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This study was designed to investigate the role of miR-671-5p in in vitro and in vivo models of ischemic stroke (IS). Middle cerebral artery occlusion and reperfusion (MCAO/R) in C57BL/6 mice as well as oxygen–glucose deprivation and reoxygenation (OGD/R) in a mouse hippocampal HT22 neuron line were used as in vivo and in vitro models of IS injury, respectively. miR-671-5p agomir, miR-671-5p antagomir, pcDNA3.1-NF-κB, and negative controls were transfected into cells using riboFECT CP reagent. miR-671-5p agomir, pcDNA3.1-NF-κB, and negative vectors were administered into MCAO/R mice via intracerebroventricular injection. The results showed that miR-671-5p was significantly downregulated and that miR-671-5p agomir alleviated injury and neuroinflammation induced by ischemic reperfusion. A dual-luciferase reporter assay confirmed that NF-κB is a direct target of miR-671-5p. Reverse experiments showed that miR-671-5p agomir reduced neuroinflammation via suppression of NF-κB expression in both in vitro and in vivo models of IS. Our data suggest that miR-671-5p may be a viable therapeutic target for diminishing neuroinflammation in patients with IS. [ABSTRACT FROM AUTHOR]

Powdery mildew is a very destructive disease that threatens yield and quality of wheat. In the present study, 262 recombinant inbred lines derived from a cross between Zhongmai 578 (ZM578) with moderate resistance to powdery mildew and Jimai 22 (JM22) with high resistance to powdery mildew in the field were used to map powdery mildew resistance loci using the high‐density Illumina iSelect 50K single‐nucleotide polymorphism array. Three quantitative trait loci (QTLs) on chromosomes 2B, 5B, and 5D were identified by inclusive composite interval mapping, designated as QPm.caas‐2BL.1, QPm.caas‐5BL, and QPm.caas‐5DL, respectively, explaining 5.0%–37.0% of the phenotypic variances. The resistance allele of QPm.caas‐5BL was contributed by ZM578, whereas alleles of QPm.caas‐2BL.1 and QPm.caas‐5DL were from JM22. QPm.caas‐2BL.1, detected in all the six experimental environments, was a major and stable QTL. QPm.caas‐5DL was detected in five of the six environments and is likely to be a new QTL for powdery mildew resistance. The kompetitive allele‐specific PCR (KASP) markers Kpm‐2BL and Kpm‐5DL for QPm.caas‐2BL.1 and QPm.caas‐5DL, respectively, were validated in a diverse panel of 287 cultivars. These KASP markers, tightly linked with the QTLs, can be used for marker‐assisted breeding targeting the improvement of powdery mildew resistance in wheat. Core Ideas: Three major quantitative trait loci (QTLs) for powdery mildew resistance were identified in the Zhongmai 578/Jimai 22 population.QPm.caas‐5DL is likely a new QTL, with the resistance allele from Jimai 22.Two kompetitive allele‐specific PCR (KASP) markers for QPm.caas‐2BL.1 and QPm.caas‐5DL were validated in a panel of 287 wheat cultivars. [ABSTRACT FROM AUTHOR]

Background: When frozen pathological results of suspicious peritoneal nodules found in gastric cancer (GC) patients are negative or indeterminant, whether to perform gastrectomy will always be a dilemma for surgeons. This study aimed to facilitate intraoperative surgical decision-making based on frozen section (FS) results and clinicopathological characteristics. Methods: From January 2015 to July 2021, 318 GC patients were enrolled retrospectively. The correlations between frozen and paraffin pathology of peritoneal nodules were examined. Then, predictive factors of positive paraffin section (PS) results were identified, and a nomogram was constructed. The survival significance of gastrectomy was also explored. Results: Of 70 FS-negative patients, 59 (84.3%) had concordant negative PS results, while the PS results of 11 (15.7%) were positive. Forty-six (93.9%) and 3 (6.1%) of 49 patients with indeterminant FS results had positive and negative PS results, respectively. The PS results of 95 FS-positive patients were all positive. A nomogram for predicting positive PS results was developed based on Lauren type, nodule distribution, and CA125. Gastrectomy for FS-negative patients improved survival compared to no gastrectomy (HR 0.26, 95% CI 0.11–0.62; P = 0.0012). Survival benefits for gastrectomy vs. no gastrectomy were not demonstrated in patients with indeterminant (HR 0.74, 95% CI 0.27–2.01; P = 0.53) and positive (HR 0.87, 95% CI 0.43–1.74; P = 0.69) FS results. Conclusions: Gastrectomy can be justified for the treatment of operable GC patients with negative frozen pathological results of peritoneal nodules. For patients with positive and indeterminant frozen pathological results, gastrectomy is not recommended unless it is performed as palliative surgery. [ABSTRACT FROM AUTHOR]

Calcium sulfate or plaster of Paris (POP) is considered as a bone cement with a fast degradation rate, which frequently makes it resorb before the bone defect area is completely filled by new bone. The incorporation of tricalcium silicate (C3S) into POP cement has been proven as a feasible approach to reduce the in vitro degradation rate and improve the in vitro bioactivity of the material. However, the in vivo performance of the POP/C3S composite cement is still unclear. Therefore, the aim of the present study is to assess the biodegradability and osteogenesis of POP/C3S composite cement in comparison with those of POP bone cement. To carry out the in vivo evaluation, POP and POP/C3S cements were implanted into a femoral condyle defect model in rabbits (5 mm diameter × 10 mm length) for 4, 8, and 12 weeks duration. The area of the remaining cement and new bone regeneration in bone defect were investigated and quantitatively measured using radiography, micro-computed tomography, and histological staining. For both cements, no sign of inflammation was observed. POP cement was completely degraded at the 8th week of post-implantation. By contrast, only approximately 50% by volume of POP/C3S composite cement degraded at the 12th week, which allowed a long-term framework for new bone formation. The osteogenic ability of POP/C3S composite cement was significantly superior to that of POP as indicated by the higher mineralization rate and maturity of the newly formed bone around the composite cement. In summary, our findings demonstrated that the in vivo degradation behaviors and osteogenic ability of POP cement could be improved by incorporating C3S in vivo, suggesting that POP/C3S composite cement has potential as a biodegradable cement for bone repair. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s11064-021-03321-1. Correction to: Neurochemical Research (2021) 46:1801-1813 https://doi.org/10.1007/s11064-021-... The original version of the article, Fig. Correction to: miR-671-5p Attenuates Neuroinflammation via Suppressing NF- B Expression in an Acute Ischemic Stroke Model. [Extracted from the article]

In recent years, the industry has demanded high hardness, wear resistance, corrosion resistance, and other properties for critical components made of steel and its alloys. Enhancing the surface properties of a part by applying modification techniques to its surface is considered to be an economical and efficient method. Laser hardening, as a new surface modification technology, has received more and more attention due to its high hardening efficiency, fast cooling rate, and excellent surface properties. Laser hardening technology has good application prospects in surface modification, and significant progress has been made in the exploration of laser hardening strengthening mechanisms, optimization of process parameters, high-quality preparation of hardened layers, and theoretical simulation. However, some problems need to be addressed in the practical application of the technology. This paper reviews the research progress of the laser surface hardening process for steel and its alloys, including numerical investigation, process optimization, hardening performance analysis, and external field-assisted laser hardening technology. It also discusses the problems and challenges faced by the technology and gives an outlook on its development trend. [ABSTRACT FROM AUTHOR]

The southwest vortex (SWV) is a critical weather system in China, but our knowledge of this system remains incomplete. Here, we investigate the cloud properties in the SWV. First, we search for the SWVs with time steps and center locations that are consistent between the SWV yearbook and ERA-Interim reanalysis data. Second, we supplement these SWVs' life spans and movement paths. Third, we relocate the Fengyun (FY) satellite FY-4A cloud retrievals in the 10° × 10° region centered on each SWV and analyze the cloud occurrence frequency (COF), cloud-top height (CTH), and cloud optical thickness (COT). A distribution mode of cloud types is summarized from the COFs, with water clouds, supercooled clouds, mixed clouds, ice clouds, cirrus clouds, and overlap clouds occurring sequentially from west to east. The CTH probability density (PD) distribution features a significant north–south difference. In addition, the COT PD distributions exhibit a common trend: with increasing COT, the PD increases rapidly and then slowly before peaking, whereupon the PD decreases abruptly. From spring to summer, the region with the highest convective COF shifts from the northeast to the northwest, and an east–west gradient of the convective COF appears in autumn and winter. Furthermore, we investigate the cloud properties during SWV-related heavy rainfall. Heavy rain occurs mainly in the west of the SWV, and convective clouds are mainly in the northwest, partly in the southwest and near the SWV center. The average CTH in heavy rainfall is generally higher than 6 km, and the average COT is greater than 20. Significance Statement: The southwest vortex (SWV) is an important weather system in China. However, we do not yet comprehensively know this weather system. The cloud properties can indicate the structures of weather systems and are key parameters in numerical weather prediction (NWP) models. Thus, investigating cloud properties is necessary and meaningful to understand the SWV and accurately predict SWV-related precipitation in NWP models. In this paper, a typical distribution mode of six cloud types in the SWV is summarized from the cloud occurrence frequency, and the distribution features of convective clouds, cloud-top height, and cloud optical thickness in the SWV are analyzed. Furthermore, the cloud properties in SWV-related heavy rain are also studied. [ABSTRACT FROM AUTHOR]

Chlorite is beneficial to the preservation of primary pores, and its formation mechanism in marine sandstone has been widely reported. However, few studies have focused on the genetic mechanism of various types of chlorite in lacustrine deltaic sandstone. Therefore, the occurrence, diagenetic time and origin of chlorite in Xujiahe tight sandstone were investigated using microscopic images and mineralogical chemical analysis, and three stages of chlorite were identified, namely, grain-coating (Ch1), pore-lining (Ch2), and pore-filling (Ch3) chlorite, which belong to the Fe chlorite, Al chlorite and transitional types, respectively. The variations in morphology and chemical composition reflect differences in the sources and formation mechanisms. Chlorite sandstones are mainly distributed in the underwater distributary channel, which has strong hydrodynamic conditions. The formation of Ch1 is controlled by the sedimentary environment and flocculation. Salinity differences resulted in a larger amount of flocculation deposits in the estuaries during the syngenetic period. In the shallow burial stage, the clay coating underwent in situ transformation under thermal impacts and formed the Ch1. Xujiahe sandstones experienced complex diagenetic processes, which include early compaction, three stages of chlorite cementation, two stages of quartz precipitation, dissolution and two stages of carbonate cementation. Organic acid dissolution of volcanic rock fragments, phyllite, and biotite likely supplied sufficient Fe2+ for the growth of Ch2 in a relatively closed diagenetic system. As the pore water became weakly alkaline, diagenetic fluid migration originating from the clay mineral transformation in mudstone mainly provided Fe2+ and Mg2+ for Ch3 growth in sandstones. Chlorite is considered to have "composite" impacts on deep tight sandstones, with grain-coating and pore-lining chlorites protecting the primary pores by restricting the silica supply and occupying potential quartz nucleation sites; however, grain-coating chlorite caused throat obstruction or even closure under strong mechanical compaction, which reduced the permeability of the reservoir. • Three different types of chlorite have been found in the Xujiahe tight sandstones. • It has been clear that the formation time of chlorite and the paragenetic sequence of authigenic minerals. • The origin and formation mechanism of authigenic chlorite in three types have been investigated. • We considerd that authigenic chlorite has a "composite" impact on deep tight sandstone: preserve primary porosity but reduce the permeability. [ABSTRACT FROM AUTHOR]

A lithium–sulfur battery, a potential next-generation secondary battery, is affected by poor conductivity of sulfur and the dissolution of intermediate polysulfides. Here we report a lithium–sulfur battery with ultrahigh sulfur loading and excellent cycling stability using porous graphitic carbon (PGC) as a high-conductivity carrier of sulfur and carbon fiber with crisscross conductive framework as an electric attachment site of sulfur. PGC is fabricated through a simple and environmentally friendly synthesis process involving high-temperature graphitization in a N2 atmosphere followed by an annealing process in air. Due to the presence of porous graphitic structure, with C–O termination groups, PGC endows the lithium–sulfur battery system with excellent cycling performance. The lithium–sulfur battery cathode constructed by PGC with a sulfur loading of 2.5 mg cm−2 still retains a high specific capacity of 734.4 mA h g−1 after 200 cycles. Meanwhile, an ultrahigh sulfur loading of 12.8 mg cm−2 for a CR2025 coin cell is achieved, which is the highest sulfur loading reported in the literature for the coin cell. The ultrahigh sulfur loading cell also shows good electrochemical properties, profiting from the mesopores terminated with C–O groups, high specific surface area of 1129.9 m2 g−1 and high-conductivity graphitic structure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hollow V2O5 spheres constructed from plate-like particles were synthesized and used as supercapacitor electrodes in a solution of 5M LiNO3. [•] These materials exhibited a tremendous pseudocapacitance effect with a high capacitance of 479Fg−1 at 5mVs−1. [•] The hollow V2O5 spheres was coated with PPy exhibited the capacitances of 559Fg−1 at 3Ag−1 by GCD and 566Fg−1 at 5mVs−1 by CV, respectively. [Copyright &y& Elsevier]

[Display omitted] • A strategy to fabricate conductive SiO 2 @Ga core–shell microparticles is developed. • Maximizing catalytically active surface gallium for electrocatalysis of Li 2 S x. • The addition of microparticles promote the ion transfer kinetics of the electrodes. • A mechanism of conductive electron-given-surface and fast Li+ transport is proposed. • Li-S batteries with high sulfur loading and high specific capacity are achieved. A novel silica@gallium core–shell structure is designed to maximize catalytically active surface gallium for highly efficient electrocatalysis of lithium polysulfides in lithium-sulfur batteries. The fabricated SiO 2 @Ga/S cathode battery exhibits a high reversible capacity of 927.1 mAh g−1 at 0.75C and excellent cycling stability with a capacity retention rate of 85.97% for 600 cycles. When the sulfur mass loading is up to 6.5 mg cm−2, the battery displays a high discharge capacity of ~ 4.145 mAh cm−2 with high Coulombic efficiency of 85.04% after 200 cycles. Finally, a mechanism that the highly conductive electron-given-surface of liquid metal Ga shell on the surface of SiO 2 in the thick electrodes for reversible electrocatalysis of lithium polysulfides in lithium-sulfur batteries is proposed. [ABSTRACT FROM AUTHOR]

Key message: We fine-mapped QBp.caas-3BL for black point resistance in an interval of 1.7 Mb containing five high-confidence annotated genes and developed a KASP marker suitable for selection of QBp.caas-3BL. Wheat black point, which occurs in most wheat-growing regions of the world, is detrimental to grain appearance, processing and nutrient quality. Mining and characterization of genetic loci for black point resistance are helpful for breeding resistant wheat cultivars. We previously identified a major QTL QBp.caas-3BL in a recombinant inbred line (RIL) population of Linmai 2/Zhong 892 across five environments. Here we confirmed the QTL in two additional environments. The genetic region of QBp.caas-3BL was enriched with newly developed markers. Using four sets of near isogenic lines, QBp.caas-3BL was narrowed down to a physical interval of approximately 1.7 Mb, including five annotated genes according to IWGSC reference genome. TraesCS3B02G404300, TraesCS3B02G404600 and TraesCS3B02G404700 were predicted as candidate genes based on the analyses of sequence polymorphisms and differential expression. We also converted a SNP of TraesCS3B02G404700 into a breeding-applicable KASP marker and verified its efficacy for marker-assisted breeding in a panel of germplasm. The findings not only lay a foundation for map-based cloning of QBp.caas-3BL but also provide a useful marker for selection of resistant cultivars genotypes in wheat breeding. [ABSTRACT FROM AUTHOR]

• A novel method for defouling fouled outdoor coils in ASHPs has been developed. • The method is based on three directly measurable operating temperatures. • Further field studies to verify the method's applicability were carried out. • The method provided an accurate and convenient way for defouling initiation. Air source heat pumps (ASHPs) have been widely used for space cooling in recent years. When a space cooling ASHP unit is operated in an ambience with poor air quality, fouling of its outdoor coil can be easily built up, leading to a significant drop in the operating efficiency and output cooling capacity of the ASHP unit. Therefore, as a follow-up to a previous related study, a study to develop a novel defouling initiation method for the fouled outdoor coil in a space cooling ASHP unit based on its measurable characteristic ambient and operating temperatures has been carried out and the study results are reported in this paper. Firstly, a characteristic parameter of TTT, which can be evaluated based on ambient air Temperature, outdoor coil metal surface Temperature and outdoor coil outlet air Temperature, is defined. Secondly, the development of the novel defouling initiation method is detailed. Finally, further field comparative studies using the developed novel defouling initiation method have been carried out, and the study results demonstrated that the novel defouling initiation method can provide an accurate and convenient way to initiate defouling of the fouled outdoor coil in an ASHP unit at a reasonable defouling frequency to ensure its best possible operating performances. [ABSTRACT FROM AUTHOR]

Abstract To better understand gas migration and accumulation in tight sandstone reservoirs, we conducted an integrated petrographic and geochemical analysis of hydrocarbon and aqueous fluid inclusions. This analysis was combined with the burial and multistage hydrocarbon charging histories of the reservoir. The variability in the types of hydrocarbon inclusions in the tight sandstone reservoirs can be mapped to identify phase fractionation during burial and migration. The oil-bearing inclusions resulted from the heterogeneous capture of oil generated during the first hydrocarbon charging period, when the sandstones had not yet reached tight reservoir conditions. The gas-bearing inclusions in the tight sandstone reservoirs formed during the phase fractionation of dissolved and free gas due to unstable pressure conditions. The gas-bearing inclusions are characterized by a varying vapor volume fraction (φ vap). A higher proportion of gas-bearing inclusions with φ vap < 25% was observed near the source rock with TOC content >1.2%. In contrast, in structural highs, a higher proportion of gas-water inclusions with φ vap > 25% was observed, demonstrating that phase fractionation occurred during migration. The GOI data suggest that the dissolved gas migration mainly occurred in the reservoir near the source rock with TOC content >1.2%. The subsequent free gas separation in relation to upward migration and strata uplift caused free gas to migrate farther into the tight sandstone reservoir. Additionally, the gases displayed benzene/n-hexane ratio, methane and ethane δ13C values increasing initially, then decreasing along the migration pathway, recording the phase state evolution of the natural gas during the burial history of the reservoirs. Highlights • The paleopressure evolution has been reconstructed. • The geochemical fractionation effects in high and low surplus pressure zone are investigated. • Phase fractionation during the burial history is revealed by fluid inclusion petrography and microthermometry. [ABSTRACT FROM AUTHOR]

Highlights • Impacts of fouling and ambient temperature on ASHP's performances were studied. • Increased fouling level and ambient air temperature led to poorer performances. • An equivalent temperature rise due to fouling was proposed and evaluated. • An improved simulated fouling approach was experimentally validated. Abstract Air source heat pumps (ASHPs) have been widely used for providing buildings with heating in winter and cooling in summer. In certain locations, with an increased level of air pollutions, fouling of the outdoor coil in a space cooling ASHP unit may appear, which affects the operating performances of the ASHP unit. Furthermore, the operating performances of an ASHP unit can also be affected by ambient air temperature (T a). In this paper, a field study on the effects of outdoor coil fouling at different T a on the operating performances of a field space cooling ASHP unit is presented. The study results demonstrated that the operating performances of the field ASHP unit were significantly affected by the changes in both T a and percentage of fouled outdoor coil surface (PFOCS). For example, at T a = 30 °C, the variation in PFOCS from 0 to 100% led to a reduction in COP for the field ASHP unit from 2.7 to 2.0. At a fixed PFOCS of 60%, the changes in T a from 26 to 33 °C resulted in a reduction in COP from 2.6 to 2.1. In order to more conveniently investigate the combined impacts of fouling on the operating performances of an ASHP unit at different T a , an equivalent ambient air temperature rise (ETR) was proposed. Based on the measured and evaluated operating parameters of the field ASHP unit at different T a and PFOCS values, ETR values at 0 - 40%, 40 - 60%, 60 - 100% and 0 - 100% PFOCS ranges were evaluated. These ETR values implied that defouling of a fouled outdoor coil may be initiated when PFOCS was at 40 - 60%. With the ETR values for the full PFOCS range of 0 - 100%, the impact of full fouling on the operating performances of an ASHP unit may be evaluated as if it was operated with a clean outdoor coil but at an equivalent ambient air temperature of T a + ETR. [ABSTRACT FROM AUTHOR]

Abstract The Lower Cretaceous Yingcheng Formation in the Longfengshan sag (Songliao Basin, China) represents a typical tight sandstone reservoir that hosts large accumulations of hydrocarbons. The lacustrine sandstones mainly reflect gravity flow deposits making up various lithofacies displaying varying degrees of heterogeneity. This study reports on the links among gravity flow type, diagenetic overprinting and pore-throat characteristics that control reservoir quality. Core observations, especially grain size variations and related sedimentary structures are used to differentiate types of gravity flows. Microscopic observations, cathodoluminescence, scanning electron microscopy, pressure-controlled mercury injection tests and rate-controlled mercury injection tests are used to determine the mineralogy, sedimentary composition and pore-throat characteristics of the tight sandstones. In the study area, the gravity flows are divided into muddy debris flows, sandy debris flows, high-density turbidity flows, low-density turbidity flows and mud density flows. The petrophysical properties of these different gravity flow sediments reflect a range of permeability and porosity characteristics. Because of their mud-dominated textures and related weak compressive strength, mud density flows and muddy debris flows become ineffective as reservoirs during burial. In contrast, for approximately similar burial depths, turbidites and sandy debris flows show better reservoir quality. However, reservoir units with high porosities still possess considerable heterogeneity; this is especially true of some sandy debris flows that possess large amounts of secondary pores but which are not charged with hydrocarbons. In particular, in some poorly sorted sandy debris flows that are characterized by high contents of fine-grained matrix, some of the pore throats are blocked by matrix material. Moreover, the dissolution of feldspars and volcanic debris led to the formation of authigenic clays and quartz, which preferentially developed in pore throats with small radii. This process significantly reduced permeability. Overall, the permeabilities of the sandy debris flows are generally lower than those of the turbidites. Due to their relatively large-radius pore throats, turbidites can be categorized as potential effective hydrocarbon reservoirs in the study area. This research provides significant insights into the characteristics of pore throats within tight reservoirs consisting of gravity flow sediments in lacustrine basinal settings. Highlights • Gravity flow sediments have been categorized based on sediment support mechanism, flow state and sediment characteristics. • Pore-throat characteristics of different kind of gravity flow sediments are addressed. • Depositional texture and host rock buffered diagenesis are the main factors controlling reservoir quality. • Turbidites have the highest reservoir potential. [ABSTRACT FROM AUTHOR]

Highlights • The TEPS defrosting initiation strategy was applied to mild and humid regions. • Five short-term and two long-term field test cases were conducted. • The TEPS defrosting initiation strategy was compared to the TT initiation strategy. • The use of TEPS strategy led to more accurate and reliable defrosting initiation. • The use of TEPS strategy led to better operating performances of ASHPs. Abstract A defrosting initiation strategy based on tube-encircled photoelectric sensors (TEPS) was previously proven effective for enhancing the frosting-defrosting performances of air source heat pumps (ASHPs) in cold and dry regions. To verify its applicability to, and evaluate the energy-saving potential when using the TEPS-based strategy in mild and humid regions, field tests were conducted in Guiyang City, China, where the outdoor averaged air temperature and relative humidity were 4.5 °C and 80% in winter, respectively. Two ASHPs of the same-make, one with the TEPS-based strategy and the other with the commonly used temperature-time (TT) strategy, were tested. Totally, seven test cases were organised. Cases 1–5 were for short-term tests to verify the technical feasibility of TEPS-based strategy by comparing the defrosting accuracy of the two strategies. Cases 6–7 were for long-term tests to validate the reliability and effectiveness of the TEPS-based strategy by comparing two ASHPs' operating performances. The test results demonstrated that the use of TEPS-based strategy in mild and humid regions can initiate defrosting more accurately, reliably and efficiently, and thus improve the COP and heating capacity by 11.3% and 12.1%, respectively, compared to the use of the TT strategy. Therefore, it was proven that the TEPS-based strategy was more effective for the ASHPs used in mild and humid regions, for a more accurate defrosting initiation and higher energy efficiency. [ABSTRACT FROM AUTHOR]

The practical applications of lithium sulfur batteries have been greatly restricted by the polysulfide shuttle effect and non-conductivity of sulfur. Here, we report a nickel-catalyzed carbonization method to synthesize three-dimensional (3D) nickel@N-doped carbon-nanotube (CNT) foams for lithium-sulfur batteries. The corresponding carbon/sulfur cathode with a high sulfur loading of 3.71 mg cm−2 possesses a high initial capacity of 855.6 mAh g−1 at 135 mA g−1 and good cyclic stability with a low fading rate of 0.153% per cycle for 100 cycles at 270 mA g−1. The growth of carbon thin layers on the nickel nanoparticles results in the encapsulation of the nanoparticles in the CNTs, which makes the carbon forms highly conductive and prevents the metal nanoparticles from being oxidized by polysulfides. The high conductivity is favorable for the electron transfer between polysulfides and carbon electrode. Moreover, the doped nitrogen atoms on the CNTs have strong chemical adsorption ability for polysulfides, accelerating redox reaction of polysulfides on the carbon electrode (i.e., suppressing the shuttle effect). These unique structural characteristics well explain the excellent electrochemical performance of the assembled batteries. It is believed that the fabricated carbon foam is a promising material for high sulfur-loading lithium-sulfur battery. [Display omitted] • Encapsulates carbon-coated Ni metal nanoparticles in N-doped carbon nanotube. • 3D highly conductive network and strongly chemisorptionto polysulfides. • Stable cycle performance of lithium-sulfur battery under high sulfur loading. [ABSTRACT FROM AUTHOR]

To improve the defrosting accuracy of air source heat pumps (ASHPs), this paper proposes a novel defrosting control method by applying tube encircled photoelectric sensors (TEPSs). A field test was conducted for two heating seasons in Beijing, China, to verify the feasibility and practicality of the novel TEPS method. The test results revealed that irrespective of the environmental conditions, the TEPS method can initiate defrosting in similar situations: most of the heat exchanger surface had been covered by frost; the compressor suction temperature decreased by ~9 °C; the compressor discharge temperature increased by ~16 °C; and the heating capacity decreased by ~30%. Furthermore, the TEPS method was verified to make more accurate and more reasonable defrosting decisions than the traditional T-T method under both frosting and non-frosting conditions. The results indicate that the TEPS method is a competitive defrosting control method that can be used for ASHPs. [ABSTRACT FROM AUTHOR]

Sparse representation classification, as one of the state-of-the-art classification methods, has been widely studied and successfully applied in face recognition since it was proposed by Wright et al. In this study, we proposed a method to generate virtual available facial images and modified the well-known linear regression classification (LRC) and collaborative representation based classification (CRC) for face recognition. The new method integrates the original and virtual symmetry facial images to form a training sample set of large size. Experimental results show that the proposed method can achieve better performance than most of the competitive face recognition methods, e.g. LRC, CRC, INNC, SRC, RCR, RRC and the method in Xu et al. (2014). This promising performance is mainly attributed to the fact that the sample combination scheme used in the new method can exploit limited original training samples to produce a large number of available training samples and to convey sufficient variations of the original training samples. [ABSTRACT FROM AUTHOR]

To improve the defrosting accuracy and the energy efficiency of the air-source heat pump (ASHP) under frosting and defrosting conditions, a novel Temperature–Humidity–Time (T–H–T) defrosting control method, based on a frosting map for the ASHP unit, is proposed in this paper. A field test was conducted for two heating seasons, to verify the feasibility and applicability of the T–H–T method. The advantages of the T–H–T method, compared to the conventional Temperature–Time (T–T) defrosting control method, are presented. In total, eight cases are shown in this paper. Cases 1 to 4 were chosen to reveal the T–H–T performance under different frosting conditions. It was found that no matter what kind of frosting conditions, defrosting was always initiated in a similar situation: ∼90% of the outdoor coil surface was covered by frost; the temperature difference between the compressor suction and discharge increased by ∼20%; and the heating capacity decreased by ∼30%. These results indicate that the T–H–T method can make an accurate decision under different frosting conditions. Cases 5a, 5b and Cases 6a, 6b were two groups of cases to compare the advantages of the T–H–T method against the conventional T–T method. Cases 5a and 5b were chosen for the non-frosting condition. It was found that the T–T method initiated the defrosting operation 31 times within 24 h. However, none of the defrosting operations was conducted for the T–H–T method. Cases 6a and 6b were chosen to compare these two methods under consecutive and variable frosting conditions. For the T–T method, 63% of the defrosting processes were found to be executed under conditions where defrosting was not necessary. However, for the T–H–T method, all the defrosting controls were found to be accurate and reasonable. These results indicated that the novel T–H–T method is suitable for the defrosting control of the ASHP, and has a more competitive performance than the conventional T–T method. [ABSTRACT FROM AUTHOR]

Classification using the l-norm-based representation is usually computationally efficient and is able to obtain high accuracy in the recognition of faces. Among l-norm-based representation methods, linear regression classification (LRC) and collaborative representation classification (CRC) have been widely used. LRC and CRC produce residuals in very different ways, but they both use residuals to perform classification. Therefore, by combining the residuals of these two methods, better performance for face recognition can be achieved. In this paper, a simple weighted sum based fusion scheme is proposed to integrate LRC and CRC for more accurate recognition of faces. The rationale of the proposed method is analyzed. Face recognition experiments illustrate that the proposed method outperforms LRC and CRC. [ABSTRACT FROM AUTHOR]

The organic-rich shales of the upper Permian Dalong Formation in the middle Yangtze area are considered an important shale gas exploration horizon. However, the origin of siliceous matter and the mechanism of organic matter enrichment are still controversial. Based on geochemical data, we studied the provenance, paleoclimate, paleoenvironment, primary productivity and hydrological conditions of the Dalong Formation in western Hubei Province and discussed the mechanism of organic matter enrichment. The shales of the Dalong Formation can be divided into two units, organic-rich and organic-lean shales, with average TOC contents of 5.81 wt% and 0.45 wt%, respectively. The western Hubei Basin was a strongly restricted basin during deposition, and the provenance of the Dalong Formation had a continental margin sedimentary background, mainly from mixed felsic and basic sources. Terrigenous clastic quartz, biological quartz and hydrothermal quartz are recognized in the shales of the Dalong Formation. Based on U, V, and Mo concentrations and V/(V + Ni) ratios, the organic-rich shales were deposited in anoxic-sulfurized conditions. In contrast, the organic-lean shales were deposited under oxic-suboxic conditions. The Dalong Formation had moderate to high primary productivity and controls on the redox conditions in the basin. The decrease in primary productivity in organic-lean shales may be related to the transition from a warm and humid climate to a hot and dry climate. The sedimentary model shows that the formation of organic-rich siliceous rocks in the Dalong Formation was controlled by primary productivity. The decrease in primary productivity driven by the hot and dry climate in the latest Permian is the main factor controlling the enrichment of organic matter and the formation of bioquartz. • Dalong shale contains terrigenous clastic quartz, biological quartz and hydrothermal quartz. • The anoxic-sulfurized water were widely distributed on the organic-rich shales deposited. • Hot and dry climate caused the reducing primary productivity. • Organic matter enrichment controlled mainly by the primary productivity. [ABSTRACT FROM AUTHOR]

• A new method to fabricate 3D porous sulfur/gallium hybrid materials is developed. • The 3D porous sulfur/gallium hybrid materials increase the electrical and ion conductivity of the cathode. • The 3D porous sulfur/gallium hybrid materials promote the activation of the electrodes. • The surface of liquid metal Ga promote the redox reaction of lithium polysulfides due to its strong electrocatalytic effect. • Li-S batteries with high sulfur loading, long cycling and high specific capacity are achieved. Lithium–sulfur battery has long been considered as the best choice for the next generation secondary battery. However, the intrinsic insulativity of sulfur and the polysulfide shuttle effect have been the key problems that hinder the commercialization of lithium sulfur batteries. Here, using a facile shearing implement assists thermal synthesis process, in which liquid metal gallium and sulfur (mass ratio1:10) are the only reactants, we create a 3D porous sulfur/gallium hybrid materials (S/Ga). Micro/nanometer liquid metal gallium particles embed in the porous sulfur. The S/Ga cathode lithium cell exhibits a high Coulombic efficiencies of 98.7%, and high specific capacities of 1044 mAh g−1 after 100 cycles at 1.0 mA cm−2, and good cyclic stability. During first cycle discharge process of the S/Ga cathode, the sulfur reduces to Li 2 S 8 and dissolves in the electrolyte, then the liquid metal Ga has an intimate electrical contact with conductive carbon substrates. Electrons are easily transferred to high conductive liquid metal Ga. Due to the electron abundance on Ga surface, it shows an electrocatalytic effect for the conversion of soluble lithium polysulfides (Li 2 S 4-8) to Li 2 S 2 /Li 2 S, thus improving S utilization and cyclic stability. Image, graphical abstract [ABSTRACT FROM AUTHOR]