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Abstract Background Oral squamous cell carcinoma (OSCC) is the most common malignancy of the head and neck. Zeng-Sheng-Ping, composed of Sophora tonkinensis Gagnep., Bistorta officinalis Delarbre, Sonchus arvensis L., Prunella vulgaris L., Dioscorea bulbifera L., and Dictamnus dasycarpus Turcz., was regarded as an anti-cancer drug with significant clinical efficacy, but was discontinued due to liver toxicity. Our research group developed a modified Zeng-Sheng-Ping (ZSP-M) based on original Zeng-Sheng-Ping that exhibited high efficiency and low toxicity in preliminary investigations, although its pharmacodynamic mechanism is still unclear. Here, we aimed to elucidate the pharmacodynamic material basis of ZSP-M and investigate its chemopreventive effect on OSCC by modulating tumor associated macrophages (TAMs). Methods Components of ZSP-M were characterized using ultra-performance liquid chromatography-mass spectrometry. Chemopreventive effect induced by ZSP-M against experimental oral cancer was investigated using the 4-nitroquinoline N-oxide precancerous lesion mouse model. RNA sequencing analysis was used to gain a global transcriptional view of the effect of ZSP-M treatment. A cell co-culture model was used to study the targeted effect of ZSP-M on TAMs and the biological properties of OSCC cells and to detect changes in TAM phenotypes. The binding of ZSP-M active compounds to TNF alpha induced protein 6 (TNFAIP6) protein was analyzed by molecular docking and dynamic simulation. Results Forty main components of ZSP-M were identified, the most abundant of which were flavonoids. ZSP-M inhibited the degree of epithelial dysplasia in precancerous lesions by inhibiting the expression of the TNFAIP6 and CD163 proteins in the precancerous lesions of the tongue. ZSP-M inhibited proliferation, colony formation, migration and invasion of SCC7 cells by targeting TAMs. ZSP-M reduced the expression of CD163+ cells, inhibited the expression of TNFAIP6 protein, Arg1 mRNA and Il10 mRNA in TAMs, and reduced IL-10 cytokine release in the co-culture environment. This effect was maintained after the addition of recombinant TNFAIP6 protein. Computer simulations showed that trifolirhizin and maackiain are well-connected to TNFAIP6. Conclusions ZSP-M counteracts the immunosuppressive action of TAMs by specific targeting of TNFAIP6, thereby exerting chemopreventive activity of OSCC.

Objectives: Compromised hepatic fatty acid oxidation (FAO) has been observed in human MASH patients and animal models of MASLD/MASH. It remains poorly understood how and when the hepatic FAO pathway is suppressed during the progression of MASLD towards MASH. Hepatic ChREBP⍺ is a classical lipogenic transcription factor that responds to the intake of dietary sugars. Methods: We examined its role in regulating hepatocyte fatty acid oxidation (FAO) and the impact of hepatic Chrebpa deficiency on sensitivity to diet-induced MASLD/MASH in mice. Results: We discovered that hepatocyte ChREBP⍺ is both necessary and sufficient to maintain FAO in a cell-autonomous manner independently of its DNA-binding activity. Supplementation of synthetic PPAR⍺/δ agonist is sufficient to restore FAO in Chrebp−/− primary mouse hepatocytes. Hepatic ChREBP⍺ was decreased in mouse models of diet-induced MAFSLD/MASH and in patients with MASH. Hepatocyte-specific Chrebp⍺ knockout impaired FAO, aggravated liver steatosis and inflammation, leading to early-onset fibrosis in response to diet-induced MASH. Conversely, liver overexpression of ChREBP⍺-WT or its non-lipogenic mutant enhanced FAO, reduced lipid deposition, and alleviated liver injury, inflammation, and fibrosis. RNA-seq analysis identified the CYP450 epoxygenase (CYP2C50) pathway of arachidonic acid metabolism as a novel target of ChREBP⍺. Over-expression of CYP2C50 partially restores hepatic FAO in primary hepatocytes with Chrebp⍺ deficiency and attenuates preexisting MASH in the livers of hepatocyte-specific Chrebp⍺-deleted mice. Conclusions: Our findings support the protective role of hepatocyte ChREBPa against diet-induced MASLD/MASH in mouse models in part via promoting CYP2C50-driven FAO.

Abstract HBV-miR-3 is encoded by HBV and takes part in pathogenesis of HBV-related liver disease. Whether HBV-miR-3 has a relationship with HBV replication and is predictive of PegIFN-α treatment response is still unknown. HBV-miR-3 quantification is based on qRT-PCR. The relationship of HBV-miR-3 and HBV replication, and predictive value of HBV-miR-3 were evaluated in a cohort of 650 HBeAg positive patients from a multi-center, randomized phase III clinical trial for the study of PegIFN-a2b. HBV-miR-3 is significantly positively related to HBVDNA, HBVpgRNA, HBeAg and HBsAg at baseline and at all the different time points during PegIFN-α treatment. Both univariate regression analyses and multivariate logistic regression analyses showed HBV-miR-3 is a predictor of HBeAg seroconversion in the patients treated with PegIFN-α at weeks of 0, 12, and 24. 70.0% of patients with HBV-miR-3 6log at week 12 no patient obtained HBeAg seroconversion. Conbination of HBV-miR-3 and HBeAg is more strongly predictive of HBeAg seroconversion (83.64%) at week 12. HBV-miR-3 is new biomarker for HBV replication and positively correlated to HBV replication. HBV-miR-3 is also an early predictor of HBeAg seroconversion in the patients treated with PegIFN-α.

Neurodevelopmental disorder with or without autistic features and/or structural brain abnormalities (NEDASB) is a rare autosomal dominant disorder caused by a heterozygous mutation in the NOVA2 gene on chromosome 19q13. Here, we describe the generation and characterization of an iPSC line derived from the peripheral blood of a 7-year-old patient carrying a novel heterozygous mutation in NOVA2 (c.625 del). The iPSCs with the confirmed patient-specific mutation were demonstrated by pluripotency markers, a normal karyotype, and the ability to differentiate into three germ layers. This NOVA2-mutant iPSC line could facilitate disease modeling and therapy development studies for NEDASB.

Abstract Background Progressive reduction of sodium intake is an attractive approach for addressing excessive salt intake, but evidence for this strategy in real practice is limited. We aimed to determine the feasibility, effectiveness, and safety of a progressive sodium intake reduction intervention in real-world setting. Methods We randomized 48 residential elderly care facilities in China, with 1612 participants aged 55 years and older, to either progressive reduction (PR, 24 facilities) or no reduction (NR, 24 facilities) of the supply of study salt to the kitchens of these facilities for 2 years. The primary efficacy outcome was systolic blood pressure (SBP) at any scheduled follow-up visit. Secondary efficacy outcomes included diastolic blood pressure (DBP) at any scheduled follow-up visit, and major adverse cardiovascular events (comprising non-fatal stroke, non-fatal myocardial infarction, hospitalized non-fatal heart failure, or vascular death) and total mortality. The perception of food saltiness, the addition of out-of-study salt in meals, and 24-h urinary sodium excretion were used as process indicators. Results Pre-specified analysis per randomization found no effect of the intervention on the 2-year overall mean systolic and diastolic blood pressure (SBP, DBP) and any other outcomes. However, post hoc analysis showed that the intervention effect on blood pressure varied over multiple follow-up visits (p for interaction

Background: Neurodevelopmental disorders (NDDs) are a group of diseases that severely affect the physical and mental health of children. The PPP2R5D gene encodes B56δ, the regulatory subunit of protein phosphatase 2A (PP2A). NDDs related to the PPP2R5D gene have recently been defined as Houge–Janssens syndrome 1. Methods: Clinical/whole exome sequencing was performed on approximately 3000 patients with NDDs from 2017 to 2023. In vitro experiments were performed to assess the impairment of variants to protein expression and the assembly of PP2A holoenzyme. The genetic information and phenotypes of the reported patients, as well as patients in this study, were summarized, and the genotype–phenotype relationship was analyzed. The probability of pathogenic missense variants in PPP2R5D was predicted using AlphaMissense (AM), and the relationship between certain phenotype and 3D protein structural features were analyzed. Results: Thirteen new patients carrying twelve PPP2R5D gene variants were detected, including five novel missense variants and one novel frameshift variant. In vitro experiments revealed that the frameshift variant p.H463Mfs*3 resulted in a ~50 kDa truncated protein with lower expression level. Except for E420K and T536R, other missense variants impaired holoenzyme assembly. Furthermore, we found that pathogenic/likely pathogenic (P/LP) variants that have been reported so far were all missense variants and clustered in three conserved regions, and the likelihood of P/LP mutations located in these conserved regions was extremely high. In addition, the macrocephaly phenotype was related to negatively charged residues involved in substrate recruitment. Conclusions: We reported thirteen new patients with PPP2R5D gene variants and expanded the PPP2R5D variant spectrum. We confirmed the pathogenicity of novel variants through in vitro experiments. Our findings in genotype–phenotype relationship provide inspiration for genetic counseling and interpretation of variants. We also provide directions for further research on the mechanism of macrocephaly phenotype.

Five degraded products of limonoid, including two previously undescribed compounds (1, 3) and one pair of new natural products (4i, 4ii), were isolated from the root bark of Dictamnus dasycarpus Turcz. Their structures were elucidated by extensively spectroscopic methods (NMR, MS, ECD, etc), as well as quantum chemical calculations. The broadening NMR lines, along with the relaxation time and DOSY experiment revealed the self-aggregation of 1 in chloroform through H-bond between –COOH and –OH, which provided additional evidence to distinguish acid and ester/lactone in structure elucidation. Compounds 1–3 attenuated oleic acid-induced lipid accumulation in HepG2 cells significantly, with inhibition rates of 19.8%, 23.6%, and 13.5% at 10 μM, much stronger than fenofibrate, affording a novel scaffold for drug discovery against fatty liver disease.

Background:Penthorum chinense Pursh (PCP) is widely utilized in China to treat a variety of liver diseases. It has been shown that flavonoids inhibit inflammation and have the potential to attenuate tissue damage and fibrosis. However, the mechanisms underlying how total flavonoids isolated from PCP (TFPCP) exert their anti-fibrotic effects remain unclear.Methods: The chemical composition of TFPCP was determined using UHPLC–Q-Orbitrap HRMS. Subsequently, rats were randomly assigned to a control group (Control), a carbon tetrachloride (CCl4)-induced hepatic fibrosis model group (Model), a positive control group [0.2 mg/(kg∙day)] of Colchicine), and three TFPCP treatment groups [50, 100, and 150 mg/(kg∙day)]. All substances were administered by gavage and treatments lasted for 9 weeks. Simultaneously, rats were intraperitoneally injected with 10%–20% CCl4 for 9 weeks to induce liver fibrosis. At the end of the experiment, the liver ultrasound, liver histomorphological, biochemical indicators, and inflammatory cytokine levels were tested respectively. The underlying mechanisms were assessed using Western blot, immunohistochemistry, immunofluorescence, RT-qPCR, and metabolomics.Results: Fourteen flavonoids were identified in TFPCP. Compared with control animals, CCl4-treated rats demonstrated obvious liver injury and fibrosis, manifested as increases in gray values, distal diameter of portal vein (DDPV) and a decrease in blood flow velocity (VPV) in the ultrasound analysis; increased biochemical index values (serum levels of ALT, AST, TBIL, and ALP); marked increases in the contents of fibrotic markers (PC III, COL4, LN, HA) and inflammatory factors (serum TNF-α, IL-6, and IL-1β); and significant pathological changes. However, compared with the Model group, the ultrasound parameters were significantly improved and the serum levels of inflammatory cytokines were reduced in the TFPCP group. In contrast, the expression of TGF-β1, TLR4, and MyD88, as well as the p-P65/P65 and p-IκBα/IκBα ratios, were considerably reduced following TFPCP treatment. In addition, we identified 32 metabolites exhibiting differential abundance in the Model group. Interestingly, TFPCP treatment resulted in the restoration of the levels of 20 of these metabolites.Conclusion: Our findings indicated that TFPCP can ameliorate hepatic fibrosis by improving liver function and morphology via the inactivation of the TLR4/MyD88-mediated NF-κB pathway and the regulation of liver metabolism.

BackgroundCerebral palsy (CP) is a neurodevelopmental disorder characterized by motor impairment. In this study, we aimed to describe the characteristics of amino acids (AA) in the plasma of children with CP and identify AA that could play a potential role in the auxiliary diagnosis and treatment of CP.MethodsUsing high performance liquid chromatography, we performed metabolomics analysis of AA in plasma from 62 CP children and 60 healthy controls. Univariate and multivariate analyses were then applied to characterize different AA. AA markers associated with CP were then identified by machine learning based on the Lasso regression model for the validation of intra-sample interactions. Next, we calculated a discriminant formula and generated a receiver operating characteristic (ROC) curve based on the marker combination in the discriminant diagnostic model.ResultsA total of 33 AA were detected in the plasma of CP children and controls. Compared with controls, 5, 7, and 10 different AA were identified in total participants, premature infants, and full-term infants, respectively. Of these, β-amino-isobutyric acid [p = 2.9*10(−4), Fold change (FC) = 0.76, Variable importance of protection (VIP) = 1.75], tryptophan [p = 5.4*10(−4), FC = 0.87, VIP = 2.22], and asparagine [p = 3.6*10(−3), FC = 0.82, VIP = 1.64], were significantly lower in the three groups of CP patients than that in controls. The combination of β-amino-isobutyric acid, tryptophan, and taurine, provided high levels of diagnostic classification and risk prediction efficacy for preterm children with an area under the curve (AUC) value of 0.8741 [95% confidence interval (CI): 0.7322–1.000]. The discriminant diagnostic formula for preterm infant with CP based on the potential marker combination was defined by p = 1/(1 + e−(8.295–0.3848* BAIBA-0.1120*Trp + 0.0108*Tau)).ConclusionFull-spectrum analysis of amino acid metabolomics revealed a distinct profile in CP, including reductions in the levels of β-amino-isobutyric acid, tryptophan, and taurine. Our findings shed new light on the pathogenesis and diagnosis of premature infants with CP.

Neurodevelopmental disorders (NDDs) have heterogeneity in both clinical characteristics and genetic factors. EBF3 is a recently discovered gene associated with a syndromic form of NDDs characterized by hypotonia, ataxia and facial features. In this study, we report twelve unrelated individuals with EBF3 variants using next-generation sequencing. Five missense variants (four novel variants and one known variant) and seven copy number variations (CNVs) of EBF3 gene were identified. All of these patients exhibited developmental delay/intellectual disability. Ataxia was observed in 33% (6/9) of the patients, and abnormal muscle tone was observed in 55% (6/11) of the patients. Aberrant MRI reports were noted in 64% (7/11) of the patients. Four novel missense variants were all located in the DNA-binding domain. The pathogenicity of these variants was validated by in vitro experiments. We found that the subcellular protein localization of the R152C and F211L mutants was changed, and the distribution pattern of the R163G mutant was changed from even to granular. Luciferase assay results showed that the four EBF3 mutants' transcriptional activities were all significantly decreased (p

Acetaminophen (N‐acetyl‐para‐aminophenol [APAP]) overdose is the most common cause of drug‐induced liver injury in the Western world and has limited therapeutic options. As an important dietary component intake, fructose is mainly metabolized in liver, but its impact on APAP‐induced liver injury is not well established. We aimed to examine whether fructose supplementation could protect against APAP‐induced hepatotoxicity and to determine potential fructose‐sensitive intracellular mediators. We found that both high‐fructose diet feeding before APAP injection and fructose gavage after APAP injection reduced APAP‐induced liver injury with a concomitant induction of the hepatic carbohydrate‐response element‐binding protein α (ChREBPα)–fibroblast growth factor 21 (FGF21) pathway. In contrast, Chrebpα liver‐specific‐knockout (Chrebpα‐LKO) mice failed to respond to fructose following APAP overdose, suggesting that ChREBPα is the essential intracellular mediator of fructose‐induced hepatoprotective action. Primary mouse hepatocytes with deletion of Fgf21 also failed to show fructose protection against APAP hepatotoxicity. Furthermore, overexpression of FGF21 in the liver was sufficient to reverse liver toxicity in APAP‐injected Chrebpα‐LKO mice. Conclusion: Fructose protects against APAP‐induced hepatotoxicity likely through its ability to activate the hepatocyte ChREBPα–FGF21 axis.

BackgroundThere are estimated 20% of mechanically ventilated patients having difficulty in weaning from the ventilators, and the weaning process accounts for 40% of the whole ventilation time. Reliable tools are urgently needed to estimate the weaning outcome. Diaphragmatic ultrasonography, as a relatively good predictive method for the adults, was measured in this study, assessing the value of each indicator of diaphragmatic ultrasonography to predict the outcomes of ventilator weaning from mechanically ventilated children of 1–3 years old.MethodsBetween November 2018 and November 2019, children who were mechanically ventilated and ready for weaning in the pediatric intensive care unit (PICU) were enrolled in the study. Diaphragmatic ultrasonography was performed to the children to measure the right diaphragm excursion (DE), contraction velocity, thickness, and diaphragm thickening fraction (DTF), which were recorded followed by spontaneous breathing trial (SBT). The receiver operator characteristic (ROC) curves were also used to assess the value of each indicator to predict the weaning outcome.ResultsDuring this study period, a total of 72 children were enrolled, and of them, 56 children passed the weaning process, while 16 children failed. There were significant differences in DE, contraction velocity, thickness, and DTF parameters between the weaning success group and the failure group. The areas under the ROC curves (AUC) and the optimal threshold of the above indicators were as follows: 0.72 and 8.08 mm for DE, 0.71 and 26.1% for right DTF (DTFR), 0.71 and 20.7% for left DTF (DTFL), 0.78 and 14.8% for minimum DTF (DTFMIN), 0.79 and 26.1% for maximum DTF (DTFMAX), 0.71 and 1.24 mm for maximum diaphragm thickness at the end of inspiration (DteiMAX), and 0.65 and 10.0 mm/s for contraction velocity.ConclusionDiaphragmatic ultrasonography is feasible in guiding ventilator weaning, and the indicators of DE, DTF, and DteiMAX guide the weaning more accurately. Among them, DTF may act as a more reliable predictor of weaning by avoiding the influence of diaphragm development in children.

Abstract Background Intellectual disability (ID) constitutes the most common group of neurodevelopmental disorders. Exome sequencing has enabled the discovery of genetic mutations responsible for a wide range of ID disorders. Case presentation In this study, we reported on two male siblings, aged 4 and 2 years, with motor and mental developmental delays and mild dysmorphic facial features. To identify the genetic causes of these symptoms, we employed trio-whole exome sequencing for the proband. We found a novel hemizygous missense variant in the PAK3 gene (c.1112G > A, p.Cys371Tyr), which encodes the p21-activated kinase 3, in the proband, which inherited from mother. The younger brother also has the hemizygous variant, which was confirmed by Sanger sequencing. The variant is located in the kinase domain and was regarded as a likely pathogenic variant in this family. Conclusion We diagnosed two male siblings with developmental delays as having a PAK3 likely pathogenic variant. This finding expands the list of PAK3 gene mutations associated with neurodevelopmental disorders and provides further details on its clinical features.

Noninvasive assessment of severity of liver fibrosis is crucial for understanding histology and making decisions on antiviral treatment for chronic HBV in view of the associated risks of biopsy. We aimed to develop a computer-assisted assessment system for the evaluation of liver disease severity by using machine leaning classifier based on physical-layer with serum markers. The retrospective data set, including 920 patients, was used to establish Decision Tree Classifier (DTC), Random Forest Classifier (RFC), Logistic Regression Classifier (LRC), and Support Vector Classifier (SVC) for liver fibrosis severity assessment. Training and testing samples account for 50% of the data set, respectively. The best indicator combinations were selected in random combinations of 24 indicators including 67 108 760 group indicators by four different machine learning classifiers. The resulting classifiers prospectively tested in 50% testing patients, and the sensitivity, specificity, overall accuracy, and receiver operating characteristics (ROC) were used to compare four classifiers to existed 19 models. Results show that the RFC-based classifier system, with 9 indicators, is feasible to assess severity for liver fibrosis with diagnostic accuracy (greater than 0.83) superior to existing 19 models. Additional studies based on a large data set with full serum markers and imaging information are necessary to enhance diagnostic accuracy and to expand clinical application.

Metal–organic frameworks with highly ordered porosity have been studied extensively. In this paper, the effect of framework (pore) disorder on the gas sorption of azole-based isoreticular Cu(II) MOFs with rtl topology and characteristic 1D tubular pore channels is investigated for the first time. In contrast to other isoreticular rtl metal–organic frameworks, the Cu(II) metal–organic framework based on 5-(1H-imidazol-1-yl)isophthalate acid has a crystallographically identifiable disordered framework without open N-donor sites. The framework provides a unique example for investigating the effect of pore disorder on gas sorption that can be systematically evaluated. It exhibits remarkable temperature-dependent hysteretic CO2 sorption up to room temperature, and shows selectivity of CO2 over H2, CH4 and N2 at ambient temperature. The unique property of the framework is its disordered structure featuring distorted 1D tubular channels and DMF-guest-remediated defects. The results imply that structural disorder (defects) may play an important role in the modification of the performance of the material.

Global crises have created unprecedented challenges for communities and economies across the world, triggering turmoil in global finance and economy. This study adopts the dynamic conditional correlation multiple generalized autoregressive conditional heteroskedasticity (DCC–MGARCH) model to explore contagion effects across financial markets in crisis. The main findings are as follows: (1) the financial crisis and COVID-19 pandemic intensified the connection between the Chinese and US stock markets in the short term; (2) the dynamic conditional correlations (DCCs) during the COVID-19 pandemic are higher than those during the 2008 financial crisis owing to the further opening of the Chinese capital market, and financial institutions’ investments in the European market are higher than those in the American markets; (3) a stepwise increase is observed in the dynamic conditional correlation between the returns on the S&P 500 Index and SSEC during and after the onset of a destructive crisis; and (4) a unidirectional contagion effect exists between the Chinese market and US market, and the Hong Kong stock market contributes to the risk spillover. Effective transmission channels of external negative shocks may be investors’ sentiments, financial institutions, and the RMB exchange rate in the stock markets. This study provides useful suggestions to authorities formulating financial regulations and investors diversifying risk investments.

Fraxinellone (FRA), a major active component from Cortex Dictamni, produces hepatotoxicity via the metabolization of furan rings by CYP450. However, the mechanism underlying the hepatotoxicity of FRA remains unclear. Therefore, zebrafish larvae at 72 h post fertilization were used to evaluate the metabolic hepatotoxicity of FRA and to explore the underlying molecular mechanisms. The results showed that FRA (10–30 μM) induced liver injury and obvious alterations in the metabolomics of zebrafish larvae. FRA induces apoptosis by increasing the level of ROS and activating the JNK/P53 pathway. In addition, FRA can induce cholestasis by down-regulating bile acid transporters P-gp, Bsep, and Ntcp. The addition of the CYP3A inhibitor ketoconazole (1 μM) significantly reduced the hepatotoxicity of FRA (30 μM), which indicated that FRA induced hepatotoxicity through CYP3A metabolism. Targeted metabolomics analysis indicates the changes in amino acid levels can be combined with molecular biology to clarify the mechanism of hepatotoxicity induced by FRA, and amino acid metabolism monitoring may provide a new method for the prevention and treatment of DILI from FRA.

The visible and infrared scanning radiometer (VIRR) onboard the Fengyun-3C (FY-3C) meteorological satellite has 11 μm and 12 μm channels, which are capable of sea surface temperature (SST) observations. This study is based on atmospheric radiative transfer modeling (RTM) by applying Bayesian cloud detection theory and optimal estimation (OE) to obtain sea surface skin temperature (SSTskin) from VIRR in the Northwest Pacific. The inter-calibration of FY-3C/VIRR 11 μm and 12 μm brightness temperature (BT) is carried out using the Moderate Resolution Imaging Spectroradiometer (MODIS) as the reference sensor. Bayesian cloud detection and OE SST retrieval with the calibration BT data is performed to obtain SSTskin. The SSTskin retrievals are compared with the buoy SST with a temporal window of 1 h and a spatial window of 0.01°. The bias is −0.12 °C, and the standard deviation is 0.52 °C. Comparisons of the retrieved SSTskin with the AVHRR (Advanced Very High Resolution Radiometer) SSTskin from European Space Agency Sea Surface Temperature Climate Change Initiative (ESA SST CCI) project show the bias of 0.08 °C and the standard deviation of 0.55 °C. The results indicate that the VIRR SSTskin are consistent with AVHRR SSTskin and buoy SST.

Wild animals are vulnerable to environmental noise. In wetlands, wintering waterbirds are easily disturbed by ship noises; however, the behavioral changes of waterbirds in response to different levels of noise are unclear. We simulated the acoustic environment created by ship movement to investigate the effects of ship noise on foraging, vigilance, and flight behaviors of the wintering bean goose (Anser fabalis). In particular, we used a noise playback method to simulate the acoustic environment created by ship operations at various noise levels (i.e., background noise N ≤ 30) were more sensitive to noise interference. As the noise level increased, the frequency of foraging behavior decreased and the frequencies of vigilance and flight behaviors increased, particularly above 70 dB. For noises >70 dB at short disturbance distances and >80 dB at medium disturbance distances, flight behavior increased significantly. These findings suggested that ships should keep a distance of more than 200 m from waterbirds to reduce noise interference.

Increasing arsenic (As) pollution is posing potential endangerment to mangrove wetland ecosystems. Mangrove phytoextraction, translocation, and responses to As exposure must be urgently addressed. In this study, the growth and physiological response of Kandelia obovata seedlings were examined after addition of 25−200 mg kg−1 As under sediment culture conditions. Results showed that the seedling morphological variations were not significant below 100 mg kg−1 compared to the control group, indicating superoxide dismutase, peroxidase, and catalase synergetic interaction to resist the As exposure. High As concentrations (150–200 mg kg−1) inhibited the seedling growth accompanied by a significant increase in malondialdehyde content and decrease in activities of antioxidant enzymes. Toxicity symptoms and mortality appeared in 200 mg kg−1 As, presumably because the plant reached the limit of As tolerance. Besides, As accumulated mainly in roots, accounting for 87.04–97.85% of the total As, and the bioaccumulation factor (BCF) was >100%. However, the BCF and translocation factor (TF) in stems and leaves were below unity, illustrating a weak capacity of transferring As to aerial parts of the seedlings. Overall, K. obovata is a potential remediated species in polluted coastal wetlands due to high phytoextraction capacity and high tolerance to As exposure.

Fengyun-3C (FY-3C) is a second-generation meteorological satellite of China that was launched on 23 September 2013. The on board Visible and Infrared Radiometer (VIRR) can be used to observe global sea surface temperature (SST). In this paper, the VIRR SST products are compared with MODIS SST products and buoy measurements from 2015 to 2019. The collocations of VIRR, MODIS, and buoy SST are generated separately during the day and night with the spatial window of 0.05° × 0.05°. The comparison results show that the biases of VIRR SST minus buoy SST during the day and night are −0.21 and −0.13 °C with a corresponding robust standard deviation (RSD) of 0.58 and 0.59 °C, respectively. The mean differences between VIRR and MODIS are −0.10 and 0.08 °C with RSDs of 0.53 and 0.58 °C for the daytime and nighttime, respectively. The consistency of VIRR SST accuracy from 2015 to 2019 and the dependence of VIRR SST error on SST and latitude are also investigated.

Material properties affect the surface finishing in ultra-precision diamond cutting (UPDC), especially for aluminum alloy 6061 (Al6061) in which the cutting-induced temperature rise generates different types of precipitates on the machined surface. The precipitates generation not only changes the material properties but also induces imperfections on the generated surface, therefore increasing surface roughness for Al6061 in UPDC. To investigate precipitate effect so as to make a more precise control for the surface quality of the diamond turned Al6061, it is necessary to confirm the compositions and material properties of the precipitates. Previous studies have indicated that the major precipitate that induces scratch marks on the diamond turned Al6061 is an AlFeSi phase with the composition of Al86.1Fe8.3Si5.6. Therefore, in this paper, to study the material properties of the AlFeSi phase and its influences on ultra-precision machining of Al6061, an elastoplastic-damage model is proposed to build an elastoplastic constitutive model and a damage failure constitutive model of Al86.1Fe8.3Si5.6. By integrating finite element (FE) simulation and JMatPro, an efficient method is proposed to confirm the physical and thermophysical properties, temperature-phase transition characteristics, as well as the stress–strain curves of Al86.1Fe8.3Si5.6. Based on the developed elastoplastic-damage parameters of Al86.1Fe8.3Si5.6, FE simulations of the scratch test for Al86.1Fe8.3Si5.6 are conducted to verify the developed elastoplastic-damage model. Al86.1Fe8.3Si5.6 is prepared and scratch test experiments are carried out to compare with the simulation results, which indicated that, the simulation results agree well with those from scratch tests and the deviation of the scratch force in X-axis direction is less than 6.5%.

Aluminum alloy 6061(Al6061), an Al-Mg-Si alloy, is a precipitation-hardened alloy. The generation of precipitate affects its mechanical properties, and induces a worse surface finish during diamond cutting. The friction coefficients of the tool-chip and tool-workpiece interfaces influence temperature rise, and are therefore important predictors of tool wear and surface integrity during the diamond cutting of Al6061. This study investigated the relationship between precipitate generation and the friction coefficients of Al6061. Groups of experiments were conducted to study the influence of temperature and heating time on the number of precipitates and the friction coefficients. The results show that the generation of AlFeSi particles induces cracks, scratch marks and pits on diamond-machined Al6061 and affects the cutting forces. Moreover, the variation trend of the friction coefficient of Al6061 under different heating conditions agrees well with that of the number of AlFeSi particles. This implies that, during ultra-precision machining of precipitation-hardened alloys, cutting-induced heat causes precipitates to form on the chips and machined surface, changing their material properties. This affects the tool-workpiece and tool−chip contact conditions and the mechanisms of chip formation and surface generation in ultra-precision machining.

Eight new 9,10-anthraquinones (1–8) including three acetonide derivatives of 3-hydroxy-2-hydroxymethyl-9,10-anthraquinones (6–8) were isolated from an ethanol extract of the roots of Knoxia valerianoides. On the basis of chemical transformation reactions of the co-occurring 14 and 15 combined with HPLC–DAD–ESI–MS analysis of the extracts, the previously and newly isolated 2-methoxymethyl- and 2-ethoxymethyl-9,10-anthraquinones (4, 5, and 9–13), as well as the 3-hydroxy-2-hydroxymethyl-9,10-anthraquinone acetonide derivatives (6–8), were shown to be solvolytic artifacts. In the in vitro assays, compound 4 was active to protect hepatocyte (WB-F344) damage.

Titanium alloys get wider applications in different areas due to its excellent mechanical properties. However, poor thermal conductivity and low elastic module of titanium alloy induce high tool wear and make it being one of hard-to-machine materials; especially the segmented chip formation accelerates the diamond tool wear in ultra-precision machining (UPM) of precision parts. This study applies micro-structured surface to improve machinability of titanium alloys in UPM by reducing the chip segmentation induced cutting forces fluctuations. Finite element (FE) model is built to study chip formation mechanism and characterize geometries of segmented chips in orthogonal diamond cutting of Ti6Al4V alloy with the aims at the design of micro-structures array. Turning experiments are conducted to compare cutting force, surface roughness, and tool wear for diamond turning of Ti6Al4V alloy on smooth surface and micro-structured surface. The results show that the FE simulated saw chips agree well with the measured ones. Moreover, the micro-structured surface helps to decrease cutting force, reduce diamond tool wear, and improve surface quality for UPM of titanium alloy. Especially, the new method fabricates micro-grooves array on the machined surface in half-finishing process of UPM without the need of any material pre-processing and extra manufacturing equipment, which can also provide the guidance for efficient and sustainable UPM of titanium alloys parts with high surface quality. [ABSTRACT FROM AUTHOR]

Novel hyperbranched co-polymers HP1-HP4 with twisted acene units and truxene groups have been synthesised through Suzuki coupling reaction and characterised. Single crystal analyses showed that the model compounds 3 and 5 had twisted structures with torsion angles of 40.73° and 28.65°, respectively. The polymers show blue light emission in organic solvents and thin films, as well as high stability, which might be utilised as potential candidates for organic electronic materials. [ABSTRACT FROM AUTHOR]

A charge-separated metal--organic framework (MOF) has been successfully synthesized from an imidazolium tricarboxylate ligand, N-(3,5- dicarboxylphenyl)-N'-(4-carboxylbenzyl)imidazolium chloride (DCPCBImH3Cl), and a zinc(II) dimeric secondary building unit, namely, DCPCBim-MOF-Zn, which shows an unprecedented 3,6-connected two-dimensional net topology with the point (Schlafli) symbol (4².6)2(44.69.8²). The framework contains onedimensional highly polar channels, and density functional theory calculations show that positive charges are located on the imidazolium/phenyl rings and negative charges on the carboxylate moieties. The charge-separated nature of the pore surface has a profound effect in their adsorption behavior, resulting in remarkable hysteretic sorption of various gases and vapors. For CO2the hysteretic sorption was observed to occur even up to 298 K. Additionally, trace chloride anions present in the pore channels are able to modulate the gas-sorption behavior. [ABSTRACT FROM AUTHOR]

A structurally flexible porous metal–organic framework, [CuII(bped)2(H2O)2(SiF6)] ⊃ 4H2O (Cu-MOF-SiF6) was prepared from CuSiF6and meso-1,2-bis(4-pyridyl)-1,2-ethanediol (bped) in EtOH–H2O. Cu-MOF-SiF6is a three-dimensional (3D) polycatenated framework consisting of two-dimensional (2D) (4,4) topological grid networks which display 2-fold inclined interpenetration in the crystal lattice. The SiF62−anions hosted in the one-dimensional channels of Cu-MOF-SiF6can be readily exchanged with NO3−anions while keeping the framework intact, leading to isomorphous Cu-MOF-NO3. The Cu-MOFs show selective adsorption behaviors due to the host–guest interaction, which is dependent on the anions and the guest size. The MeOH uptake investigation indicates that Cu-MOF-SiF6demonstrates a breathing effect, while Cu-MOF-NO3exhibits distinctive stepwise MeOH sorption due to the smaller size of NO3−and the larger voids in the crystal lattice. Cu-MOF-NO3also exhibits stepwise sorption for larger EtOH guests, while the uptake of EtOH is blocked in Cu-MOF-SiF6. In addition, the solids show anion-responsive catalytic properties. Both Cu-MOF-SiF6and Cu-MOF-NO3efficiently oxidize benzylic compounds to the corresponding carbonyl functionality under mild and convenient reaction conditions, but improved catalytic activity was observed for Cu-MOF-NO3. The catalysts can be reused with the framework left intact at least three times without losing of any activity. [ABSTRACT FROM AUTHOR]

In ultra-precision machining, the heating effect on a workpiece induced by cutting process itself plays an important role in the machining process as it affects tool life, machining accuracy, and the surface quality of the workpiece. This paper discusses the cutting-induced heating effect in ultra-precision raster milling based on the study of the time-temperature-dependent precipitation of 6061 aluminum alloy. Experiments are designed to estimate the temperature variation of the workpiece in ultra-precision machining by comparing the change in the size of precipitates in isothermal heat treatment with those in raster milling process under different depth of cut. Microscopical examination under a scanning electron microscope (SEM) revealed that the temperature on the raster-milled surface is much higher than 500°C. In the last part of this paper, the heat generation of the workpiece in the process of ultra-precision raster milling is simulated by finite element method, the result of which is found to be consistent with that from SEM. [ABSTRACT FROM AUTHOR]