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This study aims to identify the role of tumor immune microenvironment in ductal carcinoma in situ (DCIS) in predicting risk of recurrence and benefit of whole breast irradiation (WBI). Different subtypes of tumor infiltrating lymphocytes (TILs), tumor associated macrophages (TAMs) and tertiary lymphoid structures (TLSs) were determined in tumor tissues of DCIS cohort who received breast-conserving surgery (BCS). All the TILs and TAMs subtypes were evaluated by the average numbers of touching-TILs/TAMs which defined as TILs/ TAMs touching or within one lymphocyte/macrophage cell thickness from the malignant ducts' basement membrane. In total, 165 patients were enrolled in this analysis with 113 patients received WBI. After a median follow-up of 73.7 months, 15 ipsilateral breast tumor recurrence (IBTR) events occurred with 6 invasive-IBTRs. Nine out of 15 IBTRs occurred outside of the original quadrant (elsewhere failure event, EFE). The univariate analyses showed that dense TILs subtype, TAMs and TLS were significantly associated with higher IBTR (all P <0.05). High ratios of CD4+/CD8+, Treg/CD4+ and Treg/CD8+ were also found to be prognostic factors for higher IBTR (all P <0.01). We then performed least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses to identify the variables associated with IBTR. The ER negative status, high ratios of CD4+/CD8+, dense CD68+ TAMs, sparse CD8+ T cell and dense mature TLS remained independent risk factors of IBTR (all P <0.05) to develop a nomogram. Points of nomogram were defined as immune microenvironment score (IMS) which divided all patients into low-, intermediate- and high-risk groups. Significant differences in IBTR existed among these three risk subgroups (5y-rate: 0.0% vs. 11.4% vs. 72.2%, P <0.01). For the whole cohort, the benefit of WBI was found only in the intermediate-risk subgroup (5y-rate of IBTR: 7.0% vs. 22.0%, P = 0.04). With respect to EFE, WBI also significantly reduced the rate from 16.4% to 2.3% (P = 0.01) in the intermediate-risk group while not in the low- and high-risk group. Assessment of overall immune cells subtypes provides a tool for comprehensive evaluation of the DCIS immune microenvironment. The benefit of WBI was only observed in the intermediate-risk group. Patients in the high-risk group showed an increased risk of IBTR regardless of the receipt of WBI. [ABSTRACT FROM AUTHOR]

Detailed transmission electron microscopy (TEM) investigations of the degree of delamination, crystallinity, microstructure, interface and surface structure, defects and chemical composition of nanosheets are reported. The effects of the present multiplex synthetic routine including ion exchange, intercalation and exfoliation processes are discussed.

Research describing the chemical valence of cerium ions incorporated in alpha-sialon is presented. In particular the electron energy loss spectra of cerium in different locations in the microstructure is examined.

High resolution analytical electron microscopy was used to characterize a cubic Si3N4 phase/nanostructure.

Zinc-blende-type face centred cubic structure GaP nanowires with Ga2O3 coating were synthesized by heating Ga2O3 and red phosphorus powder with the assistance of NH3 and Ar at 1323 K. The GaP/Ga2O3 nanowires have a uniform size distribution with diameters ranging from tens of nm to hundreds of nm and lengths up to several micrometres. The inner GaP nanowires have almost a single-crystal structure with twin defects and have the <111> direction as preferential growth direction. Outer Ga2O3 layers were polycrystalline and acted as a protection layer for the inner GaP nanowires to permit their use at high temperature. The GaP/Ga2O3 structure may have potential applications in future nanodevice design. [ABSTRACT FROM AUTHOR]

Single crystals with formula of Be8(1-x)(B48)B2 (x∼0.6) were grown from high temperature Cu solution. Single crystal XRD measurements indicate that it is in tetragonal symmetry (space group of P42/nnm (No. 134)) and lattice constant of a=b=8.8557 Å and c=5.1157 Å, which is very similar with the compound BeB12 reported in 1960s’. However, we found the Be position in the crystal is quite different from the “old” compound BeB12. The structure was also confirmed with high resolution transmission electron microscopy (HRTEM) observations and its composition was obtained from electron energy loss spectrum (EELS) measurements. [Copyright &y& Elsevier]

Green emission has been obtained from c-axis oriented aluminum nitride (AlN) nanorods doped with terbium (Tb) on silicon (111). The nanorods were prepared by reactive radio-frequency magnetron sputtering in argon and nitrogen atmosphere using a target of Al and TbN mixtures, and characterized by x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The sharp characteristic emission lines observed in the photoluminescence and cathodoluminescence (CL) spectra at room temperature correspond to the Tb[sup 3+] intra-4f[sup n] shell transitions. The monochromatic (wavelength=554 nm) CL images with the high spatial resolution directly show the green emission from the well-aligned nanorods. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]