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The Wufeng Formation–Longmaxi Formation in the Sichuan Basin in South China is the key stratum for shale gas exploration and production. To date, three national shale gas demonstration zones have been developed. Nevertheless, there are still some test wells that have not yet been commercialized. In this study, the geological characteristics of commercial and non-commercial zones are analyzed, as are the main controlling factors of high-producing wells (high estimated ultimate recovery; EUR), and the reasons for low-production wells (low EUR) by dissecting the three national shale gas demonstration zones and the main shale gas exploration wells. The results of this study indicate the following: (1) The black shale in the WF2–LM4 graptolite zone is deposited in the Craton depression on the Upper Yangtze plate, which provides a relatively stable tectonic environment for tectonic deformation and uplift destruction. The large shale thickness and weak tectonic activity jointly result in shale gas being enriched mainly in the deep-water shelf. (2)The regional fault has a destructive effect on shale gas preservation, and the shale gas reservoir is likely to be destroyed. In the areas close to the regional fault, multiple fracture-fluid migration activities caused by multistage tectonic movements are also detrimental to shale gas preservation. Conversely, shale gas is generally well preserved in areas far from regional faults. (3) The black shale thickness in the WF2–LM4 graptolite zone in the deep-water shelf area controls the shale gas field distribution. Furthermore, the horizontal well trajectory in the WF2–LM4 graptolite zone determines the shale gas well test production and EUR. The results of this work will provide a reference for shale gas exploration and development of the Wufeng Formation–Longmaxi Formation in the Sichuan Basin, as well as the Silurian strata in other parts of the world.

T-junction structures play an important role in nuclear power plant systems. Research on liquid entrainment is mostly based on small-scale branch pipes (d/D ≤ 0.2) and attention paid to large-scale branch pipes (0.33

Derivation of mature red blood cells (RBCs) from stem cells in vitro is a promising solution to the current shortage of blood supply, in which terminal enucleation is the rate-limiting step. Here we discovered two cinnamamides B8 and B16 showed potential activities of enhancing the enucleation of erythroblasts through the screening of "in-house" compound library. Subsequently, twenty-four N-arylcinnamamides were rationally designed and synthesized on the basis of the structure of B8 and B16, in which N-(9H-carbazol-2-yl)cinnamamide (KS-2) significantly elevated the percentage of reticulocytes in the cultured mouse fetal liver cells in vitro (relative enucleation = 2.43). The underlying mechanism of KS-2 in promoting mouse erythroid enucleation is accelerating the process of cell cycle exit via p53 activation in late stage erythrocytes. These results strongly suggest that compound KS-2 is worthy of further study as a potential erythrocyte enucleation inducer.

The effects of plant hormones on plant growth of Zizania latifolia are still considered to be the difficult and hot spots. The present study was carried out to investigate the regulation mechanism of exogenous indole-3-acetic acid (IAA) and IAA transport inhibitor (2,3,5-triiodobenzoic acid, TIBA) on yield, photosynthesis capacity, carbon assimilation and interaction of plant-fugal of Ustilago esculenta Henn. These results displayed that exogenous IAA led to significant increases in gall growth rate, swollen gall volume and biomass accumulation, promoting yield per unit of swollen gall in Z. latifolia. Exogenous IAA could improve the net photosynthetic rate (Pn), which contributed to higher stomatal conductance (Gs) and transpiration rate (Tr) in plant. TIBA treatment markedly inhibited the plant growth and photosynthetic rate. Contents of sucrose, glucose, fructose and total soluble sugar by IAA were significantly higher than control, whereas these parameters were declined by TIBA. Exogenous TIBA resulted in accumulation of starch (unfavorable to sugar metabolism) and crude fiber contents (declined swollen gall quality). Additionally, it was firstly reported the stimulation of exogenously applied of IAA and TIBA on plant growth and hyphae growth of U. esculenta. Microscopic analyses revealed that abundant hyphae were well-distributed closely to cell wall after IAA treatment, which could produce endogenous plant hormones, promoting the swollen cell structure enlargement. And hyphal aggregation over-growth by TIBA treatment indicated the vigorously increase of hyphae was surpassed the plant self-growth. These changes were greatly contributed to the increase of endogenous IAA content. The utilization of exogenous IAA and TIBA in present study proved IAA played a dominant role in regulating Z. latifolia growth.

Existing information on insect compound eyes is mainly limited to two-dimensional information derived from histological or ultrathin sections. These allow a basic description of eye morphology, but are limited in z-axis resolution because of the section thickness or intervals between sections, so that accurate volumetric information cannot be generated. Here we use serial-sectioning transmission electron microscopy to present a 3-D reconstruction at ultrastructural level of a complete ommatidium of a miniaturized insect compound eye. Besides the general presentation of the three dimensional arrangement of the different cell types within the ommatidium, the reconstruction allowed volumetric measurements and numerical analyses to be undertaken, revealing new insights into the number, size and distribution of cell organelles in insect ommatidia. Morphological features that can be related to miniaturization, namely the dimensions and displacement of nuclei, reduction of average pigment granule volume and loss of pigment granules in the terminals of the cone cells, the impact of metabolic activity of cell types on miniaturization, as well as maintenance of rhabdomere volume and limits to its miniaturization, are all discussed.

It is a hot topic to seek cheap and efficient cocatalyst to improve the activity of graphitic carbon nitride (g-C3N4) in photocatalytic water splitting to produce hydrogen and photoelectrochemical (PEC) performance. Herein, we prepared successfully the novel 0D/2D heterojunction by the modification of Ni2P quantum dots (QDs) as cocatalyst on the surface of ultrathin g-C3N4 layer, which can greatly enhance the photocatalytic hydrogen production and PEC performance under visible light owing to the improvement of separation efficiency of photogenerated charge carriers and visible-light absorption capacity. Surprisingly, the optimum amount of Ni2P loaded on the g-C3N4 is 3 wt%, whose hydrogen production rate is 1503 μmol h−1 g−1 being far superior to that of g-C3N4 decorated by 3 wt% Pt (560 μmol h−1 g−1). Moreover, the photocurrent response value of Ni2P/g-C3N4 photocatalyst is over 11 times and 3 times that of pure g-C3N4 and Pt/g-C3N4, respectively. What’s better, the stable photocatalytic H2 evolution and PEC performance of Ni2P/g-C3N4 demonstrates its high stability and reusability resulting from Ni-N coordination on the surface of g-C3N4. This work provides valid evidence for the development of cheap, efficient and durable cocatalyst actting on the g-C3N4, opening up new opportunities and possibilities for dual function application.

Many theoretical and experimental studies have been conducted over the years on liquid entrainment through a branch pipe connected to the main horizontal pipe (i.e., entrainment at the T-junction). Several mathematical models have been developed to predict the onset of liquid entrainment and branch quality during the liquid entrainment process with reasonable accuracy. Most of these models are developed based on small-scale branch, where the ratio of the branch diameter to the horizontal pipe diameter is less than or equal to 0.2 (d/D ≤ 0.2). Therefore, these models are not suitable to predict the onset of liquid entrainment through a large-scale branch. In addition, these models are developed for a specific branch angle (typically 0 or 90°) and therefore, are incapable of making good predictions of the onset of liquid entrainment through a large-scale branch inclined at other angles. In order to address these issues, we conducted experiments to investigate the onset of liquid entrainment through a large-scale branch pipe (d/D > 0.6) inclined at three angles (32.2, 47.9, and 62.3°) and we assessed the mass flow quality of the branch. By analyzing the mathematical models for liquid entrainment currently available and by theoretical deduction, we developed new correlations to predict the onset of liquid entrainment and mass flow quality. We found that the values predicted by these correlations fit well with the experimental data with a maximum error of ±35%. Both of these liquid entrainment correlations provide good predictions of liquid entrainment through a large-scale branch inclined at an angle of 32.2, 47.9, and 62.3°. We also obtained some meaningful conclusions based on the experimental data. We found that at the onset of liquid entrainment, under similar experimental conditions, the critical Froude number Frg decreases with an increase in the branch angle. In addition, the larger the branch angle, the lower the effect of the branch scale on the onset of liquid entrainment. There are two primary factors that influence the liquid entrainment process: (1) gas chamber height—the liquid entrainment process is promoted as the gas chamber height decreases, and (2) vertical component of the inertial force—the liquid entrainment process is weakened with a decrease in the vertical component of the inertial force. This indicates that the gas chamber height dominates the liquid entrainment process at relatively large branch angles whereas the vertical component of the inertial force dominates the liquid entrainment process at small branch angles.

Changes in future climate will alter the geographic distributions of many species. Species distribution models have evolved as a powerful tool for predicting potential species distributions and assessing habitat suitability. The Asian Great Bustard (Otis tarda dybowskii), a long-distance migratory bird, is listed as a globally threatened species and is highly dependent on farmlands during the wintering period. In this study, 78 occurrence points and 15 environmental variables were used to estimate the potential distribution under current conditions and four future climate scenarios by using the maximum entropy model. With current climatic conditions, the highly suitable areas of wintering Asian Great Bustard in China were mainly concentrated on the Northeast Plain, Guanzhong Plain, and North China Plain (33–48° N, 109–127° E). Under future climatic scenarios, the geographic distribution of wintering Asian Great Bustard would remain stable, and the total area of suitable habitats would increase to varying degrees until the end of this century. Our results can be used to define highly suitable areas for conservation management plans for this threatened species.

The presence of surfactant could accelerate the hydrate formation dramatically, which is of great significance for the industrial application of the hydrate-based technologies. In this study, the micro-morphologies of the hydrate particles and the process of hydrate formed along the reactor wall was investigated using a high-speed camera. How the hydrate formed on the wall and the way the liquid phase migrated upward for the hydrate formation were intuitively exhibited, mechanisms for the adherent growth process and the different growth patterns were also proposed. It could be found that the hydrate particles formed in the Sodium Dodecyl Sulphate (SDS) solution was needle-shaped, and five aggregation forms were observed. The presence of SDS could make the critical size smaller and thus a lower energy barrier, both of which are facilitate to the hydrate nucleation and the further massive hydrate formation. When hydrate started to form on the wall, hydrate particles were accumulated and consolidated at the liquid–gas interface firstly, then stuck on the wall. Liquid phase could migrate upward through the porous hydrate under the capillary force for the further hydrate formation. In addition, the liquid film at the growth frontier and the condensate distributed on the wall were conducive to the moving of the growth frontier and the final hydrate formation. This work provides insights on the hydrate formation characteristics in SDS solution which facilitates to the rapid formation of hydrate and thereby promotes the industrial applications of the hydrate-based technologies.

A tomographic reconstruction method is developed for the visible light imaging diagnostic system of Experimental Advanced Superconducting Tokamak (EAST) to provide the emissive profile on the poloidal cross section of the divertor region. Weight matrix is calculated by a ray tracing method according to the optical path of the visible light imaging diagnostic system in the delicate three-dimensional grid model of EAST first wall to avoid the influence of complex structures of the divertor region. The Philips-Tikhonov regularization algorithm with second-order correction is adopted to calculate the emissive profile. The phantom tests are performed and the effectiveness of the method is confirmed with signal to noise ratio (SNR) at 50. The method is applied to the experimental images detected by the visible light imaging diagnostic and clear peaks are identified in the reconstructed emission profiles, which is in consistent with the radiation belts observed in the experimental images.

Nerve terminals contain multiple sites specialized for the release of neurotransmitters. Release usually occurs with low probability, a design thought to confer many advantages. High-probability release sites are not uncommon, but their advantages are not well understood. Here, we test the hypothesis that high-probability release sites represent an energy-efficient design. We examined release site probabilities and energy efficiency at the terminals of two glutamatergic motor neurons synapsing on the same muscle fiber in Drosophila larvae. Through electrophysiological and ultrastructural measurements, we calculated release site probabilities to differ considerably between terminals (0.33 versus 0.11). We estimated the energy required to release and recycle glutamate from the same measurements. The energy required to remove calcium and sodium ions subsequent to nerve excitation was estimated through microfluorimetric and morphological measurements. We calculated energy efficiency as the number of glutamate molecules released per ATP molecule hydrolyzed, and high-probability release site terminals were found to be more efficient (0.13 versus 0.06). Our analytical model indicates that energy efficiency is optimal (∼0.15) at high release site probabilities (∼0.76). As limitations in energy supply constrain neural function, high-probability release sites might ameliorate such constraints by demanding less energy. Energy efficiency can be viewed as one aspect of nerve terminal function, in balance with others, because high-efficiency terminals depress significantly during episodic bursts of activity.

This paper research the phenomenon that the engine bolts would creep under the preload and the high temperature in the operation process, and creep could cause the degradation of preload leading to engine failure. Through the high-temperature creep test and the stress relaxation test, the creep curve and stress relaxation curve are obtained. With the data of creep test, a method is proposed to find the turning time from the rapid stage to the steady stage of creep process more accurately. Then the retightening operation is applied at the turning time under the same test conditions to optimize the bolt assembly and the new stress relaxation curve could be obtained. According to the data before and after optimization, the life distributions of bolt could be estimated by the method of mathematical statistics.

In the southeastern Sichuan Basin, the Wufeng–Longmaxi Formations are major strata used for shale gas exploration and development. Although the Fuling shale gas field—the largest Lower Paleozoic shale gas field in the world—has already been developed, shale gas wells in other parts of this area apart from the Jiaoshiba anticline vary greatly in production capacity. Microstructures and inclusion homogenization temperatures were analyzed for venous fluid inclusions in samples taken from the main shale gas wells in the Wufeng–Longmaxi Formations and were combined with simulated burial–thermal histories, hydrocarbon generation and expulsion histories, and fracture formation–closure times and stages to determine how fracture and fluid activities influenced shale gas preservation/destruction conditions. Veins were composed of quartz, calcite, and quartz–calcite and contained gas–liquid two-phase brine and high-density methane inclusions. Combined with simulated burial–thermal histories, the results showed that fracture-fluid activity time could be inferred from inclusion homogenization temperatures and was consistent with gas content and output of shale gas wells. The deeper and earlier the vein formation, the more favorable the preservation conditions of the shale gas reservoir. Furthermore, the more the fracture formation–closure stages and the lower the inclusion homogenization temperature, the more severe damage to the shale gas reservoir has happened. Clearly, in areas from Jiaoshiba to Pingqiao, Nanchuan, and Dingshan in the southwest, increasing the number of paleo-fluid activity and vein formation stages, as well as later paleo-fluid activity time, worsened shale gas preservation conditions. The results can act as a reference for studying fracture-fluid activity, enrichment, and preservation of shale gas in the southeastern Sichuan Basin and other parts of the world.

In the manufacturing of metallic parts, the machining process is a critical factor for ensuring product quality. Machining condition monitoring is essential for the intelligent process. Existing machining condition monitoring approaches usually detect abnormal conditions for a fixed machining procedure, which is unrealistic and impractical for real practical applications. In this paper, a novel generalized machining condition monitoring approach based on control chart pattern recognition (CCPR) with dynamically-sized observation windows for online data is proposed. More precisely, two critical issues are addressed. First, the development of a CCPR model that handles patterns with stochastic sample size. Second, a procedure for selecting the window size for detecting abnormal machining conditions. An information fusion framework is implemented to assist the machining conditions monitoring by combining data from multiple sensors and multiple sized observation windows. Experiments are conducted to validate the feasibility of the proposed approach for two machining processes with the different cutting parameters. The results demonstrate the applicability of the proposed approach for conducting condition monitoring for machining process under different machining environments as needed in practice.

The effect of the growth temperature and V/III flux ratio on the morphology and microstructure of GaAs nanowires grown on GaAs (1 1 1)(B) substrates by Au-assisted molecular beam epitaxy with solid As-4 source was investigated. It has been found that a low growth temperature of 400 degrees C can result in defect-free wurtzite structured nanowire with syringe-like morphology, while nanowires with more homogeneous diameter can be obtained at high temperatures (500 degrees C and 550 degrees C) with many stacking faults. It was also found that, at a low V/III flux ratio, GaAs nanowires had a shrinking neck section, while a high V/III flux ratio may result in disappearance of the shrinking necking section. For the Ga very rich condition, a phase separation of the catalysts can be observed, leaving a small Au-Ga droplet covered by the outer pure Ga droplet. (C) 2013 Elsevier B.V. All rights reserved.

Jumping bristletails (Archaeognatha) have flagellate antennae with frequent breakpoints, structures destined to break when undue mechanical stress is applied. In natural populations of Petrobius brevistylis at least 67% of animals had broken antennae. In twenty-four trials, all antennae broke at a breakpoint under the animal's weight. Breakpoints consist of two cylinders of laminated cuticle, one stuck inside the other. For half the length of the breakpoint the cylinders are separated by a non-laminated layer of cuticle; thus a tripartite cuticle is formed. During a breakage, the two cylinders slide apart along that non-laminated middle layer that seems to act like a lubricant. While the cylinders pull apart, a thin cuticle unfolds that closes off the new tip of the antenna formed by the outer breakpoint cylinder. Later on, the cylinder is not replaced by a new terminal antennomere. Instead, the antennomere directly proximal to a breakpoint, i.e. the one that after the break forms the last antennomere, already possess the same complement of sensilla as the original terminal antennomere. This includes sensilla basiconica Type A and B found exclusively on these antennomeres and the original terminal antennomere. Breakpoints are common to Archaeognatha and Thysanura, insects that moult throughout their lifetime.

M-phase LiNb0.6Ti0.5O3 (LNT) plate-like particles with large anisometric shape were firstly fabricated by molten salt synthesis (MSS) method in LiCl flux. Effects of reaction temperature, holding time and the weight ratio of LiCl salt to the original powders on the phase structure and morphology of the synthesized particles were investigated. The LiNb0.6Ti0.5O3 powders generally showed a multi-layer structure, exhibiting irregular hexagonal or triangle morphology. The reaction temperature showed a strong influence on the particle growth process, and pure LNT particles are obtained at 950 °C. Further increasing the reaction temperature and holding time could increase the average size of the particles. It revealed that the thickness of the plat-like particles was increased as the contents of the chloride salts increased. The synthesis process, the relation between crystal structure and morphology of particles were also discussed. © 2011 Elsevier B.V. All rights reserved.

In this study, a continuous biofilm decolorizing system with high efficiencies of dye degradation and textile wastewater treatment was established using selected fungal consortium. Function and persistence of this fungal consortium were assessed using traditional and molecular biological methods along with near 4 months running process under non-sterile conditions. The microbial cultivation results indicated that the colony forming units (CFUs) ratio of fungi to bacteria stabilized between 51.8:1 and 6.8:1 under the influent conditions of various simulated and real textile wastewater. Clone libraries and phylogenetic trees of bacteria and fungi were respectively constructed based on their full length 16S and partial 26S rRNA gene sequences retrieved from the biofilm at the end of the system running. The results indicated that the dominant population preserved in the system was yeasts belonging to genus Candida. While most of the filamentous fungi isolated from the enrichment consortium could not be preserved on the biofilm. Among the three fungal isolates with high efficiency of dye decolorization, only Candida tropicalis was retrieved and occupied near 70% in the fungal clone library. 26.5% of the retrieved fungal sequences were grouped with some species of Trichoderma which did not exhibit dye decolorization abilities. Compared to the fungal phylogenetic tree, diversity of bacteria was far higher. 67.9% of the retrieved bacterial sequences were clustered into Alphaproteobacteria.

Summary Many types of synapses have highly characteristic shapes and tightly regulated distributions of active zones, parameters that are important to the function of neuronal circuits. The development of terminal arborizations must therefore include mechanisms to regulate the spacing of terminals, the frequency of branching, and the distribution and density of release sites. At present, however, the mechanisms that control these features remain obscure. Here, we report the development of supernumerary or "satellite" boutons in a variety of endocytic mutants at the Drosophila neuromuscular junction. Mutants in endophilin , synaptojanin , dynamin , AP180 , and synaptotagmin all show increases in supernumerary bouton structures. These satellite boutons contain releasable vesicles and normal complements of synaptic proteins that are correctly localized within terminals. Interestingly, however, synaptojanin terminals have more active zones per unit of surface area and more dense bodies (T-bars) within these active zones, which may in part compensate for reduced transmission per active zone. The altered structural development of the synapse is selectively encountered in endocytosis mutants and is not observed when synaptic transmission is reduced by mutations in glutamate receptors or when synaptic transmission is blocked by tetanus toxin. We propose that endocytosis plays a critical role in sculpting the structure of synapses, perhaps through the endocytosis of unknown regulatory signals that organize morphogenesis at synaptic terminals.

Wiring economy has successfully explained the individual placement of neurons in simple nervous systems like that of Caenorhabditis elegans [ [1] , [2] and [3] ] and the locations of coarser structures like cortical areas in complex vertebrate brains [4]. However, it remains unclear whether wiring economy can explain the placement of individual neurons in brains larger than that of C. elegans. Indeed, given the greater number of neuronal interconnections in larger brains, simply minimizing the length of connections results in unrealistic configurations, with multiple neurons occupying the same position in space. Avoiding such configurations, or volume exclusion, repels neurons from each other, thus counteracting wiring economy. Here we test whether wiring economy together with volume exclusion can explain the placement of neurons in a module of the Drosophila melanogaster brain known as lamina cartridge [ [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] and [13] ]. We used newly developed techniques for semiautomated reconstruction from serial electron microscopy (EM) [14] to obtain the shapes of neurons, the location of synapses, and the resultant synaptic connectivity. We show that wiring length minimization and volume exclusion together can explain the structure of the lamina microcircuit. Therefore, even in brains larger than that of C. elegans, at least for some circuits, optimization can play an important role in individual neuron placement., We are grateful to Richard Fetter for assistance in EM imaging and Janelia FlyEM Project Team and Aljoshcha Nern for helpful comparisons with images from Gal4-driven expression of green fluorescent protein in lamina cells. M.R.-A. acknowledges a Formación del Personal de Investigación (FPI) fellowship from Ministerio de Ciencia e Innovación (MICINN) and support from the Janelia Farm Research Campus (JFRC) (Howard Hughes Medical Institute [HHMI]) visitor program; G.G.d.P. acknowledges funding by MICINN (Spain) as Plan Nacional, including a FPI fellowship, and as partners of the ERASysBio+ initiative supported under the EU ERA-NET Plus scheme in FP7, and support from the JFRC (HHMI) visitor program. I.A.M. also acknowledges support from the JFRC (HHMI) visitor program.