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Strong Goos-H\"anchen (GH) effect at a prism-graphene interface in the quantum Hall effect (QHE) condition is reported. Based on the full quantum description of the temperature-dependent surface conductivity of graphene present in the unconventional quantum Hall regime, magnetically strong tunable QHE GH shifts emerge. Our approach is based on deriving the generalized Fresnel coefficients with antisymmetric conductivity tensor for the Kerr phase of the incident linearly polarized light. Moreover, it is demonstrated that at low temperatures, GH shifts map plateaus as the intensity of the magnetic field grows. This quantum modulation of the GH effect in graphene by an applied magnetostatic bias may open doors to new opportunities for optical devices and QHE sensing applications in 2D materials., Comment: 6 figures

Ehsan Hashemi,1– 3 Omid Akhavan,4 Mehdi Shamsara,1,2 Saeid Ansari Majd,2 Mohammad Hossein Sanati,5 Morteza Daliri Joupari,1,2 Abbas Farmany6 1Animal Biotechnology Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 2National Research Center for Transgenic Mouse, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 3Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Physics, Sharif University of Technology, Tehran, Iran; 5Medical Genetics Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 6Dental Research Center, Hamadan University of Medical Sciences, Hamadan, IranCorrespondence: Morteza Daliri Joupari; Abbas Farmany Tel +98 21 4458-0340Fax +98 21 44580393Email daliri@nigeb.ac.ir; a.farmany@ut.ac.irBackground: Unique properties of graphene and its derivatives make them attractive in the field of nanomedicine. However, the mass application of graphene might lead to side effects, which has not been properly addressed in previous studies, especially with regard to its effect on the cell cycle.Methods: The effect of two concentrations (100 and 200 μg/mL) of nano- and microsized graphene oxide (nGO and mGO) on apoptosis, cell cycle, and ROS generation was studied. The effect of both sizes on viability and genotoxicity of the embryonic fibroblast cell cycle was evaluated. MTT and flow cytometry were applied to evaluate the effects of graphene oxide (GO) nanosheets on viability of cells. Apoptosis and cell cycle were analyzed by flow cytometry.Results: The results of this study showed that GO disturbed the cell cycle and nGO impaired cell viability by inducing cell apoptosis. Interestingly, both nGO and mGO blocked the cell cycle in the S phase, which is a critical phase of the cell cycle. Upregulation of TP53-gene transcripts was also detected in both nGO- and mGO-treated cells compared to the control, especially at 200 μg/mL. DNA content of the treated cells increased; however, because of DNA degradation, its quality was decreased.Conclusion: In conclusion, graphene oxide at both nano- and micro-scale damages cell physiology and increases cell population in the S phase of the cell cycle.Keywords: apoptosis, cell cycle, fibroblast cell, graphene, TP53 gene

Recently, modulation of the energy bandgap of graphene when gas molecules are adsorbed to its surface has been proved to be possible. Motivated by this, based on numerical calculations, we investigate the effect of the associated bandgap opening in graphene's spectrum on the sensing properties of the Faraday rotation (FR) of linearly polarized electromagnetic modes in a 1D photonic graphene-based sensor with a microcavity defect channel covered by two graphene layers. Our proposed model introduces an optical contact-free mechanism for the detection of low-concentration molecules attached to graphene's surface. We also show that FR angles could reveal reversal signs for a different amount of surface transfer doping.

Akram Assali,1 Omid Akhavan,2 Fatemeh Mottaghitalab,1 Mohsen Adeli,3 Rassoul Dinarvand,1 Shayan Razzazan,4 Ehsan Arefian,5 Masoud Soleimani,6 Fatemeh Atyabi1 1Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 2Department of Physics, Sharif University of Technology, Tehran, Iran; 3Department of Biology, Chemistry, Pharmacy, Institute of Chemistry and Biochemistry, Freie University Berlin, Berlin, Germany; 4Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran; 5Molecular Virology Lab, Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran; 6Hematology Department, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Introduction: MicroRNA-101 (miR-101) is an intense cancer suppressor with special algorithm to target a wide range of pathways and genes which indicates the ability to regulate apoptosis, cellular stress, metastasis, autophagy, and tumor growth. Silencing of some genes such as Stathmin1 with miR-101 can be interpreted as apoptotic accelerator and autophagy suppressor. It is hypothesized that hybrid microRNA (miRNA) delivery structures based on cationized graphene oxide (GO) could take superiority of targeting and photothermal therapy to suppress the cancer cells.Materials and methods: In this study, GO nanoplatforms were covalently decorated with polyethylene glycol (PEG) and poly-L-arginine (P-L-Arg) that reduced the surface of GO and increased the near infrared absorption ~7.5-fold higher than nonreduced GO.Results: The prepared nanoplatform [GO-PEG-(P-L-Arg)] showed higher miRNA payload and greater internalization and facilitated endosomal scape into the cytoplasm in comparison with GO-PEG. Furthermore, applying P-L-Arg, as a targeting agent, greatly improved the selective transfection of nanoplatform in cancer cells (MCF7, MDA-MB-231) in comparison with immortalized breast cells and fibroblast primary cells. Treating cancer cells with GO-PEG-(P-L-Arg)/miR-101 and incorporating near infrared laser irradiation induced 68% apoptosis and suppressed Stathmin1 protein.Conclusion: The obtained results indicated that GO-PEG-(P-L-Arg) would be a suitable targeted delivery system of miR-101 transfection that could downregulate autophagy and conduct thermal stress to activate apoptotic cascades when combined with photothermal therapy. Keywords: miR-101, cationized graphene oxide, poly-L-arginine, apoptosis, autophagy, photothermal therapy

In a recent paper, Struyve et al. [Struyve W, De Baere W, De Neve J and De Weirdt S 2003 J. Phys. A 36 1525] attempted to show that the thought experiment proposed in [Golshani M and Akhavan O 2001 J. Phys. A 34 5259, quant-ph/0103101] cannot distinguish between standard and Bohmian quantum mechanics. Here, we want to show that, in spite of their objection, our conclusion still holds out., Comment: 4 pages, no figures, Latex

The significance of proposals that can predict different results for standard and Bohmian quantum mechanics have been the subject of many discussions over the years. Here, we suggest a particular experiment (a two double-slit experiment) and a special detection process, that we call selective detection, to distinguish between the two theories. Using our suggested experiment, it is shown that the two theories predict different observable results at the individual level for a geometrically symmetric arrangement. However, their predictions are the same at the ensemble level. On the other hand, we have shown that at the statistical level, if we use our selective detection, then either the predictions of the two theories differ or where standard quantum mechanics is silent or vague, Bohmian quantum mechanics makes explicit predictions., 9 pages, 1 figure

Recently, three experiments have been proposed in order to show that the standard and Bohmian quantum mechanics can have different predictions at the individual level of particles. However, these thought experiments have encountered some objections. In this work, it is our purpose to show that our basic conclusions about those experiments are still intact., Comment: 8 pages, no figures, Revtex

In this investigation, we have considered two thought experiments to make a comparison between predictions of the standard and the Bohmian quantum mechanics. Concerning this, a two-particle system has been studied at two various situations of the entangled and the unentangled states. In the first experiment, the two theories can predict different results at the individual level, while their statistical results are the same. In the other experiment, not only they are in disagreement at the individual level, but their equivalence at the statistical level also breaks down, if one uses selective detection. Furthermore, we discuss about some objections that can be raised against the results of the two suggested experiments., Comment: 11 pages, 3 figure, Latex

In this investigation, we have suggested a special two-slit experiment which can distinguish between the standard and the Bohmian quantum mechanics. At the first step, we have shown that observable individual predictions obtained from these two theories are inconsistent for a special case. But, at the ensemble level, they are consistent as was expected. Then, as another special case and using selective detection, it is shown that an observable disagreement between the two theories can exist at the ensemble level of particles. This can encourage new efforts for finding other inconsistencies between the two theories, theoretically and experimentally., 5 pages, RevTex, no figures