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Homogeneous distribution of graphene flakes in a polymer matrix, still preserving intrinsic material properties, is key to successful composite applications. A novel approach is presented to disperse non-oxidized graphene flakes with non-covalent functionalization of 1-pyrenebutyric acid and to fabricate nanocomposites with outstanding thermal conductivity (∼1.53 W/mK) and mechanical properties (∼1.03 GPa).

The photoluminescence (PL) origin of bright blue emission arising from intrinsic states in graphene quantum dots (GQDs) is investigated. The bright PL of intercalatively acquired GQDs is attributed to favorably formed subdomains composed of four to seven carbon hexagons. Random and harsh oxidation which hinders the energetically favorable formation of subdomains causes weak and redshifted PL.

Graphical abstract AuthorsSorafenib vs. sorafenib + cTACE in patients with advanced HCC vs. HighlightsSorafenib combined with concurrent chemoembolization did not improve overall survival.Combination therapy significantly improved tumor response and secondary outcomes.Sorafenib alone remains first-line standard of care for advanced hepatocellular carcinoma. Lay summaryFor patients with advanced hepatocellular carcinoma requiring sorafenib therapy, co-administration with conventional transarterial chemoembolization did not improve overall survival compared to sorafenib alone. Therefore, sorafenib alone remains the first-line standard of care for patients with advanced hepatocellular carcinoma.http://dx.improved time to progression, progression-free survival, and tumor response rate. Sorafenib alone remains the first-line standard of care for patients with advanced HCC.Lay summary: For patients with advanced hepatocellular carcinoma requiring sorafenib therapy, co-administration with conventional transarterial chemoembolization did not improve overall survival compared to sorafenib alone. Therefore, sorafenib alone remains the first-line standard of care for patients with advanced hepatocellular carcinoma. Clinical Trial Number: NCT01829035. Ó 2018 European Association for the Study of the Liver. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Liver cancer is the sixth most common cancer (fourth in men and sixth in women) and the second largest cause of cancer mortality in South Korea. The crude incidence rate of liver cancer was 31.9/100,000 (47.5/100,000 in men and 16.2/100,000 in women) and the age-standardized incidence rate was 19.9/100,000 (32.4/100,000 in men and 8.8/100,000 in women) in 2014. The crude incidence rate increased from 1999 to 2011 and thereafter showed a subtle decreasing tendency. The crude prevalence rate was 113.6/100,000 (170.2/100,000 in men and 57.1/100,000 in women) and the age-standardized prevalence rate was 72.6/100,000 (115.7/100,000 in men and 33.7/100,000 in women) in 2014, which increased from 2010 to 2014. Survival from liver cancer has improved over the last two decades. The 5-year relative survival rate was markedly increased from 10.7% in those diagnosed with liver cancer between 1993 and 1995 to 32.8% in those diagnosed between 2010 and 2014. The epidemiology of liver cancer is influenced by that of underlying liver diseases such as viral hepatitis. Substantial progress has been made in the prevention and treatment of viral hepatitis; however, uncontrolled alcoholic liver disease, obesity and diabetes appears to have the potential to emerge as major causes for liver cancer. Depending on the success of the control of risk factors, the epidemiology of liver cancer in Korea may change.

Misfolding and aggregation of amyloid beta (Aβ)-40 peptide play key roles in the development of Alzheimer's disease (AD). However, very little is known about the molecular mechanisms underlying these molecular processes. We developed a novel experimental approach that can directly probe aggregation-prone states of proteins and their interactions. In this approach, the proteins are anchored to the surface of the AFM substrate (mica) and the probe, and the interaction between anchored molecules is measured in the approach-retraction cycles. We used dynamic force spectroscopy (DFS) to measure the stability of transiently formed dimers. One of the major findings from DFS analysis of α-synuclein (α-Syn) is that dimeric complexes formed by misfolded α-Syn protein are very stable and dissociate over a range of seconds. This differs markedly from the dynamics of monomers, which occurs on a microsecond-nanosecond time scale. Here we applied the same approach to quantitatively characterize interactions of Aβ-40 peptides in a broad range of pH values. These studies showed that misfolded dimers are characterized by the lifetimes in the range of seconds. This value depends on pH and varies between 2.7 s for pH 2.7 and 0.1 s for pH 7, indicating that the aggregation properties of Aβ-40 are modulated by the environmental conditions. The analysis of the contour lengths revealed the existence of various pathways for dimer dissociation, suggesting that dimers with different conformations are formed. These structural variations result in different aggregation pathways, leading to different types of oligomers and higher order aggregates, including fibrils.

The increasing demand for graphene has required a new route for its mass production without causing extreme damages. Here we demonstrate a simple and cost-effective intercalation based exfoliation method for preparing high quality graphene flakes, which form a stable dispersion in organic solvents without any functionalization and surfactant. Successful intercalation of alkali metal between graphite interlayers through liquid-state diffusion from ternary KCl-NaCl-ZnCl(2) eutectic system is confirmed by X-ray diffraction and X-ray photoelectric spectroscopy. Chemical composition and morphology analyses prove that the graphene flakes preserve their intrinsic properties without any degradation. The graphene flakes remain dispersed in a mixture of pyridine and salts for more than 6 months. We apply these results to produce transparent conducting (∼930 Ω/□ at ∼75% transmission) graphene films using the modified Langmuir-Blodgett method. The overall results suggest that our method can be a scalable (>1 g/batch) and economical route for the synthesis of nonoxidized graphene flakes.

wileyonlinelibrary.comCOMMUNICATION electrochemical processing, [ 9 ] have been suggested to date. Despite some success in the synthesis of GQDs, these methods have limitations as well, such as the requirement of special equipment and extremely expensive raw materials, long fabrication times, low production yields, and the use of harmful chemical reagents. In this contxt, the method of oxidation and a further cutting reaction of graphite is appealing for the mass production of GQDs. [ 9,[11][12][13][17][18][19][20] However, numerous oxygenous functional groups and defects are inevitably generated both on the basal plain and at the edges of GQDs. This significantly infl uences the dispersion properties of GQDs and makes it diffi cult to control the emission wavelength of GQDs. [21][22][23][24] This oxidation of GQDs thwarts both fundamental understanding of the origin of luminescence and attempts to realize practical applications. In particular, the use of GQDs as an alternative to organic active materials for light-emitting diodes (LEDs) remains challenging due to low production yields and low quantum yields. The development of novel strategies to synthesize high-quality GQDs with controlled oxidation on a large scale is thus crucial.Herein, we suggest an easy and mass-producible route to obtain high-quality GQDs with controlled oxidation by graphite intercalation compounds (GICs). The proposed method is cost-effective and eco-friendly, as potassium-sodium tartrate (KNaC 4 H 4 O 6 ·4H 2 O) serves as both an intercalant into graphite and a solvent in the solvothermal reaction. After the formation of GICs, a dissolution process in water generates a large amount of GQDs (>60% yield) without requiring any surfactants or hazardous chemical solvents. More interestingly, in contrast to the visible emission of most GQDs synthesized from an oxidation method, our GQDs emit near the UV range (∼400 nm), which has been reported as the intrinsic emission wavelength of GQDs with low oxidation. [ 21,23,25 ] This result extends and confi rms our current understanding of the fl uorescence mechanisms of GQDs with respect to quantum confi nement effects, [26][27][28] recombination of localized electron-hole pairs, [ 8,18 ] triplet states from zigzag sites, [ 17 ] oxygenous emissive traps, [ 11 ] and intrinsic/extrinsic states. [ 25 ] We also found that the fl uorescence of GQDs originated from two overlapped spectral bands with intrinsic and extrinsic states and fi rst discovered the carrier transfer process from intrinsic to extrinsic states. Furthermore, the degree of oxygen content, which controls the fl uorescence color, was controlled simply by changing the sizes of the GQDs. These results were realized by preparing highquality GQDs with a narrowly distributed size via GICs.To confi rm the superior performance of these GQDs and suggest the possibility of optoelectronic applications, we With strong optical absorptivity and a widely tunable bandgap, graphene is an attractive material for optical and optoelectronic devices. [ 1,2 ...