Nonfunctionalized nanocrystals can exploit a cell's active transport machinery delivering them to specific nuclear and cytoplasmic compartments

We use high content cell analysis, live cell fluorescent imaging, and transmission electron microscopy approaches combined with inhibitors of cellular transport and nuclear import to conduct a systematic study of the mechanism of interaction of nonfunctionalized quantum dots (QDs) with live human blood monocyte-derived primary macrophages and cell lines of phagocytic, epithelial, and endothelial nature. Live human macrophages are shown to be able to rapidly uptake and accumulate QDs in distinct cellular compartment specifically to QDs size and charge. We show that the smallest QDs specifically target histones in cell nuclei and nucleoli by a multistep process involving endocytosis, active cytoplasmic transport, and entering the nucleus via nuclear pore complexes. Treatment of the cells with an anti-microtubule agent nocodazole precludes QDs cytoplasmic transport whereas a nuclear import inhibitor thapsigargin blocks QD import into the nucleus. These results demonstrate that the nonfunctionalized QDs exploit the cell's active transport machineries for delivery to specific intranuclear destinations.     

Eigen electromagnetic oscillations in the waveguide-dielectric resonator with two-layer filling

The method of the solution problem on the eigen oscillations spectrum of electromagnetic field in the waveguide-dielectric resonator with the two-layer dielectric element was presented. The numerical calculations of the resonance frequencies for theHE ₁₁₁-,E ₀₁₁- andH ₀₁₁-oscillations types in the investigated structure were performed. The calculation results were correlated with experimental data.     

Gold nanorods with a hematoporphyrin-loaded silica shell for dual-modality photodynamic and photothermal treatment of tumors in vivo

Nanocomposites （NCs） consisting of a gold nanorod core and a mesoporous silica shell doped with hematoporphyrin （HP） have been fabricated in order to improve the efficiency of cancer treatment by combining photothermal and photodynamic therapies （PDT ＋ PTT） in vivo. In addition to the long-wavelength plasmon resonance near 810-830 nm, the fabricated NCs exhibited a 400-nm absorbance peak corresponding to bound HP, generated singlet oxygen under 633-nm excitation near the 632.5-nm Q-band, and produced heat under a 808-nm near-infrared （NIR） laser irradiation. These modalities were used for a combined PDT ＋ PTT treatment of large （about 3 cm3） solid tumors in vivo with a xenorafted tumor rat model. NCs were directly injected into tumors and irradiated simultaneously with 633-nm and 808-nm lasers to stimulate the combined photodynamic and photothermal activities of NCs. The efficiency of the combined therapy was evaluated by optical coherence tomography, histological analysis, and by measurements of the tumor volume growth during a 21-day period. The NC-mediated PDT led to weak changes in tissue histology and to a moderate 20% decrease in the tumor volume. In contrast, the combined PDT ＋ PTT treatment resulted in the large-area tumor necrosis and led to dramatic decrease in the tumor volume.     

Angular diagram of broadband emission of millimeter-sized water droplets exposed to gigawatt femtosecond laser pulses

We report on the experiments on the interaction of gigawatt femtosecond laser pulses with suspended millimeter-sized water droplets. The transparent droplets experienced laser-induced breakdown and explosive boiling up and emitted a broadband radiation. This radiation covers the spectral range from 450 to 1100?nm and consists of the spectrum of laser pulse scattered and transformed by the droplet due to self-phase modulation and plasma emission produced in water during photoionization. The droplet emission spectrum showed remarkable broadening at all viewing angles and is maximal in the direction of the laser exit from the droplet. The enlargement of the droplet results in additional spectral spreading of the emitted radiation. The depth and amount of laser pulse spectral self-transformations upon propagation through the water droplet are simulated by means of numerical calculations.     

Numerical investigation of deformation localization and crack formation in elastic brittle-plastic materials

Localized deformation band formation and crack generation in elastic brittle-plastic materials were simulated numerically in various loading conditions. Cracking patterns for a specimen with a failed inclusion and for a damaged layer of a geomedium in shear, as well as for a sandstone specimen in compression, were obtained. To describe deformation, a complex approach was used. According to this approach, in the course of plastic deformation damages are accumulated and govern bulk plastic deformation. Due to damage accumulation, strength decreases and material degradation occurs, while macrocrack opening and material fracture take place only under the action of tensile stresses.     

One-Parameter Model for the Estimation of IC Susceptibility to Proton-Induced Single-Event Upsets

Singe-event upsets (SEUs) caused by high-energy protons are considered. An analytical model is proposed to represent the dependence of SEU cross section on proton energy. The model is based on a simple mechanism of proton-induced nuclear reactions in silicon. A computer simulation is conducted by the model. The results are found to agree with previous experiments. They indicate that the model enables one to predict susceptibility to proton-induced SEUs on the basis of a single value of SEU cross section measured at a proton energy higher than 100 MeV. It is shown that the approach may also work for heavy ions.     

Prediction of Local and Global Ionization Effects on ICs: The Synergy between Numerical and Physical Simulation

A review is presented of an integrated approach to hardness assurance, embracing single-event and global pulsed-ionization effects. The strategy essentially combines numerical and physical simulation in order to obtain reliable data on IC radiation response with minimum expenditure of time and money. The way in which calculations and measurements should be combined depends on the type of IC and the radiation conditions. It is shown that the cost of measurement can be reduced by using laboratory radiation simulators and each form of radiation of interest can be simulated with an agent readily available for the tester. Particular coverage is given to simulation with lasers.     

The architectonics of the lymphatic networks in the sheep heart

Lymphatic networks of the heart were studied in sheep. Principal scheme of lymphatic networks structural organization in endocardium, myocardium and epicardium of the mammals studied was established to have a series of regularities similar to those in man and animals although possessing specific peculiarities. Lymphomicrocirculatory bed of the heart is composed of interdependent lymphatic networks of endocardium, myocardium and epicardium. Endocardial and epicardial lymphatic networks are plane and single-layered, while myocardial one is spatial. All heart coats lymphatic networks are characterized with local peculiarities (different loop parameters, capillary diameter and density in some areas) which indicates varying drainage and state of metabolism in different heart region.