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The highly enantioselective desymmetrization of prochiral cyclopent-4-ene-1,3-diones has been developed via an organocatalytic Michael reaction. This desymmetrization protocol is efficiently catalyzed by 10 mol% of a bifunctional squaramide, offering a short entry into a series of cyclopentane-substituted oxindoles bearing two quaternary and one tertiary stereocenters in good yields and high stereoselectivities.

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH2Cl2 extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H2O2. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H2O2 and the C-geranyl substituent may be an important factor because of its lipophilic character.

Favorable electrostatic interactions dominate the packing of three halogen-substituted pyridinium salts with chloride or tetrachloridometallate counteranions. The electron density in these solids was determined based on high resolution X-ray diffraction experiments. Residues carrying opposite charges subtend short interhalogen contacts X···X in which the anionic chlorides act as electron donors and the cationic halogen substituents of the pyridinium cations act as acceptors. The X···X interactions coexist and in part compete with classical N–H···Cl hydrogen bonds. Properties derived from the experimental charge density such as the position of the bond critical point, electron density, Laplacian and energy densities help to establish the relevance of the competing interactions. Multipole-derived charge densities allow classification of short contacts more reliably than exclusively geometry-based analyses and simple promolecule densities.

In the past decade, intensive research has proved that the cyclonic-static micro bubble flotation column (FCSMC) is an efficient flotation device which can be used to separate fine-grained minerals. The main way to strengthen the recovery of fine-grained minerals is further improvement of the highly-turbulent flow field of the pipe flow unit in the flotation column. With a decrease of fine-grained mineral diameter, the turbulence intensity in the pipe flow should be increased so as to strengthen the recovery of the fine-grained mineral. In this paper, the effect of vortex generators (VGs) on the turbulence kinetic energy and the turbulence dissipation rate in a pipe flow unit are primarily investigated by numerical simulations. The results showed that a staggered arrangement (S=20 mm) exhibited the maximum volume-averaged turbulence kinetic energy and volume-averaged turbulence dissipation rate among different arrangements of VG arrays in the pipe flow unit. Streamwise vorticity was formed behind the VGs along the flow direction. With an increase of VG arrays from 0 to 5, the volume-averaged turbulence kinetic energy increased from 0.015 m2/s2 to 0.05 m2/s2. Similarly, with an increase of VG arrays from 0 to 5, the volume-averaged turbulence dissipation rate in the pipe flow unit increased from 1.99 m2/s3 to 11.8 m2/s3. A flotation experiment using coal slime was conducted by using different structures of pipe flow unit (including empty pipe and pipe with different VG arrays). The results showed that cumulative yield and combustible recovery were greatly improved due to the influence of VG arrays. The results of the study are equally beneficial in helping understand the recovery of fine-grained minerals in other separation equipment.

Electricity demand forecasting is an important basis for planning power development and guiding power construction. Accurate electricity consumption prediction in the whole society can effectively avoid power waste. Based on the relationship between various industries and electricity consumption of provincial power companies, a power consumption prediction model based on VEC model was established. The actual electricity consumption data of each industry in each month was used as the model input quantity, and it is 3-12 in 2019 in Shanxi Province. Forecasting electricity consumption of industry in each month becomes crucial.

Objective: The present study aimed to evaluate insulin-like growth factor 2 antisense (IGF2-AS) in the villi of human embryos and compared its expression between normal pregnancy and early pregnancy loss (EPL). Materials and methods: The present study conducted a microarray analysis to identify the expression profiles of lncRNAs in villi from EPL and normal controls (controls, n = 10 and EPL patients, n = 10). Embryonic villi were collected from women who underwent artificial abortion. QPCR was used to confirm the results. The DNA methylation patterns were analyzed using pyrosequencing and bisulfite sequencing polymerase chain reaction. The percentage of methylation was compared in chorionic villi from the two groups. Results: A total of 57 deregulated differentially expressed lncRNAs were detected, of which 33 were upregulated, and 24 were downregulated. The expression of lncRNA IGF2-AS was downregulated significantly in EPL villi compared with the normal villi. Negative regulation of IGF2-AS may be involved in the development of EPL. Methprimer predicted that IGF2-AS promoter had CpG islands and dense CG sites. Increased methylation at CpG islands present in IGF2-AS gene promoter was observed in EPL villi. Conclusion: An increase in methylation of IGF2-AS likely leads to its downregulation in chorionic villi of EPL. The findings suggest that a deficiency of IGF2-AS in the villi is associated with human EPL. Keywords: Early pregnancy loss, Villus, IGF2-AS, Methylation

Field experiments were conducted to examine the effects of flooding irrigation (FI), micro-sprinkler irrigation (SI), drip irrigation (DI), combined with nitrogen application (N为探明玉米秸秆还田下小麦的合理灌溉与施肥方法,于田间研究了漫灌(FI)、微喷灌(SI)、滴灌(DI)和灌水施氮模式(N

The light-atom com­pound (2S)-methyl (Z)-5-(2-tert-but­oxy-1-cyano-2-oxo­ethyl­idene)pyrrolidine-2-carboxyl­ate is an enanti­opure coordination partner for cations. Despite its only minor resonant scattering, the absolute structure was determined by a combination of diffraction, CD spectroscopy and theoretical calculations., The enanti­opure monopyrrolidine derivative (2S)-methyl (Z)-5-(2-tert-but­oxy-1-cyano-2-oxo­ethyl­idene)pyrrolidine-2-carboxyl­ate, C13H18N2O4, (1), represents a potential ligand and an attractive inter­mediate for the synthesis of chiral metal com­plexes. At the mol­ecular level, the com­pound features an intra­molecular N—H⋯O hydrogen bond; neighbouring mol­ecules inter­act via N—H⋯N contacts to form chains along [100]. Due to its elemental com­position, resonant scattering of the target com­pound is entirely insignificant for diffraction experiments with Mo Kα and small even for Cu Kα radiation. A preliminary study with the harder radiation type confirmed the chiral space group and the suitability of the single crystal chosen; as expected, the results concerning the absolute structure remained com­pletely inconclusive. A second data collection with the longer wavelength gave satisfactory quality indicators for the correct handedness of the mol­ecule, albeit with high standard uncertainties. The absolute configuration has been assessed independently: CD spectra for both enanti­omers of the target mol­ecule were calculated and the spectrum for the S-configured stereoisomer was in agreement with the experiment. The Cotton effect of (1) may be ascribed to π–π* transitions from HOMO to LUMO and from HOMO to LUMO+1. As both independent techniques agree with respect to the handedness of the target mol­ecule, the absolute structure may be assigned with a high degree of confidence.

Customers' demands have become more dynamic and complicated owing to the functional diversity and lifecycle reduction of products which pushes enterprises to identify the real-time needs of distinct customers in a superior way. Meanwhile, social media turned as an emerging channel where customers often spontaneously can express their perceptions and thoughts about products promptly. This paper examines the customer satisfaction identification and improvement problem based on social media mining. First, we proposed the public opinion sensitivity index (POSI) to uncover target customers from extensive short-textual reviews. Subsequently, we presented a customer segmentation approach based on the sentiment analysis and the variable-scale clustering (VSC). The approach is able to get several customer clusters with the same satisfaction level where customers belonging to each cluster have similar interests. Finally, customer-centered marketing strategies and customer difference marketing campaigns are planned under the shadow of customer segmentation results. The experiments illustrate that our proposed method can support marketing decision marketing in practice that enriches the intention of the current customer relationship management.

Jointly influenced by natural factors and artificial protection measures in recent years, the vegetation coverage of the Loess Plateau has significantly increased. However, extensive vegetation recovery can result in massive water consumption and a severe soil water deficit, which poses a great threat to the sustainable development of the regional ecological system. Maintaining the balance between precipitation and water consumption is an important foundation of ecological security in the Loess Plateau. Based on this, the present study used the GRACE (Gravity Recovery and Climate Experiment) gravity satellite data to simulate the annual actual water consumption from 2003 to 2014 and to analyze the temporal and spatial evolution of the regional precipitation and the actual evapotranspiration (AET). This study also applied the newly developed rainwater utilization potential index (IRUP) to quantify the sustainability of the water balance in the Loess Plateau. The spatial-temporal patterns of precipitation, potential evapotranspiration, and AET from 2003 to 2014 in the Loess Plateau were all analyzed in this study. Based on the results, the annual average precipitation (AAP) and AET in the entire Loess Plateau had significant increasing trends. The analysis of the spatial distribution reveals that the AET was decreasing from the southeast to the northwest in the Loess Plateau. However, the average values of potential evapotranspiration did not obviously change. Based on the estimated AET result, it was determined that the average IRUP had an increasing trend. The increase in the IRUP is due to an increased rate of precipitation that is statistically higher than that of the AET. Consequently, the Loess Plateau experienced a wetting trend during the period of 2003–2014, especially after the Grain for Green project was implemented. The results in this paper were proven by using three different depths of ERA-Interim (a global atmospheric reanalysis product created by the European Centre for Medium-Range Weather Forecasts) soil water content data from the same period and the observed runoff data from 18 different hydrological sites. Consequently, it seems that the vegetation could maintain a sustainable growth with the implementation of the Grain for Green Project.

Two light-activated NO donors [RuCl(qn)(Lbpy)(NO)]X with 8-hydroxyquinoline (qn) and 2,2′-bipyridine derivatives (Lbpy) as co-ligands were synthesized (Lbpy1 = 4,4′-dicarboxyl-2,2′-dipyridine, X = Cl− and Lbpy2 = 4,4′-dimethoxycarbonyl-2,2′-dipyridine, X = NO3−), and characterized using ultraviolet–visible (UV-vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (1H NMR), elemental analysis and electrospray ionization mass spectrometry (ESI-MS) spectra. The [RuCl(qn)(Lbpy2)(NO)]NO3 complex was crystallized and exhibited distorted octahedral geometry, in which the Ru–N(O) bond length was 1.752(6) Å and the Ru–N–O angle was 177.6(6)°. Time-resolved FT-IR and electron paramagnetic resonance (EPR) spectra were used to confirm the photoactivated NO release of the complexes. The binding constant (Kb) of two complexes with human serum albumin (HSA) and DNA were quantitatively evaluated using fluorescence spectroscopy, Ru-Lbpy1 (Kb~106 with HSA and ~104 with DNA) had higher affinity than Ru-Lbpy2. The interactions between the complexes and HSA were investigated using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and EPR spectra. HSA can be used as a carrier to facilitate the release of NO from the complexes upon photoirradiation. The confocal imaging of photo-induced NO release in living cells was successfully observed with a fluorescent NO probe. Moreover, the photocleavage of pBR322 DNA for the complexes and the effect of different Lbpy substituted groups in the complexes on their reactivity were analyzed.

In this paper, the titanium nitride/copper calcium titanate (TiN/CCTO) composites were prepared by low-temperature sintering. The negative permittivity was observed when TiN content exceeded 50 wt% due to plasma oscillation phenomenon, and the weakly negative permittivity was ascribed to a moderate electron density in TiN/CCTO composites. Meanwhile, the alternating current (AC) conduction behavior was transformed from hopping to metal-like along with a skin effect. Furthermore, the equivalent circuit analysis indicated that the positive reactance values were responsible for negative permittivity, leading to the inductive character in TiN/CCTO composites. The fabricated TiN/CCTO binary ceramic composites with tunable and weakly negative permittivity are devoted to promoting the research in novel capacitors and attenuation.

In this study, a novel flotation recovery model based on a first-order kinetics is proposed. The collision efficiency in the recovery model was directly obtained from 3D computational fluid dynamics (CFD) simulations involving a single-bubble-multi-particle aggregate system with typical flotation operating conditions (bubble diameter of 1 mm and particles diameter of 30 μm). The effect of the fluctuating flow field on collision was accounted using a large eddy simulation (LES) turbulence model for two turbulence intensity cases namely 4% and 20%, respectively. It was noted that the collision efficiency decreased in the radial direction away from the symmetry axis of the bubble. The normalized equivalent critical radius K1 for the overall collision efficiency, was found to be optimum at the lower turbulence intensity of 4%. A maximum bubble surface loading, 0.142 was determined by fitting the model-predicted bubble velocity with available experimental data. With this maximum bubble surface loading constraint, the recovery model predicted two regimes namely a loading regime in the early flotation period and a saturated regime wherein the bubble loading capability was entirely exhausted. Simulation of a batch flotation system suggested that loss in bubble surface loading capacity occurred faster in a dense pulp compared to a dilute pulp system and the predicted recovery decreased with increasing solids concentration for the same gas volume fraction. Similar to the collision efficiency, the optimum recovery was obtained at Ti = 4%. Further, the model predicted recovery was compared to a lab scale coal flotation test and reasonable agreement was obtained.

The net anthropogenic nitrogen input (NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessment and management. This paper calculated NANI in the upper Yangtze River basin (YRB), upstream of the Three Gorges Dam (TGD), from 1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km - 2 to 4931 kg N km - 2. The major components were fertilizer N application, atmospheric N deposition, and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir.

Bubble behaviors in the gas–liquid and lab-scale cyclonic-static micro-bubble flotation column (FCSMC) were investigated and optimized. By particle image velocimetry and charge-coupled device camera, bubble velocity and migration under low and high gas holdup conditions were measured. The particle image velocimetry measurement under low gas holdup shows that the swirling was significantly stronger than the rising in the near-axis area, and it declined as height increased. The central region contained high gas holdup and velocity. The bubble distribution under high gas holdup revealed that, in the column flotation unit, when water circulation rate (qw) increased, gas concentration moves toward the bottom. An excessively high qw drove gas downward and even caused the gas to be pulled into the pump. When aeration rate (qg) increased, the radial distribution improved but was not significant. If qg was excessive, the gas amount increased toward the top due to reflux when the rising bubbles met the free surface. Specifically, the greater bubble concentration in central region was observed under most test conditions. Additionally, an elongated ‘air column’ existed along the central axis and became more obvious with a high qw. The cyclonic inverted cone structure resulted in the gas gathering toward the center and the air column phenomena that deteriorate bubble mineralization. A non-uniform filling method was proposed to optimize the flow field. Filling with non-uniform sieve plates was proved to be more effective on bubble distribution equalization, air column inhabitation and non-axial velocity decreasing. These results provide the basis for structure optimization and process regulation of cyclonic-static micro-bubble flotation column. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.

A strategy for the NHC-catalyzed asymmetric synthesis of spirobenzazepinones, spiro-1,2-diazepinones, and spiro-1,2-oxazepinones has been developed via [3+4]-cycloaddition reactions of isatin-derived enals (3C component) with in-situ-generated aza-o-quinone methides, azoalkenes, and nitrosoalkenes (4atom components). The [3+4] annulation strategy leads to the seven-membered target spiro heterocycles bearing an oxindole moiety in high yields and excellent enantioselectivities with a wide variety of substrates. Notably, the benzazepinone synthesis is atroposelective and an all-carbon spiro stereocenter is generated.

Polymorphism is a challenging phenomenon and the competitive packing alternatives which are characteristic for polymorphs may be encountered for essentially rigid molecules. A second crystal form of the well known compoundo-nitrobenzoic acid, C7H5NO4, an important intermediate in the production of dyes, pharmaceuticals and agrochemicals, is described. Although obtained serendipitously, its intra- and intermolecular features match expectations from database searches and theoretical calculations. O—H...O hydrogen-bonded carboxylic acid dimers represent the building blocks in both polymorphs. For steric reasons and in agreement with a calculated potential energy surface, the carboxylic acid and nitro groups cannot simultaneously be coplanar with the benzene ring but have to tilt. In the well established crystal form, this out-of-plane torsion is more pronounced for the nitro substituent. In contrast, the new polymorph is characterized by a major tilt of the carboxylic acid group. The molecules in both alternative crystal forms achieve a similar compromise with respect to acceptable intramolecular O...O contacts.

A field micro-plot experiment was conducted to study the effect of early-stage regulated deficit irrigation (RDI) on the stress tolerance of winter wheat in the late growth stage. Plants were subjected to two RDI treatments: proper water deficits (45-55% field water capacity) were imposed during tillering—the beginning of the spring growth stage (T1) and during the beginning of spring growth to the end of the stem elongation stage (T2). The control plants (CK) were maintained with an adequate water supply until anthesis. The results showed that T1 and T2 shortened the length of the first and second internodes, and increased their weight per unit length, and thereby enhanced stem lodging resistance. Although post-anthesis drought and waterlogging lowered leaf photosynthetic rate and root respiration rate, the two RDI treatments improved significantly compared to the control. The two RDI treatments had no significant effects on grain yield under post-anthesis well-watered conditions but increased grain yield and yield stability of wheat under post-anthesis water stress. In addition, T1 and T2 significantly reduced water consumption and increased water productivity (WP) of wheat compared to the control. In summary, this study shows that appropriate RDI at early growth stages increased grain yield and yield stability through improving population characteristics, root respiration and photosynthesis of plants under post-anthesis water stress conditions. Copyright © 2016 John Wiley & Sons, Ltd.

The yttrium iron garnet composites containing carbon particles with different carbon content were prepared by the impregnation-carbonization process. The dielectric and magnetic properties have been investigated experimentally in the frequency range from 10 MHz to 1 GHz. When the carbon content increased to 13 wt%, the carbon particles interconnected with each other, leading to the formation of conductive network. The plasma oscillation of delocalized electrons resulted in the negative permittivity. The negative permittivity behavior was analyzed by Drude model. The fitting result indicated that the plasma frequency of the composite was 7.09 GHz. Meanwhile, the composite with 13 wt% carbon content presented the negative susceptibility in the frequency range from 300 MHz to 1 GHz due to the combined contribution of magnetic resonance and diamagnetic response. Keywords: Double negative materials, C/YIG composites, Percolation threshold, Low frequency plasmonic state

Desertification land occupies vast area of world, which is a big threat to eco-environmental safety and brings huge economic losses. Wind erosion is a key process and ecological problem of land desertification in arid and semi-arid area, where unreasonable land use is one of major causes. Therefore, optimizing land use is a substantially effective approach to eco-environmental safety and development of sandy area. Yuyang County, located in Mu Us Desert of semi-arid sandy area and farming-pastoral zone in North China, was selected as a typical study area. The principles and methods on environmentally friendly land use planning surrounding urban area for combating soil wind erosion were constructed, and a “tri-circle” land use paradigm around Yulin City was worked out. It was predicted that by the year of 2020, farmland will be only 10 percent of total area of Yuyang County, which are able to meet the need of food and meat. The proportion of ecological land, productive land and living land would be 2.27:12.09:85.64, which will lead to a reasonable land use system for ecological security and social-economic sustainable development of the region. It shows that this research will help construct the sustainable land use system under ecological security, and ensure habitat environmental safety in urban area.

The thermal motion of atoms in crystals is quantified by anisotropic displacement parameters (ADPs). Here we show that dispersion-corrected periodic density-functional theory can be used to compute accurate ADPs for transition metal carbonyls, which serve as model systems for crystalline organometallic and coordination compounds.

A random metamaterial, carbon/alumina (C/Al2O3) composite, was prepared using a precursor infiltration and pyrolysis method, which has potential applications in novel antennas, microwave absorbing and shielding. The microstructures, radio-frequency dielectric property and conductivity behavior of the composites with different carbon contents were investigated in detail. It was found that the carbon membrane spread out on the pore walls of the alumina matrix. As the carbon content increased, the composites underwent a percolation phenomenon, and the conductive mechanism changed from hopping conduction to metal-like conduction due to the formation of conductive carbon networks. A negative permittivity behavior was observed in the composites above the percolation threshold, and this was ascribed to the low frequency plasmonic state produced by the carbon networks. The frequency dispersion of such negative permittivity efficiently agreed with the Drude model. The negative magnitude of permittivity in the testing frequency was small, ranging from −370 to −28, which originated from the lower carrier concentration in the conducting carbon networks. This work will greatly facilitate the practical application of random metamaterials with tunable electrical properties, and has great significance for the development of metamaterials.

A highly stereoselective organocatalytic 1,6-conjugate addition of 3-substituted oxindoles to para-quinone methides to construct all-carbon quaternary stereocenters is described. In the presence of 10 mol % of a bifunctional squaramide organocatalyst, this 1,6-addition reaction occurs with excellent yields, diastereoselectivities and very good enantioselectivities, providing an efficient approach to a series of oxindole derivatives containing the diarylmethine motif attached to an all-carbon quaternary stereogenic center.

Understanding the spatiotemporal distribution of nonpoint-source pollutant river loads from catchments and their influences on the water quality along river networks in a large river basin is important for land management and water quality protection. In this study, a geomorphology-based nonpoint-source pollution (GBNP) model was applied to the upper Yangtze River basin (YRB) to analyze the nitrogen loads into the river network, as well as its influences on river water quality. Based on the simulation, we analyzed the spatial and temporal distribution of nonpoint-source nitrogen loads into river networks and the nitrogen retention along the river network. The results illustrated that the annual total nitrogen (TN) loads from the fields/hillslopes into the rivers ranged from 55 × 104 t to 392 × 104 t on average during 1990–2012 in the upper YRB. The export coefficient (the ratio of river TN load to TN input of the same sub-catchment) over the upper YRB varied from 0.04 to 0.82 and had a mean value of 0.26. The spatial variability in the annual TN load (TN load intensity) significantly influenced the export coefficient magnitudes in different tributaries. The river nitrogen retention ratio varied from 3.84% to 85.50%, and Minjiang (MJ) had the highest value among all tributaries. The nitrogen retention ratio was higher in spring and winter than in summer and autumn in all tributaries. Both temperature and stream flow conditions (discharge and velocity) were the major factors that influenced river nitrogen retention. In general, a higher TN load from the catchment resulted in a higher river TN concentration due to the “lift-up and carry-away” functions of the catchment rainfall-runoff processes. However, when the net anthropogenic nitrogen input (NANI) was low, the TN load was also relatively low, and the high flow could dilute the river nitrogen concentration. When the TN load was adequately high, the river flow dilution could disappear, and the river TN concentration had the same pattern as the river discharge.

One monocapped square-antiprismatic Ba(II) coordination polymer [Ba4(L)2(H2O)8·H2O]n (Ba-CP1, H4L ​= ​1,1’-(1,4-phenylenebis(methylene))bis(1H-pyrazole-3,5-dicarboxylic acid), was designed and synthesized via self-assembly processes. Structure of the complex was characterized by X-ray single crystal analysis, with features of Ba–O metal-inorganic chains linked to carboxylate oxygen atoms from a six-dentate flexible chelating ligand to construct a complicated 3D Ba-metal-organic framework. Optically, luminescent investigations show that this Ba-CP is an excellent CP-based fluorescent probe, with high sensitivity for environmentally relevant Fe3+ and Cr2O72− ions. This is the first Ba-CP dual-responsive fluorescent material recognizing Fe3+ or absorbing Cr2O72− ions in DMF solution.

In recent years, the tea plant (Camellia sinensis [L.] Kuntze) has been widely planted in Guizhou Province, China, with a cultivated area of 350,000 ha in 2017. In November 2018, leaf spots were observed on tea plants in Yuqing County (27.22°N, 107.88°E). Disease incidence was estimated at 74 to 82%, and disease severity was estimated at 42 to 48% in 12 tea plantations. Early symptoms on infected leaves were light brown lesions, which gradually enlarged to brown, scattered, round, elliptical or irregular lesions. The central area of each lesion later became grayish and surrounded by an inconspicuous yellow halo. Neighboring lesions coalesced to form larger lesions at the margin of the leaves. In order to identify the pathogen(s) causing this disease, lesion margins of the sampled leaves (n = 10) were surface sterilized with 75% ethanol for 30 s, soaked in 0.5% sodium hypochlorite for 5 min, rinsed three times in sterilized water, plated on potato dextrose agar (PDA), and incubated for 3 to 5 days in darkness at 25°C. The hyphal tips from the edge of growing colonies were picked and transferred to fresh PDA plates. Colonies were initially pale yellow and gradually became grayish-white, producing masses of flocculent aerial hyphae. At 22 days postinoculation, black, spherical, scattered or clustered pycnidia were evident, 50 to 290 μm in diameter. Their shape was globose or irregular, with one to two ostioles. Pycnidia were nonpapillate or slightly papillate, with the pycnidial wall consisting of two to three layers of cells. Unicellular and hyaline conidia (n = 50) were ellipsoidal or obovate in shape, with mean ± SD dimensions of 6.1 ± 1.1 (4.1 to 9.0) × 2.9 ± 0.6 (1.8 to 4.1) μm, and were usually rounded at each end. On the basis of these morphological characteristics, the isolates were initially identified as Didymella bellidis (Xu et al. 2016; Zou et al. 2020). To confirm the identity, the internal transcribed spacer (ITS), the partial 28S large subunit rDNA (LSU), and the beta-tubulin (TUB) gene of three representative isolates were amplified and sequenced (Chen et al. 2017), respectively. The sequences were deposited in GenBank with accession numbers MN274963, MN274964, MN274965 (ITS); MN274966, MN274967, MN274968 (LSU); and MN274969, MN274970, MN274971 (TUB). Phylogenetic analysis confirmed these isolates to be identical to D. bellidis reference strain D. bellidis CBS 714.85. To fulfill Koch’s postulates, healthy leaves on tea plant twigs (C. sinensis ‘Fuding-Dabai Cha’) were separately inoculated with mycelial plugs from PDA cultures and conidial suspension (1 × 10⁶ conidia/ml, 20 to 30 μl) for three isolates. PDA plugs without mycelia and buffer with no conidia were used as a control. Each treatment contained five replicates. The pathogenicity test was performed three times independently. Brown leaf spots gradually turned into black irregular lesions at 1 day postinoculation; the center of the lesion became darker and necrotic at 5 days postinoculation. The control groups showed no symptoms. The pathogen was reisolated from inoculated samples and identified by morphology and molecular biology. To the best of our knowledge, this is the first report of this fungus causing a tea leaf spot in China and seriously reducing both the productivity and the quality of tea leaves. Our findings will be useful for its management and further research.

Cores from the Lower Cretaceous Tenggeer Formation in the Baiyinchagan Sag of the Erlian Basin present dolomitic mudstones and argillaceous dolostone with white grains and laminae. Thin section, X-ray diffraction (XRD), electron microprobe (EMPA), and scanning electron microscopy (SEM) analyses show that in addition to terrigenous clastics, dolomite, analcime, natrolite, pyrite, pistomesite, fluorite, talc, barite, etc. are abundant. Compared with the conventional lacustrine sediments, these rocks contain highly abundant exhalative textures and structures, such as laminae and banded textures, disseminated textures, mesh-vein structures, breccia structures, and contemporaneous deformations. These types of mineral associations, rock textures and structures are specific and uncommon. Previous works indicate that these rocks are of hydrothermal origin. In this study, we provide supplementary evidence and recognition to support the lacustrine hydrothermal sediment origin and further study the mineral precipitation sequence and formation conditions and processes. With the use of 3D seismic data, the magmatic intrusions, hydrothermal ducts, and hydrothermal vents are first identified on seismic sections. The Ni-Co-Zn and Fe-Mn-(Cu + Ni + Co) × 10 ternary diagrams confirm the hydrothermal origin of these sediments. The Sr/Ba ratio, V / (V + Ni) ratio, oxygen and carbon isotope values of carbonate, pH and EH values suggest anoxic, reducing and alkaline sedimentary conditions. Based on the analysis of fluid inclusions, rock textures and structures, we find that the precipitation of minerals occurred in a specific sequence: pyrite-pistomesite-analcime-natrolite-dolomite. The nature of the magmatic intrusions, the changes in environmental variables and fluid energy, and the flow distance may be the controlling factors of this specific sequence. A mode of lacustrine “white smoker”-type hydrothermal sedimentation is presented in this study: as the hydrothermal fluid sourced from the intermediate-basic magmatic basement enriched in Fe2+, Mg2+, Al3+, Si4+, Ca2+, Na+, and CO32– rose and mixed with cool lake water, ferromagnesian, aluminosilicate, and carbonate minerals formed successively from the ducts to the vicinity of the vents. Pulsing exhalation and overflow formed alternating deposits of hydrothermal sediments and lacustrine mudstones.

With the increasing integration of photovoltaic power into the power system, the reliable photovoltaic power generation prediction is of significant to the security and economics of the power system operation. However, the prediction deviation is unavoidable, therefore this paper presents an interval prediction model for the photovoltaic power generation based on cloud theory. Based on the error analysis of the photovoltaic power prediction, the training samples can be selected to establish the cloud model for each small power generation bin. In this way, the predictive cloud distributions for different predictive power generation can be obtained to generate the prediction intervals at each time slot. To take the photovoltaic power plant in German as example, the proposed model is validated. The results show that the proposed model outperforms the other benchmark method. And the calculation process of the proposed model is simple and short in computation time. The analysis results are expected to be used in the field of power grid dispatching and decision making.

The prediction of electricity sale market is directly related to the balance of electricity supply and demand. The high-precision prediction method of electricity sale market will effectively avoid the imbalance of system supply and demand, and improve the security and economy of the system. In the past, it was difficult to obtain the information of users’ electricity consumption, so the prediction methods of electricity sale market in the past were based on the overall electricity sale. The advantage of this method is that it can get the forecast value of the future electricity sales quickly and intuitively, while the disadvantage is that it fails to consider the electricity development trend of all walks of life that compose the electricity sales in detail.

In recent years, new energy has achieved rapid development in the whole world. However, with the gradual increase in the installed capacity of new energy, because of the uncertainty and volatility of new energy output, new energy has brought many impacts and challenges to the operation of the power system. In order to guarantee the safe and stable operation of the power system, the power system has to provide sufficient flexibility to cope with the volatility and uncertainty of the new energy output. Improving the prediction error accuracy of new energy output can effectively reduce the uncertainty of new energy output, so as to reduce the demand for power system flexibility, reduce the operating cost, and improve the system operation reliability. This paper utilizes the data mining technology to establish the prediction error identification module. Based on the data feature extracted from the wind power prediction input data, the potential abnormal wind power prediction error can be identified, and the original wind power output prediction result can be corrected, so as to improve the predication accuracy of the wind power generation. At the same time, in the prediction and identification process, the wind speed prediction data and historical wind power output data of neighbouring regional wind farms will also be utilized to improve the prediction accuracy of wind farm output in this region. The predicated time scale is 12 hours ahead of time, and the predicted result is the wind power output of the next 12 hours (a predicted resolution of 1 hour, and a total of 12 predicted values).

This paper studies the model of power system adapted to the new energy generation and power market environment. A collaborative planning model of power source considering the uncertainty of the new energy and the power market is proposed. The construction of coal-fired thermal power generating units, wind power generators and transmission lines are considered. At the same time, in view of the uncertainty of wind power generation and electricity market, considering from two perspectives: the randomness of wind power output and the use of geometric Brownian motion to predict electricity price. Finally, the example application of the IEEE 30-bus system shows that the model can effectively coordinate the construction scheme of power grid and power supply.

The Mechanical elastic energy storage (MEES) is a new type of physical energy storage. The energy storage medium is large-scale planar vortex spring (LSPVS), and the energy storage form is mechanical elastic potential energy. Multiple groups of LSPVS are fixed in a single energy storage box, and multiple energy storage boxes are connected in series to form a linked energy storage box group as the energy storage unit of MEES. In the process of energy storage, the torque and inertia of LSPVS change simultaneously. The permanent magnet synchronous motor (PMSM), as the driving device, is required to realize the fast response of torque change and effectively suppress the disturbance of inertia. In this paper, firstly, the mathematical model of linked energy storage box group is established. Secondly, combining with the direct torque control (DTC) model of PMSM and the backstepping control algorithm, the adaptive parameters of torque and inertia control strategy is designed. Finally, the experimental verification shows that the control strategy proposed in this paper has faster torque response and the disturbance of inertia is suppressed simultaneously, so as the energy storage process of MEES can be carried out smoothly and efficiently.

Objective To investigate the effect of NaHS on the expression of connexin 40 (Cx40) and Cx43 in peripheral blood lymphocytes and the release of tumor necrosis factor (TNF-α) and interleukin 6 (IL-6). Methods Six Wistar Kyoto (WKY) rats were selected to collect peripheral blood from the abdominal aorta. Lymphocytes were isolated by density gradient centrifugation, and then divided into control group, concanavalin A (ConA) group and ConA combined with NaHS group. The levels of IL-6 and TNF-α were detected by ELISA; the expression and location of Cx40 and Cx43 in lymphocytes were detected by immunofluorescence staining; the expression frequencies of Cx40 and Cx43 in lymphocytes were detected by flow cytometry; and the protein expression of Cx40 and Cx43 in lymphocytes were detected by Western blot analysis. Results The levels of IL-6 and TNF-α were higher in the ConA group than in the control group, but lower in the ConA combined with NaHS group compared with the ConA group. Immunofluorescence showed that Cx40 was mainly expressed in the cytoplasm and nucleus of lymphocytes, while Cx43 was mainly expressed on the cell membrane. The expression frequencies and protein levels of Cx40 and Cx43 in the lymphocytes were higher in ConA group than in the control group, but lower in the ConA combined with NaHS group compared with the ConA group. Conclusion NaHS can inhibit the release of TNF-α and IL-6 from peripheral blood lymphocytes and down-regulate the expression of Cx40 and Cx43 in lymphocytes.

Based on the coordinated operation of wind power, thermal power and electric vehicles, the paper studies the profit distribution of three-party cooperation based on cooperative game theory. Considering the influence of wind power output prediction deviation on the coordinated dispatching of electric vehicles and thermal power units to wind power, a two-stage optimal scheduling strategy combining day-to-day collaborative planning and intraday correction is proposed. Based on the maximum profit of the alliance, the three-party alliance, two-party alliance and non-alliance optimization scheduling model of the two-phase under the day-to-day period are constructed. The profit results of each optimized scheduling in the day are used as the allocation basis, and the Shapley value, Banzhaf value and Solidarity value allocation strategy are adopted. The three-party alliance profit distribution is carried out, and the core theoretical indicators and the MDP (Modified Disruption Propensity) indicators are set to discriminate the possibility of cooperation and the intensity of cooperation intention under each allocation strategy. The mixed-integer programming technique and CPLEX optimization software are used to simulate the simulation. The results show that the three-party joint model can promote the consumption and development of wind power, and the cooperation under the Shapely value allocation strategy can be established. The cooperation intentions of all members of the alliance are strong.

The development and popularization of electric vehicles (EV) are inseparable from the construction of charging stations, but EV chargers are nonlinear loads, which will bring harmonic pollutions to the power grid. In this case, research on harmonic problems of charging station has practical significance. In this paper, model of a single charger and charging station were established. The variation law of harmonic ratio (HRI), total harmonic distortion (THD) and total demand distortion (TDD) of current with the number of chargers are analyzed under the same charging power or different powers respectively. Then, the mechanism of harmonic counteraction among chargers was analyzed and simulated. The simulation results in this paper showed that: with every charger in the charging station running at the same power, the harmonic current caused by each charger is exactly the same, thus there is no harmonic counteraction; when the operating power of chargers are different, the harmonic amplitude and TDD reduced compared with that under the same power. There exists harmonic counteraction among chargers. In addition., harmonic counteraction is more obvious in higher harmonic orders.

This paper introduces a method for renewable energy accommodation capability calculation based on operation simulations. Load and renewable power output characteristics are analyzed in detail. On this foundation, screening methods for typical scenarios of load and renewable power output in operation simulations are proposed. Finally, combined with the planning of power source and power grid, the renewable energy accommodation capability of Shanxi power grid is evaluated using above method.

Based on the terahertz time-domain reflection spectroscopy, the optical parameters of anhydrous D-glucose polycrystalline, i.e. the refractive index and the absorption coefficient were extracted by using iterative and genetic algorithm, respectively. After comparing and analyzing the two algorithms we had drawn the following conclusions: first, the calculation efficiency of iterative algorithm was improved using the solution of weak absorption approximation as initial values. However, the iterative algorithm was sensitive to the initial values. When the big difference between the initial values and real values existed, the accuracy of optical constants would be affected; Secondly, the genetic algorithm was not insensitive to the initial populations. It ensured the convergence of the algorithm and the population diversity through the design of parameter coding, initial population, genetic manipulation, parameter control and constraint condition. Last, compared with the iterative algorithm, the optical parameters obtained by the genetic algorithm had higher accuracy. Therefore, we suggest that the optical parameters of materials with higher accuracy based on the THz spectroscopy can be obtained by using an intelligent optimization algorithm.

Human naturally analyze and decide a problem from different perspectives, hierarchies, and dimensions, that is referred to as scale transformation (ST). Clustering, as one of the most effective data analysis tools, should support this ST demand. Hence, this paper focuses on the ST problem among clustering analysis especially for decision making. We define the variable-scale dataset based on the rough set theory. What’s more, an algorithm of variable-scale clustering (VSC) is also proposed. A case study shows that compared to the k-modes, the clustering results of the VSC are more available and accessible to decision makers.

Objective To investigate the effects of NO on the expression of connexin 40 (Cx40) on peripheral blood lymphocytes and the levels of TNF-α and IL-6 in the supernatant of culture medium. Methods Peripheral blood lymphocytes of Wistar-Kyoto (WKY) rats were isolated from abdominal aorta and cultured in vitro, and then divided into control group, ConA group and ConA combined with NO group. ELISA was performed to test the levels of TNF-α and IL-6 in the supernatant of culture medium. Immunofluorescence technique was used to detect the expression and location of Cx40 on lymphocytes. Flow cytometry was used to determine the expression frequency of Cx40 on lymphocytes. Western blotting was conducted to examine the protein expression of Cx40 on lymphocytes. Results The levels of IL-6 and TNF-α were higher in the ConA group than in the control group, lower in the ConA combined with NO group than in the ConA group. Immunofluorescence showed that Cx40 was mainly expressed in the cytoplasm and the nucleus. The expression of Cx40 on lymphocytes was higher in the ConA group than in the control group, lower in the ConA combined with NO group than in the ConA group. The expression frequency of Cx40 on lymphocytes was higher in the ConA group than in the control group, lower in the ConA combined with NO group than in the ConA group. The protein expressions of Cx40 and Cx43 on lymphocytes were significantly higher in the ConA group than in the control group, lower in the ConA combined with NO group than in the ConA group. Conclusion NO inhibits the release of TNF-α and IL-6 from lymphocytes and down-regulates the expression of Cx40 on lymphocytes, suggesting that Cx40 on lymphocytes may be involved in the anti-inflammatory effect of NO.

Increasing evidence emphasizes the protective role of Eph receptors in synaptic function in the pathological development of Alzheimer’s disease (AD); however, their roles in the regulation of hippocampal astrocytes remain largely unknown. Here, we directly investigated the function of astroglial EphB2 on synaptic plasticity in APP/PS1 mice. Using cell isolation and transgene technologies, we first isolated hippocampal astrocytes and evaluated the expression levels of ephrinB ligands and EphB receptors. Then, we stereotaxically injected EphB2-Flox-AAV into the hippocampus of GFAP-cre/APP/PS1 mice and further evaluated hippocampal synaptic plasticity and astroglial function. Interestingly, astrocytic EphB2 expression was significantly increased in APP/PS1 mice in contrast to its expression profile in neurons. Moreover, depressing this astroglial EphB2 upregulation enhanced hippocampal synaptic plasticity, which results from harmful D-serine release. These results provide evidence of the different expression profiles and function of EphB2 between astrocytes and neurons in AD pathology.

As one of the key components of railway vehicles, the operation condition of the axle box bearing has a significant effect on traffic safety. The wayside monitoring sound of train axle box bearing is an amplitude modulation and frequency modulation signal with complex train running noise. Although empirical mode decomposition (EMD) and some improved time-frequency algorithms have been proved to be useful in bearing vibration signal processing, it is hard to extract the bearing fault signal from serious trackside acoustic background noises by using those algorithms. Therefore, a kurtosis-optimization-based wavelet packet (KWP) feature extraction algorithm is proposed, as the kurtosis is the key indicator of bearing fault signal in time domain. After beamforming of microphone array, the assessment of KWP is conducted by comparing with exiting algorithms. The test results of 50 fault bearing data indicate that the KWP is more efficient than high frequency resonance technique (HFR) and EMD in an environment where authentic railway noise were present.

Six undescribed C-geranylated flavonoids, including five C-geranylflavanones named as paucatalinones F - J, one C-geranylflavonol named as paucatalinone K, along with seven known geranylated flavanones, were isolated from the fruit peel of Paulownia catalpifolia T. Gong ex D.Y. Hong. Their structures were elucidated distinctly according to their UV, IR, MS, NMR, and CD data. Among them, two compounds were substituted with unusual modified geranyl groups, namely paucatalinone F with an oxygenated cyclogeranyl substituent and paucatalinone H with a terminal pyranoid geranyl substituent. Furthermore, the protective effects on human umbilical vein endothelial cells (HUVECs) injury induced by H2O2 were evaluated, and paucatalinone F showed the most potential activity. The bioactive results suggested that the geranyl substituent may be an important factor for restraining oxidative HUVECs damage and Paulownia C-geranylated flavonoids might have the potential for preventing cardiovascular complications.

Through a three-year field trail, effects of deep plowing time during the fallow period on water storage of 0-200 cm soil before sowing, water consumption of growth period, and growth and development of wheat were investigated. Results demonstrated that soil water storage (SWS) of the fallow period was influenced by deep plowing time, precipitation, and rainfall distribution. With postponing the time of deep plowing in the fallow period, SWS was increased firstly, and then decreased. SWS with deep plowing in early or middle of August was 23.9-45.8 mm more than that with deep plowing in mid-July. It would benefit SWS when more precipitation occurred in the fallow period or more rainfall was distributed in August and September. Deep plowing at a proper time could facilitate SWS, N and P absorption of wheat, and the number of stems before winter and the spike number. The yield of wheat with deep plowing in early or middle August was 3.67%-18.2% higher than that with deep plowing in mid-July, and it was positively correlated with water storage of 0-200 cm soil during the fallow period and SWS of each soil layer during the wheat growth period. However, this correlation coefficient would be weakened by adequate rainfall in spring, the critical growing period for wheat. The time of deep plowing mainly affected the water consumption at soil layer of 60-140 cm during wheat growth. Under current farming conditions of south Shanxi, the increased grain yield of wheat could be achieved by combining the measures of high wheat stubble and wheat straw covering for holding soil water and deep plowing between the Beginning of Autumn (August 6th) and the Limit of Heat (August 21st) for promoting soil water penetration characteristics to improve the number of stems before winter and spike.通过3个年度田间试验,研究了休闲期深翻时间对小麦播前0～200 cm土壤蓄水、生育期耗水及生长发育的影响.结果表明: 休闲期蓄水量受深翻时间、休闲期降雨量和降雨分布的影响.随休闲期深翻时间的推迟,0～200 cm土壤蓄水量先升高后降低,8月上中旬深翻蓄水效果好,较7月中旬深翻多蓄水23.9～45.8 mm;休闲期降雨多或集中在8—9月有利于增加土壤蓄水.休闲期适时深翻可增加土壤蓄水量,促进小麦对氮、磷的吸收,增加冬前茎数和成穗数,8月中上旬深翻较7月中旬深翻增产3.7%～18.2%.产量与休闲期0～200 cm土壤蓄水量、生育期各层土壤耗水量呈正相关,且受春季小麦生育关键期降雨影响较大,降雨多时相关性低,否则相关性高.深翻时间对生育期60～140 cm土层耗水量影响较大.当前耕作条件下,山西南部丘陵旱地在立秋(8月6日)前发挥留高茬和麦秸覆盖的保墒作用,立秋后至处暑(8月21日)期间深翻可提高土壤渗水特性,纳秋雨多蓄水,增加小麦冬前茎数和成穗数,使产量增加.