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The recent surge in the applications of deuterated drug candidates has rendered an urgent need for diverse deuterium labeling techniques. Herein, an efficient Rh-catalyzed deuterated Tsuji-Wilkinson decarbonylation of naturally available aldehydes with D

Due to the low manufacture cost and easy installation, tubal structures are common utilized as energy absorbers in automotive and other engineering industries. In the present work, four novel reinf...

A rhodium-catalyzed asymmetric allylic alkylation of pyrazol-5-ones with internal alkynes is illustrated. In the presence of a chiral rhodium-hydride catalyst, functionalized heterocyclic products bearing an all-carbon quaternary stereogenic center were obtained in high yields with satisfactory enantioselectivities. This protocol also features good regiocontrol and a high atom economy without stoichiometric by-product formation.

Butafulvene is a constitutional isomer of benzene, comprising a cyclobutene skeleton bearing two exocyclic conjugated methylene units. As a result of the intrinsic high strain energy and anti-aromaticity, the preparation of butafulvene compounds has been a fundamental issue for the development of butafulvene chemistry. Here an efficient palladium-catalysed coupling protocol involving propargylic compounds has been developed, providing a solid and versatile strategy for the rapid assembly of symmetric butafulvene derivatives. Based on mechanistic studies, two complementary mechanisms, both involving palladium catalysis, have been confirmed. With the mechanism unveiled, the synthesis of non-symmetric butafulvenes has also been achieved. Advantages of this strategy include tolerance to a wide range of propargylic molecules, mild reaction conditions, simple catalytic systems and easy scalability. The synthetic potential of the products as platform molecules for cyclobutene derivatives has also been demonstrated.

[Objective] To study the effect of postoperative fixation parameters on the biomechanical performance of femur under two kinds of fractures modes. [Method] Several human femurs samples with fracture were prepared and fixed adopting different parameters for the compression test via universal testing machine, the stress of femur and intramedullary nail under the trochanter was extracted. The geometric model of femoral fracture was created by three-dimensional reconstruction using Mimics software, and the finite element models of femur under two fracture modes were established in Hypermesh. The numerical analysis of femur under the vertical load was carried out using Abaqus, and the model was verified by compression experimental results. Based on the verified numerical model, the influence of the positions of lag screw, the angles between lag screws and intramedullary nail, and the implantation position of intramedullary nail were investigated through the combination of different factors. [Results] For the trochanteric fracture mode, the angle of 125° between the neck nail and the intramedullary nail, of the intramedullary nail was implanted at the intertrochanteric fossa, and the head-neck tension screw was located in the bottom position is beneficial to obtain better postoperative fixation performance. However, for the reserve fracture mode, the angle of 125° between the head-neck tension screw and the intramedullary nail, the intramedullary nail was implanted from the intertrochanteric tip, and the head-neck tension screw was fixed the top position, which is beneficial to obtain better postoperative fixation bio-mechanical performance. [Conclusion] The bio-mechanical performance of postoperative femur is affected by the comprehensive action of angle between the intramedullary nail and the head-neck tension screw, the position of the intramedullary nail, position of the head-neck tension screws, the biomechanical performance of the femur is also different with various fixation manner. The results and conclusions of this work may be of significant reference to the further investigation of treatment for femoral fracture.

An efficient method for the synthesis of alkyl indium reagents by means of an indium(III) or lead(II) halidecatalyzed direct insertion of indium into alkyl iodides and their applications in palladium-catalyzed crosscoupling reactions with aryl halides is developed. NMR and ESI-MS analyses indicated that rather than the formation of the commonly recognized alkyl indium sesquihalide with the formulation of R3In2X3, the formed alkyl indium reagent in the present protocol should be a mixture of an alkyl indium dihalide (RInX2) and a dialkyl indium halide (R2InX) (both of them presumably exist as dimers). Nanyang Technological University We gratefully acknowledge the financial support from the Nanjing Tech University (Start-up Grant No. 39837118, 39837101, and 39837146), the SICAM Fellowship from the Jiangsu National Synergetic Innovation Center for Advanced Materials, and the Nanyang Technological University.

Through the oxidative addition of cobalt into the N-C(O) bond of phthalimide and the subsequent decarbonylation, we describe an efficient cobalt-catalyzed intermolecular decarbonylative carboamidation of alkynes. High regioselectivities have been achieved for unsymmetrical alkynes (including aryl-alkyl or aryl-aryl) to deliver polysubstituted isoquinolones. To facilitate step economy, a three-component decarbonylative carboamidation of alkynes with phthalic anhydrides and amines has been demonstrated using the current cobalt catalysis.

An efficient method for the preparation of alkyl indium reagents by using unactivated and cheap alkyl chlorides as substrates in the presence of indium and LiI was developed. The thus-formed alkyl indium species effectively underwent palladium-catalyzed cross-coupling reactions with aryl halides with wide functional group tolerance.

Carbon dioxide is commonly used as one of the significant environmental factors to control pileus expansion during mushroom cultivation. However, the pileus expansion mechanism related to CO2 is still unknown. In this study, the young fruiting bodies of a popular commercial mushroom Flammulina filiformis were cultivated under different CO2 concentrations. In comparison to the low CO2 concentration (0.05%), the pileus expansion rates were significantly lower under a high CO2 concentration (5%). Transcriptome data showed that the up-regulated genes enriched in high CO2 concentration treatments mainly associated with metabolism processes indicated that the cell metabolism processes were active under high CO2 conditions. However, the gene ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with cell division processes contained down-regulated genes at both 12 h and 36 h under a high concentration of CO2. Transcriptome and qRT-PCR analyses demonstrated that a high CO2 concentration had an adverse effect on gene expression of the ubiquitin–proteasome system and cell cycle–yeast pathway, which may decrease the cell division ability and exhibit an inhibitory effect on early pileus expansion. Our research reveals the molecular mechanism of inhibition effects on early pileus expansion by elevated CO2, which could provide a theoretical basis for a CO2 management strategy in mushroom cultivation.

An efficient method for the synthesis of alkyl indium reagent by means of an iodine-catalyzed direct indium insertion into alkyl iodide in THF is reported. The thus-generated alkyl indium reagents effectively underwent Pd-catalyzed cross-coupling reactions with various aryl halides, exhibiting good compatibility to a variety of sensitive functional groups. By replacing THF with DMA and using 0.75 equiv of iodine, less reactive alkyl bromide could be used as substrate for indium insertion with equal ease. Nanyang Technological University We gratefully acknowledge the financial support from Nanjing Tech University (Start-up Grant No. 39837118, 39837101, and 39837146), the SICAM Fellowship from Jiangsu National Synergetic Innovation Center for Advanced Materials, and Nanyang Technological University.

An efficient water-based method for the synthesis of alkylindium compound in the presence of a catalytic amount of cheap and readily available CuSO4·5H2O (10 mol%) was developed. The thus-generated alkylindium compounds effectively underwent palladium-catalyzed cross-coupling reactions with a myriad of aryl halides in aqueous media, leading to the cross-coupled products in modest to high yields. The mildness of the formed alkyl organometallics allowed the tolerance to various important functional groups incorporated in both substrates of alkyl iodides and aryl halides.

The direct insertion of indium powder into alkyl iodides was found to be efficiently catalyzed by a catalytic amount of cobalt(II) bromide (10 mol%). Upon subjection of the thus-formed alkylindium compounds to palladium-catalyzed cross-coupling reactions with a wide range of aryl halides, a series of cross-coupled products could be obtained in moderate to good yields with the tolerance to many important functional groups.

The range of movement(ROM) of adjacent segments and the change of intervertebral disc stress after implanting artificial cervical disc are investigated. The contact problem for bio-modeling is introduced. A normal cervical spine finite element model is proposed. The bone graft and fusion between C5 and C6 and C5/6 artificial disc implantation were simulated. The range of movement on adjacent segment and the change of intervertebral disc’s stress in such two cases are analyzed. Computational results show that the model includes the ligaments, joint capsule and other soft tissue structures, which is real, fine and high accuracy. When the adjacent intervertebral ROM was increased after interbody fusion surgery, the stress of corresponding intervertebral disc was increased obviously and the stress of upper segment of nucleus pulposus and annulus fibrosus were also increased about 70% ,besides the next-bit segments was increased about 40%. There were no differences among cervical spine ROM except extension (p> 0.05) after the implantation of artificial disc, and the stress on adjacent segments was increased less than 10%. The implantation of artificial cervical disc can release the stress on adjacent segments in a certain extent, and resume cervical activities at the same time.

Appling the contact theory The finite element model of L1-L5 segment was established with self-compiled software and Hyper Mesh. Based on the spine CT continuous images of L1-L5 segments of the healthy volunteer, the three-dimensional finite elements model of L1-L5 vertebrae structure was constructed by the combination of self-compiled software and Hyper Mesh. endplates and joint cartilage intervertebral disc and ligament structure were also simulated. Between the high and low articular processes adopts the surface - surface contact theory to carry on processing. The three-dimensional finite element model was built structure integrity,with good geometric similarity. The results of the finite element model were matched to the results of the vitro experiment of biomechanics. The use of self-compiled software and Hyper Mesh can improve the finite element model of lumbar motion segment building speed and accuracy, the introduction of contact theory finite element model can improve the reliability and auteenticity.

Higher speed and loading capacity of trains nowadays have aroused higher ability of crashworthiness, which could be effectively improved by well-designed energy absorbing structures. The thin-walled components, the most traditional and effective energy absorbing device, have been widely used for design of energy absorbing device. As a result, the thin-walled components are used as an example to examine the process of axial compression of it. A comparison of a dynamic compressing simulation on fold-collapse tube and the experimental result of it is made, which shows the two matches very well. Based on this comparison, a further research and optimization on the thin-walled energy absorbing components is implemented. With the material modal and finite element modal of this component, a research on the simulation of PAM-CRASH, the crashing finite element Software, is implemented on such component with different shapes of cross-section, different thickness and square cross-sections with single-cell and multi-cell. What's more, suggestions on such thin-walled components energy absorbing structure is given based on the analysis of the parameters of the simulation.