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We present an in situ calibration technique for the LBNL positron emission mammography (PEM) detector module that is capable of measuring depth of interaction (DOI). The detector module consists of 64 LSO crystals coupled on one end to a single photomultiplier tube (PMT) and on the opposite end to a 64 pixel array of silicon photodiodes (PD). The PMT provides an accurate timing pulse, the PDs identify the crystal of interaction, the sum provides a total energy signal and the /spl Gamma/=PD/(PD+PMT) ratio determines the depth of interaction. We calibrate using the /sup 176/Lu natural background radiation of the LSO crystals. We determine the relative gain (K) of the PMT and PD by minimizing the asymmetry of the /spl Gamma/ distribution. We determine the depth dependence from the width of the /spl Gamma/ distribution with optimal K. The performance of calibrated detector modules is evaluated by averaging results from 12 modules. The energy resolution is a function of depth ranging from 24 percent FWHM at the PD end to 51 percent FWHM at the PMT end, and the DOI resolution ranges from 6 mm FWHM at the PD end to 11 mm FWHM at the PMT end.

Many diffraction and imaging techniques have been developed and used to measure the strains in epitaxial films with different degrees of accuracy. In this tutorial, we will focus on measurements of strains in epitaxial films using electron diffraction techniques. These include reflection high-energy electron diffraction (RHEED), azimuthal reflection high-energy electron diffraction, low-energy electron diffraction (LEED), and high-resolution low-energy electron diffraction techniques. These diffraction techniques are surface sensitive and are suitable for in situ measurements of strains in ultrathin epitaxial films quantitatively. In particular, RHEED and LEED are simple to operate and readily available in many laboratories. We discuss the instrument limit of strain measurement in each technique. A nominal definition of the resolving power of an instrument to resolve a strain state is given as the percentage of intrinsic instrumental broadening in the reciprocal unit with respect to the first reciprocal Brillouin zone (2π/lattice constant) of a sample. It is shown that the resolving power of these diffraction techniques ranges from 2% to 0.2%. Experimental strategies without modifying the instrument and to achieve a strain detection capability beyond the definition of the nominal resolving power of these techniques are presented. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Lung adenocarcinoma (LUAD) is one of the most common cancers in the world. Protein regulator of cytokinesis 1 (PRC1) plays a role in the tumorigenesis and development of several cancers, including LUAD. The aim of the present study is to assess the characteristics of PRC1 in LUAD in order to find a potential drug that targets PRC1. MATERIALS AND METHODS: We investigated the prognostic value of PRC1 in patients with LUAD using Cox analysis of the RNA sequencing data from The Cancer Genome Atlas (TCGA) portal. A link between PRC1 and LUAD progression, cigarette smoking mutation count, aneuploidy, and hypoxia scores was assessed. The relationship between PRC1 and tumor-infiltrating immune cells in LUAD was analyzed and Gene Set Enrichment Analysis (GSEA) was used to study the PRC1-related biological process and signal pathways. Potential drugs targeting PRC1 were identified using DrugBank database and molecular docking. RESULTS: PRC1 expression was significantly increased in LUAD. PRC1 could be, therefore, a prognostic biomarker for predicting overall survival in LUAD. PRC1 expression was also related to cancer stage and patient’s smoking history. PRC1 positively correlated with mutation count, aneuploidy and hypoxia scores. It was also significantly related to tumor-infiltrating immune cells, especially the activated mast cells. GSEA revealed that PRC1 might be correlated with cell cycle, cytokinesis and p53 signaling pathway. Additionally, fostamatinib was found to be a potential drug targeting PRC1. CONCLUSIONS: PRC1 may have a prognostic value for patients with LUAD, and be correlated with the mutation count, aneuploidy, hypoxia and tumor-infiltrating immune cells. Fostamatinib was found to be a potential drug targeting PRC1 in LUAD. [ABSTRACT FROM AUTHOR]

To date, many materials have been successfully grown on substrates through van der Waals epitaxy without adhering to the constraint of lattice matching as is required for traditional chemical epitaxy. However, for elemental semiconductors such as Ge, this has been challenging and therefore it has not been achieved thus far. In this paper, we report the observation of Ge epitaxially grown on mica at a narrow substrate temperature range around 425 °C. Despite the large lattice mismatch (23%) and the lack of high in-plane symmetry in the mica surface, an epitaxial Ge film with [111] out-of-plane orientation is observed. Crystallinity and electrical properties degrade upon deviation from the ideal growth temperature, as shown by Raman spectroscopy, X-ray diffraction, and Hall effect measurements. X-ray pole figure analysis reveals that there exist multiple rotational domains in the epitaxial Ge film with dominant in-plane orientations between Ge[110] and mica[100] of (20n)°, where n=0, 1, 2, 3, 4, 5. A superlattice area mismatch model was used to account for the likelihood of the in-plane orientation formation and was found to be qualitatively consistent with the observed dominant orientations. Our observation of Ge epitaxy with one out-of-plane growth direction through van der Waals forces is a step toward the growth of single crystal Ge films without the constraint in the lattice and symmetry matches with the substrates. [ABSTRACT FROM AUTHOR]