrf2 (nuclear factor erythroid 2-related factor 2)-ARE (antioxidant response element) pathway is the major defending mechanism against oxidative stresses, and directly disrupting the Keap1-Nrf2 protein-protein interaction (PPI) has been an attractive strategy to target oxidative stress-related diseases, including cardiovascular diseases. Here, we describe the design, synthesis, and structure-activity relationships (SARs) of indoline-based compounds as potent Keap1-Nrf2 PPI inhibitors. Comprehensive SAR analysis and thermodynamics-guided optimization identified 19a as the most potent inhibitor in this series, with an IC50 of 22 nM in a competitive fluorescence polarization assay. Further evaluation indicated the proper drug-like properties of 19a. Compound 19a dose-dependently upregulated genes and protein level of Nrf2 as well as its downstream markers and showed protective effects against lipopolysaccharide-induced injury in both H9c2 cardiac cells and mouse models. Collectively, we reported here a novel indoline-based Keap1-Nrf2 PPI inhibitor as a potential cardioprotective agent.

In this paper, we consider a problem of recovering a space-dependent source for a time fractional diffusion wave equation by the fractional Landweber method. The inverse problem has been transforme...

Baicalensines A (1) and B (2) were isolated from the roots of Thalictrum baicalense and structurally characterized using spectroscopic data, 13C NMR calculations, and the CASE algorithm. Compound 1, representing a new class of alkaloid dimers, contains berberine conjugated to a ring-opened isoquinoline. Compound 2 is the first reported natural benzylisoquinoline bearing a formyl group at C-3. Plausible biosynthetic pathways are proposed. Compound 1 exerted moderate cytotoxicity against the Caco-2 and HL-60 cell lines.

Nano-sized transition-metal carbides with high purities were synthesized by vacuum carbothermal reduction coupled with a novel method for the removal of free carbon by molten calcium treatment. Transition-metals oxides were firstly reduced by excessive carbon black under vacuum condition, and then the obtained product was treated in molten calcium to remove the free carbon. After acidic leaching the product, pure carbides were obtained. The excess carbon in the carbothermic reduction stage could not only increase the contact between reactants and make the reduction more thorough, but also act as barrier to restrict the grain growth of the products. The effects of carbothermic reduction temperature, calcium treatment temperature and particle sizes of oxides on the reaction products were discussed in detail. It was concluded that after carbothermic reduction of corresponding oxides at 1823 K in vacuum and the following calcium treatment at 1173 K, TiC, ZrC, HfC, V8C7, NbC and TaC with the particle sizes of 100 nm, 70 nm, 130 nm, 200 nm, 150 nm and 120 nm, could be prepared, respectively.

The fuel mixing process within the combustion chamber is a critical procedure for advance of scramjet engine. In current study, the influence of free stream angle on the fuel mixing process of multi jets was thoroughly investigated. This research attempts to applied computational technique to disclose the structure of multi-fuel jets when the supersonic air stream is not normal to the jet direction. The effect of both positive and negative supersonic free stream on the diffusion and penetration of multi-hydrogen jets is fully described. The attention of this research is the flow structure of the multi jets and their interaction in the presence of different free stream angle. Our results indicate that the positive free stream angle expands the mixing zone in the downstream while the negative angle of free stream limited jet distribution inside the combustor. Our results show that mixing efficiency increase approximately 50% when the angle of free stream augments from +20° to −20°. According to our findings, mixing efficiency surges up to 17% when the jet spaces are increased from 4Dj to 10 Dj.

The efficient fuel mixing in the combustion tank enhances the overall performance of scramjet. Current attempt examines the existence of the strut on the fuel mixing of the multi hydrogen jets at supersonic flow. The numerical approach was employed to visualize the 3D flow behind the strut with multi fuel-jets. The free-stream Mach is 2.2, and four multi jets released hydrogen inside the combustor with the sonic condition. The impact of jet arrangements and the total pressure ratio on the mixing effect of the strut is fully described. Our results indicate that fuel mixing and penetration improved due to the formation of the large subsonic region behind the strut. According to achieved results, the increasing jet space from 1Dj to 5Dj raises the overall mixing to 15% in our proposed model.

As the ocean data acquired by the Argo project is increasingly huge, how to use artificial intelligence to analyze it so as to discover the distribution and variation of ocean temperature with space and time becomes an important research topic in the world. In this article, a spatio-temporal dependence-based tensor fusion method is proposed, which can be used to determine and analyze the thermocline. In the time dimension, long short-term memory is used to predict the temperature of seawater; in the spatial dimension, the thermocline is found incrementally by using tensor analysis. Experiments on BOA Argo data from 2004 to 2016 show that the proposed method can accurately determine the boundary of the thermocline and predict the future trend of the thermocline.

l-Proline is an important amino acid that has various industrial applications. Industrial l-proline-producing strains are obtained by the mutagenesis of Corynebacterium glutamicum. In this study, the optimized C. glutamicum genome-editing tools were further applied in the de novo construction of a hyper-l-proline-producing strain. Overexpression of a feedback inhibition-resistant γ-glutamic kinase mutant ProBG149K, deletion of a proline dehydrogenase to block l-proline degradation, overexpression of glutamate dehydrogenase to increase glutamate synthesis flux, the mutation of 6-phosphate gluconate dehydrogenase and glucose-6-phosphate-dehydrogenase in the pentose phosphate pathway to enhance NADPH supply, the deletion of pyruvate aminotransferase to decrease the byproduct l-alanine synthesis, and weakening of α-ketoglutarate dehydrogenase to regulate the TCA cycle were combined to obtain ZQJY-9. ZQJY-9 produced 19.68 ± 0.22 g/L of l-proline in flask fermentation and was also demonstrated at the 3 L bioreactor level by fed-batch fermentation producing 120.18 g/L of l-proline at 76 h with the highest productivity of 1.581 g/L/h.

The production of acetone-butanol-ethanol by solventogenic Clostridium using lignocellulosic biomass can be a potential alternative to petroleum-based butanol. However, previous studies on nondetoxified lignocellulose hydrolysate could not provide better results when compared to those in synthetic medium. In this study, we engineered the pentose pathway of Clostridium beijerinckii NCIMB 8052, which was then subjected to adaptive laboratory evolution in the gradient mixture of synthetic medium and pretreated corn stover enzymatic hydrolysate (CSH) prepared according to the National Renewable Energy Laboratory (NREL) standard. The final resultant strain CIBTS1274A produced 20.7 g/L of total solvents in NREL CSH diluted to 6% initial total sugars, supplemented with ammonium acetate. This performance was comparable with that of corn-based butanol. In addition, this strain was successfully used in the scale-up operation using nondetoxified corn stover and corncob hydrolysate at Lignicell Refining Biotechnologies Ltd., which once was the only commercial biobutanol industry in the world.

A MoC/C composite material was conveniently synthesized via self-polymerization and pyrolysis. MoC nanoparticles are evenly distributed upon the carbon matrix and feature a cross-linked structure that can efficiently restrain the aggregation of MoC nanoparticles and relieve the volume alteration during the charging/discharging process. Moreover, the carbon material highly improved conductivity and reduced charge transfer resistance of the MoC/C-based electrode; this ensured its long-term stability with superior reversible capacity. At a current density of 1 A g−1, the MoC/C electrode delivered a reversible specific capacity of 550 mAh g−1 even after 500 cycles, demonstrating excellent electrochemical performance. This MoC-based electrode with an ultralong life cycle could be utilized as an anode material for next-generation lithium-ion batteries.

For solving a class of complex symmetric system of linear equations, we apply the minimum residual technique to the modified Hermitian and skew-Hermitian splitting (MHSS) iteration scheme and propose an iteration method referred to as minimum residual MHSS (MRMHSS) iteration method. Compared with the classical MHSS method, the MRMHSS method has two more iteration parameters, which can be automatically and easily computed. Then, some properties of the MRMHSS iteration method are carefully studied. Finally, we use four examples to test the performance of the MRMHSS iteration method by comparing its numerical results with three other iteration methods.

Based on the experimental data available in the literature, the Ag-X (X = B, Fe, Sm, Pu) binary systems were assessed by means of the CALPHAD (CALculation of PHAse Diagrams) approach. Six intermetallic compounds, i.e. αAg2Sm, βAg2Sm, AgSm, Ag51Sm14, Ag51Pu14 and Ag2Pu, were treated as stoichiometric phases. The solution phases including liquid, (Ag, γFe, δPu), (βB), (αFe, δFe, ePu), (αSm, γSm), (βSm), (αPu), (βPu), (γPu) and (δ’Pu) were described by the substitutional solution model with the Redlich–Kister polynomial. A set of self-consistent thermodynamic parameters for each of the binary systems was obtained. The calculated phase diagrams and thermodynamic properties were in agreement with the reported experimental data.