Synthesis,photophysical and photochemical properties of tetra- and octa-substituted gallium and indium phthalocyanines

The synthesis, photophysical and photochemical properties of the tetra- and octa-[4-(benzyloxyphenoxy)] substituted gallium(III) and indium(III) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, ¹H NMR spectroscopy and electronic spectroscopy. General trends are described for quantum yields of photodegredation, fluorescence quantum yields and lifetimes, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds in dimethylsulfoxide (DMSO). Substituted indium phthalocyanine complexes (7b–9b) showed much higher quantum yields of triplet state and shorter triplet lifetimes, compared to the substituted GaPc derivatives due to enhanced intersystem crossing (ISC) in the former. The gallium and indium phthalocyanine complexes showed phototransformation during laser irradiation due to ring reduction. The singlet oxygen quantum yields (Φ_Δ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.51 to 0.94. Thus, these complexes show potential as photodynamic therapy of cancer.     

Synthesis and solvent effects on the electronic absorption and fluorescence spectral properties of substituted zinc phthalocyanines

The synthesis and spectroscopic properties of the following tetra- and octa-substituted aryloxy zinc(II) phthalocyanines are reported for the first time: 1,(4)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (7); 2,(3)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (8); 2,3-(octabenzyloxyphenoxyphthalocyaninato) zinc(II) (9). The new compounds have been characterized by elemental analysis, IR, ¹H NMR spectroscopy and electronic spectroscopy. Spectroscopic properties of these compounds were investigated in different solvents. Protonation of non-peripherally substituted complex 7 resulted in the splitting and red-shifting of the Q-band. The peripherally substituted derivatives 8 and 9, did not show the split in the Q-band. Fluorescence spectra of the derivatives show Stokes shifts typical of MPc complexes.     

Optimal Timing to Initiate Medical Treatment for a Disease Evolving as a Semi-Markov Process

In this paper, we consider the problem of the optimal timing to initiate a medical treatment. In the absence of treatment, we model the disease evolution as a semi-Markov process. The optimal time to initiate the treatment is a stopping time, which maximizes the total expected reward for the patient. We propose a stochastic dynamic programming formulation to find this stopping time. Under some plausible conditions, we show that the maximum total expected reward at the start of a health state will be smaller when the patient is in a more severe state. We then prove that the optimal policy for initializing the treatment is determined by a time threshold for each given health state. That is, in each health state, the treatment should be planned to start, when the patient’s duration time in the health state reaches (or exceeds, in the case of a late observation of the patient’s health status) a certain threshold level. We also present numerical examples to illustrate our model and to provide managerial insights.     

Synthesis, photophysical and photochemical properties of poly(oxyethylene)-substituted zinc phthalocyanines

The synthesis, photophysical and photochemical properties of the tetra- and octa-poly(oxyethylene)substituted zinc (II) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. General trends are described for photodegradation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethylsulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The effects of the substituents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (3a, 5a and 6a) are also reported. The singlet oxygen quantum yields (Phi(Delta)), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.60 to 0.72. Thus, these complexes show potential as Type II photosensitizers. The fluorescence of the complexes was quenched by benzoquinone (BQ).     

High-Throughput Proteomics Enabled by a Photocleavable Surfactant

Mass spectrometry (MS)-based proteomics provides unprecedented opportunities for understanding the structure and function of proteins in complex biological systems; however, protein solubility and sample preparation before MS remain a bottleneck preventing high-throughput proteomics. Herein, we report a high-throughput bottom-up proteomic method enabled by a newly developed MS-compatible photocleavable surfactant, 4-hexylphenylazosulfonate (Azo) that facilitates robust protein extraction, rapid enzymatic digestion (30 min compared to overnight), and subsequent MS-analysis following UV degradation. Moreover, we developed an Azo-aided bottom-up method for analysis of integral membrane proteins, which are key drug targets and are generally underrepresented in global proteomic studies. Furthermore, we demonstrated the ability of Azo to serve as an “all-in-one” MS-compatible surfactant for both top-down and bottom-up proteomics, with streamlined workflows for high-throughput proteomics amenable to clinical applications.     

Characteristics of traps in TlInS2 single crystals

Characteristics of charge traps in TlInS₂ single crystals are investigated by the use of thermally stimulated current (TSC) technique. The TSC spectra of the sample from 80 K to 300 K are recorded at a constant heating rate. The spectra reveal that there are several trapping levels associated with the complex structure of overlapping peaks. The experimental results indicate that the traps in TlInS₂ associated with the spectra in the measuring range of temperature obey the monomolecular (first order) kinetics. Thus, the spectra are resolved into first order shaped peaks by the use of computerized best fit procedure. The trapping parameters; such as the energy depth, temperature dependent frequency factor and capture cross section, together with concentrations of the corresponding six discrete levels are computed. These centers all having low capture cross sections with strong temperature dependence are found to be at the energies of 0.11 eV, 0.22 eV, 0.25 eV, 0.26 eV, 0.29 eV and 0.30 eV with high concentrations of 6.6 × 10¹⁶, 2.0 × 10¹⁷, 3.3 × 10¹⁷, 9.6 × 10¹⁶, 2.3 × 10¹⁷ and 4.0 × 10¹⁷ cm^?3, respectively.     

Ce0.8Sm0.2O1.9 synthesis for solid oxide fuel cell electrolyte by ultrasound assisted co-precipitation method

In this study, the synthesis of Ce_0.8Sm_0.2O_1.9 (SDC) solid electrolyte by the ultrasound assisted co-precipitation method was accomplished to explore the effects of ultrasound power, ultrasound pulse ratio and probe type upon the ionic conductivity of SDC as well as the lattice parameter, the microstructure and the density. Fine powders of uniform crystallite sizes (average 11.70 ± 0.62 nm) were obtained, needing lower sintering temperature. The SDC powders were successfully sintered to a relative density of over 95% at 1200 °C (5 °C min^?1) for 6 h. The micrograph of SDC pellets showed non-agglomerated and well-developed grains with average size of about 200 nm. X-ray diffraction analysis showed that the lattice parameter increased with increasing acoustic intensity and reached a maximum for the 14.94 W cm^?2. Further, a linear relationship was detected between the lattice parameter and the ionic conductivity, inspiring a dopant like effect of US on the electrolyte properties. The highest ionic conductivity as σ_800°C = 3.07 × 10^?2 S cm^?1 with an activation energy E_a = 0.871 kJ mol^?1 was obtained with pulsed ultrasound for an acoustic intensity of 14.94 W cm^?2, using 19 mm probe and 8:2 pulse ratio.     

Strongly almost (<Emphasis Type="Italic">ω, λ, q</Emphasis>)-summable sequences

The purpose of this paper is to introduce the spaces of sequences that are strongly almost (ω, λ, q)-summable with respect to a modulus function. We give some relations related to these sequence spaces. It is also shown that if a sequence is strongly (ω, λ, q)-summable with respect to a modulus function, then it is S(λ _q )-statistically convergent.     

One-Parameter Homothetic Motion in the Hyperbolic Plane and Euler-Savary Formula

In [10] one-parameter planar motion was first introduced and the relations between absolute, relative, sliding velocities (and accelerations) in the Euclidean plane \mathbb E²{{\mathbb E}^2} were obtained. Moreover, the relations between the complex velocities of one-parameter motion in the complex plane were provided by [10]. One-parameter planar homothetic motion was defined in the complex plane, [9]. In this paper, analogous to homothetic motion in the complex plane given by [9], one-parameter planar homothetic motion is defined in the hyperbolic plane. Some characteristic properties about the velocity vectors, the acceleration vectors and the pole curves are given. Moreover, in the case of homothetic scale h identically equal to 1, the results given in [15] are obtained as a special case. In addition, three hyperbolic planes, of which two are moving and the other one is fixed, are taken into consideration and a canonical relative system for one-parameter planar hyperbolic homothetic motion is defined. Euler-Savary formula, which gives the relationship between the curvatures of trajectory curves, is obtained with the help of this relative system.