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This study examines the potential impacts of projected atmospheric carbon dioxide (pCO2) levels reaching 800 ppm by the end of the century, focusing on ocean acidification effects onmarine ecosystems in the coastal areas of Bohai.We investigated how acidification affects the grazing patterns of microzooplankton using dilution techniques and ecophysiological methods. Our findings indicate that acidic conditions shift the phytoplankton community structure, changing dominant species. Elevated CO2 concentrations reduced grazing pressure on phytoplankton, with less steep declines in growth rates at 800 ppm CO² (spring: 2.43 d-1 vs. 2.16 d-1, summer: -0.46 d-1 vs. -0.73 d-1, autumn: -0.45 d-1 vs. -0.90 d-1) and significant decreases in grazing pressure percentages (%Pp from 0.84 to 0.58 and %Pi from 0.64 to 0.46). Short-term acid exposure significantly increased superoxide dismutase activity in both microplankton (from 0.03 to 0.08 U mg-1, p<0.01) and nanoplankton (from 0.05 to 0.09 U mg-1, p<0.001), indicating an adaptive response to oxidative stress. These results highlight that elevated CO2 levels primarily boost phytoplankton growth by reducing microzooplankton grazing pressure, resulting in higher growth rates and a shift towards smallersized phytoplankton, reflecting complex short-term ecological responses to acidification. Further research is needed to understand the long-term effects of ocean acidification on microzooplankton and their role in marine secondary productivity. [ABSTRACT FROM AUTHOR]

Sulfated polysaccharides (SPs) isolated from seaweed have emerged as remarkable bioactive compounds with a wide spectrum of biological activities and have substantial value in the scientific and industrial domains. The current study explores the diverse biological activities of SPs and their relationship with their structures. This aids in an in-depth examination of the multifaceted biological activities of SPs, including anticoagulant, anti-inflammatory, antiviral, antioxidant, and immunomodulatory properties, which underpin their potential health benefits. Furthermore, the current study explores the complicated properties of SPs, with their extraction methodologies and techniques for precise characterization. Elucidation of the commercial significance of SPs derived from brown, red, and green seaweed by highlighting their potential applications has emphasized their importance in human well-being. Further, this review emphasizes the challenges needed to overcome research and industrial innovations for SPs. Collaboration among researchers, industry stakeholders, and regulatory authorities can overcome these challenges and elevate the potential of SPs to revolutionize industries such as pharmaceuticals, cosmeceuticals, food, and biotechnology. [ABSTRACT FROM AUTHOR]

The uncertainty theory was founded by Baoding Liu to characterize uncertainty information represented by humans. Basing on uncertainty theory, Yuhan Liu created chance theory to describe the complex phenomenon, in which human uncertainty and random phenomenon coexist. In this paper, our aim is to derive some laws of large numbers (LLNs) for uncertain random variables. The first theorem proved the Etemadi type LLN for uncertain random variables being functions of pairwise independent and identically distributed random variables and uncertain variables without satisfying the conditions of regular, independent and identically distributed (IID). Two kinds of Marcinkiewicz-Zygmund type LLNs for uncertain random variables were established in the case of p=(0,1) by the second theorem, and in the case of p>1 by the third theorem, respectively. For better illustrating of LLNs for uncertain random variables, some examples were stated and explained. Compared with the existed theorems of LLNs for uncertain random variables, our theorems are the generalised results. [ABSTRACT FROM AUTHOR]

To complement our previous discovery of the young snake-like structure in the solar neighbourhood and reveal the structure's full extent, we build two samples of stars within the Snake and its surrounding territory from Gaia Early Data Release 3 (EDR3). With the friends-of-friends algorithm, we identify 2694 and 9052 Snake member candidates from the two samples. 13 open clusters are embedded in these member candidates. By combining the spectroscopic data from multiple surveys, we investigate the comprehensive properties of the candidates and find that they are very likely to belong to one sizable structure, since most of the components are well bridged in their spatial distributions, and follow a single stellar population with an age of 30–40 Myr and solar metallicity. This sizable structure is best explained as hierarchically primordial, and probably formed from a filamentary giant molecular cloud with unique formation history in localized regions. To analyse the dynamics of the Snake, we divide the structure into four groups according to their tangential velocities. We detect anisotropic expansion rates of the groups along different axes, and find that the average expansion age (⁠|$\bar{\tau }\simeq 33$|  Myr) is highly consistent with the age of the Snake along the length of the structure (X -direction). With over 10 000 member stars, the Snake is an ideal laboratory to study nearby coeval stellar formation, stellar physics, and environmental evolution over a large spatial extent. [ABSTRACT FROM AUTHOR]

The compatibility of polyether block amide (PEBA) and polyurethane (PU) was investigated with the calculation of their Flory–Huggins interaction parameter. The results showed that PEBA and PU are compatible at different content of PEBA. Then, PEBA–PU blend membranes were prepared. Scanning electron microscopic characterization showed that the blend membranes were dense and applicable for pervaporation. The swelling degree of the blend membrane increased with the phenol concentration, which suggested that the blend membrane has preferential permeation for phenol. Pervaporation experiments showed that the separation factor of blend membranes had been enhanced. When the blend membrane with 50 wt% PEBA content is used to separate 0.1 wt% phenol aqueous solutions at 308.15 K, the separation factor (phenol to water) is 9.7 and the permeation flux is 84.1 g m–2 h–1. [ABSTRACT FROM AUTHOR]

Tumor angiogenesis provides essential nutrients and oxygen to the tumor microenvironment, which is important in tumor growth, progression and metastasis. Inhibition of tumor angiogenesis represents one of the most promising strategies in tumor therapy. The authors previously demonstrated that caudatin, one species of C-21 steroidal from Cynanchum auriculatum (C. auriculatum), effectively inhibits human glioma growth in vitro and in vivo through triggering cell cycle arrest and apoptosis. However, little information regarding the antiangiogenic properties of caudatin in human glioma is available. Based on the author's previous study, the antiangiogenic effect of caudatin against human glioma was explored, and the underlying mechanism was investigated. The results suggested that caudatin treatment significantly inhibited HUVEC human umbilical vein endothelial cell proliferation, blocked the HUVECs migration, invasion and capillary-like tube formation by disturbing the vascular endothelial growth factor (VEGF)-VEGFR2-protein kinase B (AKT)/focal adhesion kinase (FAK) signal axis. Notably, caudatin treatment abolished the glioma cell growth by suppression of the in vivo angiogenesis, which involved FAK and AKT dephosphorylation and inhibition of VEGF expression. The findings validated the antiangiogenic potential of caudatin in hunting human glioma. [ABSTRACT FROM AUTHOR]

Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene), which are unique compounds from marine brown algae. In our present study, a procedure for extraction and enrichment of phlorotannins from S. fusiforme with highly antioxidant potentials was established. After comparison of different extraction methods, the optimal extraction conditions were established as follows. The freeze-dried seaweed powder was extracted with 30% ethanol-water solvent with a solid/liquid ratio of 1:5 at temperature of 25 °C for 30 min. After extraction, the phlorotannins were fractioned by different solvents, among which the ethyl acetate fraction exhibited both the highest total phlorotannin content (88.48 ± 0.30 mg PGE/100 mg extract) and the highest antioxidant activities. The extracts obtained from these locations were further purified and characterized using a modified UHPLC-QQQ-MS method. Compounds with 42 different molecular weights were detected and tentatively identified, among which the fuhalol-type phlorotannins were the dominant compounds, followed by phlorethols and fucophlorethols with diverse degree of polymerization. Eckol-type phlorotannins including some newly discovered carmalol derivatives were detected in Sargassum species for the first time. Our study not only described the complex phlorotannins composition in S. fusiforme, but also highlighted the challenges involved in structural elucidation of these compounds. [ABSTRACT FROM AUTHOR]

Lithium abundance derived in metal-poor main-sequence (MS) stars is about three times lower than the value of primordial Li predicted by the standard big bang nucleosynthesis when the baryon density is taken from the cosmic microwave background or the deuterium measurements. This disagreement is generally referred as the lithium problem. We here reconsider the stellar Li evolution from the pre-main sequence (PMS) to the end of the MS phase by introducing the effects of convective overshooting (OV) and residual mass accretion. We show that 7Li could be significantly depleted by convective OV in the PMS phase and then partially restored in the stellar atmosphere by a tail of matter accretion which follows the Li-depletion phase and that could be regulated by EUV photoevaporation. By considering the conventional nuclear burning and microscopic diffusion along the MS, we can reproduce the Spite plateau for stars with initial mass m0 = 0.62-0.80 M⊙, and the Li declining branch for lower mass dwarfs, e.g. m0 = 0.57-0.60 M⊙, for a wide range of metallicities (Z = 0.00001 to Z = 0.0005), starting from an initial Li abundance A(Li) = 2.72. This environmental Li evolution model also offers the possibility to interpret the decrease of Li abundance in extremely metal-poor stars, the Li disparities in spectroscopic binaries and the low Li abundance in planet hosting stars. [ABSTRACT FROM AUTHOR]

The compatibility of poly (vinylidene fluoride) (PVDF) and polyurethane (PU) was studied based on the theoretical analysis of solubility parameter and mixing enthalpy. The results showed that PVDF and PU are partially compatible. Then, the blend membranes of PVDF- PU with 5, 10, and 80 wt.% PVDF content were prepared with the application of solution blending in solvent N, N-dimethylacetamide (DMA). The membranes were characterized by Fourier transformed infrared spectroscopy (FT-IR) to assess the intermolecular interactions. And the morphology of the membranes was studied by scanning electron microscope (SEM). 80wt.% PVDF-PU membrane was porous. However, 5% and 10% PVDF-PU membrane were suitable for pervaporation. The study showed that the degree of swelling (DS) of PVDF-PU membrane increased with the phenol concentration, which suggested that these membranes have stronger sorption capacity to phenol. Then, the pervapration performance of the membranes was examined. The results showed that the pevaporation performances of the blend membranes have been improved comparing with the plain PU membrane. [ABSTRACT FROM AUTHOR]