Search

Objective: PANoptosis, a new form of regulated cell death, concomitantly manifests hallmarks for pyroptosis, apoptosis, and necroptosis. It has been usually observed in macrophages, a class of widely distributed innate immune cells in various tissues, upon pathogenic infections. The second-generation curaxin, CBL0137, can trigger necroptosis and apoptosis in cancer-associated fibroblasts. This study aimed to explore whether CBL0137 induces PANoptosis in macrophages in vitro and in mouse tissues in vivo. Methods: Bone marrow-derived macrophages and J774A.1 cells were treated with CBL0137 or its combination with LPS for indicated time periods. Cell death was assayed by propidium iodide staining and immunoblotting. Immunofluorescence microscopy was used to detect cellular protein distribution. Mice were administered with CBL0137 plus LPS and their serum and tissues were collected for biochemical and histopathological analyses, respectively. Results: The results showed that CBL0137 alone or in combination with LPS induced time- and dose-dependent cell death in macrophages, which was inhibited by a combination of multiple forms of cell death inhibitors but not each alone. This cell death was independent of NLRP3 expression. CBL0137 or CBL0137 + LPS-induced cell death was characterized by simultaneously increased hallmarks for pyroptosis, apoptosis and necroptosis, indicating that this is PANoptosis. Induction of PANoptosis was associated with Z-DNA formation in the nucleus and likely assembly of PANoptosome. ZBP1 was critical in mediating CBL0137 + LPS-induced cell death likely by sensing Z-DNA. Moreover, intraperitoneal administration of CBL0137 plus LPS induced systemic inflammatory responses and caused multi-organ (including the liver, kidney and lung) injury in mice due to induction of PANoptosis in these organs. Conclusions: CBL0137 alone or plus inflammatory stimulation induces PANoptosis both in vitro and in vivo, which is associated with systemic inflammatory responses in mice. [ABSTRACT FROM AUTHOR]

A new Zn(II) metal–organic framework (MOF) with the formula [Zn(BBIP)(2,6-NDC)]n (JXUST-44, BBIP = 3,5-bis(1H-benzo[d]imidazol-1-yl)pyridine and 2,6-H2NDC = 2,6-naphthalic acid) was synthesized under solvothermal conditions. The adjacent Zn(II) ions are connected by BBIP ligands to form one-dimensional (1D) chains, which are further linked by carboxylate groups of 2,6-NDC2− ligands to obtain a two-dimensional layer structure, resulting in a 2D → 3D polycatenated MOF. JXUST-44 can be simplified as a 4-connected sql topology and shows good chemical stability in a wide pH range from 2 to 12 at room temperature. The fluorescence experiments indicate that JXUST-44 presents sensitive and selective detection of salicylaldehyde (SA), acetylacetone (acac) and H2PO4− with the detection limits of 0.074, 10.311 and 0.011 ppm, respectively. It is worth noting that JXUST-44 shows turn-on fluorescence toward acac and H2PO4−, as well as good recyclability and stability for acac, SA and H2PO4−. Therefore, JXUST-44 can be considered as a good fluorescent sensor for acac, SA and H2PO4−. The sensing mechanism has also been studied in detail. [ABSTRACT FROM AUTHOR]

High-resolution near-infrared observations with GRAVITY instrument have revealed rapid orbital motions of a hotspot around Sagittarius A* (Sgr A*), the supermassive black hole in our Galactic Centre, during its three bright flares. The projected distances of the spot to the black hole are measured and seem to increase with time. The values of distance, combined with the measured orbiting time, imply that the spot is rotating with a super-Keplerian velocity. These results are hard to understand if the spot stays within the accretion flow thus provides strong constraints on theoretical models for flares. Previously we have proposed a 'CME' model for the flares by analogy with the coronal-mass-ejection model in solar physics. In that model, magnetic reconnection occurred at the surface of the accretion flow results in the formation of flux ropes, which are then ejected out. Energetic electrons accelerated in the current sheet flow into the flux rope region and their radiation is responsible for the flares. In this paper, we apply the model to the interpretation of the GRAVITY results by calculating the dynamics of the ejected flux rope, the evolution of the magnetic field and the energy distribution of accelerated electrons, and the radiation of the system. We find that the model can well explain the observed light curve of the flares, the time-dependent distance, and the super-Keplerian motion of the hotspot. It also explains why the light curve of some flares has double peaks. [ABSTRACT FROM AUTHOR]

These years, two-dimensional (2D) superconductors have attracted more and more attentions. The critical temperature ( T c ) of superconductors can be modified by hole/electron doping, atom adsorption, strain and other means, so as to realize superconductivity with higher T c . In this paper, using first-principles calculations, we study the superconductivity of monolayer hexagonal boron phosphide (h-BP) by metal atoms adsorption. The electronic structure and electron-phonon coupling (EPC) of MBP (M=Li, Na, Ti) are studied. It is found that monolayer h-BP transforms from a semiconductor to a metal after metal atoms adsorption. Based on the conventional EPC mechanism, the coupling between electrons and the out-of-plane vibration of B atoms and P atoms contributes greatly to the EPC. For MBP (M=Li, Na, Ti), the calculated total EPC λ are 1.76, 0.64, and 1.54, and the corresponding T c are 26.38, 6.05, and 14.58 K, respectively. Thus, the predicted MBP (M=Li, Na, Ti) are new 2D superconductors which might be used in future superconducting electronic devices. [ABSTRACT FROM AUTHOR]

Objective To evaluate the accuracy of the reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in community or primary-care settings. Method We systematically searched the Web of Science, Embase, PubMed, and Cochrane Library databases. We conducted quality evaluation using ReviewManager software (version 5.0). We then used MetaDisc software (version 1.4) and Stata software (version 12.0) to build forest plots, along with a Deeks funnel plot and a bivariate boxplot for analysis. Result Overall, the sensitivity, specificity, and diagnostic odds ratio were 0.79, 0.97, and 328.18, respectively. The sensitivity for the subgroup with RNA extraction appeared to be higher, at 0.88 (0.86–0.90), compared to the subgroup without RNA extraction, at 0.50 (0.45–0.55), with no significant difference in specificity. Conclusion RT-LAMP assay exhibited high specificity regarding current SARS-CoV-2 infection. However, its overall sensitivity was relatively moderate. Extracting RNA was found to be beneficial in improving sensitivity. [ABSTRACT FROM AUTHOR]

Quantum key distribution (QKD) allows authenticated parties to share secure keys. Its security comes from quantum physics rather than computational complexity. The previous work has been able to demonstrate the security of the BB84 protocol based on the uncertainty principle, entanglement purification and information theory. In the security proof method based on entanglement purification, it is assumed that the information of Calderbank–Shor–Steane (CSS) error correction code cannot be leaked, otherwise, it is insecure. However, there is no quantitative analysis of the relationship between the parameter of CSS code and the amount of information leaked. In the attack and defense strategy of the actual quantum key distribution system, especially in the application of the device that is easy to lose or out of control, it is necessary to assess the impact of the parameter leakage. In this paper, we derive the relationship between the leaked parameter of CSS code and the amount of the final key leakage based on the BB84 protocol. Based on this formula, we simulated the impact of different CSS code parameter leaks on the final key amount. Through the analysis of simulation results, the security of the BB84 protocol is inversely proportional to the value of n − k 1 and k 1 − k 2 in the case of the CSS code leak. [ABSTRACT FROM AUTHOR]

Background: This research aimed to explore the association between the RIG-I-like receptor (RIG-I and MDA5 encoded by DDX58 and IFIH1, respectively) pathways and the risk or severity of hand, foot, and mouth disease caused by enterovirus 71 (EV71-HFMD). In this context, we explored the influence of gene methylation and polymorphism on EV71-HFMD. Methodology/Principal findings: 60 healthy controls and 120 EV71-HFMD patients, including 60 mild EV71-HFMD and 60 severe EV71-HFMD patients, were enrolled. First, MiSeq was performed to explore the methylation of CpG islands in the DDX58 and IFIH1 promoter regions. Then, DDX58 and IFIH1 expression were detected in PBMCs using RT-qPCR. Finally, imLDR was used to detect DDX58 and IFIH1 single-nucleotide polymorphism (SNP) genotypes. Severe EV71-HFMD patients exhibited higher DDX58 promoter methylation levels than healthy controls and mild EV71-HFMD patients. DDX58 promoter methylation was significantly associated with severe HFMD, sex, vomiting, high fever, neutrophil abundance, and lymphocyte abundance. DDX58 expression levels were significantly lower in mild patients than in healthy controls and lower in severe patients than in mild patients. Binary logistic regression analysis revealed statistically significant differences in the genotype frequencies of DDX58 rs3739674 between the mild and severe groups. GeneMANIA revealed that 19 proteins displayed correlations with DDX58, including DHX58, HERC5, MAVS, RAI14, WRNIP1 and ISG15, and 19 proteins displayed correlations with IFIH1, including TKFC, IDE, MAVS, DHX58, NLRC5, TSPAN6, USP3 and DDX58. Conclusions/Significance: DDX58 expression and promoter methylation were associated with EV71 infection progression, especially in severe EV71-HFMD patients. The effect of DDX58 in EV71-HFMD is worth further attention. Author summary: EV71-HFMD is now prevalent in many Asia countries, including China, which caused a lot of death over the last few years. Therefore, it's important to distinguish patients with a severe tendency. In this research, we investigated the association between the epigenetic mechanisms of RIG-I-like pattern recognition receptors (DDX58 and IFIH1) and EV71-HFMD. It showed that children with higher level of DDX58 promoter methylation were related to severe EV71-HFMD and other clinical indicators. The DDX58 mRNA expression level was significantly lower in severe patients. Besides, DDX58 polymorphisms played an important role in the severity of EV71-HFMD. Therefore, various epigenetic biomarkers of DDX58 may be used as indicators to help clinicians identify EV71-HFMD patients with a tendency towards severity. [ABSTRACT FROM AUTHOR]

We perform a series of high-resolution 2D hydrodynamical simulations of equal-mass binary black holes (BBHs) embedded in active galactic nucleus (AGN) accretion disks to study whether these binaries can be driven to merger by the surrounding gas. We find that the gravitational softening adopted for the BBH has a profound impact on this result. When the softening is less than 10% of the binary separation, we show that, in agreement with recent simulations of isolated equal-mass binaries, prograde BBHs expand in time rather than contract. Eventually, however, the binary separation becomes large enough that the tidal force of the central AGN disrupts them. Only when the softening is relatively large do we find that prograde BBHs harden. We determine through detailed analysis of the binary torque, that this dichotomy is due to a loss of spiral structure in the circum-single disks orbiting each black hole when the softening is a significant fraction of the binary separation. Properly resolving these spirals—both with high resolution and small softening—results in a significant source of binary angular momentum. Only for retrograde BBHs do we find consistent hardening, regardless of softening, as these BBHs lack the important spiral structure in their circum-single disks. This suggests that the gas-driven inspiral of retrograde binaries can produce a population of compact BBHs in the gravitational-wave-emitting regime in AGN disks, which may contribute a large fraction to the observed BBH mergers. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium tuberculosis (MTB). An estimated 1.7 billion people worldwide are infected with Mycobacterium tuberculosis (LTBI) during the incubation period without any obvious symptoms. Because of MTB's high infection and mortality rates, there is an urgent need to develop a fast, portable, and sensitive diagnostic technology for its detection.Methods: We included research from PubMed, Cochrane Library, Web of Science, and Embase and extracted the data. MetaDisc and STATA were used to build forest plots, Deek's funnel plot, Fagan plot, and bivariate boxplot for analysis.Results: Forty-six articles were analyzed, the results of which are as follows: sensitivity and specificity were 0.92 (0.91-0.93) and 0.95 (0.94-0.95) respectively. The NLR and PLR were 0.04 (95% CI 0.03-0.07) and 25.32 (95% CI 12.38-51.78) respectively. DOR was 639.60 (243.04-1683.18). The area under the SROC curve (AUC) was 0.99.Conclusions: MPT64 exhibits good diagnostic efficiency for MTB. There is no obvious heterogeneity between the three commercial kits. [ABSTRACT FROM AUTHOR]

Severe hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) infection is associated with high mortality and disability. DC-SIGN, a receptor for EV71, is widely distributed in dendritic cells and may influence the severity of HFMD caused by EV71 infection. This observational study attempts to explore whether single-nucleotide polymorphisms (SNPs) in DC-SIGN are related to the severity of EV71-associated HFMD. Based on linkage disequilibrium and functional predictions, two DC-SIGN SNPs were selected and tested to explore their potential association with the severity of HFMD caused by EV71 infection. Two hundred sixteen Han Chinese children with HFMD caused by EV71 were enrolled to obtain clinical data, including the severity of HFMD, serum DC-SIGN levels, and DC-SIGN SNPs. We found a significant association between the rs7248637 polymorphism (A vs. G: OR = 0.644, 95% CI = 0.515-0.806) and the severity of HFMD caused by EV71 infection, as well as the rs4804800 polymorphism (A vs. G: OR = 1.539, 95% CI =1.229-1.928). These two DC-SIGN SNPs may have an effect on the severity of HFMD caused by EV71 infection. [ABSTRACT FROM AUTHOR]

• Hand, foot and mouth disease induced by enterovirus 71 (EV71-HFMD) can lead to high morbidity and mortality. • Interferon-induced transmembrane protein 3 (IFITM3) is an antiviral protein. Its overexpression can suppress the infection efficiency of many viruses. • IFITM3 single-nucleotide polymorphism (SNP) genotype, promoter methylation and mRNA expression of peripheral blood mononuclear cells were correlated with the progression of EV71 infection, especially in patients with severe EV71-HFMD. • IFITM3 methylation status and SNP genotype may help clinicians to choose the correct treatment strategy for patients with EV71-HFMD. To explore the mechanisms of interferon-induced transmembrane protein 3 (IFITM3) in response to enterovirus-71-associated hand, foot and mouth disease (EV71-HFMD), in terms of DNA methylation, single-nucleotide polymorphism (SNP) genotype and gene expression. In total, 120 patients with EV71-HFMD (60 with mild EV71-HFMD and 60 with severe EV71-HFMD) and 60 healthy controls were enrolled in this study. SNP genotype, IFITM3 promoter methylation and mRNA expression of peripheral blood mononuclear cells were examined using the improved multi-temperature ligase detection reaction, quantitative reverse transcriptase polymerase chain reaction and MiSeq, respectively. The distribution of methylation in patients with EV71-HFMD was significantly lower compared with healthy controls, and the severe EV71-HFMD group showed the lowest frequency of IFITM3 promoter methylation. The average level of IFITM3 promoter CpG methylation was negatively correlated with IFITM3 mRNA expression, and hypermethylation of several specific CpG units contributed to IFITM3 downregulation. IFITM3 expression and promoter methylation correlated with EV71 infection progression, especially in the severe EV71-HFMD group. Compared with mild cases, genotype GG and the G allele of rs12252 were over-represented in patients with severe EV71-HFMD. IFITM3 methylation status and SNP genotyping may help clinicians to choose the correct treatment strategy for patients with EV71-HFMD. [ABSTRACT FROM AUTHOR]

After protoplanets have acquired sufficient mass to open partial gaps in their natal protostellar disks, residual gas continues to diffuse onto horseshoe streamlines under the effect of viscous dissipation, and to meander in and out of the planets' Hill sphere. Within the Hill sphere, the horseshoe streamlines intercept gas flow in circumplanetary disks. The host star's tidal perturbation induces a barrier across the converging streamlines' interface. Viscous transfer of angular momentum across this tidal barrier determines the rate of mass diffusion from the horseshoe streamlines onto the circumplanetary disks, and eventually the accretion rate onto the protoplanets. We carry out a series of numerical simulations to test the influence of this tidal barrier on superthermal planets. In weakly viscous disks, the protoplanets' accretion rate steeply decreases with their masses above the thermal limit. As their growth timescale exceeds the gas depletion timescale, their masses reach asymptotic values comparable to that of Jupiter. In relatively thick and strongly viscous disks, protoplanets' asymptotic masses exceed several times that of Jupiter. Two-dimensional numerical simulations show that such massive protoplanets strongly excite the eccentricity of nearby horseshoe streamlines, destabilize orderly flow, substantially enhance the diffusion rate across the tidal barrier, and elevate their growth rate until their natal disk is severely depleted. In contrast, eccentric streamlines remain stable in three-dimensional simulations. Based on the upper falloff in the observed mass distribution of known exoplanets, we suggest that their natal disks had relatively low viscosity (α ∼ 10−3) and modest thickness (H/R ∼ 0.03–0.05). [ABSTRACT FROM AUTHOR]

Background. The pathogenesis of invasive aspergillosis (IA) is still unknown, but its progression is rapid and mortality rate remains high. Bronchoalveolar lavage fluid (BALF) galactomannan (GM) analysis has been used to diagnose IA. This study is aimed at making an accurate estimate of the whole accuracy of BALF-GM in diagnosing IA. Methods. After a systematic review of the study, a bivariate meta-analysis was used to summarize the specificity (SPE), the sensitivity (SEN), the positive likelihood ratios (PLR), and the negative likelihood ratios (NLR) of BALF-GM in diagnosing IA. The overall test performance was summarized using a layered summary receiver operating characteristic (SROC) curve. Subgroup analysis was performed to explore the heterogeneity between studies. Results. A total of 65 studies that are in line with the inclusion criteria were included. The summary estimates of BALF-GM analysis are divided into four categories. The first is the proven+probable vs. possible+no IA, with an SPE, 0.87 (95% CI, 0.85-0.98); SEN, 0.81 (95% CI, 0.76-0.84); PLR, 9.78 (5.78-16.56); and NLR, 0.20 (0.14-0.29). The AUC was 0.94. The BALF-GM test for proven+probable vs. no IA showed SPE, 0.88 (95% CI, 0.87-0.90); SEN, 0.82 (95% CI, 0.78-0.85); PLR, 6.56 (4.93-8.75); and NLR, 0.24 (0.17-0.33). The AUC was 0.93. The BALF-GM test for proven+probable+possible vs. no IA showed SPE, 0.82 (95% CI, 0.79-0.95); SEN, 0.59 (95% CI, 0.55-0.63); PLR, 3.60 (2.07-6.25); and NLR, 0.31 (0.15-0.61). The AUC was 0.86. The analyses for others showed SPE, 0.85 (95% CI, 0.83-0.87); SEN, 0.89 (95% CI, 0.86-0.91); PLR, 6.91 (4.67-10.22); and NLR, 0.18 (0.13-0.26). The AUC was 0.94. Conclusions. The findings of this BALF-GM test resulted in some impact on the diagnosis of IA. The BALF-GM assay is considered a method for diagnosing IA with high SEN and SPE. However, the patients' underlying diseases may affect the accuracy of diagnosis. When the cutoff is greater than 1, the sensitivity will be higher. [ABSTRACT FROM AUTHOR]

To evaluate the epigenetic regulation of the VDR gene in enterovirus 71 (EV71)-associated severe hand, foot, and mouth disease (HFMD), a total of 116 patients with EV71-HFMD, including 58 with mild EV71-HFMD and 58 with severe EV71-HFMD, as well as 60 healthy controls, were enrolled in this study. Quantitative real-time PCR was used to measure the relative levels of VDR mRNA expression, and the methylation status of the VDR promoter was assessed using a MethylTarget™ assay. The DNA methylation levels of the VDR promoter in children with EV71-associated severe HFMD were lower than those in the healthy controls and in children with mild HFMD (P < 0.05). Hypomethylation at CpG site 133 and hypermethylation at the CpG 42 sites and 68 downregulated VDR expression. Moreover, the methylation level of VDR could be used for differential diagnosis of mild and severe EV71-associated HFMD (AUC56, 0.73; AUC68, 0.699; AUC42, 0.694; AUC66, 0.693). VDR expression and promoter methylation were associated with the progression of EV71 infection. Determining the VDR promoter status might help clinicians initiate the appropriate strategy for treatment of EV71-associated HFMD. [ABSTRACT FROM AUTHOR]

The omnipresence of super-Earths suggests that they are able to be retained in natal disks around low-mass stars, whereas exoplanets' mass distributions indicate that some cores have transformed into gas giants through runaway gas accretion at ≳1 au from solar-type stars. In this paper, we show that transition to runaway gas accretion by cores may be self-impeded by an increase of the grain opacity in their envelope after they have acquired sufficient mass (typically ∼ 10M⊕) to enter a pebble-isolation phase. The accumulation of approximately millimeter- to meter-sized pebbles in their migration barriers enhances their local fragmentation rates. The freshly produced submillimeter grains pass through the barrier, elevate the effective dust opacity, and reduce the radiative flux in the core's envelope. These effects alone are adequate to suppress the transition to runaway accretion and preserve super-Earths in the stellar proximity (∼0.1 au), albeit entropy advection between the envelope and the disk can further reduce the accretion rate. At an intermediate distance (∼1 au) from their host stars, the escalation in the dust opacity dominates over entropy advection in stalling the transition to runaway accretion for marginally pebble-isolated cores. Beyond a few astronomical unit, the transformation of more-massive cores to gas giants is reachable before severe depletion of disk gas. This requirement can be satisfied either in extended disks with large scale height via orderly accretion of migrating pebbles or through the mergers of oligarchic protoplanetary embryos, and can account for the correlated occurrence of long-period gas giants and close-in super-Earths. [ABSTRACT FROM AUTHOR]

We investigate the impact of a highly eccentric 10 M⊕ (where M⊕ is the Earth mass) planet embedded in a dusty protoplanetary disk on dust dynamics and its observational implications. By carrying out high-resolution 2D gas and dust two-fluid hydrodynamical simulations, we find that the planet's orbit can be circularized at large radii. After the planet's orbit is circularized, partial gap opening and dust ring formation happen close to the planet's circularization radius, which can explain the observed gaps/rings at the outer region of disks. When the disk mass and viscosity become low, we find that an eccentric planet can even open gaps and produce dust rings close to the pericenter and apocenter radii before its circularization. This offers alternative scenarios for explaining the observed dust rings and gaps in protoplanetary disks. A lower disk viscosity is favored to produce brighter rings in observations. An eccentric planet can also potentially slow down the dust radial drift in the outer region of the disk when the disk viscosity is low (α ≲ 2 × 10−4) and the circularization is faster than the dust radial drift. [ABSTRACT FROM AUTHOR]

A novel modified polyoxometalate, {PMo12O40[Cu(2,2′‐bpy)]}[Cu(2,2′‐bpy)(en)(H2O)]2 [2,2′‐bpy is 2,2′‐bipyridyl (C10H8N2) and en is ethylenediamine (C2H8N2)], has been synthesized hydrothermally and structurally characterized by elemental analysis, TG, IR, XPS and single‐crystal X‐ray diffraction. The structural analysis reveals that the compound contains the reduced Keggin polyanion [PMo12O40]6− as the parent unit, which is monocapped by [Cu(2,2′‐bpy)]2+ fragments via four bridging O atoms on an {Mo4O4} pit and bi‐supported by two [Cu(2,2′‐bpy)(en)(H2O)]2+ coordination cations simultaneously. There exist strong intramolecular π–π stacking between the capping and supporting units, which play a stabilizing role during the crystallization of the compound. Adjacent POM clusters are further aggregated to form a three‐dimensional supramolecular network through noncovalent forces, hydrogen bonding and π–π stacking interactions. In addition, the photocatalytic properties were investigated in detail, and the results indicated that the compound can be used as a photocatalyst towards the decomposition of the organic pollutant methylene blue (MB). [ABSTRACT FROM AUTHOR]

A metal–organic framework (MOF)-conductive polymer composite film modified electrode was constructed by drop casting using PCN-222(Fe) and p3HT-p3TPA copolymer. Introduction of carboxylate groups to the polymer matrix enhances interaction between polymer and MOF particles, leading to enhanced electron transfer and better water stability. The modified electrode was used for electrochemical detection of nitrobenzene in aqueous solution with a wide linear detection range of 0.05 μM–100 μM and a low detection limit of 0.047 μM. [Display omitted] • Composite films of metal–organic frameworks (MOFs) and conductive polymers was fabricated. • Conductive polymers with carboxylic acid functional groups increase MOF stability in aqueous solution as well as electron transfer rates due to their strong interaction with MOF particles. • The MOF-conductive polymer film could be used as electrochemical sensor for nitrobenzene with the detection limit as low as 0.05 µM. A metal–organic framework (MOF)-conductive polymer composite film modified electrode was constructed by drop casting using PCN-222(Fe) and p3HT-p3TPA copolymer. The composite materials were characterized by diffraction, spectroscopic and electron microscopic techniques, showing the uniform distribution of MOF particles in the polymer matrix with the original MOF structure maintained. Introduction of carboxylate groups to the polymer matrix enhances interaction between polymer and MOF particles, leading to enhanced electron transfer and better water stability. The modified electrode was used for electrochemical detection of nitrobenzene in aqueous solution with the wide linear detection ranges of 0.05 μM-1.00 μM (0.6572 μAμM−1) and 1.00 μM-100 μM (0.03304 μAμM−1) as well as a low detection limit of 0.047 μM. [ABSTRACT FROM AUTHOR]

Explicit internal signal stochastic resonance (EISSR) is investigated in a model of energy transduction of molecular machinery when noise is added to the region of oscillation in the presence of external signal (ES). It is found that EISSR could be controlled, i.e., enhanced or suppressed by adjusting frequency (ωe) and amplitude (A) of ES, and that there exits an optimal frequency for ES, which makes EISSR strength reach the maximum. Meanwhile, a critical amplitude (Ac) is found, which is a threshold of occurrence of EISSR. Finally, the difference and similarity between EISSR and IISSR (implicit internal signal stochastic resonance) are discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Internal stochastic resonance (ISR) in a model of intercellular calcium ion oscillations is investigated under the modulation of two parameters, viz., degree of extracellular stimulation (β) and leak rate (kf). ISR can occur when either β or kf is subjected to a noise. Internal stochastic biresonance (ISBR) can occur when noise is added to the two parameters simultaneously. The distance to the bifurcation point is found to be able to enhance or suppress the ISBR, and to affect the number of peaks of ISR. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Many analyses have concluded that the accretion disc sizes measured from the microlensing variability of quasars are larger than the expectations from the standard thin disc theory by a factor of ∼4. We propose a simple model by invoking a strong wind from the disc to flatten its radial temperature profile, which can then reconcile the size discrepancy problem. This wind model has been successfully applied to several microlensed quasars with a wind strength s ≲ 1.3 by only considering the inward decreasing of the mass accretion rate [where s is defined through |$\dot{M}(R)\propto ({R}/{R_{0}})^{s}$| ]. After further incorporating the angular momentum transferred by the wind, our model can resolve the disc size problem with an even lower wind parameter. The corrected disc sizes under the wind model are correlated with black hole masses with a slope in agreement with our modified thin disc model. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) presents a significant challenge to global healthcare systems, with current treatments offering only modest relief and often bringing unwanted side effects, necessitating the exploration of more effective and safer drugs. In this study, we employed the Caenorhabditis elegans (C. elegans) model, specifically the AD-like CL4176 strain expressing the human Aβ(1–42) protein, to investigate the potential of Reineckia carnea extract and its fractions. Our results showed that the Reineckia carnea ether fraction (REF) notably diminished the paralysis rates of CL4176 worms. Additionally, REF also attenuated the neurotoxicity effects prompted by Tau proteins in the BR5270 worms. Moreover, REF was observed to counteract the accumulation of Aβ and pTau proteins and their induced oxidative stress in C. elegans AD-like models. Mechanistic studies revealed that REF's benefits were associated with the induction of autophagy in worms; however, these protective effects were nullified when autophagy-related genes were suppressed using RNAi bacteria. Together, these findings highlight Reineckia carnea ether fraction as a promising candidate for AD treatment, warranting further investigation into its autophagy-inducing components and their molecular mechanisms. [ABSTRACT FROM AUTHOR]

The mitochondrial toxicity induced by GSH-CdTe Quantum dots (QDs) of different sizes was investigated. The decreases in absorbance and transmission electron microscopy images show that QDs induce the swelling of mitochondria. Results of flow cytometry indicate that QDs cause a reduction of mitochondrial membrane potential (MMP). A remarkable increase in fluidity of protein regions of mitochondrial membrane is observed, whereas the lipid regions are not obviously affected. Cyclosporin A (CsA) effectively prevents the QD-induced mitochondrial swelling. On the basis of these results, it is proposed that QDs induce mitochondrial permeability transition (MPT). Moreover, with increasing QDs size, a pronounced MPT is observed. The difference between the membrane fluidity induced by QDs and Cadmium ion and the ineffective protective effects of EDTA suggests that the mitochondrial toxicity of QDs cannot be only attributed to the release of metal ion. The protective effects of HSA indicate that the interaction of QDs with pore-forming protein gives rise to the increase in membrane fluidity. This hypothesis is demonstrated by the interaction of QDs with model membranes and proteins using differential scanning calorimetry and isothermal titration microcalorimetry. In conclusion, as the size of QDs increases, the binding affinity of QDs with membrane protein increases, and therefore causes a pronounced mitochondrial damage. [ABSTRACT FROM AUTHOR]

The key issue of the purpose of detecting target vehicle speed based on video is how to obtain the accurate and efficient real-time information of moving targets using the video sequence in unstructured environment. Vehicle speed detection based on visual perception mechanism is a kind of new method. Visual mechanism inspired the method, first of all it should learn the over-complete characterization of primary visual cortex cells from nature images. Then it compared with the dynamic threshold to identify the moving target based on over-complete visual calculation model according to neuron response coefficient characterization and the difference of neuronal response coefficient between background images and goal images. Next, it achieved target tracking through the iterative method. Compared with the traditional method it got the displacement of the vehicle according to the matching method of characteristics in different video sequences on the basis of target tracking. Finally it could realize speed detection by this algorithm. Experimental results show that this algorithm can test the vehicle speed of different types in the actual road scene under real-time conditions and reach more than 96.55% accuracy. The algorithm improves the vehicle speed detection in accuracy and robustness compared with the traditional method. [ABSTRACT FROM AUTHOR]

A novel artificial receptor 1 containing the indolocarbazole-NH moieties as the recognition sites exhibited high selectivity and sensitivity toward F − over other typical anionic species in DMSO solution. Upon addition of F − into the solution, receptor 1 showed a remarkable ratiometric shift of the fluorescence maximum from 535 to 590 nm, and also a prominent color change from light yellow to orange, which was observable by the naked eye. The recognition properties of receptor 1 were investigated by 1 H NMR, UV–vis, and fluorescence titration experiments, with the results suggesting a two-step strategy of binding with F − . In addition, the theoretical calculations were carried out to reveal the role of intramolecular charge transfer in the ratiometric fluorescence recognition process. [ABSTRACT FROM AUTHOR]

Highlights: [•] The impurity profiling of meleumycin were characterized by LC/PDA/ESI-MS/MS. [•] Twelve impurities that had never been reported before were identified. [•] Twelve others were partially characterized. [Copyright &y& Elsevier]

The synthesis, characterization and ion binding properties of a new ditopic ratiometric receptor (1), based on 2-(4,5-dihydro-1H-imidazol-2-yl)phenol and crown ether moieties, have been described. The ditopic ratiometric receptor has been studied in sensing both F− and Zn2+ ions, exhibiting different fluorescent colour changes from cyan green to blue/black observable by the naked eye under UV-light. The addition of Zn2+ to the solution of 1 induced the formation of a 2 : 2 ligand–metal complex 1–Zn2+, which displays a remarkable blue shift of the emission maxima of 1 from 455 nm to 400 nm due to the inhibition of excited-state intramolecular proton transfer (ESIPT) mechanism. The sensing processes were monitored by fluorescence/absorption titrations, and further confirmed by Job's plot and 1H NMR titrations. The crystal structure of 1–Zn2+ reveals that 1 binds Zn2+ in four-coordinated modes. Furthermore, 1 is cell permeable and may be applied to detect trace Zn2+ and F− during the development of a living organism. [ABSTRACT FROM AUTHOR]

Abstract: A new receptor based on a dibenzo-18-crown-6 derivative is successfully synthesized and characterized. This receptor reveals selective recognition toward Al3+ ion, along with colorimetric and fluorometric dual-signaling responses based on internal charge transfer (ICT). Also, it can serve as a highly selective chemodosimeter for Al3+ with naked-eye detection. [Copyright &y& Elsevier]

Abstract: A new ditopic ion pair receptor 1 containing two biindole moieties and a bis-benzocrown ether unit shows a remarkable color switching (ON- and -OFF) function induced by anion (F−) and cation (K+) recognition. The ditopic receptor 1 binds in a cooperative fashion to HSO4 − in the presence of 1·K+ and acts as a selective ditopic receptor to recognize ion pairs with a wavelength-ratiometric manner. [Copyright &y& Elsevier]

Abstract: We present an atomistic study on the phase stability, site preference and lattice constants of the rare earth or actinium intermetallics Ce6Rh30Si19 and A6Pt30Si19 (A=Th, U). The calculated preferential occupation site of one Si atom is found to be the 2b site in Ce6Rh30Si19 and A6Pt30Si19. The Si atom is located at the sites 2b with occupancy close to 50%. Our calculated lattice constants agree with a report in the literature. The total and partial phonon densities of states are evaluated first for these complicated defect structures. The analysis of the inverted potentials explains qualitatively the contributions of different atoms to the vibrational modes. [Copyright &y& Elsevier]

Using heart-type fatty acid-binding protein (H-FABP) as an early cardiac marker for diagnosis of acute myocardial infarction (AMI) soon after the onset of symptoms requires a rapid assay. A one-step test called, CardioDetect®, is used for detection of H-FABP in whole blood sample. Thirty patients suspected of AMI presenting to the emergency department within 12 hours after onset were enrolled in this study. The diagnostic performance of CardioDetect® was compared with different cardiac markers. There were 59.1% of patients with positive H-FABP within 6 hours after onset, while there were only 18.2% with positive cardiac troponin I (cTnI). Results indicated the diagnostic power of H-FABP for AMI was significantly higher than that of cTnI. The sensitivity of H-FABP was 81.8%, which was higher than those of the other cardiac markers, while the specificity was comparable. The area under the receiver operating characteristic curve for H-FABP was 0.909, which was significantly larger than the others. With this rapid and sensitive immunotest, H-FABP could be soon introduced in clinical practice in combination with well-established markers like troponins. [ABSTRACT FROM AUTHOR]

Abstract: Noise-induced Ca2+ signal (NICS) was explored in Ca2+ system. But how far from the bifurcation point, could one get the admissible region of NICS? We proposed and demonstrated numerically that there existed a critical threshold of NICS, and discussed the relationships of the noise intensity, the distance to the bifurcation point, and the critical threshold. Furthermore, the detailed bifurcation diagram for certain noise intensity was renewed. Finally, it was found that not all the NICS but partial NICS was optimized selectively with the assistance of noise. [Copyright &y& Elsevier]

Abstract: The group delay of the dense wavelength division multiplexing (DWDM) filter is becoming more important in optical communication. This study proposes a Mach–Zehnder interferometer based on the direct group delay measurement of an optical thin film filter. The interferometer provides a simple, accurate and physically intuitive picture of what happens to broadband optical pulses on common optical materials. A 100GHz DWDM filter was used as an example in the measurement and showed that the time of measurement and selection of Gaussian window were two important factors. [Copyright &y& Elsevier]

Abstract: Responses of Ca2+ oscillations to random perturbation are investigated at the conditions where the system stays at a steady state (before bifurcation point) or an oscillatory state (after bifurcation point). It is found that noise can induce both implicit and explicit internal signal stochastic resonance (IISSR and EISSR). In particular, the internal signal stochastic bi-resonance is also observed. When an external signal is added to the system, no IISSR or EISSR phenomenon occurs, implying an external signal destroys cooperation of Ca2+ signal and environment noise. [Copyright &y& Elsevier]

Explicit internal signal stochastic resonance (EISSR) is investigated numerically when noise is added to the region of periodic-2 oscillatory state in intercellular calcium ion oscillations. It is found that the signal-to-noise ratio (SNR) of strong signal (SS) has a maximum value at an optimal noise intensity and that of weak signal (WS) increases monotonously with the increment of noise intensity. These results indicate that the EISSR has selectivity to two intrinsic signals of system. Moreover, the frequencies of SS and WS hardly change, which implies that system can resist to the effect of noise and sustain intrinsic period oscillatory states. [Copyright &y& Elsevier]

Internal stochastic resonance (ISR) in a liquid membrane oscillator is investigated by varying frequency (ωs) and amplitude (A) of an external signal (ES) in the presence of environment noise. It is found that the enhancement or suppression of ISR depends on frequency and amplitude of ES. In the range of low frequency (0.03–0.12 Hz), ISR appears and noise can transfer energy of ES to IS both for A=0.02 M and for A=0.15 M. In the range of high frequency (0.26–0.32 Hz), there exits an optimal frequency for ES, which is equal to frequency of IS and makes ISR strength reach maximum for A=0.02 M; but ISR disappears for A=0.15 M. At the optimal frequency ωs=0.28 Hz, a critical amplitude Ac for ES is found, less than which, ISR appears, and more than which, ISR disappears. [Copyright &y& Elsevier]

Damage-associated molecular patterns (DAMPs) such as extracellular ATP and nigericin (a bacterial toxin) not only act as potassium ion (K+) efflux inducers to activate NLRP3 inflammasome, leading to pyroptosis, but also induce cell death independently of NLRP3 expression. However, the roles of energy metabolism in determining NLRP3-dependent pyroptosis and -independent necrosis upon K+ efflux are incompletely understood. Here we established cellular models by pharmacological blockade of energy metabolism, followed by stimulation with a K+ efflux inducer (ATP or nigericin). Two energy metabolic inhibitors, namely CPI-613 that targets α-ketoglutarate dehydrogenase and pyruvate dehydrogenase (a rate-limiting enzyme) and 2-deoxy- d -glucose (2-DG) that targets hexokinase, are recruited in this study, and Nlrp3 gene knockout macrophages were used. Our data showed that CPI-613 and 2-DG dose-dependently inhibited NLRP3 inflammasome activation, but profoundly increased cell death in the presence of ATP or nigericin. The cell death was K+ efflux-induced but NLRP3-independent, which was associated with abrupt reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, and oligomerization of mitochondrial proteins, all indicating mitochondrial damage. Notably, the cell death induced by K+ efflux and blockade of energy metabolism was distinct from pyroptosis, apoptosis, necroptosis or ferroptosis. Furthermore, fructose 1,6-bisphosphate, a high-energy intermediate of glycolysis, significantly suppressed CPI-613+nigericin-induced mitochondrial damage and cell death. Collectively, our data show that energy deficiency diverts NLRP3 inflammasome activation-dependent pyroptosis to Nlrp3 -independent necrosis upon K+ efflux inducers, which can be dampened by high-energy intermediate, highlighting a critical role of energy metabolism in cell survival and death under inflammatory conditions. [Display omitted] • ATP or nigericin induces potassium ion (K+) efflux, thus inducing NLRP3 inflammasome activation. • K+ efflux leads to exaggerated cell death when energy metabolism is pharmacologically blocked. • The cell death induced by K+ efflux and energy metabolism blockade is independent of Nlrp3. • K+ efflux induces oxidative burst in mitochondria under condition of energy metabolism blockade. • K+ efflux induces exaggerated mitochondrial damage when energy metabolism is blocked. [ABSTRACT FROM AUTHOR]

Itaconate is an unsaturated dicarboxylic acid that is derived from the decarboxylation of the Krebs cycle intermediate cis-aconitate and has been shown to exhibit anti-inflammatory and anti-bacterial/viral properties. But the mechanisms underlying itaconate's anti-inflammatory activities are not fully understood. Necroptosis, a lytic form of regulated cell death (RCD), is mediated by receptor-interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like protein (MLKL) signaling. It has been involved in the pathogenesis of organ injury in many inflammatory diseases. In this study, we aimed to explore whether itaconate and its derivatives can inhibit necroptosis in murine macrophages, a mouse MPC-5 cell line and a human HT-29 cell line in response to different necroptotic activators. Our results showed that itaconate and its derivatives dose-dependently inhibited necroptosis, among which dimethyl itaconate (DMI) was the most effective one. Mechanistically, itaconate and its derivatives inhibited necroptosis by suppressing the RIPK1/RIPK3/MLKL signaling and the oligomerization of MLKL. Furthermore, DMI promoted the nuclear translocation of Nrf2 that is a critical regulator of intracellular redox homeostasis, and reduced the levels of intracellular reactive oxygen species (ROS) and mitochondrial superoxide (mtROS) that were induced by necroptotic activators. Consistently, DMI prevented the loss of mitochondrial membrane potential induced by the necroptotic activators. In addition, DMI mitigated caerulein-induced acute pancreatitis in mice accompanied by reduced activation of the necroptotic signaling in vivo. Collectively, our study demonstrates that itaconate and its derivatives can inhibit necroptosis by suppressing the RIPK1/RIPK3/MLKL signaling, highlighting their potential applications for treating necroptosis-associated diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phenolic endocrine‐disrupting chemicals (EDCs) are widespread and easily ingested through the food chain. They pose a serious threat to human health. Magnetic solid‐phase extraction (MSPE) is an effective sample pre‐treatment technology to determine traces of phenolic EDCs. RESULTS: Magnetic covalent organic framework (COF) (Fe3O4@COF) nanospheres were prepared and characterized. The efficient and selective extraction of phenolic EDCs relies on a large specific surface and the inherent porosity of COFs and hydrogen bonding, π–π, and hydrophobic interactions between COF shells and phenolic EDCs. Under optimal conditions, the proposed magnetic solid‐phase extraction‐high‐performance liquid chromatography–ultra violet (MSPE‐HPLC‐UV) based on the metallic covalent organic framework method for phenolic EDCs shows good linearities (0.002–6 μg mL−1), with R2 of 0.995 or higher, and low limits of detection (6–1.200 ng mL−1). CONCLUSION: Magnetic covalent organic frameworks (Fe3O4@COFs) with good MSPE performance for phenolic EDCs were synthesized by the solvothermal method. The magnetic covalent organic framework‐based MSPE‐HPLC‐UV method was applied successfully to determine phenolic EDCs in beverage and water samples with satisfactory recoveries (90.200%–123%) and relative standard deviations (2.100%–12.100%). © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Studying a centi-parsec supermassive black hole binary (SMBHB) would allow us to explore a new parameter space in active galactic nuclei, and these objects are also potential sources of gravitational waves. We report evidence that an SMBHB with an orbital period of ∼30 yr may be resident in the nearby galactic nucleus M81. This orbital period and the known mass of M81 imply an orbital separation of ∼0.02 pc. The jet emanating from the primary black hole showed a short period of jet wobbling at ∼16.7 yr, superposing a long-term precession at a timescale of several hundred years. Periodic radio and X-ray outbursts were also found two times per orbital period, which could be explained by a double-peaked mass accretion rate variation per binary orbit. If confirmed, M81 would be one of the closest SMBHB candidates, providing a rare opportunity to study the final parsec problem. [ABSTRACT FROM AUTHOR]

This study differentiates myocardial infarction (MI) and strangulation death (STR) from the perspective of amino acid metabolism. In this study, MI mice model via subcutaneous injection of isoproterenol and STR mice model by neck strangulation were constructed, and were randomly divided into control (CON), STR, mild MI (MMI), and severe MI (SMI) groups. The metabolomics profiles were obtained by liquid chromatography-mass spectrometry (LC–MS)-based untargeted metabolomics. Principal component analysis, partial least squares-discriminant analysis, volcano plots, and heatmap were used for discrepancy metabolomics analysis. Pathway enrichment analysis was performed and the expression of proteins related to metabolomics was detected using immunohistochemical and western blot methods. Differential metabolites and metabolite pathways were screened. In addition, we found the expression of PPM1K was significantly reduced in the MI group, but the expression of p-mTOR and p-S6K1 were significantly increased (all P < 0.05), especially in the SMI group (P < 0.01). The expression of Cyt-C was significantly increased in each group compared with the CON group, especially in the STR group (all P < 0.01), and the expression of AMPKα1 was significantly increased in the STR group (all P < 0.01). Our study for the first time revealed significant differences in amino acid metabolism between STR and MI. [ABSTRACT FROM AUTHOR]

During their formation, emerging protoplanets tidally interact with their natal disks. Proto–gas giant planets, with Hill radii larger than the disk thickness, open gaps and quench gas flow in the vicinity of their orbits. It is usually assumed that their type II migration is coupled to the viscous evolution of the disk. Although this hypothesis provides an explanation for the origin of close-in planets, it also encounters a predicament on the retention of long-period orbits for most gas giant planets. Moreover, numerical simulations indicate that the planets' migrations are not solely determined by the viscous diffusion of their natal disk. Here we carry out a series of hydrodynamic simulations combined with analytic studies to examine the transition between different paradigms of type II migration. We find a range of planetary mass for which gas continues to flow through a severely depleted gap so that the surface density distribution in the disk region beyond the gap is maintained in a quasi-steady state. The associated gap profile modifies the location of corotation and Lindblad resonances. In the proximity of the planet's orbit, high-order Lindblad and corotation torque are weakened by the gas depletion in the gap, while low-order Lindblad torques near the gap walls preserve their magnitude. Consequently, the intrinsic surface density distribution of the disk delicately determines both the pace and direction of the planets' type II migration. We show that this effect might stall the inward migration of giant planets and preserve them in disk regions where the surface density is steep. [ABSTRACT FROM AUTHOR]

This study differentiates myocardial infarction (MI) and strangulation death (STR) from the perspective of amino acid metabolism. In this study, MI mice model via subcutaneous injection of isoproterenol and STR mice model by neck strangulation were constructed, and were randomly divided into control (CON), STR, mild MI (MMI), and severe MI (SMI) groups. The metabolomics profiles were obtained by liquid chromatography-mass spectrometry (LC–MS)-based untargeted metabolomics. Principal component analysis, partial least squares-discriminant analysis, volcano plots, and heatmap were used for discrepancy metabolomics analysis. Pathway enrichment analysis was performed and the expression of proteins related to metabolomics was detected using immunohistochemical and western blot methods. Differential metabolites and metabolite pathways were screened. In addition, we found the expression of PPM1K was significantly reduced in the MI group, but the expression of p-mTOR and p-S6K1 were significantly increased (all P < 0.05), especially in the SMI group (P < 0.01). The expression of Cyt-C was significantly increased in each group compared with the CON group, especially in the STR group (all P < 0.01), and the expression of AMPKα1 was significantly increased in the STR group (all P < 0.01). Our study for the first time revealed significant differences in amino acid metabolism between STR and MI. [ABSTRACT FROM AUTHOR]

Sgr A* represents a unique laboratory for the detailed study of accretion processes around a low-luminosity supermassive black hole (SMBH). Recent X-ray observations have allowed for spatially resolved modelling of the emission from the accretion flow around the SMBH, placing tight constraints on the flux and spectral shape of the accretion from the inner region with r < 103 R g, where R g ≡ GM BH/ c 2 is the gravitational radius of the black hole of mass M BH. We present here the first modelling of the multiband spectral energy distribution (SED) of this inner region to better constrain the physical condition of the innermost accretion flow. Our modelling uses the Markov chain Monte Carlo method to fit the SED, accounting for the limitations on the accretion rate at the outer radius of 103 R g from the earlier works and the domination of the accretion flow within 30 R g to the sub-mm bump. It is found that the fitting results of the outflow index could be very different. If only the most luminous part of the SED, the sub-mm bump, is considered, the outflow index is about 0, while if low-frequency radio data and X-ray data are also included, the outflow index could be 0.37 or even higher. The great difference of the fitting results indicates that the outflow index should be variable along radius, with a strong outflow in the outer region and a weak outflow in the innermost region. Such a weak outflow agrees with numerical simulations and makes it possible to explain the multiband SED even better. [ABSTRACT FROM AUTHOR]

The interaction of chitosan and polyamines (PAs) could be involved mitigating drought stress in white clover (Trifolium repens L.). This research aimed to determine the effect of chitosan and PAs, and co-application of chitosan and PAs on improving drought tolerance associated with growth, phytohormones, polyamines and antioxidant metabolism. Plants were pretreated with or without 1 g L–1 chitosan, 0.5 mM spermine, or 1 g L–1 chitosan + 0.5 mM spermine, then subjected to drought induced by polyethylene glycol (PEG) 6000 (–0.5 MPa) in growth chambers for 14 days. Exogenous chitosan and spermine improved the level of PAs by regulating arginine decarboxylases, S -adenosyl methionine decarboxylase, copper-containing amine oxidase and polyamine oxidase activity, and expression of the genes encoding these enzymes under drought. Application of exogenous chitosan improved ABA content under normal and drought conditions. In addition, chitosan and spermine significantly enhanced the levels of cytokinin and GA, but reduced IAA levels during drought stress. Exogenous chitosan and spermine improved antioxidant defence, including enzyme activity, gene expression and the content of ascorbate and glutathione compounds, leading to a decline in superoxide anion radicals, H2O2 and malondialdehyde, effectively mitigating drought-induced oxidative damage. Other protective metabolites, such as total phenols and flavonoids, increased considerably under application of chitosan and spermine. These results suggest that chitosan-induced drought tolerance could be involved in PA metabolism, changes in endogenous phytohormones and antioxidant defence in white clover. Co-application of chitosan and spermine was more effective than either chitosan or spermine alone in mitigating drought stress. The interaction of chitosan and polyamines could be involved in mitigating drought stress in white clover. This research aimed to determine the effect of co-application of chitosan and spermine on improving drought tolerance. We found that co-application of chitosan and spermine was more effective than either chitosan or spermine alone in mitigating drought stress. Our results demonstrate the potential advantage of further studies on improving drought tolerance in white clover. [ABSTRACT FROM AUTHOR]

Sgr A* is probably the supermassive black hole being investigated most extensively due to its proximity to Earth. Several theoretical models for its steady state emission have been proposed in the past two decades. Both the radiative-inefficient accretion flow and the jet model have been shown to well explain the observed spectral energy distribution. The Faraday rotation measure (RM) has been unambiguously measured at the submillimeter wavelength, but it has only been tested against the accretion flow model. Here we first calculate the RM based on the jet model and find that the predicted value is two orders of magnitude lower than the measured value. We then include an additional contribution from the accretion flow in front of the jet and show that the measured RM may be reconciled with the model under some tight constraints. The main constraint is that the inclination angle should be greater than ∼73°. However, this requirement is not consistent with an existing observational estimate of the inclination angle. [ABSTRACT FROM AUTHOR]

The heart is the main organ of the circulatory system and requires fatty acids to maintain its activity. Stress is a contributor to aggravating cardiovascular diseases and even death, and exacerbates the abnormal lipid metabolism. The cardiac metabolism may be disturbed by stress. Cholecystokinin (CCK), which is a classical peptide hormone, and its receptor (CCKR) are expressed in myocardial cells and affect cardiovascular function. Nevertheless, under stress, the exact role of CCKR on cardiac function and cardiac metabolism is unknown and the mechanism is worth exploring. After unpredictable stress, a common stress-inducing model that induces the development of mood disorders such as anxiety and reduces motivated behavior, we found that the abnormal contraction and diastole of the heart, myocardial injury, oxidative stress and inflammation of mice were aggravated. Cholecystokinin A receptor and cholecystokinin B receptor knockout (CCK1R2R-/-) significantly reversed these changes. Mechanistically, fatty acid metabolism was found to be altered in CCK1R2R-/- mice. Differential metabolites, especially L-tryptophan, L-aspartic acid, cholesterol, taurocholic acid, ADP, oxoglutaric acid, arachidonic acid and 17-Hydroxyprogesterone, influenced cardiac function after CCK1R2R knockout and unpredictable stress. We conclude that CCK1R2R-/- ameliorated myocardial damage caused by unpredictable stress via altering fatty acid metabolism. [ABSTRACT FROM AUTHOR]

Multiclass dynamic emergency traffic consisting of evacuation and rescue vehicles is a common situation on the road network in the response of the sudden local disaster, e.g., fire disaster, hazardous chemical disaster, etc. However, there are several options for the optimal rescue traffic routes sharing the same optimum objective value during the evacuation, and it is not clear how different optimal rescue traffic routes will affect evacuation traffic. Our motivation is based on the possibility for the dynamic rescue traffic optimum to have multiple solutions on the road network shared by multiple vehicle classes, which differ in when and which roads are occupied by how many rescue vehicles during the evacuation. To this end, we formulate multiclass dynamic emergency traffic collaborative optimization problem considering multiple solutions and traffic priority as the MMILP-RRO formulation, which consists of multi-objective mixed integer linear programming formulation (MMILP) and risk-based rescue traffic optimization formulation (RRO), and is solved by a stage-based optimization algorithm. The numerical results are conducted on the Beijing's Zhongguancun​ road network to provide some insights into the effects of multiple optimal rescue traffic routes on evacuation traffic for multiclass dynamic emergency traffic network flow collaborative management. • Multiclass dynamic emergency traffic collaborative optimization with multi-solutions. • MMILP-RRO formulation with stage-based optimization algorithm. • Effect of multiple optimal rescue traffic routes considering traffic priority. [ABSTRACT FROM AUTHOR]