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Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei. As a future high energy nuclear physics project, an Electron-ion collider in China (EicC) has been proposed. It will be constructed based on an upgraded heavy-ion accelerator, High Intensity heavy-ion Accelerator Facility (HIAF) which is currently under construction, together with a new electron ring. The proposed collider will provide highly polarized electrons (with a polarization of $\sim$80%) and protons (with a polarization of $\sim$70%) with variable center of mass energies from 15 to 20 GeV and the luminosity of (2-3) $\times$ 10$^{33}$ cm$^{-2}$ s$^{-1}$. Polarized deuterons and Helium-3, as well as unpolarized ion beams from Carbon to Uranium, will be also available at the EicC. The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region, including 3D tomography of nucleon; the partonic structure of nuclei and the parton interaction with the nuclear environment; the exotic states, especially those with heavy flavor quark contents. In addition, issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC. In order to achieve the above-mentioned physics goals, a hermetical detector system will be constructed with cutting-edge technologies. This document is the result of collective contributions and valuable inputs from experts across the globe. The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States. The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China., EicC white paper, written by the whole EicC working group

The International Thermonuclear Experimental Reactor (ITER) is one of the largest international cooperative projects with many participants from different research groups in institutes and universi...

Active and durable anode electrocatalysts are of vital importance for practical implementation of fuel cells. However, the surface-adsorbed reaction intermediates, especially CO, easily poison and ...

The regenerative repair of large bone defects is a major problem in orthopedics and clinical medicine. The key problem is the lack of ability of existing bone graft materials to promote osteogenesis and angiogenesis. Previous studies have shown that the osteogenic or angiogenic abilities of these materials could be significantly improved by adding miRNA or small-molecule drugs to bone graft materials; however, the synergistic effect arising from this combination is not clear. Therefore, we proposed to construct a dual drug delivery system that could simultaneously achieve the co-encapsulation and co-delivery of miRNA and small-molecule drugs to explore the effect of a dual drug delivery system on bone repair. In this study, we constructed dual-sized pore structure calcium-silicon nanospheres (DPNPs) and achieved the co-encapsulation of miR-210, angiogenic gene drugs, and simvastatin (Siv), a small-molecule osteogenic drug, through metal-ion coordination and physical adsorption. In vitro and in vivo osteogenic and angiogenic experiments showed that the dual drug delivery system (Siv/DPNP/miR-210) exhibited better properties than those of the individual unloaded and single drug-loaded systems and could significantly accelerate the process of bone repair, which provides a novel strategy for the regeneration and repair of bone defects.

Multiple hydropower reservoirs operation is an effective measure to rationally allocate the limited water resources under uncertainty. With the rapid expansion of water resources system, it becomes much more difficult for traditional methods to quickly yield the reasonable operational policy. Grey wolf optimizer, inspired by the wolves’ hunting behaviors, is a famous metaheuristic method to resolve engineering optimization problems, but still suffers from the local convergence and search stagnation defects. To alleviate this problem, this study proposes a hybrid grey wolf optimizer (HGWO) where the hyperbolic accelerating strategy is introduced to improve the local search ability; the adaptive mutation strategy is used to diversify the swarm; the elitism selection strategy is used to enhance the convergence speed. The experimental results show that the HGWO method can produce better solutions than its original version in several test functions. Then, the HGWO method is applied to resolve the optimal operation of a real-world hydropower system with the goal of maximizing the total generation benefit. The simulations indicate that the HGWO method produces satisfying scheduling schemes than several control methods in terms of all the statistical indicators. Hence, with the merits of superior search ability, rapid convergence rate and gradient information avoidance, HGWO proves to be a promising alternative optimization tool for the complex multireservoir system operation problem.

Active non-noble metal catalysts plays a decisive role for water electrolysis, however, the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging task. Herein, a facile one-step electrodeposition route in deep eutectic solvents (DESs) is developed for morphology-controllable synthesis of cobalt oxide/phosphate-carbon nanohybrids on nickel foam (CoPO@C/NF). A series of CoPO@C/NF nanostructures including cubes, octahedrons, microspheres and nanoflowers are synthesized, which show promising electrocatalytic properties toward oxygen and hydrogen evolution reactions (OER/HER). Such surface self-organized microstructure with accessible active sites make a significant contribution to the enhanced electrochemical activity, and hybridizing cobalt oxide with cobalt pyrophosphates and carbon can result in enhanced OER performance through synergistic catalysis. Among all nanostructures, the obtained microspherical CoPO@C/NF-3 catalyst exhibits excellent catalytic activities for OER and HER in 1.0 M KOH, affording an anodic current density of 10 mA cm−2 at overpotentials of 293 mV for OER and 93 mV for HER, with good long-time stability. This work offers a practical route for engineering the high-performance electrocatalysts towards efficient energy conversion and storage devices.

Two new species, Tetradinodula gaoligongensis Li et Mao, sp. nov. and T. reticulata Mao et Li, sp. nov., are described and photographed from China. The differential diagnosis of all known species o...

Lipopolysaccharide (LPS) is a component of the outer membrane of Gram-negative bacteria. Recently, a label-free immobilized antimicrobial peptide (AMP) surface plasmon resonance platform was developed to successfully distinguish LPS from multiple bacterial strains. Among the tested AMPs, SMAP29 exhibited excellent affinity with LPS and has two independent LPS-binding sites located at two termini of the peptide. In this study, sum frequency generation vibrational spectroscopy was applied to investigate molecular interactions between three LPS samples and surface-immobilized SMAP29 via the N-terminus, the C-terminus, and a middle site at the solid/liquid interface in situ in real-time, supplemented by circular dichroism spectroscopy. It was found that the conformations and orientations of surface-immobilized SMAP29 via different sites are different when interacting with the same LPS, with different interaction kinetics. The same SMAP29 sample also has different structures and interaction kinetics while interacting with different LPS samples with different charge densities and hydrophobicities. The observed results on molecular interactions between surface-immobilized peptides and LPS can well interpret the different adsorption amounts of various LPSs on different surface-immobilized peptides.

In this paper, by changing the Si/Al ratio of the catalyst, the reaction temperature and the weight hourly space velocity, the optimal reaction conditions for the preparation of isoprene in one-step condensation of isobutene and formaldehyde on HZSM-5 molecular sieve catalyst was investigated. The catalysts were characterized by N2 adsorption–desorption, X-ray diffraction (XRD), NH3-temperature programmed desorption (NH3-TPD), thermogravimetric-differential scanning calorimetry (TG-DSC) analysis and Fourier transform infrared spectra of the adsorbed pyridine (Py-IR). The catalytic performance of this reaction was studied and the possible reaction network diagram was proposed. It is concluded that the active sites of gas phase condensation between formaldehyde and isobutene were medium strong Lewis acid sites. Meanwhile the strong acid sites would cause side reactions and carbon deposition. It is speculated that the active sites of the reaction of formaldehyde and isobutene are Lewis acid sites on the HZSM-5 catalyst. The mechanism is presumed to activate the formaldehyde molecule at the Lewis acid sites, and then the formaldehyde molecule is condensed with isobutene to form isoprene.

Significance Carotenoids are essential molecules in oxygenic photoautotrophs, and they fulfill essential requirements for human and animal nutrition. How carotenoid accumulation is regulated in the chloroplast, a cyanobacterium-derived organelle, remains poorly understood, despite significant advancements in identifying enzymes of the carotenoid biosynthetic pathway. This study identifies a role of chloroplast Sec14-like 1 (CPSFL1), a CRAL-TRIO protein of eukaryotic origin, in modulation of carotenoid biosynthesis and accumulation in the chloroplast. The CPSFL1 protein represents an isoprenoid- and carotenoid-binding protein that associates with membranes through interactions with the phospholipid phosphatidic acid. These findings have implications for understanding carotenoid biosynthesis and optimizing algal carotenoid nutritional quality., Plastid isoprenoid-derived carotenoids serve essential roles in chloroplast development and photosynthesis. Although nearly all enzymes that participate in the biosynthesis of carotenoids in plants have been identified, the complement of auxiliary proteins that regulate synthesis, transport, sequestration, and degradation of these molecules and their isoprenoid precursors have not been fully described. To identify such proteins that are necessary for the optimal functioning of oxygenic photosynthesis, we screened a large collection of nonphotosynthetic (acetate-requiring) DNA insertional mutants of Chlamydomonas reinhardtii and isolated cpsfl1. The cpsfl1 mutant is extremely light-sensitive and susceptible to photoinhibition and photobleaching. The CPSFL1 gene encodes a CRAL-TRIO hydrophobic ligand-binding (Sec14) domain protein. Proteins containing this domain are limited to eukaryotes, but some may have been retargeted to function in organelles of endosymbiotic origin. The cpsfl1 mutant showed decreased accumulation of plastidial isoprenoid-derived pigments, especially carotenoids, and whole-cell focused ion-beam scanning-electron microscopy revealed a deficiency of carotenoid-rich chloroplast structures (e.g., eyespot and plastoglobules). The low carotenoid content resulted from impaired biosynthesis at a step prior to phytoene, the committed precursor to carotenoids. The CPSFL1 protein bound phytoene and β-carotene when expressed in Escherichia coli and phosphatidic acid in vitro. We suggest that CPSFL1 is involved in the regulation of phytoene synthesis and carotenoid transport and thereby modulates carotenoid accumulation in the chloroplast.

A high-resolution electromagnetic study has helped to define the mineralization and alteration system of the Cretaceous volcano-sedimentary hosted epithermal gold (Au) deposit in Tuoniuhe, northeast China. Audio-magnetotelluric (AMT) array data were acquired to map the regional resistivity structure of the Mesozoic volcanic field, whereas an AMT profile and a ground magnetic survey line with denser site spacing were deployed across the deposit to image the alteration and mineralization system. The electrical resistivity model from 2D inversion of the AMT profile data reveals a low-resistivity (approximately [Formula: see text]) cover from the surface to a depth of 0.1 km, which is likely caused by clay and sulfide minerals in the subaerial alteration zone. The magnetic survey and a geologic borehole log assisted in outlining a zone of tonalite and andesite with silicification in the depth interval of 0.1–0.3 km, featuring high resistivity ([Formula: see text]) and high magnetization ([Formula: see text]). This zone is a potential gold target bounded by two channels of moderate resistivity (approximately [Formula: see text]) to its northwest and southeast. The two channels possibly coincide with breccia pipes with fractured stockworks and high permeability to allow gold-bearing fluids to move toward the surface. The 2D and 3D resistivity models reveal regions of low resistivity ([Formula: see text]) at the depth range of 0.5–1.0 km beneath the Cretaceous calderas and the deposit, which might be related to magmatic cryptoexplosion breccia. In the 2D resistivity model, this magmatic cryptoexplosion breccia zone connects to the subaerial alteration zone through the two breccia pipes, indicative of a circulation system of gold-bearing fluids. Given the coincidence of Cretaceous volcanism and the age of mineralization, the Cretaceous magma is inferred to have supplied heat that drove the convective hydrothermal activity and also was a source of magmatic fluids that led to the development of the Tuoniuhe epithermal gold deposit.

Using character of mutually orthogonal Latin squares, we first prove that two special squares are orthogonal to a complete set of mutually orthogonal Latin squares of order d. Then using the complete set of mutually orthogonal Latin squares of order d and two special squares, we construct d + 1 mutually unbiased bases in $\mathbb {C}^{d} \otimes \mathbb {C}^{d}$, which include d − 1 mutually unbiased maximally entangled bases and two mutually unbiased product bases. We also present the corresponding construction in $\mathbb {C}^{3} \otimes \mathbb {C}^{3}$, $\mathbb {C}^{4} \otimes \mathbb {C}^{4}$ and $\mathbb {C}^{5} \otimes \mathbb {C}^{5}$.

Identification of geochemical anomalies from geological background is of great significance in the exploration of complex mineralization systems. For a 2D problem, the window-based local singularity mapping has been used widely to identify the distribution patterns of geochemical data. However, the optimal window parameters for calculating the singularity index are hard to determine. Previous studies commonly use the default parameters when applying singularity mapping. In this study, window-based local singularity mapping was performed and improved by comprehensive analysis of multiple parameters to explore geochemical anomalies associated with gold mineralization in the Xishan deposit, North China, with the aim of revealing undiscovered mineralization. By using Au anomalies as an example, the parameters that may influence the result of window-based local singularity processing have been analyzed and discussed to improve the mapping result. The parameters include the average concentration calculation algorithm, the shape of the sliding windows, the window size increment and the number of windows. Success-rate curves and area under the success-rate curve have been used to assess the spatial correlation of the singularity map with the known mineral occurrences. While square sliding window is the most regularly used window shape, circular and elliptical windows can be alternative choices. We found that the directions of major axis of the ellipses parallel or quasi-parallel to geological strike fit the locations of ore deposits better if the mineralization system is controlled by regional faults. After taking the influence of different parameters into account, geochemical anomalies were successfully separated from background and have been enhanced compared to anomalies identified solely from concentration values. Singularity–quantile analysis has been applied to recognize and separate multiple geochemical anomaly populations based on the singularity map in frequency and spatial domain. While the Au concentration map shows quite scattered strong and weak geochemical anomalies, the linear regions of positive singularity resolved by singularity–quantile analysis coincide well with the location of regional faults and alteration zones, which might indicate footprints of ore-forming fluids. Based on the singularity maps of multi-elements (Au, Ag, Cu and Pb), we resolved two prospect areas of mineralization bounded by regional faults, hydrothermally altered rocks and lamprophyres with positive singularity, which warrant further investigation for undiscovered mineralization.

Research into urban expansion patterns and their driving forces is of great significance for urban agglomeration development planning and decision-making. In this paper, we reveal the multi-dimensional characteristics of urban expansion patterns, based on the intensity index of the urban expansion, the differentiation index of the urban expansion, the fractal dimension index, the land urbanization rate, and the center of gravity model, by taking the Beijing-Tianjin-Hebei (Jing-Jin-Ji) urban agglomeration as an example. We then build the center of gravity-geographically and temporally weighted regression (GTWR) model by coupling the center of gravity model with the GTWR model. Through the analysis of the temporal and spatial patterns and by using the center of gravity-GTWR model, we analyze the driving forces of the urban land expansion and summarize the dominant development modes and core driving forces of the Jing-Jin-Ji urban agglomeration. The results show that: 1) Between 1990 and 2015, the expansion intensity of the Jing-Jin-Ji urban agglomeration showed a down-up-down trend, and the peak period was in 2005–2010. Before 2005, high-speed development took place in Beijing, Tianjin, Baoding, and Langfang; after 2005, rapid development was seen in Xingtai and Handan. 2) Although the barycenter of cities in the Jing-Jin-Ji urban agglomeration has shown a divergent trend, the local interaction between cities has been enhanced, and the driving forces of urban land expansion have shown a characteristic of spatial spillover. 3) The spatial development mode of the Jing-Jin-Ji urban agglomeration has changed from a dual-core development mode to a multi-core development mode, which is made up of three functional cores: the transportation core in the northern part, the economic development core in the central part, and the investment core in the southern part. The synergistic development between each functional core has led to the multi-core development mode. 4) The center of gravity-GTWR model combines the analysis of spatial and temporal nonstationarity with urban spatial interaction, and analyzes the urban land expansion as a space-time dynamic system. The results of this study show that the model is a feasible approach in the analysis of the driving forces of urban land expansion.

Accurate mass data of transuranium nuclei is particularly important for the study of superheavy nuclei and the investigation of “island of stability”. A low energy mass spectrometer to provide high-precision mass measurement and isobaric separation of short-lived fusion-evaporation reaction products is planned at the Spectrometer for Heavy Atom and Nuclear Structure (SHANS). A multi-reflection time-of-flight mass analyzer for SHANS has been designed and constructed and is being tested now. In the in-trap-lift mode, the latest simulation results by using SIMION give a maximal mass resolving power of 1.6 × 105 for a TOF of 6.4 ms, and the preliminary test results by applying the simulated voltages show that its mass resolving power has reached ≈ 7000 for a TOF of 1.6 ms.

The current artificial photocatalysts often suffer from photocorrosion-induced irreversible damage and low efficiency. Here we report that under the UV irradiation of aqueous isopropanol solution, which photolysis to produce acetone and consume photoelectron in time and be oxidized to form acetone. And then the platinum nanoparticles can coordinate with product acetone on their surfaces to create a unique photocatalysis system for high efficient hydrogen evolution. In this system, the inherent close bonding between photoactive surface complexes and metallic platinum sites creates an efficient donor-acceptor system for charge transfer and leads to high efficiency, with hydrogen generation rate of 8.01 mmol⋅ h−1. Furthermore, in the presence of isopropanol the photoactive acetonyl-platinum complexes are generated reproducibly via a continuous isopropanol-to-acetone conversion and thus work sustainably. This finding indicates the possibility of artificially creating self-reproducible systems to drive photocatalytic reactions efficiently and robustly.

Iron-based catalysts were one of the most effective catalysts in the oxidative dehydrogenation of n-butene, however, the roles of spinel and α-Fe2O3 in the biphasic catalyst have remained controversial. Herein, we found that biphasic catalyst exhibited much superior catalytic performance compared to each individual component. According to the temperature programmed desorption, XPS and kinetics studies results, it was speculated that ZnFe2O4 was primarily responsible for activating n-butene and α-Fe2O3 was used to activate O2. Moreover, the key factor for the catalytic activity of the biphasic catalyst were investigated and kinetic studies showed that reaction rates were well correlated with the apparent pre-exponential factor. Therefore, the efficient contact between ZnFe2O4 and α-Fe2O3 may lead to the improvement of the activity. In addition, the reaction mechanism over α-Fe2O3/ZnFe2O4 was proposed to be the interface reaction based on the catalytic evaluation results of substituting ZnFe2O4 by the redox-inactive ZnAl2O4.

The multinucleon transfer (MNT) reaction is one promising way to produce neutron-rich heavy nuclei and even super heavy nuclei and attracts more and more attentions theoretically and experimentally. A low energy nuclear structure spectrometer called LENSHIAF specific to the MNT reactions will be designed and constructed in the ongoing big project HIAF in China. In the LENSHIAF spectrometer, the most challenge part is how to collect and stop efficiently the high-energy MNT products into the gas cell. By using Monte-Carlo method, the geometry of the gas cell, the thickness of the titanium window/degrader, and the optimal gas pressure filled in the gas cell have been calculated and estimated. For neutron-rich nuclei around N = 126 from 136Xe + 198Pt reaction, with a titanium window/degrader with a thickness of 2.5–3.5 μ m, a cylindrical helium gas cell with a length of 0.6 m and a diameter of 1.2 m can satisfy the requirements to stop the target-like fragments. For heavier and super heavy nuclei from 238U + 238U reaction, with a 5–8 μ m thick titanium window/degrader, the cylindrical gas cell has to be as big as a length of at least 1.6 m and a diameter of 1.6 m.

The grand challenge in the development of atomically dispersed metallic catalysts is their low metal-atom loading density, uncontrollable localization and ambiguous interactions with supports, posing difficulty in maximizing their catalytic performance. Here, we achieve an interface catalyst consisting of atomic cobalt array covalently bound to distorted 1T MoS2 nanosheets (SA Co-D 1T MoS2). The phase of MoS2 transforming from 2H to D-1T, induced by strain from lattice mismatch and formation of Co-S covalent bond between Co and MoS2 during the assembly, is found to be essential to form the highly active single-atom array catalyst. SA Co-D 1T MoS2 achieves Pt-like activity toward HER and high long-term stability. Active-site blocking experiment together with density functional theory (DFT) calculations reveal that the superior catalytic behaviour is associated with an ensemble effect via the synergy of Co adatom and S of the D-1T MoS2 support by tuning hydrogen binding mode at the interface., While single-atom catalysis offers an efficient materials usage, the ambiguous interactions with supports poses a difficulty in understanding catalytic performances. Here, authors show an ensemble effect via synergy of Co adatoms and the S of MoS2 supports to boost hydrogen evolution activities.

Solar-induced Fluorescence (SIF) has an advantage over greenness-based Vegetation Indices in detecting drought. This advantage is the mechanistic coupling between SIF and Gross Primary Productivity (GPP). Under water stress, SIF tends to decrease with photosynthesis, due to an increase in non-photochemical quenching (NPQ), resulting in rapid and/or sustained reductions in the fluorescence quantum efficiency (phi F). Water stress also affects vegetation structure via highly dynamic changes in leaf angular distributions (LAD) or slower changes in leaf area index (LAI). Critically, these responses are entangled in space and time and their relative contribution to SIF, or to the coupling between SIF and GPP, is unclear. In this study, we quantify the relative effect of structural and photosynthetic dynamics on the diurnal and spatial variation of canopy SIF in a potato crop in response to a replicated paired-plot water stress experiment. We measured SIF using two platforms: a hydraulic lift and an Unmanned Aerial Vehicle (UAV) to capture temporal and spatial variation, respectively. LAD parameters were estimated from point clouds and photographic data and used to assess structural dynamics. Leaf phi F estimated from PAM fluorescence measurements were used to represent variations in photosynthetic regulation. We also measured foliar pigments, operating quantum yield of photosystem II (PSII), photosynthetic gas exchange, stomatal conductance and LAI. We used a radiative transfer model (SCOPE) to provide a means of decoupling structural and photosynthetic factors across the diurnal and spatial domains. The results demonstrate that diurnal variation in SIF is driven by photosynthetic and structural dynamics. The influence of phi F was prominent in the diurnal SIF response to water stress, with reduced fluorescence efficiencies in stressed plants. Structural factors dominated the spatial response of SIF to water stress over and above phi F. The results showed that the relationship between SIF and GPP is maintained in response to water stress where adjustments in NPQ and leaf angle co-operate to enhance the correlation between SIF and GPP. This study points to the complexity of interpreting and modelling the spatiotemporal connection between SIF and GPP which requires simultaneous knowledge of vegetation structural and photosynthetic dynamics.

Aims: Aboveground plant litter inputs are important sources of soil carbon (C). We aimed to establish how experimentally altered litter inputs affect soil C to 1-m depth across different ecosystems, and over different timeframes. Methods: We performed a meta-analysis of 237 studies across 248 sites worldwide to assess the influence of treatment magnitude, treatment duration, initial soil C content, and climate on the response of soil C to altered aboveground litter inputs. Results: Overall, soil C content was lower under litter removal, but higher under litter addition compared to controls. The effects of litter manipulation were apparent throughout the soil profile and were related to treatment magnitude. Soil C content declined markedly with increasing duration of litter removal, whereas the positive effect of litter addition attenuated over time. Cropland management practices (bare fallow or additional straw incorporation) had similar effects on soil C to litter removal and addition treatments. Conclusions: Our study reveals rapid and consistent changes in soil C content with altered litter inputs and provides important insights into plant residue management to enhance soil C sequestration. We highlight the need for long-term experiments, with a greater focus on the processes underpinning soil C storage in different ecosystems.

BP neural network can be said to be the most complete neural network among the existing neural networks. In recent years, with the improvement of people’s living standards, people have become more concerned about sports and the improvement of physical fitness. Many people have begun to go out of the room and go outdoors, seeking the joy of physical exercise in nature. The rapid development of sports has not only mobilized people’s desire to exercise but also promoted the common development of surrounding industries. As a professional sportswear, it must not only ensure comfort and beauty but also ensure certain functions. In running sports, most people wear tight-fitting clothing. This is because people believe that tight-fitting clothing can reduce the resistance of clothing fabrics to running and improve athletic performance. However, if the clothing is too tight, not only can it not achieve the purpose of improving athletic performance, but it will also compress the blood vessels and affect the health of the human body. The purpose of this article is to study the related mechanism of running exercise to produce fatigue feeling and to provide a set of normative evaluation criteria for running exercise. In the process of development, we should pay attention to sustainable development, and the development of ecologically fragile areas is facing serious problems such as soil erosion. During the investigation, we discovered that the topography, climate, rock conditions, and other natural factors in a certain county make the ecological environment of this area more fragile than other areas. In such a fragile ecological environment, there are fewer types of organisms. The stability is also poor; coupled with the human over-exploitation of resources and other impacts, the soil erosion in the area is serious, and natural disasters occur frequently.

The surface mass balance scheme dEBM (diurnal Energy Balance Model) provides a novel interface between the atmosphere and land ice for Earth System modeling, which is based on the energy balance of glaciated surfaces. In contrast to empirical schemes, dEBM accounts for changes in the Earth's orbit and atmospheric composition. The scheme only requires monthly atmospheric forcing (precipitation, temperature, shortwave and longwave radiation, and cloud cover). It is also computationally inexpensive, which makes it particularly suitable to investigate the ice sheets' response to long-term climate change. After calibration and validation, we analyze the surface mass balance of the Greenland Ice Sheet (GrIS) based on climate simulations representing two warm climate states: a simulation of the Mid Holocene (approximately 6000 years before present) and a climate projection based on an extreme emission scenario which extends to the year 2100. The former period features an intensified summer insolation while the 21st century is characterized by reduced outgoing long wave radiation. Specifically, we investigate whether the temperature-melt relationship, as used in empirical temperature-index methods, remains stable under changing insolation and atmospheric composition. Our results indicate that the temperature-melt relation is sensitive to changes in insolation on orbital time scales but remains mostly invariant under the projected warming climate of the 21st century.

The impact of human activities on soil carbon (C) storage in tropical forests has aroused wide concern during the past decades, because these ecosystems play a key role in ameliorating global climate change. However, there remain uncertainties about how land-use history alters soil organic carbon (SOC) stability and storage in different forests. In this study, we measured the C content and mass distributions of soil aggregates, density fractions, mineral-bound C and microbial biomass C in the organic horizon, 0-10 cm and 10-20 cm soil layers in coniferous forest and evergreen broadleaf forest at Dinghushan Biosphere Reserve in tropical China. The broadleaf forest had larger SOC stocks than the coniferous forest, but the proportion of SOC stored in different density fractions at 0-10 cm soils was similar between forest types, while a greater proportion of SOC was stored in microaggregates in the coniferous forest. Most of the SOC was held as light fraction C in the organic horizon in the coniferous forest, whereas the concentrations of mineral-bound C were higher in the broadleaf forest. These findings indicate clear differences in the protection of SOC between broadleaf and coniferous forests growing on the same soil type. We propose that historic conversion of broadleaf forest to coniferous forest has reduced soil C sequestration capacity by altering the diversity and quality of plant inputs to the soil, which in turn affected macroaggregate formation, soil chemical properties and microbial biomass. Our results thus demonstrate that changes in forest tree species composition could have long-lasting effects on soil structure and carbon storage, providing crucial evidence for policy decisions on forest carbon sink management.

Verticillium wilt caused by Verticillium alfalfae results in severe production losses in alfalfa crops and is a Class A quarantined disease in China. During 2015 to 2017, 365 alfalfa fields from 21 locations in six provinces were surveyed, and 45 fields from three closely located sites in Gansu, China were found to have alfalfa plants with symptoms typical of Verticillium wilt, with disease incidence of 12.6 to 53.6%. Isolates were identified to species using morphological characteristics and a maximum likelihood phylogeny of the concatenated partial sequences of actin, elongation factor, glyceraldehyde-3-phosphate dehydrogenase, and tryptophan synthase gene regions of Verticillium isolates. Isolation incidence was 93.9% from roots, 71.7% from stems, 66.1% from petioles, and 32.2% from leaves of field-infected plants, indicative of systemic disease and sporadic distribution of this pathogen. In greenhouse tests, the pathogen infected seedlings and colonized vascular tissues when inoculated on seeds, on root tips, in soil, or in injured, but not uninjured, aerial tissues, causing systemic symptoms like those in the field and significant losses. Pathogenicity testing also revealed that five locally grown perennial legumes (stylo, milkvetch, sainfoin, white clover, and red clover) could host V. alfalfae, with a high virulence to milkvetch, sainfoin, and stylo. This study confirmed that V. alfalfae has become established in some regions of Gansu, China and that is a risk to the alfalfa industry in China.

Fine particulate matter (PM2.5) is of great concern to the public due to its significant risk to human health. Numerous methods have been developed to estimate spatial PM2.5 concentrations in unobserved locations due to the sparse number of fixed monitoring stations. Due to an increase in low-cost sensing for air pollution monitoring, crowdsourced monitoring of exposure control has been gradually introduced into cities. However, the optimal mapping method for conventional sparse fixed measurements may not be suitable for this new high-density monitoring approach. This study presents a crowdsourced sampling campaign and strategies of method selection for 100 m scale PM2.5 mapping in an intra-urban area of China. During this process, PM2.5 concentrations were measured by laser air quality monitors through a group of volunteers during two 5 h periods. Three extensively employed modelling methods (ordinary kriging, OK; land use regression, LUR; and regression kriging, RK) were adopted to evaluate the performance. An interesting finding is that PM2.5 concentrations in micro-environments varied in the intra-urban area. These local PM2.5 variations can be easily identified by crowdsourced sampling rather than national air quality monitoring stations. The selection of models for fine-scale PM2.5 concentration mapping should be adjusted according to the changing sampling and pollution circumstances. During this project, OK interpolation performs best in conditions with non-peak traffic situations during a lightly polluted period (holdout validation R2: 0.47–0.82), while the RK modelling can perform better during the heavily polluted period (0.32–0.68) and in conditions with peak traffic and relatively few sampling sites (fewer than ∼100) during the lightly polluted period (0.40–0.69). Additionally, the LUR model demonstrates limited ability in estimating PM2.5 concentrations on very fine spatial and temporal scales in this study (0.04–0.55), which challenges the traditional point about the good performance of the LUR model for air pollution mapping. This method selection strategy provides empirical evidence for the best method selection for PM2.5 mapping using crowdsourced monitoring, and this provides a promising way to reduce the exposure risks for individuals in their daily life.

Iron (Fe) is a vital microelement, and is beneficial for living organisms. Several studies have demonstrated that ample supplied of potassium (K) can alleviate Fe-deficiency-induced chlorosis in plants. In this work, the mechanism underlying K-mediated amelioration of Fe deficiency in Arabidopsis was investigated. Five-week-old Arabidopsis thaliana (Col-0) plants with similar sizes were grown either on complete nutrient solution (+Fe + K) or lacking of K (+Fe–K) or lacking of Fe (–Fe + K), or lacking both of Fe and K (–Fe–K) for 4 days:. The plants were then harvested, and their Fe content, soluble Fe content, phenolic compounds content, Fe translocation and uptake-related genes expression levels, polysaccharides concentration were analyzed, moreover, we also determined the pectin methylesterase activity and its methylation. Under Fe deficiency, K-deficient plants accumulated higher amounts of root apoplastic Fe along with a higher Fe content in pectin and hemicellulose 1, and which was rapidly decreased when K was included in the nutrition solution, indicating the operation of a cell wall Fe-remobilization mechanism. Under Fe-deficient condition, K supply significantly increased the secretion of phenolic compounds and the degree of pectin methylation, while decreased pectin and hemicellulose 1 contents as compared with –Fe–K, thereby promoting Fe reutilization from root cell walls. Furthermore, K supply also enhanced the reutilization of Fe from vacuoles through up-regulation of AtNRAMP3 expression. In addition, K supply stimulated several genes associated with long-distance transport of Fe expression, including AtFRD3, AtYSL2, and AtNAS1, suggesting ample K supply can enhance Fe transportation from roots to leaves. Stimulation of Fe reutilization from cell walls and vacuoles, as well as an enhancement of Fe transportation from roots to leaves were the major mechanism underlying K-mediated amelioration of Fe-deficiency in Arabidopsis plants.

The response of the eastern tropical Indian Ocean (ETIO) to heat fluxes of equal amplitude but opposite sign is investigated using the Community Earth System Model (CESM). A significant positive asymmetry in sea surface temperature (SST) is found over the ETIO—the warming responses to the positive forcing exceeds the cooling to the negative forcing. A mixed layer heat budget analysis is carried out to identify the mechanisms responsible for the SST asymmetry. Results show that it is mainly ascribed to the ocean dynamical processes, including vertical advections and diffusion. The net surface heat flux, on the contrary, works to reduce the asymmetry through its shortwave radiation and latent heat flux components. The former is due to the nonlinear relationship between SST and cloud, while the latter is resulted mainly from Newtonian damping and air-sea stability effects. Changes in the SST skewness are also evaluated, with more enhanced negative SST skewness over the ETIO found for the cooling than heating scenarios due to the asymmetric thermocline-SST feedback.

The beams with phase gradients along the line trajectory, i.e., with the momentum flux transverse to the optical axis were generated with the beam shaping method and applied for optical manipulations in this paper. The phase distributions of the reconstructed beam in the focal plane of the objective and the moving velocity of the trapped microparticles were experimentally investigated. The experimental results showed that the moving velocity of the trapped microparticles is linearly dependent on the phase gradient possessed by the reconstructed beam. Furthermore, a generated curve beam was used to transport microparticles quickly and automatically along the curved route to avoid an obstacle. The generation method of the beams with phase gradients is simple. The beams would have potential applications in the fields such as optical trapping and optical sorting.

We have evaluated the uncertainty analysis of the 3D electrical tomography inverse problem using model reduction via singular-value decomposition and performed sampling of the nonlinear equivalence region via an explorative member of the particle swarm optimization (PSO) family. The procedure begins with the local inversion of the observed data to find a good resistivity model located in the nonlinear equivalence region. Then, the dimensionality is reduced via the spectral decomposition of the 3D geophysical model. Finally, the exploration of the uncertainty space is performed via an exploratory version of PSO (RR-PSO). This sampling methodology does not prejudge where the initial model comes from as long as this model has a geologic meaning. The 3D subsurface conductivity distribution is arranged as a 2D matrix by ordering the conductivity values contained in a given earth section as a column array and stacking parallel sections as columns of the matrix. There are three basic modes of ordering: mode 1 and mode 2, by using vertical sections in two perpendicular directions, and mode 3, by using horizontal sections. The spectral decomposition is then performed using these three 2D modes. Using this approach, it is possible to sample the uncertainty space of the 3D electrical resistivity inverse problem very efficiently. This methodology is intrinsically parallelizable and could be run for different initial models simultaneously. We found the application to a synthetic data set that is well-known in the literature related to this subject, obtaining a set of surviving geophysical models located in the nonlinear equivalence region that can be used to approximate numerically the posterior distribution of the geophysical model parameters (frequentist approach). Based on these models, it is possible to perform the probabilistic segmentation of the inverse solution found, meanwhile answering geophysical questions with its corresponding uncertainty assessment. This methodology has a general character could be applied to any other 3D nonlinear inverse problems by implementing their corresponding forward model.

The Tm3+/Ho3+-SrLaGa3O7 crystal was grown using the Czochralski (CZ) method. The absorption spectra, the fluorescence spectra around 2.0 μm and energy-transfer (ET) schemes between Tm3+ ions and Ho3+ ions has been studied. The lasing performance of Tm3+/Ho3+-SrLaGa3O7 crystal for a-cut and c-cut pumped by a fiber-coupled laser diode laser are presented in this paper. The maximum output powers of 6.15 W for a-cut crystal at 2041 nm and 2.51 W for c-cut crystal at 2044 nm have been obtained, respectively. The maximum slope efficiency in terms of absorbed pump power nearly reached 36.5% for the a-cut crystal and about 18.8% for the c-cut crystal. In addition, the width of tuning can reach about 450 nm, suggesting the potential of these crystals for ultrashort pulse generation by mode-locking.

Highly porous (specific surface area, SBET, 1400 m2/g) and rich in surface groups activated carbons (ACs) were obtained from cotton stalks using either a direct or indirect activation. They were characterized by adsorption of nitrogen, thermal analysis combined with mass spectrometry, potentiometric titration, and X-ray photoelectron spectroscopy (XPS). XPS analysis indicated that the indirect activation led to more nitrogen on the surface incorporated as pyridinic and graphitic/quaternary species. These species were beneficial for a carbon application as oxygen reduction reaction (ORR) electrocatalysts and supercapacitors. The carbons were catalytically active in ORR with a number of electron transfer from 2.15 to 3.40 and onset potential of 0.810 V vs. reference hydrogen electrode (RHE). Their capacitance was around 180 F g−1 at 1 A g−1 when measured in an alkaline medium. The dependence of the performance on the porosity and nitrogen content was found, indicating suitability of cotton stalks obtained using the indirect activation as precursors of carbons of promising electrochemically active features.

Plant stoichiometry is critical for the structure and functions of ecosystems. Previous studies on large-scale patterns of plant stoichiometry have focused on single tissues; and the controlling factors have focused on climatic factors or plant functional groups. Here we present results based on an intensive field investigation across China’s forest ecosystems, to comprehensively assess the effect of climatic factors, plant functional groups, soil N and P stoichiometry on N and P stoichiometry of different tree tissues. The P concentrations in all tissues were significantly lower when mean annual temperature (MAT) and mean annual precipitation (MAP) were higher, and the N:P ratios in all tissues were significantly higher when MAT and MAP were higher. The N concentrations of branches and trunks were negatively related to MAT and MAP, however, the leaf N concentrations did not change with MAT and MAP. The root N also did not change with MAT, but decreased significantly with MAP. Soil total N had little influence on tree N, however, tree tissue P concentrations significantly increased when soil P increased. The N contents of all tissues were mainly affected by plant functional groups, however, climate factors and soil P content were the main predictors of P and N:P ratios of all tissues. Our results suggest that tree tissue N:P ratios were largely related to climatic factors, and were shaped by soil P rather than soil N in China’s forest ecosystems.

Third-generation epidermal growth factor receptor (EGFR)L858R/T790M inhibitors are still the main drugs for the treatment of advanced non-small cell lung cancer (NSCLC), and these drugs have achieved remarkable clinical efficacy. However, there are still many patients suffering from drug-resistant mutations and drug side effects caused by NSCLC. In this study, guided by the molecular simulation, we applied a structure-based drug design strategy (SBDD) and optimized the structure to obtain a series of potent and selective EGFRL858R/T790M inhibitors. The most potent compound 18e demonstrated excellent kinase inhibitory activity and selectivity for EGFRL858R/T790M double mutants and the IC50 value reached nanomolar level. The selectivity of 18e against wild-type EGFR was near to 200-fold. In addition, compound 18e also inhibited H1975 cells proliferation at G2/M phase and induced apoptosis at a concentration of 0.25 μM, which makes it more valuable for potential lung cancer research.

The detection of nitrofuran antibiotics and toxic inorganic anions is currently necessary and challenging because their abuse and/or residuals have caused severe environmental pollution and illness. A heterometallic two-dimensional (2D) layered complex, {[Eu2Na(Hpddb)(pddb)2(CH3COO)2]·2.5(DMA)}n (1), was solvothermally synthesized and structurally and photophysically characterized. Pairs of acetate aggregated {Eu2Na(CH3COO)2} chains are periodically interconnected by V-shaped 4,4'-(pyridine-2,6-diyl)dibenzolate (pddb) linkers. More interestingly, the layered complex exhibits a bright red emission and can efficiently discriminate nitrofuran antibiotics by luminescent quenching with a strong quenching constant (Ksv) and low detection limit (LOD) of 4.93 × 104 M-1 and 0.64 μM for nitrofurazone, 4.42 × 104 M-1 and 0.68 μM for nitrofurantoin as well as 2.13 × 104 M-1 and 1.06 μM for furazolidone. Additionally, 1 can also probe trace amounts of toxic Cr2O72- and MnO4- anions with Ksv = 6.45 × 103 M-1 and LOD = 5.35 μM for Cr2O72- and Ksv = 2.84 × 103 M-1 and LOD = 5.99 μM for MnO4- anions. These interesting results indicate that heteromatallic coordination polymers can serve as favorable dual- or even multiple-responsive luminescence sensors to selectively recognize different kinds of contaminants.

With ever-increasing demand for balancing CO2 emissions and maximizing electrical energy supplies, Li–CO2 electrochemistry, coupled with dual characteristics of advanced energy storage and effective CO2 fixation, has been attracting considerable attention from researchers. Herein, we offer a real-time, in-depth, and overall review of the latest research progress concerning CO2 reduction/evolution reaction mechanisms in Li–CO2/O2 and Li–CO2 electrochemical systems. Meanwhile, affecting factors on the reaction pathways and the identification of discharge products are summarized and discussed. Then, Li anode/electrolyte interface construction, electrolyte properties and selection of cathode materials/catalysts and design strategy, especially their effect on the performance of Li–CO2/O2 and Li–CO2 batteries, are explored and possible solutions and suggestions are provided. Building on an in-depth understanding of Li–CO2 electrochemistry, novel flexible Li–CO2 batteries and key factors are summarized. Furthermore, based on advanced research progress in the past several years, we identify the main problems, controversies, and challenges currently existing in various battery components that remain to be addressed to design more practicable Li–CO2/O2 and Li–CO2 batteries. Finally, future research directions and opportunities are presented.

A novel charge‐transfer complex triggered sulfonylation of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with mild reaction conditions has been developed. The formation of a charge‐transfer complex between electron‐withdrawing (hetero)aryl sulfonyl chloride and DABCO allows the synthesis of N‐ethylated piperazine sulfonamide in good yields. The reaction has a high functional group tolerance. Spectroscopic studies confirmed the charge‐transfer complex formation between sulfonyl chlorides and DABCO, which facilitates the C−N bond cleavage of DABCO.

If a sacrificial agent is selectively oxidized to generate high-value chemicals during photocatalytic hydrogen production, then photocatalytic water splitting is more meaningful in consideration of green chemistry. GONaOH was obtained after hydrothermal treatment of graphene oxide (GO) using 10 mol L−1 NaOH. The average hydrogen production rate could reach 7.36 mmol h−1 over 0.50 g L−1 GONaOH photocatalyst for a reaction of 12 h. And the sacrificial agent isopropanol could undergo selective oxidative C–C coupling to generate pinacol. The isopropanol conversion rate was 77.95%, and the pinacol selectivity was 62.32%. Also, the GONaOH photocatalytic selective oxidative C–C coupling mechanism of isopropanol was further studied. The ˙OH concentration on the photocatalyst surface was verified as a key factor influencing pinacol selectivity. Under the effect of GONaOH photocatalyst, ˙OH radicals were used for the oxidative dehydrogenation of isopropanol to generate 2-hydroxyisopropyl radicals, and pinacol was generated through C–C coupling. Meanwhile, acetone byproducts could further undergo hydrogenation–dehydrogenation coupling reaction with isopropanol to finally generate pinacol.

Stimulus-driven color-change films are a basic optical component for the fabrication of a stimulus-driven color-change optical device. The practical application of this device is greatly affected by the performance of the stimulus-driven color-change film. Herein, we present the W18O49 honeycomb mesoporous pattern (HMP) film with excellent electrochromic performance. The W18O49 HMP film is prepared on a flexible substrate (indium tin oxide-coated polyethylene terephthalate polyester film, ITO-PET) by integrating the polymer-like ultrathin W18O49 nanowires (NWs) through the classical static breath figure method. By altering the concentration of the W18O49 NW dispersion, the pore size of the obtained W18O49 HMP film can be facilely tuned; this results in tunable optical modulation. The obtained W18O49 HMP film exhibits improved electrochromic properties with an optimized optical modulation of 73%, fast switching time, high coloration efficiency, and high stability even under deformation. The presented method for the fabrication of size-tunable flexible electrochromic films from ultrathin polymer-like NWs can be further extended to the fabrication of various NW-based flexible devices in the future.

This study assessed the diversity and distribution of fungal communities in thirteen marine seawater samples from four sites (L1, L3, L4 and L7) of the Mariana Trench, with a depth range of 1000–4000 meters, using Illumine Hiseq sequencing with fungal-specific primers targeting the internal transcribed spacer (ITS) region of the ribosomal rRNA gene. Sedimentary fungal communities showed high diversity with 209 880 reads belonging to 91 operational taxonomic units (OTUs). Of these OTUs, 45 belonged to the Ascomycota, 37 to Basidiomycota, 3 to Chytridiomycota, 1 to Glomeromycota, 1 to Cryptomycota, and 4 to unknown fungi. The major fungal orders included Saccharomycetales and Sporidiobolales. The commonly found fungal genera were Candida, Malassezia and Cryptococcus. These results suggest the existence of diverse fungal communities in the Mariana Trench marine seawater, which can be considered as a useful community model for further ecological and evolutionary study of fungi in the trench.

A series of quinazoline derivatives with benzylidene hydrazine carboxamide were designed and synthesised as EGFR inhibitors. Most compounds exhibited exceptional anti-proliferative activity against A549, HepG2, MCF-7 and H1975 cells. Furthermore, six compounds demonstrated excellent inhibition activity against EGFRWT with the IC50 value both less than 2 nM. Among the six compounds, 44 exhibited the strongest activity (0.4 nM) and potently inhibited EGFRL858R/T790M (0.1 μM). Excitingly, the most potent compound 14 showed excellent enzyme inhibitory activity with 6.3 nM and 8.4 nM for both EGFRWT and EGFRT790M/L858R. The result of AO single staining and Annexin V/PI staining showed that the compound 14 and 44 could induce remarkable apoptosis of A549 cells. The compound 14 arrested the cell cycle at the S phase and compound 44 arrested the cell cycle at the G0 phase in A549 cells. These preliminary results demonstrate that compound 14 and 44 may be promising lead compound-targeting EGFR.

Plant invasion is a major threat to natural ecosystems, and mangrove forests are among the most threatened ecosystems in the world. However, since mangrove species primarily occur in the saline and intertidal environment that is inhospitable for most terrestrial and freshwater plants, it is commonly assumed that mangrove forests are resilient to plant invasion. Still, many salt tolerant aquatic and terrestrial plants as well as epiphytes are found to invade the mangrove forests, and we know little about those invasive plants, their functional traits, invasion patterns and pathways and their ecological consequences. In a survey of global literature, we found a total of 57 plants reportedly invasive in the world’s mangrove forests. These plants possessed the traits of salinity tolerance, tolerance to anaerobic condition, high fecundity and rapid growth. About 19% of invasive plants were anthropogenically introduced for coastal land stabilization, and the rests were accidental introduction. Invaders were found to colonize along the forest edges or forest interior, but mostly in the raised lands. That is, the presence of diversified microhabitats such as raised land and intertidal mudflat might help both halophytic and non-halophytic plants to invade the mangrove forests. Some invaders (30%) were transient, but many (70%) could persist for a longer time; and these species could modify habitat conditions, impede natural regeneration of mangroves and disrupt their faunal assemblage. Together, plant invasion in mangrove forests is much more widespread and problematic than commonly perceived, underscoring the need for the integration of invasive plant management strategy into mangrove forest management.

In order to completely mineralization of contaminants, it is necessary to develop new methods which can effectively degrade final products of chemical oxidation. Acetic acid (HAc) has been considered one of the typical end products of chemical oxidation of pollutants and thus chosen as a representative target pollutant in the study. Nano-cerium oxide (CeO2), an environment-friendly rare-earth material, was prepared to catalytic ozonation of HAc in acidic solutions. Experimental results show that the prepared CeO2 could greatly enhance efficiency of H2O2/O3, and also have good stability and recyclability. The Raman spectra indicate that H2O2 interacts with oxygen vacancies of CeO2 to form peroxide-like species, which could effectively initiate the decomposition of ozone to produce hydroxyl radicals. A mechanism is proposed to explain the activity of peroxide-like species for the decomposition of ozone. The effects of different parameters such as initial pH value, catalyst dosage, and the concentration of H2O2 are also investigated. The results indicate that the CeO2/H2O2/O3 may provide a convenient and effective method for degrading refractory organic pollutants in acidic wastewaters.

Two laser crystals of Er3+:KLu(WO4)2 and Er3+/Pr3+:KLu(WO4)2 were successfully grown using the top-seeded solution growth technique with K2W2O7 as flux. Segregation coefficients of Er3+ ions in Er3+:KLu(WO4)2 and Er3+/Pr3+:KLu(WO4)2 crystals were 0.664 and 0.9, respectively. The density of the Pr3+ ions in the Er3+/Pr3+:KLu(WO4)2 crystal was 1.19 × 1019 cm−3, and the segregation coefficient was 0.18. The absorption and fluorescence spectra of the two crystals with Y-oriented polarization (parallel to the b axis) light were recorded. Judd–Ofelt (J–O) theory was adapted to analyze the main parameters and they were crucial for evaluating the potential of laser crystals with output wavelength of 2.7 µm. Results showed that the Er3+/Pr3+:KLu(WO4)2 crystal had good J–O intensity parameter Ωt (t = 2, 4, 6) and relatively large emission cross section at 2.7 µm. The lifetimes of the 4I11/2 state in the Er3+:KLu(WO4)2 and Er3+/Pr3+:KLu(WO4)2 crystals were fitted to be 87.13 ms and 79.36 ms, respectively. The lifetime of 4I13/2 state decreased sharply from 5.59 s in Er3+:KLu(WO4)2 to 53.19 ms with co-doping of Er3+ ions and Pr3+ ions. Laser oscillation was accomplished at 2.7 µm wavelength using a b-cut Er3+/Pr3+:KLu(WO4)2 crystal sample with size of 4 × 4 × 10 mm3. Finally, a continuous-wave (CW) laser was realized with the highest slope of 15.94%. The center wavelength of the laser output was 2740 nm, and its FWHM was approximately 1.8 nm. Therefore, the Er3+/Pr3+:KLu(WO4)2 crystal has remarkable potential for generating 2.7 µm lasers.

A novel NaI-catalyzed oxidative amination of sodium sulfinates, employing both ethylene dibromide (EDB) and air as the oxidants, is described. EDB was first demonstrated to be a promising mild organic oxidant that in air, converted NaI into molecular iodine to promote the cross-coupling reactions of aromatic sodium sulfinates with amines to produce arylsulfonamides. Mechanistic studies indicated that a radical pathway might be involved in the reaction process.

Sol-gel derived organic/inorganic hybrids, in which organic and inorganic components form co-networks at the molecular level, have demonstrated great potential for providing improved mechanical properties and biological functions in tissue engineering applications. Here, a novel bioactive hydroxyapatite-chitosan-silica hybrid (HA-CSH) scaffold was successfully fabricated by combining the sol-gel method and 3D plotting technique. Physiochemical characterization confirmed that chitosan was hybridized homogeneously with the inorganic phase on nanoscale. The obtained scaffolds possessed precisely controllable and interconnected porous structures. The nano-sized HA formed in situ and dispersed uniformly in the hybrid network, which reduced the water absorption and increased the mechanical strength of the hybrid scaffold under humidity condition as compared to chitosan-silica hybrid (CSH) scaffold. Compression tests showed that the 3D plotted hybrid scaffolds under wet conditions had compressive strengths of 10–13 MPa and elastic moduli of 21–27 MPa and thus met the mechanical requirements of human trabecular bone. Studies on the mineralization process under simulated body fluid (SBF) conditions confirmed that the introduction of HA obviously increased the biological activity of hybrid scaffolds. In vitro cell results indicated that the HA-CSH scaffold not only supported adhesion and proliferation of mouse bone mesenchymal stem cells (mBMSCs), but also improved the osteoinductivity. The alkaline phosphatase activity and mineral deposition on the HA-CSH scaffold were higher than those on the CSH scaffold. These results suggested that the 3D plotted HA-CSH scaffold may be a promising bioactive material for bone tissues regeneration.

Plant diversity has a strong impact on a plethora of ecosystem functions and services, especially ecosystem carbon (C) storage. However, the potential context-dependency of biodiversity effects across ecosystem types, environmental conditions and carbon pools remains largely unknown. In this study, we performed a meta-analysis by collecting data from 95 biodiversity-ecosystem functioning (BEF) studies across 60 sites to explore the effects of plant diversity on different C pools, including aboveground and belowground plant biomass, soil microbial biomass C and soil C content across different ecosystem types. The results showed that ecosystem C storage was significantly enhanced by plant diversity, with stronger effects on aboveground biomass than on soil C content. Moreover, the response magnitudes of ecosystem C storage increased with the level of species richness and experimental duration across all ecosystems. The effects of plant diversity were more pronounced in grasslands than in forests. Furthermore, the effects of plant diversity on belowground plant biomass increased with aridity index in grasslands and forests, suggesting that climate change might modulate biodiversity effects, which are stronger under wetter conditions but weaker under more arid conditions. Taken together, these results provide novel insights into the important role of plant diversity in ecosystem C storage across critical C pools, ecosystem types and environmental contexts.

We describe the convergent synthesis of a 5-O-β-D-ribofuranosyl-based apramycin derivative (apralog) that displays significantly improved antibacterial activity over the parent apramycin against wild-type ESKAPE pathogens. In addition, the new apralog retains excellent antibacterial activity in the presence of the only aminoglycoside modifying enzyme (AAC(3)-IV) acting on the parent, without incurring susceptibility to the APH(3’) mechanism that disables other 5-O-β-D-ribosfuranosyl 2-deoxystreptamine type aminoglycosides by phosphorylation at the ribose 5-position. Consistent with this antibacterial activity, the new apralog has excellent 30 nM activity (IC(50)) for the inhibition of protein synthesis by the bacterial ribosome in a cell-free translation assay, while retaining the excellent across-the-board selectivity of the parent for inhibition of bacterial over eukaryotic ribosomes. Overall, these characteristics translate into excellent in-vivo efficacy against E. coli in a mouse thigh infection model and reduced ototoxicity vis à vis the parent in mouse cochlear explants.

Droughts represent one of the most severe abiotic stress factors that could result in great crop yield loss. Numerous vegetation indices have been proposed for monitoring the vegetation condition under stress and assessing drought impacts on yield loss. However, the understanding and comparison between traditional vegetation indices (VIs) and the newly emerging satellite Sun-Induced Chlorophyll Fluorescence (SIF) for monitoring vegetation condition is still limited especially under drought stress and at multiple spatial scales. In this study, the potential of satellite observation SIF for monitoring corn response to drought was investigated based on the 2012 drought in the US Corn Belt. The standardized precipitation evapotranspiration index (SPEI) was used here to quantify drought. We found that all SPEI were above -1, except for July (-1.27), August (-1.39) and September (-1.14) in 2012, indicating the severity of this drought. We examined the relationship between satellite measurements of SIF, SIFyield, VIs (e.g., NDVI and EVI) and SPEI. Results indicated that SIFyield was sensitive to drought and SIF captured the stress more accurately both at the regional and state scales for the US Corn Belt. Quantitatively, SIFyield had a high correlation with SPEI (r = 0.987, p < 0.05) over the entire Corn Belt, and it indicated losses in response to drought approximately one month earlier than SIF/NDVI/EVI. Furthermore, our results demonstrated that SIF could be trusted as an effective indicator to study the relationship between GPP (R2 ≥ 0.8664, p < 0.01) under drought conditions across the Corn Belt. This study highlighted the advantage of using satellite SIF observations to monitor the drought stress on crop growth especially GPP at regional scale.

Epidermal growth factor receptor (EGFR) is a receptor for epithelial growth factor (EGF) cell proliferation and signaling, which is related to the inhibition of tumor cell proliferation, angiogenesis, tumor invasion, metastasis, and apoptosis. Thus, it has become an important target for the treatment of non-small cell lung cancer (NSCLC). The first to the third-generation EGFR inhibitors have demonstrated powerful efficacy and brought a prospect to patients. Unfortunately, after 9-15 months of treatment, they all developed resistance without exception. As for the resistance of third-generation inhibitors, no major breakthrough has been made in this field. In this review, we discussed the recent advances in medicinal chemistry of fourth-generation EGFR-TKIs, as well as further discussed the clinical challenges and future prospects of treating patients with EGFR mutations resistant to third-generation EGFR-TKIs.