Recent years have witnessed many breakthroughs in research on graphene (the first two-dimensional atomic crystal) as well as a significant advance in the mass production of this material. This one-atom-thick fabric of carbon uniquely combines extreme mechanical strength, exceptionally high electronic and thermal conductivities, impermeability to gases, as well as many other supreme properties, all of which make it highly attractive for numerous applications. Here we review recent progress in graphene research and in the development of production methods, and critically analyse the feasibility of various graphene applications.

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A roadmap for graphene

A review of reported tissue optical properties summarizes the wavelength-dependent behavior of scattering and absorption. Formulae are presented for generating the optical properties of a generic tissue with variable amounts of absorbing chromophores (blood, water, melanin, fat, yellow pigments) and a variable balance between small-scale scatterers and large-scale scatterers in the ultrastructures of cells and tissues.

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Optical properties of biological tissues: a review.

We describe the landscape of somatic genomic alterations based on multidimensional and comprehensive characterization of more than 500 glioblastoma tumors (GBMs). We identify several novel mutated genes as well as complex rearrangements of signature receptors, including EGFR and PDGFRA. TERT promoter mutations are shown to correlate with elevated mRNA expression, supporting a role in telomerase reactivation. Correlative analyses confirm that the survival advantage of the proneural subtype is conferred by the G-CIMP phenotype, and MGMT DNA methylation may be a predictive biomarker for treatment response only in classical subtype GBM. Integrative analysis of genomic and proteomic profiles challenges the notion of therapeutic inhibition of a pathway as an alternative to inhibition of the target itself. These data will facilitate the discovery of therapeutic and diagnostic target candidates, the validation of research and clinical observations and the generation of unanticipated hypotheses that can advance our molecular understanding of this lethal cancer.

The somatic genomic landscape of glioblastoma

We review the field of femtosecond pulse shaping, in which Fourier synthesis methods are used to generate nearly arbitrarily shaped ultrafast optical wave forms according to user specification. An emphasis is placed on programmable pulse shaping methods based on the use of spatial light modulators. After outlining the fundamental principles of pulse shaping, we then present a detailed discussion of pulse shaping using several different types of spatial light modulators. Finally, new research directions in pulse shaping, and applications of pulse shaping to optical communications, biomedical optical imaging, high power laser amplifiers, quantum control, and laser-electron beam interactions are reviewed.

Femtosecond pulse shaping using spatial light modulators

Optical sensing of specific molecular targets and pathways deep inside living mice has become possible as a result of a number of advances. These include design of biocompatible near-infrared fluorochromes, development of targeted and activatable 'smart' imaging probes, engineered photoproteins and advances in photon migration theory and reconstruction. Together, these advances will provide new tools making it possible to understand more fully the functioning of protein networks, diagnose disease earlier and speed along drug discovery.

Shedding light onto live molecular targets

Urinary tract infection (UTI) diagnosis requires an overnight culture to identify a sample as positive or negative for a UTI. Additional cultures are required to identify the pathogen responsible for the infection and to test its sensitivity to antibiotics. A rise in ineffective treatment s, chronic infections, rising health car e costs and antibiotic resistance are some of the consequences of this prolonged waiting period of UTI diagnosis. In this work, Surface Enhanced Raman Spectroscopy (SERS) is used for classify ing bacterial samples as positive or negative for UTI. SERS spectra of serial dilutions of E.coli bacteria, isolated from a urine culture, were classified as positive (10 5 -10 8 cells/ml) or negative (10 3 -10 4 cells/ml) for UTI after mixing samples with gold nanoparticles. A leave-one-out cross validation was performed using the first two principal components resulting in the correct classification of 82% of all samples. Sensitivity of classification was 88% and specificity was 67%. Antibiotic sensitivity testing was also done using SERS spectra of various species of gram negative bacteria collected 4 hours after ex posure to antibiotics. Spectra l analysis revealed clear separation between the spectra of samples exposed to ciprofl oxacin (sensitive) and amoxicillin (resistant). This study can become the basis for identifying urine samples as positive or negative for a UTI and determining their antibiogram without requiring an overnight culture. Keywords: Surface Enhanced Raman Spectroscopy, bacteria, cla ssification, dilutions, nega tive, positive, antibiogram

Classification of bacterial samples as negative or positive for a UTI and antibiogram using surface enhanced Raman spectroscopy

Breast cancer is one of the most deadly malignancies worldwide and the second leading cause of death in women. Mammography, i.e. the screening for breast cancer with x-ray imaging, has significantly improved the prognosis of patients diagnosed with the disease. The evaluation of mammograms requires a panel of radiologists, but even well trained experts can err in their assessment. For this reason, Computer-Aided Detection (CAD) systems are becoming more prevalent. In this paper, we introduce a novel approach for breast Micro-Calcification (MC) diagnosis using temporal sequences of digital mammograms. The goal is to increase the MC detection accuracy by subtracting prior images. A new dataset, with precise marking of MC locations, was created specifically for this study. The proposed approach began with temporal subtraction of mammograms, after demon-based registration, which effectively removed unchanged regions and MCs (17.3% reduction in the number of MCs). The second step was the classification of the MCs as benign or suspicious using the subtracted images. A set of diverse features were selected for the classification. Four different classifiers were tested with leave-one-patient-out cross-validation. For comparison, the MC classification was also performed, using single mammograms, without temporal subtraction. The average accuracy of the classification of the MCs as benign or suspicious was 91.3% without and 99.2% with temporal subtraction using Support Vector Machines (statistically significant $\mathbf{p}=0.026$ ). These results show that temporal subtraction could be a valuable addition to CAD systems to assist radiologists in effectively detecting breast MCs.

A new method for breast micro-calcification detection and characterization using digital temporal subtraction of mammogram pairs

Using state of the art laser technology, in vivo optical coherence tomography imaging with unprecedented axial resolution of 1 um is achieved, approaching the level of conventional histopathology. With an extension of this technique, extraction of spatially resolved spectroscopic information is enabled to improve image contrast and to obtain functional or biochemical properties of the investigated tissue.

Ultrahigh resolution and spectroscopic optical coherence tomography

Antibiotic resistance is a major health care problem mostly caused by the inappropriate use of antibiotics. At the root of
the problem lies the current method for determination of bacterial susceptibility to antibiotics which requires overnight
cultures. Physicians suspecting an infection usually prescribe an antibiotic without waiting for the results. This practice
aggravates the problem of bacterial resistance. In this work, a rapid method of diagnosis and antibiogram for a bacterial
infection was developed using Surface Enhanced Raman Spectroscopy (SERS) with silver nanoparticles. SERS spectra
of three species of gram negative bacteria, Escherichia coli, Proteus spp., and Klebsiella spp. were obtained after 0 and 4
hour exposure to the seven different antibiotics. Even though the concentration of bacteria was low (2x105 cfu/ml),
species classification was achieved with 94% accuracy using spectra obtained at 0 hours. Sensitivity or resistance to
antibiotics was predicted with 81%-100% accuracy from spectra obtained after 4 hours of exposure to the different
antibiotics. With the enhancement provided by SERS, the technique can be applied directly to urine or blood samples,
bypassing the need for overnight cultures. This technology can lead to the development of rapid methods of diagnosis
and antibiogram for a variety of bacterial infections.

Urinary tract infection (UTI) multi-bacteria multi-antibiotic testing using surface enhanced Raman spectroscopy (SERS)

Optical coherence tomography (OCT) uses low-coherence interferometry to perform optical ranging measurements within biological tissue. Recent advances in OCT technology have permitted high-speed imaging at 4-8 frames/s. In vivo catheter/endoscope-based OCT imaging has recently been performed in a rabbit. OCT has also shown a feasibility for surgical diagnostics and for assessing microsurgical repairs of vessels and nerves. In this study, we investigate the use of high-speed OCT as an interventional imaging modality for surgical guidance. OCT can provide continuous image-guidance for the precise delivery of high-power laser radiation and selective ablation of diseased tissue.

Costas Pitris

Papers

Classification of bacterial samples as negative or positive for a UTI and antibiogram using surface enhanced Raman spectroscopy

A new method for breast micro-calcification detection and characterization using digital temporal subtraction of mammogram pairs

Ultrahigh resolution and spectroscopic optical coherence tomography

Urinary tract infection (UTI) multi-bacteria multi-antibiotic testing using surface enhanced Raman spectroscopy (SERS)

Interventional optical coherence tomography for surgical guidance