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Glioblastoma multiforme (GBM) is a fatal central nervous system tumor without effective treatment. Chemotherapeutic agents are mainstays in the treatment of glioblastoma. However, the effectiveness of these is seriously hindered by poor blood-brain-barrier (BBB) penetrance and tumor targeting, together with short biological half-life. Improved chemotherapy is thus urgently needed for GBM. Multifunctional nanoparticle delivery systems offer much promise in overcoming current limitations. Accordingly, a multifunctional biomimetic nanomedicine is developed by functionalizing the surface of red blood cell membranes (RBCms) with angiopep-2 and loading pH-sensitive nanoparticles (polymer, doxorubicin (Dox), and lexiscan (Lex)) using the functionalized cell membrane to generate the novel nanomedicine, Ang-RBCm@NM-(Dox/Lex). The studies toward orthotopic U87MG human glioblastoma tumor-bearing nude mice show that the Ang-RBCm@NM-(Dox/Lex) nanomedicine has much improved blood circulation time, superb BBB penetration, superior tumor accumulation and retention. Moreover, effective suppression of tumor growth and significantly improved medium survival time are also observed after Ang-RBCm@NM-(Dox/Lex) treatment. The results show that this biomimetic nanoplatform can serve as a flexible and powerful system for GBM treatment which can be readily adapted for the treatment of other central nervous system (CNS) disorders.

We have developed an unprecedented approach for the synthesis of transient 1-phosphafulvenes through three component reactions of phospholes. The generation of 1-phosphafulvenes was demonstrated by in situ [6 + 4] cycloaddition with 2H-phospholes and [6 + 6] self-dimerization. The [6 + 4] and [6 + 6] reaction pathway could be modulated by the starting ketones and aldehydes. The construction of 1-phosphafulvenes is illustrated by a proposed mechanism combining nucleophilic addition of phospholide to the iminium or isomerized azomethine ylide and a [1,5]-shift of phosphole.

The coordination chemistry of 1-phosphafulvenes was investigated by employing their [6 + 4] adducts or α-C2-bridged biphospholes as a precursor. Unbridged phosphacymantrenes arise from 1-phosphafulvenes via proton abstraction. α-C2-bridged biphosphacymantrenes are probably yielded by the reductive coupling of 1-phosphafulvene with Mn2(CO)10. The coordination behavior of 1-phosphafulvenes is comparable to that of pentafulvenes, which again demonstrates the phosphorus-carbon analogy in low-coordinate organophosphorus chemistry.

Aiming to understand fundamentally the alloying effects on the oxidation behaviors of Nb alloys, we combined the first-principles density functional theory and Kinetic Monte Carlo simulations to calculate systematically the binding energies, energy barriers, and diffusion coefficients of oxygen in Nb-X alloys where X = thirty 3d, 4d, and 5d transition metal (TM) elements plus Al and Si in this work. According to the calculated binding energies and energy barriers, we classify the alloying effects into three categories: (a) local short-range trapping effects (X = V, Ti, Cr, Y, Zr, and Hf); (b) local long-range trapping effects (X = Si and Ru); (c) non-local non-trapping effects (X = Mo, W, and Al). Our results show that the solute elements with the short-range trapping effects at near regions had the most effective reduction effects on the O diffusion coefficients while the long-range trapping effects and the non-local effects are less significant but non-negligible. Specifically, the reduction effects of the partial studied alloying elements decrease in the order of Y> V> Ti> Si> Cr> Zr> Hf> Al> Mo> Ru> W. For all the studied 30 TM elements, the diffusion coefficients were calculated for O at the near regions of the solute atoms and their trends were discussed. These intrinsic alloying effects on the oxygen diffusion in Nb alloys provide the theoretical evidence for the rational composition design of oxidation-resistant Nb alloys.

An unusual chemoselective 1,1-addition of α-C2-bridged biphospholes to terminal alkynes is reported. The developed protocol provides simple access to the unknown 1,3-diphosphepines, which has poten...

In Saccharomyces cerevisiae under conditions of nutrient stress, meiosis precedes the formation of spores. Although the molecular mechanisms that regulate meiosis, such as meiotic recombination and nuclear divisions, have been extensively studied, the metabolic factors that determine the efficiency of sporulation are less understood. Here, we have directly assessed the relationship between metabolic stores and sporulation in S. cerevisiae by genetically disrupting the synthetic pathways for the carbohydrate stores, glycogen (gsy1/2Δ cells), trehalose (tps1Δ cells), or both (gsy1/2Δ and tps1Δ cells). We show that storage carbohydrate-deficient strains are highly inefficient in sporulation. Although glycogen and trehalose stores can partially compensate for each other, they have differential effects on sporulation rate and spore number. Interestingly, deletion of the G1 cyclin, CLN3, which resulted in an increase in cell size, mitochondria and lipid stores, partially rescued meiosis progression and spore ascus formation but not spore number in storage carbohydrate-deficient strains. Sporulation efficiency in the carbohydrate-deficient strain exhibited a greater dependency on mitochondrial activity and lipid stores than wild-type yeast. Taken together, our results provide new insights into the complex crosstalk between metabolic factors that support gametogenesis.

The effect of cropping regime on nitrogen (N) uptake in two coexisting plant grass species (Avena sativa and Agropyron cristatum) was investigated. The two grass species were cultivated by monocropping or intercropping. 15N-labeling was used to examine N uptake of NH4+ versus NO3− at 0–5 cm and 5–15 cm soil depths. The aboveground and total biomass of intercropped A. sativa was 1.3 times greater than monocropped A. sativa. The biomass of A. cristatum did not change between cropping systems. In the 0–5 cm soil layer, uptake of NO3− by A. sativa was 0.5 times less in the intercropped system than in the monocropped system, whereas uptake of NO3− by A. cristatum was 2.0 times more in the intercropped system. In the 5–15 cm depth, intercropping did not change N uptake by A. sativa but decreased NO3− uptake to 0.6 times by A. cristatum. Complementarity in N uptake between A. sativa and A. cristatum in the upper 0–5 cm soil layer is conducive to biomass accumulation. Intercropped A. sativa and A. cristatum does not compete strongly for soil resources and can alter their N uptake patterns to optimize biomass production.

The Novel Defense Hypothesis predicts that introduced plants may possess novel allelochemicals which act as a defense against native generalist enemies. Here, we aim to test if the chemicals involved in allelopathy in the invasive plant Wedelia trilobata can contribute to higher resistance against generalist herbivore and pathogen enemies by comparing with its native congener W. chinensis in controlled laboratory conditions. The allelopathic effects of the leaf extract from W. trilobata on the generalist enemies were also assessed. We showed that the larvae of two moth species preferred W. chinensis over W. trilobata. The growth rate of larvae feeding on W. trilobata leaves was significantly lower than those feeding on W. chinensis leaves. When detached leaves were inoculated with phytopathogens, the infected leaf area of W. trilobata was significantly smaller than that of W. chinensis. In addition, the leaf extract of W. trilobata also effectively inhibited the growth of the larvae and the mycelial growth of the phytopathogens. Our results indicate that the defenses of invasive W. trilobata against generalist herbivore and pathogen enemies are stronger than that of its native congener, which may be attributed to the allelopathic effects. This study provides novel insights that can comprehensively link the Novel Defense, Behavioral Constraint and Enemy Release hypotheses. These combined hypotheses would explain how invasive plants escape from their natural specialist enemies, where their allelopathic chemicals may deter herbivorous insects and inhibit pathogen infection.

The fungal products dibenzodioxocinones promise a novel class of inhibitors against cholesterol ester transfer protein (CEPT). Knowledge as to their biosynthesis is scarce. In this report, we characterized four more dibenzodioxocinones, which along with a previously described member pestalotiollide B, delimit the dominant spectrum of secondary metabolites in P. microspora. Through mRNA-seq profiling in gα1Δ, a process that halts the production of the dibenzodioxocinones, a gene cluster harboring 21 genes including a polyketide synthase, designated as pks8, was defined. Disruption of genes in the cluster led to loss of the compounds, concluding the anticipated role in the biosynthesis of the chemicals. The biosynthetic route to dibenzodioxocinones was temporarily speculated. This study reveals the genetic basis underlying the biosynthesis of dibenzodioxocinone in fungi, and may facilitate the practice for yield improvement in the drug development arena.

Background Lutein ester (LE) is an important carotenoid fatty acid ester. It is a form in which lutein is present in nature and is produced by free non-esterification and fatty acid esterification. LE is one of the safe sources of lutein. Increasing lutein intake can prevent and treat age-related macular degeneration. In addition, it can effectively inhibit gastric cancer, breast cancer, and esophageal cancer. However, the poor aqueous solubility of LE has impeded its clinical applications. Objective The objective of this study was to prepare lutein ester nanoparticles (LE-NPs) by liquid antisolvent precipitation techniques to improve the bioavailability of LE in vivo and improve eye delivery efficiency. Materials and methods The physical characterization of LE-NPs was performed, and their in vitro dissolution rate, in vitro antioxidant capacity, in vivo bioavailability, tissue distribution, and ocular pharmacokinetics were studied and evaluated. Results The LE freeze-dried powder obtained under the optimal conditions possessed a particle size of ~164.1±4.3 nm. The physical characterization analysis indicated the amorphous form of LE-NPs. In addition, the solubility and dissolution rate of LE-NPs in artificial gastric juice were 12.75 and 9.65 times that of the raw LE, respectively. The bioavailability of LE-NPs increased by 1.41 times compared with that of the raw LE. The antioxidant capacity of LE-NPs was also superior to the raw LE. The concentration of lutein in the main organs of rats treated with the LE-NPs was higher than that in rats treated with the raw LE. The bioavailability of LE-NPs in rat eyeballs was found to be 2.34 times that of the original drug. Conclusion LE-NPs have potential application as a new oral pharmaceutical formulation and could be a promising eye-targeted drug delivery system.

The ginkgo biloba extract (GBE) nanoparticles were successfully prepared by adopting the liquid anti‐solvent precipitation (LASP) method to enhance the antioxidant activity and oral bioavailability of GBE. Under the optimum preparation conditions, the particle size of GBE nanoparticles had reached 76.90 nm. Moreover, the antioxidant activity and intestinal transmittance of GBE nanoparticles were tested before and after the simulated in vitro digestion, which were both significantly higher than that of raw GBE. Significantly, the AUC₍₀→ₜ₎ value of flavonoids and terpene lactones in GBE nanoparticles were 2.20 and 2.24 times of that in raw GBE, respectively. What cannot be ignored was that the residual amount of ethanol and n‐hexane meets the safety standards for food.

It is frequently assumed that species capable of fast nitrogen (N) acquisition under different N‐availability conditions should have a higher establishment success after their introduction into new regions. However, few experimental studies have explicitly tested this. Our multispecies experiment tested whether global naturalization success of plant species native to Central Europe is related to a high N‐acquisition ability. We selected 41 common herbaceous species native to Germany that have all become naturalized, and thus been introduced, elsewhere. Twenty‐two of these species are widely naturalized and 19 are less widely naturalized. We grew the 41 grassland species, sampled in Germany, under low and high N‐conditions in a greenhouse experiment, and assessed their N‐acquisition abilities. Although the widely naturalized species grew faster on average, they had a significantly lower N‐uptake rate than the less widely naturalized ones. The widely naturalized species, however, had a marginally significantly higher root‐mass fraction. Despite these differences, the total plant N‐content did on average not differ between the two groups of species. However, N‐addition tended to increase the total plant N‐content more for the widely naturalized species than for the less widely naturalized species. Nitroge addition also increased biomass production and N‐uptake rate, and decreased the root‐mass fraction of plants, but these responses did not differ between widely and less widely naturalized species. We conclude that although fast‐growing species tend to have a higher global naturalization success than slow‐growing species, the naturalization success of plants is not necessarily related to a high N‐acquisition ability. A plain language summary is available for this article.

The Hot Universe Baryon Surveyor (HUBS) mission is proposed to study "missing" baryons in the universe. Unlike dark matter, baryonic matter is made of elements in the periodic table, and can be directly observed through the electromagnetic signals that it produces. Stars contain only a tiny fraction of the baryonic matter known to be present in the universe. Additional baryons are found to be in diffuse (gaseous) form, in or between galaxies, but a significant fraction has not yet been seen. The latter (missing baryons) are thought to be hiding in low-density warm-hot ionized medium (WHIM), based on results from theoretical studies and recent observations, and be distributed in the vicinity of galaxies (i.e., circum-galactic medium) and between galaxies (i.e., intergalactic medium). Such gas would radiate mainly in the soft X-ray band and the emission would be very weak, due to its very low density. HUBS is optimized to detect the X-ray emission from the hot baryons in the circum-galactic medium, and thus fill a void in observational astronomy. The goal is not only to detect the missing baryons, but to characterize their physical and chemical properties, as well as to measure their spatial distribution. The results would establish the boundary conditions for understanding galaxy evolution. Though highly challenging, detecting missing baryons in the intergalactic medium could be attempted, perhaps in the outskirts of galaxy clusters, and could shed significant light on the large-scale structures of the universe. The current design of HUBS will be presented, along with the status of technology development., Comment: 12 pages, 7 figures, Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray, eds. J.A. den Herder, S. Nikzad, & K. Nakazawa, Proc. of SPIE Vol. 11444, 114442S

Bombus pyrosoma is one of the most abundant bumblebee species in China, with a distribution range of very varied geomorphology and vegetation, which makes it an ideal pollinator species for research into high-altitude adaptation. Here, we sequenced and assembled transcriptomes of B. pyrosoma from the low-altitude North China Plain and the high-altitude Tibet Plateau. Subsequent comparative analysis of de novo transcriptomes from the high- and low-altitude groups identified 675 common upregulated genes (DEGs) in the high-altitude B. pyrosoma. These genes were enriched in metabolic pathways and corresponded to enzyme activities involved in energy metabolism. Furthermore, according to joint analysis with comparative metabolomics, we suggest that the metabolism of coenzyme A (CoA) and the metabolism and transport of energy resources contribute to the adaptation of high-altitude B. pyrosoma. Meanwhile, we found many common upregulated genes enriched in the Toll and immune deficiency (Imd)signaling pathways that act as important immune defenses in insects, and hypoxia and cold temperatures could induce the upregulation of immune genes in insects. Therefore, we suppose that the Toll and Imd signaling pathways also participated in the high-altitude adaptation of B. pyrosoma. Like other organisms, we suggest that the high-altitude adaptation of B. pyrosoma is controlled by diverse mechanisms.

Allelopathy (i.e. chemical interactions between plants) is known to affect individual performance, community structure and plant invasions. Yet, a quantitative synthesis is lacking. Here, we performed a meta-analysis of 384 studies that measured allelopathic effects of one species (allelopathy plant) on another species or itself (test plant). Overall, allelopathy reduced plant performance by 25%, but the variation in allelopathy was high. The type of method affected the allelopathic effect: compared to leachates, allelopathy was more negative when residues of allelopathy plants were applied, and less negative when soil conditioned by allelopathy plants was applied. The negative effects of allelopathy diminished with study duration, and increased with concentrations of leachates or residues. Although allelopathy was not significantly related to lifespan, life form or domestication of the interacting plants, it became more negative with increasing phylogenetic distance. Moreover, native plants suffered more from leachates of naturalised alien plants than from leachates of other native plants. Our synthesis reveals that allelopathy could contribute to success of alien plants. The negative relationship between phylogenetic distance and allelopathy indicates that allelopathy might contribute to coexistence of closely related species (i.e. convergence) or dominance of single species. published

Peptidoglycan recognition proteins (PGRPs) play an important role in the defense against invading microbes via the recognition of the immunogenic substance peptidoglycan (PGN). Bees possess fewer PGRPs than Drosophila melanogaster and Anopheles gambiae but retain two important immune pathways, the Toll pathway and the Imd pathway, which can be triggered by the recognition of Dap-type PGN by PGRP-LCx with the assistance of PGRP-LCa in Drosophila. There are three isoforms of PGRP-LC including PGRP-LCx, PGRP-LCa and PGRP-LCy in Drosophila. Our previous study showed that a single PGRP-LC exists in bumblebees. In this present study, we prove that the bumblebee Bombus lantschouensis PGRP-LC (Bl-PGRP-LC) can respond to an infection with Gram-negative bacterium Escherichia coli through binding to the Dap-type PGNs directly, and that E. coli infection induces the quick and strong upregulation of PGRP-LC, abaecin and defensin. Moreover, the Bl-PGRP-LC exhibits a very strong affinity for the Dap-type PGN, much stronger than the affinity exhibited by the PGRP-LC from the more eusocial honeybee Apis mellifera (Am-PGRP-LC). In addition, mutagenesis experiments showed that the residue His390 is the anchor residue for the binding to the Dap-type PGN and forms a hydrogen bond with MurNAc rather than meso-Dap, which interacts with the anchor residue Arg413 of PGRP-LCx in Drosophila. Therefore, bumblebee PGRP-LC possesses exclusive characteristics for the immune response among insect PGRPs.

Small interfering RNA (siRNA) has been considered as a highly promising therapeutic agent for human cancer treatment including glioblastoma (GBM), which is a fatal disease without effective therapy methods. However, siRNA-based GBM therapy is seriously hampered by a number of challenges in siRNA brain delivery including poor stability, short blood circulation, low blood-brain barrier (BBB) penetration, and tumor accumulation, as well as inefficient siRNA intracellular release. Herein, an Angiopep-2 (Ang) functionalized intracellular-environment-responsive siRNA nanocapsule (Ang-NCss (siRNA)) is successfully developed as a safe and efficient RNAi agent to boost siRNA-based GBM therapy. The experimental results demonstrate that the developed Ang-NCss (siRNA) displays long circulation in plasma, efficient BBB penetration capability, and GBM accumulation and retention, as well as responsive intracellular siRNA release due to the unique design of small size (25 nm) with polymeric shell for siRNA protection, Ang functionalization for BBB crossing and GBM targeting, and disulfide bond as a linker for intracellular-environment-responsive siRNA release. Such superior properties of Ang-NCss (siRNA) result in outstanding growth inhibition of orthotopic U87MG xenografts without causing adverse effects, achieving remarkably improved survival benefits. The developed siRNA nanocapsules provide a new strategy for RNAi therapy of GBM and beyond.

While most alien species fail to establish, some invade native communities and become widespread. Our understanding of invasion success is derived mainly from pairwise interactions between aliens and natives, while interactions among more than two species remain largely unexplored. Here, we experimentally tested whether and how a third plant species, either native or alien, affected the competitive outcomes between alien and native plants through its soil legacy. We first conditioned soil with one of ten species (six natives and four aliens) or without plants. We then grew on these 11 soils five aliens and five natives without competition, or with intra- or interspecific competition. We found that aliens were not more competitive than natives when grown on soil conditioned by other natives or on non-conditioned soil. However, aliens were more competitive than natives on soil conditioned by other aliens (that is, invasional meltdown). Soil conditioning did not change competitive outcomes by affecting the strength of competition between later plants. Instead, soil conditioned by aliens pushed competitive outcomes towards later aliens by affecting the growth of aliens less negatively than that of natives. Microbiome analysis verified this finding, as we showed that the soil-legacy effects of a species on later species were less negative when their fungal endophyte communities were less similar, and that fungal endophyte communities were less similar between two aliens than between aliens and natives. Our study reveals invasional meltdown in multispecies communities and identifies soil microorganisms as a driver of the invasion success of alien plants. published

Sixty year ago, Charles Elton posed that species-rich communities should be more resistant to biological invasion. However, still little is known about which processes could drive the diversity-invasibility relationship. Here we examined whether soil-microbes-mediated apparent competition on alien invaders is more negative when the soil originates from multiple native species. We trained soils with five individually grown native species, and used amplicon sequencing to analyze the resulting bacterial and fungal soil communities. We mixed the soils to create trained soils from one, two or four native species. We then grew four alien species separately on these differently trained soils. In the soil-conditioning phase, the five native species built species-specific bacterial and fungal communities in their rhizospheres. In the test phase, it did not matter for biomass of alien plants whether the soil had been trained by one or two native species. However, the alien species achieved 11.7% (95% CI: 3.7% ~ 20.1%) less aboveground biomass when grown on soils trained by four native species than on soils trained by two native species. Our results revealed soil-microbes-mediated apparent competition as a mechanism underlying the negative relationship between diversity and invasibility. published

1.It is frequently thought that global environmental changes, and especially the concomitant changes in environmental variability, could further increase the success of invasive species in native resident communities. However, very few studies explicitly tested this, and it remains unknown whether invasive and non‐invasive alien species respond differently to resource fluctuations in resident communities.2.We grew ten invasive and ten non‐invasive species as target species in pot‐mesocosms with four different synthetic native resident communities under six nutrient treatments differing in overall nutrient availability and temporal fluctuations in nutrient supply (constant low, constant high, gradual increasing, gradual decreasing, single large pulse, multiple smaller pulses). With the exception of plants in the constant low treatment, the plants were supplied the same total amount of nutrients during the experiment. We tested whether high nutrient availability and fluctuations in nutrient supply increased performance of both invasive and non‐invasive alien plants within native resident communities, and whether invasive ones benefited more than non‐invasive ones.3.We found that the increase in biomass in response to nutrient addition was stronger for invasive than for non‐invasive alien species. However, as the native competitors benefited even more from nutrient addition, the relative biomass of the alien target plant species, particularly the non‐invasive ones, decreased. When the nutrient supply gradually increased, biomass of alien targets as well as native competitors decreased compared to the plants in the constant nutrient supply treatment. Surprisingly, when nutrients were supplied as a single large pulse, the absolute and relative biomass of the alien target plants decreased. The reduction in relative biomass was even stronger for invasive than for non‐invasive alien species, and a similar pattern was found when nutrients were supplied as multiple smaller pulses.4.Our results confirm previous findings that invasive alien species benefit more from nutrient addition than non‐invasive alien species. However, in contrast to previous findings, our results suggest that nutrient fluctuations can suppress biomass of alien plants relative to that of natives, at least when the natives are themselves very successful, common species. published

China has experienced an increase in integrated rice-crayfish (Procambarus clarkii) culture (IRCC) in rice paddies. However, whether the current regime degrades phosphorus (P) fertility in rice paddies remains unclear. To assess changes in P fertility, the surface soil (0-20cm) of high-yield rice paddies with 3, 6, and 10 consecutive years of IRCC was sampled in Honghu County in the Jianghan Plain region, China. Adjacent fields planted with long-term rotations of rice and dry-season crops (RRD) were also sampled. Total P (TP), available P (P-a), organic P (P-o) compounds, and P fractions in soils were intensively assessed using chemical digestion, NaHCO3 extraction, P-31 nuclear magnetic resonance, and sequential chemical extraction. IRCC significantly increased organic matter, total nitrogen, TP, Fe(II), and S2- contents of rice paddy soils and nutrient concentrations in the surface water, with a distinct decrease in total Fe and pH. Consecutive IRCC greatly influenced P fertility. Continuous P accumulation in rice paddy soils accelerated greatly, with a mean increase of approximately 43mgkg(-1)yr(-1). P-a was 67% higher after 3years of IRCC, compared with RRD, but 78% lower after 10years. Consecutive IRCC induced a decrease in P-o compounds, with a mean decrease in TPo of approximately 20mgkg(-1)yr(-1). Long-term consecutive IRCC increased transformation of P-a, Fe(II)-P, and P-o into Ca-P and Fe(III)-P, increasing mean Ca-P and Fe(III)-P concentrations by approximately 69 and 7mgkg(-1)yr(-1), respectively. Our results suggested that long-term consecutive IRCC degrades P fertility in rice paddies, and implementing IRCC in high-yield rice paddies is not recommended.

This study aims to extract and purify flavonoids from licorice by an efficient and environmentally friendly approach. The ultrasonic microwave-assisted micellar extraction (UMAME) method was used to extract licorice flavonoids (LFs). The optimal extraction parameters including lauryl sodium sulfate concentration, microwave power, solvent-material ratio and extraction time were investigated by a single factor method and response surface methodology. The extraction rate of LFs was up to 3.65% under the optimal conditions. The extraction solution was pretreated with ethyl acetate and the purity of raw LFs reached 36.47%. The purity of raw LFs was increased from 36.47% to 90.32% by metal complex method and antisolvent recrystallization method. The antioxidant test results showed that the finally purified LFs with an IC50 value of 3.519 μg/mL had a strong scavenging ability on DPPH free radical.

Melatonin (MLT) is a small molecule with low water solubility and high permeability. According to the Biopharmaceutics Classification System, MLT is a class II drug exhibiting a very short half-life and minimal and variable bioavailability. This work aimed to establish a delivery system composed of an enteric MLT nanosphere with favorably controlled and sustained release characteristics superior to those of raw MLT. The nanosphere was composed of hydroxypropyl methylcellulose phthalate (HP55) and silica (SiO2) with MLT. As a carrier, SiO2 contains numerous surface pores with high adsorption capacity advantageous for permeability and slow release. HP55 is a good enteric coating material. MLT-loaded SiO2 was obtained through adsorption in acetone solution. A MLT-loaded SiO2 coated with HP55 (MLT-SiO2-HP55) nanosphere was prepared via desolvation. The characteristics of this nanosphere were analyzed through transmission electron microscopy, Brunauer-Emmett-Teller surface area analysis, diffuse reflectance infrared Fourier transform spectroscopy, X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. Results show that MLT was loaded mostly in the pores of SiO2. HP55 was coated on a large portion of MLT-SiO2. In vitro release studies revealed that the release rate of MLT from MLT-SiO2 was higher than that of raw MLT in simulated gastric fluid (SGF). The amount of MLT released from MLT-SiO2-HP55 in SGF was lower than that released from simulated intestinal fluid because of HP55 coated on MLT-SiO2. In vivo evaluation demonstrated the controlled drug release of MLT-SiO2-HP55 in rats. Compared with raw MLT, MLT-SiO2-HP55 prolonged peak time (Tmax) from 15min to 30min and increased peak concentration (Cmax) from 168.86ng/mL to 383.71ng/mL. The corresponding area under the curve (AUC) of MLT-SiO2-HP55 was 3.5 times higher than that of raw MLT. This finding illustrated the sustained release of MLT-SiO2-HP55. Our in vitro release and in vivo absorption studies indicated that the proposed preparation of MLT-SiO2-HP55 is an effective method to facilitate the controlled and sustained release of MLT with enhanced bioavailability.

Nitrogen (N) deposition and land use are likely to alter plant phenology, with subsequent effects on community structure and ecosystem function. Phenological responses of three early-flowering species, Anemone trullifolia var. linearis, Caltha scaposa, and Trollius farreri to N addition and hay mowing were investigated in a Tibetan alpine meadow over three years. N addition significantly delayed the first flowering time of A. trullifolia var. linearis (by 11.7 days) and C. scaposa (by 11.1 days), but did not affect that of T. farreri. Mowing prolonged the first flowering time and first fruiting time by 4.7 and 7.4 days across all three species. Significant interactions between mowing and N addition on reproductive phenology characteristics were detected. Mowing induced changes in the first and last flowering times were 6.5 and 4.3 days earlier in the N addition plots than those in the N non-addition plots. The changes in reproductive time were mainly attributed to the variations in standing litter in each treatment, i.e. reproductive phenology (timing of flowering and fruiting) was positively associated with litter accumulation. Our results indicate that N deposition and land use can affect plant phenology by changing the accumulation of standing litter in Tibetan alpine meadows.

For the conservation of wild pollinators, instead of surveying the whole community, one or more indicator species can be used as monitoring targets for long-term conservation. China, the richest country in terms of bumblebee species with 125 species, was selected here to investigate the indicator species of the different biogeographic regions of bumblebees. Four principal biogeographic regions of bumblebee species, i.e., South China, North-Northeast China (North China), the Mongolian Plateau and surrounding mountains (Mongolian Plateau) and the Tibetan Plateau and surrounding mountains (Tibetan Plateau), were revealed by Ward's agglomerative cluster analysis. The role of climatic factors in defining the biogeographic regions was found to be greater than those of topographical factors and their joint effects. We found that 14, 13, 12 and 12 species were associated with the regions of South China, North China, the Mongolian Plateau and the Tibetan Plateau, respectively. In addition, among these species, seven (Bombus atripes, B. bicoloratus, B. breviceps, B. eximius, B. flavescens, B. montivagus and B. trifasciatus), five (B. deuteronymus, B. patagiatus, B. pseudobaicalensis, B. tricornis and B. ussurensis), ten (B. armeniacus, B. confusus, B. cryptarum, B. cullumanus, B. hortorum, B. muscorum, B. ruderarius, B. soroeensis, B. subterraneus and B. terrestris) and four species (B. kashmirensis, B. personatus, B. rufofasciatus and B. waltoni) were identified as important indicator species for South China, North China, the Mongolian Plateau and the Tibetan Plateau, respectively. Furthermore, we identified specific areas for targeted bumblebee diversity monitoring in each region. This study highlights the bioregionalization and the identification of indicator species of bumblebee pollinators for long-term monitoring in conservation.

A large-load magnetic levitation gravity compensator is proposed in this paper, which can be used as the passive support scheme for the large optical facilities to achieve the ground testing. The magnetic levitation gravity compensator is composed of three layers of 2D PM array, the middle of which is the mover. The analytical model is built based on the magnetic charge model. Furthermore, an improved charge model considering the actual working point of PM is presented and verified by the 3D finite element simulation. Finally, the influence analysis of the main parameters such as the pole pitch, pole-arc coefficient, PM thickness and air gap on the levitation force and levitation force ripple are achieved.

In an appropriate electrochemical environment, the discrete thermal electron emission could be induced in the micro area due to the uneven distribution of electron flux on the anode surface. Thus an oxygen molecule could be ionized at the liquid-solid interface after collision, and then oxygen plasma with distribution characteristics would be formed. The plasma electrolytic oxidation (PEO) could happen at the liquid-solid interface. In this work, the low carbon steel was used to study the deburring process by PEO at a high frequency (70000 Hz) pulse DC mode. Its burr height H from 3.23 mm to 0.04 mm was removed to form a smooth surface within 6 min. The values of corrosion potential and current density for the untreated sample were −0.667 V and 6.735×10−5 A/cm2, respectively. But for the treated sample, the corrosion potential and current density were relatively lower, −0.354 V and 1.19×10−7 A/cm2. Therefore, PEO was expected to be a new deburring method of carbon steel for the material processing field.

1-Phosphafulvenes can be easily generated by dissociation of dimers resulting from the reaction of phospholes with aldimines. As electron-rich partners, they act as 4π phosphadienic systems toward alkenes and alkynes in [4 + 2] cycloaddition reactions. As electron-poor partners, they act either as 2π systems toward conjugated dienes in [2 + 4] cycloaddition reactions via their P═C double bond or as 6π systems toward phosphadienes in [6 + 4] cycloaddition reactions.

It is known that 7-epitaxol has much stronger cytotoxicity than taxol does. However, the content of 7-epitaxol in yew is much less than taxol, which makes it more costly to obtain. We describe here a method to effectively convert taxol to 7-epitaxol. The key condition for reaction needs NaHCO3 in solvent acetonitrile (ACN). The conversion rate can be over 82%.

A space 100 mW@4.5 K JT cooler is designed, manufactured and experimentally tested by our laboratory. The multi-orifice JT element is proposed to improve the performance of the JT loop. And compared to single orifice, the multi-orifice JT elements perform better. Cooling power of 100.3 mW@4.55 K is achieved when JT element is 4 * 20 μm orifice and supply pressure is 2.0 MPa in open loop experiment. In closed loop experiment, three oil-free linear compressors are used to drive the JT loop, and cooling capacity 102.3 mW at 5.02 K is achieved. This JT cooler will be the potential cryocooler for the future space detectors working at 4.5 K.

As the aging of the population aggravates, the problem of fall has aroused more attention. We have proposed a novel pre-impact fall detection algorithm and protection system. The real-time algorithm used the thresholds of vertical velocity and displacement profile to detect fall events in switching periods of fast motion. It can effectively solve the problem of false alarms of jump and jogging for daily-life applications. A second-order lag filtering algorithm method was utilized to reduce the drift of the vertical velocity with good performance. In addition, the vertical displacement profile was calculated by using the vertical velocity estimation. The algorithm got 93.6% sensitivity and 95.6% specificity, which was higher than the algorithm without displacement with 75.6% specificity. The results demonstrated the effectiveness of the proposed detection method, which were evaluated by subjects wearing fall detection and airbag system.

Adipokinetic hormone receptor (AKHR) was regarded as the crucial regulator of lipid consuming, but now has been renewed as a pluripotent neuropeptide G protein-coupled receptor. It has been identified in all sequenced bee genomes from the solitary to the eusocial. In the current study, we try to clarify the transitions of AKHR on lipid utilization and other potential functions from solitary to eusocial bees. The results showed that the AKHRs were divided into different groups based on their social complexity approximately. Nevertheless, the critical motifs and tertiary structures were highly conserved. As to the post-translational modifications, the eusocial possessed more phosphorylation residues and modification patterns, which might be due to the necessity of more diverse functions. These results suggest that AKHRs are highly conserved on both primary motifs and tertiary structures, but more flexible on posttranslational modifications so as to accommodate to more complicated eusocial life.

This paper concerns the characteristics analysis and design of a novel ironless linear synchronous motor (ILSM) with a novel double-side Halbach permanent magnet array. The analytical model of the linear motor for predicting the magnetic field in the air-gap at no-load is introduced. The magnetic flux density distribution of the double-side Halbach magnet array is solved analytically by using the equivalent magnetization intensity (EMI) method and its accuracy isvalidated by using the results obtained from the finite-element method. Expressions of the no-load back-EMF and the electromagnetic thrust of the ILSM are obtained. The design method of thecoils and permanent magnets are studied, respectively. The effects of the parameters of the magnets on the electrical properties of the ILSM are analyzed. A prototype motor is manufactured, and some experiments werecarried out with it.

The peptidoglycan recognition protein SAs (PGRP-SAs) from Bombus ignitus (Bi-PGRP-SA), Apis mellifera (Am-PGRP-SA), and Megachile rotundata PGRP-SA (Mr-PGRP-SA) exhibit an intrinsic ability to preferentially bind to Dap-type peptidoglycan (PGN) from Bacillus subtilis rather than Lys-type PGN from Micrococcus luteus. This ability is more analogous to the binding exhibited by PGRP-LCx and PGRP-SD than to that exhibited by PGRP-SA in Drosophila. Moreover, Bi-PGRP-SA and Am-PGRP-SA share greater sequence identity with Drosophila PGRP-LCx than with PGRP-SD and retain several conserved contact residues, including His37/His38, His60/His61, Trp66/Trp67, Ala150/Ala151, and Thr151/Thr152. However, the corresponding contact residue Arg85 is not a major anchor residue in bees (e.g., bumblebees, honeybees, and leaf-cutting bees), and an in silico analysis indicated that the residues Thr151/Thr152 and Ser153/Ser154 of Bi-PGRP-SA and Am-PGRP-SA are deduced to be anchor residues. In addition, the nonconserved residues Asp67 in Bi-PGRP-SA and Mr-PGRP-SA and His68 in Am-PGRP-SA are deduced to be involved in the binding to Dap-type PGNs in bumblebees, honeybees, and leaf-cutting bees. We conclude that the structures and specificities of PGRP-SAs in bees are more analogous to those of PGRP-LCx than to those of Drosophila PGRP-SA. This phenomenon might be explained by the fact that the evolutionary clade of Hymenoptera is more ancient than that of Diptera.

Superconducting nanowire single photon detectors (SNSPDs) have advanced various frontier scientific and technological fields such as quantum key distribution and deep space communications. However, limited by available cooling technology, all past experimental demonstrations have had ground-based applications. In this work we demonstrate a SNSPD system using a hybrid cryocooler compatible with space applications. With a minimum operational temperature of 2.8 K, this SNSPD system presents a maximum system detection efficiency of over 50% and a timing jitter of 48 ps, which paves the way for various space applications., Comment: 7 pages, 3 figures, 1 table, submitted to OE

Plant invasions are a major component of global change, but they may be affected by other global change components. Here we used a mesocosm-pot experiment to test whether high water availability, nitrogen (N) enrichment and their interaction promote performance of three invasive alien plants (Lepidium virginicum, Lolium perenne and Medicago sativa) when competing with a native Chinese grassland species (Agropyron cristatum). Single plants of the three invasive and the one native species were grown in the center of pots with a matrix of the native A. cristatum under low, intermediate or high water availability and low or high N availability. The invasive species L. virginicum and M. sativa grew larger, and produced a higher biomass relative to competitors than the native species A. cristatum did. Increasing water availability promoted biomass production of all species, but water availability did not change the biomass of the central plants relative to that of the competitors. Nitrogen addition also increased biomass production of all species, and it increased the biomass of the central plants more so than that of the competitors. The positive effect of N addition on the biomass of the central plants relative to that of the competitors increased with increasing water availability. However, compared to central plants of the native species, the positive effect of N addition on the relative biomass of L. virginicum decreased when water availability increased. These interactions indicate that future changes in water availability and N enrichment may affect the invasion success of different alien species differently. published

This paper proposes a method of position control based on BP-PID controller to implement the electrode position control of calcium carbide furnace. Firstly, the characteristics of the arc of the burner-electrode are studied and the arc current under the maximum heating power is deduced theoretically. Secondly, the position control strategy of the electrode is determined. Finally, the BP-PID controller is implemented by using the S-function in Matlab and simulated in Matlab/Simulink. The simulation results show that this method can control the position of the burner-electrode of calcium carbide furnace.

Invasive alien plant species threaten native biodiversity, disrupt ecosystem functions and can cause large economic damage. Plant invasions have been predicted to further increase under ongoing global environmental change. Numerous case studies have compared the performance of invasive and native plant species in response to global environmental change components (i.e. changes in mean levels of precipitation, temperature, atmospheric CO2 concentration or nitrogen deposition). Individually, these studies usually involve low numbers of species and therefore the results cannot be generalized. Therefore, we performed a phylogenetically controlled meta-analysis to assess whether there is a general pattern of differences in invasive and native plant performance under each component of global environmental change. We compiled a database of studies that reported performance measures for 74 invasive alien plant species and 117 native plant species in response to one of the above-mentioned global environmental change components. We found that elevated temperature and CO2 enrichment increased the performance of invasive alien plants more strongly than was the case for native plants. Invasive alien plants tended to also have a slightly stronger positive response to increased N deposition and increased precipitation than native plants, but these differences were not significant (N deposition: P = 0.051; increased precipitation: P = 0.679). Invasive alien plants tended to have a slightly stronger negative response to decreased precipitation than native plants, although this difference was also not significant (P = 0.060). So while drought could potentially reduce plant invasion, increases in the four other components of global environmental change considered, particularly global warming and atmospheric CO2 enrichment, may further increase the spread of invasive plants in the future.

1. Global environmental change not only includes changes in mean environmental conditions but also in temporal environmental fluctuations. Because it is frequently suggested that common species, and particularly invasive alien species, are phenotypically highly plastic, they might benefit more from these fluctuations than rare native and rare alien species. Experimental tests, however, are still lacking.2. Here, we tested whether alien plant species take more advantage of increases in resource levels and fluctuations therein than native species, and whether common species do so more than rare species. Therefore, we grew seven common alien, seven rare alien, nine common native and six rare native herbaceous plants, in one treatment with constantly low nutrient availability and five treatments with high nutrient availability that differed in temporal availability of nutrients (constant, increasing, decreasing, single large pulse, multiple smaller pulses).3. We found that all species produced more biomass and longer roots, and had a lower root mass fraction under high nutrient conditions than under low nutrient conditions, irrespective of their origin and commonness. Among the high nutrient treatments, the temporal pattern of nutrient supply also influenced biomass production, root allocation and root thickness, but the magnitude and/or directions of these responses varied among the groups of species. Particularly, we found that alien plant species, irrespective of whether they are common or rare, produced more biomass, and had a higher root mass fraction when nutrients were supplied as a single pulse in the middle of the growth period instead of supplied at a constant rate, whereas the reverse was true for the native species.4. Synthesis. Our study suggests that species origin does not drive differences in plant biomass production, root morphology and allocation in response to changes in mean environmental nutrient availability. However in our study, alien plant species, in contrast to native plant species, benefited from a large nutrient pulse. This suggests that increased fluctuations in nutrient availability might promote alien plant invasions. published

Global environmental changes can create novel habitats, promoting the growth of alien plants that often exhibit broad environmental tolerance and high phenotypic plasticity. However, the mechanisms underlying these growth promotory effects are unknown at present. Here, we conducted a phylogenetically controlled meta-analysis using data from 111 published studies encompassing the responses of 129 alien plants to global warming, increased precipitation, N deposition, and CO2 enrichment. We compared the differences in the responses of alien plants to the four global environmental change factors across six categories of functional traits between woody and non-woody life forms as well as C3 and C4 photosynthetic pathways. Our results showed that all four global change factors promote alien plant growth. Warming had a more positive effect on C4 than C3 plants. Although the effects of the four factors on the functional traits of alien plants were variable, plant growth was mainly promoted via an increase in growth rate and size. Our data suggest that potential future global environmental changes could further facilitate alien plant growth. published

The geographical distribution of species generally reflects their ability to colonise large habitats. Thus, research on species traits affecting the ability of species to colonise (i.e. arrive and establish) new territories is required. Our study investigates whether mycorrhizas and long-distance dispersal (LDD) syndromes play an important role in plant species distribution within mainland Germany, and whether they interact to drive plant distribution at a large scale. Using a dataset of 1070 vascular plant species containing information on LDD syndromes, mycorrhizal status, and distribution, we fitted phylogenetic generalised least squares regression models to assess the effects of LDD syndromes and mycorrhizas on plant distribution across Germany. Our study showed that species with LDD syndromes tended to be more widely distributed overall than species without any specialised dispersal structures relevant for LDD (i.e. ‘unspecialised’ species). In particular, plants with nutritive tissues, which attract frugivores that disperse seeds internally, were more widely distributed than ‘unspecialised’ species. Moreover, species associated with mycorrhizal fungi, particularly the facultative mycorrhizal species, were more widely distributed than non-mycorrhizal plants. Interestingly, mycorrhizal species with LDD syndromes tended to be more widely distributed than species without any specialised dispersal structures relevant for LDD, whereas the reverse was true for non-mycorrhizal species. Our study suggests that both LDD syndromes and mycorrhizas play an important role in plant distribution within the mainland. More importantly, we show the first evidence that mycorrhizas may interact with LDD syndromes to expand the geographic distribution of plant species within the mainland.

PGRP-LC is a significant pattern recognition receptor of the insect innate immune system that can recognize peptidoglycans and activate immune signaling pathways regulating the expression and release of antimicrobial peptides against infection. We for the first time analyzed the phylogenetic tree, purification and structure of bumblebee PGRP-LC. The results showed high conservation of bumblebee PGRP-LC among the 16 bumblebee species, and further phylogenetic analysis showed that the PGRP-LC phylogeny of different subgenera ( Subterraneobombus , Megabombus , Melanobombus , Bombus ) is consistent with that of the COI gene. Additionally, the phylogeny of PGRP-LCs among Bombus , Apis and the solitary bee Megachile rotundata coincides with the sociality evolution of bees. Moreover, bumblebee PGRP-LC (Bl-PGRP-LC) shares the Drosophila PGRP-LCx and PGRP-LCa topology, retaining conserved disulfide bonds and 80% binding residues involved in the interaction between TCT and PGRP-LCx. Therefore, Bl-PGRP-LC might share some similar binding characteristics with Drosophila PGRP-LCx. In addition, Bl-PGRP-LC has shorter β5 and β1 sheets, longer β2, β3, and β4 sheets and a shallow binding groove. To determine the characteristics of Bl-PGRP-LC, high-purity PGRP-LC inclusion bodies, soluble GST-tag Bl-PGRP-LC fusion protein and soluble pure Bl-PGRP-LC were obtained in vitro. The results will be helpful for further study of the function and structure of Bl-PGRP-LC.

Background and Aims It is frequently assumed that phenotypic plasticity can be very advantageous for plants, because it may increase environmental tolerance (fitness homeostasis). This should, however, only hold for plastic responses that are adaptive, i.e. increase fitness. Numerous studies have shown shade-induced increases in specific leaf area (SLA), and there is wide consensus that this plastic response optimizes light capture and thus has to be adaptive. However, it has rarely been tested whether this is really the case. Methods In order to identify whether SLA plasticity does contribute to the maintenance of high biomass of plant species under shaded conditions, a meta-analytical approach was employed. The data set included 280 species and 467 individual studies from 32 publications and two unpublished experiments. Key Results Plants increased their SLA by 55·4 % on average when shaded, while they decreased their biomass by 59·9 %. Species with a high SLA under high-light control conditions showed a significantly greater ability to maintain biomass production under shade overall. However, in contrast to the expectation of a positive relationship between SLA plasticity and maintenance of plant biomass, the results indicated that species with greater SLA plasticity were less able to maintain biomass under shade. Conclusions Although a high SLA per se contributes to biomass homeostasis, there was no evidence that plasticity in SLA contributes to this. Therefore, it is argued that some of the plastic changes that are frequently thought to be adaptive might simply reflect passive responses to the environment, or result as by-products of adaptive plastic responses in other traits.

The contact behavior with high-friction and low normal adhesion between a wafer and an end-effector of a wafer transfer robot is crucial to the high efficiency of wafer transfer. In this paper, a novel method of wafer transfer based on micro-fiber array is presented as well as the detailed design of micro-fiber array with high-friction and low-adhesion for wafer transfer. An interaction model is firstly established to obtain the friction and adhesion between micro-fiber array and wafer. Then, four typical failure modes of micro-fiber array are analyzed and a set of structure constraint conditions are established for the design of micro-fiber array with the feature of high-friction and low-adhesion for wafer transfer. A prototype based on SU-8 is prepared, and the experiments results show the prototype is with high friction and low normal adhesion, and capable of improving the efficiency of wafer transfer, which identify the feasibility of this method.

Real-time detection of contact states, such as stick-slip interaction between a robot and an object on its end effector, is crucial for the robot to grasp and manipulate the object steadily. This paper presents a novel tactile sensor based on electromagnetic induction and its application on stick-slip interaction. An equivalent cantilever-beam model of the tactile sensor was built and capable of constructing the relationship between the sensor output and the friction applied on the sensor. With the tactile sensor, a new method to detect stick-slip interaction on the contact surface between the object and the sensor is proposed based on the characteristics of friction change. Furthermore, a prototype was developed for a typical application, stable wafer transferring on a wafer transfer robot, by considering the spatial magnetic field distribution and the sensor size according to the requirements of wafer transfer. The experimental results validate the sensing mechanism of the tactile sensor and verify its feasibility of detecting stick-slip on the contact surface between the wafer and the sensor. The sensing mechanism also provides a new approach to detect the contact state on the soft-rigid surface in other robot-environment interaction systems.

In this paper, a novel ironless linear synchronous motor with a cooling system is proposed. Firstly, the topology of this ironless linear synchronous motor with a cooling system is introduced. Flux density in the cooling system is obtained analytically by the separation of variables method according to the boundary conditions. The eddy current braking force induced by the cooling system is calculated and validated by finite element method. Then, the influence of the motor parameters on the eddy current braking force is investigated. At last, a prototype is manufactured and some experiments are carried out with the prototype. The experiment results are validated by finite element analyzed results.