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Background: The objective is to analyze and review the clinical, laboratory, and neuroimaging characteristics of rheumatoid meningitis (RM) in six patients with known rheumatoid arthritis (RA). Methods: We performed a retrospective review of patients diagnosed with RM from August 2012 to June 2023. To identify the cases, we used medical term search engines and the hospital´s radiology case database. Clinical information and laboratory findings were gathered from the medical records. A neuroradiologist with five years of experience reviewed and analyzed the RM to determine the characteristics findings of RM. Results: Six patients with RM are included. Seizures along with headaches were among the clinical signs that were documented. All the patients had high levels of rheumatoid factor (RF) and anti-cyclic citrullinated peptides (ACPA) in the peripheral blood. Biopsy in two cases confirmed typical rheumatoid nodules. Leptomeningeal enhancement was found bilaterally in all cases and was predominantly found in the frontoparietal region. "Mismatch DWI/FLAIR" was found in five patients. Bilateral subdural collections could be found in two patients. Brain PET scan revealed increased metabolism in two cases. Conclusion: Rheumatoid meningitis is a rare complication of rheumatoid arthritis (RA) with challenging clinical diagnosis due to non-specific symptoms. This study highlights the importance of MR in detecting characteristic neuroimaging patterns, including "mismatch DWI/FLAIR", to aid in early diagnosis. Increased awareness of this condition may facilitate timely intervention and improve prognosis. These results still need to be verified by large studies. [ABSTRACT FROM AUTHOR]

The triazolate-assisted asymmetric dinuclear oxovanadium(IV) citrate [V2O2(cit)(Hdatrz)3]·5H2O (1, H4cit = citric acid, Hdatrz = 1H-1,2,4-triazole-3,5-diamine) and its additive salt [V2O2(cit)(Hdatrz)3][V2O2(cit)2]½·2H2datrz·9.5H2O (2) and the polymerized hexanuclear product [V6O6(μ3-O)2(cit)2(Hdatrz)4]·4H2O (3) have been isolated at different temperatures, respectively. Adduct 2 shows strong evidence for the conversion of a symmetric dinuclear oxovanadium(IV) citrate to a mixed-ligand asymmetric oxovanadium(IV) citrate. Moreover, a fully oxidized trinuclear vanadium(V) species [V3O6(μ2-OH)(μ3-O)(Hdatrz)2]·4.5H2O (4) has also been isolated as a quasi-intermediate product of 3 without the coordination of citrate. Intriguingly, an octanuclear mixed-valence oxovanadium(V / IV) citrate K2{[V IV/V2 O2(cit)(Hdatrz)(datrz)]2[V IV2 O2(cit)(Hdatrz)(datrz)]2}·27.5H2O (5) has been obtained with different vanadium units, where dinuclear mixed-ligands and mixed-valence oxovanadium(IV / V) citrates [V IV/V2 O2(cit)(Hdatrz)(datrz)] (5a) and [V IV2 O2(cit)(Hdatrz)(datrz)] (5b) have been trapped. Citrate adopts a μ2-η1:η1:η1:η2 coordination mode in 1, 2 and 5, while a μ3-η1:η1:η1:η2 fashion has been observed in 3. Unlike 1–4, complex 5 contains both protonated and deprotonated triazolates simultaneously, where four triazolates further coordinate in a μ3-η1:η1:η1 manner to construct an octanuclear unit. These different structural features in 1–5 are dominated by flexible multidentate citrates and protonated/deprotonated triazolates, showing their synergistic effects. Furthermore, 1 exhibits a rectangular channel, showing preferential adsorption of O2 and CO2 over gases N2, H2, and CH4. [ABSTRACT FROM AUTHOR]

C37H36Cl2OSi, monoclinic P21/n (no. 14), a = 10.4363(14) Å, b = 17.128(2) Å, c = 17.875(3) Å, β = 90.934(2)°, V = 3194.8(8) Å3, Z = 4, Rgt(F) = 0.0491, wRref(F2) = 0.1449, T = 296.15 K. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to retrospectively review cases of intestinal anisakiasis diagnosed by CT over a 10-year period and to evaluate imaging findings associated with the disease. Methods: This retrospective study included 71 patients with clinical suspicion of intestinal anisakiasis in whom an abdominopelvic computed tomography (CT) was performed at a single institution between June 2011 and December 2021. To identify the cases, we used medical term search engines and the hospital's radiology case database. Clinical information was gathered from the medical records. A radiologist with five years of experience reviewed and analyzed the CT images to determine the characteristic findings of intestinal anisakiasis. Results: The study included 47 confirmed cases of intestinal anisakiasis. The mean age of the patients was 52 years (range 18–87 years), being more frequent in men than women (26:21). All patients reported ingestion of raw fish, most commonly anchovies in vinegar (30/47, 63,8%). Abdominal pain was the predominant symptom, accompanied by nausea, vomiting, and occasionally fever. The most common clinical suspicions were intestinal obstruction (14/47, 29,8%) and appendicitis (10/47, 21,3%), whereas intestinal anisakiasis was suspected in only 2 cases prior to imaging. CT showed thickening of the bowel wall with submucosal edema in all patients, predominantly involving the ileum (43/47, 91,5%), usually in a relatively long segment (mean of 17,5 cm, range 10–30 cm). Simultaneous involvement of multiple bowel segments was observed in 16 cases (34%). Intestinal obstruction with dilatation of proximal loops (33/47, 70,2%), ascites (45/47, 95,7%), and mesenteric fat striation (32/47, 68,1%) were also common findings. Conclusion: This study demonstrates the value of computed tomography in suggesting the diagnosis of intestinal anisakiasis, which often presents with nonspecific clinical manifestations. The characteristic CT findings that provide diagnostic clues are bowel wall thickening with submucosal edema, typically involving a long segment of the ileum, with signs of intestinal obstruction, ascites, and mesenteric fat striation. Simultaneous involvement of several intestinal segments (typically the gastric antrum and right colon) is an additional finding to be considered and may provide a diagnostic clue. [ABSTRACT FROM AUTHOR]

The mechanism for anaphylaxis following mRNA COVID-19 vaccination has been widely debated; understanding this serious adverse event is important for future vaccines of similar design. A mechanism proposed is type I hypersensitivity (i.e., IgE-mediated mast cell degranulation) to polyethylene glycol (PEG). Using an assay that, uniquely, had been previously assessed in patients with anaphylaxis to PEG, our objective was to compare anti-PEG IgE in serum from mRNA COVID-19 vaccine anaphylaxis case-patients and persons vaccinated without allergic reactions. Secondarily, we compared anti-PEG IgG and IgM to assess alternative mechanisms. Selected anaphylaxis case-patients reported to U.S. Vaccine Adverse Event Reporting System December 14, 2020–March 25, 2021 were invited to provide a serum sample. mRNA COVID-19 vaccine study participants with residual serum and no allergic reaction post-vaccination ("controls") were frequency matched to cases 3:1 on vaccine and dose number, sex and 10-year age category. Anti-PEG IgE was measured using a dual cytometric bead assay (DCBA). Anti-PEG IgG and IgM were measured using two different assays: DCBA and a PEGylated-polystyrene bead assay. Laboratorians were blinded to case/control status. All 20 case-patients were women; 17 had anaphylaxis after dose 1, 3 after dose 2. Thirteen (65 %) were hospitalized and 7 (35 %) were intubated. Time from vaccination to serum collection was longer for case-patients vs controls (post-dose 1: median 105 vs 21 days). Among Moderna recipients, anti-PEG IgE was detected in 1 of 10 (10 %) case-patients vs 8 of 30 (27 %) controls (p = 0.40); among Pfizer-BioNTech recipients, it was detected in 0 of 10 case-patients (0 %) vs 1 of 30 (3 %) controls (p >n 0.99). Anti-PEG IgE quantitative signals followed this same pattern. Neither anti-PEG IgG nor IgM was associated with case status with both assay formats. Our results support that anti-PEG IgE is not a predominant mechanism for anaphylaxis post-mRNA COVID-19 vaccination. [ABSTRACT FROM AUTHOR]

Micro visualization has become an important means of solving colloid and interface scientific problems in enhanced oil recovery. It can establish a relationship between a series of performance evaluations of an oil-water interface under macroscopic dimensions and the actual application effect in confined space, and more truly and reliably reflect the starting and migration behavior of crude oil or emulsion in rock pores. In this article, zwitterionic surfactant alkyl sulfobetaine (ASB) and anionic extended surfactant alkyl polyoxypropylene sulfate (A145) were employed as flooding surfactants. The macroscopic properties of the surfactant solutions, such as the oil-water interfacial tension (IFT), the interfacial dilational rheology and the viscosity of crude oil emulsions, have been measured. At the same time, we link these parameters with the oil displacement effect in several visual glass models and confirm the main factors affecting the migration ability of emulsions in micro-scale pores. The experimental results show that ASB reduces the IFT through mixed adsorption with crude oil fractions. The flat arrangement of the large hydrophilic group of ASB molecules enhances the interactions between the surfactant molecules on the oil-water interface. Compared with sulfate, betaine has higher interfacial membrane strength and emulsion viscosity. A145 has a strong ability to reduce the IFT against crude oil because of the larger size effect of the PO chains at the oil side of the interface. However, the membrane strength of A145 is moderate and the emulsion does not show a viscosity-increasing effect. During the displacement process, the deformation ability of the front emulsions or oil banks is the main controlling factor of the displacement efficiency, which is determined by the membrane strength and emulsion viscosity. The strong interfacial membrane strength and the high emulsion viscosity are not conducive to the migration of droplets in pore throats and may result in low displacement efficiency. [ABSTRACT FROM AUTHOR]

Optical lattices for coherently manipulating ultracold atoms demand high-power, low-noise, narrow-line-width, and continuous-wave lasers. Here, we report the implementation of a 30 W 532 nm low-noise laser by second harmonic generation from a 1064 nm fiber laser, which is capable to generate optical lattices for a quantum gas microscope of R b 87 atoms. The overall conversion efficiency is 59% at an input power of 51 W with a lithium triborate crystal coupled to a ring cavity. The relative intensity noise of the output laser is suppressed to −120 dBc/Hz in the range of 10 Hz–100 kHz with a high dynamic range of over 50 dB, which is suitable for long-term trapping and coherent manipulation of the quantum gases. [ABSTRACT FROM AUTHOR]

Control valves are indispensable fluid control units in various industrial systems, and adjustable ratio is a crucial performance indicator of these valves. It represents the ratio between the maximum and the minimum controllable flow of the valve. And adjustable ratio stands as a significant measure of control valve regulation capability. This paper presents a novel sleeve-type control valve with a combined valve core structure composed of an inner sleeve, an outer sleeve, and a valve plug. Throttle windows and orifices are machined onto both sleeves. A dual-layer sleeve movement mechanism is realized through a gear transmission structure, allowing rotation of the inner sleeve and vertical movement of the valve plug. This design can achieve higher adjustable ratios and regulation precision. The sleeve structure design include structural parameters of the inner sleeves, outer sleeves and the shape of the throttle windows. In this study, we get the flow rates at various openings by numerical simulations. And the adjustable ratio of the valve with orifice sleeves reaches up to 695:1. Furthermore, we validate the flow regulation accuracy and maximum adjustable ratio of the combined valve core control valve by experimental methods. This work has a relevance for the design and investigation of control valves under high-pressure differential and high-flow conditions. • This valve can realize the flow regulation with two degrees of freedom. • This study enhances the controllability range and precision of the control valve. • Reducing the sleeve wall thickness reduces the problem of valve regulation failure. • The design of the orifice sleeve significantly enhanced regulation of control valve. [ABSTRACT FROM AUTHOR]

Ferulic acid (FA) is a natural methylated phenolic acid which represents various bioactivities. Bioproduction of FA suffers from insufficient methyl donor supplement and inefficient hydroxylation. To overcome these hurdles, we first activate the S -adenosylmethionine (SAM) cycle in E. coli by using endogenous genes to supply sufficient methyl donor. Then, a small protein Fre is introduced into the pathway to efficiently regenerate FADH 2 for the hydroxylation. Remarkably, regeneration of these two cofactors dramatically promotes FA synthesis. Together with decreasing the byproducts formation and boosting precursor supply, the titer of FA reaches 5.09 g/L under fed-batch conditions, indicating a 20-fold improvement compared with the original producing E. coli strain. This work not only establishes a promising microbial platform for industrial level production of FA and its derivatives, but also highlights a convenient and effective strategy to enhance the biosynthesis of chemicals requiring methylation and FADH 2 -dependent hydroxylation. • Regeneration of cofactors promoted the efficiency of methylation and hydroxylation. • A highly specific HpaBC was screened for reducing the byproduct formation. • The engineered strain produced highest titer with 5.09 g/L FA in fed-batch fermenter. [ABSTRACT FROM AUTHOR]

Traumatic arterial injuries of the extremities are a rare but potentially fatal event. Computed tomography (CT) angiography of the extremities has become the technique of choice and can provide rapid accurate detection and characterization of vascular lesions. Vascular injuries can be classified in active hemorrhage, vasospasm, occlusion, post-traumatic arteriovenous fistula, pseudoaneurysm, and patterns of intimal injuries. The learning objectives of this pictorial essay are to review the normal arterial anatomy of the upper and lower limbs, describe the technique of CT angiography in vascular trauma of the extremities, describe and illustrate the CT-angiography findings of traumatic arterial injuries, and know the potential pitfalls when interpreting a CT-angiography of the extremities. [ABSTRACT FROM AUTHOR]

In this article, we propose an equivalent circuit theory-assisted deep learning approach to accelerate the design of metasurfaces. By combining the filter equivalent circuit theory and a sophisticated deep learning model, designers can achieve efficient metasurface designs. Compared with most existing metasurface generative design methods that rely on arbitrarily generated training dataset (TDS), the proposed method can adaptively produce highly relevant and low-noise training samples under the guidance of filter equivalent circuit theory, resulting in a significantly narrowed target solution space and improved model training efficiency. Furthermore, we select the variational autoencoder (VAE) as a generative model, which can compress the raw training samples into a lower-dimensional latent space where optimization methods, such as genetic algorithm, can be more efficiently executed to find the optimal design than a brute-force search. To verify the effectiveness of the proposed method, we apply it in the creation of three examples of frequency selective surfaces (FSSs), presenting wide-band, dual-band, and band-stop responses. Experimental results show that the proposed method can realize much faster and more stable convergence than deep learning design methods without domain knowledge. [ABSTRACT FROM AUTHOR]

In this work, a phase change material was synthesized from diphenyl methane diisocyanate and polyethylene glycol. Phase change material and polyester masterbatches were blended and granulated by a twin-screw extruder to make blend master batch. According to the result of FTIR, no transesterification reaction was found between phase change material and polyester. Process flow of melt spinning was determined by the results of DSC. The addition of phase change material did not have a big impact on spinnability. Thermo-regulated polyester fibers were prepared by melt spinning. The masterbatch of thermo-regulated polyester has a good fiber forming property. Thermo-regulated polyester fiber has a good storage phase change thermal function. Due to the addition of phase change material, the single fiber strength of polyester was decreased and the elongation at break was improved slightly. The thermo-regulated polyester and polyester had the essentially the same moisture regain and hand feel. [ABSTRACT FROM AUTHOR]

A new gate driver with metal oxide thin‐film transistors (MO‐TFTs) has been presented for micro‐light‐emitting diode (Micro‐LED) display. The proposed gate driver employing linearly decreasing sweep signal generated module could realize the line‐by‐line pulse width modulation (PWM) driving method, which is valuable for application in high‐resolution Micro‐LED display compared with the conventional driving method employing global sweep signal. A simple Micro‐LED pixel circuit including an inverter module driven by the analog PWM method is employed to demonstrate the feasibility of the proposed gate driver. A 10 × 10 green Micro‐LED display array has been fabricated with MO‐TFTs backplane technology. It is shown that a 10‐μs width pulse and linearly scanning sweep signal can be successfully output. Consequently, the pixel circuit array can be driven properly under analog line‐by‐line PWM driving method. [ABSTRACT FROM AUTHOR]

Studies have demonstrated that small interfering RNA (siRNA) targeting YKL‐40 (siYKL‐40) inhibits the proliferation, migration, invasion, and induces antiapoptotic abilities of endometrial cancer (EC) HEC‐1A cells. However, its effect on angiogenesis is unclear. The present study aimed to investigate the role of YKL‐40 in endometrial cancer and the related molecular mechanisms. YKL‐40 was knocked down by transfection with siYKL‐40 and the effects on angiogenesis, cell viability, and signaling pathways were investigated. The results showed that siYKL‐40 inhibited VEGFA levels and tube formation in endothelial cells. Additionally, inhibition of YKL‐40 decreased the expression levels of vascular endothelial growth factor (VEGF), phosphorylated vascular endothelial growth factor receptor 2 (pVEGFR2), and phosphorylated extracellular signal‐regulated kinases 1 and 2 (pERK1/2). Furthermore, a nude mice xenograft model of EC showed that siYKL‐40 inhibited tumor growth. Inhibition of YKL‐40 led to suppression of angiogenesis and reduction of microvessel density through VEGF/VEGFR2 and ERK1/2 signaling in endometrial cancer cells. Taken together, this study demonstrated novel molecular mechanisms for role of YKL‐40 in EC. [ABSTRACT FROM AUTHOR]

Herein, a highly regioselective alkylation of propargylic carbonates for trisubstituted allenes with alkyl 1,4-dihydropyridine derivatives (1,4-DHPs) is developed via a photoredox/nickel dual-catalyzed process, which represents the first direct approach to access alkylated allene products without alkyl organometallic reagents. This method features a broad substrate scope and mild conditions. A hypothetical mechanism with an alkyl radical and an allenyl Ni(III) species is proposed. Benzylation products were also obtained to be the complement building blocks for the potential synthesis of pharmaceuticals. [ABSTRACT FROM AUTHOR]

This paper studies the stochastic stability of opinion formation systems under both non‐time delay and time delay. Individuals whose opinions are affected by multiplicative noise are considered. Subsequently, a stochastic opinion formation model on coopetitive social networks which take both multiplicative noise and time delay into consideration and give the analysis of stochastic stability is introduced. When the continuous‐time system of opinion evolution is disturbed by stochastic multiplicative noise, the stability of the stochastic opinion formation system is dependent on the noise intensity and the topology structure. When the continuous‐time system of opinion dynamic is disturbed by time delay and multiplicative noise, the bounds of the noise intensity and time delay ensure the stochastic stability of the above system. Finally, numerical simulations are given to illustrate the above theoretical results. [ABSTRACT FROM AUTHOR]

The phenomenon of nomophobia, defined as the anxiety experienced when a person is without their mobile phone or is unable to use it, has been identified as having serious negative effects on individuals, particularly students. Previous research has explored the relationship between personality traits and nomophobia, but the findings have been inconclusive. The main objective of this study was to classify personality types through latent class analysis and explore the relationship between these personality types and nomophobia. The Chinese version of the Nomophobia Scale and the Chinese brief version of the Big Five Personality Inventory were used in this study to survey 1906 Chinese college students. The results indicated that (1) a four‐class model provided the best fit and categorized the personality traits as the overcontrolled class, resilient class, moderate class, and vulnerable class; (2) significant differences were observed between the four personality types and nomophobia, with overcontrolled and resilient personality types consistently scoring significantly lower than moderate and vulnerable personality types. Our finding highlights the key feature of the study. [ABSTRACT FROM AUTHOR]

Neutralizing antibodies to the SARS CoV-2 spike proteins have been issued Emergency Use Authorizations and are a likely mechanism of vaccines to prevent COVID-19. However, benefit of treatment with monoclonal antibodies has only been observed in clinical trials in outpatients with mild to moderate COVID-19 but not in patients who are hospitalized and/or have advanced disease. To address this observation, we evaluated the timing of anti SARS-CoV-2 antibody production in hospitalized patients with the use of a highly sensitive multiplexed bead-based immunoassay allowing for early detection of antibodies to SARS-CoV-2. We found significantly lower levels of antibodies to the SARS-CoV-2 spike protein in the first week after symptom onset in patients who expired as compared to patients who were discharged. We also developed a model to characterize the relationship between each patient's individual antibody level trajectory and eventual COVID 19 outcome which can be adapted into a prediction model with more data. Author summary: We evaluated antibodies to SARS-CoV-2 over time in patients that were hospitalized with COVID 19. Early detection of Anti-SARS-CoV-2 antibodies was associated with survival in patients hospitalized with COVID 19. Early antibody levels predicted outcome in our study. This result is consistent with the benefit of therapeutic antibodies early in the course of COVID 19 disease. With additional study, early antibody levels may be helpful in deciding on appropriate therapies. [ABSTRACT FROM AUTHOR]

Cancer-associated fibroblasts cells (CAFs) confer a rapid growth and metastasis ability of endometrial cancer (EC) via exosomes-mediated cellular communication. Long non-coding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) drives the malignant phenotypes of EC cells. However, the role of exosomal NEAT1 from CAFs in EC progression remains ambiguous, which needs to be investigated. In our study, NEAT1 and YKL-40 were up-regulated, while miR-26a/b-5p was down-regulated in EC tissues. Moreover, NEAT1 expression was increased in CAF-exosomes compared with that in NF-exosomes. In addition, the exosomal NEAT1 derived from CAFs could transfer to EC cells and promote YKL-40 expression. Further exploration showed that exosomal NEAT1 enhanced YKL-40 expression via regulating miR-26a/b-5p-STAT3 axis in EC cells. More importantly, exosomal NEAT1 accelerated in vivo tumor growth via miR-26a/b-5p-STAT3-YKL-40 axis. Taken together, our study reveals that exosomal NEAT1 from CAFs contributes to EC progression via miR-26a/b-5p-mediated STAT3/YKL-40 pathway, which indicates the therapeutic potential of exosomal NEAT1 for treating EC. [Display omitted] [ABSTRACT FROM AUTHOR]

We conducted a systematic evaluation of lung inflammation indued by repeated intranasal exposure (for 10 consecutive days) to a human aeroallergen, house dust mite (HDM) in BALB/c mice. Peak influx of neutrophils, monocytes/lymphocytes, and eosinophils was observed in bronchoalveolar lavage (BAL) on days 1, 7 and 11, respectively, and normalized to baseline by day 21. Peak elevations of Th2, myeloid‐derived cytokines/chemokines and serum IgE were seen both in BAL and lung tissue homogenates between days 7 and 11, and declined thereafter; however, IL‐33 levels remained elevated from day 7 to day 21. Airway hyperreactivity to inhaled methacholine was significantly increased by day 11 and decreased to baseline by day 21. The lung tissue showed perivascular and peribronchial cuffing, epithelial hypertrophy and hyperplasia and goblet cell formation in airways by day 11, and resolution by day 21. Levels of soluble collagen and tissue inhibitors of metalloproteinases (TIMP) also increased reflecting tissue remodeling in the lung. Microarray analysis demonstrated a significant time‐dependent up‐regulation of several genes including IL‐33, CLCA3, CCL17, CD4, CD10, CD27, IL‐13, Foxa3, IL‐4, IL‐10, and CD19, in BAL cells as well as the lung. Pre‐treatment of HDM challenged mice with CCL17 and IL‐13 antibodies reduced BAL cellularity, airway hyper‐responsiveness (AHR), and histopathological changes. Notably, anti‐IL‐13, but not anti‐CCL17 monoclonal antibodies (mAbs) reduced BAL neutrophilia while both mAbs attenuated eosinophilia. These results suggest that CCL17 has an overlapping, yet distinct profile versus IL‐13 in the HDM model of pulmonary inflammation and potential for CCL17‐based therapeutics in treating Th2 inflammation. [ABSTRACT FROM AUTHOR]

The skin, the primary barrier of the body, is inevitably broken. However, the development of materials that facilitate wound healing with sustained antimicrobial, hemostatic, and biocompatible properties remains a formidable challenge. In this article, we prepared a photopolymerizable composite hydrogel consisting of a hydrogel matrix, a hemostatic/antibacterial agent, and a photothermal therapy agent. The photopolymerizable hydrogel matrix was prepared by grafting the photoinitiator and polymerizable active monomer onto the chitosan chain segment, which exhibits excellent biocompatibility. Furthermore, linalool is adsorbed on the surface of halloysite nanotubes (HNTs) to form a hemostatic and antibacterial. Meanwhile, dopamine is employed as a coating material for hollow glass microsphere (HGM), which enables them to function as photothermal therapy agents. Upon exposure to near-infrared radiation, the PHA hydrogel releases linalool molecules from the surface of the HNTs, which diffuse into the hydrogel matrix, resulting in a sustained antimicrobial effect. At the same time, rapid curing of the photopolymerizable hydrogel under UV light forms a physical barrier that synergistically enhances the hemostatic properties of the HNTs. From the above, the results pave the way to develop a potential hemostatic antimicrobial dressing for clinical use in wound healing. [ABSTRACT FROM AUTHOR]

Accumulation of senescent cells in organs and tissues is a hallmark of aging and known to contribute to age-related diseases. Although aging-associated immune dysfunction, or immunosenescence, is known to contribute to this process, the underlying mechanism remains elusive. Here, we report that type 2 cytokine signaling deficiency accelerated aging and, conversely, that the interleukin-4 (IL-4)-STAT6 pathway protected macrophages from senescence. Mechanistically, activated STAT6 promoted the expression of genes involved in DNA repair both via homologous recombination and Fanconi anemia pathways. Conversely, STAT6 deficiency induced release of nuclear DNA into the cytoplasm to promote tissue inflammation and organismal aging. Importantly, we demonstrate that IL-4 treatment prevented macrophage senescence and improved the health span of aged mice to an extent comparable to senolytic treatment, with further additive effects when combined. Together, our findings support that type 2 cytokine signaling protects macrophages from immunosenescence and thus hold therapeutic potential for improving healthy aging. [Display omitted] • Deficiency of IL-4 signaling accelerates organismal aging • Loss of Stat6 induces macrophage senescence • The IL-4-STAT6 axis regulates DNA repair in macrophages • IL-4 treatment improves health span of aged mice Aging induces cellular senescence of immune cells, yet the underlying mechanism is poorly understood. Here, Zhou et al. reveal that type 2 cytokine signaling protects macrophages from senescence by directly sustaining DNA repair. They further show that IL-4 treatment alleviates cellular senescence and improves health span of aged mice. [ABSTRACT FROM AUTHOR]

Herein, a highly regioselective propargylic benzylation with propargylic carbonates and benzyl 1,4-dihydropyridine derivatives was developed via a photoredox/palladium dual-catalyzed process, which represents a novel catalytic model for non-terminal propargylic functionalization. The reaction showed excellent regioselectivity and functional group compatibility. A radical coupling mechanism between the propargylic radical and benzyl radical was proposed. [ABSTRACT FROM AUTHOR]

Glutamine gets transformed to 2-hydroxy-5-oxoproline with NH4VO3 in a neutral solution as a product of 2,2′-bipyridine oxidovanadium(V) 2-hydroxy-5-oxoproline [VV2O3(hop)2(bpy)2]·7H2O [1, H2hop = 2-hydroxy-5-oxoproline] with yields of 65.6%. Similarly, histidine and arginine are converted into the corresponding α-hydroxycarboxylates as 2,2′-bipyridine oxidovanadium(IV) 3-(1H-imidazolyl-5-yl)-2-hydroxyacrylate [VIV2O2(imha)2(bpy)2]·bpy [2, H2imha = 3-(1H-imidazolyl-5-yl)-2-hydroxyacrylic acid] and guanidinium oxidovanadium(V) 1-(aminoiminomethyl)-2-hydroxyproline (CN3H6)[VVO2(Haimhp)2]·2H2O [3, H2aimhp = 1-(aminoiminomethyl)-2-hydroxyproline] with V2O5 in low yields respectively, where an aggregate of oxidovanadium(V) arginine (H2arg)n(VVO3)n·½nH2O (4, Harg = arginine) has been isolated preferentially in an initial experiment for 3. α-Hydroxycarboxylates chelate bidentately with vanadium via α-alkoxy and α-carboxy groups in 1–3, as observed from structural analyses. Their racemizations have been observed after the conversions. There is no coordination in 4 based on solid-state 13C NMR spectra, and only strong hydrogen bonds exist in the anion chains (VVO3)− and protonated arginines. 1 and 4 were fully characterized by elemental analysis, UV–vis, IR and solid-state 13C NMR spectroscopies, TG and X-ray structural analyses, and theoretical bond valence calculations (BVS). The conversions of glutamine, histidine and arginine occur spontaneously in a solution under ambient conditions. [ABSTRACT FROM AUTHOR]

This work is mainly focused on developing a self-heating composite fabric using the PVF and PPP. Prepare a new functional composite self-heating fabric through core spun method based on the synergy of hygroscopic heating principle and the characteristics of piezoelectricity of tourmaline. PVF with good hygroscopicity and PPP with piezoelectric effect were blended to produce fabrics with continuous heating function. Spandex fiber filament was set as a core to introduce elasticity, and the PVF and PPP were set as a sheath. In order to test the heating insulation properties of the fabric better, an athlete volunteer to be test foe the self-heating properties of fabrics during exercise. The heart rate was used to characterize the athlete's exercise intensity. The fever effect was not particularly obvious when the exercise intensity was low because the human body sweats less, but with the increase of exercise intensity, the heating effect increases obviously. And when the exercise intensity continues to increase, the body releases a lot of heat, which made the heat released by the fabric becomes less obvious. Therefore, the functional composite self-heating fabric is promising materials in sports injury protection of athletes applications. [ABSTRACT FROM AUTHOR]

Background: With the ageing of China's population, the incidence and mortality of coronary atherosclerotic heart disease (CAD) is increasing year by year, which brings a heavy burden to the family and society [1]. We aimed to analyse the strategy of coronary artery bypass grafting (CABG) in the right coronary artery and to compare the haemodynamic characteristics of the sequential grafts with those of single grafts and to observe the patency rate of those grafts for 1 week after the operation.Methods: A total of 242 patients (178 men, mean age 62.6 ± 8.8 years) underwent right coronary artery bypass grafting in our hospital from October 2016 to January 2019. The blood flow (Q, ml/min), pulsatility index (PI) and related parameters of the grafts were measured and recorded by TTFM during the CABG. The patency of the grafts was evaluated by coronary computed tomography (CT) for 1 week after the operation.Results: The most common material used for the graft in the right coronary system of CABG is the greater saphenous vein (92.3%), followed by the radial artery (5.5%) and the internal mammary artery (1.9%). The highest frequency target of the right coronary artery is the posterior descending artery (PDA) (47.6%), followed by the right main coronary artery (RCA) (29.1%) and the posterior branch of the left ventricle (PL) (23.3%). The proportion of single grafts was the highest for the right coronary artery in CABG (178 cases, 67.9%), followed by a graft of the PDA-PL (42 cases, 16.0%) and other sequential grafts among the different coronary artery systems (including the system of the left anterior descending artery (LAD) and the left circumflex (LCX)). Whether there were sequential grafts of the PDA-PL or other sequential grafts among the different systems of the coronary artery, the instantaneous flow of a group of sequential grafts was higher than that of a single graft, and the difference had statistical significance (P < 0.01). However, there were no significant differences in the flow between the groups of sequential grafts (P = 0.410). Diastolic flow (DF) in the group of sequential grafts of the right coronary system was better than that in the non-sequential group (P < 0.001), and the difference had statistical significance. There was no significant difference between the DF of the groups of the other system of sequential grafts and that of the right coronary sequential grafts. Coronary artery CT suggested that there were 11 cases of poorly developing grafts or stenosis and occlusion a week after the operation, and those phenomenon mainly occurred in the group with a single graft. There was only one case that was occluded in the group of other systems of sequential grafts, and statistically significant differences existed between the two groups (P < 0.01).Conclusions: In our centre, the most common form of CABG in the right coronary artery system is a non-sequential vein bridge to the PDA. Whether there are sequential grafts of the PDA-PL or other sequential grafts among the different coronary artery systems, the instantaneous flow of a group of sequential grafts is higher than that of a single graft. DF in the group of sequential grafts of the right coronary system was better than that in the non-sequential group. [ABSTRACT FROM AUTHOR]

The article proposes a partial flaring gate pier (FGP) scheme to intensify the energy dissipation inside a conventional stilling basin. Topics discussed include secondary hydraulic jump, vertical vortex, and deep tailwater. Also mentioned are the volume of fluid (VOF) method for the computation of the free space, numerical model implementation, and boundary conditions and initial conditions.

A filtering magnetoelectronic dipole antenna (MEDA) with quasi-elliptic gain response and wide operating band is investigated. Different from the conventional MEDA, the antenna studied here is fed by fork-shaped microstrip line aperture-coupled excitation. The intrinsic radiation null of the MEDA at the lower passband edge is utilized, and a mathematical model is first put forward to demonstrate its working mechanism. Four driven stubs connected to the shorted walls of MEDA are used to excite the planar dipole arms. The parasitic inductor and the coupling capacitor introduced by driven stubs form an equivalent low-pass filter network, leading to a radiation null at higher frequency. Furthermore, a third radiation null is generated by introducing two quarter-wavelength U-shaped shorted stubs to improve the out-of-band suppression. Besides, due to the introduction of multiple coupling structure, including the fork-shaped microstrip line coupling slot and driven stubs, a wide operating band can be realized while maintaining a low profile of 0.15 wavelength. The experimental results show that an impedance bandwidth of 53.5% (2.95–5.1 GHz) is achieved and an out-of-band suppression level higher than 17.9 dB is obtained. What is more, an average gain of 8 dBi and good radiation patterns are realized over the whole operating band. [ABSTRACT FROM AUTHOR]

The gut microbiota that inhabit our gastrointestinal tract are well known to play an important role in maintaining human health in many aspects, including facilitating the digestion and absorption of nutrients, protecting against pathogens and regulating immune system. Gut microbiota dysbiosis is associated with a lot of diseases, such as inflammatory bowel disease, allergy, obesity, cardiovascular and neurodegenerative diseases and cancers. With the increasing knowledge of the microbiome, utilization of probiotic bacteria in modulating gut microbiota to prevent and treat a large number of disorders and diseases has gained much interest. In recent years, aided by the continuous development of tools and techniques, engineering probiotic microbes with desired characteristics and functionalities to benefit human health has made significant progress. In this paper, we summarize the recent advances in design and construction of probiotics as living diagnostics and therapeutics for probing and treating a series of diseases including metabolic disorders, inflammation and pathogenic bacteria infections. We also discuss the current challenges and future perspectives in expanding the application of probiotics for disease treatment and detection. We intend to provide insights and ideas for engineering of probiotics to better serve disease therapy and human health. [ABSTRACT FROM AUTHOR]

The electronic structures of FeFe-cofactors (FeFe-cos) in resting and turnover states, together with their PN clusters from iron-only nitrogenases, have been calculated using the bond valence method, and their crystallographic data were reported recently and deposited in the Protein Data Bank (PDB codes: 8BOQ and 8OIE). The calculated results have also been compared with those of their homologous Mo- and V-nitrogenases. For FeFe-cos in the resting state, Fe1/2/4/5/6/7/8 atoms are prone to Fe3+, while the Fe3 atom shows different degrees of mixed valences. The results support that the Fe8 atom at the terminal positions of FeFe-cos possesses the same oxidation states as the Mo3+/V3+ atoms of FeMo-/FeV-cos. In the turnover state, the overall oxidation state of FeFe-co is slightly reduced than those in the resting species, and its electronic configuration is rearranged after the substitution of S2B with OH, compatible with those found in CO-bound FeV-co. Moreover, the calculations give the formal oxidation states of 6Fe2+–2Fe3+ for the electronic structures of PN clusters in Fe-nitrogenases. By the comparison of Mo-, V- and Fe-nitrogenases, the overall oxidation levels of 7Fe atoms (Fe1–Fe7) for both FeFe- and FeMo-cos in resting states are found to be higher than that of FeV-co. For the PN clusters in MoFe-, VFe- and FeFe-proteins, they all exhibit a strong reductive character. [ABSTRACT FROM AUTHOR]

Due to great velocity gradients among the outgoing flow, it is much common to form large-scale reverse flow with oblique movements outside the conventional separated stilling basin. Aimed at above problems, this paper proposes to remove the longitudinal splitter wall and then physically and numerically investigate the corresponding influence upon the compound stilling basin. The standard k-ε, renormalization group k-ε, realizable k-ε, and large eddy simulation turbulence models are all employed to reveal downstream three-dimensional flow field. Experimental validation of numerical results shows that the renormalization group k-ε turbulence model is the most successful in predicting the flow field among the four models. Both methods prove that the removed splitter wall exerts great impact upon downstream stilling basin. In view of the removed splitter wall, discharging inflow would greatly diffuse to form a typical three-dimensional (3D) hydraulic jump with large-scale reverse flow. High energy dissipation region and high turbulent kinetic energy region are both moved upstream. Thus, the velocity decay among the discharging flow in the compound stilling basin is significantly enhanced. Compared to the separated stilling basin, the maximum velocity and average velocity of the outgoing flow, respectively, decrease more than 30%, and 20% in the compound stilling basin. Additionally, the velocity gradients between the left and the right outgoing flow reduce by over 65% with turbulent kinetic energy gradients almost down to zero. The outgoing flow from the compound stilling basin becomes much uniform with the phenomenon of obliquely moving flow totally eliminated. [ABSTRACT FROM AUTHOR]

In order to develop a flame retardant using the phosphazene derivative of a natural polymer, hexachlorocyclotriphosphazene and collagen were used as the raw materials to synthesize collagencoclotriphosphazene. The Fourier transform infrared results indicate that flame retardant collagencoclotriphosphazene(CGCP) was successfully synthesized. Thermal properties of CGCP were evaluated using thermogravimetry. The thermal analysis shows that the introduction of phosphazene into collagen lowered the primary decomposition temperature, increased the decomposition rate, and caused less weight loss. The viscose fibers blended by CGCP were prepared by the wet spinning method, and the properties of the fiber were investigated. Limiting oxygen index of the flame-retardant fiber containing 12% CGCP was 28.3%, which increased greatly comparing to the fiber sample without CGCP and just decreased slightly to 27.6% after 30 washing cycles. The thermal analysis shows that the introduction of CGCP increased the decomposition rate of viscose fiber at a lower temperature, and caused less weight loss. After burning, the scanning electron microscopy image showed an inflated carbonized coat on the fiber surface. The effect of CGCP on the mechanical properties of the fibers was insignificant. CGCP was compatible with cellulose, and the flame retardancy of the viscose fiber was significantly improved. Due to the introduction of CGCP, moisture regain of the fiber is a little higher than that of viscose fiber. [ABSTRACT FROM AUTHOR]

The adipic acid glycidyl methacrylate (AA-GMA) containing double bond of carbon and hydroxyl as an ultraviolet-polyurethane dual-curing oligomer was prepared as a precursor to resin for three-dimensional (3D) printing. A dual-curing resin for 3D printing was formulated from the AA-GMA, PHDI (hexamethylene diisocyanate-based polyisocyanates, mainly trimer) and other reagents. The dual-curing oligomer AA-GMA was synthesized by the epoxide ring-opening reaction with dicarboxylic acid and the molecular structure of which was characterized by FTIR and 1H NMR analyses. AA-GMA has the double bond which could be cured via ultraviolet irradiation in the 3D printing process, and the hydroxyl could be cured by PU curing agent PHDI at the thermal post-curing process. The PHDI was not only employed as a diluent in the 3D printing process, but also acted as a reactant for post-curing. Compared to the traditional single-curing resin, this dual-curing resin could provide products with increased crosslinking density, flexibility and reduced volumetric shrinkage rate. The tensile strength of dual-curing sample was improved to 64 MPa after adding 20 wt% PHDI, which showed 18% boost compared to the sample without the PHDI. For the sample with a content of 30 wt% PHDI, the glass transition temperature (Tg) was about 121 °C, presenting 35 °C higher than that of the blank sample. [ABSTRACT FROM AUTHOR]

Abstract The adsorption and wettability of benzyl substituted alkyl carboxylbetaine (BCB) and alkyl sulfobetaine (BSB) at polymethylmethacrylate (PMMA) surfaces have been studied by contact angle measurements and the adsorption parameters such as adhesional tension, adsorption amount, work of adhesion and PMMA-liquid interfacial tension (γ SL) have been calculated. The results show that the values of contact angle of betaines keep constant before CMC, which can be explained well by the compensation effect of the decrease of surface tension and increase of γ SL with an increase of bulk concentration. However, only the contact angle of BCB solution begins to decline when the concentration is far higher than CMC, indicating the re-adsorption. Both the hydrophilic head and benzyl of BCB molecules interact with PMMA surface, which decreases adsorption amount but improves ability of hydrophobic modification for PMMA. On the other hand, the benzyl may trend to stretch towards aqueous for BSB, instead of interacting with PMMA, because of the steric effect of larger hydrophilic head of BSB. The unique arrangement of BSB molecules at PMMA surface makes it difficult to re-adsorb onto monolayer at higher bulk concentration. Highlights • The contact angle of BCB and BSB keep almost a constant value before CMC. • Both the hydrophilic head and benzyl of BCB molecules interact with PMMA surface. • The re-adsorption of BCB at PMMA above CMC leads to a decrease of contact angle. • The benzyl may trend to stretch towards aqueous for BSB, instead of interacting with PMMA. • The unique arrangement of BSB molecules at PMMA surface limits the re-adsorption above CMC. [ABSTRACT FROM AUTHOR]

Harmonia axyridis (Pallas) and Propylea japonica (Thunberg) (both Coleoptera: Coccinellidae) are two common aphidophagous predators that overlap in their natural niche; therefore, interactions between these two predator species could affect their overall prey consumption. The consequences of intraguild interactions on the foraging efficiency of the two coccinellid species were investigated by evaluating the functional responses of single beetles and intra‐ and interspecific combinations to densities of the spirea aphid, Aphis citricola van der Goot (Hemiptera: Aphididae), on apple seedlings, during 2 and 12 h under laboratory conditions. A type II functional response was observed in all the bioassays. Solitary H. axyridis consumed significantly more aphids than single P. japonica in both exposure periods. However, at intermediate prey densities the prey consumption of P. japonica was slightly greater than that of H. axyridis. The 95% confidence intervals of the functional response curves of conspecific and heterospecific pairs overlapped at 2 h. In contrast, conspecific pairs of H. axyridis showed a higher functional response curve at 12 h compared to a combination of H. axyridis and P. japonica. Prey's predation risk reduction was only detected for paired H. axyridis and mixed predators compared to their estimated functional responses at the 2‐h foraging period. By comparing functional responses between intraguild predatory lady beetle combinations, we could further predict the potential ecosystem service provided by these natural enemies. Comparison of functional responses between various combinations of predators is a valuable approach to predict and assess multiple predator impact on their shared prey populations. Functional responses of single and intra‐ and interspecific combinations of Harmonia axyridis and Propylea japonica (Coleoptera: Coccinellidae) to densities of Aphis citricola (Hemiptera: Aphididae) on apple seedlings were evaluated at two exposure times under laboratory conditions. Our results indicated that interactions between the predatory beetles can alter their functional responses, and thus their overall prey consumption. [ABSTRACT FROM AUTHOR]

Abstract Chondroitinase ABC I (ChSase ABC I), as a polysaccharide lyase, can catalyze high molecular weight chondroitin sulfate (CS) to low molecular weight glycosaminoglycan which are easier to be absorbed and utilized by organisms. In this study, to enhance the production of ChSase ABC I and avoid the negative influence of tags on its catalytic efficiency, we employed molecular chaperones to co-express with ChSase ABC I. Firstly, different molecular chaperones and their combinations were screened and GroES exhibited the best positive effect. Consecutively, fermentation conditions were optimized to further improve the production. As a result, the production of ChSase ABC I was increased to 4640.44 ± 896.26 IU/g wet weight, a 2.15-fold higher value when compared with that of control in the same fermentation conditions. After that, to testify the influence of GroES on characterization of ChSase ABC I, the optimal pH and temperature, and kinetic parameters were confirmed. The affinity to substrate of ChSase ABC I with GroES assist was increased 7 folds as compared to the native ChSase ABC I, and ChSase ABC I with GroES co-expression still has high catalytic activity. This work not only presents to date the first achievement of ChSase ABC I high-level production with molecular chaperone co-expression, but also serves as a potential basis for its industrial application. Highlights • GroES was screened as the best molecular chaperone. • The activity of ChSase ABC I increased to 4640.44 IU/g wet weight. • GroES had no obvious influence on catalytic efficiency of ChSase ABC I. • This work served as a basis for the industrial application of ChSase ABC I. [ABSTRACT FROM AUTHOR]

• Betaine can mixed adsorb with crude oil fractions to produce ultralow IFT. • Active components in crude oil will further enhance the oil–water interfacial film strength. • High film strength has a certain contribution to sweep efficiency, but brings obstacle to emulsions movement. • Smaller oil droplets with higher film strength can improve the startup efficiency and smooth migration of pore crude oil. Betaine, an emerging surfactant for enhanced oil recovery (EOR), has garnered increased attention and recognition. This study focuses on linear alkylbenzene sulfonate betaine (ASB) as the research subject, and different crude oils were utilized to prepare two types of oil–water formulations with high interfacial film strengths but differed interfacial tensions. The interfacial properties were characterized and explored using interfacial dilational rheology, droplet squeeze coalescence, interfacial tension, emulsification, microscopic visualization, and other measuring methods. The actual emphasis in interfacial film properties of betaine as a standalone chemical EOR formulation was clarified. The results indicated that betaine had generally high interfacial film strength with selected crude oils, at this time, the slight difference in film strength had a negligible effect on enhancing the recovery. The main contributing factor was the difference in interfacial tension between the oil and water. Ultra-low interfacial tension could increase the stripping efficiency of oil in pore, reduce the energy required to emulsification or oil droplets initiation, and ensure that droplets were displaced and collected in smaller sizes, thereby avoiding large oil droplets trapped in the pore throat and unable to pass. Making good use of the advantages of improving sweep efficiency brought by high interfacial film strength, at the same time giving the system ultra-low oil–water interfacial tension, ensuring the start-up and migration of porous crude oil, is the core construction principle of betaine surfactant applied to EOR. [ABSTRACT FROM AUTHOR]

Bladder cancer is the 10th most prevalent cancer worldwide, with men having a lifetime risk of 1.1% and women 27%. The molecular mechanisms underlying the progression of bladder cancer from non-muscle invasive to muscle invasive are not well understood. This study used high-throughput RNA sequencing to identify differential gene expressions between the two types of bladder cancer. The researchers found that the upregulation of the PHB gene in muscle invasive bladder cancer tissues was associated with increased binding of the NADSYN1 mRNA to the PHB protein. Further experiments demonstrated that the interaction between PHB and NADSYN1 promoted bladder cancer progression. The study also identified Snai2 as a transcription factor that regulates the expression of NADSYN1, and its inhibition was associated with improved survival in bladder cancer patients. [Extracted from the article]

C41H42O2Si, monoclinic, P21/n (no. 14), a = 14.1100(17) Å, b = 15.8352(19) Å, c = 16.644(2) Å, β = 110.659(2)°, V = 3479.7(7) Å3, Z = 4, Rgt(F) = 0.0540, wRref(F2) = 0.1633, T = 296.15 K. [ABSTRACT FROM AUTHOR]

The effects of prey distribution and digestion on the functional response of an invertebrate predator Harmonia axyridis (Pallas) to varying densities of Aphis citricola (van der Goot) were investigated. Experiments were conducted in petri dish and wind tunnels with multiple plants to present conditions in which the predator could behave more naturally. To discriminate if the functional response of H. axyridis is digestion or handling limited, numbers of aphids consumed were measured at five time-points during a 24 h period in all assays. In the wind tunnel, aphid consumption was measured with two types of prey distributions (aggregate and uniform). Type 2 functional responses were observed in petri dish and three wind tunnel assays with aphid uniformly distributed (6, 12 and 24 h). Based on the Akaike Information Criterion (AIC) value, type 1 response was most appropriate for two assays (1 and 2 h) with aphid uniformly distributed and all assays with aphid aggregate in wind tunnels. There was a significant effect of aphid distribution and its interactions with experiment duration and prey density on the number of aphids consumed in wind tunnel. The functional responses between uniform and aggregate treatments were mostly overlapped except when prey densities were above 90. This indicates that prey distribution could affect H. axyridis foraging under relative high prey densities. Prey risk raised as the increase of experiment duration for all treatments, while attack rates and handling times differed significantly among the assays with different experimental lengths, thus digestion process could limit predation process of H. axyridis . Our results indicate that prey distribution and predator digestion could alter predator-prey interactions and thus the capacity of this generalist predator to suppress aphids. [ABSTRACT FROM AUTHOR]

Measurements of the surface dilational rheological properties have been carried out for aqueous solutions of four zwitterionic surfactants, hexadecanol glycidyl ether glycine betaine (C 16 PB), guerbet alcohol hexadecyl glycidyl ether glycine betaine (C 16 GPB), hexadecanol polyoxyethylene(3) glycidyl ether glycine betaine (C 16 (EO) 3 PB) and guerbet alcohol hexadecyl polyoxyethylene(3) glycidyl ether glycine betaine (C 16 G(EO) 3 PB), using the oscillating bubble method. The influences of surface ageing time, surface pressure, dilational frequency and bulk concentration on surface rheological properties have been expounded. It is found that the whole hydrophilic part of betaine molecule inclines to flat on the surface when betaine adsorbs, which will lead to higher dilational modulus. The nature of adsorption film is determined by in-surface processes, such as the variation of orientation of hydrophilic group. The branched hydrophobic alkyl chains of betaine molecules improve the intermolecular interactions, not only results in higher moduli, but causes a maximum in dynamic elastic modulus at high concentration. This indicates that the strength of surface film is strongly related to molecular arrangement, not simply determined by the surface molecule concentration. When ethylene oxide groups are incorporated in the hydrophobic group, the enhancement of steric hindrance will decrease both elastic modulus and viscous modulus. [ABSTRACT FROM AUTHOR]

A concise and facile approach for the construction of 2-hydroxy-2-substituted indol-3-ones was developed through an oxidative cyclization of 2-aminophenyl-1,3-dione. Using CAN and TEMPO as oxidants, C2-quaternary 2-hydroxy-indolin-3-ones were efficiently installed in moderate to excellent yields (up to 99%). Moreover, this developed protocol was further applied to synthetic studies towards natural product matemone by starting from readily available 2-amino-4-bromobenzoic acid, and the precursor for matemone was efficiently installed. [ABSTRACT FROM AUTHOR]

The dynamics of evaporating sessile droplets on hydrophilic or hydrophobic surfaces is widely studied, and many models for these processes have been developed based on experimental evidence. However, few research has been explored on the evaporation of sessile droplets of surfactant or pesticide solutions on target crop leaves. Thus, in this paper the impact of surfactant concentrations on contact angle, contact diameter, droplet height, and evolution of the droplets’ evaporative volume on rice leaf surfaces have been investigated. The results indicate that the evaporation kinetics of surfactant droplets on rice leaves were influenced by both the surfactant concentrations and the hydrophobicity of rice leaf surfaces. When the surfactant concentration is lower than the surfactant CMC (critical micelle concentration), the droplet evaporation time is much longer than that of the high surfactant concentration. This is due to the longer existence time of a narrow wedge region under the lower surfactant concentration, and such narrow wedge region further restricts the droplet evaporation. Besides, our experimental data are shown to roughly collapse onto theoretical curves based on the model presented by Popov. This study could supply theoretical data on the evaporation of the adjuvant or pesticide droplets for practical applications in agriculture. [ABSTRACT FROM AUTHOR]

This contribution is concerned with the imidazolium-based ionic liquid surfactant being considered potential amphiphilic molecules. The interfacial dilational rheology of solutions of globular proteins (lysozyme and bovine serum albumin (BSA)) with imidazolium-based ionic liquid surfactant (1-dodecyl-3-methyl imidazolium bromide ([C 12 mim]Br)) have been measured as a function of the surfactant concentration, interface lifetime and interfacial pressure. The dynamic interfacial dilational modulus of lysozyme/[C 12 mim]Br solutions are always monotonous, but that of the BSA/[C 12 mim]Br solutions become nonmonotonous indicating the destruction of the protein structure. One can assume that some lysozyme molecules desorb from interface due to competitive of free [C 12 mim]Br molecules for lysozyme/[C 12 mim]Br solution with [C 12 mim]Br concentration increasing, however, BSA molecules unfolding of compact globule have been subject to conformational changes so that it can give space for more [C 12 mim]Br molecules to co-adsorb. This aimed to provide more theoretical information for practical applications of imidazolium-based ionic liquid surfactant. [ABSTRACT FROM AUTHOR]

The effects of inorganic alkalis on the dynamic interfacial tensions (IFTs) of three betaine surfactants with different structures against daqing crude oil and model oils containing crude oil fractions, such as saturate, aromatic, resin, asphaltene and acidic fractions, have been studied by spinning drop tensiometer. The influences of pH value (alkali concentration and types) have been investigated. On the basis of the experimental results, one can find that it is difficult to reach the ultralow IFT value for all betaine solutions because of the mismatching of the hydrophilic head and hydrophobic tail. The unsaturated and branched alkyl chain can enlarge the size of hydrophobic part and reduce the equilibrium IFTs. By adding alkali, the IFTs are controlled by the mixed adsorptions of the petroleum acids, produced soaps and betaine molecules. For betaines with small hydrophobic part, 18C and 22C, the mixed adsorption films are compact than those of pure betaine films, which results in the decrease of IFT. On the other hand, the petroleum acids and soaps adsorb competitively with betaine molecules, due to the tighter packing of 26C molecules at the interface, the equilibrium IFT values of 26C increase with an increase in pH value. The stronger the alkali is, the better the synergism or antagonism is. The effects of pH on the IFTs of betaine solutions against model oils containing crude oil fractions agree with those against crude oil. For all betaines, the order of the ability of affecting IFT is acidic fractions > resin > asphaltene > aromatic > saturate in general. [ABSTRACT FROM AUTHOR]

1,3-Propylenediaminetetraacetic acid (1,3-H 4 pdta, C 11 H 18 N 2 O 8 ) is an aminopolycarboxylic acid and has been researched widely. It is a hexadentate (“six-toothed”) ligand as a typical chelating agent. In neutral solution, it mainly formed water-soluble monomeric coordination complexes [TM(1,3-pdta)(H 2 O) x ] y− (TM = transition metal; x = 0,1; y = 1,2) when coordinated with first transition metals. When involving lanthanide complexes, monomeric and dimeric complexes, different kinds of one-dimensional (1D) and two-dimensional (2D) coordination polymers were isolated. In acidic solution, the coordination modes of 1,3-pdta ligand were widely increased with the variation of acidity and temperature of the solution. [ABSTRACT FROM AUTHOR]

26 well selected oxidized P‐clusters (P2+) from the crystallographic data deposited in the Protein Data Bank have been analysed statistically by the bond‐valence sum method with weighting schemes for MoFe proteins at different resolutions. Interestingly, the oxidation states of P2+ clusters correspond to Fe23+Fe62+ with high electron delocalization, showing the same oxidation states as the resting states of P‐clusters (PN) in nitrogenases. The previously uncertain reduction of P2+ to PN clusters by two electrons was assigned as a double protonation of P2+, in which decoordination of the serine residue and the peptide chain of cysteine take place, in MoFe proteins. This is further supported by the obviously shorter α‐alkoxy C—O bond (average of 1.398 Å) in P2+ clusters and longer α‐hydroxy C—O bond (average of 1.422 Å) in PN clusters, while no change is observed in the electronic structures of Fe8S7 Fe atoms in P‐clusters. Spatially, the calculations show that Fe3 and Fe6, the most oxidized and most reduced Fe atoms, have the shortest distances of 9.329 Å from the homocitrate in the FeMo cofactor and 14.947 Å from the [Fe4S4] cluster, respectively, and may well function as important electron‐transport sites. [ABSTRACT FROM AUTHOR]