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High-energy exciton emission could allow single-component multi-colour display or white light-emitting diodes. However, the thermal relaxation of high-energy excitons is much faster than the photon emission of them, making them non-emissive. Here, we report quantum dots with light hole-heavy hole splitting exhibiting strong high-energy exciton electroluminescence from high-lying light holes, opening a gate for high-performance multi-colour light sources. The high-energy electroluminescence can reach 44.5% of the band-edge heavy-hole exciton emission at an electron flux density Φe of 0.71 × 1019 s−1 cm−2 − 600 times lower than the photon flux density Φp (4.3 × 1021 s−1 cm−2) required for the similar ratio. Our simulation and experimental results suggest that the oscillator strength of heavy holes reduces more than that of light holes under electric fields. We attribute this as the main reason for strong light-hole electroluminescence. We observe this phenomenon in both CdxZn1-xSe-ZnS and CdSe-CdS core-shell quantum dots exhibiting large light hole-heavy hole splittings. Previous observations of high-energy exciton electroluminescence rely on filling the ground state with excessive charges, Wang et al. report such observation from quantum dots at low charge concentration by increasing the relative oscillator strength of higher-lying light holes comparing to that of ground-state heavy holes. [ABSTRACT FROM AUTHOR]

Middle Permian Qixia Formation in the southwestern region of Sichuan (SW China) has experienced multiphase fluidisation, resulting in an unclear understanding of the reservoir reconstruction effect. In this study, a systematic analysis of the Qi2 member in Wulong Town was carried out by combining field outcrop petrology and geochemistry. The results demonstrated that multiple sets of crystalline dolomite-bioclastic limestone cycles were stacked vertically in the Qi2 member, accompanied by the development of fractures and karst channels. The dolomite was mainly composed of silty-fine dolomite (D1) and recrystallised dolomite (D2). Furthermore, obvious multiphase dolomitic cements (Cd1-Cd2) were present in the fractures and pores. Early karst is known to have lithologic mutation surface development and karst channel development at the top of several secondary cycles. The vadose silt dolomites (Cd1) having karst channels developed dull luminescence under cathode luminescence (CL). Both the geochemical indicators of elements and rare earth element (REE) content indicated dysoxic-oxic environmental conditions. The hydrothermal solution displayed tectonic carniole characteristics in the strata burial stage. Fractures and pores were filled with hydrothermal minerals such as coarse dolomites-saddle dolomites (Cd2, with some caused by recrystallisation of the Cd1 hydrothermal solution) and fluorites. Coarse dolomites-saddle dolomites developed dull-red luminescence with a bright-red rim under CL and their δ18OVPDB values were more negative than those of middle Permian limestone samples. Both the geochemical indicators of elements and REE content indicated the suboxic-anoxic environmental conditions. Karstification had minor constructive impact on the reservoir of the Qi2 member in Baoxing in southwestern Sichuan. Most products of karstification were distributed as fillings in channels. Aside from creating certain networked fractures, the hydrothermal solution was mainly filled with hydrothermal minerals along the fractures, pores and early karst channels. Karst and the hydrothermal solution mainly damaged the middle and upper parts of the middle Permian Qixia Formation in Southwest Sichuan. The impact of episodic fluid on the restoration of the carbonate reservoir was mainly restricted by channels for fluid migration and thickness differences among the reservoir. However, certain thick-layered and massive crystalline dolomite may hold promise for exploration. [ABSTRACT FROM AUTHOR]

Shear phonons are collective atomic-layer motions in layered materials that carry critical information about mechanical, thermal and optoelectronic properties. Phonon branches with co-directional atomic-layer motions carry unique information about the global structure and hidden interfaces in layered crystals and heterostructures, but they are not detectable due to the very limited electron–phonon coupling. Here we utilize the propagating feature and mechanical coupling between shear phonons and localized plasmonic cavities to successfully realize direct characterization of ground-state shear phonons down to 4 cm−1 in energy by introducing mechano-Raman spectroscopy (MRS). MRS has the ability to characterize the global crystal structure with more than 108-fold enhancement and to accurately measure subpicometre displacements under ambient conditions with a thermal-noise-free feature. The propagating behaviour and the capacity of MRS to detect optically hidden interfaces are demonstrated. The broad tunability of plasmons makes the MRS technique a robust tool for extensive applications, including global crystal flaw detection, mechanical sensing and the mechanical modulation of light. Mechano-Raman spectroscopy is demonstrated by using interlayer phonons of atomic-layer vibrators to drive synchronous motion of the metallic plasmonic structure that can then be detected. The modulated light scattering brings out the information that cannot be accessed by optical Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Running a reliable network on resource-limited platforms for a low-resolution image is a great challenge for heatmap-based human pose estimation (HPE). Scale mismatch between the input image and heatmaps and the intrinsic quantization effect induced by the 'argmax' function hinder the performance of heatmap-based human pose estimation for low-resolution image. In this paper, we propose a coordinate-decoupled and offset-revised module (CDORM) to tackle these challenges. The proposed CDORM uses two coordinate-decoupled 1-D heatmaps to supervise the regression process of determining the horizontal and vertical locations of human joints, and employs offset regressing to alleviate the effect of quantization. The CDORM can be integrated with any current heatmap-based HPE network without increasing the size of network significantly. Experimental results on the COCO and MPII datasets show that CDORM helps heatmap-based regression approaches obtain high estimation accuracy from the low-resolution image and only slightly increases the size and runtime of the network. [ABSTRACT FROM AUTHOR]

The study on dolomite characteristics and its forming mechanism is of great significance for dolomitization theory and dolomite reservoir exploration. In recent years, the exploration of dolomite reservoirs in the Sichuan Basin has reached a bottleneck state. This study takes the Qixia Formation, Middle Permian in Northwest Sichuan basin as an example, the characteristics, distribution, diagenetic fluid, diagenetic environment of dolomite, and the dolomite formation mechanism were analyzed by means of observation and sampling of outcrops and cores, electronic scanning microscopy (SEM), and measurements of rare-earth elements (REEs), carbon isotopes, oxygen isotopes, and strontium isotopes. The results show that the dolomite exists in two forms, P-dol (dolomite in the dolomitic part of the mottled dolomitic limestone), and C-dol (crystalline dolomite). Core photos show that C-dol can be divided into two types: dolomite-A (dol-A) and dolomite-B (dol-B). The samples are low ∑REEs + Y, 13C (1.32‰–4.32‰), negative δ18O (− 5.87‰ to − 1.99‰) and δCe, and high in δEu and 87Sr/86Sr ratio (0.70724–0.70923). The partition pattern of REEs in the samples shows seawater characteristics of LREE loss, La enrichment, Ce weak loss, and Gd enrichment. These characteristics indicate that the diagenetic fluid of dolomite in the study area was a hybrid of seawater and freshwater and the diagenetic environment was at relatively high temperature. Moreover, after extending the “Mg cage effect” theory proposed by Folk, it is found that Mg2+ removed from sediments that were flushed by fresh water during the syndiagenetic stage facilitate the formation of dolomites. In accordance with the geological setting, a unique dolomitization model of the Middle Permian Qixia formation in the northwestern Sichuan Basin was built. The stratum in this model can be divided into four zones from top to bottom: freshwater vadose zone, mixed vadose zone, mixed phreatic zone, and seawater phreatic zone. The mottled dolomitic limestone is developed in the mixed vadose zone and the crystalline dolomite in the mixed phreatic zone. This study provides important evidences for the formation mechanism of dolomite and a reference to the study of ancient dolomite genesis and reservoirs of the Middle Permian Qixia formation in the northwest Sichuan Basin. [ABSTRACT FROM AUTHOR]

Great breakthroughs have been recently made in exploring oil and gas in the Middle Permian Qixia Formation, the southwestern Sichuan Basin, China. These discoveries in dolomitic reservoirs revealed abundant hydrocarbon reserves, agreeing on traditional predictions associated with dolomite prospect, which also left the controversy about the nature of dolomitization. Therefore, it is particularly important to research dolomite reservoirs characteristics and their genesis. In this study, comprehensive analyses, including pore-casted thin-section observation, scanning electron microscopy, physical property analysis, mercury injection measurement, fluid inclusion test, and isotopic measurement, are carried out to characterize Qixia Formation dolomites that are sampled from five outcrop sections and nine wells, followed by an investigation into controlling factors of these characteristics and establishment of pore evolution models. Granular dolomites, especially fine-grained and coarser dolomites, are demonstrated to be the best reservoir rocks, with their reservoir capacity positively related to dolomite grain sizes. There are mainly four types of pore-throat structures, namely large pores with wide throats, medium pores with medium throats, small pores with narrow throats, and fracture pore-throat structure. Dolomite reservoirs in the study area have experienced complex diagenetic changes, including the meteoric water dissolution in the penecontemporaneous stage, dolomitization in the shallow-burial stage, and hydrothermal- and formation water-related dissolution during the middle-deep burial stage. High-quality reservoirs are mainly distributed in the shoal facies deposits, especially where both dolomitization and multi-stage dissolution have occurred. [ABSTRACT FROM AUTHOR]

As the new generation of information technology, blockchain is characterized by a set of unique qualities and features in data storage and computing infrastructure, such as data traceability, data security, decentralized consensus, and decentralized process execution. These characteristics make it to be an important enabling technology for smart manufacturing, especially in product lifecycle management (PLM). In this paper, key features of blockchain are summarized, and its development history is analyzed first. Then, the challenges of PLM in data management and data security among multi-stakeholders are investigated, and a potential way to address these challenges by employing blockchain is discussed. An assessment framework is designed to evaluate the viability of applying blockchain in specific PLM scenarios. The application or potential application of blockchain in each section of PLM is studied in detail. Finally, both technical and non-technical challenges of applying blockchain in PLM are pointed out to achieve more effective applications. [ABSTRACT FROM AUTHOR]

To identify water inrush sources quickly and effectively, six hydrated ions, namely, Na++ K+, Ca2+, Mg2+, Cl−, SO42−, and HCO3−, were selected as discriminant indices. Considering the unobvious and fuzzy boundaries of water quality between aquifers, Elman neural network (ENN) was chosen as the basis of the discrimination model; in order to overcome the error backpropagation algorithm of ENN, genetic algorithm (GA) was selected to optimize ENN through initialization, fitness evaluation, selection, crossover, and mutation, creating an improved discrimination model called GA-ENN. On the basis of giving consideration to the principle of fairness, GA-ENN was compared with ENN, backpropagation neural network (BPNN), and the BPNN optimized by GA (GA-BPNN). The results shows that GA-ENN outperformed the other three models in convergence speed and output accuracy and GA-ENN can reflect the dynamic changes of the water quality in the aquifer through years of mining. Apart from the hydrogeological conditions of the coalmine, representative and accurate hydration data should be selected to improve the accuracy and validity of source discrimination of mine water inrush. [ABSTRACT FROM AUTHOR]

To elaborate genesis of the Ordovician Ma55 Sub-member dolomites in the Ordos Basin, this study implemented a series of analyses, including petrological investigation and geochemical (constant and trace elements, and isotopes) characterization. Three main types of dolomites were identified, namely micritic dolomite, micritic silty dolomite and silty dolomite. Specifically, the micritic dolomite is featured by dull red luminescence, low degree of order, high Sr isotope value, positive linear MgO–CaO correlation, high contents of Na and Sr elements, low contents of Fe and Mn elements, obvious negative δ13C excursion and slightly positive δ18O value, all of which indicate a syngenetic–penesyngenetic closed, high salinity environment. In comparison, the micritic silty dolomite is characterized by no or extremely dull red luminescence, moderate-to-high degree of order, higher δ13C value, slightly lower 87Sr/86Sr ratio, and sharp decrease in contents of K, Al, Fe and Mn elements, all of which indicate this type of dolomite to be the product of seepage–reflux dolomitization. Moreover, difference in geochemical characteristics between micritic silty dolomites in the depression and those in the platform flat suggests the Mg-rich brine from the tidal flat to be the dolomitization fluid for the platform flat while the Mg-rich brine from the overlying Ma54 Sub-member to be the dolomitization fluid for the depression. Meanwhile, the silty dolomite is observed to have no or extremely dull red luminescence, high degree of order, heavy δ18O value, high Sr isotope, lower Na content, and higher Fe and Mn contents, which are attributed to burial dolomitization in the fresh water environment. The distribution of dolomite was demonstrated to be controlled by sedimentary microfacies, and the dolomite in the West Jingbian dolomitic flat area turns out to have the largest distribution area and thickness as well as the best reservoir capacity. Massive fractures and vugs were formed in the dolomitization process, which were the basis of high-quality reservoir formation, involving generation of a relatively small amount of intercrystalline micropores during the syngenetic–penesyngenetic dolomitization, intercrystalline pores after the penecontemporaneous dolomitization, and intercrystalline and dissolution pores during the burial dolomitization. Moreover, dissolution during hypergene and burial periods contributed to most of the reservoir space, while filling effect during the burial period significantly reduced porosity. [ABSTRACT FROM AUTHOR]

Cross-modal hashing has recently gained significant popularity to facilitate multimedia retrieval across different modalities. Since the acquisition of large-scale labeled training data are very labor intensive, most supervised cross-modal hashing methods are uncompetitive for real applications. With limited label available, this paper presents a novel S emi-S upervised D iscrete H ashing (SSDH) for efficient cross-modal retrieval. In contrast to most semi-supervised cross-modal hashing works that need to predict the label of unlabeled data, our proposed approach groups the labeled and unlabeled data together, and exploits the informative unlabeled data to promote hashing code learning directly. Specifically, the proposed SSDH approach utilizes the relaxed hash representations to characterize each modality, and learns the semi-supervised semantic-preserving regularization to correlate the semantic consistency between the heterogeneous modalities. Accordingly, an efficient objective function is proposed to learn the hash representation, while designing an efficient optimization algorithm to optimize the hash codes for both labeled and unlabeled data. Without sacrificing the retrieval performance, the proposed SSDH method is adaptive to benefit various kinds of retrieval tasks, i.e., unsupervised, semi-supervised and supervised. Experimental results compared with several competitive algorithms show the effectiveness of the proposed method and its superiority over state-of-the-arts. [ABSTRACT FROM AUTHOR]

Previous studies on graptolites have mainly focused on stratigraphic division and sedimentary environment analysis. On the basis of previous studies of Ordovician and Silurian graptolites in the Middle–Upper Yangtze region, this paper makes full use of core analysis, drilling geological, experimental analysis, and logging data from wells and combines graptolite types in different sedimentary environments to identify 4 graptolite zones, WF1–WF4, and 9 graptolite zones, LM1–LM9, in the Silurian Longmaxi Formation in the Middle–Upper Yangtze region, among which WF2–LM4 present high total organic carbon (TOC), organic pore development, and shale gas enrichment and are favorable development zones. This study reveals that enrichment in graptolites has positive correlations with TOC, organic porosity, and total hydrocarbon content. The evolution of graptolites has contributed to the enrichment in organic matter and the formation of organic pores in shales and affects shale gas–bearing properties to a certain extent, which is an important indicator for shale gas reservoir evaluation. [ABSTRACT FROM AUTHOR]

This paper takes the thick and widely distributed crystal dolomite of Xixiangchi Formation, Upper Cambrian in Southeastern Sichuan basin as an example, the reservoir characteristics and main controlling factors of crystal dolomite have been analyzed systematically, and the genesis and reservoir formation mechanism of crystal dolomite have been discussed. It shows that the main reservoir rocks of crystal dolomite include powder crystalline dolomite and finely crystalline dolomites, and the intercrystal pores and dissolved intercrystal pores are the main reservoir spaces, with few dissolved vugs and fractures developed in the reservoir. The pore structure analysis shows that the throats of crystal dolomite reservoir are mainly lamellar, reflecting a good configuration between pores and throats, medium- low porosity and low permeability, representing typical porous-type reservoir. Dolomitization analysis indicates that the dolomitization occurred in the penecontemporaneous or early diagenetic stage. The degree of dolomitization decreased gradually from the top to the bottom in each sedimentary cycle, and distribution of dolomite in the study area shows that the content of dolomites decreases from the west to the east, which reflects the degree of dolomitization weakening eastward. Combined with the geochemical research of crystal dolomite, the C and O isotope data reflect the same characteristics of seawater during the late Cambrian. It indicates that the dolomitization might be related to the seepage-reflux of seawater in the early time. Recrystallization played an important role in the genesis of the crystal dolomite, because most of crystal dolomites remain residual granular texture. The intercrystal pores formed by seepage–reflux dolomitization acted as superior seepage channels for the reservoir transformation, and the recrystallization adjusted the previous pores and made them better, while the karstification was the key to the dissolved pore formation. [ABSTRACT FROM AUTHOR]

As p-n heterojunction photocatalysts usually possess dramatically improved photocatalytic activity than single photocatalysts, a novel ZnO/Cu2O heterojunction was designed by a facile self-templating method in this study. The crystal structure, chemical composition, surface morphology, and optical property of ZnO/Cu2O heterojunction were investigated to clarify the structure-property correlation. Scanning electron microscope and transmission electron microscope images proved the uniform core-shell submicrospheres of ZnO/Cu2O, in which a three-dimensional flower-like ZnO core was coated by a shell comprised of Cu2O nanoparticles. The photoresponse result showed that the band gap of the ZnO/Cu2O core-shell submicrospheres became narrow, and the absorption edge shifted from the ultraviolet region (380 nm) to the visible region (500 nm) compared with the pure ZnO microflowers. For the degradation of Rhodamine B under visible light, the photocatalytic efficiency of ZnO/Cu2O submicrospheres reached 96% within 40 min of reaction time, which was 3.8 times higher than that of pure ZnO microflowers and up to 4.5 times than that for pure Cu2O nanoparticles. The remarkable visible light-driven photocatalytic performance is mainly attributed to the extended photoresponse range and effective separation of the photo-generated electron-hole pairs in the unique heterojunction.ZnO/Cu2O core-shell microspheres for the degradation of RhB under visible light A novel core-shell ZnO/Cu2O heterojunction was synthesized by a facile self-templating method.Core-shell ZnO/Cu2O submicrospheres were comprised of three-dimensional flowerlike ZnO core coated by a shell of Cu2O nanoparticles.The band gap of ZnO/Cu2O submicrospheres became narrow and the absorption edge shifted to the visible region.ZnO/Cu2O submicrospheres exhibited better visible light-driven photocatalytic performance than pure ZnO or Cu2O. [ABSTRACT FROM AUTHOR]

The Middle Triassic Leikoupo Formation in the northern Sichuan Basin is a new discovery sequence for strategy replacement in the gas exploration field. The carbonate paleokarst reservoirs of the Middle Triassic Leikoupo Formation in the northern Sichuan Basin provide a case study of gas exploration in carbonate paleokarst reservoirs. By conducting a comprehensive study of well drilling, drill cores, well loggings, and test data, combined with the analysis of geological background of the Sichuan Basin, it is considered that syndepositional, supergene, and burial paleokarstification can be identified in the Leikoupo Formation, and these types of karstification were vital for reservoirs formation. Syndepositional karstification controlled the formation and distribution of early reservoirs. This type of karstification was limited to high-energy grain shoals, and therefore its horizontal extent was limited by the distribution of this facies. During temporary episodes of relative sea level fall, carbonate shoals were exposed subaerially or within the fresh water lens, and significant selective dissolution occurs, forming moldic pores and intragranular dissolved pores. The reservoirs related to supergene karstification mainly occurred in the area of the buried hill containing carbonate rock at the top of the Leikoupo Formation, and are vertically limited within a depth of 70-90 m under the carbonate corrosion unconformity plane of the Leikoupo Formation. The reservoirs related to supergene karstification formed mainly in limestone breccia and vuggy limestone in surface karst zone, and the high-angle dissolved fracture and medium- and small-scale corrosion holes in vertical vadose zone, and medium and small corrosion holes, dissolved fractures, roof fracture-caves in horizontal karst zone. The karst monadnocks within karst slope are the most favorable microgeomorphic units for horizontal distribution of reservoirs. Burial karstification was related to dissolution of carbonate minerals by organic acids, and was the key factor in optimal transformation of reservoirs. Burial karstification corroded and expanded the pore system left after infilling of the earlier pore system, and mainly was to optimize the transformation the reservoir space redistribution of earlier pore system. The compact carbonate layers related to burial karstification only can be dissolved along the early cracks in the channel and formation cracked reservoirs, but development of this type of reservoir was limited. The reservoirs were influenced by syndepositional, supergene, and burial paleokarstification in the Leikoupo Formation, and carbonate paleokarst reservoirs were formed finally. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides (2D TMDs) possess a tunable excitonic light emission that is sensitive to external conditions such as electric field, strain, and chemical doping. In this work, we reveal the interactions between DNA nucleobases, i.e., adenine (A), guanine (G), cytosine (C), and thymine (T) and monolayer WS by investigating the changes in the photoluminescence (PL) emissions of the monolayer WS after coating with nucleobase solutions. We found that adenine and guanine exert a clear effect on the PL profile of the monolayer WS and cause different PL evolution trends. In contrast, cytosine and thymine have little effect on the PL behavior. To obtain information on the interactions between the DNA bases and WS, a series of measurements were conducted on adenine-coated WS monolayers, as a demonstration. The p-type doping of the WS monolayers on the introduction of adenine is clearly shown by both the evolution of the PL spectra and the electrical transport response. Our findings open the door for the development of label-free optical sensing approaches in which the detection signals arise from the tunable excitonic emission of the TMD itself rather than the fluorescence signals of label molecules. This dopant-selective optical response to the DNA nucleobases fills the gaps in previously reported optical biosensing methods and indicates a potential new strategy for DNA sequencing. [ABSTRACT FROM AUTHOR]

Longwangmiao Formation in Lower Cambrian is one of the key petroleum systems in Sichuan basin. The reservoir is well developed in the Longwangmiao Formation which was deposited in the restricted carbonate platform. It is indicated that the karstification occurred in the reservoir of Longwangmiao Formation during the Caledonian tectonic movement on the basis of seismology, petrology, sedimentology and geochemistry. Distinguishable markers of the paleo-karstification include: the lost strata and unconformable contact occurring between Middle-Upper Cambrian carbonates and Lower Permian Liangshan Formation; the occurrence of collapse breccias and fillings in caves and karrens; the evident difference between cave fill dolostones and matrix dolomite in the Sr/Ba ratio; and the log response of cavernous formations. The karstification lasted for a long time. According to the residual thickness between the top of Longwangmiao Formation and the bottom of the Permian, paleo-geomorphology during the Caledonian karstification had been recovered. In that time, Longwangmiao Formation was not directly exposed to the surface in central Sichuan basin; lots of meteoric fresh water flowed through faults and cracks from Gaotai Formation and a series of vertical dissolved caverns and karrens were formed. Meanwhile, due to the denudation window of Leshan-Longnvsi paleo-uplift lying in the west of the study area, meteoric fresh water flowed from the denudation window and the Longwangmiao Formation became a karstic confined aquifer. Under the pressure, diagenetic fluid migrated along the formation. Consequently, elongated dissolved pores and vugs formed and bedding karst reservoir developed in Longwangmiao Formation. The intensity of the karstification weakened with the distance from the paleo-uplift increasing, which indicates that the karstification was deeply influenced by the paleo-uplift. Finally, the supergene karstification model of Longwangmiao Formation has been established on the basis of the synthesis of the above-mentioned research results. [ABSTRACT FROM AUTHOR]

The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual grain texture, and dolarenite of which the arene is mainly composed of muddy to micritic dolomite with some crystalline grain directionally aligned. The trace element indicates that the dolomites of Longwangmiao Formation may be related to the high salinity of sea water. The oxygen isotope values of crystalline dolomite and dolarenite are both similar to that of the Early Cambrian marine dolomites, and the carbon isotope values of every kind of dolomites are completely overlapped with that of the seawater in Early Cambrian, indicating the dolomitization fluid is originated from the Early Cambrian sea water. The restricted marine biological communities and a small amount of gypsum pseudonodule seen in muddy to micritic dolomite indicate that the sea water in Early Cambrian was restricted and evaporated. However, the general lack of massive evaporite mineral and gypsum karst breccia indicates that the salinity of sea water during dolomitization was lower than the value of gypsum's precipitation. The Longwangmiao Formation consists of several high-frequency sedimentary cycles, indicating frequent sea level changes. This study indicates that massive dolomitiza-tion may also occur in underwater palaeohigh in carbonate platform through the reflux of penesaline sea water driven by a combination of high- and low-frequency sea-level changes. This kind of dolomiti-zation can explain the generation of massive dolomites in the absence of evaporite precipitation, and further indicates that replacement dolomites can be produced by sea water with a wide range of salinity (normal, penesaline to hypersaline). [ABSTRACT FROM AUTHOR]

The TiO nanotube arrays (TiO NTAs) prepared by re-oxidation were chosen as basement. The NTAs prepared through re-oxidation show smoother surface and more uniform tube mouth on large scale compared with the first as-grown one. We use successive ionic layer adsorption and reaction method to deposit quantum dots (ZnS and CdS) onto the sample successively. The findings reveal that two kinds of quantum dots (∼10 nm) distribute regularly and the nanotube mouth is open. From the UV-Vis absorption spectrum of samples, the red shift occurs after the sedimentation of the two quantum dots, which proves that the double modification can expand the absorption to 650 nm. Among all specimens, the sample produced by co-deposition has the highest speed of catalytic efficiency of 90.7% compared with bare TiO NTAs (52.9%) and just CdS QDs sensitized sample (65.8%). In the test of photocatalysis durability, the decay percentages of CdS/TiO NTAs and ZnS/CdS/TiO NTAs were 35.8 and 48.4%, respectively, which means that the ZnS passivation layer plays a crucial role in enhancing photocatalytic activities. [ABSTRACT FROM AUTHOR]

Sedimentary facies is an important factor influencing shale gas accumulation. It not only controlls hydrocarbon generation, but also affects reservoir characteristics and distribution. This paper discusses the Lower Silurian Longmaxi Formation in the south of the Sichuan Basin. Outcrop, core, drilling and logging data identify the sedimentary facies of the formation as continental shelf facies, which is divided into two subfacies: an inner shelf and an outer shelf subfacies. These two subfacies can be further divided into seven microfacies: muddy silty shallow shelf, calcareous silty shallow shelf, muddy limy shallow shelf, storm flow, muddy deep shelf, silty muddy deep shelf and contour current microfacies. Vertical and horizontal distribution of microfacies establishes a sedimentation model of the continental shelf facies. Combined with analization or calculation of geochemical, mineralogical, physical and gas-bearing properties of samples, sedimentary microfacies is evaluated using nine parameters: total organic carbon content, effective shale continuous thickness, vitrinite reflectance, kerogen type, mineral components, porosity, permeability, water saturation and gas content. The evaluation revealed that the most favorable facies for shale gas exploration and development are the muddy deep shelf and part of the silty muddy deep shelf microfacies, with TOC more than 2%, siliceous component over 50%, clay less than 30%, porosity more than 3%, water saturation lower than 40%, gas content greater than 2 m/t. These results provide a theoretical basis for deciston-making on the most promising areas for shale gas exploration in the Sichuan Basin and for marine shale gas exploration and development in South China. [ABSTRACT FROM AUTHOR]

Transient expression of foreign genes by Agrobacterium infiltration is a versatile technique that can be used as a rapid tool for functional protein production in plants. A reproducible protocol of large-scale production of foreign proteins via the novel plant transient expression system in Pisum sativum L. was established in our study. Non-detached plants from soil-independent culture were used as the target organ, and vacuum infiltrating mediated by Agrobacterium tumefaciens harboring green fluorescent protein (GFP) gene was performed. Step-by-step optimization was performed and showed that the quality of plant material as well as agro-infiltration conditions were the major factors influencing the gene expression. Monitoring the transient GFP expression daily, the highest expression level was achieved on the 8th day post-infiltration. Evidence of anti-acidic fibroblast growth factor-single chain variable fragment (anti-aFGF-scFv) gene expression in pea seedling was also achieved using agro-mediated vacuum infiltration system. Our work proves that the system is suitable for the largescale production of pharmaceutical proteins. The in planta infiltration system described here provides a powerful tool to explore easily gene expression in Pisum sativum L. avoiding tissue culture steps and the labor-intensive generation of transgenic plants. [ABSTRACT FROM AUTHOR]

Purpose: To compare the discriminative power of the index scores of EQ-5D-5L (5L) and EQ-5D-3L (3L) in diabetes patients in China. Methods: A consecutive sample of type 2 diabetes mellitus (T2DM) patients in the clinics self-completed the two versions of EQ-5D. The 3L index score was obtained from the Chinese 3L value set; the 5L index score was predicted from the 3L index score using an interim scoring. Relative efficiency (RE) of the 5L and 3L index scores was calculated to compare their ability in differentiating between T2DM patients with and without one of ten clinical conditions. The efficiency of the 5L and 3L health state classification systems was assessed using the Shannon index ( H′) and in terms of ceiling effects. Results: A total of 289 T2DM patients participated in this study. The 5L score was systematically lower than the 3L score for T2DM patients with and without a condition (range −0.36 to −0.06). The 5L score exhibited higher discriminative power in nine of ten conditions, with the mean RE value being 1.92. 5L had higher H′ values than 3L in all the five EQ-5D dimensions: mobility (1.14 vs. 0.70), self-care (0.44 vs. 0.33), usual activities (0.72 vs. 0.47), pain/discomfort (1.58 vs. 1.10), and anxiety/depression (1.03 vs. 0.67). The overall ceiling effects decreased from 56.7 % (3L) to 36.7 % (5L). Conclusion: The 5L index score is more discriminative than the 3L index score in T2DM patients and therefore is preferable for use in this population. [ABSTRACT FROM AUTHOR]

Myosin X (Myo10), an untraditional member of myosin superfamily, is characterized as an actin-based molecular motor, which plays a critical role in diverse cellular motile events. Previous research by our group has found that Myo10 influenced neuronal radial migration in developing neocortex, but the underlying mechanism is still largely unknown. In this study, we found that knockdown of endogenous Myo10 in a normal gonadotropin-releasing hormone (GnRH) neuronal cell line transfected with the large T antigen (NLT) induced the impairment of cell motility and orientation. In the wound healing assay, with the Golgi complex staining to display cell polarity, Myo10 knockdown cells were randomly oriented compared to the control. Furthermore, suppressing the expression of Myo10 decreased the ability of cell-matrix adhesion. N-cadherin, a calcium-dependent classical cell adhesion molecule, rescued the migration deficiency caused by Myo10 knockdown in cell aggregates and collagen gel assay. These results suggest that Myo10 is required for neurogenic cell migration through N-cadherin mediated cell adhesion. [ABSTRACT FROM AUTHOR]

It is indicated in this paper that the karstification occurred in Block 12 of Tahe oilfield during Early Hercynian stage on the basis of identification features obtained through the latest research on seismology, petrology, and geochemistry. Distinguishable markers of the paleo-karstification mainly include: the lost strata and unconformable contact occurring between Lower-Middle Ordovician carbonates and Lower Carboniferous Bachu Formation, the occurrence of collapse breccias and fillings in subsurface stream, the evident difference between cave-fill calcite and matrix carbonate in the Sr/Ba ratio, and the log response for cavernous formations. The paleo-geomorphology of Early Hercynian karstification can be divided into four units: karst highland, I- and II-level karst slope, and karst basin in Tahe area, and the Block 12 was basically located in II-level karst slope. Three karst cycles developed in the Block 12 according to Early Hercynian tectonism characterized by multiphase pulse-type uplift movement and three sets of cavernous formation formed. II- and III-level cavernous formations mainly developed in Block 12. The Early Hercynian karstification is distributed on the north area of the pinch-out line of Upper Ordovician Sangtamu Formation in the plane, and is vertically developed in the Lower-Middle Ordovician carbonates. The karstification is essentially controlled by the paleo-geomorphology and fault. Fissures and caves formed by the karstification are the keys to affecting reservoir quality. The evolution model of Early Hercynian karstification has been established on the basis of the synthesis of the above-mentioned research results. It can be divided into three stages: rapidly uplifting and denudation stage, three episodes of uplifting and karstification, and subsiding and reworking stage. [ABSTRACT FROM AUTHOR]

Houba oil sand in frontier Longmenshan Mountain is one of the most typically important unconventional resources. The basic reservoir characteristics of oil sand and the main factors affecting reservoir quality were examined in this article based on porosity, permeability, and mercury porosimetry measurements; thin section analyses; SEM observation; and X-ray diffraction analysis. This study shows that the oil-bearing sandstone reservoir is mainly medium−coarse-grained sublitharenite and litharenite. The main pore type is intergranular pores, including residual primary intergranular pores, dissolved intergranular pores, and dissolved intragranular pores; fractures are common in this study area. The quality of sandstone reservoir is of high porosity and high permeability with a high oil saturation of 89.84 %. It is indicated that the main controlling factors of the reservoir in the study area include deposition, diagenesis, and tectonism. Deposition laid a foundation to porosity evolution, and channel sand is the most favorable depositional facies for the reservoir. Diagenetic alterations are the keys to reservoir evolution; dissolution and chlorite coatings cementation play an effective role in the generation and preservation of pores. Compaction, carbonate cementation, and quartz overgrowth cause many damages to the reservoir porosity. Fractures caused by structural breakages can improve the reservoir permeability and they also can provide fluid migration pathways to the late corrosion, which formed a lot of corroded fissures as reservoir and percolation spaces. [ABSTRACT FROM AUTHOR]

Bacterium strain PJ3, isolated from wastewater and identified as Arthrobacter sp. bacterium based on its 16S rDNA gene, could use carbazole as the sole carbon, nitrogen and energy source. The genomic library of strain PJ3 was constructed and a positive clone JM109 (pUCW402) was screened out for the expression of dioxygenase by the ability to form yellow ring-fission product. A 2,3-dihydroxybiphenyl dioxygenase (23DHBD) gene of 933 bp was found in the 3360 bp exogenous fragment of pUCW402 by GenSCAN software and BLAST analysis. The phylogenetic analysis showed that 23DHBD from strain PJ3 formed a deep branch separate from a cluster containing most known 23DHBD in GenBank. Southern hybridization confirmed for the first time that the 23DHBD gene was from the genomic DNA of Arthrobacter sp. PJ3. In order to test the gene function, recombinant bacterium BL21 (pETW-8) was constructed to express 23DHBD. The expression level in BL21 (pETW-8) was highest compared with the recombinant bacteria JM1O9 (pUCW402) and strain PJ3. We observed that 23DHBD was not absolute specific. The enzyme activity was higher with 2,3-dihydroxybiphenyl as a substrate than with catechol. The substrate specificity assay suggested that 23DHBD was essential for cleavage of bicyclic aromatic compounds during the course of aromatic compound biodegradation in Arthrobactersp. strain PJ3. [ABSTRACT FROM AUTHOR]

The presence of actin in the nucleus as well as its functions in various nuclear processes has been made clear in the past few years. Actin is known to be a part of chromatin-remodeling complexes BAF, which are required for maximal ATPase activity of the Brg1 component of the BAF complex. Moreover, the essential roles of actin in transcription mediated by RNA polymerases I, II and Ill have been demonstrated recently. On the other hand, a myosin I isoform, which contains a unique NH2-terminal extension for nucleus localization, has been specifically localized in nucleus. As is well known, myosin I is an actin-binding protein and plays an important role in various cellular activities. Though actin and nuclear myosin I (NM I) have been implicated to play distinct roles in gene expression, there has been no evidence for the actin-myosin interaction that might be involved in gene transcription mediated by RNA polymerase II (RNAP II). Here we show evidence that both actin and NM I are associated with RNAP II in nucleus by using co-localization and co-IP assays, and they may act together on gene transcription. The antibodies against β-actin or NM I can block RNA synthesis in a eukaryotic in vitro transcription system with template DNA comprising the promoter and the coding region of human autocrine motility factor receptor (hAMFR) gene; the antibodies pre-adsorbed with purified actin and NM I have no effect in transcriptional inhibition, indicating that the inhibition of transcription by anti-actin and anti-NM I Is specific. These results suggest a direct involvement of actin-myosin complexes In regulating transcription. It also implicates that actin and NM I may co-exist in a same complex with RNAP II and the interaction of RNAP II with actin and NM I functions in the RNAP II-mediated transcription. [ABSTRACT FROM AUTHOR]

Hairy roots of maize were induced by infecting 15-d calli with Agrobacterium rhizogenes. The hairy roots cultured in hormone-free media showed the vigorous growth and typical hairy root features. The regenerated plants were produced from hairy roots in MS media supplemented with 1.6 mg/L ZT and 0.4 mg/L NAA. The PCR-Southern hybridization demonstrated that T-DNA had been integrated into the chromosome of regenerated plants. [ABSTRACT FROM AUTHOR]

Synapsis and chiasma formation have been analyzed at the ultrastructural level in trihaploid wheat with and without chromosome 5B by spreading of microsporocytes. The euhaploids were obtained by anther culture of euhexaploid or monosomic 5B Chinese Spring wheat or from the hexaploid Chinese winter wheat variety Kedong. All three types of euhaploid wheat were virtually achiasmatic. Analysis of 31 spread zygotene nuclei, covering the entire zygotene stage, revealed that synaptonemal complex formation primarily was initiated interstitially whereafter the formation proceeded in the telomeric regions. Pairing partner exchanges were frequent, most of the lateral components within the individual nucleus being combined into a single multiple association. As synapsis proceeded the number of pairing partner exchanges decreased and at late zygotene many associations involved only two or three lateral components. The mean degree of synapsis achieved in haploids of Chinese Spring amounted to 35-40% while in haploids from Kedong up to 90% of the complement was combined with synaptonemal complexes. Analysis of a nullisomic 5B haploid plant derived from Chinese Spring wheat revealed a 45-fold increase in the number of chiasmata per cell at metaphase I compared to euhaploids. The differences in number of chiasmata were correlated with a nearly twofold increase in the number of pairing partner exchanges per lateral component compared to that found in euhaploid wheat. The elimination of the synaptonemal complex during diplotene was monitored in 37 euhaploid nuclei ranging in stage from early diplotene to diakinesis. As in hexaploid wheat the degradation of the synaptonemal complexes started at a low number of sites, generating a number of segments. These were thereafter degraded from their ends until by diakinesis elimination was complete or almost so. [ABSTRACT FROM AUTHOR]

The present paper summarizes and discusses the results obtained from a series of ultrastructural investigations of the effect of chromosome 5B on chromosome pairing, and synaptonemal complex formation in wheat, T. aestivum cv. Chinese Spring. The material comprises hexaploid wheat nullisomic for chromosome 5B, monosomic for 5B, euploid wheat, wheat where chromosomes 5B have been replaced by one, two or three copies of an isochromosome for the long arm of chromosome 5B; trihaploid wheat with and without 5B and hybrids between Chinese Spring wheat and diploid rye with chromosome 5B, without 5B or carrying an isochromosome for the long arm of 5B. It is shown that nullisomy for chromosome 5B in hexaploid wheat results in a two-to threefold increase in the number of lateral components in multiple associations already from the beginning of zygotene and in trihaploid wheat and wheat-rye hybrids in a two-to threefold increase in the number of pairing partner exchanges per lateral component involved in synapsis. Only nullisomy for chromosome 5B and triisosomy for the long arm of chromosome 5B permit crossing over between the homoeologous chromosomes of wheat. It is inferred that the product of the Ph locus on chromosome 5B affects both synapsis and crossing over. As these timewise separated processes are assumed both to be initiated by heteroduplex formation, this might provide the common link in the action of the Ph gene. The results obtained with the genotypes containing different dosage of the Ph gene disprove both the hypothesis that Ph influences a premeiotic chromosome rearrangement (13, 14, 15) and the hypothesis (18, 82) that Ph controls the timing of crossing over with respect to the process of correction of multiple pairing associations. [ABSTRACT FROM AUTHOR]

The effect of chromosome 5B on chromosome pairing and chiasma formation in hybrids between allohexaploid wheat and diploid rye has been analyzed by ultrastructural investigations of synaptonemal complexes in spread silver stained microsporocytes of hybrids nullisomic for chromosome 5B, euploid hybrids and hybrids carrying an isochromosome for the long arm of chromosome 5B. At metaphase I, there were a mean number of 6.9 chiasmata per cell in the nullisomic 5B hybrids and 0.7 chiasmata per cell in the euploid hybrids, while the monoisosomic 5BL hybrids were virtually achiasmatic, with the exception of the isochromosomes where chiasmata formed regularly between the homologous/identical arms. Up to 40-50% of the complement paired with a synaptonemal complex in the three genotypes, giving rise to multiple associations often involving nearly all lateral components. In the nullisomic 5B hybrids the number of pairing partner exchanges per lateral component engaged in synapsis at zygotene was twice that found in the two other genotypes. It is concluded that nullisomy for chromosome 5B in wheat-rye hybrids results both in a lower stringency of synapsis and in permissiveness for crossing over between homoeologues. [ABSTRACT FROM AUTHOR]

In this Article, the equation following the sentence "The extra damping introduced can be written as:" was incorrect and should have appeared as shown in the correction notice. [ABSTRACT FROM AUTHOR]

This corrects the article DOI: 10.1038/srep24105 [ABSTRACT FROM AUTHOR]

Grain shoals in the Lower Cambrian Longwangmiao Formation of southern Sichuan Basin were analyzed in terms of their characteristics, distribution, and major controlling factors, based on a combination of drilling, testing, logging, core, and thin section data. It is suggested that there should be two main types of rocks in the grain shoals: (1) granular dolomites (limestones) with remarkable granular structures formed mainly by psammitic or oolitic clastic and (2) crystalline dolomites with residual granular structures. Grain shoals in the study area were mainly unexposed shallow shoals with either upward-deepening or upward-shallowing structures vertically. Those grain shoals in the Weiyuan-Ziyang and Gaoshiti-Hechuan areas with the paleo-uplift in the northern part of the study area were featured by good stability and continuity in both scale and horizon, while those outside these areas were mainly patch shoals in small scales. Development characteristics and superimposition patterns of Longwangmiao Formation grain shoals were found to be controlled by changes of sea level and depositional energy, while their differential distribution were thought to be determined by paleogeomorphology during depositional stage. [ABSTRACT FROM AUTHOR]

We aimed to assess the association of cognitive dysfunction with health-related quality of life (HRQOL) among older adults in China. We analyzed community-based cross-sectional data of 5,557 Chinese individuals aged 60 years and above in the Weitang Geriatric Diseases Study. Cognitive dysfunction and HRQOL were assessed using the Abbreviated Mental Test (AMT) and the European Quality of Life-5 dimensions (EQ-5D), respectively. We estimated the impacts of cognitive dysfunction on the EQ-5D index and visual analogue scale (VAS) scores using linear regression models, and the association between cognitive dysfunction and self-reported EQ-5D health problems using logistic regression models. The EQ-5D index and VAS scores were significantly lower for individuals with cognitive dysfunction than their counterparts. After controlling for covariates, the differences in EQ-5D index and VAS scores between individuals with and without cognitive dysfunction were −0.016 (95% confidence interval [CI]: −0.024, −0.008), and −3.4 (95% CI: −4.5, −2.4), respectively. Cognitive dysfunction was associated with reporting of problems in pain/discomfort (odds ration [OR]: 1.37; 95% CI: 1.12, 1.69), and anxiety/depression (OR: 2.13; 95% CI: 1.41, 3.23). The negative impact on HRQOL increased with the severity of cognitive dysfunction. The results indicate cognitive dysfunction was associated with worse HRQOL in older adults. [ABSTRACT FROM AUTHOR]

A seedless hydrothermal method is developed to grow high density and vertically aligned ZnO micro/nanowire arrays with low defect density on metal films under the saturated nutrition solution. In particular, the mechanism of seedless method is discussed here. A buffer layer can be confirmed by transmission electron microscopy (TEM), which may release the elastic strain between ZnO and substrate to achieve this highly mismatched heteroepitaxial structures. Based on ZnO micro/nanowire arrays with excellent wettability surface, we prepared ZnO-FeS2-CuI p-i-n photodiode by all-solution processed method with the high rectifying ratio of 197 at ±1 V. Under AM 1.5 condition, the Jsc of 0.5 mA/cm2, on-off current ratio of 371 and fast photoresponse at zero bias voltage were obtained. This good performance comes from excellent collection ability of photogenerated electrons and holes due to the increased depletion layer width for p-i-n structure. Finally, the high responsivity around 900 nm shows the potential as near infrared photodetectors applications. [ABSTRACT FROM AUTHOR]