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The current work deals with the mechanical buckling behavior of saturated porous toroidal shell segments sandwiched by piezoelectric actuator layers. Material properties of the porous shells with nonuniform distributed porosities are assumed to vary as a specific function of the thickness and porosity parameters. The nonlinear equations of the sandwich toroidal shell having either positive or negative Gaussian curvature are obtained on the basis of Biot's poroelasticity theory. The energy method as the minimum potential energy principle is applied to derive the governing equations of the sandwich shells. The buckling equations of the piezo-porous sandwich shells under various types of mechanical loading are established by employing the adjacent equilibrium criterion. The governing equations as a set of the coupled partial differential equations are solved using an analytical method including the Airy stress function. Closed-form solutions are derived for shallow segments of the sandwich toroidal shell with positive/negative Gaussian curvature under lateral pressure, axial compression, and hydrostatic pressure loadings. Novel numerical results are presented in this work to show the effects of important factors such as the piezoelectric layer thickness, applied voltage, shell geometrical ratio, and variation of the porosity coefficient on the buckling behavior of these structures. [ABSTRACT FROM AUTHOR]

The Pd‐catalyzed vinylation reactions of aryl iodides using 1,2‐dibromoethane is developed for the synthesis of styrenes and stilbenes. In these reactions, vinyl bromide is generated from 1,2‐dibromoethane and then undergoes reductive cross‐coupling with aryl iodides, affording styrene products. Under slightly modified reaction conditions, styrenes can continue reacting with vinyl bromide to form E‐stilbenes, which provides a one‐pot synthetic method for stilbenes. Alcohols, including iso‐propanol and methanol, are employed as the reductant in these reductive cross‐coupling reactions. [ABSTRACT FROM AUTHOR]

A facile and efficient method has been developed for the synthesis of fluorenes by Pd-catalyzed C–H alkylation of biphenyl-2-yl trifluoromethanesulfonates. The trifluoromethanesulfonates are more readily available and more environmentally benign than biphenyl iodides, and are advantageous substrates for traceless directing-group-assisted C–H activation. The reaction generates C,C-palladacycles as the key intermediates that form two C(sp2)–C(sp3) bonds through reaction with CH2 Br2. The reaction tolerates various functional groups, permitting easy access to a range of fluorene derivatives. [ABSTRACT FROM AUTHOR]

The mining industry production is an important pillar industry in China, while its extensive production activities have led to several ecological and environmental problems. Earth observation technology using high-resolution satellite imagery can help us efficiently obtain information on surface elements, surveying and monitoring various land occupation issues arising from open-pit mining production activities. Conventional pixel-based interpretation methods for high-resolution remote sensing images are restricted by "salt and pepper" noise caused by environmental factors, making it difficult to meet increasing requirements for monitoring accuracy. With the Jingxiang phosphorus mining area in Jingmen Hubei Province as the studied area, this paper uses a multi-scale segmentation algorithm to extract large-scale main characteristic information using a layered mask method based on the hierarchical structure of the image object. The remaining characteristic elements were classified and extracted in combination with the random forest model and characteristic factors to obtain land occupation information related mining industry production, which was compared with the results of the Classification and Regression Tree model. 23 characteristic factors in three aspects were selected, including spectral, geometric and texture characteristics. The methods employed in this study achieved 86% and 0.78 respectively in overall extraction accuracy analysis and the Kappa coefficient analysis, compared to 79% and 0.68 using the conventional method. [ABSTRACT FROM AUTHOR]

Objective: To prove microtubule associated serine/threonine kinase 3 (MAST3) gene is associated with neurodevelopmental diseases (NDD) and the genotype-phenotype correlation. Methods: Trio exome sequencing (trio ES) was performed on four NDD trios. Bioinformatic analysis was conducted based on large-scale genome sequencing data and human brain transcriptomic data. Further in vivo zebrafish studies were performed. Results: In our study, we identified four de novo MAST3 variants (NM_015016.1: c.302C > T:p.Ser101Phe; c.311C > T:p.Ser104Leu; c.1543G > A:p.Gly515Ser; and c.1547T > C:p.Leu516Pro) in four patients with developmental and epileptic encephalopathy (DEE) separately. Clinical heterogeneities were observed in patients carrying variants in domain of unknown function (DUF) and serine-threonine kinase (STK) domain separately. Using the published large-scale exome sequencing data, higher CADD scores of missense variants in DUF domain were found in NDD cohort compared with gnomAD database. In addition, we obtained an excess of missense variants in DUF domain when compared autistic spectrum disorder (ASD) cohort with gnomAD database, similarly an excess of missense variants in STK domain when compared DEE cohort with gnomAD database. Based on Brainspan datasets, we showed that MAST3 expression was significantly upregulated in ASD and DEE-related brain regions and was functionally linked with DEE genes. In zebrafish model, abnormal morphology of central nervous system was observed in mast3a/b crispants. Conclusion: Our results support the possibility that MAST3 is a novel gene associated with NDD which could expand the genetic spectrum for NDD. The genotype-phenotype correlation may contribute to future genetic counseling. [ABSTRACT FROM AUTHOR]

This paper is concerned with the issue of finite-time H ∞ load frequency control for power systems with actuator faults. Concerning various disturbances, the actuator fault is modeled by a homogeneous Markov chain. The aperiodic sampling data controller is designed to alleviate the conservatism of attained results. Based on a new piecewise Lyapunov functional, some novel sufficient criteria are established, and the resulting power system is stochastic finite-time bounded. Finally, a single-area power system is adjusted to verify the effectiveness of the attained results. [ABSTRACT FROM AUTHOR]

An efficient protocol for the palladium-catalyzed cross-coupling reaction of 2-iodobiphenyls with biphenylene has been developed through C–H activation. The reaction provides a simple and efficient method for the synthesis of unsymmetrically substituted tetra-phenylenes. [ABSTRACT FROM AUTHOR]

Summary: With the continuous improvement of the national design standards of urban road lighting system, the intelligent, automatic, and remote management of urban street lighting system by using modern computer technology and the rapid development of Internet of things technology have become one of the important symbols of modern city. This paper mainly studies the circuit system based on cloud edge fusion outdoor intelligent light networking. Based on the development of wireless networking technology of new light source and sensor and data communication and processing technology of Internet of things, this paper analyzes the development trend and support status of intelligent lighting system, summarizes the overall demand for intelligent lighting system, and proposes a complete set of communication interface software, data‐processing software, operation management software, and street lamp controller group system architecture. The street lamp controller realizes the short distance wireless network through ZigBee technology and realizes the communication interaction of control and state acquisition data by GPRS wireless transmission technology. This paper tests the real‐time performance, packet loss rate, and stability of sensor data service provided by sensor nodes in the system. Finally, the monitoring experiments of the lighting circuit system are carried out, and the status of all street lamps in the centralized controller of street lamps is inquired every 5 min for 20 times. In these 20 times, the success rate of the first return of the switch state of the lamp is 100%, while that of the current and voltage is 98.6%. The experimental results show that the design of the lighting circuit system is feasible and the system runs stable and realizes the intelligent monitoring of the lighting system. [ABSTRACT FROM AUTHOR]

A method for the synthesis of enantiopure eight-membered nitrogen heterocycles has been developed through diastereoselective cross-coupling of 2-iodobiphenyls with 2-bromobenzylamines. The products represent a novel type of chiral scaffold, which feature easy modification and high configurative stability and have the potential to be applied in asymmetric synthesis. Palladacycles that were formed via the C–H activation of 2-iodobiphenyls should act as the intermediates. The reaction provides a new strategy for the synthesis of medium-sized ring compounds. [ABSTRACT FROM AUTHOR]

The paper mainly focuses on the synchronization of multiple-weight Markovian switching complex networks under nonlinear coupling mode. Based on the finite-time stability theory, Itô's lemma, and some inequality technologies, the synchronization criterion of network models in the nonlinear coupling mode is obtained; at the same time, unknown parameters of networks are also identified by an effective controller. In addition, several corollaries are given to illustrate the general applicability of the control rules in the paper. Finally, two typical numerical simulations are given to prove the rationality and feasibility of theoretical analysis of network models. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed cross-coupling reaction of aryl halides with 2-chlorobenzoic acids has been developed. The reaction forms C(sp3), C(sp2)-palladacycles through C(sp3)–H activation. The palladacycles react with 2-chlorobenzoic acids through two successive C–C cross-couplings, and two C–C bonds are formed with high chemoselectivity. The reaction provides an innovative method for the synthesis of 9,10-dihydrophenanthrenes. [ABSTRACT FROM AUTHOR]

A Pd(II)-catalyzed intermolecular C–H silylation reaction initiated by aminopalladation has been developed. The C–H bonds were activated by an alkyl Pd(II) species generated through aminopalladation and then disilylated with hexamethyldisilane to form disilylated indolines as the final products. The reaction provides a new method for the introduction of silyl groups into complex organic molecules. [ABSTRACT FROM AUTHOR]

Two methods for the synthesis of norbornane‐fused indanes via palladium‐catalyzed three‐component reactions of iodoarenes, norbornenes, and CH2Br2 or α‐diazoesters have been developed. In the reactions, three C−C bonds were constructed and a wide range of norbornane‐fused indanes could be synthesized. The reactions with α‐diazoesters proceeded with a high degree of diastereoselectivity and indanes bearing an all‐carbon quaternary center were formed. The products obtained in the reactions of 1,4‐dihydro‐1,4‐epoxynaphthalene can be converted to fluorenes, providing an alternative way to access fluorene derivatives. [ABSTRACT FROM AUTHOR]

Abstract Primary autosomal recessive microcephaly (MCPH) is a rare hereditary disease characterized by congenitally small with brain circumference of the head below 3 standard deviations (SD). By far, 18 MCPH genes have been reported to be associated with the disease. SASS6 gene functioned in assembly of centrioles that the majority of MCPH genes present at the centrosome. There was only research reporting a homozygous missense mutation in SASS6 gene detected in a consanguineous Pakistani family. By conducting Whole-exome sequencing (WES) and Sanger sequencing on the family trio, we identified two novel splice site mutations c.127-13A>G and c.1867+2T>A in compound heterozygous hereditary form in the SASS6 gene. The two mutations were confirmed to alter mRNA splicing by RT-PCR assay. Our finding supported the role of SASS6 in the pathogenesis of microcephaly, expanding mutation spectrums and contributing to understanding of molecular mechanisms of MCPH. Highlights • We report SASS6 compound heterozygous mutations in a Chinese family with MCPH. • Our analysis is the second mutation report of SASS6 gene of the world. • c.127-13A>G and c.1867+2T>A are novel splice site mutations of SASS6. [ABSTRACT FROM AUTHOR]

Pd-catalyzed C–H silylation reactions remain underdeveloped. General strategies usually rely on the use of complex bidentate directing groups. C,C- Palladacycles exhibit extremely high reactivity towards hexamethyldisilane and can be disilylated very efficiently. The C,C- palladacycles are prepared through halide-directed C–H activation. This account introduces Pd-catalyzed C–H silylation reactions with di-silanes as the silyl source, and is focused on studies on the silylation of C,C- palladacycles. 1 Introduction and Background 2 Allylic C–H Silylation Reaction 3 Coordinating-Ligand-Directed C–H Silylation Reaction 4 Disilylation of C (sp2), C (sp2) - Palladacycles That are Generated by C(sp2)–H activation 5 Disilylation of C (sp2), C (sp3) - Palladacycles That are Generated by C(sp3)–H Activation 6 Disilylation of C , C- Palladacycles That are Generated through Domino Processes 7 Summary and Outlook [ABSTRACT FROM AUTHOR]

An efficient approach for the synthesis of benzimidazoles has been developed through the Pd‐catalyzed amination of 2‐iodobenzimines with diaziridinone. A wide range of 2‐(hetero)aryl benzimidazloes are synthesized in good to excellent yields. The reactions likely involve C,C‐palladacycles derived from 2‐iodobenzimines as the key intermediate, and the palladacycles reacted with diaziridinone to form benzimidazoles. [ABSTRACT FROM AUTHOR]

An approach for the synthesis of benzofulvenes has been developed through palladium‐catalyzed sequential three‐component reactions. The reactions likely involve C,C‐palladacycles as the key intermediates. The palladacycles are generated through cascade reactions of aryl halides and alkynes, and then reacted with CH2Br2 to form benzofulvenes as the final products. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed sequential three-component reaction has been developed. The palladacycles, generated through cascade reactions of aryl halides and alkynes, are the key intermediates and react with hexamethyldisilane to form disilylated products. The reaction represents a useful preparative method for vinylsilanes, and the vinylsilanes can be transformed into tetrasubstituted alkenes. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of various C,C‐palladacycles that were generated through the C−H activation of aryl halides with disilanes have been studied. The reaction of arylnorbornyl palladacycles, which were generated through a Catellani reaction, with hexamethyldisilane proceeded very efficiently to afford disilylated products. Palladacycles that were obtained through the remote C−H activation of aryl halides that contained a styrene moiety with an ether linkage also underwent a disilylation reaction with hexamethyldisilane. Furthermore, the reactions of dibenzopalladacyclopentadienes, which were generated from 2‐iodobiphenyls, with diphenyltetramethyldisilane were also investigated and a range of 2‐iodobiphenyls were disilylated in moderate yields. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient palladium‐catalyzed disilylation reaction of aryl halides through C−H activation has been developed for the first time. The reaction has broad substrate scope. A variety of aryl halides can be disilylated by three types of C−H activation, including C(sp2)−H, C(sp3)−H, and remote C−H activation. In particular, the reactions are also unusually efficient. The yields are essentially quantitative in many cases, even in the presence of less than 1 mol % catalyst and 1 equivalent of the silylating reagent under relatively mild conditions. The disilylated biphenyls can be converted into disiloxane‐bridged biphenyls. [ABSTRACT FROM AUTHOR]

Abstract: A facile and efficient approach has been developed for the synthesis of carbazoles from 2‐iodobiphenyls and diaziridinone under palladium catalysis. A wide range of carbazoles were synthesized in good to excellent yields, and indole derivatives were obtained by using styrenes as the substrate. The palladacycles obtained from 2‐iodobiphenyls acted as the key intermediate, and the reaction should proceed via a tandem Pd‐catalyzed C−H activation/dual C−N bond formation sequence. [ABSTRACT FROM AUTHOR]

Utilizing halogens as traceless directing goups represents an attractive strategy for C−H functionalization. A two C−H alkylation system, initiated by the oxidative addition of organohalides to Pd0, has been developed. The first reaction involves an intermolecular alkylation of palladacycles to form C(sp3)−C(sp2) bonds followed by C(sp2)−H activation/cyclization to deliver alkylated benzocyclobutenes as the final products. In the second reaction, two C−C bonds are formed by the reaction of palladacycles with CH2Br2, and provides a facile and efficient method for the synthesis of indanes. The alkylated benzocyclobutene products can be transformed into tricyclic hyrocarbons, and the indane derivatives are essential structural motifs in bioactive and odorant molecules. [ABSTRACT FROM AUTHOR]

A facile and efficient approach for the synthesis of spirooxindoles has been developed via the coupling of spirocyclic C,C-palladacycles with CH2Br2. The key spirocyclic palladacycles are generated catalytically via remote C–H activation. A range of spirooxindoles can be synthesized in good to excellent yields from readily available starting material. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalysed ortho-C-H olefination of α,α-difluorophenylacetic acid derivatives using 8-aminoquinoline as a bidentate directing group has been developed. A range of olefinated arenes can thus be synthesized in a concise way. This reaction provides an easy and straightforward route to a panel of difluoromethylated arene analogues in moderate to good yields, with a satisfactory tolerance of common functional groups. Transformation of the products into a variety of other difluoromethylene-containing compounds demonstrates the utility of this method. [ABSTRACT FROM AUTHOR]

Glutaric aciduria type I (GA-I) is a rare autosomal recessive metabolic disorder caused by deficiency of glutaryl-CoA dehydrogenase (GCDH), leading to an abnormal metabolism of lysine, hydroxylysine and tryptophan. It results in accumulations of glutaric acid, 3-hydroxyglutaric acid and glutaconic acid. Clinical features include the sudden onset of encephalopathy, hypotonia and macrocephaly usually before age 18 months. Here we report five cases of GA-I confirmed with mutation analysis. GCDH gene mutations were identified in all five probands with GA-I. Three of them had compound heterozygous mutations and two had homozygous mutations. Mutations of two alleles (c.334G > T and IVS11-11A > G) were novel and both of them were confirmed to be splice site mutations by reverse transcription PCR. [ABSTRACT FROM AUTHOR]