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Scalable fabrication of perovskite solar cells (PSCs) with high reliability is one of the most pivotal concerns that must be addressed before they get into the photovoltaic (PV) market. Scaling large-area high-quality perovskite films is of great importance in this process. Here, gaseous therapy has been proposed for the post-treatment of perovskite films with high scalability and low cost. An inspiring evolvement from poor perovskite films to high quality ones is demonstrated under a joint treatment of methylamine gas and hot solvent vapors. The perovskite films are completely reconstructed and repaired regardless of the morphology of the original films. As a consequence, small-area (0.09 cm2) and large-area (4 cm2) PSCs based on the healed MAPbI3 films can afford J-V scanned efficiencies of 19.2 and 16.5% under a reverse sweep, respectively. Furthermore, stabilized power outputs of 18.5 and 15.2% are obtained from the small one and large one under continuous maximum power point tracking.

The mangrove-derived endophytic fungus Peniophora incarnata Z4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1-4), one new chromone (5), one new xanthone (6), and one new xanthone dimer (7), together with one known compound, globosuxanthone B (8). Their structures were determined by an extensive analysis of 1D and 2D NMR, HRESIMS, ECD, and single-crystal X-ray diffraction data. In cytotoxic activity assays, compound 2 showed cytotoxicity against three carcinoma cell lines with IC50 values less than 10 μM.

The techno-economic analysis of an IGCC power plant coupled with integrated intermittent chemical looping air separation (IICLAS) as Design 1 and an IGCC polygeneration plant integrated with chemical looping hydrogen generation (CLHG) as Design 2 are addressed. The economic evaluations show that (i) the total overnight cost of capital (TOCC) of Design 1 is higher than it of Design 2 by 3.6% and (ii) the total fixed and variable operation and maintenance cost (TOMC) of Design 1 is higher than it of Design 2 by 17.8%. These comparisons imply that the potential investment opportunities in Design 2 are more than Design 1. According to recent reports of the internal rate of return (IRR) for the coal-fired power plant investment around 8%∼12%, Design 2 guarantees the minimum acceptable IRR with 14.1% even though its revenue is reduced by 30%. For assessing the levelized cost of energy (LCOE) with 0.058USD/kWh and the dynamic payback period (DPP) with 6.6 years, these beneficial results raise the commercial potential of Design 2.

Cancer therapeutic strategies based on angiogenesis attract great attention from fundamental and clinical research. Blocking oxygen and nutrition supply to tumor cells could inhibit the growth of tumors based on occlusion of blood vessels in the tumor. Herein, we report a dual-responsive peptide-based nanoparticle, mimicking the laminin fibrillogenesis specifically and highly efficiently in tumor vessels, resulting in the blockage of tumor vessels and the growth inhibition of tumors. The laminin mimic peptide (LMMP) is designed with a fibrillation sequence, a pH-responsive sequence, and a targeting sequence. The LMMP in nanoformulations is delivered to blood vessels in the tumors, where the microenvironment (pH and microthrombus) enable LMMP to process laminin fibrillogenesis, constructing fibrous networks. The laminin-like fibrous networks capture red blood cells etc., forming occlusion specifically in the tumor blood vessels to inhibit the growth of the tumor.

Heterostructure engineering of electrode materials, which is expected to accelerate the ion/electron transport rates driven by a built-in internal electric field at the heterointerface, offers unprecedented promise in improving their cycling stability and rate performance. Herein, carbon nanotubes with Co9 S8 /ZnS heterostructures embedded in a N-doped carbon framework (Co9 S8 /ZnS@NC) have been rationally designed via an in-situ vapor chemical transformation strategy with the aid of thiophene, which not only acted as carbon source for the growth of carbon nanotubes but also as sulfur source for the sulfurization of metal Zn and Co. Density functional theory (DFT) calculation shows an about 3.24 eV electrostatic potential difference between ZnS and Co9 S8 , which results in a strong electrostatic field across the interface that makes electrons transfer from Co9 S8 to the ZnS side. As expected, a stable cycling performance with reversible capacity of 411.2 mAh g-1 at 1000 mA g-1 after 300 cycles, excellent rate capability (324 mAh g-1 at 2000 A g-1 ) and a high percentage of pseudocapacitance contribution (87.5% at 2.2 mv/s) for lithium-ion batteries (LIBs) are achieved. This work provides a possible strategy for designing multicomponent heterostructural materials for application in energy storage and conversion fields.

Sugars are abundant natural sources existing in biological systems, and bioactive saccharides have attracted much more attention in the field of biochemistry and biomaterials. For better understanding of the sugar-based biomaterials and biological sciences, aggregation-induced emission luminogens (AIE-gens) have been widely employed for detection, tracing, and imaging. This review covers the applications of AIE molecules on sugar-based biomaterials by three parts, polysaccharide, oligosaccharide, and monosaccharide, mainly focusing on saccharide detection, stimuli response materials preparation, bioimaging, and study of the AIE mechanism. These excellent works suggest the promising future of the sugar-based AIE bioconjugates, considering that the naturally designed and elaborately functionalized saccharides play discriminate roles in biological processes and AIE-tagged species may work as an indicator in each case. However, there are a lot of sugar-based biological species that have not been touched, such as mucopolysaccharides and glycoproteins on the cell surface and in the cell plasma. Based on these features, we enthusiastically look forward to more glorious developments in this bright research area.

Single-atom catalysts have found considerable applications in the field of electrochemical CO2 reduction reaction (CO2RR) due to their unique coordination environments. However, during the preparat...

Tip vortex cavitation (TVC) is an important cavitation phenomenon in marine propeller. The formation and evolution of tip vortex cavitation are hot topics consistently both in engineering application and mechanism research. In this paper some recent studies on tip vortex cavitation inception and the noise of tip vortex cavitation evolution are presented. The effects of both flow field and water qualities on tip vortex cavitation inception are considered by experiments and numerical simulations. The results show that besides the average minimum pressure in the vortex core the turbulence fluctuation and water qualities including air content and nuclei distribution have great influence on tip vortex cavitation inception. Based on the idea of first nucleus cavitating in tip vortex core new prediction formula for tip vortex cavitation inception is proposed. The synchronous technique of high speed video observation and noise measurement are adopted to study the development of tip vortex cavitation. S-type total noise characteristics are obtained when cavitation number from low to high. Vortex singing is found in the case where the tip vortex cavitation just before leaves the tip region. The excited mechanism of vortex singing is proposed by analyzing the wave propagation on the interface of vortex cavity.

The stability and existence conditions of Hopf bifurcation of a commensurate fractional-order van der Pol oscillator with time-delayed feedback are studied. Firstly, the necessary and sufficient conditions for the asymptotic stability of the equilibrium point of fractional-order van der Pol oscillator with linear displacement feedback are obtained, and it is found that the conditions are not only related to the feedback gain, but also to the fractional order. Secondly, regarding time delay as a bifurcation parameter, the stability of the commensurate fractional-order van der Pol system with time-delayed feedback is investigated based on the characteristic equation. Under some conditions, the critical value of time delay is calculated. The equilibrium point is stable when the parameter is less than the critical value and will be unstable if the parameter is greater than it. Moreover, the conditions for the occurrence of Hopf bifurcation are obtained. Finally, choosing four typical system parameters, some numerical simulations are carried out to verify the correctness of the obtained theoretical results.

Resources in urine-containing wastewater are useful if recovered as nutrients. In this study, a three-chamber resource recovery microbial fuel cell (RRMFC) is proposed to treat synthetic urine-containing wastewater with various organic pollutants and recover N, P, and S nutrients. In the treatment, urea hydrolysis was increased by microbial and electrical processes. Ions migration driven by the self-generated electric field was used to recover nutrients from the wastewater. Over one cycle (∼3 days), 99% of urea, 97% of COD, 99% of histidine, 91% of creatinine, 99% of sodium acetate, 98% of SO42−, and 99% of PO43− were removed from the wastewater, and at the same time, 42% of total nitrogen, 37% of PO43−, 59% of SO42−, and 33% of total salts were recovered in the middle chamber. This technology is very attractive for sustainable resource recovery from urine-containing wastewater.

Achimenes Pers. is well known for its floral diversity and widely used in horticulture, but its phylogenetic position is still poorly understood. And most research about the complete chloroplast genome sequence focused on the Old World species; therefore, we think it is necessary to examine taxa of the New World in more detail. This study determined the complete chloroplast genome of Achimenes cettoana H.E. Moore. The cp genome was 153,011 bp in a total length containing two inverted repeats (IRs) of 25,162 bp separated by a large single-copy (LSC) region of 84,669 bp and a small single-copy (SSC) region of 18,018 bp. The whole cp genome of A. cettoana contains 112 genes, including 79 protein-coding genes, 29 tRNA genes, and four rRNA genes. This plastid genome is firstly reported in the New World Gesneriaceae, which will be a valuable resource for future studies on breeding, conservation genetics, and phylogeny of Gesneriaceae.

This study was the first report for the complete chloroplast genome of Passiflora serrulata Jacq. (Passifloraceae). The cp genome was 149,683 bp in length contained two inverted repeats (IRs) of 25,470 bp, which were separated by large single-copy (LSC) and small single-copy (SSC) of 86,252 bp and 13,491 bp, respectively. A total of 110 functional genes were encoded, comprised 76 protein-coding genes, 30 tRNA genes, and four rRNA genes. The GC content was 37.0%. The maximum likelihood phylogenetic tree indicated that P. serrulata was recovered as the member of subg. Passiflora and most closely related to the clade formed by P. serratodigitata and P. ligularis.

A laboratory-scale study was conducted to investigate the effect of bioaugmentation (BA) and biostimulation (BS) on the remediation of oily sludge with high total petroleum hydrocarbon (TPH) content (269,000 mg/kg d.w. sludge). TPH concentration significantly decreased by 30.4% (P 0.05) in the BS treatment after 13-week incubation, and 17.0 and 9.1% of TPH was removed in the BA and control treatments (amended with sterile water only), respectively. Aliphatic and other fractions (i.e., saturated n-alkanes and cyclic saturated alkanes) were reduced in the BS treatment, whereas no decrease in aromatic hydrocarbons occurred in any treatment. Gas chromatography-mass spectrometry analysis of aliphatic fractions showed that low-chain-length alkanes (C8-C20) were the most biodegradable fractions. The BS treatment supported fungal proliferation, with Sordariomycetes and Eurotiomycetes as the dominant classes. BS increased fungal diversity and decreased fungal abundance, and changed bacterial community structure. The findings show the potential of using BS to treat oily sludge with high TPH content. Graphical abstract.

The persulfate/Fe2+ system has been proposed for the chemical oxidation for soil remediation, however, the homogeneous iron catalyst was hard to reuse which limited the further application. Cobalt oxyhydroxide (CoOOH) existed as a mineral in nature, which was environmentally friendly. Thus, in this study, CoOOH was selected as an efficient heterogeneous catalyst for peroxymonosulfate (PMS) activation to remediate oil contaminated soil by chemical oxidized reaction. 88.3% of oil at the initial concentration of 78–99 mg/kg can be removed within 24 h under the conditions of 1.0 g/L CoOOH and 0.1 M PMS at room temperature. The residual oil content was approximately 11.5 mg/kg which was lower than the standard of petroleum hydrocarbons for residential land (30 mg/kg), published by the Canadian Council of Ministers of the Environment (CCME). Specifically, the PMS/CoOOH system had a relatively high apparent reaction rate constant (0.3078 h−1), which was approximately twice that of the PS/Fe2+ system (0.1601 h−1). Furthermore, multiple radicals and reactive oxygen species (ROS), such as SO4 −, O2 − and 1O2, were involved in the oil removal oxidation reaction. Moreover, 73% total organic carbon (TOC) had been removed after the reaction. The findings of this study suggested that the oil-contaminated soil and CoOOH could both be recycled after remediation using the PMS/CoOOH system. In summary, the results indicated that CoOOH is a promising heterogeneous catalyst, and the PMS/CoOOH system could be considered as a feasible alternative to the PS/Fe2+ system for the remediation of oil-contaminated soil.

Foods supplemented with lactoferrin are an increasing trend owing to its multiple functions. Therefore, a reliable analytical method for the nutritional assessment and quality control of lactoferrin containing foods must be established. A method for the determination of native lactoferrin in milk using a HiTrapTM Heparin HP column coupled with HPLC was developed and validated. The conditions for lactoferrin enrichment in milk using the HiTrapTM Heparin HP column were optimized. A linear range of 2 to 100 mg L-1 was obtained for lactoferrin standards, with a R2 value of 0.9989. The detection limit (LOD) and quantification limit (LOQ) of the lactoferrin standards were 2.00 and 6.67 mg L-1, respectively. Considering the enrichment factor involved in the pre-treatment procedures, LOD and LOQ for detection of milk sample were 0.57 and 1.90 mg L-1, respectively. In addition, milk samples spiked with lactoferrin at three concentration levels (2, 5, and 10 mg/L) showed overall mean recovery of 88.3%, 90.2% and 95.1%, respectively. The relative standard deviations of intra-day and inter-day precision were 1.3% ~ 4.8%, and 2.1% ~ 5.7%, respectively, indicating that the present method showed good performances. Furthermore, the successful quantification of lactoferrin in raw milk and processed milk demonstrated the usefulness and effectiveness of the proposed method.

We assessed the presence of tetracyclines, quinolones, lincomycin, and streptomycin in ultra-high temperature (UHT) milk samples (n = 148) and pasteurized milk samples (n = 50) from China using an enzyme linked immunosorbent assay-based visualization microarray chip technique. The detection rates of tetracyclines, quinolones, lincomycin, and streptomycin were 4.7%, 3.3%, 2.7%, and 15.5%, respectively, in UHT milk and 16.0%, 4.0%, 2.0%, and 14.0%, respectively, in pasteurized milk. The maximum levels of tetracyclines, quinolones, lincomycin, and streptomycin in the sample were 9.06 μg kg−1, 4.06 μg kg−1, 7.66 μg kg−1, and 8.92 μg kg−1, respectively, which are lower than the maximum residue levels established in China, the Codex Alimentarius Commission, and the European Union, indicating the milk production/marketing system might be adequately controlling the antibiotic residue risk. However, considering the limited sample numbers, and relative high detection rates in spring and summer which might pose a health risk on population, control measures still need to be strictly enforced to keep these residues at safe levels.

Carbosilane side chain-equipped isoindigo–bithiophene semiconducting polymers (PII2T) have been designed and synthesized for stretchable electronics applications. Systematically tailoring the lengt...

First-principles based on density functional theory (DFT) are used to calculate the structural and electronic properties of InSe/arsenene heterostructure. The results show that the InSe/arsenene bilayer forms a type-II van der Waals heterostructure with a direct band gap of 0.876 eV, which is favorable for the separation of photogenerated electron-hole pairs. The properties of InSe/arsenene heterojunction can be effectively regulated by applying an external electric field and uniaxial strain. When an external electric field is applied, the heterostructure experiences a transition from semiconductor to metal. In addition, due to the presence of built-in electric field, the positive and negative electric fields have different effects on the electronic properties of heterostructure. When uniaxial strain is applied, the heterostructure can withstand larger tensile strain than compression strain without damaging the structure and the band gap is more easily decreased by X-direction strain. In addition, the heterostructure undergoes a direct-indirect bandgap transition under strain. When compressive strain is applied in the Y direction, especially e

It is of great significance to analyze and predict the deformation characteristics of rock engineering materials by establishing a universal damage constitutive model under freeze-thaw and loading conditions. Based on the study of statistical damage constitutive model founded under freeze-thaw and loading condition, analytical expressions of the model parameters and characteristic parameters in the stress-strain curves (i.e., elastic modulus, stress and corresponding strain at the peak point) were established under specific freeze-thaw cycles. Then, an attenuation model that complies with Newton's material cooling law was introduced to develop the relationship among elastic modulus, stress at peak point and freeze-thaw cycles. Thirdly, the formula of the peak strain under different freeze-thaw cycles was proposed by exploring the correlation between the peak strain of stress-strain curves and freeze-thaw cycles. Therefore, the determination method of the unified model parameters under different freeze-thaw cycles is proposed, then, statistical damage constitutive model under freeze-thaw and loading conditions is generalized, and the freeze-thaw mechanics test with marble was performed to verify the rationality of the model. The results show that stress-strain curves described by presented model under different freeze-thaw cycles have a good agreement with the experimental curves, especially at the peak strength point. The results can provide theoretical reference for the study of rock mechanical properties under different freeze-thaw cycles

To retrofit the traditional integrated gasification combined cycle (IGCC) plants, four plant designs using different combinations of the chemical-looping air separation (CLAS), calcium-looping (CaL), and syngas chemical-looping (SCL) are presented, where the modeling of calcium/chemical looping cycles in fast fluidized-bed and moving-bed reactors have been validated by experimental data. The IGCC polygeneration plants (Designs 1 and 2) and the IGCC power plants (Designs 3 and 4) are developed in an integration simulation platform, and their performances in terms of gross power efficiency (GPE), net thermal efficiency (NTE), carbon emission rate (CER) and water recycling rate (WRR) are evaluated. The comparison results show that (i) Design 1 possesses high thermal efficiency and low water consumption since the SCL cycle can improve NTE and increase WRR by producing the high-purity hydrogen and recovering water from exhaust gases, and (ii) Design 4 possesses high power efficiency and low CO2 emissions since a combination of Rankine and Brayton cycles is integrated to increase GPE and CO2-rich gas is partially recycled in the CLAS cycle to decrease CER.

Five isomorphic lanthanide metal-organic frameworks constructed from 5-(3-carboxy-phenyl)-pyridine-2-carboxylic acid (H2cppca) and oxalate (H2ox), {[Ln2(cppca)2(ox)(H2O)2]·2H2O}n [Ln = Eu (1), Gd (2), Nd (3), Pr (4),Tb (5)] have been successfully synthesized and characterized by single-crystal X ray diffraction, elemental analysis, IR spectroscopy, thermal analysis, and powder X-ray diffraction. In compounds 1–5, inorganic helical Ln-O chain and cppca2- anions are interconnected to form a one-dimension (1D) helical metal-organic chain, then 1D metal-organic chains are linked into a three-dimension achiral network with 1D channel of 6.31 × 10.13 A2, showing an unprecedented (4,5)-connected topology net with Schlafli symbol {44.62}{44.64.82}. Fluorescent experiment indicated that compounds 1 and 5 show sensitive luminescence quenching response to aniline, and the corresponding quenching constants (Ksv) are 2.81 × 104 M−1 and 3.14 × 104 M−1, respectively. The detection limits of aniline are 3.06 μM for 1 and 2.29 μM for 5. Moreover, compounds 1 and 5 are very stable and their reusability is relatively high and the fluorescence can be easily recovered after washing.

In this paper, we study polarization-dependent optical absorption of a graphene on the top of one-dimensional photonic crystal (1DPC), which offer a method to accurately count the number of graphene layers. The 1DPC is composed of 10 pairs of (SiO2/TiO2), and the two kinds of material is transparent, which is different from the commonly substrate with significant contrast to graphene. The absorption difference fitting formula is given by the 0–10 graphene layer. It may be applicable to other two-dimensional materials optically counting layers.

Considering the distinctions of cancer cell microenvironments, smart systems with stimulus-triggered features have become increasingly popular nowadays. These smart systems are regarded as efficient approaches for targeted cancer cell imaging and selective tumoricidal therapy. On account of the highly reductive micro-environment in tumor tissues, a redox-responsive fluorescent AIE bioprobe based on a disulfide bond is designed and synthesized. This AIE bioprobe possesses excellent water dispersibility and nano-size stability under physiological conditions. Under the reductive microenvironment of tumor cells, the water dispersibility of the AIE probe becomes worse owing to the cleavage of carboxyl groups. The dispersibility alteration further induces the aggregation of AIE nanoparticles and enhances intracellular retention, allowing for targeted imaging reinforcement and selective suppression of cancer cells.

A novel Cu(I)-cluster based coordination compound formulated as {(Cu2I2)2[Cu6(dmpymt)6]}n (Hdmpymt = 4,6-dimethylpyrimidine-2-thione) was synthesized under solvo-thermal condition and characterized by single-crystal X ray diffraction, elemental analysis, IR spectroscopy, thermal analysis, and powder X-ray diffraction. Compound 1 is an infinite 3D structure composed of Cu2I2 and Cu6S6 binary Cu(I) clusters with 66 topology, and displays high thermal stability and good solvent stability. Fluorescence experiments illustrate that compound 1 displays apparently red luminescence emission and selectively turn-off fluorescence response for CrO42− and Cr2O72− in water, showing potential luminescent probes for detecting Cr(VI) ions.

The quality of a quantum operation determines the performance of quantum information processing, such as the sensitivity of quantum sensing. Different from the fidelity of quantum operation in quantum computation, we present an effective function to evaluate the performance and diagnose the imperfection of operations in multi-pulse based quantum sensing. The evaluation function directly links the realistic sensitivity with intrinsic sensitivity in a simple way. Moreover, guided by this evaluation function, we optimize a composite pulse sequence for high sensitivity nitrogen-vacancycenter based magnetometry against spectrum inhomogeneities and control errors to improve the signal-to-noise ratio of nanoscale nuclear magnetic resonance by 1 order of magnitude. It marks an important step towards quantitative quantum sensing with imperfect quantum control in practical applications., Comment: 10 pages, 9 figures

Myo-inositol and its metabolic derivatives such as pinitol, galactinol, and raffinose affect growth and development and are also involved in stress adaptation. Previous studies have identified myo-inositol transporters (INTs) as transporters of Na+ from root to shoot in the halophyte ice plant (Mesembryanthemum crystallinum). We found that the supply of myo-inositol could alleviate the dehydration effects of salt-stressed ice plant seedlings by decreasing the Na/K ratio in roots and increasing the Na/K ratio in shoots. Analyses of the uptake of exogenous myo-inositol revealed that ice plant seedlings contained intrinsic high-affinity transporters and inducible low-affinity uptake systems. The presence of Na+ facilitated both high- and low-affinity myo-inositol uptake. Six INT genes were identified from the ice plant transcriptome and named McINT1a, 1b, 2, 4a, 4b, and 4c, according to the classification of the Arabidopsis INT family. In seedlings treated with myo-inositol, salt, or myo-inositol plus salt, the expression patterns of all McINT members differed in shoot and root, which indicates organ-specific regulation of McINTs by salt and myo-inositol. The expression of McINT2, 4a, 4b, and 4c was induced by salt stress in shoot and root, but that of McINT1a and 1b was salt-induced only in shoot. The expression of pinitol biosynthesis gene IMT1 was induced by salt and myo-inositol, and their combination had a synergistic effect on the accumulation of pinitol. Supply of myo-inositol to salt-treated seedlings alleviated the detrimental effects by maintaining a low root Na/K ratio and providing precursors for the synthesis of compatible solute to maintain the osmotic balance.

The nonlinear fluorescence emission has been widely applied for high spatial resolution optical imaging. Here, we studied the fluorescence anomalous saturating effect of the nitrogen vacancy defect in diamond. The fluorescence reduction was observed with high power laser excitation. It increased the nonlinearity of the fluorescence emission, and changed the spatial frequency distribution of the fluorescence image. We used a differential excitation protocol to extract the high spatial frequency information. By modulating the excitation laser’s power, the spatial resolution of imaging was improved approximately 1.6 times in comparison with the confocal microscopy. Due to the simplicity of the experimental setup and data processing, we expect this method can be used for improving the spatial resolution of sensing and biological labeling with the defects in solids.

Primulina spiradiclioides Z.B. Xin & F. Wen (Gesneriaceae), a new species from limestone areas in Guangxi, China, is described and illustrated. It resembles P. curvituba, but can be easily distinguished from it by several characters, especially by its straight corolla tube. We found only one population with fewer than 200 mature individuals at the type locality.

Mountain systems harbor a substantial fraction of global biodiversity and, thus, provide excellent opportunities to study rapid diversification and to understand the historical processes underlying the assembly of biodiversity hotspots. The rich biodiversity in mountains is widely regarded as having arisen under the influence of geological and climatic processes as well as the complex interactions among them. However, the relative contribution of geology and climate in driving species radiation is seldom explored. Here, we studied the evolutionary radiation of Oreocharis (Gesneriaceae), which has diversified extensively throughout East Asia, especially within the Hengduan Mountains (HDM), using transcriptomic data and a time calibrated phylogeny for 88% (111/126) of all species of the genus. In particular, we applied phylogenetic reconstructions to evaluate the extent of incomplete lineage sorting accompanying the early and rapid radiation in the genus. We then fit macroevolutionary models to explore its spatial and diversification dynamics in Oreocharis and applied explicit birth–death models to investigate the effects of past environmental changes on its diversification. Evidence from 574 orthologous loci suggest that Oreocharis underwent an impressive early burst of speciation starting ca. 12 Ma in the Miocene, followed by a drastic decline in speciation toward the present. Although we found no evidence for a shift in diversification rate across the phylogeny of Oreocharis, we showed a difference in diversification dynamics between the HDM and non-HDM lineages, with higher diversification rates in the HDM. The diversification dynamic of Oreocharis is most likely positively associated with temperature-dependent speciation and dependency on the Asian monsoons. We suggest that the warm and humid climate of the mid-Miocene was probably the primary driver of the rapid diversification in Oreocharis, while mountain building of the HDM might have indirectly affected species diversification of the HDM lineage. This study highlights the importance of past climatic changes, combined with mountain building, in creating strong environmental heterogeneity and driving diversification of mountain plants, and suggests that the biodiversity in the HDM cannot directly be attributed to mountain uplift, contrary to many recent speculations.[East Asian monsoons; environmental heterogeneity; Hengduan Mountains; incomplete lineage sorting; Oreocharis; past climate change; rapid diversification; transcriptome.]

In this study, the InSb/InSe heterostructure is systematically examined in terms of its electronic properties through first-principles calculations. According to our findings, the InSb/InSe heterostructure is a kind of unique direct band gap semiconductor, which has inherent type-II band alignment, resulting in significant photogenerated electron–hole pair separation in space. When the external electric field is applied, the Stark effect is observed in the band gap. Interestingly, in the application of the −0.3 V A−1 electric field, such a heterostructure is transformed into type-I from type-II. Simultaneously, the band gap is also effectively controlled by uniaxial strain. In particular, high carrier mobility is obtained at a compressive strain of 4% on the Y-axis. To sum up, based on the results in the present work, the InSb/InSe heterostructure can be potentially used in nanoelectronic and optoelectronic devices.

Cesium (Cs) contained triple-cation and mixed halide perovskite (CsFAMA) is broadly employed as light absorption layers for efficient and stable perovskite solar cells (PSCs) fabrication with high reproducibility. On the other hand, thermal annealing is a universal post-treatment method for perovskite films preparation. Moreover, thermal management highly depends on perovskite materials. However, no specialized study has been reported on CsFAMA perovskite to date. Herein, we have systematically investigated the influence of thermal annealing and annealing time on CsFAMA films and their solar cells. We demonstrated that heating time of 45 or 60 min at 100 °C is desirable. More interestingly, we found that the unannealed CsFAMA films exhibit ultrahigh photoluminescence (PL) intensities, much stronger than that of annealed films. Note that PL intensities gradually weaken as a function of annealing time. In particular, the PL intensities of fresh films (after antisolvent dripping) are at least 200 times higher than that of 60 min annealed films. To our knowledge, it is the first time to report this PL behavior. We speculate that it is due to quantum confinement effect of perovskite crystal nuclei and "cage effect" of DMSO intermediates in the fresh films. To this point, the unannealed CsFAMA films may have great potential in PL emission applications.

Light has shown up an incredibe capability in precision measurement based on opto-mechanic interaction in high vacuum by isolating environment noises. However, there are still obstructions, such as displacement and mass estimation error, highly hampering the improvement of absolute accuracy at the nanoscale. Here, we present a nonlinearity based metrology to precisely measure the position and mass of a nanoparticle with optical levitation under $10^{-5}$ mbar, 6-order of magnitude lower than the electrostatic-force and stochastic-force-based counterparts. By precisely controlling the amplitude of the levitated nanoparticle at the nonlinear regime, we realized a feasible sub-picometer-level position measurement with an uncertainty of $1.0\%$ without the prior information of mass, which can be further applied to weigh the femtogram-level mass with an uncertainty of $2.2\%$. It will also pave the way to construct a well-calibrated opto-mechanic platform in high vacuum for high sensitivity and accuracy measurement in force and acceleration at the nanoscale and the study in quantum superposition at the mesoscopic scale., Comment: 9 pages, 6 figures

Two new 2-carboxymethyl-3-hexyl-maleic anhydride derivatives, arthrianhydride A (1) and B (2), along with three known compounds 3-5, were isolated from the fermentation broth of a grasshopper-associated fungus Arthrinium sp. NF2410. The structures of new compounds 1 and 2 were determined based on the analysis of the HR-ESI-MS and NMR spectroscopic data. Furthermore, compounds 1 and 2 were evaluated on inhibitory activity against the enzyme SHP2 and both of them showed moderate inhibitory activity against SHP2.

We propose DiscoFaceGAN, an approach for face image generation of virtual people with disentangled, precisely-controllable latent representations for identity of non-existing people, expression, pose, and illumination. We embed 3D priors into adversarial learning and train the network to imitate the image formation of an analytic 3D face deformation and rendering process. To deal with the generation freedom induced by the domain gap between real and rendered faces, we further introduce contrastive learning to promote disentanglement by comparing pairs of generated images. Experiments show that through our imitative-contrastive learning, the factor variations are very well disentangled and the properties of a generated face can be precisely controlled. We also analyze the learned latent space and present several meaningful properties supporting factor disentanglement. Our method can also be used to embed real images into the disentangled latent space. We hope our method could provide new understandings of the relationship between physical properties and deep image synthesis., Accepted by CVPR2020 (Oral)

Mycotoxins are a large type of secondary metabolites produced by fungi that pose a great hazard to and cause toxic reactions in humans and animals. A majority of countries and regulators, such as the European Union, have established a series of requirements for their use, and they have also set maximum tolerance levels. The development of high sensitivity and a specific analytical platform for mycotoxins is much in demand to address new challenges for food safety worldwide. Due to the superiority of simple, rapid, and low-cost characteristics, aptamer-based biosensors have successfully been developed for the detection of various mycotoxins with high sensitivity and selectivity compared with traditional instrumental methods and immunological approaches. In this article, we discuss and analyze the development of aptasensors for mycotoxins determination in food and agricultural products over the last 11 years and cover the literatures from the first report in 2008 until the present time. In addition, challenges and future trends for the selection of aptamers toward various mycotoxins and aptasensors for multi-mycotoxins analyses are summarized. Given the promising development and potential application of aptasensors, future research studies made will witness the great practicality of using aptamer-based biosensors within the field of food safety.

We propose to restore old photos that suffer from severe degradation through a deep learning approach. Unlike conventional restoration tasks that can be solved through supervised learning, the degradation in real photos is complex and the domain gap between synthetic images and real old photos makes the network fail to generalize. Therefore, we propose a novel triplet domain translation network by leveraging real photos along with massive synthetic image pairs. Specifically, we train two variational autoencoders (VAEs) to respectively transform old photos and clean photos into two latent spaces. And the translation between these two latent spaces is learned with synthetic paired data. This translation generalizes well to real photos because the domain gap is closed in the compact latent space. Besides, to address multiple degradations mixed in one old photo, we design a global branch with a partial nonlocal block targeting to the structured defects, such as scratches and dust spots, and a local branch targeting to the unstructured defects, such as noises and blurriness. Two branches are fused in the latent space, leading to improved capability to restore old photos from multiple defects. The proposed method outperforms state-of-the-art methods in terms of visual quality for old photos restoration., Comment: CVPR 2020 Oral, project website: http://raywzy.com/Old_Photo/

We present a general framework for exemplar-based image translation, which synthesizes a photo-realistic image from the input in a distinct domain (e.g., semantic segmentation mask, or edge map, or pose keypoints), given an exemplar image. The output has the style (e.g., color, texture) in consistency with the semantically corresponding objects in the exemplar. We propose to jointly learn the crossdomain correspondence and the image translation, where both tasks facilitate each other and thus can be learned with weak supervision. The images from distinct domains are first aligned to an intermediate domain where dense correspondence is established. Then, the network synthesizes images based on the appearance of semantically corresponding patches in the exemplar. We demonstrate the effectiveness of our approach in several image translation tasks. Our method is superior to state-of-the-art methods in terms of image quality significantly, with the image style faithful to the exemplar with semantic consistency. Moreover, we show the utility of our method for several applications, Comment: Accepted as a CVPR 2020 oral paper

A novel pillared-layer coordination polymer containing -Pb-O-Pb-Cu-Cl- inorganic sheets, [PbCuCl(3.5-pydc)]n (1) (3.5-H2pydc = pyridine-3,5-dicarboxylic acid), was obtained through the hydrothermal method. In compound 1, two symmetry-related Pb centers are bridged into a Pb2O2 dimer by two symmetrically carboxyl oxygen atoms from 3,5-pydc2− anions, each Pb2O2 dimer links four equivalent units into a 2D puckered Pb-O-Pb layer. Two symmetry-related Cu ions are bridged into a Cu2Cl2 dimer by two chlorine ions. Thus the -Pb-O-Pb- layer and Cu2Cl2 dimers are joined into a novel 2D puckered -Pb-O-Pb-Cu-Cl- inorganic layer. The 2D -Pb-O-Pb-Cu-Cl- inorganic layers are further pillared to form a 3D network through 3,5-pydc2− anions. To the best of our knowledge, the pillared-layer framework based on -Pb-O-Pb-Cu-Cl- inorganic layers has never been reported previously. Compound 1 exhibits weak blue light emission with the maximum at 383 nm upon excitation at 260 nm.

Practical quantum information technique requires a large scalable quantum network. We proposed a hybrid system for deterministic scalable spin entanglement network based on nitrogen-vacancy (NV) centers in diamond coupling with carbon nanotube. The fault-tolerant entangled gate between two remote NV centers can be realized with vibrating nanotube assisted spin-spin interaction with current experimental technology. This interaction can be directly generalized to multi-NV-center entanglement architecture. Moreover, the effects of the single spin dephasing (SSD) and spin cross relaxation (SCR) on this state generation process were analyzed in detail. We found that the decay rate scales as ${N}^{2}$, corresponding to the number of independent decoherence channels. However, by employing dressed state protection and independent tunable interaction method, SSD and SCR can be mitigated efficiently and the decay rate of the generated multi-NV-center entanglement scales as $N$, which boosts the size of the entanglement network up to hundreds of qubits. Such a hybrid quantum system compatible with current topological protection provides a useful platform for the investigation of quantum computation.

Productivity from day one on supercomputers that leverage new technologies requires significant preparation. An institution that procures a novel system architecture often lacks sufficient institutional knowledge and skills to prepare for it. Thus, the "Center of Excellence" (CoE) concept has emerged to prepare for systems such as Summit and Sierra, currently the top two systems in the Top 500. This paper documents CoE experiences that prepared a workload of diverse applications and math libraries for a heterogeneous system. We describe our approach to this preparation, including our management and execution strategies, and detail our experiences with and reasons for using different programming approaches. Our early science and performance results show that the project enabled significant early seismic science with up to a l4X throughput increase over Cori. In addition to our successes, we discuss our challenges and failures so others may benefit from our experience.

The oleaginous alga Botryococcus braunii (Chlorophyta) is known to accumulate hydrocarbons up to 80% of cell dry weight. Races A, B, and L of B. braunii species accumulate alkadiene/triene, botryococcene, and lycopadiene, respectively. Transcriptome analyses in race A and race B have identified various transcripts encoding enzymes involved in the biosynthesis of alkadiene/triene and botryococcene. However, the transcriptome of B. braunii race L has not been analyzed. In this study, we report the de novo assembly of the transcriptome of B. braunii AC768 race L. AC768 culture in 2×BB medium reaches a maximum density (cell dry weight) of 5.5 g L−1, of which, 6% is lycopadiene. Transcriptional profiles of AC768 show that ESTs involved in energy metabolisms are most abundantly expressed, suggesting an energy requirement for lipid accumulation. Transcriptomic analysis indicates the presence of a putative lycopaoctaene synthase that synthesizes the precursor of lycopadiene in AC768. Comparative analysis between races reveals that botryococcene synthase and lycopaoctaene synthase are specific to races B and L of B. braunii, respectively. Taken together, our results indicate that hydrocarbon chemicals accumulated in different races of B. braunii are determined by their transcriptional profiles.

High spatial resolution and low perturbation are required for mapping the electromagnetic field at the nanoscale, to provide crucial information about local light-matter interaction. Using optical superresolution microscopy for detection via a nitrogen-vacancy center in diamond, this work demonstrates far-field noninvasive sensing of the local electromagnetic field with high accuracy and a spatial resolution of approximately 50 nm. As the nitrogen-vacancy center is sensitive to various physical quantities, a multifunctional far-field quantum nanoscope is anticipated.

Primulina cangwuensis X. Hong & F. Wen (Gesneriaceae), a new species growing in rocky crevices on a limestone hill in Guangxi, China, is described and illustrated. It is morphologically similar to P. repanda, P. subulata, P. jianghuaensis and P. lobulata, but can be distinguished from its congeners by the different shape of leaves, bracts and calyx, as well as by the different indumentum of pedicels and stamens.

Non-reciprocal devices, which allow the non-reciprocal signal routing, serve as the fundamental elements in photonic and microwave circuits and are crucial in both classical and quantum information processing. The radiation-pressure-induced coupling between light and mechanical motion in traveling wave resonators has been exploited to break the Lorentz reciprocity, realizing non-reciprocal devices without magnetic materials. Here, we experimentally demonstrate a reconfigurable nonreciprocal device with alternative functions of either a circulator or a directional amplifier via the optomechanically induced coherent photon-phonon conversion or gain. The demonstrated device exhibits considerable flexibility and offers exciting opportunities for combining reconfigurability, non-reciprocity and active properties in single photonic structures, which can also be generalized to microwave as well as acoustic circuits., 13 pages, 4 Figures

Paraboea wenshanensis is a new species of Gesneriaceae from Yunnan, China and is described and illustrated here. It is morphologically similar to P. angustifolia, P. martinii and P. glutinosa, but the congeners of this new taxon can be distinguished by several salient characters. A description of P. wenshanensis, together with illustrations and photographs, a distribution map and conservation assessment are presented.

This paper presents the development and application of a sensitive and specific method for the analysis of multi-mycotoxins in raw milk using ultrahigh performance liquid chromatography quadrupole orbitrap mass spectrometry (UHPLC/Q-Orbitrap). Mycotoxins (a total of 14) included in this study were aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, aflatoxin M1, aflatoxin M2, ochratoxin A, ochratoxin B, zearalenone, zearalanone, α-zeralanol, β-zeralanol, α-zeralenol, and β-zeralenol. Mycotoxins in milk were extracted and purified with a multi-mycotoxins AOZ immunoaffinity column in a single run, which made the matrix effect be negligible. The deliberate addition of small amount of acetonitrile was found to be beneficial for the extraction of mycotoxins from the complex milk matrix, especially for zearalenone and its derivatives. The final reconstituted extracts were analyzed using ultra high performance liquid chromatography coupled to quadrupole orbitrap mass spectrometry (UHPLC Q-Orbitrap mass spectrometry). The extraction recoveries are in the range of 60–106%, with coefficient of variation

In this paper, the bifurcation and chaotic behaviors of a Duffing oscillator with delayed displacement and velocity feedbacks under harmonic excitation are investigated. The analytically necessary condition for the chaos in the sense of Smale horseshoes is established based on Melnikov method. It could be found that the delayed displacement and velocity feedbacks affect the necessary condition respectively, so that the analysis on the effects of the two kinds of feedbacks is presented individually. The effects of displacement feedback coefficient, velocity feedback coefficient and their time delays on the analytically necessary condition are analytically discussed. Furthermore, some typical numerical results, including the bifurcation diagrams, Poincare maps and the largest Lyapunov exponents of the delayed oscillator are also presented and compared. The satisfactory qualitative agreement between the analytical and numerical results verify the correctness of the analytically necessary condition.

The performance of organic-inorganic perovskite solar cells depends largely on the quality of perovskite film. Currently, various methods are applied to prepare the perovskite film. Among them, the two-step method is counted as a promising candidate to obtain high-quality perovskite film. In this study, we attain a special platelet-like PbI2 films by applying pure water to cover wet PbI2 film and standing for a period of time. The unique morphology contributes to the entry of organic cations solution into the PbI2 and promoting its reaction with PbI2, which reducing the residual amount of PbI2 in the perovskite film. Compared to the traditional two-step method, water processing method can obtain a high-quality perovskite film with enlarged grain size, improved crystallization, and prolonged carrier lifetime. As a result, the efficiency of the prepared device based on the film has increased from 17.90% without water processing to 20.14% of water processing. Which demonstrates that this solvent engineering for PbI2 film opens up a possibility to prepare high-quality perovskite in a two-step method and obtain highly efficient perovskite solar cells.