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The controlled oxidation of alcohols to the corresponding ketones or aldehydes via selective cleavage of the β-C-H bond of alcohols under mild conditions still remains a significant challenge. Although the metal/oxide interface is highly active and selective, the interfacial sites fall far behind the demand, due to the large and thick support. Herein, we successfully develop a unique Au-CuO Janus structure (average particle size=3.8 nm) with an ultrathin CuO layer (0.5 nm thickness) via a bimetal in situ activation and separation strategy. The resulting Au-CuO interfacial sites prominently enhance isopropanol adsorption and decrease the energy barrier of β-C-H bond scission from 1.44 to 0.01 eV due to the strong affinity between the O atom of CuO and the H atom of isopropanol, compared with Au sites alone, thereby achieving ultrahigh acetone selectivity (99.3 %) over 1.1 wt % AuCu

Chromosome painting is a powerful technique for chromosome and genome studies. We developed a flexible chromosome painting technique based on multiplex PCR of a synthetic oligonucleotide (oligo) library in cucumber (Cucumis sativus L., 2n = 14). Each oligo in the library was associated with a universal as well as nested specific primers for amplification, which allow the generation of different probes from the same oligo library. We were also able to generate double-stranded labelled oligos, which produced much stronger signals than single-stranded labelled oligos, by amplification using fluorophore-conjugated primer pairs. Oligos covering cucumber chromosome 1 (Chr1) and chromosome 4 (Chr4) consisting of eight segments were synthesized in one library. Different oligo probes generated from the library painted the corresponding chromosomes/segments unambiguously, especially on pachytene chromosomes. This technique was then applied to study the homoeologous relationships among cucumber, C. hystrix and C. melo chromosomes based on cross-species chromosome painting using Chr4 probes. We demonstrated that the probe was feasible to detect interspecies chromosome homoeologous relationships and chromosomal rearrangement events. Based on its advantages and great convenience, we anticipate that this flexible oligo-painting technique has great potential for the studies of the structure, organization, and evolution of chromosomes in any species with a sequenced genome.

BACKGROUND Intronic (TTTCA)n insertions in the SAMD12, TNRC6A, and RAPGEF2 genes have been identified as causes of familial cortical myoclonic tremor with epilepsy. OBJECTIVE To identify the cause of familial cortical myoclonic tremor with epilepsy pedigrees without (TTTCA)n insertions in SAMD12, TNRC6A, and RAPGEF2. METHODS Repeat-primed polymerase chain reaction, long-range polymerase chain reaction, and Sanger sequencing were performed to identify the existence of a novel (TTTGA)n insertion. Targeted long-read sequencing was performed to confirm the accurate structure of the (TTTGA)n insertion. RESULTS We identified a novel expanded intronic (TTTGA)n insertion at the same site as the previously reported (TTTCA)n insertion in SAMD12. This insertion cosegregated with familial cortical myoclonic tremor with epilepsy in 1 Chinese pedigree with no (TTTCA)n insertion. In the targeted long-read sequencing of 2 patients and 1 asymptomatic carrier in this pedigree, with 1 previously reported (TTTCA)n -insertion-carrying patient as a positive control, a respective total of 302, 159, 207, and 50 on-target subreads (predicated accuracy: ≥90%) spanning the target repeat expansion region were generated. These sequencing data revealed the accurate repeat expansion structures as (TTTTA)114-123 (TTTGA)108-116 in the pedigree and (TTTTA)38 (TTTCA)479 in (TTTCA)n -insertion-carrying patient. CONCLUSION The targeted long-read sequencing helped us to elucidate the accurate structures of the (TTTGA)n and (TTTCA)n insertions. Our finding offers a novel possible cause for familial cortical myoclonic tremor with epilepsy and might shed light on the identification of genetic causes of this disease in pedigrees with no detected (TTTCA)n insertion in the reported causative genes. © 2019 International Parkinson and Movement Disorder Society.

It is an emerging focus to explore controlled release drug delivery systems for simultaneous cancer imaging and therapy. Herein, we synthesized a photothermal sensitive multifunctional nano-liposome drug delivery system, with doxorubicin wrapped in the hydropholic layer as the therapeutical agent and cypate doped in the hydrophobic layer as the diagnostic agent. A series of in vitro and in vivo characterization demonstrated the stability of synthesized liposome, as the DL% was 9 ± 1.5 and the EE% was 82.7 ± 2.1. And the liposome achieved the functions of target-delivery, enhanced photochemical internalized drug release, and simultaneous chemotherapy and thermal therapy, indicating that this multifunctional nano-liposome is a promising drug delivery system for tumor diagnosis and targeting therapy.

We recently reported the development of a computational method for the design of coassembling multicomponent protein nanomaterials. While four such materials were validated at high-resolution by X-ray crystallography, low yield of soluble protein prevented X-ray structure determination of a fifth designed material, T33-09. Here we report the design and crystal structure of T33-31, a variant of T33-09 with improved soluble yield resulting from redesign efforts focused on mutating solvent-exposed side chains to charged amino acids. The structure is found to match the computational design model with atomic-level accuracy, providing further validation of the design approach and demonstrating a simple and potentially general means of improving the yield of designed protein nanomaterials.

We put forward a novel single selection transmission scheme based on maximum desired signal criterion and investigate the capacity of distributed antenna systems in multicell environment. However, for most of the recent literatures, the interference plus noise is treated as Gaussian random variable with fixed variance by the central limit theorem, which ignores the effect of the short-term fading on interference. To avoid it, non-central limit theorem is adopted in which the variance of interference plus noise is considered as a random variable with changeable variance influenced by the short-term fading. Moreover, channels are assumed to suffer from independent identical Rayleigh fading together with propagation path loss, and the closed-form expression of capacity for distributed antenna systems is derived. Finally, extensive simulations are carried out to validate the theoretical analysis. Copyright © 2015 John Wiley & Sons, Ltd.

An OH terminated hyperbranched polyester is used to stabilize TiO2 nanomaterials (10 nm) in situ synthesized via a sol–gel method with butyltitanate as precursor. X-ray diffraction (XRD) analyses and thermogravimetric (TGA) analyses illustrate the interactions of the hyperbranched polyester with the TiO2 nanoparticles. The stabilized TiO2 nanocomposites are used in the finishing process of Vectran and a continuous uniform TiO2 coating on the Vectran fiber surface is achieved. The TiO2-treated Vectran filaments exhibit an increased tensile strength compared to the untreated Vectran systems upon exposure to Xenon lamp UV radiation. The coating leads to improved UV-blocking performance.

In this paper, based on maximum signal-to-interference-plus-noise ratio criterion at the receiver, we propose a single transmission selection scheme for distributed antenna system and investigate the corresponding ergodic capacity together with outage probability in multicell environment. Assuming that the channels suffer from independent non-identical Nakagami-m fading with integer values of fading severity parameter m, we derive exact closed-form expressions for the ergodic capacity and outage probability. Monte-Carlo simulations are carried out to validate the theoretical analysis. Simulation results show that the ergodic capacity and outage probability of the proposed single transmission selection scheme outperform that of blanket transmission scheme. Copyright © 2013 John Wiley & Sons, Ltd.

Bacterial microcompartments (MCPs) are large proteinaceous structures comprised of a roughly icosahedral shell and a series of encapsulated enzymes. MCPs carrying out three different metabolic functions have been characterized in some detail, while gene expression and bioinformatics studies have implicated other types, including one believed to perform glycyl radical-based metabolism of 1,2-propanediol (Grp). Here we report the crystal structure of a protein (GrpN), which is presumed to be part of the shell of a Grp-type MCP in Rhodospirillum rubrum F11. GrpN is homologous to a family of proteins (EutN/PduN/CcmL/CsoS4) whose members have been implicated in forming the vertices of MCP shells. Consistent with that notion, the crystal structure of GrpN revealed a pentameric assembly. That observation revived an outstanding question about the oligomeric state of this protein family: pentameric forms (for CcmL and CsoS4A) and a hexameric form (for EutN) had both been observed in previous crystal structures. To clarify these confounding observations, we revisited the case of EutN. We developed a molecular biology-based method for accurately determining the number of subunits in homo-oligomeric proteins, and found unequivocally that EutN is a pentamer in solution. Based on these convergent findings, we propose the name bacterial microcompartment vertex for this special family of MCP shell proteins.

It is highly challenging but desirable to develop efficient heterogeneous catalysts for C-Cl bond activation in coupling reactions. Here, we succeeded in synthesizing bimetallic Pd-Au nanoparticles through a convenient one-pot wet chemical route. The composition and alloyed structure of the as-prepared nanoparticles were fully characterized. We have evaluated the catalytic activity of these Pd-Au alloy catalysts in Buchwald-Hartwig reactions of aryl chlorides. The excellent catalytic activity of the as-obtained Pd-Au nanoparticles indicates that exploiting the catalytic power of nano-alloy catalysts could enable effective C-Cl bond activation suitable for cross-coupling reactions.

This study comparatively evaluates the characteristics of glutaraldehyde-treated acellular bovine and donkey pericardium using histological and electronic microscopic observation techniques, shrinkage temperature, and mechanical properties, as well as determining calcium and phosphorus content at 4 and 8 weeks after the subcutaneous implantation of donkey and bovine pericardium in Wistar rats. Donkey pericardium was significantly thinner compared with bovine pericardium (1.622 ± 0.161 mm vs. 4.027 ± 0.401 mm, P

SUMMARY This paper advocates the capacity analysis of an amplify-and-forward cooperative communication system model in multi-relay multiuser networks. A two-step selection scheme is adopted, and both relay and user selection are based on the outdated channel state information. Exact expression of channel capacity for independent, but not necessarily identically distributed, Rayleigh fading channels is derived. Finally, simulations are carried out to verify the correctness of theoretical analysis and illustrate the effect of parameters on the performance. Results show that although the performance of our scheme is inferior to the optimal joint selection scheme, it is still a practical scheme because its complexity is much lower than that of the optimal scheme. Copyright © 2012 John Wiley & Sons, Ltd.

Shape memory epoxy resins are derived on reacting E51 with triethylenetetramine in presence of the toughening agent polypropylene glycol diglycidyl ether (PPGDGE). The curing behaviors are studied with differential scanning calorimetry. The toughening system shows a decrease in activation energy. Sestak–Berggren model is utilized to establish the kinetic equations. The fitting results prove that the equations can well describe the reactions. Tensile tests and dynamic mechanical analysis are used to analyze mechanical performances and thermodynamics. Shape memory properties are characterized by fold-deploy tests. The elongation at break increases as the concentration of PPGDGE increases. The toughening materials have lower glass transition temperature (Tg). The fixable ratios of all systems are greater than 99.5%. The shape recovery time decreases with increasing the PPGDGE concentration. The optimal system can fully recover its original shape in about 2 min at Tg + 30°C, and exhibit the maximum fold-deploy cycles as 13 cycles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40853.

The resistance of cancer cells to photothermal therapy is closely related to the overexpression of heat shock proteins (HSPs), which are abnormally upregulated when cells are under lethal stresses. Common strategies that use small molecule inhibitors against HSPs to enhance hyperthermia effect lack spatial and temporal control of drug release, leading to unavoidable systemic toxicity. Herein, a versatile photothermal platform is developed which is composed of a hollow gold nanoshell core densely packed with small interfering RNAs against heat shock protein 70 (Hsp70). Upon near infrared light irradiation, the small interfering RNAs can detach from gold surface specifically and escape from endosomes for Hsp70 silencing. Meanwhile, the temperature increases for hyperthermia therapy due to the high photothermal efficiency of the nanoshells. Efficient downregulation of Hsp70 after light activation is achieved in vitro and in vivo. Ultimately, the light‐controlled dual functional nanosystem, with the effects of Hsp70 silencing and temperature elevation, results in sensitized photothermal therapy in nude mice model under mild temperature. This strategy smartly combines the localized photothermal therapy with controlled Hsp70 silencing, and has great potential for clinical translation with a simple and easily controlled structure.

Powders of the title compounds with x = 0, 0.05, 0.1, 0.2, and 0.3 are prepared by the sol—gel method starting with stoichiometric amounts of Ca(NO3)2, Pr(NO3)3, and Co(NO3)2 dissolved in aqueous citric acid solution (heating of the obtained gel at 1073 K for 8 h).