Photothermal optical coherence tomography in ex vivo human breast tissues using gold nanoshells

We demonstrate photothermal optical coherence tomography (OCT) imaging in highly scattering human breast tissue ex vivo. A 120 kHz axial scan rate, swept-source phase-sensitive OCT system at 1300 nm was used to detect phase changes induced by 830 nm photothermal excitation of gold nanoshells. Localized phase modulation was observed 300–600 μm deep in scattering tissue using an excitation power of only 22 mW at modulation frequencies up to 20 kHz. This technique enables integrated structural and molecular-targeted imaging for cancer markers using nanoshells.National Institutes of Health (U.S.) (Grant Number R01- CA75289-13)United States. Air Force Office of Scientific Research (Contract Number FA9550-07-1-0014)MFELP (Contract Number FA9550-07-1-0101)Natural Sciences and Engineering Research Council of Canada (NSERC) Heritage Scholarship FundCenter for Integration of Medicine and Innovative TechnologyNational Science council of Taiwan. Taiwan Merit Scholarshi

Recent Results on Strangeness Production at RHIC

Due to its large acceptance, the STAR experiment has acquired a wealth of data on strangeness production for a variety of collisions systems and energies, from p+p to Au+Au. By using the yields and spectra, we address the evolution of the bulk system, including strangeness enhancement and the flavour dependence of radial and elliptic flow. Utilising the fact that we can identify strange baryons and mesons, we investigate different hadronization mechanisms in the intermediate and high p$_{T}$ regions. The ratios of the particle yields, measured to high p$_{T}$, are used to further investigate the range and applicability of the previously reported anomalous baryon production. We also study two-particle azimuthal correlations of identified particles in order to investigate any flavour dependence of jet fragmentation in the available p$_{T}$ range. Data was presented for a number of different collision systems and energies.Comment: Proceedings of SQM'06 Conference, LA, 2006 (submitted to J. Phys. G

Automated Segmentation of Intraretinal Cystoid Fluid in Optical Coherence Tomography

Cystoid macular edema (CME) is observed in a variety of ocular disorders and is strongly associated with vision loss. Optical coherence tomography (OCT) provides excellent visualization of cystoid fluid, and can assist clinicians in monitoring the progression of CME. Quantitative tools for assessing CME may lead to better metrics for choosing treatment protocols. To address this need, this paper presents a fully automated retinal cyst segmentation technique for OCT image stacks acquired from a commercial scanner. The proposed method includes a computationally fast bilateral filter for speckle denoising while maintaining CME boundaries. The proposed technique was evaluated in images from 16 patients with vitreoretinal disease and three controls. The average sensitivity and specificity for the classification of cystoid regions in CME patients were found to be 91% and 96%, respectively, and the retinal volume occupied by cystoid fluid obtained by the algorithm was found to be accurate within a mean and median volume fraction of 1.9% and 0.8%, respectively

Global Burden of HIV among Men Who Engage in Transactional Sex: A Systematic Review and Meta-Analysis

Background: Men who engage in transactional sex, the exchange of sex for money, goods, or other items of value, are thought to be at increased risk of HIV, but there have been no systematic attempts to characterize HIV burden in this population. We undertook a systematic review and meta-analysis to quantify the burden in this population compared with that of men in the general population to better inform future HIV prevention efforts. Methods: We searched seven electronic databases, national surveillance reports, and conference abstracts for studies of men who engage in transactional sex published between 2004–2013. Random effects meta-analysis was used to determine pooled HIV prevalence and prevalence ratios (PR) for the difference in HIV prevalence among men who engage in transactional sex as compared to general population men. Findings: Of 66 studies included representing 31,924 men who had engaged in transactional sex in 28 countries, pooled biological assay-confirmed HIV prevalence was 10.5% (95% CI = 9.4 to 11.5%). The highest pooled HIV prevalence was in Sub-Saharan Africa (31.5%, 95% CI = 21.6 to 41.5%), followed by Latin America (19.3%, 95% CI = 15.5 to 23.1%), North America (16.6%, 95% CI = 3.7 to 29.5%), and Europe (12.2%, 95% CI = 6.0 to 17.2%). Men who engaged in transactional sex had an elevated burden of HIV compared to the general male population (PR = 20.7, 95% CI = 16.8 to 25.5). Conclusions: The global burden of HIV is disproportionately high among men who engage in transactional sex compared with the general male population. There is an urgent need to include this population in systematic surveillance as well as to scale-up access to quality HIV prevention programs

On the development of MP-TOUGH2

The authors are developing MP-TOUGH2 for exploiting massively parallel computers. The goals of this effort are to (1) create a data-parallel subsurface transport code for solving larger problems than currently practical on workstations, (2) write portable code that can take advantage of scalability to run on machines with more processors, and (3) minimize the necessity for additional validation and verification of the resulting code. The initial strategy they have followed is to focus on optimizing the generic and time-consuming task of linear equation solution while leaving the bulk of TOUGH2 unmodified. In so doing, they have implemented a massively parallel direct solver (MPDS) that takes advantage of the banded structure of TOUGH2 Jacobian matrices. The authors have compared timings of the iterative conjugate gradient solvers DSLUBC, DSLUCS, and DSLUGM written in Fortran77 for the front end with the MPDS which uses the data parallel unit. The MPDS shows good performance relative to the iterative conjugate gradient solvers on the free-convection test problem. The robust direct solution provided by MPDS can be used to (1) check on the veracity of a given iterative conjugate gradient solution, or (2) be used on certain problems where iterative solvers fail to converge. The test problem used in this study is the Elder pure thermal convection problem. For generality, the authors use the TOUGH2 equation of state module EOS3 for water, air, and heat, although this particular problem is a single-phase flow problem

Eddy covariance observations of surface leakage during shallow subsurface CO2 releases

We tested the ability of eddy covariance (EC) to detect, locate, and quantify surface CO{sub 2} flux leakage signals within a background ecosystem. For 10 days starting on 07/09/2007, and for seven days starting on 08/03/2007, 0.1 (Release 1) and 0.3 (Release 2) t CO{sub 2}d{sup -1}, respectively, were released from a horizontal well {approx}100 m in length and {approx}2.5 m in depth located in an agricultural field in Bozeman, MT. An EC station measured net CO{sub 2} flux (F{sub c}) from 06/08/2006 to 09/04/2006 (mean and standard deviation = -12.4 and 28.1 g m{sup -2} d{sup -1}, respectively) and from 05/28/2007 to 09/04/2007 (mean and standard deviation = -12.0 and 28.1 g m{sup -2} d{sup -1}, respectively). The Release 2 leakage signal was visible in the F{sub c} time series, whereas the Release 1 signal was difficult to detect within variability of ecosystem fluxes. To improve detection ability, we calculated residual fluxes (F{sub cr}) by subtracting fluxes corresponding to a model for net ecosystem exchange from F{sub c}. F{sub cr} had reduced variability and lacked the negative bias seen in corresponding F{sub c} distributions. Plotting the upper 90th percentile F{sub cr} versus time enhanced the Release 2 leakage signal. However, values measured during Release 1 fell within the variability assumed to be related to unmodeled natural processes. F{sub cr} measurements and corresponding footprint functions were inverted using a least-squares approach to infer the spatial distribution of surface CO{sub 2} fluxes during Release 2. When combined with flux source area evaluation, inversion results roughly located the CO{sub 2} leak, while resolution was insufficient to quantify leakage rate

Reference materials (RMs) for analysis of the human factor II (prothrombin) gene G20210A mutation

The Scientific Committee of Molecular Biology Techniques (C-MbT) in Clinical Chemistry of the IFCC has initiated a joint project in co-operation with the European Commission, Joint Research Centre, Institute of Reference Materials and Measurements to develop and produce plasmid-type reference materials (RMs), for the analysis of the human prothrombin gene G20210A mutation. Although DNA tests have a high impact on clinical decision-making and the number of tests performed in diagnostic laboratories is high, issues of quality and quality assurance exist, and currently only a few RMs for clinical genetic testing are available. A gene fragment chosen was produced that spans all primer annealing sites published to date. Both the wild-type and mutant alleles of this gene fragment were cloned into a pUC18 plasmid and two plasmid RMs were produced. In addition, a mixture of both plasmids was produced to mimic the heterozygous genotype. The present study describes the performance of these reference materials in a commutability study, in which they were tested by nine different methods in 13 expert laboratories.. This series of plasmid RMs are, to the best of our knowledge, the first plasmid-type clinical genetic RMs introduced worldwide

Mathematical modeling of permeation grouting and subsurface barrier performance

The injection of solution grouts into the subsurface can be used to form underground barriers for the containment of contaminants. The technology requires identifying suitable grout materials, specifically fluids which exhibit a large increase in viscosity after injection and eventually solidify after a controllable period, thus sealing permeable zones. The authors have developed a new fluid property module for the reservoir simulator TOUGH2 to model grout injection, taking into account the increase of liquid viscosity as a function of time and gel concentration. They have also incorporated into the simulator a model which calculates soil hydraulic properties after solidification of the gel within the pore space. The new fluid property module has been used to design and analyze laboratory experiments and field pilot tests in saturated and unsaturated formations under a variety of subsurface conditions. These applications include modeling barrier emplacement in highly heterogeneous soils in the vadose zone, grout injection into the saturated zone in combination with extraction wells for flow control, the design of verification strategies, and the analysis of barrier performance. In this paper the authors discuss the modeling approach and present simulation results of multiple grout injections into a heterogeneous, unsaturated formation

Syphilis in the Americas: a protocol for a systematic review of syphilis prevalence and incidence in four high-risk groups, 1980–2016

Background: Syphilis infection has recently resurfaced as a significant public health problem. Although there has been a tremendous amount of research on the epidemiology of syphilis, there has been limited work done to synthesize the extensive body of research and systematically estimate patterns of disease within high-risk groups in the Americas. The purpose of this systematic review and meta-analysis is to (1) summarize recent patterns of syphilis infection in North and South America among four high-risk groups (MSM, transgender women, sex workers, and incarcerated individuals) from 1980 to 2016, (2) identify and differentiate regional geographic epidemiologic characteristics, and (3) compare the epidemics of the economically developed countries of North America from the developing countries and public health systems of Latin America and the Caribbean. Methods/design: Primary studies reporting syphilis prevalence and/or incidence in at least one of the four high-risk groups will be identified from Medline/PubMed, Embase, Lilacs, SciELO, The Cochrane Library, Web of Science, Scopus, ProQuest, CINAHL, Clase, and Periódica, as well as "gray" literature sources (conference abstracts, country reports, etc.). Studies published from 1980 through 2016 will be included. Data will be extracted from studies meeting inclusion and exclusion criteria and a random effects meta-analysis of prevalence and incidence estimates will be conducted. Heterogeneity, risk of bias, and publication bias will be assessed. Pooled prevalence and incidence estimates will be calculated for comparisons based on geographic region, risk factors, and time period. Discussion: Our systematic review and meta-analysis aims to contribute to an improved understanding of global epidemiologic patterns of syphilis infection in most-at-risk populations. Through systematic classification of the existing literature, and comparison of disease patterns across regional, temporal and socio-behavioral differences, we hope to improve public health surveillance and improve efforts to control the spread of disease across the Americas. Systematic review registration: PROSPERO CRD42016047306.Revisión por pare

A Hedged Monte Carlo Approach to Real Option Pricing

In this work we are concerned with valuing optionalities associated to invest or to delay investment in a project when the available information provided to the manager comes from simulated data of cash flows under historical (or subjective) measure in a possibly incomplete market. Our approach is suitable also to incorporating subjective views from management or market experts and to stochastic investment costs. It is based on the Hedged Monte Carlo strategy proposed by Potters et al (2001) where options are priced simultaneously with the determination of the corresponding hedging. The approach is particularly well-suited to the evaluation of commodity related projects whereby the availability of pricing formulae is very rare, the scenario simulations are usually available only in the historical measure, and the cash flows can be highly nonlinear functions of the prices.Comment: 25 pages, 14 figure