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2D moiré superlattices offer a versatile platform for manipulating quantum materials, exploiting their spatially varying atomic registry to modify electronic structures, resulting in the emergence of flat electronic minibands, enhanced electronic interactions, and the onset of novel quantum phenomena. Despite extensive investigations into moiré excitons within twisted bilayer moiré superlattices, the interplay between moiré superlattices and optical microcavities remains elusive. Here, a WSe2 homobilayer with a small twist angle positioned on optical microcavities atop a SiO2 (285 nm)/Si substrate is investigated. Utilizing low‐temperature photoluminescence (PL) spectroscopy, it is observed that the twisted homobilayer at the edge of the optical cavity (Edge‐THB) exhibits enhanced localization of moiré excitons and a deeper moiré potential. This behavior is attributed to the combined influence of strain induced by the optical microcavity structure on the moiré superlattice and the amplification of the electromagnetic field. Furthermore, the existence of moiré excitons through a comprehensive analysis, encompassing temperature‐dependent PL spectra, circularly polarized PL spectra, and Landé g‐factor measurements for Edge‐THB is validated. These findings provide valuable insights into the intricate interaction between moiré superlattices and optical microcavities, paving the way for future applications in quantum technologies. [ABSTRACT FROM AUTHOR]

Under the repeated action of aircraft taxiing load, the subgrade plastic deformation becomes the key factor affecting the service performance of the airfields when salinized silt is used to fill the subgrade. In this study, the dynamic triaxial tests were carried out on a region in the northern part of China to study the effects of different salt contents on the dynamic characteristics of silt under cyclic loading. A prediction model for the salinized silt dynamic strength with a plastic strain of 4% as the failure criterion for the subgrade was thus proposed. It is found that with the increase of dynamic stress amplitude, the salinized silt plastic deformation transforms gradually from plastic deformation to incremental failure. The salt contents significantly influence the plastic strain and critical dynamic stress of silt. The strength of the salinized silt specimen is related to the ion concentration in the soil pores and the arrangement pattern of soil particles, as indicated by the progressive strength increase of the salinized silt at the low salt content of 1% and a further gradual decrease at high salt content. [ABSTRACT FROM AUTHOR]

Let A and B be two families of sets. A is t -intersecting if | A 1 ∩ A 2 | ≥ t for all A 1 , A 2 ∈ A. A and B are cross-intersecting if A ∩ B ≠ 0̸ for all A ∈ A and B ∈ B. Let n , k , t ≥ 1 be non-negative integers with n ≥ 2 k + t − 1. Let A ⊆ [ n ] k + t − 1 and B ⊆ [ n ] k . Frankl proved that if A is t -intersecting and | A | ≥ 1 , then | A | + | B | ≤ n k − n − k − t + 1 k + 1. In this paper, we sharpen Frankl's inequality when | A | ≥ 2 , that is, if A is t -intersecting and | A | ≥ 2 , then | A | + | B | ≤ n k − n − k − t + 1 k − n − k − t k − 1 + 2 for k ≥ 3. Furthermore, we also characterize all extremal families achieving the extremal bounds. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a D-type highly sensitive surface plasmon resonance (SPR)sensor based on multilayer films coated with photonic crystal fiber (PCF). Silver was selected as the plasmon material because its SPR spectrum is sharper than gold. Meanwhile, we used the titania (TiO2) as the second layer film since it could prevent the oxidation of silver and enhance the SPR effect. We simulated the refractive index sensing performances using the finite element method (FEM). This paper optimized the air hole size, polishing depth, silver film thickness, and TiO2 thickness. The multilayer film structure showed a significant improvement in the wavelength sensitivity of the sensor. The result showed that the maximum sensitivity reached 11,000 nm/RIU, which was increased by 139% compared with a single silver film. The sensor was suitable for accurately detecting the medical treatment and organic chemicals because of its high sensitivity and FOM. [ABSTRACT FROM AUTHOR]

Background: Ovarian development is an important prerequisite and basis for animal reproduction. In many vertebrates, it is regulated by multiple genes and influenced by sex steroid hormones and environmental factors. However, relative information is limited in shellfish. To explore the biological functions and molecular mechanisms of mRNA and non-coding RNA that regulate ovarian development in Scapharca broughtonii, we performed whole transcriptome sequencing analysis on ovaries at three developmental stages. Furthermore, the biological processes involved in the differential expression of mRNA and ncRNA were analyzed. Results: A total of 11,342 mRNAs, 6897 lncRNAs, 135 circRNAs, and 275 miRNAs were differentially expressed. By mapping the differentially expressed RNAs from the three developmental stages of Venn diagram, multiple groups of shared mRNAs and lncRNAs were found to be associated with ovarian development, with some mRNA and ncRNA functions associated with steroid hormone. In addition, we constructed and visualized the lncRNA/circRNA-miRNA-mRNA network based on ceRNA targeting relationships. Conclusions: These findings may facilitate our further understanding the mRNA and ncRNAs roles in the regulation of shellfish reproduction. [ABSTRACT FROM AUTHOR]

Pore structures are critical for most properties of cementitious materials. To describe the initial pore structure of fresh cement paste, which is the foundation of the evolution of a pore network induced by hydration of cement particles in hardened concrete, statistical modelling of pore structure is carried out based on a concentric-shell sphere model, by taking cement paste as a random two-phase media. Calculations by the dispersion models agree well with the pore size distributions tested by the low-field H1 nuclear magnetic resonance (NMR) technique. For cement paste that disperses completely with the help of a dispersant, a hard sphere model is practical. However, in most real conditions, an agglomeration of cement particles will occur both before and after mixing with water, which can be characterized by the redistribution of pore size determined by the critical grain size and the hardness parameter in the concentric-shell model, respectively. Calculation results suggest that agglomeration of particles leads to coarser pores. This work will promote the understanding of the formation mechanisms of pore networks and further offers a foundation for modelling the evolution of pore structures in cementitious materials. [ABSTRACT FROM AUTHOR]

Ultrasonic nondestructive testing (NDT) provides a valuable insight into the integrity of stainless steel structures, but the noise caused by the scattering of stainless steel microstructure often limits the effectiveness of inspection. This work presents a novel adaptive filtering approach to enhance the signal-to-noise ratio (SNR) of a measured ultrasonic signal from the inspection of a stainless steel component, enabling the detection of hidden flaws under strong noise. After the spectral modeling of the noisy ultrasonic NDT signal, the difference between the spectral characteristics of a flaw echo and that of grain noise is highlighted, and a reference spectrum model to estimate the frequency spectrum of the echo reflected by any possible flaw is developed. Then, the signal is segmented and the similarity between the spectra of data segments and the reference spectra is evaluated quantitatively by the spectral similarity index (SSI). Based on this index, an adaptive time-frequency filtering scheme is proposed. Each data segment is processed by the filtering to suppress the energy of noise. The processed data segments are recombined to generate the de-noised signal after multiplying weighting coefficients, which again is determined by the SSI. The performance of the proposed method for SNR enhancement is evaluated by both the simulated and experimental signal and the effectiveness has been successfully demonstrated. [ABSTRACT FROM AUTHOR]

The adsorption and condensation of water molecules in the pores of cementitious materials play a crucial role in the mechanical performance and durability of concrete. The Kelvin equation is generally employed to describe the water condensation in porous materials. However, it requires modification for condensation behavior in nano and micro scales of pores. In the present work, various widths of slit models for several cementitious minerals were established. The adsorption isotherms in slit pores were calculated using the hybrid of Grand Canonical Monte Carlo and Molecular Dynamics simulations, obtaining the relationship between the critical pressures for condensation and pore sizes. Then, a modified Kelvin equation was proposed, with discussion on a new reasonable method for determining the real thickness of adsorbed water film. The results demonstrate that condensation will occur in the slits within the critical width range, which promotes the surface adsorption to achieve complete adsorption. Therefore, the location of the interface between the adsorbed water film and condensed water bulk is fixed in the same mineral during condensation. The modified Kelvin equation shows higher accuracy than traditional Kelvin equations at the nano and micro scale. This work promotes a deeper understanding of the interaction mechanism of water with cementitious minerals and inspires more fundamental realization in the design of concrete durability. • Water adsorption and condensation in CSH slits are calculated by GCMC simulations. • Water condenstion induced complete adsorption was firstly found. • The interface location between adsorbed layer and condensed bulk is determined. • The Kelvin equation is refined to describe condensation in micropores of CSH. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell structured NPs that consisted of Pt cores and Sn shells were prepared. • The partial coverage of Pt by Sn facilitated their adsorption of C O bonds. • The strong Pt-Sn interaction is responsible for the enhanced performance. The selective hydrogenation of cinnamaldehyde (CAL) to prepare cinnamyl alcohol (COL) is challenging as the unwanted hydrogenation of C C bond in CAL is thermodynamically more favorable than the hydrogenation of C O bond. We herein designed core–shell structured nanoparticles (NPs) that consisted of Pt cores and Sn shells to catalyze the CAL to COL conversion. By simply changing the amount of Sn precursor, we generated Pt@Sn NPs with different Sn shell thickness and catalytic performance. Among the samples, Pt@Sn/SiO 2 with Pt/Sn of 1/1 achieved the highest CAL conversion (87.2 %) as well as the COL selectivity (95.4 %), which were 5-fold and 6-fold, respectively, higher than those of Pt/SiO 2. This catalyst was also applicable to the hydrogenation of other α, β-unsaturated aldehyde and unsaturated carbonyl compounds. Both experiments and theoretical calculations indicated that the strong Pt-Sn interaction and the partial coverage of Pt by Sn facilitated their adsorption of C O bonds, thus enhancing the conversion of CAL and the selectivity towards COL. [ABSTRACT FROM AUTHOR]

Lots of symmetric properties are well-explored and analyzed in extremal graph theory, such as the well-known symmetrization operation in the Turán problem and the high symmetric in the extremal graphs. This paper is devoted to studying the Lagrangian of hypergraphs, which connects to a very symmetric function—the Lagrangian function. Given an r-uniform hypergraph F, the Lagrangian density π λ (F) is the limit supremum of r ! λ (G) over all F-free G, where λ (G) is the Lagrangian of G. An r-uniform hypergraph F is called λ -perfect if π λ (F) equals r ! λ (K v (F) − 1 r) . Yan and Peng conjectured that: for integer r ≥ 3 , there exists n 0 (r) such that if G and H are two λ -perfect r-graphs with | V (G) | and | V (H) | no less than n 0 (r) , then the disjoint union of G and H is λ -perfect. Let S t denote a 3-uniform hypergraph with t edges { e 1 , ⋯ , e t } satisfying that e i ∩ e j = { v } for all 1 ≤ i < j ≤ t . In this paper, we show that the conjecture holds for G = S 2 and H = S t for all t ≥ 62 . Moreover, our result yields a class of Turán densities of 3-uniform hypergraphs. In our proof, we use some new techniques to study Lagrangian density problems; using a result of Sidorenko to find subgraphs, and a result of Talbot to upper bound the Lagrangian of a hypergraph. [ABSTRACT FROM AUTHOR]

Obtaining Turán densities of hypergraph through determining Lagrangian densities have been studied actively. Sidorenko showed that the Lagrangian density of an r-uniform hypergraph equals the Turán density of the extension of this hypergraph. Indeed, Lagrangian density and Turán density are the same for a large class of hypergraphs such as hypergraphs covering pairs. Let Pr,s be the r-uniform hypergraph with two edges intersecting at s vertices. Sidorenko determined the Lagrangian densities of Pr,s for r = 3 and s = 1 or 2, or r = 4 and s = 2 or 3. Hefetz and Keevash determined for r = 3 and s = 0, and Bene Watts, Norin and Yepremyan determined for r ≥ 4 and s = 0. The cases r = 5 and s = 4 or r = 6 and s = 5 were determined by Norin and Yepremyan. Jenssen showed for r = 5, 6 or 7, and s = 3, 4 or 5 respectively. The cases r = 4 and s = 1 or r = 5 and s = 2 were determined by Jiang, Peng and Wu, and Hu, Peng and Wu respectively. For r = 5, the only remaining case is s = 1. In this paper, we determine for this case. [ABSTRACT FROM AUTHOR]

The Jinjiang oyster Crassostrea ariakensis, naturally distributing in estuarine regions with low salinity, is an important economic and ecological species in China. However, studies on its genomics and population genetics remain lacking. Here, we assembled the chromosome‐level genome of a female C. ariakensis and re‐sequenced 261 individuals from five locations in China representing three typical habitats. The C. ariakensis genome was 662.9 Mb with contig N50 length of 5.9 Mb using PacBio HiFi‐CCS long reads, and 99.83% sequences were anchored onto 10 pseudochromosomes using Hi‐C data. A total of 26,354 protein‐coding genes were predicted. We identified three significantly expanded gene families which are closely associated with osmotic pressure regulation, including CDO, SLC13 and SDR. Population structure analysis revealed that the C. ariakensis from five locations were clustered into three typical groups (northern, southern and Shanghai) (K = 3) and their phylogenetic relationship was consistently correlated to their geographical distribution. Furtherly, the differentiation between northern and southern groups was clearly demonstrated by estimated population differentiation coefficient (FST = 0.1154), and the PSMC distribution showed the two groups of effective population size separated at 0.1 Ma. Meanwhile gene flow from southern to Shanghai was detected. Selective sweep analysis between northern and southern group detected genes associated with heat response and salinity adaptation. This study could provide valuable genomic resources and information for further research on the molecular evolution, genetic breeding, biological function and evolutionary adaptation of C. ariakensis. [ABSTRACT FROM AUTHOR]

In view of the compulsory merging behavior and complex driving environment in freeway work zones, the factors influencing drivers' merging behavior need to be focused on the given road environment. Realizing the need to mitigate the impact of such a challenging scenario, this study aims to explore the impact of road environment on drivers' merging location selection in freeway work zone merging areas. The survey data for modelling were collected through questionnaires survey based on the stated preference (SP) method. The logistics regression model was utilized to extract the significant factors influencing merging location selection. The results of fitting effect analysis show that the developed logistics regression models provide a good fit for the survey data. The road conditions and speed limit strategies are the significant factors affecting the drivers' preference to merging location selection in upstream transition area. The road conditions, traffic environment conditions, speed conditions, and speed limit strategies are the prominent influencing factors to the latter part of advance warning area. It is a comprehensive analysis to consider the influence of road environment on merging location selection from the perspective of drivers, which is expected to support the merging control strategy and avoid the occurrence of traffic crash in work zones. [ABSTRACT FROM AUTHOR]

In order to improve the thiourea gold leaching rate of a low-grade arsenic–sulfur-containing refractory gold ore in Xinjiang, a microbial pretreatment was used to oxidize pyrite and arsenopyrite to obtain a bio-oxidation residue. The main minerals were quartz, mica, and some sulfides that were not fully oxidized. In this study, the static adsorption method was applied to simulate the thiourea adsorption by typical minerals. The results showed that the amount of thiourea adsorbed by the three minerals could be ordered as follows: pyrite > mica > quartz. Quartz had hardly any adsorption of thiourea. The thiourea adsorption capacities of pyrite and mica were about 8.93 mg g−1 and 2.30 mg g−1, respectively. The adsorption process for pyrite conformed to the Freundlich isotherm equation and pseudo-second-order kinetic model, indicating that the adsorption process was a monolayer chemisorption. The adsorption process for mica conformed to the Langmuir isotherm equation and pseudo-second-order kinetic model, indicating that the adsorption process was a monolayer physical adsorption. Fourier transform infrared spectroscopy showed that the adsorption of thiourea on the surface of mica relied on the formation of hydrogen bonds with Si-OH, whereas a new S-S peak was detected on the surface of pyrite, which further indicated that thiourea was chemically adsorbed on the surface of pyrite. [ABSTRACT FROM AUTHOR]

Electrorefining of the high-burnup spent nuclear fuels is critical to the closed fuel cycle in fast reactors for the sustainable development of nuclear energy. However, a remaining challenge in the electrorefining process is the separation of radioactive rare earth fission products to reduce the geological waste volume. In this work, the extraction of a major radionuclide Nd from the molten waste salt into durable waste forms was investigated through a two-step approach consisting of electrolytic reduction and oxidative extraction. Liquid Bi was found to be effective in the electrolytic extraction of Nd, leading to an extraction efficiency of up to 98.6% and a current efficiency of 93.5%. The Nd target in the resulting Nd–Bi cathode alloy was then selectively extracted using specific oxidizers in a glass melting step. High loadings of Nd 2 O 3 in the converted zinc-in-titania glass ceramic and aluminoborosilicate glass waste forms were achieved, demonstrating the prospect of the proposed method in terms of minimizing radioactive waste generation and recycling of the electrorefining waste salt. [Display omitted] • A novel two-step process extracts Nd from waste salt to durable waste form. • Bi exhibits high current efficiency in electrodeposition of metallic Nd. • Nd in the Bi alloy is selectively extracted in glass melt through oxidation. • Nd is immobilized in glass/ceramic waste forms with optimal loadings. • Recycling of the salt with minimum nuclear waste generation is foreseeable. [ABSTRACT FROM AUTHOR]

Combinatorial materials chips (CMC) are composition spread thin-films deposited on a substrate that can rapidly determine the compositional-temperature information of ternary phase diagrams by high-throughput characterization. In this study, phase boundary information determined by CMC from the recent studies was used as input to optimize the thermodynamic model parameters by ESPEI based on Bayesian approach. The uncertainties in the model were also quantified. Fe–Cr–Ni and Fe–Co–Ni systems were chosen as examples to demonstrate the effectiveness of process. The newly optimized phase diagrams are in good agreement with the experimental results. It is also verified that the model can be effectively optimized by the dense CMC phase boundary data only without including the scattered experimental data. Moreover, the uncertainty in the model is reduced with the addition of CMC data. Finally, probability distributions of various phase combinations in the phase diagram were calculated, providing confidence intervals for material design. [Display omitted] [ABSTRACT FROM AUTHOR]

The interactions between water and multiscale pores affect significantly most of the physical and chemical properties of cementitious materials such as cement mortar, paste, and concrete. In this paper, molecular mechanism of multilayer water adsorption and condensation in micropores of typical cementitious minerals, the dicalcium silicate (C 2 S) and calcium silicate hydrate (C-S-H), were investigated by molecular simulations. Classical adsorption isotherm models were examined for their applicability to describe the adsorption law in molecular scales. Besides, the Kelvin equation was modified to satisfy the description of condensation at the microscale. Calculation results show that the most commonly used Brunauer-Emmett-Teller (BET) model can only describe the isotherms within a limited range of low water vapor pressures. In comparison, the modified Brunauer-Emmett-Teller-Pickett (BETP) model can describe the adsorption of water molecular on the surface of C 2 S and C-S-H more precisely, due to considering the adsorption layers as finite at saturation pressure and the reduced escape probability of the outermost layer of adsorbed water molecules. As for the condensation of water molecules in C 2 S and C-S-H slits, the traditional Kelvin equation is not applicable. Therefore, a refined Kelvin equation was proposed to describe the relationship between pore size and the pressure required for condensation accurately by considering the critical pore size, adsorption thickness, and decay rate of adsorption potential energy. Further analysis suggests that C 2 S releases more first-layer adsorption heat and thus shows stronger adsorption of water molecules compared to C-S-H. • The water adsorption isotherms of C 2 S and C-S-H are calculated by GCMC simulations. • The applicability of adsorption isotherm models are examined for cement materials. • The Kelvin equation was refined to describe condensation of water in micropores. [ABSTRACT FROM AUTHOR]

Two families A and B are called cross t -intersecting if | A ∩ B | ≥ t for all A ∈ A , B ∈ B. Let n , k , t be positive integers and A , B ⊆ ( n k ). Pyber proved that if A and B are cross 1-intersecting, then | A | | B | ≤ ( n − 1 k − 1 ) 2 for all n ≥ 2 k , and equality holds if and only if A = B = { A ∈ ( [ n ] k ) : x ∈ A } for some x ∈ [ n ] whenever n > 2 k. Frankl and Kupavskii sharpened Pyber's inequality to | A | | B | ≤ (( n − 1 k − 1 ) + ( n − i k − i + 1 )) (( n − 1 k − 1 ) − ( n − i k − 1 )) under the assumption that | B | ≥ ( n − 1 k − 1 ) + ( n − i k − i + 1 ). In this paper, firstly, we show that the families that attain this bound are unique for n ≥ 2 k + 1. Secondly, combining the result of Frankl and Kupavskii, we show that if A ⊆ ( [ n ] k ) and B ⊆ ( [ n ] k ) are cross 1-intersecting with ∩ B ∈ B B = ∅ , then | A | | B | ≤ (( n − 1 k − 1 ) − ( n − k − 1 k − 1 )) (( n − 1 k − 1 ) + 1). Lastly, we generalize the above result to cross t -intersecting families for all large n. [ABSTRACT FROM AUTHOR]

Several studies have suggested that coatomer protein complex subunit beta 2 (COPB2) may act as an oncogene in various cancer types. However, no systematic pan-cancer analysis has been performed to date. Therefore, the present study analyzed the potential oncogenic role of COPB2 using TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus) datasets. The majority of the cancer types overexpressed the COPB2 protein, and its expression significantly correlated with tumor prognosis. In certain tumors, such as those found in breast and ovarian tissues, phosphorylated S859 exhibited high expression. It was found that mutations of the COPB2 protein in kidney and endometrial cancers exhibited a significant impact on patient prognosis. It is interesting to note that COPB2 expression correlated with the number of cancer-associated fibroblasts in certain tumors, such as cervical and endocervical cancers and colon adenocarcinomas. In addition, COPB2 was involved in the transport of substances and correlated with chemotherapy sensitivity. This is considered the first pan-tumor study, which provided a relatively comprehensive understanding of the mechanism by which COPB2 promotes cancer growth. [ABSTRACT FROM AUTHOR]

Resistance to cytarabine is an important cause of therapy failure in persons with acute myeloid leukemia (AML). Deoxycytidine kinase, encoded by DCK, catalyzes phosphorylation of cytarabine to cytarabine monophosphate, a necessary step for eventual incorporation of cytarabine triphosphate into DNA and for clinical efficacy. Whether DCK mutations make AML cells resistant to cytarabine is controversial. We studied DCK mutations and messenger RNA (mRNA) concentrations in leukemia cells from 10 subjects with AML who received cytarabine-based therapy and relapsed and in 2 artificially induced cytarabine-resistant AML cell lines. DCK mutations were detected in 4 subjects with AML relapsing after achieving a complete remission and receiving high-dose cytarabine postremission therapy. Most mutations were in exons 4–6 and were not present before therapy. DCK was also mutated in cytarabine-resistant but not parental AML cell lines. DCK mRNA concentrations were significantly decreased in cytarabine-resistant K562 and SHI-1 cells compared with cytarabine-sensitive parental cells. Mutation frequency of DCK and mRNA concentration did not correlate with the extent of cytarabine resistance indicating other factors operate. Overexpression of wild-type DCK restored cytarabine sensitivity to previously resistant leukemia cell lines. Our data contribute to the understanding of cytarabine resistance in persons with AML. [ABSTRACT FROM AUTHOR]

Two photoreactions for the synthesis of 1- and 2-deoxysugars from thioglycosides were developed. In the presence of Hantzsch ester as an additive, a wide range of 1-deoxysugars were synthesized in moderate to excellent yields under irradiation with UV light without an exogenous photosensitizer. On the other hand, the utilization of 2,4,6-tri-tert-butylpyrimidine (TTBP) as the additive furnished a variety of 2-deoxysugars as the main products from their corresponding thioglycosides. The reported methodology has a broad substrate scope and high functional group tolerance and is scalable to gram-scale reaction. [ABSTRACT FROM AUTHOR]

To analyze the risk factors influencing the crash injury severity in rural-urban fringes, crash data in rural-urban fringes were collected from Harbin, China. Four risk factors, namely, time of day, vehicle type, road feature, and crash type, were investigated associated with the severity of rural-urban fringe crashes. The crash injury severity was divided into two categories, including fatal and nonfatal crash. The logistic regression was applied to explore the relationships between the severity outcomes and time of day, vehicle type, road feature, and crash type. The test methods of goodness-of-fit and badness-of-fit are conducted to examine the validity of estimation results. The results show considerable matching of the number of different crash types between calculated results and actual data. Compared with the other influencing factors, the time of day is significant factor for crash injury severity based on the study. As such, the proposed calibration procedure and the factors of choice are recommended as a validated approach to analyze and identify the main factors influencing crash injury severity in rural-urban fringes. [ABSTRACT FROM AUTHOR]

For a fixed positive integer n and an r-uniform hypergraph H, the Turán number ex(n, H) is the maximum number of edges in an H-free r-uniform hypergraph on n vertices, and the Lagrangian density of H is defined as π λ (H) = sup { r ! λ (G) : G is an H -free r -uniform hypergraph } , where λ (G) = max { ∑ e ∈ G ∏ i ∈ e x i : x i ≥ 0 and ∑ i ∈ V (G) x i = 1 } is the Lagrangian of G. For an r-uniform hypergraph H on t vertices, it is clear that π λ (H) ≥ r ! λ (K t - 1 r) . Let us say that an r-uniform hypergraph H on t vertices is λ -perfect if π λ (H) = r ! λ (K t - 1 r) . A result of Motzkin and Straus implies that all graphs are λ -perfect. It is interesting to explore what kind of hypergraphs are λ -perfect. A conjecture in [22] proposes that every sufficiently large r-uniform linear hypergraph is λ -perfect. In this paper, we investigate whether the conjecture holds for linear 3-uniform paths. Let P t = { e 1 , e 2 , ⋯ , e t } be the linear 3-uniform path of length t, that is, | e i | = 3 , | e i ∩ e i + 1 | = 1 and e i ∩ e j = ∅ if | i - j | ≥ 2 . We show that P 3 and P 4 are λ -perfect. Applying the results on Lagrangian densities, we determine the Turán numbers of their extensions. [ABSTRACT FROM AUTHOR]

Ehrenfest time depends differently on the Planck constant in integrable motion and chaotic motion. We study how its dependence on the Planck constant changes when there is a continuous transition from regular motion to chaotic motion. We find that the dependence is a weighted compromise between its two distinct dependences in regular and chaotic motions. The study is carried out with the system of periodically driven anharmonic oscillator. As the system is quite typical, the result may apply generally. [ABSTRACT FROM AUTHOR]

This is a tutorial for the many-worlds theory by Everett, which includes some of my personal views. It has two main parts. The first main part shows the emergence of many worlds in a universe consisting of only a Mach–Zehnder interferometer. The second main part is an abridgment of Everett’s long thesis, where his theory was originally elaborated in detail with clarity and rigor. Some minor comments are added in the abridgment in light of recent developments. Even if you do not agree to Everett’s view, you will still learn a great deal from his generalization of the uncertainty relation, his unique way of defining entanglement (or canonical correlation), his formulation of quantum measurement using Hamiltonian, and his relative state. [ABSTRACT FROM AUTHOR]

To study the damage of bridge pile foundations caused by scouring, two damage mechanisms of scouring are proposed in this paper. Considering the vehicle-bridge coupled vibration in terms of two aspects of the scouring depth and erosion depth, the vertical and transversal dynamic characteristics and dynamic responses of the bridge are studied under different cases for the most sensitive vehicle speed. The dynamic characteristics include the 1st and 2nd vibration modes of the vertical and transversal directions of the bridge. The dynamic responses include the vertical and transversal dynamic load allowances and acceleration of the bridge. The souring depth is more sensitive than the erosion depth, and the 2nd vertical mode is most substantially influenced by scouring and erosion. Because of the small value of the natural frequency of the vertical vibration modes, the transversal vibration modes may be more convenient to obtain. The study of the dynamic responses shows that the scouring depth can be represented by the dynamic load allowance in the middle of the span's section and the erosion depth can be characterized by the dynamic load allowance at the quarter location of the span's section. [ABSTRACT FROM AUTHOR]

Background: Effective management of imported cases is an important part of epidemic prevention and control. Hainan Province, China reported 168 coronavirus disease 2019 (COVID-19), including 112 imported cases on February 19, 2020, but successfully contained the epidemic within 1 month. We described the epidemiological and clinical characteristics of COVID-19 in Hainan and compared these features between imported and local cases to provide information for other international epidemic areas. Methods: We included 91 patients (56 imported and 35 local cases) from two designated hospitals for COVID-19 in Haikou, China, from January 20 to February 19, 2020. Data on the demographic, epidemiological, clinical and laboratory characteristics were extracted from medical records. Patients were followed until April 21, 2020, and the levels of antibodies at the follow-ups were also analysed by the Wilcoxon matched-pairs signed ranks test. Results: Of the 91 patients, 78 (85.7%) patients were diagnosed within the first three weeks after the first case was identified (Day 1: Jan 22, 2020), while the number of local cases started to increase during the third week. No new cases occurred after Day 29. Fever and cough were two main clinical manifestations. In total, 15 (16.5%) patients were severe, 14 (15.4%) had complicated infections, nine (9.9%) were admitted to the intensive care unit, and three died. The median duration of viral shedding in feces was longer than that in nasopharyngeal swabs (19 days vs 16 days, P = 0.007). Compared with local cases, imported cases were older and had a higher incidence of fever and concurrent infections. There was no difference in outcomes between the two groups. IgG was positive in 92.8% patients (77/83) in the follow-up at week 2 after discharge, while 88.4% patients (38/43) had a reduction in IgG levels in the follow-up at week 4 after discharge, and the median level was lower than that in the follow-up at week 2 (10.95 S/Cut Off (S/CO) vs 15.02 S/CO, P < 0.001). Conclusion: Imported cases were more severe than local cases but had similar prognoses. The level of IgG antibodies declined from week 6 to week 8 after onset. The short epidemic period in Hainan suggests that the epidemic could be quickly brought under control if proper timely measures were taken. [ABSTRACT FROM AUTHOR]

Hepatic stellate cells (HSC) activation and proliferation mediated the pathogenic development of hepatic fibrosis (HF). However, the underlying mechanisms remain poorly understood. In this study, we aimed to investigate the miR-29a-3p and its effects on PIK3R3 expression in HF pathogenesis. LX-2 cells treated with TGF-β1 was used as the in vitro HF model. The expression of microRNAs and proteins in LX-2 cells were detected by quantitative RT-PCR and western blotting. Then, miR-29a-3p expression in LX-2 cells were altered via transfection with specific mimics or inhibitors, followed by cell proliferation measured through CCK-8, Edu staining and colony formation. The dual luciferase reporter assay was done to assess binding of miR-29a-3p with PIK3R3 gene sequences. Moreover, PIK3R3 gene overexpression in LX-2 cell was realized through transfection with recombinant pcDNA3.0-PIK3R3 plasmids. Successful establishment of cellular HF model was validated through the increased Col-I and a-SMA expression in TGF-β1-treated LX-2 cells shown by qRT-PCR and Western blot. In such model, miR-29a-3p expression in LX-2 cells showed the greatest decrease among four candidate microRNAs in response to TGF-β1 treatment. Also, miR-29a-3p directly binds with the 3' UTR region of the PIK3R3 gene to suppress its expression in LX-2 cells. Furthermore, PIK3R3 gene overexpression effectively abrogated the changes of LX-2 cell proliferation, AKT phosphorylation and Col-I and a-SMA expression caused by miR-29a-3p mimics. MiR-29a-3p regulates hepatic stellate cell proliferation and hepatic fibrosis pathogenesis by targeting PIK3R3 expression and modulating the PI-3K/AKT signaling. • MiR-29a-3p regulates hepatic stellate cell proliferation. • MiR-29a-3p regulates hepatic stellate cell hepatic fibrosis pathogenesis by targeting PIK3R3 expression. • MiR-29a-3p regulates hepatic stellate cell proliferation and hepatic fibrosis pathogenesis by the PI3K/AKT. • These results provide a new perspective on the molecular events driving HSC proliferation and activation. [ABSTRACT FROM AUTHOR]

Real recommender systems usually contain various auxiliary information. Some of the most recent works make meaningful exploration of incorporating auxiliary information into the representation model for competitive recommendation. However, learning user and item representations still faces two challenges: (1) existing works do not well address the problem of integrating multi-type auxiliary information; (2) learning representations for inactive users is still challenging due to the high sparsity of explicit user–item associations. In order to tackle these problems, in this paper, the attributed heterogeneous network and bipartite interaction network are employed to incorporate various auxiliary information and user–item associations. A joint objective function and an efficient algorithm are devised for the representation learning. Experimental results show that the proposed algorithm has significant advantages over the state-of-the-art baselines. What is remarkable is that our proposed method is demonstrated to be especially useful for dealing with low-active users in the system. [ABSTRACT FROM AUTHOR]

Knowledge-based question answering has attracted a lot of attention in the research communities of natural language processing and information retrieval. However, existing studies do not adequately address the problem of answering complex questions which involve multiple entities and require extraction of facts from multiple relations. To address this issue, we propose a novel approach which learns the distributional representations of questions and candidate answers in a unified deep-learning framework based on directed-acyclic-graph-structured long short-term memory and memory networks. Specifically, the questions are encoded to match candidate directed acyclic subgraphs of the knowledge base, which are able to include information related to multiple entities and relations in the complex questions. The experimental results show that the proposed approach outperforms other methods on the widely used dataset SPADES, especially when dealing with complex questions with multiple entities. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we performed a simplified genome sequencing of 301 individuals from 10 populations of Ruditapes philippinarum in coastal China using restriction site-associated DNA sequencing (RAD-seq) technology, and obtained a large number of single-nucleotide polymorphism (SNP) markers of Manila clam. Eighty-eight SNP markers were successfully developed using high-resolution melting (HRM) analysis, and the genetic structure and genetic diversity of two populations were analyzed. SNP markers provide a valuable resource for population and conservation genetics studies of this commercially important species. Single-nucleotide polymorphisms (SNPs) are the most commonly used DNA markers in population genetic studies. We used the Illumina HiSeq4000 platform to develop single-nucleotide polymorphism (SNP) markers for Manila clam Ruditapes philippinarum using restriction site-associated DNA sequencing (RAD-seq) genotyping. Eighty-eight SNP markers were successfully developed by using high-resolution melting (HRM) analysis, with a success rate of 44%. SNP markers were analyzed for genetic diversity in two clam populations. The observed heterozygosity per locus ranged from 0 to 0.9515, while the expected heterozygosity per locus ranged from 0.0629 to 0.4997. The value of FIS was estimated to be from −0.9643 to 1.0000. The global Fst value was 0.1248 (p < 0.001). After Bonferroni correction, 15 loci deviated significantly from the Hardy–Weinberg equilibrium (p < 0.0006). These SNP markers provide a valuable resource for population and conservation genetics studies in this commercially important species. [ABSTRACT FROM AUTHOR]

Thermodynamic modelling of the multi-component system from the low-order subsystems in a self-consistent way and a quantitative description of the uncertainty in the modelling are critical to multicomponent alloy design. The Ag–Cu, Ag–Co, and Co–Cu binary systems are the subsystems to build the Ag–Cu–Co ternary system. They are important for the Ag–Cu-based lead-free solders and represent typical eutectic, monotectic, and peritectic systems. In this work, we present a case study of modelling and uncertainty quantification with the recently developed Extensible Self-optimizing Phase Equilibria Infrastructure (ESPEI). Enthalpies of mixing at 0 K were calculated by density functional theory (DFT)-based first-principles method using the special quasi-random structures (SQS) to compensate for the lack of thermochemical solid solution data. Incorporating the collected experimental data, the three sub-binary systems were successfully assessed, and the Ag–Cu–Co ternary system was subsequently modelled. The calculated phase diagrams of the ternary system and the sub-binary system agree with the experiments well. The reliability of the obtained models was further validated by the "residual driving force" approach. The probability distribution of the mono-variant points reside within composition-temperature space is also determined by the Phase Diagram Uncertainty Quantification (PDUQ) tool, providing confidence measures in the design of solder alloys. • Thermodynamic assessments of Ag–Cu–Co ternary and its sub-systems via the ESPEI tool. • Quantified uncertainty of the optimized model. • Demonstration of the workflow to estimate the high-order systems from the sub-systems. [ABSTRACT FROM AUTHOR]

A complete ternary phase diagram under constant pressure describes conditions of phase regions in the composition–temperature space, where the zero-phase-fraction (ZPF) features are in the form of point, curve, or surface. In this work, we propose an approach to determine the ZPF features and their uncertainty from the discrete data points on the isothermal sections at different temperatures. Domain knowledge of phase diagrams was used as prior in Bayesian statistics. The schematic and effectiveness of the developed method were demonstrated by two model systems and two actual systems. Besides, an experimentally determined Fe–Co–Ni system has been employed to demonstrate how to determine the phase boundary surfaces of the ternary system with combination of experimental data and information from the sub-binary systems. Phase boundary surfaces of the ternary system can be satisfactorily determined even with the data of only one isothermal section when coupled with the information from the sub-binary systems. [Display omitted] [ABSTRACT FROM AUTHOR]

• The α-Fe 2 O 3 /g-C 3 N 4 composite with a heterostructure was prepared, which compensates for the insufficient surface area of conventional α-Fe 2 O 3. • Through the TEM observation of the lattice spacing, the error between the theory and the experimental results is only about 2%. • The oxidation mechanism of As(III) is deduced, and the removal of As 2 O 3 by α-Fe 2 O 3 /g-C 3 N 4 can be understood as adsorption before catalysis. Arsenic has strong migration and enrichment in flue gas and can produce serious arsenic pollution, so it is urgent to control the arsenic emission in flue gas. In this study, α-Fe 2 O 3 /g-C 3 N 4 composites with heterostructure were prepared by hybrid calcination, which was innovatively used to combine As 2 O 3 (g) adsorption experiment and microscopic computational analysis. The experimental results show that FC2 (α-Fe 2 O 3 :g-C 3 N 4 = 14%, Wt%) has a better As 2 O 3 (g) adsorption capacity within 400–500 °C. At 450 °C, FC2 has almost twice the adsorption capacity of As 2 O 3 (g) than α-Fe 2 O 3 with an adsorption capacity of 2870.93 mg/kg. When the temperature rises to 500 °C, the adsorption amount of FC2 to As 2 O 3 (g) reaches 3450.80 mg/kg, which can be attributed to the more active points than α-Fe 2 O 3. At the same time, with the increase of the adsorption time, the As(III) in the sample tends to be gradually oxidized to As(V). The results of density functional theory (DFT) show that in the heterostructure of α-Fe 2 O 3 (0 0 1)/g-C 3 N 4 (0 0 2), the electron transfers 0.614 e from g-C 3 N 4 to α-Fe 2 O 3 , which establishes the electron transmission channel, thus enhancing the adsorption capacity of As 2 O 3 (g). Finally, the oxidation mechanism of As(III) is deduced, and the removal of As 2 O 3 by α-Fe 2 O 3 /g-C 3 N 4 can be understood as adsorption before catalysis. Firstly, As 2 O 3 (g) is adsorbed to Fe and O on the surface and generates chemical bonds, subsequently binding to the cleaved O 2. Part of As(III) is oxidized to As(V), and the other part of As is still As(III) although the As-O bond is broken but combines with O of O 2. [ABSTRACT FROM AUTHOR]

Narrowband light absorbers are of great importance in many practical applications, such as color filtering and thermal emission. Here, we experimentally demonstrate a multispectral narrowband light absorber based on a silicon nano-cavity coupled metallo-dielectric cavity. Seven absorption bands with excellent absorption features are achieved in the near-infrared region. Theoretical results indicate that the multi-band light absorption strongly attributes to the hybridization coupling between the optical modes of the silicon cavity and the plasmonic resonances of the metallic structure. These optical features hold the absorber with wide applications in optoelectronics. • A novel narrowband light absorber is demonstrated in a silicon nano-cavity coupled metallo-dielectric structure. • The maximal absorbance above 94% and bandwidth less than 21 nm are achieved. • Ultra-narrow bandwidth down to single-digit level (4 nm) is achieved in the calculation. • This absorber can be fabricated in large-area at low-cost by the standard technique. [ABSTRACT FROM AUTHOR]

• A method for flaw detection from noisy NDT signal based on nonconvex regularization is proposed. • The suitable choice of parameter p for the l p based sparse representation of noisy ultrasonic NDT signal is investigated. • Performance of the proposed approach is evaluated quantitatively, showing superior performance to competing methods. Ultrasonic testing has been an important tool for the detection of hidden defects in materials yet its effectiveness is usually compromised by the noise originated from both the testing system and the material being evaluated. Motivated by the prior knowledge that only a small number of defects or reflectors exist within the tested material thus the measured signal can be viewed as a linear combination of a few echoes, a signal processing method is proposed in this study where a nonconvex sparse regularization method based on l p -norm (0 < p < 1) penalty is employed to suppress noises in ultrasonic NDT signals thus enhancing the effectiveness and accuracy of flaw detection. Based on a specially designed over-complete Gabor dictionary, the nonconvex sparse regularization method is introduced to sparsely represent the noisy signal. After signal representation, noise is suppressed by a pruning operator, facilitating the identification and reconstruction of flaw-reflected echoes. The performance of the proposed method is quantitatively evaluated and compared with competing algorithms using simulated noisy ultrasonic signals in a statistical manner. Experimental results are also presented to demonstrate the effectiveness of our method. [ABSTRACT FROM AUTHOR]

High-symmetry transition-metal dichalcogenides (TMDs) have garnered substantial attention in the fields of sensors, optoelectronics, and valleytronics. However, the inherent C3 rotational symmetry of TMDs engenders highly isotropic properties, impeding their further technological progress. To overcome this limitation, we embarked on a study to investigate the effects of isotropic/anisotropic heterostructures engineering on WS2, aiming to break its C3 rotational symmetry. In this work, we designed and fabricated heterostructures composed of WS2 and ReS2 layers. Our comprehensive investigations revealed a remarkable emergence of anisotropic characteristics in excitons originating from the WS2 layers within the engineered WS2/ReS2 heterostructures. Moreover, we observed an enhancement in the valley polarizations of WS2 layers within the heterostructures, which is attributed to the reduced intervalley scattering facilitated by the WS2/ReS2 heterostructure configuration. This observation indicates the potential for leveraging heterostructure engineering to tailor and optimize anisotropic devices, thereby opening promising avenues for future applications in various technological domains. [ABSTRACT FROM AUTHOR]

Abstract Hemoglobin, the main component of haemolymph, is widely distributed in animals. Although its important oxygen transport functions has been extensively reported, studies on the immune function of hemoglobin in mollusc are few. Research on immune of hemoglobin of ark shell Scapharca broughtonii attracted more and more attention due to its ownership of erythrocyte comparing with many other shellfish. In this study, the hemoglobin cDNA of S. broughtonii was cloned by EST and RACE methods (named as SbHb ). Sequence analysis revealed that the cDNA was 946 bp in length, including an open reading frame (ORF) of 459 bp which encoded a polypeptide of 152 amino acid residues, and a 5′-untranslated region (UTR) of 313 bp, a 3′-UTR of 174 bp. Sequence and homology analysis showed that the SbHb shared similarity with that of other related species. The mRNA expression profiles of SbHb in tested tissues analyzed by quantitative real-time PCR (qRT-PCR) revealed that the mRNA of SbHb could be all detected in foot, gill, mantle, adductor muscle, haemocytes and hepatopancreas, and the highest level was found in the haemocytes, which is 163.2 times higher than that in adductor muscle. Vibrio anguillarum stimulation and hypoxia treatment both had significant impact on the expression of SbHb , which showed the same trends as increasing first to the highest at 16 h after treatment and then followed by declining. Recombinant protein of SbHb (rSbHb) was successfully obtained by prokaryotic expression, and further function analysis indicated obviously that the rSbHb had very strong phenoloxidase-like activity (PO-like activity) and it could remarkably inhibit growth of gram-negative bacteria V. anguillarum. All the data suggested that the SbHb plays a significant role in the process of antibacterial and anoxia tolerance reaction in S. broughtonii, providing the evidence that SbHb is a key immune factor. Highlights • Full length cDNA of hemoglobin in S. broughtonii ( SbHb ) and recombinant protein SbHb are obtained. • Biochemical analysis indcates that SbHb is involved in the acute phase response. [ABSTRACT FROM AUTHOR]

Mercury is a highly toxic heavy element, and anthropogenic emissions of mercury mainly originate from flue gas emissions. Photocatalytic removal of mercury from coal-fired flue gas is an environmentally friendly and efficient method. In this work, an efficient nickel ion-modified BiOIO 3 nanosheet photocatalyst was successfully synthesized via the hydrothermal method. The photocatalytic removal of mercury from flue gas experimented with illumination. This work found that nickel ion doping can regulate the oxygen vacancy concentration of BiOIO 3 , thus promoting charge carrier separation and molecular oxygen activation. The mechanism regulating the oxygen vacancy concentration was speculated to be that the introduced Ni2+ breaks the Bi O bond and forms defective oxygen vacancies. Meanwhile, the tests of optical and electrochemical properties showed that the doping of nickel ions in BiOIO 3 photocatalyst could reduce its energy band gap. For performing the verification, density functional theory (DFT) calculations were performed. The result of the photocatalytic experiment suggests that the flue gas mercury removal efficiency of BiOIO 3 with the optimum ratio of nickel doping reached 81.2%, which is higher than that of pure BiOIO 3 , 57.8%. The catalyst design scheme in this work can provide new ideas for catalyst modification, which can be widely used in environmental restoration. • An efficient nickel-doped BiOIO 3 nanosheets photocatalyst was synthesized by a simple hydrothermal method. • The best doping ratio of Ni/BiOIO 3 has an excellent photocatalytic removal of mercury from flue gas, reaches 81.2%. • The experimental results and DFT simulations revealed that the introduction of Ni ions could narrow the band gap of BiOIO 3. [ABSTRACT FROM AUTHOR]

In 1965, Motzkin–Straus established the connection between the maximum cliques and the Lagrangian of a graph, the maximum value of a quadratic function determined by a graph in the standard simplex. This connection gave a proof of the Turán’s classical result on Turán densities of complete graphs. In 1980’s, Sidorenko and Frankl–Füredi further developed this method for hypergraph Turán problems. However, the connection between the Lagrangian and the maximum cliques of a graph cannot be extended to hypergraphs. In 2009, S. Rota Bulò and M. Pelillo defined a homogeneous polynomial function of degree r determined by an r -uniform hypergraph and gave the connection between the minimum value of this polynomial function and the maximum cliques of an r -uniform hypergraph. In this paper, we provide a connection between the local (global) minimizers of non-homogeneous polynomial functions to the maximal (maximum) cliques of hypergraphs whose edges containing r − 1 and r vertices. This connection can be applied to obtain an upper bound on the Turán densities of complete { r − 1 , r } -type hypergraphs. [ABSTRACT FROM AUTHOR]

Ultrasonic pulse-echo methods for flaw detection have been widely employed as an effective strategy for nondestructive evaluation, and flaw detection plays an important role due to its ability to detect localized damage in structures. In practice, flaw damage typically occurs in a few areas in the material, resulting in only a few echoes that exist in a received signal, which motivates us to detect flaws using sparse representation methods. In this study, the noisy signal is modelled by a linear combination of modulated Gaussian pulses, which form an over-complete dictionary. The over-complete dictionary is designed such that the sparseness of the representation is expected. A robust sparse Bayesian learning framework is employed with the goal of enforcing model sparseness and reducing the source of ill-conditioning in the inversion problem for flaw detection. Useful information, including the range of frequency and bandwidth parameters of the flaw echoes, is also estimated. Based on this information, we propose a post-processing scheme for structure noise elimination and flaw detection. The capability of the proposed method is quantitatively evaluated by simulation studies and is further validated by the experimental data. [ABSTRACT FROM AUTHOR]

Deals with a study which described the electrical and magnetic characterization of amorphous alloys, iron telluride and cobalt telluride. Methodology of the study; Results and discussion; Conclusion.

Studies the photoinduced magnetic behavior of the amorphous metallic spin glass material Fe[sub3](GaTe[sub3])[sub2]. Precipitation metathesis reaction between the Zintl material K[sub3]GaTe[sub3] and FeCl[sub2]; Magnetic susceptibility of Fe[sub3](GaTe[sub3])[sub2]; Characterization of the spin glass state.

• Using two operations in extremal combinatorics to Lagrangian problems. • The first note on the BeneWatts, Norin and Yepremyan's conjecture which is very difficult. • The extremal hypergraphs of the maximum Lagrangian of t -intersecting r -graphs maybe the complete hypergraph, star, and others. What is the maximum Lagrangian of an r -uniform hypergraph that is t -intersecting? For t = 1 , the answer is complete; the case r = 3 was determined by Hefetz and Keevash in 2012, and the remaining cases r ≥ 4 were determined by Bene Watts, Norin and Yepremyan in 2018. For integers n , r , t , i with 1 ≤ t ≤ r ≤ n and 0 ≤ i ≤ r − t , let F (n , r , t , i) : = { e ∈ ([ n ] r) : | e ∩ [ t + 2 i ] | ≥ t + i } be a t -intersecting r -uniform hypergraph. Bene Watts, Norin and Yepremyan further conjectured that if an r -graph G is t -intersecting, then λ (G) ≤ max 0 ≤ i ≤ r − t lim n → ∞ λ (F (n , r , t , i)). In this paper, we confirm the conjecture for t ∈ { r − 1 , r − 2 } , and r ∈ { 3 , 4 , 5 , 6 }. [ABSTRACT FROM AUTHOR]

Inexpensive N-methyl-pyrrolidone (NMP)-based ionic liquids (ILs) are synthesized by coordinating N-methyl-pyrrolidone with anhydrous FeCl 3 or ZnCl 2 . The introduction of metal chlorides lowers the solubility of NMP for actual diesel. The obtained C 5 H 9 NO·0.3FeCl 3 IL shows remarkable extraction ability for dibenzothiophene (DBT) with Nernst partition coefficients ( k N ) above 7.5, which can be attributed to its low viscosity and bifunctional extractive groups of five-membered ring of NMP and unoccupied orbitals of Fe ion. The oxidative desulfurization of DBT using H 2 O 2 as oxidant and ILs as extractants are investigated. The scavenger experiments and electron paramagnetic resonance (EPR) measurement verify the active species is hydroxyl radical ( OH) responsible for the oxidation of DBT. FeCl 3 -based ILs show much better effects in catalyzing H 2 O 2 to generate OH than ZnCl 2 -based ILs. The process and mechanism for extraction and catalytic oxidation of DBT in an oil–ionic liquid–H 2 O 2 system are proposed. The C 5 H 9 NO·0.3FeCl 3 IL shows excellent recycling performance. After six-run experiment, there is only little loss in activity, which can be ascribed to the high solubility (18,190 ppm) of dibenzothiophene-sulfone (DBTO 2 ), the main oxidation product of DBT, in the IL. [ABSTRACT FROM AUTHOR]

A series of alkanediyl-spaced bis-bisurea ligands ( L2- L4) were synthesized and their anion coordination behavior studied. These ligands form interesting complexes with polymeric and oligomeric dihydrogen phosphate aggregates in the solid state. The ligands L2 and L3 coordinate with H2PO4- anions to form a unique molecular 'necklace' with an infinite (H2PO4-) n chain and surrounding ligand molecules. Meanwhile, two different dihydrogen phosphate-water oligomers, (H2PO4)6 ·(H2O)4 and (H2PO4)4 ·(H2O)2, were observed in the complexes with the ligands L3 and L4. In addition, solution anion binding properties of the ligands were studied by 1H NMR and UV/Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Manganese superoxide dismutase (MnSOD) is one of the key members of the antioxidant defense enzyme family, however, data regarding to the immune function of MnSOD in mollusks still remain limited now. In this study, a full-length MnSOD cDNA was identified by rapid amplification of cDNA ends (RACE) method from cDNA library of ark shell Scapharca broughtonii (termed SbMnSOD ). The cDNA contained an open reading frame (ORF) of 696 bp which encoded a polypeptide of 232 amino acids, a 5′-UTR with length of 32 bp and a 3′-UTR of 275 bp. Four putative amino acid residues (His-57, His-105, Asp-190 and His-194) responsible for manganese coordination were located in the most highly conserved regions of SbMnSOD and the signature sequence (DVWEHAYY) also existed in SbMnSOD . The deduced amino acid sequence of SbMnSOD shared high homology to MnSOD from other species. All those data revealed that the SbMnSOD was a novel member of the MnSOD family. The mRNA expression profiles of SbMnSOD in tissues of foot, gill, mantle, adductor muscle, hemocytes and hepatopancreas analyzed by quantitative real-time PCR (qRT-PCR) suggested the mRNA transcripts of SbMnSOD distributed in all the examined tissues. Importantly, Vibrio anguillarum challenge resulted in the increased expression of SbMnSOD m RNA with a regular change trend in all examined tissues, indicating SbMnSOD actively participated in the immune response process. What's more, further analysis on the antibacterial activity of the recombinant SbMnSOD showed that the fusion protein could remarkably inhibit growth of both Gram-positive and Gram-negative bacteria. The present results clearly suggested that SbMnSOD was an acute phase protein involved in the immune reaction in S. broughtonii . [ABSTRACT FROM AUTHOR]

Anion recognition between the triurea receptor and phosphate anion is demonstrated as the cross-linkage to build supramolecular polymer gels for the first time. A novel multi-block copolymer ( 3) is designed to have functional triurea groups as cross-linking units along the polymer main chain. By virtue of anion coordination between the triurea receptor and phosphate anion with a binding mode of 2:1, supramolecular polymer gels are then prepared based on anion recognition using 3 as the building block. [ABSTRACT FROM AUTHOR]

Vitellogenin (Vg), the major precursor of the egg-yolk proteins, has been found to play an immune role in fish and protochordate amphioxus, however, no study on the immune function of Vg in invertebrates has ever been studied before. In this study, the complete cDNA of Vg was identified from the scallop Patinopecten yessoensis (termed PyVg ). The cDNA contained an open reading frame (ORF) of 6888 bp, encoding a polypeptide of 2295 amino acid protein, which had an N-terminal signal peptide followed by the mature Vg. The mature Vg had the domains Vitellogenin_N, domain of unknown function 1943 (DUF1943) and von Willebrand factor type D domain (VWD) as well as the consensus cleavage site (R-X-R/K-R) and conserved motif (KTIGNAG). Tissue distribution assay revealed that PyVg transcripts were predominantly present in the ovary and hepatopancreas, and its expression profile in ovary well reflected the annual cycle of vitellogenesis. Interestingly, bacterial challenge caused a significant change in PyVg expression, hinting an involvement of PyVg in the acute phase response in P. yessoensis . Consistently, recombinant DUF1943 and VWD domains both could interact with LTA and LPS on bacterial wall, and purified native PyVg displayed a broad-spectrum antibacterial activity against both Gram-negative ( Escherichia coli and Vibrio anguillarum ) and Gram-positive bacteria ( Staphylococcus aureus ). Overall, these data indicate that Vg is a pattern recognition molecule with bacterial growth-inhibiting activity in the scallop. [ABSTRACT FROM AUTHOR]

High rate of viral replication and lacking of proofreading activity in hepatitis B virus (HBV) polymerase lead to the generation of mutations in HBV virus. Mutations in the reverse transcriptase (RT) region of HBV polymerase are demonstrated to be strongly associated with drug resistance during antiviral treatment. However, the presence of mutations as well as its clinical significance in treatment-naïve hepatitis patients (defined as pre-existing mutations) need to be further investigated. In the present study, a total of 168 serum samples from treatment-naive chronic hepatitis B (CHB) patients were collected, and the RT region of HBV polymerase was sequenced. The results showed that pre-existing mutations in the RT region of HBV polymerase were detected in 43 of 168 (25.6%) treatment-naive CHB patients within which there were no well-characterized primary nucleotide analogs (NAs) resistance sites. Three dominant sites at rt191, rt207 and rt226 were found mutant in 7(16.28%), 8(18.60%), and 14(32.56%) samples respectively among these 43 patients. No significant correlation was found between pre-existing mutations and gender, age, HBV genotype, ALT, HBeAg or HBV DNA loads. However, patients with pre-existing RT mutations under HBeAg sero-negative status exhibited decreased HBV DNA loads, which contributed to the decreased HBV DNA loads in the total HBeAg sero-negative patients. The above investigation indicated that there was a prevalence of pre-existing mutations in RT region of HBV polymerase which might affect the serum HBV DNA level in treatment-naive CHB patients. Its effects on the occurrence of NAs resistance and the prognosis after treatment need to be further investigated. [ABSTRACT FROM AUTHOR]