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Background: Hyperpolarized (HP) gas MRI enables the clear visualization of lung structure and function. Clinically relevant biomarkers, such as ventilated defect percentage (VDP) derived from this modality can quantify lung ventilation function. However, long imaging time leads to image quality degradation and causes discomfort to the patients. Although accelerating MRI by undersampling k‐space data is available, accurate reconstruction and segmentation of lung images are quite challenging at high acceleration factors. Purpose: To simultaneously improve the performance of reconstruction and segmentation of pulmonary gas MRI at high acceleration factors by effectively utilizing the complementary information in different tasks. Methods: A complementation‐reinforced network is proposed, which takes the undersampled images as input and outputs both the reconstructed images and the segmentation results of lung ventilation defects. The proposed network comprises a reconstruction branch and a segmentation branch. To effectively exploit the complementary information, several strategies are designed in the proposed network. Firstly, both branches adopt the encoder‐decoder architecture, and their encoders are designed to share convolutional weights for facilitating knowledge transfer. Secondly, a designed feature‐selecting block discriminately feeds shared features into decoders of both branches, which can adaptively pick suitable features for each task. Thirdly, the segmentation branch incorporates the lung mask obtained from the reconstructed images to enhance the accuracy of the segmentation results. Lastly, the proposed network is optimized by a tailored loss function that efficiently combines and balances these two tasks, in order to achieve mutual benefits. Results: Experimental results on the pulmonary HP 129Xe MRI dataset (including 43 healthy subjects and 42 patients) show that the proposed network outperforms state‐of‐the‐art methods at high acceleration factors (4, 5, and 6). The peak signal‐to‐noise ratio (PSNR), structural similarity (SSIM), and Dice score of the proposed network are enhanced to 30.89, 0.875, and 0.892, respectively. Additionally, the VDP obtained from the proposed network has good correlations with that obtained from fully sampled images (r = 0.984). At the highest acceleration factor of 6, the proposed network promotes PSNR, SSIM, and Dice score by 7.79%, 5.39%, and 9.52%, respectively, in comparison to the single‐task models. Conclusion: The proposed method effectively enhances the reconstruction and segmentation performance at high acceleration factors up to 6. It facilitates fast and high‐quality lung imaging and segmentation, and provides valuable support in the clinical diagnosis of lung diseases. [ABSTRACT FROM AUTHOR]

This article explores a 1960 book project on the Japanese Imperial Palace and Garden complex Katsura, entitled Katsura: Tradition and Creation in Japanese Architecture (1960), in collaboration with Walter Gropius, Kenzo Tange, Yasuhiro Ishimoto, and Herbert Bayer, as an experience of modernism and modernity. Through photography and written records, this article traces the rediscovery of the villa by modern architects since the 1930s, from Bruno Taut to Walter Gropius to appreciate the beauty of Katsura and, finally, Yasuhiro Ishimoto's photographic rendering in 1983, to understand the visual interpretation of authenticity and objectivity through developing perspectives of observation. The 1960 book project was a modernist reinvention on the traditional architectural and garden landscape of Katsura. Through Ishimoto's lens, a series of observations and impressions were projected in the modernist eyes that were distinct from traditional experiences of the villa. The meticulous capture of spatial dynamics and layered material presented in this visual tour have provided a new perspective of interpreting the Katsura Palace, which is fundamentally different from traditional ways of documentation and continues in Ishimoto's visual reinterpretation in 1983, mirroring a developing conversation of cultural exchange between Japanese tradition and the West. [ABSTRACT FROM AUTHOR]

Human sperm compete for fertilization. Here, we find that human sperm, unexpectedly, cooperate under conditions mimicking the viscosity contrasts in the female reproductive tract. Sperm attach at the head region to migrate as a cooperative group upon transit into and through a high viscosity medium (15-100 cP) from low viscosity seminal fluid. Sperm groups benefit from higher swimming velocity, exceeding that of individual sperm by over 50%. We find that sperm associated with a group possess high DNA integrity (7% fragmentation index) – a stark contrast to individual sperm exhibiting low DNA integrity (> 50% fragmentation index) – and feature membrane decapacitation factors that mediate sperm attachment to form the group. Cooperative behaviour becomes less prevalent upon capacitation and groups tend to disband as the surrounding viscosity reduces. When sperm from different male sources are present, related sperm preferentially form groups and achieve greater swimming velocity, while unrelated sperm are slowed by their involvement in a group. These findings reveal cooperation as a selective mode of human sperm motion – sperm with high DNA integrity cooperate to transit the highly viscous regions in the female tract and outcompete rival sperm for fertilization – and provide insight into cooperation-based sperm selection strategies for assisted reproduction. Human sperm are shown to cooperate upon transit into high viscosity media with related sperm displaying higher tendencies to cooperate, suggesting sperm attachment is preferential and confers a benefit under inter-ejaculate conditions [ABSTRACT FROM AUTHOR]

Purpose: A better understanding of the nitrogen (N) saturation threshold for plant carbon (C) sequestration would help project the variations of ecosystem C sequestration under the background of increasing N inputs, but the underlying mechanisms are far from clear. This study aimed to elucidate the role of N-induced litter accumulation in mediating the impacts of N addition on plant C sequestration. Methods: Based on a seven-year N addition field experiment in a temperate steppe, we measured soil properties, plant species richness, litter biomass, and aboveground biomass C stocks under mown (low litter accumulation) and unmown conditions (high litter accumulation). Results: The impacts of N addition on plant C sequestration in grasslands were dependent on addition rates and mowing conditions. There was a threshold for the positive impacts of increasing N addition rates on plant community aboveground C stocks under unmown conditions but not under mown conditions. Litter accumulation was a key factor driving the divergent effects of N addition under different conditions. Results of structural equation modelling showed that N addition had direct and positive effects on plant C sequestration both in unmown plots with litter mass < 200 g m−2 and mown plots, and that such positive effects disappeared in unmown plots with litter mass > 200 g m−2. Conclusion: Our findings highlight the indirect role of litter in mediating the impacts of N inputs on ecosystem C cycling through changing the capacity of plant C sequestration. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of dyes is an extremely difficult but very important issue in the field of environmental protection. Two coordination polymers (CPs) [Cu(3-bpah)(HD)]n (1) and [Cu(3-dpye)0.5(HD)]n (2) [3-bpah = N,N'-bis(3-pyridinecarboxamide)-1,2-cyclohexane, 3-dpye = N,N'-bis(3-pyridinecarboxamide)-1,2-ethane, H2HD = hexanedioic acid] were successfully synthesized by tuning the auxiliary ligands under hydrothermal conditions. CPs 1 and 2 exhibited different compositions because of the different N-donor ligands, and were used as precursors for the preparation of metal oxide heterojunctions. Doping foreign elements into intrinsic CP-based materials is an effective way to enhance their photocatalytic activity, and thus we designed a facile method to synthesize a series of carbon-coated metal oxide heterojunctions which were derived from the two Cu-based CPs (Cu@V-1, Cu@V-2, Cu@Mo-1, Cu@Mo-2, Cu@W-1 and Cu@W-2) in this work for the first time. Benefiting from the formation of a carbon shell and regulation of the electronic structure through doping molybdenum and generating the Mo2C phase, the photocatalytic degradation rates were 94.84% for MB, 76.02% for RhB, 52.29% for MO, and 86.18% for CR after 4 h. [ABSTRACT FROM AUTHOR]

The frequency, duration and magnitude of drought are projected to increase in the next few decades, with consequences for community composition and nutrient utilization of plants. Nutrient resorption, a process facilitating plant nutrient conservation, is a crucial driver for ecosystem nutrient cycling. It remains unknown how would extreme drought affect nutrient resorption of plant communities through changing community composition.We examined the contributions of different processes (richness and identity effect of species losses and species gains, as well as the context dependent effect) related with community compositional changes to the alterations of community‐level nutrient resorption efficiency after 4‐year treatments of chronic drought (66% rainfall reduction from May to August) and intense drought (100% rainfall reduction in June and July) in a temperate steppe in Hulun Buir, Inner Mongolia, China.Both chronic and intense drought significantly reduced nutrient resorption efficiency in most of the common species, but did not affect that at the community level. Drought‐induced losses of species made positive contribution to the community‐level nutrient resorption, as they generally had lower nutrient resorption efficiency. Such positive contribution balanced the negative effect of drought on the nutrient resorption of the common species.Our results indicate that drought‐induced changes in community composition, especially those species being lost, were important in mediating the community‐level responses of nutrient resorption to extreme drought in grasslands. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The designing of luminescent metal–organic frameworks (LMOFs) as sensors for the detection of molecules and ions constitutes an active area of research. Four different three-dimensional (3D) unusual LMOFs, namely, {[Zn(3-pda)(TA)]·H2O}n (1), {[Zn(4-pda)(TA)]·2H2O}n (2), [Cd(3-pda)(TA)]n (3), and {[Cd2(4-pda)2(TA)2]·(4-fpia)·H2O}n (4) (3-pda = 1,4-bis(3-pyridylcarboxylamide)benzene, 4-pda = 1,4-bis(4-pyridylcarboxylamide)benzene, 4-fpia = N-(4-formylamino-phenyl)-isonicotinamide, and TA = terephthalic acid) were successfully synthesized by a hydrothermal method and characterized by single-crystal X-ray diffraction. Under solvothermal conditions, a structurally transformational 3D 3-fold interpenetrated porous MOF, [Cd2(4-pda)2(TA)2(DMF)]n (4a), was obtained, which could be further transformed to isostructural [Cu2(4-pda)2(TA)2(DMF)]n (4b) by single-crystal to single-crystal (SCSC) transformation. The effect of N-donor ligands, metal ions and solvents on the structure of MOFs is discussed in detail. A series of luminescence recognition tests proved that complexes 1–4 can be used as luminescent sensors for detecting certain metal cations, oxyanions, and toxic organic solvents in an aqueous environment. Furthermore, the luminescence quenching mechanism and structure–function relationship were studied systematically. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 3 O 4 has a long-term effect to activate persulfate for contaminant degradation. • The activation follows a rate-limited surface radical production mechanism. • Efficiency in persulfate use and stability of Fe 3 O 4 was seen for contaminant removal. • Fe 3 O 4 -based persulfate activation method shows potential for ISCO applications. Highly reactive metal-based materials for persulfate activation have been intensively studied for treatment of groundwater contaminants. However, the long-term efficacy of the readily available metal-oxide additives, which can be more important for groundwater remediation practice, has received minimal attention. In this study, the results of preliminary experiments demonstrated that Fe 3 O 4 was superior to seven metal oxides (MnO, Fe 2 O 3 , MnO 2 , CuO, Cu 2 O, CoO, NiO) and zero-valent iron for activating persulfate to degrade 1,2-dichloropropane. Experiments were then conducted to examine the long-term effects of Fe 3 O 4 -activated persulfate degradation of four contaminants, i.e., 1,2-dichloropropane, 1,1,2-trichloroethane, 1,4-dioxane, and methyl tert -butyl ether (MTBE). The system achieved complete removal of the contaminants in approximately 72 h, which was contrasted to a removal efficiency less than 35 % in the absence of Fe 3 O 4. Highly efficient use of persulfate for contaminant degradation was observed with insignificant production of soluble Fe before depletion of the contaminants. Production of sulfate radical (SO 4 •−) and hydroxyl radical (HO•) via surface reactions was likely the process responsible for the degradation. Ten and five cycles of 1,2-dichloropropane degradation experiments were conducted in deionized water and actual groundwater. These results suggested that the Fe 3 O 4 could retain 80 % of its original activation capacity after 5 cycles, but partial oxidation of Fe 3 O 4 eventually occurred. Production of some Cl-containing degradation-resistant intermediates from degradation of 1,2-DCP was observed and could be mitigated under specific conditions. The results show that Fe 3 O 4 has a long-term effect in activating persulfate for contaminant degradation, which is promising for applications such as permeable reactive barriers and nanoparticle injection for groundwater remediation. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have recently emerged as a type of uniformly and periodically atom-distributed precursor and efficient self-sacrificial template to fabricate hierarchical porous-carbon-related nanostructured functional materials. In this work, we used Cu(II) ions and aromatic dicarboxylic acid to construct [Cu3(4,4′-oba)2(μ2-OH)2(H2O)2]n (4,4′-H2oba = 4,4′-oxybisbenzoic acid) as a precursor for the preparation of carbon nanostructures. Doping foreign elements into intrinsic MOF-based nanomaterials is an effective way to enhance the adsorption property and photocatalytic activity; thus, we designed a facile method to synthesize a vanadium-doped mixture of Cu2O and Cu nanoparticles encapsulated in a Cu-MOF-derived carbon nanostructure (C-V-1) in this work for the first time. Benefiting from the protection of the carbon shell and regulation of the electronic structure by doping vanadium and phase-mixing Cu2O and Cu, the adsorption capacities of C-V-1 for MB, RhB, MO, CR and GV at room temperature are 174.13, 147.06, 179.92, 275.90 and 611.81 mg g−1 in 240 min, respectively, while the photocatalytic degradation rates are 88.14% for MB, 79.80% for RhB, 71.31% for MO, and 71.19% for CR after 4 h. In addition, the degradation rate is larger than 99.01% for GV after only 30 min of UV irradiation. This strategy of using a diverse MOF as a structural and compositional material to create a multifunctional composite/hybrid may expand the opportunities to explore highly efficient, fast and robust adsorbents and photocatalysts for water treatment. [ABSTRACT FROM AUTHOR]

To research the effect of structural diversity on citrate-based coordination polymers (CPs), citric acid (H4cit) was selected to combine with Cu(II) under hydrothermal conditions. A new CP [Cu2(cit)(H2O)2] (1) was synthesized and structurally characterized. The title complex shows a 3D 2,4,6-connected topology with the point symbol of {43·63}{44·66·85}{4}. Inspired by the decomposition and functional molybdenum component, 1 was used as a catalyst precursor to synthesize a carbon-based material (C-1) and a C@Mo material (C-Mo-1) by the chemical vapor deposition (CVD) method and characterized in detail. The selective removal of a contaminant (Congo red) by complex 1, C-1 and C-Mo-1 in the aqueous phase was also comparatively investigated. [ABSTRACT FROM AUTHOR]

The selection of high quality sperm is critical for intracytoplasmic sperm injection (ICSI), a prevalent assisted reproduction technology. However, standard selection methods are time-consuming and fail to recover the most viable sperm, thereby limiting the ICSI success rate. Microfluidics enables rapid selection of viable sperm in a manner representing in vivo processes, however, existing platforms lack clinical applicability. Here, we present FertDish, which integrates the clinically established ICSI Petri dish with a film featuring an array of sperm-selecting microchannels for selection of sperm directly from semen. The FertDish format mimics the clinician-familiar ICSI dish setup, and provides rapid (<10 min) single stage sperm preparation that circumvents standard labour-intensive multi-stage sperm processing steps. Tests with human donor and patient semen samples show that FertDish enables the selection of a high quality sperm sub-population, featuring improvements in DNA fragmentation index of more than 91% (donor) and 74% (patient) versus raw semen and 50% (donor) and 63% (patient) versus standard methods, and a distribution of more than 97% sperm with viable and high level DNA. The FertDish enables a high sperm recovery rate (>3.3 × 105 sperm per mL), and is readily adaptable to the clinical workflow with potential to improve ICSI outcomes. [ABSTRACT FROM AUTHOR]

Background: Aqueous-deficient dry eye disease (ADDED) resulting from dysfunction of the lacrimal gland (LG) is currently incurable. Although LG stem/progenitor cell-based therapy is considered to be a promising strategy for ADDED patients, the lack of a reliable serum-free culture method to obtain enough lacrimal gland stem cells (LGSCs) and the basic standard of LGSC transplantation are obstacles for further research. Methods: Adult mouse LGSCs were cultured in Matrigel-based 3D culture under serum-free culture condition, which contained EGF, FGF10, Wnt3A, and Y-27632. LGSCs were continuously passaged over 40 times every 7 days, and the morphology and cell numbers were recorded. LGSCs were induced to differentiate to ductal cells by reducing Matrigel rigidity, while fetal bovine serum was used for the induction of acinar cells. RT-PCR or qRT-PCR analysis, RNA-sequence analysis, H&E staining, and immunofluorescence were used for characterization and examining the differentiation of LGSCs. LGSCs were allotransplanted into diseased LGs to examine the ability of repairing the damage. The condition of eye orbits was recorded using a camera, the tear production was measured using phenol red-impregnated cotton threads, and the engraftments of LGSCs were examined by immunohistochemistry. Results: We established an efficient 3D serum-free culture for adult mouse LGSCs, in which LGSCs could be continuously passaged for long-term expansion. LGSCs cultured from both the healthy and ADDED mouse LGs expressed stem/progenitor cell markers Krt14, Krt5, P63, and nestin, had the potential to differentiate into acinar or ductal-like cells in vitro and could engraft into diseased LGs and relieve symptoms of ADDED after orthotopic injection of LGSCs. Conclusion: We successfully established an efficient serum-free culture for adult mouse LGSCs aiming at LG repair for the first time. Our approach provides an excellent theoretical and technical reference for future clinical research for ADDED stem cell therapy. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD) is a complex process with high morbitity and can cause liver dysfunction, which contains a wide spectrum of hepatic lesions, including steatohepatitis, fibrosis, cirrhosis, and eventually hepatocellular carcinoma. To date, the molecular mechanisms for ALD have not been fully explored and an effective therapy is still missing. Overwhelming evidence shows dysregulation of noncoding RNAs (ncRNAs), particularly microRNAs (miRNAs), is correlated with etiopathogenesis and progress of ALD including hepatocyte damage, disrupted lipid metabolism, aggressive inflammatory responses, oxidative stress, programmed cell death, fibrosis, and epigenetic changes induced by alcohol. For example, circulating miRNA‐122 is a marker of hepatocyte damage, and miRNA‐155 is a potential marker of inflammation, indicating their diagnosis therapeutic potential in ALD. In addition, roles for long noncoding RNAs (lncRNAs) and circular RNAs in ALD are being uncovered. Further, circulating ncRNAs and exosome‐derived ncRNAs have attracted more attention lately, suggesting a role in the prevention and treatment of ALD. This review covers the roles of ncRNAs in ALD, and the potential uses as markers for diagnosis and therapeutic options. [ABSTRACT FROM AUTHOR]

Plant–soil feedbacks have important effects on plant communities, but most theory has been derived from experiments on intraspecific plant–soil feedbacks. Much less is known about how interspecific plant–soil feedbacks affect coexistence and plant communities, due in part to experimental and analytical challenges. Here, we propose a framework for evaluating plant–soil feedbacks among multiple interacting species that incorporates 1) the average effect each species has on conspecific and heterospecific neighbors via how they modify soil biota, 2) the average response of each species to the soil modifications made by neighboring species, and 3) intraspecific feedback. We refer to this as the 'effect–response–intraspecific' (ERI) model. We used individual‐based models to evaluate the relative importance of intraspecific and interspecific soil feedback in determining species abundance ranks in simulated plant communities. To compare the heuristic value of the ERI model to that of an established model in which effects and responses to soil feedback are not explicitly recognized, we evaluated a 'full‐factorial' model in which soil feedbacks among five plant species were measured and then explicitly modeled. The ERI model indicated that the response to interspecific plant–soil feedbacks was the key factor for species' abundance rank without spatial structure. In contrast, interspecific plant–soil feedback had no impact on species abundance with spatial structure, and intraspecific feedback became dominant. Thus, our models predict that the relative importance of intraspecific and interspecific feedbacks changes as a function of the degree of spatial structure in a system. Overall, the ERI model provides a novel and tractable framework for evaluating complex multi‐species plant–soil feedbacks. [ABSTRACT FROM AUTHOR]

Edible films from chitosan (CH) containing various amount of acorn starch (AS) and eugenol (Eu) were developed by casting and solvent-evaporation method, and their physico-chemical, barrier, antimicrobial, antioxidant and structural properties were also investigated. The experimental data showed that an appropriate proportion of AS could improve the mechanical and barrier properties of the film, and the incorporation of Eu in the film significantly improved the flexibility, barrier, hydrophobicity, antimicrobial and antioxidant properties. The results showed that the optimum comprehensive properties of the film were obtained when the mass ratio of AS to CH was 0.9 and the content of Eu was 9%. Possible intermolecular interactions between CH, AS and Eu were confirmed by Fourier-transform infrared spectroscopy (FTIR). SEM indicated that a good compatibility was present between CH and AS, and Eu was well emulsified and dispersed in the film matrix network. TG and DTG curves further confirmed Eu present in the film matrix network. Such edible films can provide new ways for packaging industries in developing active packaging materials. Unlabelled Image • Eugenol had excellent antioxidant and antimicrobial activity. • A unique compatibility can be achieved between appropriate proportion CH, AS and Eu. • Edible film based on CH, AS andEu had good antimicrobial, antioxidant activity and physico-chemical properties. [ABSTRACT FROM AUTHOR]

The cag pathogenicity island (cag PAI) is the main virulence factor of gastric carcinoma induced by Helicobacter pylori (H. pylori). The lytic transglycosylase Cag4 is an important component that assists in the translocation of the bacterial oncoprotein CagA and maintains the peptidoglycan cycle. The allosteric regulation of Cag4 has been preliminarily demonstrated to inhibit H. pylori infection. Unfortunately, a rapid screening technology for allosteric regulators of Cag4 has not been established. In this study, a novel Cag4-double nanoporous gold (NPG) biosensor based on enzyme-inorganic co-catalysis was constructed using the heterologously expressed H. pylori 26695 Cag4 as the biological recognition element for screening Cag4 allosteric regulators. The results showed that chitosan or carboxymethyl chitosan was a mixed Cag4 inhibitor combining non-competition with uncompetition. The inhibition constants were K i ' Chitosan = 0.88909 mg/mL and K i ' Carboxymethyl chitosan = 1.13480 mg/mL, respectively. Surprisingly, D-(+)-cellobiose showed the activation effect of Cag4 on E. coli MG1655 cell wall lysis by decreasing the K a value by 29.7% and increasing the V max value by 71.3%. In addition, molecular docking revealed the importance of the polarity of the C 2 substituent group with glucose as the main structure in the Cag4 allosteric regulator. This study provides a fast and useful platform for screening potential new drugs based on the Cag4 allosteric regulator. [ABSTRACT FROM AUTHOR]

Excessive emission of inorganic ions and organic molecules can pose a potential threat to human health and the environment. Therefore, finding a way to detect contaminants is crucial. Coordination polymers (CPs) are of great practical importance as effective chemical sensors. Secondary auxiliary ligands with different functional groups were synthesized (by a hydrothermal method) and characterized: {[Cd2(3-dpyp)(1,3-BDC)2]·H2O}n (1), {[Cd(3-dpyp)0.5(1,3-BDC)(H2O)2]·H2O}n (2), {[Cd2(3-dpyp)(5-MIP)2(H2O)3]·2H2O}n (3) and {[Cd(3-dpyp)(5-HIP)]·1.5H2O}n (4), where 3-dpyp = N,N′-di(3-pyridinecarboxamide)-1,3-propane, 1,3-H2BDC = 1,3-benzenedicarboxylic acid, 5-H2MIP = 5-methylisophthalic acid and 5-H2HIP = 5-hydroxyisophthalic acid. Single-crystal X-ray diffraction (SCXRD) analysis showed that the four Cd-CPs exhibited fascinating two/three-dimensional structures. Moreover, Cd-CP-1–4 showed excellent stability in the pH range of 1–14 and in different organic solvents. Powder X-ray diffraction analysis and thermogravimetric analysis indicated that the Cd-CPs possessed high chemical and thermal stabilities. Furthermore, with the aim of "using waste to treat waste", fluorescence properties showed that Cd-CP-1–4 could be used as multi-response sensors for Fe3+, MnO4− and nitrobenzene with high sensitivity, selectivity and efficiency. [ABSTRACT FROM AUTHOR]

Hyperpolarized (HP) gas (e.g., 3He or 129Xe) dynamic MRI could visualize the lung ventilation process, which provides characteristics regarding lung physiology and pathophysiology. Compressed sensing (CS) is generally used to increase the temporal resolution of such dynamic MRI. Nevertheless, the acceleration factor of CS is constant, which results in difficulties in precisely observing and/or measuring dynamic ventilation process due to bifurcating network structure of the lung. Here, an adaptive strategy is proposed to highly undersample pulmonary HP dynamic k-space data, according to the characteristics of both lung structure and gas motion. After that, a valid reconstruction algorithm is developed to reconstruct dynamic MR images, considering the low-rank, global sparsity, gas-inflow effects, and joint sparsity. Both the simulation and the in vivo results verify that the proposed approach outperforms the state-of-the-art methods both in qualitative and quantitative comparisons. In particular, the proposed method acquires 33 frames within 6.67 s (more than double the temporal resolution of the recently proposed strategy), and achieves high-image quality [the improvements are 29.63%, 3.19%, 2.08%, and 13.03% regarding the mean absolute error (MAE), structural similarity index (SSIM), quality index based on local variance (QILV), and contrast-to-noise ratio (CNR) comparisons]. This provides accurate structural and functional information for early detection of obstructive lung diseases. [ABSTRACT FROM AUTHOR]

Abstract In this study, a taste bud tissue biosensor was prepared by a starch-sodium alginate cross-linking fixation method. Capsaicin was used as a TRPV1 noxious ion channel activator to investigate the antagonism kinetics of six different substances on capsaicin. The results showed that capsazepine, AMG517, loureirin B, and tetrahydropalmatine were all competitive allosteric regulatory ligands for capsaicin, while aconitine and anandamide were mixed allosteric regulatory ligand that combines non-competition and competition effect. Through analyzing the kinetic parameters of capsaicin and its competitive allosteric regulatory ligands, and comparing the structures between spicy substances and endocannabinoids, the importance of amide groups and similar groups in the allosteric regulation of cannabinoids (CB) receptors and analgesic mechanism was elucidated. This indicates that vanilloid activators turn on the TRPV1 ion channel to transmit only pain and other nociceptive signals, while capsaicin and its competitive ligands are capable of activating intracellular G protein/PI3K/PIP2 signaling pathways by binding to endogenous cannabinoid receptors, and then increase intracellular PIP2 levels (the increasing PIP2 can competitively replace capsaicin and other vanilloid activators), thereby closing the TRPV1 channel and exerting the analgesic effect. The elucidation of this mechanism of pain and analgesia will lay the theoretical foundation and new ideas for investigating nociceptive signal and screening potential analgesic drugs. Highlights • First research on TRPV1 related analgesic drugs through biosensors. • Mathematical models were used to reveal the antagonistic type and effects on TRPV1. • The role of amide groups and their similar groups in analgesic drugs was discovered. • First revealed the role of allosteric regulation of CB receptors in analgesia. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchically dual‐mesoporous TiO2 microspheres have been synthesized by a solvothermal process in the presence of 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIm][BF4]) and diethylenetriamine (DETA) as co‐templates. Secondary mesostructured defects in the hierarchical TiO2 microspheres produce oxygen vacancies, which not only significantly enhance photocatalytic activity in the degradation of methylene blue (1.7 times that with P25) and acetone (2.9 times that with P25), but are also beneficial for lithium storage. Moreover, we propose a mechanism to rationalize the role of this dual mesoporosity of the TiO2 microspheres in enhancing molecular diffusion, ion transportation, and electronic transitions. [ABSTRACT FROM AUTHOR]

Dynamic hyperpolarized (HP) 129 Xe MRI is able to visualize the process of lung ventilation, which potentially provides unique information about lung physiology and pathophysiology. However, the longitudinal magnetization of HP 129 Xe is nonrenewable, making it difficult to achieve high image quality while maintaining high temporal-spatial resolution in the pulmonary dynamic MRI. In this paper, we propose a new accelerated dynamic HP 129 Xe MRI scheme incorporating the low-rank, sparse and gas-inflow effects (L + S + G) constraints. According to the gas-inflow effects of HP gas during the lung inspiratory process, a variable-flip-angle (VFA) strategy is designed to compensate for the rapid attenuation of the magnetization. After undersampling k-space data, an effective reconstruction algorithm considering the low-rank, sparse and gas-inflow effects constraints is developed to reconstruct dynamic MR images. In this way, the temporal and spatial resolution of dynamic MR images is improved and the artifacts are lessened. Simulation and in vivo experiments implemented on the phantom and healthy volunteers demonstrate that the proposed method is not only feasible and effective to compensate for the decay of the magnetization, but also has a significant improvement compared with the conventional reconstruction algorithms ( P -values are less than 0.05). This confirms the superior performance of the proposed designs and their ability to maintain high quality and temporal-spatial resolution. [ABSTRACT FROM AUTHOR]

Glioma is one of the most malignant forms of brain tumor, and has been of persistent concern due to its high recurrence and mortality rates, and limited therapeutic options. As a cardiac glycoside, ouabain has widespread applications in congestive heart diseases due to its positive cardiac inotropic effect by inhibiting Na+/K+‑ATPase. Previous studies have demonstrated that ouabain has antitumor activity in several types of human tumor, including glioma. However, the exact underlying mechanism remains to be elucidated. The purpose of present study was to elucidate the effect of ouabain on human glioma cell apoptosis and investigate the exact mechanism. U‑87MG cells were treated with various concentrations of ouabain for 24 h, following which cell viability and survival rate were assessed using a 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay. The dynamic changes and cell motility were observed using digital holographic microscopy. Additionally, western blot analysis and high‑content screening assays were used to detect the protein expression levels of phosphorylated (p‑)Akt, mammalian target of rapamycin (mTOR), p‑mTOR and hypoxia‑inducible factor (HIF)‑1α, respectively. Compared with the control group, ouabain suppressed U‑87MG cell survival, and attenuated cell motility in a dose‑dependent manner (P<0.01). The downregulation of p‑Akt, mTOR, p‑mTOR and HIF‑1α were observed following treatment with 2.5 and 25 μmol/l of ouabain. These results suggested that ouabain exerted suppressive effects on tumor cell growth and motility, leading to cell death via regulating the intracellular Akt/mTOR signaling pathway and inhibiting the expression of HIF‑1α in glioma cells. The present study examined the mechanism underlying the antitumor property of ouabain, providing a novel potential therapeutic agent for glioma treatment. [ABSTRACT FROM AUTHOR]

Background Exaggerated inflammation that characterizes necrotizing enterocolitis (NEC) is caused by the invasion of pathogens through an immature intestinal barrier. Vitamin A (VA) and retinoic acid (RA) play important roles in the growth of epithelial tissue and in modulating immune function. Objective To investigate the roles of VA and RA in the development of NEC. Methods Levels of serum retinol in patients and in a NEC mouse model were detected with high-performance liquid chromatography. Bacterial communities of NEC mice treated with VA or PBS were detected by high-throughput sequencing. In vitro and in vivo , levels of inflammatory factors were measured by ELISA and RT-PCR, and expression levels of claudin-1, occludin, and ZO-1 were detected by Western blotting. Transepithelial electrical resistance (TEER) was measured in Caco-2 cell monolayers. Results The level of VA in the NEC patients was lower than in the control patients. In the NEC mice that were treated with VA versus PBS, the proportion of Escherichia-Shigella was lower, while the abundance of Bacteroides was markedly higher. Both in vivo and in vitro , the levels of inflammatory factors were significantly reduced, while the expression levels of claudin-1, occludin, and ZO-1 were increased, after the VA and RA treatments. Meanwhile, TEER was increased and lipopolysaccharide-induced damage was reduced in Caco-2 cell monolayers after RA treatment. Conclusions These results suggest that VA may regulate intestinal flora, alleviate inflammatory reactions, and enhance the intestinal epithelial barrier in NEC. Thus, VA may be an effective drug for providing protection against NEC in newborns. [ABSTRACT FROM AUTHOR]

RATIONALE: Koumine is one of the major components of total alkaloids from Gelsemium. Koumine possesses a variety of interesting pharmacological effects, including anti-tumor, anti-inflammatory, and anxiolytic activities. It might be a promising lead drug because of its pharmacological activities and mild toxicity. However, little information is available on the metabolism of koumine. METHODS: A rapid and accurate high-performance liquid chromatography/quadrupole-time-of-flight (HPLC/QqTOF) mass spectrometry method was applied to characterize koumine metabolites. Multiple scans of koumine metabolites, which were formed in rat liver S9, were automatically performed simultaneously through auto MS/MS mode acquisition in only a 30-min analysis. The structural elucidation of these metabolites was performed by comparing their changes in accurate molecular masses and product ions with those of the parent drug or metabolites. RESULTS: As a result, a total of eleven metabolites of koumine were identified, of which nine new metabolites were found. The present results showed that the N-demethylenation, hydrogenation and the oxidation were the three main metabolic pathways of koumine. CONCLUSIONS: This was the first investigation of in vitro metabolism of koumine in rat liver S9 using a sensitive and specific HPLC/QqTOF-MS method. The possible metabolic pathways of koumine were tentatively proposed based on the structural elucidations of these metabolites. This work may be useful in the in vivo metabolism of koumine in animals and humans. [ABSTRACT FROM AUTHOR]

Gliomas, especially low-grade gliomas, are highly epileptogenic brain tumors. Histopathological information is valuable in evaluating the diagnosis and/or biologic behavior of various gliomas. Here we explored the clinical data and histopathological predictors of the occurrence of epilepsy in patients with gliomas. A retrospective study examined 310 consecutive patients who had undergone surgical treatment for gliomas in our institution from January 2013 to January 2015. Clinical data and pathological examination results were analyzed. Literatures regarding the predictors and etiology of glioma associated epileptic seizures in the period of 1995–2015 were also reviewed. A total of 234 (75.5%) astrocytic tumors and 76 (24.5%) oligodendrial tumors were included. At diagnosis, 33.6% of patients had epileptic seizures. Multivariate analysis revealed cortex involvement (OR = 7.991, 95%CI = 1.599–39.926), lower World Health Organization grade (OR = 3.584, 95%CI = 1.032–12.346) and topoisomerase II (TopoII) positivity (OR = 0.943, 95%CI = 0.903–0.982) were strong predictors for preoperative epileptic seizures. Gender, disease course, tumor classification, location or volume did not significantly affect epileptic seizure occurrence. Forty-three publications involved glioma-associated epilepsy were found in PubMed online database and key data were extracted and summarized. The present studies on glioma-related epilepsy are relatively limited and inconsistent. Low-grade gliomas, cortex involvement and TopoII positivity were independent predictors of a history of epileptic seizures at diagnosis. Further studies to examine the underlying mechanism of topoisomerase II as well as other molecules in epilepsy occurrence in brain gliomas are needed in the future. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) that are derived from coordination polymers (CPs) and which have controllable structures have served as a significant class of sorbents in renewable materials. However, it is difficult to achieve efficient conversion of CPs to small-diameter CNTs (SDCNTs) via chemical vapor deposition (CVD). As described herein, we first report the large-scale growth of SDCNTs from a Co-based CP. The oxygen atoms of trimesic acid (BTC) which surround the Co-based CP crystals impede the aggregation of Co nanocatalysts so that they effectively serve as a unique "sieve" which allows the catalyst to promote the formation of SDCNTs during the CVD process. CNTs with a diameter of ∼14 nm evolved from the pristine CP architecture. This strategy is novel and provides a new approach for the large-scale preparation of SDCNTs, and it that may facilitate the development of high performance and inexpensive sorbents as well as photocatalysts for water treatment. A simple and highly-efficiency strategy has been designed for the general oriented preparation of SDCNTs from simple oxygen vacancy Co-based CPs. This strategy can be widely used to synthesize different morphology-retaining CNT-based nanostructures via the modulation of Co-based CPs. The SDCNTs exhibit outstanding properties as selective sorbents and a photodegradation-induced electrostatic interaction mechanism is proposed for the targeted adsorption of dyes and drugs. [Display omitted] • Yields of Co-BTC and MWCNT-BTC are over 1.5 times than previous works, respectively. • The diameter of MWCNT-BTC is smaller and more uniform than that reported previously. • The free oxygen atoms play a critical role in the nucleation and growth of SDCNTs. • MWCNT-BTC can be served as an excellent selective adsorbent and photocatalyst. [ABSTRACT FROM AUTHOR]

Successful exotic plant invasions are likely to be caused by multiple, non-mutually exclusive mechanisms, and it is exceptionally difficult to weight the relative importance of these mechanisms identified in different experiments. To this end we used individual-based models to explore how integrating empirical results from experiments might help to elucidate the relative importance of seed origin, biogeographic differences in competitive outcomes, and disturbance in exotic plant invasion. We integrated results from (1) competition experiments between Centaurea solstitialis derived from populations in the non-native range (California), the native range (Spain), and co-occurring native species from both ranges, (2) seed production by Centaurea plants from the different ranges grown in a common-garden environment, and (3) responses to disturbance experiments with plants from different native and non-native ranges. Californian C. solstitialis reached slightly higher abundances than its Spanish counterparts in every scenario, mainly due to higher seed production of Californians than their Spanish conspecifics, indicating the potential importance of evolutionary changes in the non-native range. In the absence of disturbance, grass species native to Europe showed stronger competitive effects on C. solstitialis than grass species native to North America, suggesting that release from competition in the native range may have some explanatory power for successful C. solstitialis invasion. However, the intensity of competition depended on the disturbance regime used in models. When intense disturbance was incorporated into the model, C. solstitialis was favored, with plants from Californian seed sources reaching higher densities than plants from Spanish seed sources. Our results are consistent with the idea that disproportional positive responses to disturbance in California, relative to those in the invader's native range of Spain, may be an important factor in the dominance of C. solstitialis in its non-native ranges. It is not clear why disturbance would have more beneficial effects on the invader in its non-native range, but the powerful effects of disturbance appear to interact in subtle ways with biogeographic differences in evolutionary trends, competitive intensities, life histories, and reproductive rates. [ABSTRACT FROM AUTHOR]

Inhibition or disruption of biofilms has been recognized as an important means to eradicate Helicobacter pylori (H. pylori) infection. However, a fast and efficient drug screening method against H. pylori biofilms has not yet been established. Therefore, AlpB, an important outer membrane protein in H. pylori biofilm formation, was selected as a biological recognition element to screen anti-biofilm drugs in this study. A novel AlpB/colloidal gold (CG)/nanoporous gold (NPG)/Nafion-reduced graphene oxide (rGO)/glassy carbon electrode (GCE) biosensor was constructed based on the heterologous expression of AlpB. The prepared AlpB-based biosensor not only successfully identified six anti-biofilm drugs, but also evaluated the sensitivity and action intensity of different anti-biofilm drugs binding to AlpB by interaction kinetics analysis. The sensitivity order of AlpB to the six anti-biofilm drugs was: allicin > erythromycin > SCC > curcumin > rifampicin > NAC and the action intensity of the six anti-biofilm drugs on AlpB was: rifampicin > NAC > allicin > erythromycin > SCC > curcumin. In addition, molecular docking results showed that the six anti-biofilm drugs might exert their anti-biofilm effects by spontaneously binding to the conserved region of AlpB protein. This study provided a rapid screening platform and a unified data processing method for potential anti-biofilm drug development. • An anti- H. pylori biofilm drug screening biosensor was designed and constructed. • Several anti- H. pylori biofilm drugs were screened and evaluated using the biosensor. • The inhibition intensity of anti-biofilm drugs was calculated by kinetics model. • Molecular interactions of anti-biofilm drugs with AlpB protein were analyzed. [ABSTRACT FROM AUTHOR]

RATIONALE: Allocryptopine (AL) and protopine (PR) have been extensively studied because of their anti-parasitic, antiarrhythmic, anti-thrombotic, anti-inflammatory and anti-bacterial activity. However, limited information on the pharmacokinetics and metabolism of AL and PR has been reported. Therefore, the purpose of the present study was to investigate the in vitro metabolism of AL and PR in rat liver S9 using a rapid and accurate high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/QqTOFMS) method. METHODS: The incubation mixture was processed with 15% trichloroacetic acid (TCA). Multiple scans of AL and PR metabolites and accurate mass measurements were automatically performed simultaneously through data-dependent acquisition in only a 30-min analysis. The structural elucidations of these metabolites were performed by comparing their changes in accurate molecular masses and product ions with those of the precursor ion or metabolite. RESULTS: Eight and five metabolites of AL and PR were identified in rat liver S9, respectively. Among these metabolites, seven and two metabolites of AL and PR were identified in the first time, respectively. The demethylenation of the 2,3-methylenedioxy, the demethylation of the 9,10-vicinal methoxyl group and the 2,3-methylenedioxy group were the main metabolic pathways of AL and PR in liver S9, respectively. In addition, the cleavage of the methylenedioxy group of the drugs and subsequent methylation or O-demethylation were also the common metabolic pathways of drugs in liver S9. In addition, the hydroxylation reaction was also the metabolic pathway of AL. CONCLUSIONS: This was the first investigation of in vitro metabolism of AL and PR in rat liver S9. The detailed structural elucidations of AL and PR metabolites were performed using a rapid and accurate HPLC/QqTOFMS method. The metabolic pathways of AL and PR in rat were tentatively proposed based on these characterized metabolites and early reports. [ABSTRACT FROM AUTHOR]

Block copolymer lithography is emerging as one of the leading technologies for patterning nanoscale dense features. In almost all potential applications of this technology, control over the orientation of cylindrical and lamellar domains is required for pattern transfer from the block copolymer film. This review highlights the state-of-art development of brushes to modify the substrates to control the assembly behaviors of block copolymers in films. Selected important contributions to the development of self-assembled monolayers, polymer brushes and mats, and chemically patterned brushes are discussed. [ABSTRACT FROM AUTHOR]

Three new lycopodium alkaloids, huperserramines A-C ( 1- 3, resp.), along with 15 known ones, lycopodine-6 α,11 α-diol ( 4), lycoposerramine H ( 5), lycoposerramine I ( 6), lycopodine-6 α-ol ( 7), lycoposerramine M ( 8), diphaladine A ( 9), lycoposerramine K ( 10), lycoposerramine W ( 11), huperzine M ( 12), luciduline ( 13), phlegmariuine N ( 14), huperzine A ( 15), huperzine B ( 16), lycodine ( 17), and lycoposerramine R ( 18), were isolated from the whole plant of Huperzia serrata. Their structures were established by spectroscopic methods, including 2D-NMR and MS analyses. All the isolates were evaluated for their inhibitory effects on acetylcholinesterase (AChE) and α-glucosidase. As a result, lycopodine-6 α,11 α-diol ( 4) exhibited more potent α-glucosidase inhibitory activity ( IC50 148±5.5 μ M) than the positive control acarbose ( IC50 376.3±2.7 μ M). [ABSTRACT FROM AUTHOR]

Newcastle disease virus (NDV) isolates contain genomes of 15,186, 15,192 or 15,198 nucleotides (nt). The length differences reflect a 6-nt insert in the 5′ (downstream) non-translated region (NTR) of the N gene (15,192-nt genome) or a 12-nt insert in the ORF encoding the P and V proteins (causing a 4-amino acid insert; 15,198-nt genome). We evaluated the role of these inserts in the N and P genes on viral replication and pathogenicity by inserting them into genomes of two NDV strains that have natural genome lengths of 15,186 nt and represent two different pathotypes, namely the mesogenic strain Beaudette C (BC) and the velogenic strain GB Texas (GBT). Our results showed that the 6-nt and 12-nt inserts did not detectably affect N gene expression or P protein function. The inserts had no effect on the replication or virulence of the highly virulent GBT strain but showed modest degree of attenuation in mesogenic strain BC. We also deleted a naturally-occurring 6-nt insertion in the N gene from a highly virulent 15,192-nt genome-length virus, strain Banjarmasin. This resulted in reduced replication in vitro and reduced virulence in vivo. Thus, although these inserts had no evident effect on gene expression, protein function, or replication in vivo, they did affect virulence in two of the three tested strains. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori) is the main non-genetic factor leading to gastric cancer. Due to the important role of urease produced by H. pylori in its initial colonization, survival, and infection, the activity inhibition of urease has been proven to be a promising therapeutic strategy for H. pylori infection. Therefore, the screening of effective urease inhibitors has become an important direction for the development of new therapeutic drugs. In this study, a novel biosensor for rapid screening of H. pylori urease inhibitors was constructed based on glassy carbon electrode (GCE) modified by heterologously expressed H. pylori 26695 urease b subunit (HPUb), Pt nanoparticles, and nanoporous gold (NPG). Five inhibitors were successfully screened for HPUb using the proposed biosensor (HPUb/Pt/NPG/GCE). The inhibition constants calculated according to the established mathematical model indicated that the inhibitory intensity order of these inhibitors was methylurea > acetamide > formamide > acetohydroxamic acid > hydroxyurea. Combining the inhibition constant of urease inhibitors with the molecular binding mechanism of the urease inhibitor and HPUb, it can be inferred that the non-polar long-chain modification of one of the primary amino groups based on the molecular structure of urea is a promising direction for the development of high-efficiency urease inhibitors. The elucidation of this mechanism will provide a theoretical foundation and new ideas for the design of competitive urease inhibitors based on urea structure and the development of new anti H. pylori drugs. • A Helicobacter pylori urease biosensor is created for screening of urease inhibitors. • Several competitive Helicobacter pylori urease inhibitors are discovered. • Mathematical model for calculating the inhibition constant of urease inhibitor. [ABSTRACT FROM AUTHOR]

The data confirm the results reported in the figure and indicate that the 6 and 12h data were obtained on the same blot whereas the 24h data were obtained on a separate blot. For one statement ("In the 2-week old chickens that were immunized with Ban/AF or LaSota, no challenge virus was detected on either day (day 4 or 7) by inoculation into embryonated eggs or by cell culture methods (data not shown)."). [Extracted from the article]

Question What are the interacting effects of stress and disturbance on both competition and facilitation, and ultimately their impact on diversity and species ranges? Location Simulated data. Method We extended the spatially explicit model of Xiao et al. ( Oikos, 118, 2009, 1343) to consider how stress and disturbance - operating alone or together - affect species distributions through varying biotic interactions. Results In the absence of facilitation, species ranges only occurred within the limits of a triangular zone, which can be considered equivalent to Grime's C-S-R triangle. Competitive species were distributed in low stress and disturbance conditions. Stress- and disturbance-tolerant species occurred in more stressed and disturbed environments. Species richness followed a hump-shaped relationship with a hotspot of diversity occurring close to the centre of the C-S-R triangle. In contrast, facilitation was able to dampen the negative impacts of stress and disturbance acting either solely or simultaneously, but this influence was not simply the sum of the effects of the processes operating independently on the two environmental gradients. Facilitation extended species distributions along both the stress and disturbance gradients and displaced the hotspot of diversity into the centre of the response surface. Conclusions Facilitation was able to promote the occurrence and persistence of communities in highly stressed and disturbed conditions, i.e. allowing a stable community to exist beyond the limits of the C-S-R triangle. We also showed that facilitation can be an important mechanism driving the displacement of hotspots of diversity from benign toward intermediate stressed and disturbed environments. [ABSTRACT FROM AUTHOR]

The mechanisms regulating switches in species interactions along gradients of stress are yet to be fully elucidated. In particular, the role of temporal variability in environmental severity or consumer pressure has been not explored either empirically or theoretically. Here, through a spatially explicit model (i.e. a two-dimensional lattice), we show that variations in the temporal variance of environmental stress can be as important as those in the mean intensity in regulating the spatial distribution and coexistence range of species differing in their relative competitive ability and tolerance to stress, as well as the direction and magnitude of their interactions. In addition, our simulations suggest that enhanced temporal fluctuations in environmental stressors can enhance absolute levels of stress perceived by interacting species. This study shows that tests including both the mean and temporal variance of environmental stress will be key to forecast changes in species interactions under different scenarios of climate change. [ABSTRACT FROM AUTHOR]

Mono-dominance by invasive species provides opportunities to explore determinants of plant distributions and abundance; however, linking mechanistic results from small scale experiments to patterns in nature is difficult. We used experimentally derived competitive effects of an invader in North America, Acroptilon repens, on species with which it co-occurs in its native range of Uzbekistan and on species with which it occurs in its non-native ranges in North America, in individual-based models. We found that competitive effects yielded relative abundances of Acroptilon and other species in models that were qualitatively similar to those observed in the field in the two ranges. In its non-native range, Acroptilon can occur in nearly pure monocultures at local scales, whereas such nearly pure stands of Acroptilon appear to be much less common in its native range. Experimentally derived competitive effects of Acroptilon on other species predicted Acroptilon to be 4–9 times more proportionally abundant than natives in the North American models, but proportionally equal to or less than the abundance of natives in the Eurasian models. Our results suggest a novel way to integrate complex combinations of interactions simultaneously, and that biogeographical differences in the competitive effects of an invader correspond well with biogeographical differences in abundance and impact. [ABSTRACT FROM AUTHOR]

Highlights: [•] We quantified indirect effects in a system of three competitors with a spatially explicit model. [•] We observed two negative and one positive indirect interaction in a system of three competitors. [•] The balance of the three indirect interactions becomes negative in certain conditions. [•] This balance induces generally a competition enhancement and no net indirect facilitation. [•] Rarity of net indirect facilitation in plant communities is likely due to negative indirect interactions. [Copyright &y& Elsevier]

Dominant plants play crucial roles in supporting the functioning of terrestrial ecosystems. Plants can influence the spatial heterogeneity of environmental factors, as well as the spatial turnover in the composition of soil communities (i.e. β‐diversity of soil communities). However, we still poorly understand how dominant plants drive the spatial turnover in multiple ecosystem functions (β‐multifunctionality hereafter), and to which extent the effects of dominant plants are mediated by changes in environmental heterogeneity and the β‐diversity of soil communities.Antarctica supports one of the most challenging environments on the planet including low temperature and water availability. Here, we collected soil samples under three dominant plants (lichen, moss and vascular plants) and bare ground. We measured carbon storage, nutrient availability, nutrient decomposition, microbial biomass and pathogen control to calculate β‐multifunctionality.Both non‐vascular and vascular plants were associated with increased β‐multifunctionality compared to bare ground. We further showed that lichen mainly affected β‐multifunctionality through soil temperature heterogeneity and β‐bacterial diversity. Similarly, moss mainly affected β‐multifunctionality through the spatial heterogeneity of soil water content and β‐bacterial diversity. However, vascular plants did not significantly affect environmental heterogeneity. Instead, the responses of β‐multifunctionality to vascular plants were mainly driven by the β‐diversity of soil communities. These results indicate that environmental heterogeneity is important for turnover in multiple ecosystem functions in early successional stages (dominated by non‐vascular plants), while the importance of soil communities' heterogeneity becomes more significant in late successional stages (dominated by vascular plants).Synthesis. Our findings highlight the fundamental role of dominant plants in controlling the spatial turnover in ecosystem functions, and suggest that accelerated succession under current climate warming may increase bacterial β‐diversity but decrease abiotic heterogeneity, thereby leading to both increases (e.g. regarding functions related to microbial biomass) and decreases (e.g. regarding functions related to nutrient availability) in β‐multifunctionality and hence the spatial turnover in levels of ecosystem functioning. [ABSTRACT FROM AUTHOR]

Abstract: Facilitation has been recognized as an important biotic interaction driving community structure during the recent two decades, such as the integration of facilitation into competition-based community assembly theories, such as the neutral theory of community assembly, is now an emergent task for ecologists. We used an individual-based spatially explicit model to evaluate the impacts of facilitation on the diversity and structure of the neutral community. We found that facilitation promotes neutral community species coexistence and diversity by two kinds of mechanisms, one related to the abiotic environment and the other to biotic interactions. First, facilitation increased species abundances by ameliorating the abiotic environmental conditions, thus reducing species stochastic extinctions at harsh environmental conditions. Second, facilitation played a role as a stabilizing mechanism through “heterospecific density dependence”, resulting in a negative relationship between species fitness and relative abundance. On the other hand, facilitation also has a counteracting negative impact on neutral community diversity through inhibiting colonization of new species from the meta-community by amplifying the “dilution effects”. This negative impact of facilitation overwhelmed its positive impact which caused the reduction of neutral community diversity from low to intermediate environmental severity levels. By comparing the neutral community with the niche-structured community, our results indicated that the negative effect of facilitation on community diversity seems to be a general phenomenon which needs further explorations. [Copyright &y& Elsevier]

Among numerous mechanisms shaping the unimodal relationship between diversity and community biomass, the trade-off model of 'CRS' theory is the most famous one. However, recent researches indicate that this relationship may also emerge under the neutral model where all species are identical with each other. By using an individual-based spatially-explicit model, we evaluated the underlying mechanisms shaping this curve for both models under different disturbance levels. We found unimodal relationships emerged for both models at low and medium disturbance levels; the richness for the trade-off community was lower than the neutral community for most of the environment severity levels, especially at the benign environment due to the strong competitive exclusions among species. Whereas under high disturbance level, the positive relationships emerged for both models; both communities had similar richness with their curves nearly overlapped with each other, that is, because the high disturbance intensity strongly decreased the competitive exclusions within the trade-off community. Our results indicate that although the underlying mechanisms are totally different, both models will produce the similar relationship between diversity and community biomass under different disturbance levels. [ABSTRACT FROM AUTHOR]

Objective A previous study found that the tyrosine phosphorylation of endophilin A2 (Endo II) was responsible for increase surface expression of MT1-MMP and ECM degradation; however, there is little information about whether Endo II could influence membrane estrogen receptors (mERs) and its functions. Materials and methods In the present study, Human umbilical vein endothelial cells (HUVECs) were treated with E2, PPT, DPN, ICI 182780, Endo siRNA or negative control siRNA, and the biological behavior of the treated cells was observed. The mice were randomly divided into AAV-control-shRNA + Ach, AAV-Endo II-shRNA + Ach, AAV-control-shRNA + E2, AAV-Endo II-shRNA + E2 groups and the thoracic aorta were isolated, cut into 2-mm rings, then the wall tension was detected. Results We found that 17β-Estradiol (E2) enhanced mERα protein level, which was further increased after knocking down Endo II, the mechanism maybe involved in E2-induced tyrosine phosphorylation of Endo II. In addition, we also observed that Endo II blocked the activation of Akt, ERK1/2 and eNOS signaling in HUVECs treated with E2. E2 induced vasodilation was significantly increased by silencing of Endo II expression. Conclusion Our study provided a sound basis to selective modulate Endo II for E2's nongenomic pathway, which can be benefit for cardiovascular system. [ABSTRACT FROM AUTHOR]

Objectives: To visualize and quantitatively assess regional lung function of survivors of COVID-19 who were hospitalized using pulmonary free-breathing 1H MRI. Methods: A total of 12 healthy volunteers and 27 COVID-19 survivors (62.4 ± 8.1 days between infection and image acquisition) were recruited in this prospective study and performed chest 1H MRI acquisitions with free tidal breathing. Then, conventional Fourier decomposition ventilation (FD-V) and global fractional ventilation (FVGlobal) were analyzed. Besides, a modified PREFUL (mPREFUL) method was developed to adapt to COVID-19 survivors and generate dynamic ventilation maps and parameters. All the ventilation maps and parameters were analyzed using Student's t-test. Pearson's correlation and a Bland-Altman plot between FVGlobal and mPREFUL were analyzed. Results: There was no significant difference between COVID-19 and healthy groups regarding a static FD-V map (0.47 ± 0.12 vs 0.42 ± 0.08; p =.233). However, mPREFUL demonstrated lots of regional high ventilation areas (high ventilation percentage (HVP): 23.7% ± 10.6%) existed in survivors. This regional heterogeneity (i.e., HVP) in survivors was significantly higher than in healthy volunteers (p =.003). The survivors breathed deeper (flow-volume loop: 5375 ± 3978 vs 1688 ± 789; p =.005), and breathed more air in respiratory cycle (total amount: 62.6 ± 19.3 vs 37.3 ± 9.9; p <.001). Besides, mPREFUL showed both good Pearson's correlation (r = 0.74; p <.001) and Bland-Altman consistency (mean bias = −0.01) with FVGlobal. Conclusions: Dynamic ventilation imaging using pulmonary free-breathing 1H MRI found regional abnormity of dynamic ventilation function in COVID-19 survivors. Key Points: • Pulmonary free-breathing1H MRI was used to visualize and quantitatively assess regional lung ventilation function of COVID-19 survivors. • Dynamic ventilation maps generated from1H MRI were more sensitive to distinguish the COVID-19 and healthy groups (total air amount: 62.6 ± 19.3 vs 37.3 ± 9.9; p <.001), compared with static ventilation maps (FD-V value: 0.47 ± 0.12 vs 0.42 ± 0.08; p =.233). • COVID-19 survivors had larger regional heterogeneity (high ventilation percentage: 23.7% ± 10.6% vs 13.1% ± 7.9%; p =.003), and breathed deeper (flow-volume loop: 5375 ± 3978 vs 1688 ± 789; p =.005) than healthy volunteers. [ABSTRACT FROM AUTHOR]

Background:Conditionality in the occurrence or strength of interactions among species yields insight into the relative importance of different ecological factors and provides a deeper understanding of the mechanisms through which organisms interact. Aims:We explored light-dependent conditionality of the allelopathic effects ofCentaurea stoebe, an exotic invasive forb in North America, onKoeleria macrantha, a North American native bunchgrass. Methods:We compared the total biomass ofK. macranthacompeting withC. stoebein high- and low-light treatments and in substrate with and without activated carbon. Results:Koeleriabiomass did not differ in low- and high-light treatments when grown alone and was highly suppressed byC. stoebein both low and high light; however, high-light activated carbon treatments designed to ameliorate root-mediated allelopathic effects resulted in an almost seven-fold increase inKoeleriamass in comparison to no carbon treatments. Activated carbon had significant but much weaker positive effects in low light. Activated carbon had no effect onKoeleriain the absence ofC. stoebe. Conclusions:Other research shows thatC. stoebedecreases sharply in abundance under tree canopies, and under canopies its typically strong competitive effects on natives in open grasslands are reduced. Our results provide a hypothesis for these patterns, suggest a possible mechanism for light-dependent conditionality in the way plants interact, and suggest thatin vivogreenhouse experiments at moderate light levels may provide conservative evidence for allelopathy. [ABSTRACT FROM AUTHOR]

Abstract: Newcastle disease virus (NDV) is an avian virus that is attenuated in primates and is a potential vaccine vector for human use. We evaluated NDV as a vector for expressing selected antigens of the Lyme disease pathogen Borrelia burgdorferi. A series of recombinant NDVs were generated that expressed intracellular or extracellular forms of two B. burgdorferi antigens: namely, the basic membrane protein A (BmpA) and the outer surface protein C (OspC). Expression of the intracellular and extracellular forms of these antigens was confirmed in cultured chicken cells. C3H or Balb/C mice that were immunized intranasally with the NDV vectors mounted vigorous serum antibody responses against the NDV vector, but failed to mount a robust response against either the intracellular or extracellular forms of BmpA or OspC. By contrast, a single immunization of hamsters with the NDV vectors via the intranasal, intramuscular, or intraperitoneal route resulted in rapid and rigorous antibody responses against the intracellular or extracellular forms of BmpA and OspC. When groups of hamsters were separately inoculated with various NDV vectors and challenged with B. burgdorferi (108 cells/animal), immunization with vector expressing either intracellular or extracellular BmpA was associated with a significant reduction of the pathogen load in the joints. Taken together, our studies highlighted the importance of NDV as vaccine vector that can be used for simple yet effective immunization of hosts against bacterial infections including Lyme disease. [Copyright &y& Elsevier]

Abstract: Complete genome sequences were determined for two strains of avian paramyxovirus serotype 6 (APMV-6): the prototype Hong Kong (HK) strain and a more recent isolate from Italy (IT4524-2). The genome length of strain HK is 16236 nucleotide (nt), which is the same as for the other two APMV-6 strains (FE and TW) that have been reported to date, whereas that of strain IT4524-2 is 16230 nt. The length difference in strain IT4524-2 is due to a 6-nt deletion in the downstream untranslated region of the F gene. All of these viruses follow the “rule of six”. Each genome consists of seven genes in the order of 3′N-P-M-F-SH-HN-L5′, which differs from other APMV serotypes in containing an additional gene encoding the small hydrophobic (SH) protein. Sequence comparisons revealed that strain IT4524-2 shares an unexpectedly low level of genome nt sequence identity (70%) and aggregate predicted amino acid (aa) sequence identity (79%) with other three strains, which in contrast are more closely related to each other with nt sequence 94–98% nt identity and 90–100% aggregate aa identity. Sequence analysis of the F-SH-HN genome region of two other recent Italian isolates showed that they fall in the HK/FE/TW group. The predicted signal peptide of IT4524-2 F protein lacks the N-terminal first 10 aa that are present in the other five strains. Also, the F protein cleavage site of strain IT4524-2, REPR↓L, has two dibasic aa (arginine, R) compared to the monobasic F protein cleavage site of PEPR↓L in the other strains. Reciprocal cross-hemagglutination inhibition (HI) assays using post-infection chicken sera indicated that strain IT4524-2 is antigenically related to the other APMV-6 strains, but with 4- to 8-fold lower HI tiers for the test sera between strain IT4524-2 and the other APMV-6 strains. Taken together, our results indicated that the APMV-6 strains represents a single serotype with two subgroups that differ substantially based on nt and aa sequences and can be distinguished by HI assay. [Copyright &y& Elsevier]

Abstract: The complete genome sequence of avian paramyxovirus serotype 7 (APMV-7) prototype strain dove/Tennessee/4/75 was determined. The genome size is 15,480 nucleotides (nt) long and follows the “rule of six”. The genome contains six non-overlapping genes in the order of 3′-N-P/V/W-M-F-HN-L-5′. The 3′-leader and 5′-trailer sequences of the genome are 55 and 127nt long, respectively. The first 12nt of the leader and trailer sequences are complementary to each other. The viral genes are flanked by highly conserved gene-start (GS) and gene-end (GE) transcription signals, and in addition the 3′-leader sequence contains a sequence (35AAUUAUUUUUU45) that is identical to the GE signal present at two of the genes. The genes are separated by intergenic sequences (IGS) ranging between 11 and 70nt. The phosphoprotein (P) gene contains a conserved RNA editing site (3′-UUUUUCCC-5′) presumed to be involved in the production of V and W proteins. The viral fusion (F) protein has a single basic amino acid at the putative cleavage site (101TLPSSR↓F107); however, the virus did not require exogenous protease for in vitro replication. The virus grew in only a few established cell lines, indicating a restricted host range. Sequence alignment and phylogenetic analysis of the predicted amino acid sequence of APMV-7 proteins with the cognate proteins of the viruses of all five genera of the family Paramyxoviridae showed that APMV-7 is more closely related to APMV-2, -6, -8 than to APMV-1, -3, -4 and -9. The mean death time in embryonated chicken eggs was found to be more than 144h, indicating APMV-7 to be avirulent for chickens. [Copyright &y& Elsevier]