Prediction of Viral Loads for Diagnosis of Hepatitis C Infection in Human Plasma Samples Using Raman Spectroscopy Coupled with Partial Least Squares Regression Analysis

Raman spectroscopy has been used to identify the biochemical changes associated with the presence of the Hepatitis C virus (HCV) in infected human blood plasma samples as compared with healthy samples, as control. The aim of the study was to establish the Raman spectral markers of hepatitis infection, which could be used for diagnostic purposes. Moreover, multivariate data analysis techniques, including Principal Component Analysis (PCA), coupled with Linear Discriminant Analysis (LDA), and Partial Least Square Regression (PLSR) are employed to further demonstrate the diagnostic capability of the technique. The PLSR model is developed to predict the viral loads of the HCV infected plasma on the basis of the biochemical changes caused by the viral infection. Specific Raman spectral features are observed in the mean spectra of HCV plasma samples which are not observed in the control mean spectra. PCA differentiated the ‘normal’ and ‘HCV’ groups of the Raman spectra and PCA-LDA was employed to increase the efficiency of prediction of the presence of HCV infection, resulting in a sensitivity and specificity 98.8% and 98.6%, with corresponding Positive Predictive Value of 99.2%, and Negative Predictive Value of 98%. PLSR modelling was found to be 99% accurate in predicting the actual viral loads of the HCV samples, as determined clinically using the Polymerase Chain Reaction (PCR) technique, on the basis of the Raman spectral changes caused by the virus during the process of the development of Hepatitis C. Copyright © 2017 John Wiley & Sons, Ltd

Assessment of an osteoblast-like cell line as a model for human primary osteoblasts using Raman spectroscopy

Raman spectroscopy is employed to determine the suitability of the U20S osteoblast-like cell line for use as a model for human primary osteoblasts, with emphasis on the ability of these cell types to replicate their tissue of origin. It was found that both cell types demonstrated early stage mineral deposition that followed significantly different growth patterns. Analysis of the growth pattern and spectral data from primary cells revealed increasing bone quality ratios and a high crystallinity, consistent with previous reports. Conversely the investigation of the U20S osteoblast-like cell line provided evidence of dense multilayered mineralised regions that corresponded more closely to native bone in terms of its crystallinity and bone quality ratios. This finding contradicts previous reports on U20S osteoblast-like cells which have consistently described them as non-osteoinductive when cultured in various conditions on a number of substrates. This work demonstrates the successful application of Raman spectroscopy combined with biological and multivariate analysis for the investigation of osteoblast-like U20S cells and human primary osteoblasts, specifically with focus on the osteoinductive ability of the osteoblast-like cell line and the comparative differences in relation to the primary osteoblasts

Variational Interpolation Algorithm between Weak- and Strong-Coupling Expansions

For many physical quantities, theory supplies weak- and strong-coupling expansions of the types $\sum a_n \alpha ^n$ and \alpha ^p\sum b_n (\alpha^{-2/q) ^n, respectively. Either or both of these may have a zero radius of convergence. We present a simple interpolation algorithm which rapidly converges for an increasing number of known expansion coefficients. The accuracy is illustrated by calculating the ground state energies of the anharmonic oscillator using only the leading large-order coefficient $b_0$ (apart from the trivial expansion coefficent $a_0=1/2$). The errors are less than 0.5 for all g. The algorithm is applied to find energy and mass of the Fr\"ohlich-Feynman polaron. Our mass is quite different from Feynman's variational approach.Comment: PostScript, http://www.physik.fu-berlin.de/kleinert.htm

Critical properties of Ising model on Sierpinski fractals. A finite size scaling analysis approach

The present paper focuses on the order-disorder transition of an Ising model on a self-similar lattice. We present a detailed numerical study, based on the Monte Carlo method in conjunction with the finite size scaling method, of the critical properties of the Ising model on some two dimensional deterministic fractal lattices with different Hausdorff dimensions. Those with finite ramification order do not display ordered phases at any finite temperature, whereas the lattices with infinite connectivity show genuine critical behavior. In particular we considered two Sierpinski carpets constructed using different generators and characterized by Hausdorff dimensions d_H=log 8/log 3 = 1.8927.. and d_H=log 12/log 4 = 1.7924.., respectively. The data show in a clear way the existence of an order-disorder transition at finite temperature in both Sierpinski carpets. By performing several Monte Carlo simulations at different temperatures and on lattices of increasing size in conjunction with a finite size scaling analysis, we were able to determine numerically the critical exponents in each case and to provide an estimate of their errors. Finally we considered the hyperscaling relation and found indications that it holds, if one assumes that the relevant dimension in this case is the Hausdorff dimension of the lattice.Comment: 21 pages, 7 figures; a new section has been added with results for a second fractal; there are other minor change

A strong-coupling analysis of two-dimensional O(N) sigma models with N≥3N\geq 3 on square, triangular and honeycomb lattices

Recently-generated long strong-coupling series for the two-point Green's functions of asymptotically free ${\rm O}(N)$ lattice $\sigma$ models are analyzed, focusing on the evaluation of dimensionless renormalization-group invariant ratios of physical quantities and applying resummation techniques to series in the inverse temperature $\beta$ and in the energy $E$. Square, triangular, and honeycomb lattices are considered, as a test of universality and in order to estimate systematic errors. Large-$N$ solutions are carefully studied in order to establish benchmarks for series coefficients and resummations. Scaling and universality are verified. All invariant ratios related to the large-distance properties of the two-point functions vary monotonically with $N$, departing from their large-$N$ values only by a few per mille even down to $N=3$.Comment: 53 pages (incl. 5 figures), tar/gzip/uuencode, REVTEX + psfi

Universality of low-energy scattering in (2+1) dimensions

We prove that, in (2+1) dimensions, the S-wave phase shift, $\delta_0(k)$, k being the c.m. momentum, vanishes as either $\delta_0 \to {c\over \ln (k/m)} or \delta_0 \to O(k^2)$ as $k\to 0$. The constant $c$ is universal and $c=\pi/2$. This result is established first in the framework of the Schr\"odinger equation for a large class of potentials, second for a massive field theory from proved analyticity and unitarity, and, finally, we look at perturbation theory in $\phi_3^4$ and study its relation to our non-perturbative result. The remarkable fact here is that in n-th order the perturbative amplitude diverges like $(\ln k)^n$ as $k\to 0$, while the full amplitude vanishes as $(\ln k)^{-1}$. We show how these two facts can be reconciled.Comment: 23 pages, Late

COVID-19-related stigma among infected people in Sweden; psychometric properties and levels of stigma in two cohorts as measured by a COVID-19 stigma scale

BACKGROUND: Epidemics have historically been accompanied by stigma and discrimination. Disease-related stigma has often been shown to have severe consequences for physical, mental and social wellbeing and lead to barriers to diagnosis, treatment and prevention. The aims of this study were to investigate if a HIV-related stigma measure could be adapted and valid and reliable to measure COVID-19-related stigma, and also to investigate levels of self-reported stigma and related factors among people in Sweden with experience of COVID-19 and compare levels of COVID-19-related stigma versus HIV-related stigma among persons living with HIV who had experienced a COVID-19 event. METHODS: Cognitive interviews (n = 11) and cross-sectional surveys were made after the acute phase of the illness using a new 12-item COVID-19 Stigma Scale and the established 12-item HIV Stigma Scale in two cohorts (people who had experienced COVID-19 (n = 166/209, 79%) and people living with HIV who had experienced a COVID-19 event (n = 50/91, 55%). Psychometric analysis of the COVID-19 Stigma Scale was performed by calculating floor and ceiling effects, Cronbach's α and exploratory factor analysis. Levels of COVID-19 stigma between groups were analysed using the Mann-Whitney U test. Levels of COVID-19 and HIV stigma among people living with HIV with a COVID-19 event were compared using the Wilcoxon signed-rank test. RESULTS: The COVID-19 cohort consisted of 88 (53%) men and 78 (47%) women, mean age 51 (19-80); 143 (87%) living in a higher and 22 (13%) in a lower income area. The HIV + COVID-19 cohort consisted of 34 (68%) men and 16 (32%) women, mean age 51 (26-79); 20 (40%) living in a higher and 30 (60%) in a lower income area. The cognitive interviews showed that the stigma items were easy to understand. Factor analysis suggested a four-factor solution accounting for 77% of the total variance. There were no cross loadings, but two items loaded on factors differing from the original scale. All subscales had acceptable internal consistency, showed high floor and no ceiling effects. There was no statistically significant difference between COVID-19 stigma scores between the two cohorts or between genders. People living in lower income areas reported more negative self-image and concerns about public attitudes related to COVID-19 than people in higher income areas (median score 3 vs 3 and 4 vs 3 on a scale from 3-12, Z = -1.980, p = 0.048 and Z = -2.023, p = 0.024, respectively). People from the HIV + COVID-19 cohort reported more HIV than COVID-19 stigma. CONCLUSIONS: The adapted 12-item COVID-19 Stigma Scale may be valid and reliable for measurement of COVID-19-related stigma. However, specific items may need to be rephrased or replaced to better correspond to the COVID-19 context. People who had experienced COVID-19 reported low levels of COVID-19-related stigma in general but people from lower income areas had higher levels of negative self-image and concerns about public attitudes related to COVID-19 than people from areas with higher income, which may call for targeted interventions. Although exhibiting more pronounced HIV stigma levels, people living with HIV who had experienced COVID-19 reported COVID-19-related stigma of the same low magnitude as their peers not living with HIV

Perspectives on Andean Prehistory and Protohistory: Papers from the Third Annual Northeast Conference on Andean Archaeology and Ethnohistory

This volume represents eight of the eighteen papers presented at the Third Northeast Conference on Andean Archaeology and Ethnohistory held at the University of Massachusetts, Amherst on October 27 and 28, 1984. It also includes a paper presented at the Second NCAAE held at the American Museum of Natural History on November 19-20, 1983. The papers include: Wandering Shellfish: New Insights from Southeastern Coastal Ecuador by Patricia Netherly, Late Prehistoric Terracing at Chijra in the Collca Valley, Peru: Preliminary Report I by Michael A. Malpass, The Topara Tradition: An Overview by Dwight T. Wallace, The Peruvian North Central Coast During the Early Intermediate Period: An Emerging Perspective by Richard E. Daggett, A Sequence of Monumental Architecture from Huamanchuco by John R. Topic, Duality in Public Architecture in the Upper Zena Valley by Patricia J. Netherly and Tom D. Dillehay, Piruru: A Preliminary Report on the Archaeological Botany of a Highland Andean Site by Lawrence Kaplan and Elisabeth Bonnier, Analysis of Organic Remains from Huamachuco Qollqas by Coreen E. Chiswell, Aspects of Casting Practice in Prehispanic Peru by Stuart V. Arnold, and Representations of the Cosmos: A Comparison of the Church of San Cristobal de Pampachiri with the Coricancha Drawing of Santacruz Pachacuti Yamqui Salcamaygua by Monica Barnes.https://digitalcommons.library.umaine.edu/andean_past_special/1000/thumbnail.jp

Frequency and genome load of Epstein-Barr virus in 509 breast cancers from different geographical areas

Since the few data exploring a possible association between Epstein–Barr virus (EBV) and breast cancer are conflicting, we investigated this association together with the influences of geographical areas. 509 breast cancers were sampled from areas with varying risks of nasopharynx carcinoma (NPC) such as North Africa (Algeria and Tunisia, high-risk area); southern France (Marseille, intermediate-risk area); and northern Europe (northern France, the Netherlands and Denmark; low-risk areas). Polymerase chain reaction (PCR) of a subregion of EBV BamHIC encoding the EBERs demonstrated that 31.8% of the tumours contained the viral genome. No significant differences were observed among the geographical areas. However, positive samples showed higher loads of the EBV genome in the NPC high- and intermediate-risk areas than in the low-risk areas. EBV type 1 was the dominant strain. In situ hybridization studies using a35S-labelled riboprobe for EBER1 and a laser capture microdissection, combined with quantitative PCR, showed that EBV localization was restricted to some tumour epithelial cell clusters. EBV could not be detected in the stroma. Considering the whole population covered, the presence of the EBV genome was not correlated with age, menopausal status, tumour, size, nodal status or histological grade. © 2001 Cancer Research Campaign http://www. bjcancer.co

Hormone replacement therapy before breast cancer diagnosis significantly reduces the overall death rate compared with never-use among 984 breast cancer patients

Nine hundred and eighty-four breast cancer patients were interviewed regarding exogenous hormonal use. This represents a random sample of breast cancer patients in Southern Sweden referred to the Department of Oncology at Lund for treatment between 1978 and 1997 (excluding 1980 and 1981) with a 100% follow-up. Ever-use of hormone replacement therapy (HRT) prior to diagnosis was significantly associated with a longer overall survival in women with their breast cancer diagnosed at ages 45 and above, relative risk (RR) of dying 0.73 (95% confidence interval (CI) 0.62-0.87; P = 0.0005). Ever use of HRT prior to breast cancer diagnosis was significantly positively associated with overall longer survival after adjustment for T-stage, N-stage, M-stage, year of diagnosis and age at diagnosis, RR of dying 0.78 (95% CI 0.65-0.93; P = 0.006). Hormone replacement therapy use and oestrogen receptor positivity were independently significantly associated with overall longer survival, P = 0.005 and P < 0.0001, respectively, in one model. HRT use and progesterone receptor positivity were also independently significantly associated with longer overall survival, P = 0.003 and P = 0.0003, respectively, in another model. The mode of diagnosis was known in 705 women. Mammography screening was not more common among HRT users compared with never-users, where this information was available. Both mammography screening and HRT use were independently associated with longer survival, P = 0.002 and P = 0.038 respectively