Effect of uniaxial strain on plasmon excitations in graphene

Uniaxial strain is known to modify significantly the electronic properties of graphene, a carbon single layer of atomic width. Here, we study the effect of applied strain on the composite excitations arising from the coupling of charge carriers and plasmons in graphene, i.e. the plasmarons. Specifically, we predict that the plasmaron energy dispersion, which has been recently observed experimentally in unstrained graphene, is shifted and broadened by applied uniaxial strain. Thus, strain constitutes an additional parameter which may be useful to tune graphene properties in plasmaronic devices.Comment: Invited oral lecture at the 23rd AIRAPT International Conference on "High Pressure Science and Technology", Mumbai (India), September 25-30, 2011. To be published in J. Phys.: Conf. Series (2012

Deamidation at Asparagine and Glutamine As a Major Modification upon Deterioration/Aging of Proteinaceous Binders in MuralPaintings

Proteomic strategies are herein proved to be a complementary approach to the well established amino acid composition analysis for the characterization of the aging and deterioration phenomena occurring to proteinaceous materials in works-of-art. Amino acid analyses on several samples demonstrated that proteins in the frescoes from the Camposanto Monumentale in Pisa are deteriorated as revealed by the decrease in Met, Lys, and Tyr content and by the presence in all the samples of amino malonic acid as a result of Ser, Phe, and Cys oxidation. Proteomic analysis identified deamidation at Asn and Gln as a further major event occurred. This work paves the way to the exploitation of proteomic strategies for the investigation of the molecular effects of aging and deterioration in historical objects. Results show that proteomic searches for deamidation by liquid chromatography-tandem mass spectrometry (LC-MS/MS) could constitute a routine analysis for paintings or any artistic and historic objects where proteins are present. Peptides that can be used as molecular markers when casein is present were identified

Evaluation of epigenetic and radiomodifying effects during radiotherapy treatments in zebrafish

Radiotherapy is still a long way from personalizing cancer treatment plans, and its effective-ness depends on the radiosensitivity of tumor cells. Indeed, therapies that are efficient and successful for some patients may be relatively ineffective for others. Based on this, radiobiological research is focusing on the ability of some reagents to make cancer cells more responsive to ionizing radiation, as well as to protect the surrounding healthy tissues from possible side effects. In this scenario, zebrafish emerged as an effective model system to test for radiation modifiers that can potentially be used for radiotherapeutic purposes in humans. The adoption of this experimental organism is fully justified and supported by the high similarity between fish and humans in both their genome sequences and the effects provoked in them by ionizing radiation. This review aims to provide the literature state of the art of zebrafish in vivo model for radiobiological studies, particularly focusing on the epigenetic and radiomodifying effects produced during fish embryos’ and larvae’s exposure to radiotherapy treatments

Geotechnical and historical aspects on the collapse of the Tiber embankment walls in the centre of Roma (1870–1900)

This paper deals with the issues related to the construction of the Tiber’s embankment walls between years 1870–1926. The embankment walls (muraglioni) were designed by Raffaele Canevari to mitigate the effects of the river inundation in the city centre of Roma. After the flood of December 1900, several portions of the Anguillara and Alberteschi sections collapsed. The aim of this work is to investigate whether the causes of the collapse can be traced back to design approaches of the time, lacking from a point of view of the hydro-mechanical interaction of the soil in the evaluation of the total earth pressure. In particular, designed calculations are also revised accounting for more advance soil phenomena laws, based on Terzaghi effective stress and the effects of scouring and erosion. Some assumptions have been made on the mechanical characteristics of the backfill soils and on the relying on foundation materials

Proteomic patterns of cultured breast cancer cells and epithelial mammary cells.

Breast cancer is one of the leading causes of death from cancer among women in western countries. The different types of breast cancer are grouped into invasive and noninvasive forms. Among the invasive types, ductal infiltrating carcinoma (DIC) is the most common and aggressive form. Using an in vitro model consisting of a DIC-derived cell line (8701-BC) and a nontumoral mammary epithelial cell line (HB2), we used the proteomics approach to search for homology and differences in protein expression patterns between tumoral and nontumoral phenotypes. Within an analysis window comprising 1,750 discernible spots we have currently catalogued 140 protein spots of potential interest. Fifty-eight of them were identified by gel matching with reference maps, immunodetection, or N-terminal microsequencing and classified into four functional groups. Twelve proteins were found differentially expressed in two cell lines: four were uniquely present in the neoplastic cell proteome and eight in epithelial cells. In addition, 53 proteins displayed different relative expression levels between the two cell lines, that is, 44 were more elevated in cancer cells and 9 in HB2 cells. Among proteins with greater relative abundance in cancer cells we identified glycolytic enzymes (or their isoforms), which may indicate that the known metabolic dysregulation in cancer can reflect oncogenic-related defects of glycolytic gene expression

Generalised multistage modelling and tuning algorithm for class EF and class Φ inverters to eliminate iterative retuning

The additional complexity of Class EF and Class Φ inverters compared to their Class E counterparts, combined with parasitic effects becoming more prevalent as frequency and power levels increase, results in poor accuracy from traditional design methods, and usually additional iterations of manual retuning are required. In this work we propose an approach to simulating and tuning Class EF/Φ inverters, with various levels of accuracy depending on the level of knowledge of the system parasitics. Our method is comprised of a combination of analytic and numerical solving methods thus providing both insight on the progression of the algorithm and computational robustness. The aim of our algorithm formulation is to enable solutions to be found in an automated and fast way. The novelty in our work lies in the design method's concurrent capability to provide a generalised set of design inputs (e.g. DC to AC current gain, arbitrary drain voltage slope at turn on, Φ- branch resonance, etc.), inclusion of board and device non-linear parasitics, and the ability to design within the set of preferred component values. An example is shown for the design of a 50 W, 13.56 MHz inverter where the experimental setup approaches the theoretical efficiency of 97%. The algorithm changes the values of the components over 5% to 50% and improves the simulated waveform accuracy by 2 to 12 times compared to the design method based on first order approximations

Partial purification and MALDI-TOF MS analysis of UN1, a tumor antigen membrane glycoprotein.

UN1 is a membrane glycoprotein that is expressed in immature human thymocytes, a subpopulation of peripheral T lymphocytes, the HPB acute lymphoblastic leukemia (ALL) T-cell line and fetal thymus. We previously reported the isolation of a monoclonal antibody (UN1 mAb) recognizing the UN1 protein that was classified as "unclustered" at the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. UN1 was highly expressed in breast cancer tissues and was undetected in non-proliferative lesions and in normal breast tissues, indicating a role for UN1 in the development of a tumorigenic phenotype of breast cancer cells. In this study, we report a partial purification of the UN1 protein from HPB-ALL T cells by anion-exchange chromatography followed by immunoprecipitation with the UN1 mAb and MALDI-TOF MS analysis. This analysis should assist in identifying the amino acid sequence of UN

Integral equation for inhomogeneous condensed bosons generalizing the Gross-Pitaevskii differential equation

We give here the derivation of a Gross-Pitaevskii--type equation for inhomogeneous condensed bosons. Instead of the original Gross-Pitaevskii differential equation, we obtain an integral equation that implies less restrictive assumptions than are made in the very recent study of Pieri and Strinati [Phys. Rev. Lett. 91 (2003) 030401]. In particular, the Thomas-Fermi approximation and the restriction to small spatial variations of the order parameter invoked in their study are avoided.Comment: Phys. Rev. A (accepted