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The late Permian to Early Triassic volcano-sedimentary succession associated with the Emeishan Large Igneous Province (LIP) is well preserved in the Binchuan area, Southwest China. This paper presents coupled zircon U-Pb age, trace element, and Hf isotope analyses from the succession, together with whole-rock geochemical compositions, to reveal the origin and evolution of volcanic rocks of the LIP. Zircons from the matrix and a rhyolite clast in the Lower Triassic conglomerate bed yield identical U-Pb ages of ca. 260 Ma and have geochemical affinities to those crystallized from within-plate magmas. These features, combined with the dominance of rhyolite clasts from this horizon, imply a source related to Emeishan silicic volcanic rocks. Zircons from silicic ignimbrite and rhyolite in the upper volcanic succession of the LIP display high eHf(t) values (+4.2 to +12.9), low Th/Nb and U/Yb ratios, and similar eNd(t) values (−0.17 to +0.47) to high-Ti basalts. These chemical and isotopic characteristics are consistent with the eroded silicic volcanic rocks, indicating that the late-stage silicic volcanic rocks were generated by fractionation of high-Ti basaltic magmas without significant crustal contamination. Although the late Permian zircons from the lower and upper low-Ti basalt successions all show arc-like geochemical characteristics with high Th/Nb and U/Yb ratios, the former has much lower eHf(t) values (−11.7 to −3.6) than the latter (+4.4 to +11.6), and the zircons from the upper low-Ti basalt succession show positive eHf(t) values similar to the studied rhyolites. Samples from the lower low-Ti basalt succession have relatively higher eNd(t) values (−2.66 to +3.38) than those from the upper low-Ti basalt succession (−4.48 to −0.82). These geochemical features indicate the early-stage low-Ti basalts may be mainly derived from a previously enriched subcontinental mantle lithosphere, whereas the late-stage low-Ti basalts may be generated from the increasing involvement of asthenospheric mantle source with crustal contamination.

In view of the dynamic instability of rock mass in high geostress areas during underground engineering excavation, the comprehensive weight and extension methods are adopted to research the rockburst prediction. Firstly, five main influencing factors including uniaxial compressive strength, stress coefficient, brittleness coefficient, elastic energy index, and integrity of rock mass are used as the evaluation indexes of rockburst prediction according to the conditions required for rockburst occurrence. The assessment index system of rockburst intensity is constituted. Secondly, the analytic hierarchy process (AHP) and variation coefficient methods are used to determine the comprehensive weight of evaluation index, and the rockburst prediction model is established based on the extension evaluation method. Thirdly, the parameter programming and numerical calculation of the proposed prediction model are carried out in the MATLAB software. The user visualization execution window and software system of rockburst prediction model are realized. Finally, the software system is applied to the rockburst prediction in the water diversion tunnels of Jiangbian hydropower station and Jinping secondary hydropower station. The prediction results are compared with the actual situation and other evaluation methods. The results show that (i) the establishment of the user visualization window realizes the visualization and systematization of rockburst prediction model, which improves the data import rate and calculation efficiency. (ii) The prediction results of the proposed software system agree well with the actual situation, and they are more accurate than other evaluation methods. (iii) The proposed software system of rockburst prediction can also be used in coal mine, metro, and other underground projects, which has good engineering application values.

Mechanization and automation of the coal industry as well as increasing the government support for safety in coal mines in China resulted in a significant decrease in the death rate per million tons of coal produced. Nonetheless, major accidents still occur. As one of the five factors of safe production, safety investment plays a key role in ensuring the safe production of coal in mining enterprises. Coal mining enterprises can ensure safe production in the mines and maximize profits through optimum safety investment. In this study, safety system engineering principles and subsets in set theory were combined to develop a novel safety investment index system. The safety investment indices were categorized into human, machine, environment, and the intersection of these three indices. The elements in each investment set were examined, and a multivariate model of safety investment and accident control was created using gray forecasting theory. In addition, a case study was conducted to validate the reliability of the model. The results indicated that the proposed model can provide theoretical evidence and guidance for safety investment decision making in coal mining enterprises.

Tubulin polymerisation inhibitors exhibited an important role in the treatment of patients with prostate cancer. Herein, we reported the medicinal chemistry efforts leading to a new series of benzothiazoles by a bioisosterism approach. Biological testing revealed that compound 12a could significantly inhibit in vitro tubulin polymerisation of a concentration dependent manner, with an IC50 value of 2.87 μM. Immunofluorescence and EBI competition assay investigated that compound 12a effectively inhibited tubulin polymerisation and directly bound to the colchicine-binding site of β-tubulin in PC3 cells. Docking analysis showed that 12a formed hydrogen bonds with residues Tyr357, Ala247 and Val353 of tubulin. Importantly, it displayed the promising antiproliferative ability against C42B, LNCAP, 22RV1 and PC3 cells with IC50 values of 2.81 μM, 4.31 μM, 2.13 μM and 2.04 μM, respectively. In summary, compound 12a was a novel colchicine site tubulin polymerisation inhibitor with potential to treat prostate cancer.

We report observations of photopolymerization driven phase-separation in a mixture of a photo-reactive monomer and inorganic nanoparticles. The mixture is irradiated with visible light possessing a periodic intensity profile that elicits photopolymerization along the depth of the mixture, establishing a competition between photo-crosslinking and thermodynamically favorable phase-separating behavior inherent to the system. In situ Raman spectroscopy was used to monitor the polymerization reaction and morphology evolution, and reveals a key correlation between irradiation intensity and composite morphology extending the entire depth of the mixture, i.e. unhindered phase-separation at low irradiation intensity and arrested phase-separation at high irradiation intensity. 3D Raman volume mapping and energy dispersive X-ray mapping confirm that the intensity-dependent irradiation process dictates the extent of phase separation, enabling single-parameter control over phase evolution and subsequent composite morphology. These observations can potentially enable a single-step route to develop polymer-inorganic composite materials with tunable morphologies.

Karst caves are often encountered during karst tunnel excavation, and the shape of the karst cave has an impact on the stability of the tunnel surrounding rock. This paper focused on the e...

Late Jurassic NE-trending A-type granitoids are widespread in the Shihang belt, South China, though their petrogenesis and geodynamic settings remain controversial. The Guiping complex is located on the southwest margin of the Shihang belt. In this study, the petrography, major and trace element geochemistry, whole-rock Sr-Nd isotopes, and zircon U-Pb geochronology of the Guiping complex were investigated. The Guiping complex is composed of the Fenghuangling and Xishan plutons, both plutons yielded zircon U-Pb ages of ca. 160 Ma. The Fenghuangling pluton has low SiO2 content of 54.26% to 60.31%, whereas the Xishan pluton exhibits high SiO2 content of 65.19% to 71.18%. Both of them are metaluminous and belong to the high-K calc-alkaline series and are enriched in large-ion lithophile elements (LILEs) such as Rb, Th, U, and Pb. The Fenghuangling and Xishan plutons showed enrichment in light rare earth elements (LREEs) and high-field strength elements (Nb, Ta, Zr, and Hf) and depletion in heavy rare earth elements (HREEs). Marked Nb and Ta negative anomalies were not observed. Due to the high contents of Zr + Ce + Nb + Y and high Ga/Al ratios, all the samples belonged to the group of A-type granites. The Fenghuangling and Xishan plutons had low ISr (mainly in the range of 0.7046–0.7058) and high εNd(t) (−0.60 to 1.94) values, though obviously different from those of the Precambrian basement in South China. Furthermore, they lie between the ocean island basalt (OIB) of the asthenosphere and the arc basaltic rocks of the enriched lithospheric mantle. Therefore, we proposed that the basaltic parental magma of the Guiping complex originated from partial melting of the enriched lithospheric mantle, which was metasomatized by asthenosphere-related OIB-type basaltic magma. Mafic microgranular enclaves in the Xishan pluton displayed positive Nb and Ta anomalies, which is consistent with OIB-type basalts. The enclaves also had similar Sr-Nd isotopic compositions to the Xishan pluton. That indicated that the enclaves were probably formed by mixing of the OIB-type basaltic magma and the Xishan pluton. In conclusion, the formation of the Late Jurassic NE-trending A-type granite belt was attributed to back-arc extension as a result of the rollback of the Paleo-Pacific Plate.

The contemporaneous mafic and intermediate dikes of a continental magmatic arc provide a window into the magma feeding system at depth. Here we integrate data on the elemental and Sr-Nd-Hf isotope geochemistry, petrology, mineralogy, and zircon geochronology of late Permian dikes in the East Kunlun Orogen, northern Tibetan Plateau, discuss the petrogenesis of the dikes, and reconstruct the nature and relationship of different magma reservoirs. The dikes are porphyritic diabases, lamprophyres and diorite porphyries that crystallized between 259 and 255 Ma, coeval with their host granodiorites. Geochemical and Sr-Nd-Hf isotopic data indicate the parental magma of the porphyritic diabases and lamprophyres was derived from enriched lithospheric mantle. This magma underplated the crust and underwent varying degrees of magma recharging, crustal assimilation, and fractional crystallization dominated by olivine, pyroxene, and hornblende. This evolved basaltic magmas ascended through the crust, undergoing further differentiation, and some magma entered mid-crustal reservoirs occupied by felsic crystal mushes, rejuvenating the mushes. The subsequent mixing of mafic and felsic materials formed the precursor magmas of the intermediate dikes. Our new data reveal that the magmas stagnated mainly in reservoirs at two levels, 26–32 and 9–18 km, based on hornblende barometry. The underplating, assimilation, and replenishment of basaltic magmas in the lower crust, and their eventual emplacement and differentiation in a mid-crustal reservoir, controlled the mineralogy and geochemistry of the mafic dikes, while the rejuvenation of crystal mushes, the mixing of mafic and felsic materials, and differentiation account for the compositional features of the diorite porphyries. This study shows that the trans-crustal magma feeding system, which controls the compositions of several dispersed but interconnected magma reservoirs, is the key to understanding the compositional diversity and igneous petrogenesis in continental arcs.

The Yili Block is one of the major Precambrian microcontinents of the Central Asian Orogenic Belt (CAOB). Detrital zircon U-Pb ages and Hf isotopic data of the Meso-Neoproterozoic (meta)-sedimentary units within the Yili Block constrain the tectonic affinity and early history of the block. Detrital zircon U-Pb ages, in combination with related magmatic age data, indicate that the Tekesi and Kusitai groups were deposited during the latest Mesoproterozoic-earliest Neoproterozoic (1040–960 Ma) and early Neoproterozoic (

The Yili Block in NW China and NE Kazakhstan is a continental fragment within the Central Asian Orogenic Belt (CAOB). We present a systematic study of whole-rock geochemistry, Sr–Nd–Hf isotopic compositions, and U–Pb geochronology of newly identified Neoproterozoic granitic plutons from the southern Yili Block to further constrain the Proterozoic evolution of microcontinents constituting the CAOB. Gneissic, augen, and mylonitized granites yield intrusion 206Pb/238U ages of 947 ± 4 Ma, 889 ± 5 Ma, and 892 ± 5 Ma, respectively. The gneissic granites display affinities to calc-alkaline, weakly peraluminous, magnesian I-type granites (Mg# = 33–34; FeOT/MgO = 3.49–3.59). The augen and mylonitized granites lie on the ferroan, calc-alkaline, highly fractionated A-type granite trend (Mg# = 11–21, FeOT/MgO = 6.52–14.58, SiO2 > 74 wt%, 10000*Ga/Al = 2.80–3.26). The markedly enriched Sr–Nd–Hf isotopic compositions of the ca. 947 Ma magnesian I-type granites suggest a derivation from ca. 2.0 Ga MgO-rich basement rocks. The varied initial 87Sr/86Sr ratios (0.716530–0.720543), chondrite-like eHf(t) values (−2.11 to 0.72), and differentiated incompatible elements of the ca. 890 Ma A-type granites suggest a derivation from partial melting of ca. 1.8 Ga crustal sources, followed by strong fractional crystallization. The Yili Block probably constituted part of an exterior orogen that developed along the margin of the Rodinia supercontinent during the early Neoproterozoic, undergoing a tectonic transition from syn-collisional to post-collisional extension at ca. 890 Ma. This study reveals that crustal reworking played a key role in Neoproterozoic crustal evolution in the Yili Block and that this block has a tectonic affinity to the Central Tianshan Block but is distinct from the Tarim Craton.

We report that transparent polymer coatings imprinted with tilted planar waveguides significantly reduce optical loss caused by the scattering of incident light by front metal contacts of solar cel...

The 87Sr/86Sr minimum of the Capitanian seawater is one of the most significant features in the Phanerozoic seawater 87Sr/86Sr history. In order to assess possible contribution of the Emeishan large igneous provinces (LIPs) to strontium isotope evolution of the Capitanian seawater, 87Sr/86Sr ratios were measured from the Capitanian limestones which are locally interlayered with the Emeishan basalts. The limestones underlying the Emeishan basalts have high 87Sr/86Sr ratios (0.7070–0.7074). However, extremely low 87Sr/86Sr ratios (0.7068–0.7070) were identified in the late Capitanian Jinogondolella prexuanhanensis–J. xuanhanensis zones, which correspond to the eruption time of the Emeishan LIP. The temporal coincidence of these two phenomena supports the idea of a potential linkage between Capitanian 87Sr/86Sr minimum and eruption of this igneous province. The strong submarine hydrothermal activity and erosion of the Emeishan LIP could have released large amounts of non-radiogenic Sr to the oceans and play an important role in strontium isotope evolution of the seawater.

Background The same species of plant can exhibit very diverse sizes and shapes of organs that are genetically determined. Characterising genetic variation underlying this morphological diversity is an important objective in evolutionary studies and it also helps identify the functions of genes influencing plant growth and development. Extensive screens of mutagenised Arabidopsis populations have identified multiple genes and mechanisms affecting organ size and shape, but relatively few studies have exploited the rich diversity of natural populations to identify genes involved in growth control. Results We screened a relatively well characterised collection of Arabidopsis thaliana accessions for variation in petal size. Association analyses identified sequence and gene expression variation on chromosome 4 that made a substantial contribution to differences in petal area. Variation in the expression of a previously uncharacterised gene At4g16850 (named as KSK) had a substantial role on variation in organ size by influencing cell size. Over-expression of KSK led to larger petals with larger cells and promoted the formation of stamenoid features. The expression of auxin-responsive genes known to limit cell growth was reduced in response to KSK over-expression. ANT expression was also reduced in KSK over-expression lines, consistent with altered floral identities. Auxin responses were reduced in KSK over-expressing cells, consistent with changes in auxin-responsive gene expression. KSK may therefore influence auxin responses during petal development. Conclusions Understanding how genetic variation influences plant growth is important for both evolutionary and mechanistic studies. We used natural populations of Arabidopsis thaliana to identify sequence variation in a promoter region of Arabidopsis accessions that mediated differences in the expression of a previously uncharacterised membrane protein. This variation contributed to altered auxin responses and cell size during petal growth.

In semiconductor manufacturing, defects detecting and analyzing are one of the key contributors for process yield improvement. A system is proposed to classify the defects automatically, which is more efficient than traditional manual work. It becomes possible to control the process promptly. The proposed system has three main parts, the defect image pre-process module, the defect classification module and the network results post-process module. The convolutional neural network (CNN) is used as the base algorithm for defect classification. And the post-process part is developed to refine the confusing images results. The dataset in this work are all collected from the 12-inch process line and the results show that the system proposed is a good candidate for saving massive human work.

Customer awareness and interest in mobile payments are increasing. However, security and privacy risks remain major barriers to their adoption, with customers worrying about their personal data being hacked or intercepted. In this paper, we present the design of a secure scheme for mobile payments that can guarantee mutual nonrepudiation between the customer, merchant, and banker. A customer can use the proposed scheme to make a payment with the same PayWord chains of a single account from multiple devices.

Microfiber optic array structures are fabricated and employed as an optical structure overlaying a front-contact silicon solar cell. The arrays are synthesized through light-induced self-writing in a photo-crosslinking acrylate resin, which produces periodically spaced, high-aspect-ratio, and vertically aligned tapered microfibers deposited on a transparent substrate. The structure is then positioned over and sealed onto the solar cell surface. Their fiber optic properties enable collection of non-normal incident light, allowing the structure to mitigate shading loss through the redirection of incident light away from contacts and toward the solar cell. Angle-averaged external quantum efficiency increases nominally by 1.61%, resulting in increases in short-circuit current density up to 1.13 mA/cm2. This work demonstrates a new approach to enhance light collection and conversion using a scalable, straightforward, light-based additive manufacturing process.

The structure of the ear is one of the most important features of cereals associated with such agronomically important traits as productivity, resistance to environmental factors and pests, threshebility. Ears differ in shape, size, density, awnedness, color, etc. Analysis of the ear traits requires visual inspection, manual measurements and is very time-consuming. The effectiveness of ears’ phenotyping can be improved by the introduction of an automated image processing technology, storage of information in databases, use of machine learning algorithms to analyze this information. This paper presents a new approach for collecting, storing and analyzing of information about morphometric characteristics of ears of wheat. Two protocols for obtaining digital images of the ear have been developed. The computer-aided information system SpikeDroidDB has been developed, which allows you to store digital images of the ear, annotate their phenotypic features (14 features, including plant variety description, links to parent genotypes, generation, planting number, ear morphology description). The interface provides a flexible query system to access the data. SpikeDroidDB represents an interconnected representation between genotype, phenotype, location, and growing conditions. The web interface of SpikeDroidDB is available at http://spikedroid.biores . cytogen.ru/ and allows you to work with the system as with desktop computers or mobile devices. We used SpikeDroidDB for the digitization and annotation of a collection of ears of F 2 hybrids from crosses between the Australian cultivar of common wheat Triple Dirk and accession KU506 of Chinese wheat Triticum yunnanense. This experiment includes analysis of 104 plants, 230 spike images. The analysis of the variability of ears in form, length, and other traits allowed determination of the type of their genetic control: compactness is controlled by two recessive genes, awn type and hairi ness at the site of attachment of the spikelet to the axis is controlled by single dominant gene type, hairiness on the axis of the spike is controlled by two dominant genes.

The oxygen evolution reaction (OER) is an important reaction especially in water splitting and metal–air batteries. Highly efficient non-noble metal based electrocatalysts are urgently required to be developed and to replace the commercial Ru/Ir based oxide. Herein, we report the three-dimensional hierarchical NiCo2O4/CNT-150 composite with high activity for the OER that was synthesized via a hydrothermal reaction and subsequent annealing. Compared with CNTs, commercial RuO2 catalysts, NiCo2O4/CNT, NiCo2O4/CNT-250, and NiCo2O4/CNT-150 exhibit enhanced electrocatalytic performance with a lower onset overpotential of 300 mV and the corresponding Tafel slope of 129 mV per decade. The flower-like NiCo2O4/CNT-150 shows an excellent catalysis performance with higher current density than the commercial RuO2 catalyst. Moreover, the NiCo2O4/CNT-150 demonstrates the excellent long-term durability in 0.1 mol L−1 KOH for the OER. The significant catalytic performances are ascribed to the excellent conductivity of CNTs and the high specific surface area of the three dimensional flower-like NiCo2O4.

Considering that hyperaccumulators can accumulate high concentrations of iron salt, they can successfully obtain magnetic hydrochar from iron-rich hyperaccumulators. In this study, iron-rich biomass was obtained by irrigating Phytolacca acinosa Roxb. using iron salt. Magnetic nano-Fe3O4 hydrochar was prepared from iron-rich Phytolacca acinosa Roxb. via hydrothermal carbonization to remove Cd. The characterization results showed that the synthesized magnetic nanoparticles had an average size of 2.62 ± 0.56 nm and N elements were doped into magnetic nano-Fe3O4 hydrochar with abundant oxygenic groups. Cd adsorption on magnetic nano-Fe3O4 hydrochar was better fitted using the Langmuir isotherm and the pseudo-second-order kinetic model. The maximum adsorption capacity was 246.6 mg g−1 of Cd. The research confirmed that Cd adsorption was controlled by multiple mechanisms from the jar test, transmission electron microscopy mapping, scanning electron microscopy-energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. CdCO3 crystals can be formed after adsorption, indicating that surface precipitation played an important role in Cd adsorption. The abundance of O atoms and the doping of N atoms on the hydrochar surface were conducive to Cd adsorption, indicating that the mechanisms were related to surface complexation and electrostatic attraction. In addition, the significant decrease in Na+ content after Cd adsorption illustrated that ion exchange had a non-negligible effect on Cd adsorption. This study not only provides a strategy for preparing magnetic nano-Fe3O4 hydrochar derived from iron-rich plants but also verifies multiple Cd adsorption mechanisms using magnetic nano-Fe3O4 hydrochar.

We report a study on the growth kinetics and resultant structures of arrays of pillars in photo-cross-linkable films during irradiation with a periodic array of microscale optical beams under ambient conditions. The optical beams experience a self-focusing nonlinearity owing to the photopolymerization-induced changes in refractive index, thereby concentrating light and driving the concurrent, parallel growth of microscale pillars along their path length. We demonstrate control over the pillar spacing and pillar height with the irradiation intensity, film thickness, and the size and spacing of the optical beams. The growth of individual pillars in a periodic array arises from the combination of intense irradiation in the beam regions and oxygen inhibition afforded by the open, ambient conditions under which growth is carried out. We propose a kinetic model for pillar growth that includes free-radical generation and oxygen inhibition in thick films of photoinitiated media in order to interpret the experimen...

This paper presents geochronological, mineralogical, geochemical, and Sr-Nd isotopic data for recently identified Upper Triassic appinite dyke swarms in the East Kunlun orogenic belt (EKOB), northern Tibetan Plateau. Zircon U-Pb isotopic analyses using SHRIMP and LA-ICP-MS techniques yield 206 Pb/ 238 U ages of 226.1 ± 1.9 Ma and 226.4 ± 3.5 Ma, which can be interpreted as the crystallization ages of the appinite dykes. All the samples are characterized by high Al 2 O 3 contents, enrichments in light rare earth elements (LREEs) and large ion lithophile elements (LILEs) and strong depletions in Nb, Ta, Ti and P. These characteristics are comparable to those of subduction-related calc-alkaline high-Al basalts. Delayed plagioclase nucleation caused by relatively high-pressure conditions and high H 2 O contents is the most likely interpretation of the high Al contents. The geochemical and isotopic variations suggest that the appinite dykes were derived from partial melting of a mixed mantle source consisting of enriched lithospheric mantle and MORB-type asthenospheric mantle and had experienced some degree of crustal contamination during migration through continental crust. The appinite dykes are associated with previously documented, contemporaneous high-Ba-Sr and/or high-Sr/Y granites (225–223 Ma) derived from thickened mafic lower crust. These rocks provide important constraints on the compositional variations in the orogenic lithospheric mantle during the Late Triassic and provide evidence of a post-collisional environment associated with lithospheric delamination or slab break-off.

Advances in genome sequencing and assembly technologies are generating many high quality genome sequences, but assemblies of large, repeat-rich polyploid genomes, such as that of bread wheat, remain fragmented and incomplete. We have generated a new wheat whole-genome shotgun sequence assembly using a combination of optimised data types and an assembly algorithm designed to deal with large and complex genomes. The new assembly represents more than 78% of the genome with a scaffold N50 of 88.8kbp that has a high fidelity to the input data. Our new annotation combines strand-specific Illumina RNAseq and PacBio full-length cDNAs to identify 104,091 high confidence protein-coding genes and 10,156 non-coding RNA genes. We confirmed three known and identified one novel genome rearrangements. Our approach enables the rapid and scalable assembly of wheat genomes, the identification of structural variants, and the definition of complete gene models, all powerful resources for trait analysis and breeding of this key global crop. [Supplemental material is available for this article.]

In this paper, high-efficiency low-filling-factor sheet beam extended interaction oscillator (SB-EIO) with an improved ladder structure is discussed. The Ka-band cavity with nine gaps is designed to operate at $2\pi $ mode. A sheet beam (8 mm $\times $ 0.6 mm) of 34 kV and 3.5 A is injected into SB-EIO through a beam tunnel of $12~\text {mm}\times 1.2$ mm. The axial electric field distribution and the synchronization conditions are optimized to improve the beam-wave interaction efficiency. An effective method is explored and utilized to suppress the mode competition. A stable output power of 35.9 kW and 30% efficiency are obtained for a 0.56 filling factor in narrow direction and 0.67 filling factor in wide direction. An output power of 22.8 kW and 19.1% efficiency are also attained even with a 0.4 filling factor in narrow direction and 0.67 filling factor in wide direction.

Ultra sensitive detection of mercuric ion (Hg2+) with superior anti-interference capability from natural water is of great significance for food safety, environmental protection, and human health. We herein develop Au ordered nanorod arrays (Au NRAs) as surface-enhanced Raman scattering (SERS) substrates to construct SERS-active and signal-reproducible sensing platforms modified with 4-mercaptophenylboronic acid (4-MBA) as multifunctional SERS reporters. The aqueous Hg2+ can be efficiently trapped by 4-MBA through electrophilic substitution reactions and precisely appraise its concentration based on the collective spectral changes of reporters including peak disappearance, emergence, and Raman shift. Based on this, the optical nanoprobe shows an ultrahigh detection sensitivity of 0.1 nM for Hg2+, which is two orders of magnitude lower than the U.S.A. environmental protection agency (EPA)-required maximum level of drinkable water. It also offers both an exceptional Hg2+ discrimination against other metal ions as well as organic ligands and perfect feasibilities of detecting solutions with ultra-wide pH ranges from 1.0-14.0 at varying temperatures. Moreover, the nanoprobe demonstrates an ability to identify different chemical forms of mercury and has a high repeatability, accuracy and reliability to meet the practical detection requirements in natural environments.

Although numerous Paleo-Tethyan ophiolites with mid-oceanic ridge basalts (MORB) and/or oceanic-island basalt (OIB) affinities have been reported in the central Tibetan Plateau (CTP), the origin and tectonic nature of these ophiolites are not well understood. The petrogenesis, mantle sources and geodynamic setting of the mafic rocks from these ophiolites are unclear, which is the main reason for this uncertainty. In this paper, we present new geochronological, mineralogical and Sr-Nd isotopic data for the Chayong and Xiewu mafic complexes in the western Garze-Litang suture zone (GLS), a typical Paleo-Tethyan suture crossing the CTP. Zircon LA-ICP-MS U–Pb ages of 234 ± 3 Ma and 236 ± 2 Ma can be interpreted as formation times of the Chayong and Xiewu mafic complexes, respectively. The basalts and gabbros of the Chayong complex exhibit enriched MORB (E-MORB) compositional affinities except for a weak depletion of Nb, Ta and Ti relative to the primitive mantle, whereas the basalts and gabbros of the Xiewu complex display distinct E-MORB and OIB affinities. The geochemical features suggest a probable fractionation of olivine ± clinopyroxene ± plagioclase as well as insignificant crustal contamination. The geochemical and Sr-Nd isotopic data reveal that the Chayong mafic rocks may have been derived from depleted MORB-type mantle metasomatized by crustal components and Xiewu mafic rocks from enriched lithospheric mantle metasomatized by OIB-like components. The ratios of Zn/Fe t , La/Yb and Sm/Yb indicate that these mafic melts were produced by the partial melting of garnet + minor spinel-bearing peridotite or spinel ± minor garnet-bearing peridotite. We propose that back-arc basin spreading associated with OIB/seamount recycling had occurred in the western GLS at least since the Middle Triassic times, and the decompression melting of the depleted MORB-type asthenosphere mantle and partial melting of sub-continental lithosphere were metasomatized by plume-related melts, such as OIB s, which led to the generation of the Chayong and Xiewu mafic melts.

We report on the fabrication of an open cellular solid structure using visible light photocuring in combination with light-induced self-writing. A visible light sensitive photopolymer is irradiated with multiple arrays of microscale optical beams, which are generated from LEDs. These beams undergo self-trapping and elicit the inscription of microscale, solid struts into the medium. This process creates a structure consisting of multiple, intersecting struts that form a microtruss structure. Such structures retain their elasticity at higher temperatures as compared to a bulk film of the same thickness. This is the first demonstration of visible light photocuring of photopolymers into a microtruss structure, as well as investigation into their elastic properties under tension. Keywords: Polymers, Self-trapping, Microstructures, Cellular solids

Special thermal conductivity bridging is conducted between metal matrix and graphene oxide (GO) with covalent bond (Cu-O-Si-O-C) from γ-glycidylether propyl trimethylsilane (GPTS) to decrease thermal resistance and weaken phonon scattering through interface. The implementation of this bridging process involves a pulsed electrophoretic deposition, in which the GPTS modified GO as thermal conductivity reinforcing material was deposited onto the Cu-Zn alloy. The composite morphology and interfacial structure by field emission environment scanning electron microscope shows that the GPTS-GO is uniformly deposited on the substrate surface, and there is no interlayer of the GPTS-GO/Cu differing from the GO/Cu without GPTS. Raman spectrum reveals the bonding of Cu-O-Si and Si-O-C to prove the bridging role of GPTS by structural defects of the graphene and the changes of relative characteristic peaks before and after modification, as well as the Fourier transform infrared spectrum results confirming the Cu-O-Si-O-C covalent bonds. Compared to the thermal stability and thermal conductivity by thermogravimetric analyzer from room temperature to a higher temperature of 150 °C for the GO/Cu sample without GPTS, the GPTS-GO/Cu exhibits significantly improved performances. The thermal conductivity achieves 415.2 and 361.9 W/mK at 50 °C to 150 °C, which is 5.01% and 6.00% higher than that of the GO/Cu, The thermal diffusion coefficient achieves 1.236 and 1.087 cm2/s at 50 °C to 150 °C, respectively.

The phase components in the xBaO·CaO·2Al 2 O 3 (where x varies from 5.0 to 6.0) system were investigated by using of the X-ray diffraction. The results illustrate that 5B·C·2A and 6B·C·2A compounds synthesized by co-precipitation are of single-phase with B5CA and B3CA structure after sintering at 1200 °С, respectively. Based on the Current-Voltage characteristics tests, the divergent current density J div is 7.2 A·cm−2 occurring at 1100 °С for the impregnated cathode with 6B·C·2A aluminate.

Silicon solar cells are the most widely deployed modules owing to their low-cost manufacture, large market, and suitable efficiencies for residential and commercial use. Methods to increase their solar energy collection must be easily integrated into module fabrication. We perform a theoretical and experimental study on the light collection properties of an encapsulant that incorporates a periodic array of air prisms, which overlay the metallic front contacts of silicon solar cells. We show that the light collection efficiency induced by the encapsulant depends on both the shape of the prisms and angle of incidence of incoming light. We elucidate the changes in collection efficiency in terms of the ray paths and reflection mechanisms in the encapsulant. We fabricated the encapsulant from a commercial silicone and studied the change in the external quantum efficiency (EQE) on an encapsulated, standard silicon solar cell. We observe efficiency enhancements, as compared to a uniform encapsulant, over the visible to near infrared region for a range of incident angles. This work demonstrates exactly how a periodic air prism architecture increases light collection, and how it may be designed to maximize light collection over the widest range of incident angles.

The characteristic shapes and sizes of organs are established by cell proliferation patterns and final cell sizes, but the underlying molecular mechanisms coordinating these are poorly understood. Here we characterize a ubiquitin-activated peptidase called DA1 that limits the duration of cell proliferation during organ growth in Arabidopsis thaliana. The peptidase is activated by two RING E3 ligases, Big Brother (BB) and DA2, which are subsequently cleaved by the activated peptidase and destabilized. In the case of BB, cleavage leads to destabilization by the RING E3 ligase PROTEOLYSIS 1 (PRT1) of the N-end rule pathway. DA1 peptidase activity also cleaves the deubiquitylase UBP15, which promotes cell proliferation, and the transcription factors TEOSINTE BRANCED 1/CYCLOIDEA/PCF 15 (TCP15) and TCP22, which promote cell proliferation and repress endoreduplication. We propose that DA1 peptidase activity regulates the duration of cell proliferation and the transition to endoreduplication and differentiation during organ formation in plants by coordinating the destabilization of regulatory proteins.

基于Ag包覆聚苯乙烯球（PS@Ag）纳米探针和Ag覆盖硅金字塔结构（Si@Ag）阵列基底构建“三明治”免疫结构，开展表面增强拉曼散射（SERS）特性研究，实现了肝癌肿瘤标志物甲胎蛋白（AFP）的高灵敏、高特异性的检测.通过硝酸银原位还原生成PS@Ag纳米粒子，再依次链接4-巯基苯甲酸（4-MBA）及甲胎蛋白抗体（Anti-AFP）制备得到PS@Ag免疫探针.采用Langmiur-Bloggt膜技术、等离子体刻蚀和湿法刻蚀技术，以PS球阵列为模版，刻蚀大面积硅金字塔结构，再依次沉积Ag膜和链接Anti-AFP制备得到免疫基底.结果表明，基于“三明治”免疫结构的SERS检测方案具有高灵敏度（检测极限为1.75 fg·mL-1）和宽的动态范围（2 fg·mL-1~200 ng·mL-1）.此外，对临床人体血清样品进行SERS免疫检测，得到了与化学免疫发光法一致的结果，而且具有更高的灵敏度，可应用于肝癌的早期检测与诊断.

The fabrication of a new type of solar cell encapsulation architecture comprising a periodic array of step-index waveguides is reported. The materials are fabricated through patterning with light in a photoreactive binary blend of crosslinking acrylate and urethane, wherein phase separation induces the spontaneous, directed formation of broadband, cylindrical waveguides. This microstructured material efficiently collects and transmits optical energy over a wide range of entry angles. Silicon solar cells comprising this encapsulation architecture show greater total external quantum efficiencies and enhanced wide-angle light capture and conversion. This is a rapid, straightforward, and scalable approach to process light-collecting structures, whereby significant increases in cell performance may be achieved.

The masses of supermassive black holes at the centres of local galaxies appear to be tightly correlated with the mass and velocity dispersions of their galactic hosts. However, the local Mbh–Mstar relation inferred from dynamically measured inactive black holes is up to an order-of-magnitude higher than some estimates from active black holes, and recent work suggests that this discrepancy arises from selection bias on the sample of dynamical black hole mass measurements. In this work, we combine X-ray measurements of the mean black hole accretion luminosity as a function of stellar mass and redshift with empirical models of galaxy stellar mass growth, integrating over time to predict the evolving Mbh–Mstar relation. The implied relation is nearly independent of redshift, indicating that stellar and black hole masses grow, on average, at similar rates. Matching the de-biased local Mbh–Mstar relation requires a mean radiative efficiency ε ≳ 0.15, in line with theoretical expectations for accretion on to spinning black holes. However, matching the ‘raw’ observed relation for inactive black holes requires ε ∼ 0.02, far below theoretical expectations. This result provides independent evidence for selection bias in dynamically estimated black hole masses, a conclusion that is robust to uncertainties in bolometric corrections, obscured active black hole fractions, and kinetic accretion efficiency. For our fiducial assumptions, they favour moderate-to-rapid spins of typical supermassive black holes, to achieve ε ∼ 0.12–0.20. Our approach has similarities to the classic Soltan analysis, but by using galaxy-based data instead of integrated quantities we are able to focus on regimes where observational uncertainties are minimized., FS acknowledges partial support from a Leverhulme Trust Research Fellowship. RC acknowledges financial support from CONICYT Doctorado Nacional N° 21161487 and CONICYT PIA ACT172033. DMA thanks the Science and Technology Facilities Council (STFC) for support from grant no. ST/L00075X/1. ID is supported by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 788679. MM acknowledges support from the Beatriu de Pinos fellowship (2017-BP-00114).