Molecular mechanisms controlling functional bacterial chromosome (nucleoid) compaction and organization are surprisingly enigmatic but partly depend on conserved, histone-like proteins HUαα and HUαβ and their interactions that span the nanoscale and mesosc

A new methodology based on tensor algebra that uses a higher order singular value decomposition to perform three-dimensional voxel reconstruction from a series of temporal images obtained using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is proposed. Principal component analysis (PCA) is used to robustly extract the spatial and temporal image features and simultaneously de-noise the datasets. Tumour segmentation on enhanced scaled (ES) images performed using a fuzzy C-means (FCM) cluster algorithm is compared with that achieved using the proposed tensorial framework. The proposed algorithm explores the correlations between spatial and temporal features in the tumours. The multi-channel reconstruction enables improved breast tumour identification through enhanced de-noising and improved intensity consistency. The reconstructed tumours have clear and continuous boundaries; furthermore the reconstruction shows better voxel clustering in tumour regions of interest. A more homogenous intensity distribution is also observed, enabling improved image contrast between tumours and background, especially in places where fatty tissue is imaged. The fidelity of reconstruction is further evaluated on the basis of five new qualitative metrics. Results confirm the superiority of the tensorial approach. The proposed reconstruction metrics should also find future applications in the assessment of other reconstruction algorithms.

Abstract: Background: In addition to being a strong risk factor for breast cancer, data from recent studies suggests that breast density changes correlate with response to preventative or adjuvant tamoxifen treatment for breast cancer. Breast density may be a surrogate biomarker for survival and indication of the need for additional treatments such as radiotherapy. However, quantitative methods to assess breast density in the clinic are limited. In this study, we assess how Diffuse Optical Spectroscopic Imaging (DOSI) may be used to evaluate and understand changes in breast density in patients undergoing neoadjuvant chemotherapy. Methods: DOSI was used to measure hemodynamic and metabolic information from the contralateral normal breast of 28 breast cancer patients undergoing neoadjuvant chemotherapy. DOSI uses near-infrared light to determine absolute tissue molar concentrations of oxyhemoglobin (ctO2Hb), deoxyhemoglobin (ctHHb), water, and lipid content without requirement of an exogenous contrast agent. DOSI measurements were compared to 3.0T MRI measured fibroglandular density before and during therapy. Results: Water (r = 0.843; P<0.001), ctHHb (r = 0.785; P = 0.003), and lipid (r = -0.707; P = 0.010) concentration measured with DOSI correlated strongly with MRI-measured density before therapy. During neoadjuvant treatment measured at ∼90 days after treatment commenced, significant reductions were observed in ctO2Hb for pre- (-20.0%; 95% confidence interval (CI), -32.7 to -7.4) and postmenopausal subjects (-20.1%; 95% CI, -31.4 to -8.8), and water concentration for premenopausal subjects (- 1.9%; 95% CI, -17.1 to -6.7) compared to baseline. Lipid content increased slightly in premenopausal subjects (3.8%; 95% CI, 1.1 to 6.5) and water increased slightly in postmenopausal subjects (4.4%; 95% CI, 0.1 to 8.6). Percentage change in water at the end of therapy compared with baseline correlated strongly with percentage change in MRI-measured density (r = 0.864; P = 0.012). Discussion: For this patient cohort, non-invasive optical measurement may provide an assessment of breast density and yield additional information that complements MRI and mammography techniques. We demonstrate a strong baseline correlation between water and ctHHb with breast density, reflecting the increased water content and rate of metabolism in fibroglandular breast tissue. Significant changes in optical markers for vascular density and supply (ctO2Hb and water) are observed during treatment. A significant decrease in ctO2Hb is observed in both menopausal groups. The steady reduction of ctO2Hb without a corresponding decrease in ctHHb suggests that chemotherapy agents act directly on the normal breast tissue, perhaps by causing a reduction of perfusion. The greater reduction in breast-tissue water in premenopausal subjects suggests that chemo-reduced ovarian hormone levels may exert a role in reducing breast-tissue density. Although from a limited patient dataset, these results suggest that DOSI may provide new functional indices of breast density based on hemoglobin and water that could be used at the bedside to assess response to therapy. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-01-12.

We report the measurement of Gamma and Gamma bar yields and inverse slope parameters in d+Au collisions at sqrt sNN = 200 GeV at forward and backward rapidities (y = +-2.75), using data from the STAR forward time projection chambers. The contributions of different processes to baryon transport and particle production are probed exploiting the inherent asymmetry of the d+Au system. Comparisons to model calculations show that baryon transport on the deuteron side is consistent with multiple collisions of the deuteron nucleons with gold participants. On the gold side, HIJING-based models without a hadronic rescattering phase do not describe themeasured particle yields, while models that include target remnants or hadronic rescattering do. The multichain model can provide a good description of the net baryon density in d+Au collisions at energies currently available at the BNL Relativistic Heavy Ion Collider, and the derived parameters of the model agree with those from nuclear collisions at lower energies.

We report on the observed differences in production rates of strange and multistrange baryons in Au+Au collisions at sqrt sNN = 200 GeV compared to p+p interactions at the same energy. The strange baryon yields in Au+Au collisions, when scaled down by the number of participating nucleons, are enhanced relative to those measured in p+p reactions. The enhancement observed increases with the strangeness content of the baryon, and it increases for all strange baryons with collision centrality. The enhancement is qualitatively similar to that observed at the lower collision energy sqrt sNN = 17.3 GeV. The previous observations are for the bulk production, while at intermediate pT , 1 < pT < 4 GeV/c, the strange baryons even exceed binary scaling from p+p yields.

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C. Please note that version 3 on the archive is the auxiliary version of the Physics of the B Factories book. This uses the notation alpha, beta, gamma for the angles of the Unitarity Triangle. The nominal version uses the notation phi_1, phi_2 and phi_3. Please cite this work as Eur. Phys. J. C74 (2014) 3026.