The analysis of multi-dimensional biomedical systems requires analysis techniques, which are able to deal with multivariate
data consisting of both time series as well as point processes. Univariate and bivariate analysis techniques in the frequency
domain for time series and point processes are established and investigated, although the number of investigations is strongly
biased towards time series. Actual multivariate techniques for time series or hybrids of time series and point processes are
scarcely addressed. Here, we present spectral analysis techniques which are able to analyse point processes as well as time
series. Thereby, univariate, bivariate as well as multivariate techniques are discussed. Applications to simulated as well
as real-world data reveal the abilities of the proposed techniques. 相似文献
We report the preparation of chiral oxygen atom-appended porphyrazines (pzs) as biomedical optical agents that absorb and emit in the near-IR wavelength range. These pzs take the form M[pz(A4-nBn)], where “A” and “B” represent moieties appended to the pz’s pyrrole entities, A = (2R,3R) 2,3-dimethyl-2,3-dimethoxy-1,4-diox-2-ene, B = β,β′-di-isopropoxybenzo, M is the incorporated metal ion (M = H2, Zn), and n =0, 1, 2 (-cis/-trans) and 3 ( Scheme 1 ). When dissolved in polar media, H2[pz(trans-A2B2)] 5a does not fluoresce and has a negligible quantum yield for singlet oxygen generation (ФΔ = 0.074 ± 0.001, methanol), as measured by the photo-oxidation of DMA. However, when sequestered in the nonpolar environment of a liposome, it displays strong NIR emission (λ max = 705 nm, Ф f = 0.087) and an extremely high singlet oxygen quantum yield (ФΔ→1). Of this series, H2[pz(trans-A2B2)] 5a is attractive as a potential optical probe, showing strongly fluorescent uptake by cells in culture, while 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide measurements of cell viability show no evidence of dark toxicity. This agent does show significant photoinduced toxicity suggesting that pzs such as 5a have promise as “theranostic” optical agents that can be visualized with fluorescence imaging while acting as a sensitizer for photodynamic therapy. Figure Scheme 1. Open in figure viewer PowerPoint Synthesis of Porphyrazines 3a – 7a , 3b – 7b . 相似文献