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The effects of electron beam irradiation on the electrical and the optical properties of zinc oxide (ZnO) and aluminum-doped zinc oxide (ZnO:Al) thin films, prepared by the sol-gel technique, were investigated. The grain size, surface morphology, sheet resistance, optical constants, absorption edge, and direct and indirect optical band gaps of these films were analyzed before and after exposure to electron beam. The decrease in the structural homogeneity and the crystallinity of the films after exposure to electron irradiation is observed. The irradiation causes increase in the sheet resistance and blueshift in the absorption edge for both ZnO and ZnO:Al films. The change in carrier concentration due to doping as well as the exposure to electron beam are responsible for the modified electrical and optical properties. [ABSTRACT FROM AUTHOR]

Purpose: Improving health-related quality of life (HRQL) is the main goal of palliative care and an important outcome for oncology trials. This study examines medical and sociodemographic determinants of HRQL in outpatients with advanced cancer.Methods: Patients with metastatic gastrointestinal, genitourinary, breast, lung or gynecological cancer, ECOG 0-2, and clinical prognosis of 6 months to 2 years were recruited from outpatient medical oncology clinics. HRQL was measured using the FACT-G questionnaire and the FACIT-Sp meaning and peace (existential) subscale. The influence of demographic and medical characteristics on HRQL was determined using t tests and analysis of variance, with Tukey's correction for multiple comparisons. Multivariate linear regression was used to determine independent predictors.Results: Of 285 patients, 57% were female and the median age was 61 years; 44% were alive at latest follow-up; and of those deceased, the mean survival time was 10 months. The strongest determinants of overall HRQL were increased age (p < 0.001), good performance status (PS; p < 0.001) and survival time >6 months (p = 0.001). Compared to patients receiving cancer treatment, those awaiting new treatment had worse emotional well-being (p < 0.001), while those on surveillance or whose treatment had been stopped had worse existential well-being (p = 0.03). Male gender predicted better emotional and physical well-being and lower income predicted worse social well-being.Conclusions: Age, PS, survival time, and treatment status are important determinants of HRQL in patients with advanced cancer. Decision aids, open communication, and involvement of supportive care specialists may improve emotional and existential distress associated with changing or stopping cancer treatment. [ABSTRACT FROM AUTHOR]

Two conformations of the retinal molecule have been studied in order to characterize the molecule's THz transmission spectra in both the ground and metastable states. When subjected to an adequate external excitation the retinal molecule can experience a change in conformation and associated THz transmission spectra. In an attempt to accomplish this characterization, the FTIR system was modified to include a simple off axis excitation source inside of the systems sample chamber. Measurements were made of the retinal molecule's THz spectra both with and without external excitation of the molecule. The results gathered were then compared with the results obtained from simulation. Data obtained from two retinal isomers reveal more spectral features at frequencies ~11 - 15 cm-1 than were predicted for these conformations. The most likely explanation for this is that the material is actually a mixture of several metastable conformations. There is correlation between simulated and measured THz spectra in the ground state at a frequency of 14 cm-1 for all-trans retinal. The strongest vibrational mode frequency predicted for the 9-cis conformation through modeling was 22 cm-1, which correlates quite well with the experimental line at 21.3 cm-1 in the ground state. When the 9-cis samples were exposed to UV illumination there was a noticeable change in the absorption spectra and this line at 21.3 cm-1 almost disappeared which can be related to the transformation of a 9-cis into a more stable all-trans retinal. The absorption spectra of all-trans retinal that is the most stable conformation showed very weak features in experimental spectra, with some of them changing under illumination. [ABSTRACT FROM PUBLISHER]

In this paper, we show that periodic arrays of rectangular slots with subwavelength width provide for local electromagnetic field enhancements due to edge effects in low-frequency range, 10-25 cm-1. Periodic structures of Au, doped Si, and InSb with subwavelength thickness were studied. The half power enhancement width is ~500 nm and less around the slot edges in all cases, thereby possibly bringing terahertz (THz) sensing to the nanoscale. InSb is confirmed to offer the best results with the local power enhancements on the order of 1100 at frequency 14 cm-1. InSb and Si have large skin depths in the frequency range of interest and so the analysis of their structures was done through the Fourier expansion method of field diffracted from gratings. Au, however, has small skin depths at these frequencies compared with the thickness. Surface impedance boundary conditions were employed to model the Au structure, for which the Fourier expansion method was unsuitable owing to the huge magnitude of Au permittivity at these frequencies. The applications possibly include development of novel biosensors, with the strongly enhanced local electromagnetic fields leading to increased detection sensitivity, and monitoring biophysical processes such as DNA denaturation. [ABSTRACT FROM PUBLISHER]