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Toxoplasma gondii is an opportunistic and pathogenic obligate intracellular parasitic protozoan that is widespread worldwide and can infect most warm-blooded animals, seriously endangering human health and affecting livestock production. Toxoplasmosis caused by T. gondii infection has different clinical manifestations, which are mainly determined by the virulence of T. gondii and host differences. Among the manifestations of this condition, abortion, stillbirth, and fetal malformation can occur if a woman is infected with T. gondii in early pregnancy. Here, we discuss how the T. gondii rhoptry protein affects host pregnancy outcomes and speculate on the related signaling pathways involved. The effects of rhoptry proteins of T. gondii on the placental barrier are complex. Rhoptry proteins not only regulate interferon-regulated genes (IRGs) to ensure the survival of parasites in activated cells but also promote the spread of worms in tissues and the invasive ability of the parasites. The functions of these rhoptry proteins and the associated signaling pathways highlight relevant mechanisms by which Toxoplasma crosses the placental barrier and influences fetal development and will guide future studies to uncover the complexity of the host-pathogen interactions. • Toxoplasma gondii represents a serious threat to human and animal health worldwide. • The ROPs of Toxoplasma gondii play a regulatory role in the invasion of host cells and the proliferation. • Studying the ROPs of Toxoplasma gondii can help us better understand ROPs in other parasites. [ABSTRACT FROM AUTHOR]

The vegetation coverage of temperate grasslands in China has changed substantially due to climate change during the past decades, which significantly affects the function of grassland ecosystems. To appropriately carry out adaptive management and protect temperate grassland vegetation, it is important to understand the variations in fractional vegetation coverage (FVC) of China's temperate grasslands and how they are responding to climate change. Using the GIMMS NDVI and climatic datasets, this study explored the dynamics of FVC and their climatic drivers across the temperate grassland region of China during 1982∼2015. The results showed that the growing season mean FVC increased by 0.12% per year during 1982∼2015. The increases in precipitation and minimum temperature in the growing-season (especially in spring) could enhance the FVC of various vegetation types. In summer, the FVC of temperate steppe and desert steppe could drastically increase with increasing precipitation. In addition, this study found that the impacts of daytime and night-time warming on the FVC of temperate grasslands were asymmetric. Daytime warming can moderately increase FVC of temperate grasslands, while night-time warming could significantly increase it. Furthermore, the increase in summer daytime and night-time temperatures leads to a weak decrease and a moderate increase in FVC, respectively. This asymmetric effect was more evident for the temperate steppe and desert steppe in the central area. In autumn, the temperatures increase had significant positive impacts on the FVC of temperate meadows and steppes. This study highlights the differences in the impacts of climate change at different time scales on the FVC of grasslands with various vegetation types, and indicates that the asymmetric influences of daytime and night-time temperatures in different seasons on FVC must be included in calculating the vegetation coverage of China's temperate grasslands. The results could provide information for maintaining grassland ecosystem functions and managing environmental systems. • The FVC of temperate grasslands has increased by 0.12% per year from 1982 to 2015. • Increases in growing season precipitation and minimum temperature enhanced the FVC. • Nighttime and daytime temperatures have asymmetric effects on the FVC. [ABSTRACT FROM AUTHOR]

• Amorphous carbon coated SnO 2 nanohseets on hard carbon hollow spheres (AC/SnO 2 @HCHS) is successfully constructed. • For the first time, AC/SnO 2 @HCHS were evaluated as potassium-ion battery anodes. • AC/SnO 2 @HCHS anode shows enhanced electrochemical performance with large surface capacitive contributions. Potassium-ion batteries (KIBs) have becoming a prospective energy storage technique, due to the abundant potassium resources in the earth crust, approximate redox potential and similar electrochemical behavior of potassium and lithium. However, the insufficient capacity, poor stability and volume expansion of electrode materials during charge and discharge are main factors restricting the further development of KIBs. This work reports an amorphous carbon coated SnO 2 nanohseets on hard carbon hollow spheres (AC/SnO 2 @HCHS) anode with enhanced potassium storage performance. The HCHS acts as a carrier for SnO 2 nanosheets, providing high electrical conductivity and stable skeleton. The self-assembled SnO 2 nanosheets with high surface area ensures sufficient contact with the electrolyte. Amorphous carbon wrapping can not only relieve SnO 2 volume expansion but also provide surface-induced capacitive capacity. As a consequence, the AC/SnO 2 @HCHS anode presents excellent potassium-ion storage performance with high discharge capacity of 346 mAh g−1 at 0.1 A g−1 over 200 cycles, ultra-long cycling lifetime and outstanding rate capability (236 mAh g−1 at 1 A g−1 over 1000 cycles). [ABSTRACT FROM AUTHOR]

Flexible N doped carbon/bubble-like MoS 2 core/sheath framework (MoS 2 /NCS) is prepared as an anode material for potassium ion batteries. The voids between bubble-like MoS 2 sheath and NCS core can effectively buffer volume expansion. The chemical bonds (C Mo) firmly bridge MoS 2 and NCS together, which further ensures MoS 2 /NCS stable cycling performance. • Flexible N doped carbon/bubble-like MoS 2 core/sheath (MoS 2 /NCS) were constructed. • The as-prepared MoS 2 /NCS has been applied as binder free anode for K-ion batteries. • The voids between bubble-like MoS 2 and NCS can effectively buffer volume expansion. • The chemical bonds firmly bridge MoS 2 and NCS together for stable cycling. Suitable anode materials for potassium ion batteries (KIBs) with high capacity, good reversibility and stable cycling performances are still in large demand. Here, flexible N doped carbon/bubble-like MoS 2 core/sheath framework (MoS 2 /NCS) is prepared as an anode material for potassium ion batteries. The N doped carbon sponge (NCS) skeleton with good conductivity and high surface area guarantees superior rate capability and high stability of MoS 2 /NCS anode. The chemical bonds (C Mo) firmly bridge MoS 2 and NCS together, which further ensures MoS 2 /NCS stable cycling performance. More importantly, volume expansion is greatly buffered during cycling by this unique structure: the voids between bubble-like MoS 2 sheath and NCS core can effectively buffer volume expansion generated during potassium intercalation/deintercalation; the enlarged interlayer spacing contribute more space to buffer volume change; the ultrathin nanosheets can shorten the charge diffusion distance and buffer volume change. As a consequence, MoS 2 /NCS delivers a capacity of 374 mAh g−1 over 200 cycles at 50 mA g−1. Even at 1000 mA g−1, a capacity of 212 mAh g−1 can still be obtained over 1000 cycles. We believe this MoS 2 /NCS structure will highlight the potential of MoS 2 in practical KIBs applications. [ABSTRACT FROM AUTHOR]

In this study, crayfish shell was pyrolyzed at 600 °C to obtain a calcium-rich biochar (CS600). The biochar was saturated with Pb2+ in batch adsorption experiment. Six desorption reagents including HCl, HNO 3 , H 2 SO 4 , NaOH, EDTA and EDTA-2NaCa were then used to desorb Pb2+ from the post-adsorption CS600 to determine the desorption mechanism. Lead adsorption experiments were performed to determine the adsorption capacity of the regenerated CS600. HCl, HNO 3 , EDTA and EDTA-2NaCa presented good desorption effect with desorption rates all over 80%. Most of the regenerated biochars lost their lead adsorption ability due to the destruction of CaCO 3 mineral on their surface. Only the one desorbed by EDTA-2NaCa retained a preferable lead adsorption capacity. EDTA-2NaCa thus is a promising desorption reagent of CS600 for the removal of lead from aqueous solutions. [ABSTRACT FROM AUTHOR]

The feasibility of anammox-based processes for nitrogen-contained wastewater treatment has been verified with different anammox bacteria, however, the ecological niche of anammox bacteria under mainstream conditions is still elusive. In this study, six sludge samples collected from different habitats were utilized to culture anammox bacteria under mainstream conditions, and two distinct anammox genera (Ca. Kuenenia and Ca. Brocadia) with a relative abundance of 6.31% (C1) and 3.09% (C3), respectively, were identified. Notably, the microbial dynamics revealed that anammox bacteria (AMX), ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), Chloroflexi bacteria (CFX), and heterotrophic denitrification bacteria (HDB) were the core members in anammox consortia. However, Ca. Kuenenia and Ca. Brocadia occupied different ecological niches in anammox consortia. The dissolved oxygen and microbial structures of the anammox-continuous stirred tank reactor systems were the main factors to affect their niche differentiation. Meanwhile, comammox might exist in the systems and occupy the ecological niche of AOB in nitrogen cycling. The network analysis suggested that Ignavibacterium could be the associated bacteria in Ca. Kuenenia-dominated consortia, while Ca. Nitrotoga was that in the Ca. Brocadia-dominated consortia. Our findings reveal a valuable reference for the observation of distinct anammox genera under mainstream conditions, which provides theoretical guidance for the engineering application of mainstream anammox-based processes. [Display omitted] • Two anammox genera were detected from activity sludge with distinct habits. • Microbial communities dominated by Ca. Kuenenia and Ca. Brocadia were different. • DO induce the ecological niches of Ca. Kuenenia and Ca. Brocadia. • Microbial interaction contributed to the accumulation of different anammox genera. • Comammox Nitrospira might act on nitrosation under mainstream conditions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Three isomers of the difluoromethane and 1,1-difluoroethane dimer are observed and assigned. • The structure of the three isomers were determined. • The nature of non-covalent interaction within the complex was revealed by QTAIM and SAPT analysis. Abstract The rotational spectra of three isomers of the difluoromethane–1,1-difluoroethane dimer were measured and assigned by using Fourier transform microwave spectroscopy. Experimental results, ab initio calculations and quantum theory of atoms in molecules (QTAIM) analysis confirm that the two subunits in the observed isomers are held together by three weak C H⋯F C interactions. Rotational spectra of all the 13C isotopologues were also observed for all the three isomers. The experimental data leads to precise determination of the substitution (r s) and effective (r 0) structures of the observed isomers. The Symmetry-adapted perturbation theory (SAPT) analysis demonstrates that electrostatic and dispersion terms play a major role in determining the stabilities of the complex. The relative populations of the three observed isomers in the supersonic expansion in helium were estimated as N I / N II / N III ≈ 5/2/6 from relative intensity measurements. [ABSTRACT FROM AUTHOR]

Ti 3+ self-doped TiO 2 /g-C 3 N 4 mesostructured nanosheets heterojunctions (Ti 3+ -TiO 2 /Meso-g-C 3 N 4 ) have been prepared via calcination-sonication assisted method using amino cyanamide as precursors, combined with a solid-state chemical reduction method. The Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions with narrow band gap of ∼2.21 eV possess relative high surface area of ∼73.8 m 2  g −1 , and large pore size of ∼10 nm. Remarkably, the Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions exhibit excellent visible-light-driven photocatalytic activity for degradating phenol in wastewaters. The photocatalytic hydrogen production rate of Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions rise to ∼290.2 μmol h −1  g −1 , which is about 4 and 14 times higher than that of the bare Meso-g-C 3 N 4 and TiO 2 , respectively. The enhanced photocatalytic activity may be ascribed to the synergetic effect of the mesoporous structure providing sufficient surface active sites, and Ti 3+ self-doping and the formed heterojunctions promoting the spatial separation of photogenerated electron-hole pairs. [ABSTRACT FROM AUTHOR]

[Display omitted] Potassium ions batteries (PIBs) have been regarded as a promising choice for electrical energy storage technology due to the wide distribution of potassium resources. However, developing low-cost and robust earth-rich anode materials is still a major challenge for the practical and scalable usage of PIBs. Herein, for the first time, we developed nitrogen doped carbon coating CoS 2 /CuCo 2 S 4 heterostructure (CoS 2 /CuCo 2 S 4 @NCs) hollow spheres and evaluated as anode for PIBs. The CoS 2 and CuCo 2 S 4 heterostructure interface could generate a built-in electric field, which can fasten electrons transportation. The nanostructures could shorten the diffusion length of K+ and provide large surface area to contact with electrolytes. Furthermore, the inner hollow sphere morphology along with the carbon layer could accommodate the volume expansion during cycling. What's more, the N -doped carbon could increase the conductivity of the anodes. Benefitting from the above features, the CoS 2 /CuCo 2 S 4 @NCs displays an outstanding rate capability (309 mAh g−1 at 500 mA g−1 after 250 cycles) and a long-term cycling life (112 mAh g−1 at 1000 mA g−1 after 1000 cycles) in ether-based electrolyte. Conversion reaction mechanism in CoS 2 /CuCo 2 S 4 @NCs anode is also revealed through ex situ XRD characterizations. This work provides a practical direction for investigating metal sulfides as anode for PIBs. [ABSTRACT FROM AUTHOR]

In order to comprehensive understanding of the active substances of Allii macrostemonis bulbus (AMB), this study conducted the extraction, purification, structure and antioxidant activity of AMB polysaccharides. The crude polysaccharides were obtained by hot water and ethanol precipitation extraction, and five purified polysaccharide fractions were obtained (AMBP-1, AMBP-2, AMBP-3, AMBP-4 and AMBP-5) with different molecular weights. Structural characterization of five fractions by chromatography, spectroscopy, TGA and Zeta potential analysis. AMBP-1, AMBP-2 and AMBP-3 were primarily composed of mannose, glucose and galacturonic acid. Whereas AMBP-4 and AMBP-5 were primarily composed of mannose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, xylose. Five fractions possessed differences in characteristic morphology, thermal stability and Zeta potential. Further investigated,the results revealed that five fractions comprised of 1 → 4、1 → 6 linked d -glucopyranose as the main chain with different branch by using methylation with GC-MS and 1D-NMR. Any one of AMB polysaccharides displayed the ability to scavenge free radicals, chelate iron with a dose-effect relationship. Among which AMBP-5 displayed the strongest antioxidant contribute to its rich uronic acid, monosaccharide composition and large molecular weight. This study has enriched the research on the chemical composition of AMB and provides a theoretical basis for developed as a functional food. • Five fractions from Allii macrostemonis bulbus polysaccharides by isolation. • Structural characterization of five fractions were analyzed. • The AMBP-5 fractions possessed strongest in vitro antioxidant activity. [ABSTRACT FROM AUTHOR]