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The study was to establish a method for the simultaneous determination of six growth promoting antibacterial agents in premixes by ultra-high performance liquid chromatography. An acetonitrile-0.25% formic acid aqueous solution (50: 50) was used as the solvent, and the samples were pretreated by ultrasonic extraction. A 0.05 mol/L ammonium formate aqueous solution (pH value adjusted to 3.8 with formic acid)-acetonitrile was used as the mobile phase, and the samples were separated by gradient elution and C18 column. The results showed that the detection limit of six antibacterial agents was 1~10 mg/g. In the range of 2~100 mg/g of the added concentration, the peak areas of the main components of the six growth promoting antibacterial agents detected by the method had a good linear relationship, and the correlation coefficient R2 was 0.999 4~1.000 0. The average recoveries of six antibacterial agents were 92.2%~104.6%. The study indicates that the proposed method is efficient, reliable and sensitive, which can be used for the detection of growth promoting antibacterial agents in premixes. [ABSTRACT FROM AUTHOR]

5′-18O labeled RNA oligos are important probes to investigate the mechanism of 2′-O-transphosphorylation reactions. Here we describe a general and efficient synthetic approach to the phosphoramidite derivatives of 5′-18O labeled nucleosides starting from the corresponding commercially available 5′-O-DMT protected nucleosides. Using this method, we prepared 5′-18O-guanosine phosphoramidite in 8 steps (13.2% overall yield), 5′-18O-adenosine phosphoramidite in 9 steps (10.1% overall yield) and 5′-18O-2′-deoxyguanosine phosphoramidite in 6 steps (12.8% overall yield). These 5′-18O labeled phosphoramidites can be incorporated into RNA oligos by solid phase synthesis for determination of heavy atom isotope effects in RNA 2′-O-transphosphorylation reactions. [ABSTRACT FROM AUTHOR]

Functional characterization of pseudouridine (Ψ) in mammalian mRNA has been hampered by the lack of a quantitative method that maps Ψ in the whole transcriptome. We report bisulfite-induced deletion sequencing (BID-seq), which uses a bisulfite-mediated reaction to convert pseudouridine stoichiometrically into deletion upon reverse transcription without cytosine deamination. BID-seq enables detection of abundant Ψ sites with stoichiometry information in several human cell lines and 12 different mouse tissues using 10–20 ng input RNA. We uncover consensus sequences for Ψ in mammalian mRNA and assign different 'writer' proteins to individual Ψ deposition. Our results reveal a transcript stabilization role of Ψ sites installed by TRUB1 in human cancer cells. We also detect the presence of Ψ within stop codons of mammalian mRNA and confirm the role of Ψ in promoting stop codon readthrough in vivo. BID-seq will enable future investigations of the roles of Ψ in diverse biological processes. Pseudouridine sites in mRNA are detected at base resolution and functionally investigated. [ABSTRACT FROM AUTHOR]

Ions or charged vacancies drift induced by electric fields in organic–inorganic halide perovskites (OIHPs) generally contributes to distinct current–voltage hysteresis, which drives the development of resistive switching memory (RSM) devices. Here, the two-dimensional (2D) OIHP films are adopted as the switching layer to fabricate the RSM devices with a simplified photovoltaic structure. The device displays stable and low voltage resistive switching (RS) characteristics, with an on/off ratio greater than 106 and a switching voltage as low as 0.4 V. After adding a NiOx hole transport layer in a completed photovoltaic device, the fabricated RSM devices without encapsulation show reliable RS behavior with an endurance over 4 × 102 cycles and a retention time of 103 s in atmospheric conditions. Both Ag ions and iodine vacancies conductive filaments are responsible for the RS properties. This work provides a perspective for appvlication in high-performance 2D OIHP RSM devices compatible with photovoltaic behavior. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional (quasi‐2D) organic–inorganic hybrid perovskites have shown excellent ambient stability with decent photovoltaic performance. Further improvement of device level properties requires a comprehensive understanding of the performance‐limiting mechanisms such as phase segregation, ion/electron coupling conduction, and their effects on charge transport at both the micro‐ and macro‐scale. Here, space resolved investigations of Ruddlesden–Popper (RP) phases of the commonquasi‐2D perovskite are probed using two complementary methods, conducting atomic force microscopy (c‐AFM) and Kelvin probe force microscopy (KPFM). Bias‐driven photocurrent mappings obtained by c‐AFM measurements disclose local inhomogeneous conduction and hysteresis currents in quasi‐2D RP perovskites, while relatively uniform conductivity is observed on individual grains. Bias‐driven KPFM reveals that the surface average photovoltage sign is dominated by the band bending at the buried perovskite–substrate interface. The quasi‐2D RP film exhibits substantial variations in the spatial response of the photovoltage across grains and grain boundaries, which is direct evidence of the inherently benign nature of microstructures, and the final device performance. This research elucidates underlying space‐resolved photoresponse mechanisms behind the lower efficiency of quasi‐2D RP perovskites compared with the 3D perovskites, which is necessary for further development of efficient and stable 2D perovskite‐based devices. [ABSTRACT FROM AUTHOR]

Background: Circulating fibrinogen-to-albumin ratio (FAR) has been proposed as a novel inflammatory biomarker and a cardiovascular disease risk predictor. However, its prognostic value in patients with acute decompensated heart failure (ADHF) and different glycemic metabolic states remains ambiguous. Methods: A total of 1031 hospitalized patients with ADHF from January 2018 to May 2021 were included in the study. The primary endpoints were the major adverse cardiac and cerebral events (MACCEs). Patients were categorized into high-level FAR (FAR-H) and low-level FAR (FAR-L) groups based on the optimal cut-off value of FAR obtained from restricted cubic spline function analysis. The Kaplan–Meier plots and three multivariate-adjusted Cox proportional hazard models were used to determine the association between FAR and the risk of developing MACCEs in patients with ADHF at different glycemic metabolic states. Results: MACCEs occurred in 483 (46.8%) patients during a median follow-up time of 520 days. The optimal FAR cut-off value was 0.079. Upon analyzing the Kaplan–Meier plots, the incidence of MACCEs was significantly different between the FAR groups in all patients and patients with diabetes mellitus (p < 0.05). After adjusting for the confounding factors, the hazard ratio (HR) for MACCEs in the FAR-H group was 1.29 compared with the FAR-L group in all patients (Model 3: 95% CI 1.07–1.56, p = 0.007). Additionally, high FAR was associated with MACCEs in three multivariate Cox models (Model 1, HR = 1.52, 95% CI 1.17–1.96, p = 0.002; Model 2, HR = 1.46, 95% CI 1.13–1.89, p = 0.004; Model 3, HR = 1.48, 95% CI 1.14–1.92, p = 0.003) in DM patients. But no significant differences were found between the FAR groups for prediabetes mellitus (Pre-DM) and normal glucose regulation (NGR) using the three Cox models (all p-values were > 0.05). Conclusions: Elevated FAR was independently associated with poor prognosis in patients with ADHF and DM and thus could be used as a risk stratification tool and a potential therapeutic target in the future. [ABSTRACT FROM AUTHOR]

• Basic principles of commonly used deep learning architectures. • Drug–target interactions based deep learning approaches for drug repositioning. • Heterogeneous networks based deep learning approaches for drug repositioning. • Current challenges of deep learning in drug repositioning. • Possible ways to improve deep learning methods for drug repositioning. Drug repositioning is an attractive strategy for discovering new therapeutic uses for approved or investigational drugs, with potentially shorter development timelines and lower development costs. Various computational methods have been used in drug repositioning, promoting the efficiency and success rates of this approach. Recently, deep learning (DL) has attracted wide attention for its potential in target prediction and drug repositioning. Here, we provide an overview of the basic principles of commonly used DL architectures and their applications in target prediction and drug repositioning, and discuss possible ways of dealing with current challenges to help achieve its expected potential for drug repositioning. [ABSTRACT FROM AUTHOR]

The current cross-sectional study aimed to explore the relationship between work stressors and mental health in frontline nurses exposed to COVID-19. Participants were recruited from 16 general hospitals in Anhui province from February 2020 to March 2020. The general sociodemographic questionnaire, Nurse Job Stressors Scale, Simplified Coping Style Questionnaire, NEO Five-Factor Inventory, Perceived Social Support Scale, and Kessler Psychological Distress Scale were used in this study. Based on 723 valid questionnaires retrieved (100%), the total mean scores of work stressors and mental health of frontline nurses were (94.38 ± 23.42) and (22.81 ± 7.16), respectively. The results of the structural equation model showed that work stressors had an indirect positive effect (β = 0.484, P < 0.01), social support had a direct negative effect (β = −0.934, P < 0.01), personality traits had a direct positive effect (β = 0.209, P < 0.01), and positive coping style had both direct positive (β = 0.246, P < 0.01) and indirect negative effects (β = −0.873, P < 0.01) on frontline nurses' mental health. In conclusion, nursing staff can reinforce positive influences by accepting social support, adopting positive coping methods, and weakening negative influences factors to reduce or buffer their negative mental states and further reduce work stress. [ABSTRACT FROM AUTHOR]

Purpose. Cesarean scar pregnancy is an extremely rare type of ectopic pregnancy implanted in the myometrium at the site of a previous cesarean section scar. On the other hand, pregnancies are considered low implantations if they are identified in the lower third of the uterus without the sac implanted into the scar and have a better prognosis. Early diagnosis of both types of pregnancies can help avoid serious complications. This study is aimed at investigating the significance of transvaginal ultrasound in the differential diagnosis of cesarean scar pregnancies and pregnancies implanted in the lower uterus. Methods. Ninety-three patients with an average age of 32.7 years (range, 24–43 years) were enrolled in this study, including 66 cesarean scar pregnancies and 27 other pregnancies implanted in the lower uterus, and they were examined by transvaginal ultrasound. Results. We observed significant differences in the relationship between the cesarean sac and the scar, the source of the trophoblastic blood flow, and the thickness of the residual muscle between the cesarean scar pregnancy group and the lower uterus pregnancy group. We established the logistic model to improve the differential diagnosis of cesarean scar pregnancies and pregnancies implanted in the lower uterus. Conclusions. Transvaginal ultrasound is recommended in early pregnancy, especially for patients who have undergone a previous cesarean section delivery. [ABSTRACT FROM AUTHOR]

Efficient construction of medium-sized lactones has attracted considerable interest over several decades, but remains a formidable challenge in synthetic chemistry. Here, we describe an unprecedented palladium-catalysed regioselective [5 + n] cyclisation (n = 5, 6, and 7) between vinylethylene carbonates and various anhydrides. Catalytic transformation occurs under mild, room-temperature conditions and offers an exceptional substrate scope. A broad spectrum of medium-sized bislactones with skeletal diversity can be obtained easily. [ABSTRACT FROM AUTHOR]

Membranes with precise control of selective layer are designed and prepared by adjusting diffusion of solvents. Combining experiments and theoretical calculations, the formation mechanism of ion conductive membranes prepared by a non‐solvent induced phase separation (NIPS) method is found to be related to internal diffusion flux of solvent to the non‐solvent bath and external diffusion flux of non‐solvent to the casting solution. By regulating the internal and external diffusion rates via a two‐step NIPS method, a series of polybenzimidazole (PBI) porous membranes with independently controlled thin selective skin layers and highly porous support layers are fabricated, which achieve a simultaneous improvement in ion selectivity and proton conductivity. A vanadium flow battery assembled with a PBI membrane demonstrates an energy efficiency of 80% at a current density of 220 mA cm−2, which is the highest value among the reported PBI membranes. This provides a simple and effective way to fabricate membranes with well‐defined morphologies. [ABSTRACT FROM AUTHOR]

A four-fold interpenetrated Zn(II)-based coordination polymer with the chemical formula of {[Zn2(L)2(bdc)]·(H2O)2·DMF}n (1) was synthesized by solvent method using terephthalic acid (H2bdc) and N1,N1,N4,N4-tetrakis(4-(1H-imidazol-1-yl)phenyl)benzene-1,4-diamine (L) as the mixed ligands. The as-prepared complex 1 was measured via the elemental analysis and single crystal X-ray diffraction. Furthermore, due to its strong intense emission, complex 1 could be applied as luminescent sensor to sensitively detect 2,4,6-trinitrophenol (TNP), which has the characteristics of high sensitivity and selectivity. In addition, to evaluate the anti-bacterial effect of compound 1 in vitro, the P.gingivalis growth curves were measured. And the relative expression of ragA and ragB was detected by RT-PCR to reveal the mechanism of the compound in the anti-infectious activity. The potential anti-infectious criteria that has been observed in the experimental measurement has been further studied by using molecular docking technique. [ABSTRACT FROM AUTHOR]

An efficient diastereo‐ and enantioselective formal oxo‐Diels‐Alder reaction of enolizable aliphatic aldehydes and 5‐alkenyl thiazolones was developed through chiral amine catalysis. With a robust enamine activation strategy, both simple aliphatic aldehydes and a challenging aqueous acetaldehyde could participate well as competent dienophiles in the reaction. A variety of thiazole‐fused dihydropyran derivatives were facilely produced in up to 99% yield with up to >99:1 e.r. under mild conditions. Interestingly, a high dosage of the inexpensive aqueous acetaldehyde in a similar catalytic system could lead to a densely functionalized thiazolone product through a three‐component cascade reaction, suggesting a step‐wise mechanism for the established [4+2] annulation process. [ABSTRACT FROM AUTHOR]

Photothermal applications, such as therapy, imaging, and catalysis, necessitate heat sources capable of generating high temperatures under mid‐infrared (mid‐IR) illumination. However, commonly used metal nanostructures suffer from low efficiency due to their high carrier concentrations, resulting in shallow surface heating and optical range restrictions. To overcome these limitations, this work proposes a novel approach employing materials that support phonon polaritons (PhPs) as a promising paradigm for light‐controllable heat sources. The theoretical demonstration reveals that hexagonal boron nitride (hBN) nanorods can produce up to 46 times more heat compared to plasmonic gold counterparts under resonant monochromatic light. This superior heating capability stems from the unique properties of PhPs, which enable stronger field confinement and deeper penetration within the nanostructure, leading to higher efficiency by circumventing the electrostatic shielding effect associated with plasmonic heating. Furthermore, this work demonstrates that the heating performance of hBN antennas can be optimized by manipulating their size, geometry, and material loss. Notably, the use of isotopically pure hBN can triple the heat power. These findings highlight the tremendous potential of hBN antennas as light‐controllable heat sources, opening up new possibilities for IR photothermal applications by harnessing materials that support PhPs. [ABSTRACT FROM AUTHOR]

As head-media spacing decreases down to 10 nm in the current hard disk drive systems, interaction of lubricant on the disk with a flying slider becomes increasingly important. With this extremely small spacing, environmental conditions such as temperature and humidity influence the interaction in the head-disk interface and lubricant transfer between the disk surface and the slider surface. This paper describes a systematic and quantitative study on humidity effects on the amount of lubricant transfer between the disk surface and the slider surface. The lubricant transfer was proportional to absolute humidity, absolute amount of water in the system, rather than relative humidity alone. Profiles of depleted lubricant layer on the disk surface also showed that the increase in the amount of transferred lubricant was directly related to the increase in the mobility of the lubricant with higher absolute humidity rather than with relative humidity alone. [ABSTRACT FROM AUTHOR]

Enhancing the chemical stability of ion exchange membranes is essential for improving cycle life and enabling the widespread utilization of flow batteries. Although numerous studies have been devoted to generate ion exchange membranes with high efficiency and stability, the progress is heavy going, especially for the non-fluorinated ion exchange membranes. Here we describe the preparation and utilization of an aromatic poly (ether sulfone) composite ion exchange membrane for vanadium flow battery application. The ion exchange groups are constructed by fixing the phosphotungstic acid into the alkaline poly (vinyl pyrrolidone) through the acid-base reaction, while the aromatic poly (ether sulfone) is used as the matrix. The stability and performance of the prepared membrane are verified by utilizing it in a vanadium flow battery. Both in situ and ex situ oxidation stability tests demonstrate that the aromatic poly (ether sulfone) composite ion exchange membrane has excellent stability in vanadium flow battery medium. In addition, a battery with a prepared membrane exhibits a coulombic efficiency of 99.36% and an energy efficiency of 81.61% at the current density of 140 mA cm −2 . The aromatic poly (ether sulfone) composite ion exchange membrane represents a close step towards the design and construction of alternative types of membranes for battery application. [ABSTRACT FROM AUTHOR]

The abundant Watson-Crick face methylations in biological RNAs such as N1-methyladenosine (m1A), N1-methylguanosine (m1G), N3-methylcytosine (m3C), and N2,N2-dimethylguanosine (m22G) cause significant obstacles for high-throughput RNA sequencing by impairing cDNA synthesis. One strategy to overcome this obstacle is to remove the methyl group on these modified bases prior to cDNA synthesis using enzymes. The wild-type E. coli AlkB and its D135S mutant can remove most of m1A, m1G, m3C modifications in transfer RNA (tRNA), but they work poorly on m22G. Here we report the design and evaluation of a series of AlkB mutants against m22G-containing model RNA substrates that we synthesize using an improved synthetic method. We show that the AlkB D135S/L118V mutant efficiently and selectively converts m22G modification to N2-methylguanosine (m2G). We also show that this new enzyme improves the efficiency of tRNA sequencing. [ABSTRACT FROM AUTHOR]

The abundant Watson-Crick face methylations in biological RNAs such as N1-methyladenosine (m1A), N1-methylguanosine (m1G), N3-methylcytosine (m3C), and N2,N2-dimethylguanosine (m22G) cause significant obstacles for high-throughput RNA sequencing by impairing cDNA synthesis. One strategy to overcome this obstacle is to remove the methyl group on these modified bases prior to cDNA synthesis using enzymes. The wild-type E. coli AlkB and its D135S mutant can remove most of m1A, m1G, m3C modifications in transfer RNA (tRNA), but they work poorly on m22G. Here we report the design and evaluation of a series of AlkB mutants against m22G-containing model RNA substrates that we synthesize using an improved synthetic method. We show that the AlkB D135S/L118V mutant efficiently and selectively converts m22G modification to N2-methylguanosine (m2G). We also show that this new enzyme improves the efficiency of tRNA sequencing. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted great attentions due to their excellent photovoltaic performance. Further improvement of device efficiency is limited by the recombination of the charge carriers even a heterojunction-based architecture is employed. Herein, we discovered that a simple surface modification of the perovskite film by incorporating isopropyl alcohol (IPA) post-treatment could convert the top surface to be more n-type, which spontaneously formed an n/n+ homojunction between the bulk (weak n type (n)) and the surface (more n-type (n+)) in a single perovskite film. A reconstruction toward a PbI 2 -rich top surface was induced by the remove of excess formamidinium iodide dissolved in a polar solvent IPA. This reconstructed n/n+ homojunction lead to the enlarged built-in electric field for efficient charge separation and transport of the photogenerated carriers. The inverted PSCs with the reconstructed n/n+ homojunction contribute to improve efficiency and narrow their efficiency gap with conventional n-i-p type devices. Our result suggests that the homojunction structure is an effective approach to reduce carrier recombination loss and achieve highly efficient PSCs. [Display omitted] • A facile surface homojunction reconstruction is achieved by solvent treatment. • A PbI 2 -rich perovskite surface is induced by the remove of excess FAI. • The reconstructed n/n+ homojunction brings about the enlarged built-in electric field. • The reconstructed n/n+ homojunction contributes to improved photovoltaic efficiency. [ABSTRACT FROM AUTHOR]

Objective To analyze and explore the two-dimensional ultrasound combined with four-dimensional ultrasound in prenatal diagnosis of cardiac malformation. Methods From January 2011 to March 2013, 2 500 pregnant women who admitted in our hospital for prenatal screening were selected in this study. The pregnant women with suspected fetal malformations were given a separate two-dimensional ultrasound and two-dimensional ultrasound combined with four-dimensional ultrasound, the diagnostic accuracy was determined according to the pregnant woman or the fetus after birth. Results 2 500 pregnant women labored 2 517 fetuses, and 126 fetal malformations were found, in which 92 were found by single two-dimensional ultrasound detection, the diagnostic accuracy was 73.02%, 113 were found by combined detection, the diagnostic accuracy was 89.68%. The diagnostic accuracy of combined detection was significantly higher than single two-dimensional ultrasound detection (P<0.05) .17 (77.27%) fetal cardiac malformations were found by single two-dimensional ultrasound detection and 21 (95.45%) fetal cardiac malformations by combined detection. The diagnostic accuracy of fetal cardiac malformations by combined detection was significantly higher than single two-dimensional ultrasound detection (P<0.05). Conclusion Two-dimensional ultrasound combined with four-dimensional ultrasound can significantly improve the prenatal diagnosis of fetal cardiac malformation rate, and has important clinical significance in reducing birth defects, prenatal and postnatal care. [ABSTRACT FROM AUTHOR]

RNA-binding proteins control many aspects of cellular biology through binding single-stranded RNA binding motifs (RBMs). However, RBMs can be buried within their local RNA structures, thus inhibiting RNA-protein interactions. N6-methyladenosine (m6A), the most abundant and dynamic internal modification in eukaryotic messenger RNA, can be selectively recognized by the YTHDF2 protein to affect the stability of cytoplasmic mRNAs, but how m6A achieves its wide-ranging physiological role needs further exploration. Here we show in human cells that m6A controls the RNA-structure-dependent accessibility of RBMs to affect RNA-protein interactions for biological regulation; we term this mechanism 'the m6A-switch'. We found that m6A alters the local structure in mRNA and long non-coding RNA (lncRNA) to facilitate binding of heterogeneous nuclear ribonucleoprotein C (HNRNPC), an abundant nuclear RNA-binding protein responsible for pre-mRNA processing. Combining photoactivatable-ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) and anti-m6A immunoprecipitation (MeRIP) approaches enabled us to identify 39,060 m6A-switches among HNRNPC-binding sites; and global m6A reduction decreased HNRNPC binding at 2,798 high-confidence m6A-switches. We determined that these m6A-switch-regulated HNRNPC-binding activities affect the abundance as well as alternative splicing of target mRNAs, demonstrating the regulatory role of m6A-switches on gene expression and RNA maturation. Our results illustrate how RNA-binding proteins gain regulated access to their RBMs through m6A-dependent RNA structural remodelling, and provide a new direction for investigating RNA-modification-coded cellular biology. [ABSTRACT FROM AUTHOR]

Objective To compare the effect of initial periodontal treatment on level changes of serum proinflammarry factors in patients with coronary heart disease combined with chronic periodontitis. Methods Eighty coronary heart disease patients with moderate/severe periodontitis were recruited and divided into two groups randomly. The experimental group was treated with the routine medicine plus initial periodontal treatment, while the control group treated with the routine treatment only. Periodontal clinical index, detective radio of putative periodontopathic bacteria and serum IL-1 β and TNF-α level were observed 8 weeks after periodontal therapy, respectively. Results All patients demonstrated improvement of periodontal clinical index and the relevance ratio of putative periodontopathic bacteria decreased. The level of IL-1β and TNF-α in experimental group decreased significantly. Conclusion Initial periodontal treatment can reduce the occurrence risk significantly from different ways, which is helpful to the prevention and treatment of CHD. [ABSTRACT FROM AUTHOR]

In scientific computing, Sparse Matrix Vector Product (SMVP) is an important calculation kernel, and its efficiency is mainly determined by the storage model and the corresponding SMVP algorithm. For the sake of obtaining better performance in the storage model of sparse matrix, based on the Huffman coding, we optimize the BCRS(Block Compressed Row Storage) method so as to reduce the storage of redundant zeros to some extent. And propose the corresponding SMVP algorithm. Theoretical analysis and experiments show that the new Huffman coding based BCRS method outperforms the two traditional BCRS methods in data complexity. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the clinical and radiological efficacy as well as safety profiles of Anbainuo, a recombinant human TNFRII:Fc fusion protein, combined with methotrexate (MTX) versus MTX alone or Anbainuo alone in the treatment of Chinese patients with moderate to severe rheumatoid arthritis (RA). In this 24-week, multicenter, double-blind, active comparator-controlled study, 396 RA patients were randomized into combination therapy group (Anbainuo plus MTX), Anbainuo group, or MTX group. Clinical response was assessed using the American College of Rheumatology (ACR)-N, ACR20, ACR50, ACR70, and van der Heijde modification of Sharp score, among which ACR-N and ACR20 were defined as primary major endpoints. After 24 weeks of treatment, the ACR-N in the combination therapy group (12.79 ± 9.24 %) was significantly higher than that in Anbainuo group (9.56 ± 11.16 %) and in MTX group (5.08 ± 11.1 %) ( p = 0.00 and p = 0.00, respectively). Patients in Anbainuo group had significantly higher ACR-N than those in MTX group ( p = 0.02). More patients in the combination therapy group (53.6 %) achieved ACR50 improvement response than those in the MTX group (30.8 %). ACR70 of combination therapy group (27.7 %) was significantly higher than that of Anbainuo group (15.8 %) and MTX group (7.70 %), with no significant difference between Anbainuo group and MTX group. DAS28-ESR in the combination therapy group was significantly reduced compared to either monotherapy groups. Moreover, DAS28-ESR was significantly lower in Anbainou group than in MTX group. The combination therapy group also showed significantly less radiographic progression than the MTX group ( p = 0.03). The total adverse events (AE) in the combination group (40.9 %) was significantly higher than those in the MTX group (28.8 %) ( p < 0.05). Anbainuo combined with MTX therapy can effectively control the disease activity and radiographic progression of RA, while the incidence of AE also increased compared to either Anbainuo or MTX. [ABSTRACT FROM AUTHOR]

We demonstrate metamaterials operating in the near-visible regime based on two-dimensional arrays of gold-coated silicon nanopillars. The nanopillar arrays demonstrate a cutoff response at the metamaterial plasma frequency in accordance with theory and can be utilized for filtering applications. A plasma frequency in the near visible region of λ = 1 μm is calculated numerically for an array with a lattice constant of 300 nm and wire radius of 50 nm, with reflection measurements in agreement with numerical calculations. Such structures can be utilized for achieving negative-index based metamaterials for the visible spectrum. [ABSTRACT FROM AUTHOR]

Abstract: As an important step of the active demethylation of 5-methylcytosine (5mC), human thymine DNA glycosylase (hTDG) efficiently excises 5-carboxylcytosine (5caC) from double-stranded DNA (dsDNA). Here, we present synthesis of DNA oligos containing a 2′-deoxy-2′-fluoro-d-arabinofuranosyl-5-carboxylcytidine (F-5caC) modification that act as hTDG inhibitors. The glycosylase activity assay showed that F-5caC oligos were resistant to excision by the hTDG catalytic domain (hTDGcat, residues 111–308) and they could inhibit the excision of DNA oligos containing 5caC. The electrophoretic mobility shift assay confirmed that DNA oligos containing F-5caC could bind well with unmodified hTDGcat to form a stable complex, which makes it possible to obtain the crystal structure of the complex to reveal details on how hTDGcat recognizes the DNA substrate. [Copyright &y& Elsevier]

The 2'-hydroxyl groups within RNA contribute in essential ways to RNA structure and function. Previously, we designed an atomic mutation cycle (AMC) that uses ribonucleoside analogues bearing different C-2'-substituents, including --OCH3 -- NH2 -- NHMe, and --NMe2 to identify hydroxyl groups within RNA that donate functionally significant hydrogen bonds. To enable AMC analysis of the nucleophilic guanosine cofactor in the Tetrahymena ribozyme reaction and at other guanosines whose 2'-hydroxyl groups impart critical functional contributions, we describe here the syntheses of 2'-methylamino-2'-deoxyguanosine (GNHMe) and 2-N,N-dimethylainino-2'-deoxyguanosine (Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) and their corresponding phosphoramidites. The key step in obtaining the nucleosides involved SN2 displacement of 2'-β-triflate from an appropriate guanosine derivative by methylamine or dimethylamine. We readily obtained the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. phosphoramidite and incorporated it into RNA However, the G-NHMC phosphoramidite posed a significantly greater challenge due to lack of a suitable -2'-NHMe protecting group. After testing several strategies, we established that allyloxycarbonyl (Alloc) provided suitable protection for 2'-N-methylamino group during the phosphoramidite synthesis and the subsequent RNA synthesis. This work enables AMC analysis of guanosine's 2'-hydroxyl group within RNA. [ABSTRACT FROM AUTHOR]

Two simple intramolecular charge transfer compounds (BzBMN and BzFAN), derived from 2-benzyloxy-4-diethylaminobenzaldehyde, have been synthesized. Unlike typical AIEE molecules, the enhanced emission of these compounds in the solid state is accompanied by large red shifts in emission wavelength. Absorption and photoluminescence (PL) spectra of the compounds in solution, film and the X-ray single crystal structures were investigated to understand the mechanism of enhanced emission in the solid state. The results indicate that the bathochromic shift excimer-like emissions originated from dimers induced by the dipole–dipole interaction and long-range ordered arrangement (e.g. J-aggregation), and the enhanced emission is attributed to the restriction of intramolecular rotations caused by multiple intermolecular hydrogen bonding interactions. In addition, it was also observed that BzBMN and BzFAN can facilely form single crystal microbelts and microtubes by a simple reprecipitation method. [ABSTRACT FROM AUTHOR]

To better understand the interactions between catalysts and transition states during RNA strand cleavage, primary 18O kinetic isotope effects (KIEs) and solvent D2O isotope effects were measured to probe the mechanism of base-catalyzed 2'-O-transphosphorylation of the RNA dinucleotide 5'-UpG-3'. The observed 18Q KIEs for the nucleophilic 2'-O and in the 5'-O leaving group at pH 14 are both large relative to reactions of phosphodiesters with good leaving groups, indicating that the reaction catalyzed by hydroxide has a transition state (TS) with advanced phosphorus-oxygen bond fission to the leaving group (18kLG = 1.034 ± 0.004) and phosphorus-nucleophile bond formation (18kNUC = 0.984 ± 0.004). A breakpoint in the pH dependence of the 2'-O-transphosphorylation rate to a pH independent phase above pH 13 has been attributed to the pKa of the 2'-OH nucleophile. A smaller nucleophile KIE is observed at pH 12 (18kNUC = 0.995 ± 0.004) that is interpreted as the combined effect of the equilibrium isotope effect (ca. 1.02) on deprotonation of the 2'-hydroxyl nucleophile and the intrinsic KIE on the nucleophilic addition step (ca. 0.981). An alternative mechanism in which the hydroxide ion acts as a general base is considered unlikely given the lack of a solvent deuterium isotope effect above the breakpoint in the pH versus rate profile. These results represent the first direct analysis of the transition state for RNA strand cleavage. The primary 180 KIE results and the lack of a kinetic solvent deuterium isotope effect together provide strong evidence for a late transition state and 2'-O nucleophile activation by specific base catalysis. [ABSTRACT FROM AUTHOR]

Flow batteries are one of the most promising techniques for stationary energy storage applications, benefiting from their high safety, high efficiency and long cycle life. As a key component of flow batteries, an ion conductive membrane (ICM) plays a vital role in isolating active species from anolyte and catholyte, while transferring charge careers to complete the internal circuit. Therefore, the final battery performance is largely determined by the properties of ICMs such as ions selectivity, conductivity and stability. Thus, transport behavior of different ions through ICMs will be critical to the design of high-performance flow batteries. Plenty of membranes with different structures have been developed in flow batteries, however, the ions transport mechanism in different membranes was rarely summarized. In this review, a brief introduction on ICMs will be firstly given and then the ions transport mechanism in different membranes will be summarized in detail. This review is expected to provide important guidance for the design of membranes for flow batteries. [Display omitted] • The microstructure and design of ion conductive membranes. • The ion transport mechanism of ion conductive membranes. • The structure-performance relationship of ion conductive membranes in flow batteries. • The current limitation and future directions for ion conductive membranes. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 and ZrO2-coated TiO2 working electrodes were produced and calcined at 450 °C in a 2.45 GHz microwave furnace prior to incorporation in dye-sensitized solar cells. The bare TiO2 working electrodes increased from 0.2% up to 2.4% efficient after microwave calcination at a light intensity of 1 Sun. The efficiency was further increased to 3.1% for the ZrO2-coated TiO2 core-shell electrodes. The increased photovoltaic performance was due to improvements in the open circuit voltage (V oc) from 692 to 719 mV and the short circuit current density (J sc) from 6.24 to 6.56 mA cm−2. To cite this article: David B. Menzies et al., C.R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: High-performance dye-sensitized solar cells incorporating electrochemically stable non-volatile electrolytes are especially desirable devices. In particular, ionic liquid systems based on ethylmethylimidazolium dicyanamide seem to be promising for this purpose. These have triggered our interest in the properties of further ethylmethylimidazolium-based ionic liquids with anions which are close relatives of dicyanamide. In this study, the effect of three different anions, tricyanomethanide, dicyanamide and thiocyanate, on the performance of dye-sensitized solar cells have been investigated. Both the short circuit photocurrent and conversion efficiency are increased with decreasing viscosity of the ionic liquids under comparable conditions. A conversion efficiency of 2.1% at 30% light intensity was observed for the cell containing the tricyanomethanide salt, which has lowest viscosity among the three ionic liquids, while efficiencies of 0.7% and 1.7% at the same light intensity were observed in the case of dicyanamide and thiocyanate salts, respectively, as an electrolyte. To cite this article: Q. Dai et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: N 1-Aryl derivatives of 2′-deoxyguanosine (dG) were synthesized by copper(II)-mediated coupling of dG with arylboronic acids. Analogous aryl derivatives of 2′-deoxyinosine (dIn), 2′-deoxyuridine (dU), thymidine (T), 2′-deoxyadenosine (dA), and 2′-deoxycytidine (dC) were also conveniently synthesized by this method. Arylation took place preferentially on the amido functions in dG and dIn and the imino functions in dU or T. Remarkably, the nucleosides themselves served as internal ligands as well as reactants. [Copyright &y& Elsevier]

Abstract: 2′-Amino-2′-deoxynucleosides and oligonucleotides containing them have proven highly effective for an array of biochemical applications. The guanosine analogue and its phosphoramidite derivatives have been accessed previously from 2′-amino-2′-deoxyuridine by transglycosylation, but with limited overall efficiency and convenience. Using simple modifications of known reaction types, we have developed useful protocols to obtain 2′-amino-2′-deoxyguanosine and two of its phosphoramidite derivatives with greater convenience, fewer steps, and higher yields than reported previously. These phosphoramidites provide effective synthons for the incorporation of 2′-amino-2′-deoxyguanosine into oligonucleotides. [Copyright &y& Elsevier]

Abstract: A series of new electrolyte materials based on a molecular plastic crystal doped by different iodide salts together with iodine have been prepared and characterized by thermal analysis, ionic conductivity, electrochemical and solid-state NMR diffusion measurements. In these materials, the plastic crystal phase of succinonitrile acts as a good matrix for the quaternary ammonium based iodides and iodine and appears to act in some cases as a solid-state “solvent” for the binary dopants. The materials were prepared by mixing the components in the molten state with subsequent cooling into the plastic crystalline state. This resulted in waxy-solid electrolytes in the temperature range from −40 to 60 °C. The combination of structural variation of the cations, and fast redox couple diffusion (comparable with liquid-based electrolytes), as well as a high ionic conductivity of up to 3×10−3 S cm−1 at ambient temperature, make these materials very attractive for potential use in solid-state photoelectrochemical cells. [Copyright &y& Elsevier]

Syntheses are reported for: (1) adducts of the quinone metabolites of benzo[a]pyrene (BPQ) and benz[a]anthracene (BAQ) with 2′-deoxyadenosine and 2′-deoxyguanosine; (2) 15 N-labelled analogs of these adducts (four or five nitrogen atoms 15 N-labelled); (3) depurinated adducts of BPQ and BAQ with adenine or guanine covalently linked to the N7 or N9 positions of the purine bases; (4) 13 C-labelled derivatives of benzo[a]pyrene, BPQ, benzo[a]pyrene trans-7,8-dihydrodiol, and the benzo[a]pyrene anti-diol epoxide (with 13 C-atoms at the 5- and 11-positions); and (5) depurinated adducts formed by reactions of the benzo[a]pyrene radical-cation at the C 8 -, N 7 -, and N 9 -positions of adenine and guanine. [ABSTRACT FROM AUTHOR]

To achieve disk drive recording densities greater than one terabit per square inch, future head-media spacings (HMSs) will need to be less than 7 nm. This will place severe demands on the metrology tools used to measure the thickness and topographies of the contributors to the head-media spacing. Here, we first review some of the metrologies used for characterizing overcoats, lubricants, and topographies and discuss some of the limits that will make it difficult to achieve a sub-7-nm HMS. We next show new results for measuring lubricant redistribution on disk surfaces after contact with a small pad on the slider and present a new method for determining wear rates of these slider contact pads. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulation would be well suited to predict the physics of molecularly-thick lubricants on magnetic disk surfaces. The difficulty in defining suitable interatomic potentials, as well as the requirement for large computing power, makes this type of study difficult. Treating the lubricant film in the framework of fluid dynamics has proven a much better way to model its behavior. This paper describes a full numerical model of lubricant moguls and ripples formation using finite difference analysis. We demonstrate that both moguls and ripples result from slider-induced air shear. Ripples tend to form at higher disk speed and narrower slider width, whereas moguls are seen at lower speed and larger slider width. Both moguls and ripples are enhanced for thicker lubricants, higher waviness, and lower flying heights. Ripple instabilities that were predicted earlier using a stability analysis are also quantitatively confirmed using this numerical model. [ABSTRACT FROM AUTHOR]

Concerted activation of different voltage-gated Ca2+ channel isoforms may determine the kinetics of insulin release from pancreatic islets. Here we have elucidated the role of R-type Cav2.3 channels in that process. A 20% reduction in glucose-evoked insulin secretion was observed in Cav2.3-knockout (Cav2.3 -/-) islets, close to the 17% inhibition by the R-type blocker SNX482 but much less than the 77% inhibition produced by the L-type Ca2+ channel antagonist isradipine. Dynamic insulin-release measurements revealed that genetic or pharmacological Cav2.3 ablation strongly suppressed second-phase secretion, whereas first-phase secretion was unaffected, a result also observed in vivo. Suppression of the second phase coincided with an 18% reduction in oscillatory Ca2+ signaling and a 25% reduction in granule recruitment after completion of the initial exocytotic burst in single Cav2.3 -/- β cells. Cav2.3 ablation also impaired glucose-mediated suppression of glucagon secretion in isolated islets (27% versus 58% in WT), an effect associated with coexpression of insulin and glucagon in a fraction of the islet cells in the Cav2.3 -/- mouse. We propose a specific role for Cav2.3 Ca2+ channels in second-phase insulin release, that of mediating the Ca2+ entry needed for replenishment of the releasable pool of granules as well as islet cell differentiation. [ABSTRACT FROM AUTHOR]

Three mechanisms have been proposed to explain the carcinogenic activities of polycyclic aromatic hydrocarbons (PAHs). On the basis of the nature of the active metabolites involved, they may be termed: the diol epoxide mechanism, the quinone mechanism, and the radical-cation mechanism. In connection with studies to evaluate the relative importance of these pathways, we required practical methods for the syntheses of the active PAH metabolites involved. We now report efficient new synthesis of the o-quinones of benzo[a]pyrene (BPQ), 7,12-dimethylbenz[a]anthracene (DMBAQ), and benz[a]anthracene (BAQ). These quinones are convenient synthetic precursors of the related o-catechols, trans-dihydrodiols, and diol epoxides, as well as the stable adducts of the o-quinones with 2-deoxyadenosine and 2′-deoxyguanosine. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To develop a noninvasive method and device to determine intravariceal pressure and variceal wall tension by measuring the variables of the Laplace equation and test this device in a model of esophageal varices.METHODS: Two variceal pressure measurement devices were constructed. The first device consists of an Olympus 20 MHz ultrasound transducer placed next to a latex balloon catheter attached to a pressure transducer. The second device was constructed by placing the same ultrasound transducer inside a latex condom balloon attached to a pressure transducer. These pressure measurement devices were tested blindly in varix models with different intravariceal pressures, by inflating the balloon to flatten the varix models. Each variceal pressure was measured 10 times by two separate investigators blinded to the actual pressures. The mean intravariceal pressures were calculated. The variceal models were made of a latex balloon filled with water and coffeemate.RESULTS: The correlation coefficient between the actual and measured varix pressures for both devices was 0.99. The percent error ranged from 0 to 10%. The correlation coefficient between the investigators making the blinded measurements for both devices was 0.98.CONCLUSION: Two pressure-measuring devices were developed to determine intravariceal pressure in a model varix system. These devices demonstrate a low percent error and a high correlation to the actual variceal pressures with low intra- and interobserver variability. These devices have the potential to measure all the variables of the Laplace equation for wall tension. We plan to test these devices in human subjects. [ABSTRACT FROM AUTHOR]

Polypropylene hollow fiber membranes grafted with poly(acrylic acid) were used for water–ethanol separation by pervaporation. The effects of grafting degree of poly(acrylic acid) (PAA), the cross-linking degree of the grafted-PAA, the sodium counter-ions as well as the operation temperature and the ethanol concentration in feed mixtures on pervaporation properties were investigated. It was found that water-permselective pervaporation membranes could be prepared by the grafting polymerization of acrylic acid on microporous polypropylene hollow fiber membrane surface. The separation factor increased with the increase of grafting degree of PAA in the range of 20–70 wt.%. Incorporating counter-ions as well as multifunctional comonomer into the grafted chains could improve the selectivity but sacrificed the permeation flux. The separation factor of the counter-ion containing membrane decreased according to the sequence Al3+ > K+ > Ca2+ > Na+ > Li+ and the permeation flux increased following the sequence Al3+ < Ca2+ < K+ < Na+ < Li+. Remarkable increase in permeation flux without decrease in separation factor was observed for Al3+ as counter-ion in this membrane. These results might be ascribed to the increase of packing density and the decrease of swelling degree of grafted layer on the membrane surface. [Copyright &y& Elsevier]

Reasonably high stable photocurrents, with quantum yields up to Φ=0.52 are observed using TiO2 photosensitized by adsorbed anthocyanin dyes with iodide/iodine in water at pH 1. The respective yields in pure ethanol are usually somewhat lower, up to Φ=0.33. Open circuit photovoltage up to 0.47 V in ethanol and 0.38 in water are obtained. The effects of changing charge carrier concentrations and pH, as well as the photocurrent spectra and yields under various conditions are reported. These simple systems show relatively high quantum yields of the photocurrents, as well as good stability when acidic aqueous solutions of the charge carriers are employed. Comparable yields are obtained in ethanol solutions, although some of the dyes quickly deteriorate. [Copyright &y& Elsevier]

Studies the mechanism of beta-hydride elimination in adsorbed alkoxides. Formation of fluorinated ethoxides through the adsorption of the fluorinated ethanols FmCH3-nCH2OH (n = 0-3). Lowering of the rates of beta-hydride elimination; Measurements of the equilibrium constants; Effect of fluorination of the formation of the ethoxides; Destabilization of the transition state.

Hypokalemia and hyponatremia are common but easily ignored adverse events in treatment with voriconazole (VCZ) that can lead to serious consequences. We intend to investigate the incidence of VCZ‐induced hypokalemia and hyponatremia and their risk factors based on real‐world data. A prospective study was conducted. A total of 272 patients with 414 VCZ plasma trough concentrations (C0) and VCZ N‐oxide concentrations (CN) were included. The incidence of hypokalemia was 18.0% (48/266). A total of 81.2% (39/48) of patients developed hypokalemia within 14 days, whereas 56.2% (27/48) of patients developed hypokalemia within 1 week. The proportion of female patients in the hypokalemia group was higher than that in the nonhypokalemia group, as was the proportion of patients receiving intravenous VCZ. In the multivariate analysis, the independent risk factors for hypokalemia were sex, combined use of antibiotics, and VCZ CN/C0. The incidence of hyponatremia was 7.9% (21/266). The proportion of patients over 47 years of age in the hyponatremia group was 71.4% (15/21). The number of days of VCZ use in the hyponatremia group was greater than that in the nonhyponatremia group. A total of 47.6% (10/21) of patients in the hyponatremia group had supratherapeutic VCZ C0 (>5.0 µg/mL). In conclusion, hypokalemia is more likely to occur in females, in patients receiving intravenous VCZ, and in patients with the combined use of antibiotics. Hyponatremia is more likely to occur in patients older than 47 years who have been using VCZ for a long time and have higher VCZ C0 values. [ABSTRACT FROM AUTHOR]

Patient: Female, 70-year-old Final Diagnosis: Chemical burn in the oral cavity Symptoms: Heightened salivation * intense burning sensation * oral edema Clinical Procedure: -- Specialty: Dentistry Objective: Rare disease Background: Chemical burns in the oral cavity, although rare, cause more severe tissue damage than thermal burns, continuing tissue destruction even after removing the causative substance. Prompt identification of the substance, exposure extent, time from injury to treatment, and the injured area are imperative for effective management. This report details severe oral burns in an elderly woman from accidental NaOH ingestion. Case Report: A 70-year-old female patient was presented to our hospital approximately 15 h after inadvertent consumption of approximately 20 ml of NaOH (sodium hydroxide) solution. This incident led to oral discomfort and restricted mouth opening. The ingested solution, erroneously assumed to be a beverage, was later identified as a potent alkaline substance typically employed in grease removal. Initial manifestations included intense burning sensation, oral edema, and heightened salivation, which exacerbated on the following day, adversely impacting her alimentation and verbal communication. Clinical examination disclosed extensive damage to the oral mucosa. The diagnosis encompassed a chemical burn in the oral cavity coupled with chronic gastritis. The treatment regimen comprised dietary limitations, administration of famotidine for gastric acid suppression, intravenous hydration, nutritional support, oral care with Kangfuxin liquid, and nebulization therapy. Six months after therapy, she exhibited complete recovery, with the absence of discomfort and restored normal oral functions. Conclusions: Timely and targeted treatment strategies, particularly nebulization medication and Kangfuxin liquid, are effective in managing chemical burns in the oral cavity, promoting wound healing, and preventing complications. [ABSTRACT FROM AUTHOR]

5‐Formylcytosine (f5C) modification is present in human mitochondrial methionine tRNA (mt‐tRNAMet) and cytosolic leucine tRNA (ct‐tRNALeu), with their formation mediated by NSUN3 and ALKBH1. f5C has also been detected in yeast mRNA and human tRNA, but its transcriptome‐wide distribution in mammals has not been studied. Here we report f5C‐seq, a quantitative sequencing method to map f5C transcriptome‐wide in HeLa and mouse embryonic stem cells (mESCs). We show that f5C in RNA can be reduced to dihydrouracil (DHU) by pic‐borane, and DHU can be exclusively read as T during reverse transcription (RT) reaction, allowing the detection and quantification of f5C sites by a unique C‐to‐T mutation signature. We validated f5C‐seq by identifying and quantifying the two known f5C sites in tRNA, in which the f5C modification fractions dropped significantly in ALKBH1‐depleted cells. By applying f5C‐seq to chromatin‐associated RNA (caRNA), we identified several highly modified f5C sites in HeLa and mouse embryonic stem cells (mESC). [ABSTRACT FROM AUTHOR]

With the continuous construction of urban traffic roads, more and more new roads are cut off by existing roads to form "dead end roads". There is an urgent need for a trenchless method suitable for urban ultra-shallow overburden to build the undercrossing tunnel. To solve this problem, this paper proposed the micro pipe jacking and joint assembly structure (MPJ & JAS) method, which has the characteristics of shallow burial depth, low cost, short construction time, flexible cross-section setting and high space utilization. The MPJ & JAS method construct a large cross-section tunnel through assembling small cross-section elements, quite different from traditional methods. Therefore, this paper designed a CT-shaped integrated joint, the mechanical performance of which was verified and clarified by tensile test. The bending test and finite element (FE) analysis proved the reliability of MPJ & JAS tunnel structure, and confirmed the structure performances such as the failure models, crack behaviors, load–deflection response and stress–strain distribution. Moreover, the influences of the steel plate thickness, concrete strength and shear connector spacing were determined by the FE analysis. On the basis of test results and reasonable assumptions, a theoretical design method considering the influence of the CT-shaped integrated joint was proposed, which can effectively predict the bending strength of the MPJ & JAS tunnel structure with an error of less than 10%. Finally, in view of the characteristics of the MPJ & JAS method, the suitable micro pipe jacking machine, soil reinforcement measure, hydraulic traction construction technology, high-precision guidance system and concrete construction quality detection method based on the phased array ultrasonic imaging technology were developed, supporting the accurate and efficient construction of the MPJ & JAS tunnel. [ABSTRACT FROM AUTHOR]

• Three typical vertical structures of shipping supply chain are considered. • A bilateral bargaining model is applied to vertical structure evolution. • Values of the vertical structure are analyzed under different parameter environment. • Evolution regularities are derived through the consistency of structural preferences. Fierce port competition and asymmetric bargaining power may lead to multiple vertical cooperation patterns between ports and shipping companies. The value analysis of vertical cooperation and structure preference are crucial to the evolution regularity of shipping supply chains. In a two-tier shipping supply chain consisting of competitive ports and shipping companies, we propose three typical vertical structures of shipping supply chain: port-shipping alliance, vertical integration, and cross-berthing. We show that the port-shipping alliance has the advantages of low freight rate and high throughput, but may reduce the overall performance of the shipping system. Although vertical integration helps to weaken service competition and enhance the monopoly of ports, it increases the freight rate and reduces the throughput. Cross-berthing increases the pricing power and throughput of ports, but it will bring fierce internal competition. With the increasing bargaining power of shipping company and the degree of port competition, the vertical structure evolves from the port-shipping alliance and cross-berthing to the structure with only cross-berthing, and finally turns into vertical integration. From the perspective of the overall shipping system, each evolution stable state will achieve the Pareto-optimization. [ABSTRACT FROM AUTHOR]