Al/C60 Nanocomposites Fabricated by High-Pressure Torsion

Al-2 vol pct fullerene (C60) composites with relative densities of >0.98 are manufactured by high-pressure torsion of ball-milled powders under an applied pressure of 6 GPa. A considerable Al grain refinement to similar to 53 nm and a homogeneous distribution of fullerenes give rise to a very high hardness of 152 Hv and yield stress of 405 MPa. Nevertheless, the poor tensile ductility due to the low work-hardening rate is achieved. (C) The Minerals, Metals & Materials Society and ASM International 2015open1144sciescopu

Electrical conductivity and electromagnetic interference shielding of multiwalled carbon nanotube composites containing Fe catalyst

Thin and flexible composite films of raw or purified multiwalled carbon nanotube (MWCNT) with various mass fractions and poly(methylmethacrylate) (PMMA) were synthesized for electromagnetic interference (EMI) shielding material. From scanning electron microscopy and high-resolution transmission electron microscopy photographs, we observed the formation of a conducting network through MWCNTs in an insulating PMMA matrix and the existence of an Fe catalyst in MWCNTs. The dc conductivity (sigma(dc)) of the systems increased with increasing MWCNT mass fraction, showing typical percolation behavior. The measured EMI shielding efficiency (SE) of MWCNT-PMMA composites by using the extended ASTM D4935-99 method (50 MHz-13.5 GHz) increased with increasing MWCNT mass fraction as sigma(dc). The highest EMI SE for raw MWCNT-PMMA composites was similar to27 dB, indicating commercial use for far-field EMI shielding. The contribution of absorption to total EMI SE of the systems is larger than that of reflection. Based on magnetic permeability, we suggest raw MWCNTs and their composites can be used for near-field EMI shielding.open28629

Proteins identification of wheat-rye translocation lines by MALDI-TOF-TOF mass spectrometry and ESI-QTOF/MS

OBJECTIVE: To examine the relationship between Timed Up and Go (TUG) performance, verbal executive function (EF) performance, and quality-of-life (QOL) measures in Parkinson's disease (PD). DESIGN: Cross-sectional. SETTING: Sixteen movement disorder centers from across the United States. PARTICIPANTS: Patients with PD (N=1964). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: TUG test, immediate and delayed 5-word recall, verbal fluency, PD QOL Questionnaire. RESULTS: TUG performance and verbal EF performance were significantly associated with, and predictors of, QOL measures, having the greatest association and predictability with the mobility domain of the QOL measures. CONCLUSIONS: The TUG test and verbal EF tests have QOL correlates, making the combined evaluation of mobility, cognitive, and QOL decline a potential examination tool to evaluate the sequelae of PD

Localized amyloidosis presenting with a penile mass: a case report

Amyloidosis is a disease characterized by the deposition of altered proteins in tissues. Amyloid deposition always occurs in the extracellular matrix and presents a fibrillary conformation. Local deposition of amyloid may occur in individual organs, without systemic involvement. We report here a rare case of localized penile shaft amyloidosis--an unusual location for amyloid deposition--presenting as a penile mass that resulted in a urethral stricture in 37-year old male patient. We have also comprehensively reviewed the literature regarding localized amyloidosis

Cardiac Transcription Factor Nkx2.5 Is Downregulated under Excessive O-GlcNAcylation Condition

Post-translational modification of proteins with O-linked N-acetylglucosamine (O-GlcNAc) is linked the development of diabetic cardiomyopathy. We investigated whether Nkx2.5 protein, a cardiac transcription factor, is regulated by O-GlcNAc. Recombinant Nkx2.5 (myc-Nkx2.5) proteins were reduced by treatment with the O-GlcNAcase inhibitors STZ and O-(2-acetamido-2-deoxy-D-glucopyroanosylidene)-amino-N-phenylcarbamate; PUGNAC) as well as the overexpression of recombinant O-GlcNAc transferase (OGT-flag). Co-immunoprecipitation analysis revealed that myc-Nkx2.5 and OGT-flag proteins interacted and myc-Nkx2.5 proteins were modified by O-GlcNAc. In addition, Nkx2.5 proteins were reduced in the heart tissue of streptozotocin (STZ)-induced diabetic mice and O-GlcNAc modification of Nkx2.5 protein increased in diabetic heart tissue compared with non-diabetic heart. Thus, excessive O-GlcNAcylation causes downregulation of Nkx2.5, which may be an underlying contributing factor for the development of diabetic cardiomyopathy

Protein Phosphatase 2A Controls Ethylene Biosynthesis by Differentially Regulating the Turnover of ACC Synthase Isoforms

The gaseous hormone ethylene is one of the master regulators of development and physiology throughout the plant life cycle. Ethylene biosynthesis is stringently regulated to permit maintenance of low levels during most phases of vegetative growth but to allow for rapid peaks of high production at developmental transitions and under stress conditions. In most tissues ethylene is a negative regulator of cell expansion, thus low basal levels of ethylene biosynthesis in dark-grown seedlings are critical for optimal cell expansion during early seedling development. The committed steps in ethylene biosynthesis are performed by the enzymes 1-aminocyclopropane 1-carboxylate synthase (ACS) and 1-aminocyclopropane 1-carboxylate oxidase (ACO). The abundance of different ACS enzymes is tightly regulated both by transcriptional control and by post-translational modifications and proteasome-mediated degradation. Here we show that specific ACS isozymes are targets for regulation by protein phosphatase 2A (PP2A) during Arabidopsis thaliana seedling growth and that reduced PP2A function causes increased ACS activity in the roots curl in 1-N-naphthylphthalamic acid 1 (rcn1) mutant. Genetic analysis reveals that ethylene overproduction in PP2A-deficient plants requires ACS2 and ACS6, genes that encode ACS proteins known to be stabilized by phosphorylation, and proteolytic turnover of the ACS6 protein is retarded when PP2A activity is reduced. We find that PP2A and ACS6 proteins associate in seedlings and that RCN1-containing PP2A complexes specifically dephosphorylate a C-terminal ACS6 phosphopeptide. These results suggest that PP2A-dependent destabilization requires RCN1-dependent dephosphorylation of the ACS6 C-terminus. Surprisingly, rcn1 plants exhibit decreased accumulation of the ACS5 protein, suggesting that a regulatory phosphorylation event leads to ACS5 destabilization. Our data provide new insight into the circuitry that ensures dynamic control of ethylene synthesis during plant development, showing that PP2A mediates a finely tuned regulation of overall ethylene production by differentially affecting the stability of specific classes of ACS enzymes

A Two-Step Hydrothermal Synthesis Approach to Monodispersed Colloidal Carbon Spheres

This work reports a newly developed two-step hydrothermal method for the synthesis of monodispersed colloidal carbon spheres (CCS) under mild conditions. Using this approach, monodispersed CCS with diameters ranging from 160 to 400 nm were synthesized with a standard deviation around 8%. The monomer concentration ranging from 0.1 to 0.4 M is in favor of generation of narrower size distribution of CCS. The particle characteristics (e.g., shape, size, and distribution) and chemical stability were then characterized by using various techniques, including scanning electron microscopy (SEM), FT-IR spectrum analysis, and thermalgravity analysis (TGA). The possible nucleation and growth mechanism of colloidal carbon spheres were also discussed. The findings would be useful for the synthesis of more monodispersed nanoparticles and for the functional assembly

Differential cross sections and spin density matrix elements for the reaction gamma p -> p omega

High-statistics differential cross sections and spin density matrix elements for the reaction gamma p -> p omega have been measured using the CLAS at Jefferson Lab for center-of-mass (CM) energies from threshold up to 2.84 GeV. Results are reported in 112 10-MeV wide CM energy bins, each subdivided into cos(theta_CM) bins of width 0.1. These are the most precise and extensive omega photoproduction measurements to date. A number of prominent structures are clearly present in the data. Many of these have not previously been observed due to limited statistics in earlier measurements