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Continental shale in China is a key exploration target with regard to unconventional hydrocarbons. Systematic research on the mineral composition, organic geochemistry, and hydrocarbon mobility has been performed in the Da'anzhai (J1dn) lacustrine shale oil reservoirs, clarifying the factors controlling shale oil accumulation. The results suggest that J1dn consists of three sub-members, with an organic-rich interval developed within the second sub-member. Three types of lithological associations have developed within the organic-rich interval: Type 1 represents the interbedding relationship between shale and shell limestone and Type 2 represents shale with intercalated limestone, followed by Type 3. The brittleness index of the J1dn continental organic-rich shale is relatively low. The porosity of the Da'anzhai lacustrine shale ranges between 0.5% and 10.5% (average value of 5.89%). The porosity is predominantly due to inorganic pores, with a small amount being attributable to nanoscale microfractures and organic pores. The average porosity of the shell limestone is only 1.2%, but fractures at the micron and centimeter scales are well developed. The organic matter in the J1dn continental shale is mainly II1–II2, with maturity in the oil generation stage. The average oil saturation of the J1dn continental shale is 3.15%, with most samples having oil saturation of less than 4%. The J1dn continental shale has great exploration potential with regard to shale oil. Type 1 shale oil is affected by multiscale fractures, including bedding fractures, and has the best mobility. The high hydrocarbon generation capacity of lacustrine shale, coupled with the multiscale fractures within shell limestone and shale, is the principal controlling factor for hydrocarbon enrichment. Based on exploration practices, the Type 1 shale association may represent the optimal interval for future shale oil exploration in the Da'anzhai Member. [ABSTRACT FROM AUTHOR]

Organic-rich continental shale, widespread in the Sichuan Basin during the deposition of the Jurassic Dongyuemiao Member (J1d), is considered the next shale hydrocarbon exploration target in southern China. To identify a shale gas sweetspot and reduce exploration risk, it is of great significance to determine the organic matter (OM) enrichment mechanism of J1d shale. In this study, based on sedimentological characteristics and organic matter content, high-resolution major and trace elements were systematically analyzed to demonstrate terrigenous influx, paleoredox, paleosalinity, paleoproductivity, and paleoclimate. The 1st section interval of the J1d 1st submember is dominated by shallow lake subfacies, while the other intervals have the characteristic of semideep to deep lake subfacies. The 1st submember interval of J1d lacustrine shale is characterized by the warmest-humid paleoclimate, strongest weathering degree, highest terrigenous input, moderate paleoproductivity, and paleoredox condition. Within the Dongyuemiao 1st submember, the 4th section interval has the highest paleoproductivity and the most oxygen-deficient condition in bottom water. During the deposition period of the 2nd submember, the sedimentary environment turned to a cold-dry paleoclimate, weak weathering degree, low terrigenous input, low paleosalinity, and high paleoproductivity. Under the background of semideep and deep lake, the terrigenous OM input plays the most critical role in controlling OM enrichment. Moreover, the high primary productivity of lake surface water and the suboxic condition of lake bottom water contribute to the formation of relatively higher TOC lacustrine shale interval in the 4th section of 1st submember. [ABSTRACT FROM AUTHOR]

The centroid of Lie algebra is a basic concept and a necessary tool for studying the structure of Lie algebraic structure. The extended Heisenberg algebra is an important class of solvable Lie algebras. In any Lie algebra, the anti symmetry of Lie operations is an important property of Lie algebra. This article investigates the centroids and structures of 2 n + 2 dimensional extended Heisenberg algebras, where all invertible elements form a group and all elements form a ring. Then, its main research results are extended to infinite dimensional extended Heisenberg algebras. [ABSTRACT FROM AUTHOR]

Background: Thyroxine binding globulin (TBG) deficiency is a rare thyroid disease, mostly caused by genetic mutations and acquired by X-linked recessive inheritance. The clinical features of children with TBG deficiency and their family members were summarised and the Serpina7 gene mutation was analysed, providing a reference for the differentiation of TBG deficiency.Methods: Thyroid function was detected in TBG deficient patients, and genetic analysis was performed using polymerase chain reaction (PCR) and direct DNA sequencing to detect the characteristics of TBG mutants. Using "thyroxine binding globulin, gene and mutation" as keywords, PubMed (biomedical literature database), Web of Science and other databases were searched for relevant studies to collect and summarise relevant information.Results: The TBG (14.7 μg/mL), 70% triiodothyronine (T3) (< 0.3 nmol/L), total T3 (Tr3) (< 0.05 ng/mL) and thyroxine (T4) (14.72 nmol/L) values were lower than normal, while the thyrotropin (TSH) (2.33 uIU/mL), free T3 (FT3) (1.62 pmol/L), and free T4 (FT4) (11.39 pmol/L) values were normal. These values indicate a TBG partially deficient phenotype. Using PCR amplification and direct sequencing of the target gene, a missense mutation in exon 4 of the Serpina7 gene was found in the patient and the father, and the nucleic acid variant was C.909 (exon 4) g > T; the patient was heterozygous and the father was hemizygous. The literature search retrieved a total of 45 studies, most of which were related to mutations in the Serpina7 gene. The mutation locations included exons, introns, enhancers and promoters, with exons the predominant location. A total of 49 variants of the Serpina7 gene were identified.Conclusion: Serpina7 C.909G (P.L303F) is a mutation acquired from the father by X-linked recessive inheritance. The main clinical features of TBG deficiency patients are low serum T4, T3 and TBG levels, normal TSH, FT3 and FT4 levels, and no clinical manifestations. [ABSTRACT FROM AUTHOR]

We define a four-dimensional Lie algebra g in this paper and then prove that this Lie algebra is solvable but not nilpotent. Due to the fact that g is a Lie algebra, ∀ x , y ∈ g , [ x , y ] = − [ y , x ] , that is, the operation [ , ] has anti symmetry. Symmetry is a very important law, and antisymmetry is also a very important law. We studied the structure of Poisson algebras on g using the matrix method. We studied the necessary and sufficient conditions for the automorphism of this class of Lie algebras, and give the decomposition of its automorphism group by A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 , or A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 G 6 , or A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 G 3 , where G i is a commutative subgroup of A u t (g) . We give some subgroups of g's automorphism group and systematically studied the properties of these subgroups. [ABSTRACT FROM AUTHOR]

A facile hydrothermal approach has been successfully adopted to synthesize two‐dimensional Nb2CTx MXene, targeting sodium storage approach in two‐dimensional MXene. As an anode material for sodium‐ion batteries (SIBs), as‐prepared Nb2CTx MXene delivered a stable electrochemical performance of ∼102 mA h g−1 after 500 cycles at a current density of 1.0 A g−1. Further, the full cell comprising of Na3V2(PO4)3@C cathode and Nb2CTx MXene anode also rendered a reversible capacity of 181 mA h g−1 at a current density of 100 mA g−1 after 50 cycles. The good sodium storage could be ascribed to the contribution of hybrid pseudocapacitance, effectively promoted charge storage, unique layered structure and expedited dynamic diffusion of ions. Accordingly, these facts enabled the Nb2CTx MXene to be a promising candidate as an anode material for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Hydrothermal mineral assemblages and related hydrothermally enhanced fracturing are common in the Precambrian Dengying Formation of Central Sichuan Basin. Petrographic and geochemical analyses of core samples show that the hydrothermal dolomite reservoirs of Dengying Formation consist of four main types of pores in the reservoir facies. These include: 1) hydrothermal dissolution vug (or pore), 2) intercrystalline pore, 3) residual inter‐breccia vug (or pore), and 4) enlarged dissolved‐fracture. There are three different fabrics dolomite in hydrothermal dolomite reservoirs, namely, saddle dolomite, fine‐medium dolomite and micritic dolomite. Micritic dolomite is the original lithology of host rock. Saddle dolomite with curved or irregular crystal faces was directly crystallized from hydrothermal fluids (average temperature 192°C). Fine‐medium dolomites are the products of recrystallization of micritic dolomite, resulting in abnormal geochemical characteristics, such as slight depletion of δ18O, significant enrichment of Mn‐Fe and 87Sr/86Sr, and positive Eu anomaly. A model for the distribution of various hydrothermal dolomite reservoir facies is proposed here, which incorporates three fundamental geological controls: 1) extensional tectonics and tectono‐hydrothermal events (i.e., the Xingkai Taphrogenesis of Late Sinian‐Early Cambrian, and Emei Taphrogenesis of Late Permian), 2) hydrothermal fluid storage in clastic rocks with large thickness (e.g., Nanhua System of Chengjiang Formation and part of Doushantuo Formation), and 3) confining bed for hydrothermal fluids (such as, the shale in Qiongzhusi Formation). The supply of hydrothermal fluid is critical. Large basement‐rooted faults and associated grid‐like fracture system may function as the channels for upward migration of hydrothermal fluid flow. The intersection of the above‐mentioned faults (including the conversion fault), especially transtensional sags above negative flower structures on wrench faults can serve as a key target for future hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

Optogenetics is a cell-type specific and high spatial-temporal resolution method that combines genetic encoding of light-sensitive proteins and optical manipulation techniques. Optogenetics technology provides a novel approach for research on cardiac arrhythmia treatment, including pacing, recovering the conduction system, and achieving cardiac resynchronization with precise and low-energy optical control. Photosensitive proteins, which usually act as ion channels, pumps, or receptors, are delivered to target cells, where they respond to light pulses of specific wavelengths, evoke transient flows of transmembrane ion currents, and induce signal transmission. With the development of gene technology, the in vivo efficiency of optogenetics in cardiology has been trialed, and in vitro experiments have been performed to test its potential in cardiac electrophysiology. Challenges for applying optogenetics in large animals and humans include the effectiveness, safety, and long-term expression of photosensitive proteins, unscattered and unattenuated exogenous light stimulation, and the need for implantable miniature light stimulators. Photosensitive proteins, genetic engineering technology, and light equipment are essential for experiments in cardiac optogenetics. Optogenetics may provide an alternative method for evaluating the mechanism of cardiac arrhythmias, testing hypotheses, and treating cardiovascular diseases. [ABSTRACT FROM AUTHOR]

A mesoporous silica loaded with molybdenum phosphide nanoparticles (MoP@MSN) was synthesized using Pluronic F-127 as a hard template. Using the method of XRD and HRTEM, the crystallinity, the phase structure, and the morphologies of the MoP@MSN were investigated. The results showed that the MoP@MSN were composed of nanoflakes with approximately 100 nm. Through the linear sweep voltammetry (LSV), the Tafel slopes of 100 and 341 mV were yielded for MoP@MSN and pure MoP, respectively, meaning that the composite of MSN can significantly improve the conductivity of the products. Meanwhile, the mesoporous MoP@MSN presented excellent electrochemical activity and stability toward hydrogen evolution compared with those of bulk MoP nanoparticles, showing a promising prospect in hydrogen production. [ABSTRACT FROM AUTHOR]

Abstract: Nd2SiO5 ceramics were synthesized and their microwave dielectric properties were investigated. The hexagonal Nd4Si3O12 second phase disappeared and the pure monoclinic Nd2SiO5 phase could be obtained when the molar ratio of Nd2O3/SiO2 was 1:1.05 at 1450°C. The relative density of Nd2SiO5 ceramics increased with increasing temperature. The Nd2SiO5 ceramics sintered at 1500°C exhibited microwave dielectric properties: a dielectric constant (ε r) of 7.94, a quality factor (Q × f) of 38 800GHz and a temperature coefficient of resonant frequency (τ f) of −53ppm/°C. High resonant frequency led to a low dielectric constant and low Q × f value. Nd2SiO5 ceramics have a wide sintering temperature region. They are promising candidate materials for microwave passive components. [Copyright &y& Elsevier]

The Sm2SiO5 ceramics were synthesized and their microwave dielectric properties were investigated. The pure monoclinic Sm2SiO5 phase could be obtained when the molar ratio of Sm2O3/SiO2 was 1:1.05 at 1350°C. A small amount of hexagonal Sm4(SiO4)3 second phase occurred as temperature increased. The relative density of Sm2SiO5 ceramics increased with increasing temperature. The Sm2SiO5 ceramics sintered at 1500°C exhibited microwave dielectric properties: a dielectric constant (εr) of 8.44, a quality factor ( Q × f) of 64 000 GHz, and a temperature coefficient of resonant frequency (τf) of −37 ppm/°C. The Sm2SiO5 ceramics have a wide sintering temperature region and small negative τf values. They are promising candidate materials for millimeter-wave devices. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-encapsulated MnGeO 3 microspheres have been yielded via a facile, scalable and environmentally friendly route. Hydrothermal method was utilized to recrystallize MnGeO 3 particles and form rGO encapsulation. Such rationally designed rGO-encapsulated MnGeO 3 microspheres afforded excellent electrochemical performances, i.e. high first discharge capacity of 1364 mAh g −1 and charge capacity of 810.8 mAh g −1 , and reversible capacity of 624.6 mAh g −1 after 50 cycles at a current density of 200 mA g −1 when they were employed as anode materials for Li ion batteries. These advantageous attributes make rGO-encapsulated MnGeO 3 microspheres the potential anode materials for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: SnO2-doped CaSiO3 ceramics were successfully synthesized by a solid-state method. Effects of different SnO2 additions on the sintering behavior, microstructure and dielectric properties of Ca(Sn1−x Si x )O3 (x=0.5–1.0) ceramics have been investigated. SnO2 improved the densification process and expanded the sintering temperature range effectively. Moreover, Sn4+ substituting for Si4+ sites leads to the emergence of Ca3SnSi2O9 phase, which has a positive effect on the dielectric properties of CaO–SiO2–SnO2 materials, especially the Qf value. The Ca(Sn0.1Si0.9)O3 ceramics sintered at 1375°C possessed good microwave dielectric properties: ε r =7.92, Qf =58,000GHz and τ f =−42ppm/°C. The Ca(Sn0.4Si0.6)O3 ceramics sintered at 1450°C also exhibited good microwave dielectric properties of ε r=9.27, Qf=63,000GHz, and τ f =−52ppm/°C. Thus, they are promising candidate materials for millimeter-wave devices. [Copyright &y& Elsevier]

Optogenetics is an innovative method for precise control of biological function, which makes light manipulation displays more advantages than electric energy because of contactless spatial flexibility and cell-to-cell synchronous communication. The aim of this study was to perform different illumination modes with blue laser to investigate optical control of the mice hearts. In this study, we transfected the light sensitive protein ChR2(H134R) into mouse hearts, which were illuminated with a 473 nm laser on the Langendorff apparatus. We recorded all the signals of electrograms (EGs), epicardium monophasic action potential (MAPs) and light output signals to analyze myocardial electrical activity. EGs and MAP showed that ChR2 expression in the heart can be flexibly controlled by blue light across different illumination sites with corresponding triggered ectopic rhythm. Illumination intensity, pulse duration, and impulse frequency were associated with the light capture rate. Continuous illumination with the threshold intensity on the left ventricle had little influence on sinus rhythm and ventricular electrophysiology. Our results support that flexible control of the cardiac rhythm with optogenetics provides an innovative approach to cardiac research and therapy. • Heart expressed ChR2 can be controlled by blue light. • Light pulses initiated different ectopic rhythm with different illumination sites. • The constant illumination in threshold intensity was safe. • Different mode of light control can be used in cardiac research and therapy. [ABSTRACT FROM AUTHOR]

The poor Uv stability and weak interfacial adhesion are considered as the bottleneck problems for further application of aramid fiber. Herein, a new strategy, Fe 3+ coordination, was reported for aramid fiber to simultaneous improve its Uv resistance and composite interfacial shear strength. Fe 3+ was introduced onto aramid fiber by coordinating with benzimidazole unit of fiber structure. It can reach a doping capacity of as high as 1516ug/g fiber, and the fiber surface is saturatedly covered with Fe 3+ . The chemical structure of Fe 3+ -benzimidazole brings about strong metal-enhanced fluorescence emission effect, which, in turn, greatly raises its Uv stability. Owing to the Fe 3+ coordination, the tensile strength of Fe-coordinated fiber could preserve as high as 96% after Uv irradiation, compared with 73% of untreated fiber. Meanwhile, the introduction of Fe 3+ improves the surface polarity of aramid fiber and consequently leads to the increase of the composite interfacial shear strength by 39%. It is believed that the Fe-coordinated fiber integrates the advantages of easy production, cost-effective and increased Uv stability, as well as high composite interfacial adhesion, and can be used as promising enhancement for the advanced composite material in harsh environment. [ABSTRACT FROM AUTHOR]

Graphene-covered and carbon-encapsulated CoSO 4 nanoparticles (a-C@CoSO 4 @GNs) were first prepared by a facile solution-phase route followed by heat treatment. Subsequently, a-C@CoSO 4 @GNs nanoparticles were utilized as anode materials of Li ion batteries. Such a rationally designed three-dimensional nanostructure could effectively accommodate the volume expansion of CoSO 4 particles during Li-cycling. As a consequence, a-C@CoSO 4 @GNs have delivered remarkable electrochemical performances, i.e., high first discharge capacity (994 mA h g −1 ), prominent cyclic performance of 662.7 mA h g −1 at a current density of 200 mA g −1 and excellent large-current capacity of 497 mA h g −1 at a current density of 1.5 A g −1 after 50 cycles due to catalytically reduced mechanism. More importantly, a-C@CoSO 4 @GNs electrodes possessed outstanding low/high temperature properties, i.e., reversible capacity of 130 mA h g −1 at −20 °C and 1362 mA h g −1 at 60 °C at a current density of 200 mA g −1 . These advantageous attributes make inexpensive, easily available, widespread and non-toxic CoSO 4 promising candidate as anode materials for high-performance lithium-ion batteries under extremely operational environments. [ABSTRACT FROM AUTHOR]