Going from 3D/3D to 2D/3D registration for noncoplanar setup verification in intracranial single-isocenter multiple-target hypofractionated stereotactic radiotherapy: comparison between kilo-voltage/mega-voltage image pairs and noncoplanar cone-beam computed tomography.

Background: Single-isocenter (SI) noncoplanar volumetric modulated arc therapy (NC-VMAT) has been widely used in stereotactic radiosurgery (SRS) or hypofractionated stereotactic radiotherapy (HSRT) for multiple brain metastases (BMs). However, it is critical to verify patient positioning at a noncoplanar couch angle. This study aimed to compare the noncoplanar setup discrepancies between kilo-voltage/mega-voltage image (kV/MV) orthogonal image pairs with a 2-dimensional/3-dimensional (2D/3D) matching mode and noncoplanar cone-beam computed tomography (NC-CBCT) with a 3D/3D matching mode in SI NC-VMAT HSRT for multiple BMs.

Computational hyperspectral devices based on quasi-random metasurface supercells.

Computational hyperspectral devices that use artificial filters have shown promise as compact spectral devices. However, the current designs are restricted by limited types and geometric parameters of unit cells, resulting in a high cross-correlation between the transmission spectra. This limitation prevents the fulfillment of the requirement for compressed-sensing-based spectral reconstruction.

Effective method to reduce the normal brain dose in single-isocenter hypofractionated stereotactic radiotherapy for multiple brain metastases.

Background And Purpose: Island blocking and dose leakage problems will lead to unnecessary irradiation to normal brain tissue (NBT) in hypofractionated stereotactic radiotherapy (HSRT) for multiple brain metastases (BM) with single-isocenter volumetric modulated arc therapy (VMAT). The present study aimed at investigating whether reducing the number of metastases irradiated by each arc beam could minimize these two problems.

Materials And Methods: A total of 32 non-small-cell lung cancer (NSCLC) patients with multiple BM received HSRT (24-36 Gy/3 fractions) with single-isocenter VMAT, where each arc beam only irradiated partial metastases (pm-VMAT), were enrolled in this retrospective study.

Abnormal Rheological Phenomena in Newtonian Fluids in Electroosmotic Flows in a Nanocapillary.

Abnormal rheological phenomena arising in Tris-borate-ethylenediaminetetraacetic acid solutions (believed to be Newtonian fluids) were observed in direct current electroosmotic flows within a nanocapillary with a diameter of 200 nm under a low electric field of tens of volts per meter. In solutions with different concentrations and pH values, the flow behavior indices of the power-law fluids were calculated on the basis of current-voltage relations. When the electric field intensity was below a critical value of 6.

High-throughput imaging of zebrafish embryos using a linear-CCD-based flow imaging system.

High-throughput imaging and screening is essential for biomedical research and drug discovery using miniature model organisms such as zebrafish. This study introduces a high-speed imaging system which illuminates zebrafish embryos flowing through a capillary tube with a sheet of light and captures them using a linear charge-coupled device (CCD). This system can image dozens of zebrafish embryos per second.

Plasmonic hotspots of dynamically assembled nanoparticles in nanocapillaries: Towards a micro ribonucleic acid profiling platform.

Plasmonic hot spots, generated by controlled 20-nm Au nanoparticle (NP) assembly, are shown to suppress fluorescent quenching effects of metal NPs, such that hair-pin FRET (Fluorescence resonance energy transfer) probes can achieve label-free ultra-sensitive quantification. The micron-sized assembly is a result of intense induced NP dipoles by focused electric fields through conic nanocapillaries. The efficient NP aggregate antenna and the voltage-tunable NP spacing for optimizing hot spot intensity endow ultra-sensitivity and large dynamic range (fM to pM).

Self-retracting motion of graphite microflakes.

We report the observation of a novel phenomenon, the self-retracting motion of graphite, in which tiny flakes of graphite, after being displaced to various suspended positions from islands of highly orientated pyrolytic graphite, retract back onto the islands under no external influences. Reports of this phenomenon have not been found in the literature for single crystals of any kind. Models that include the van der Waals force, electrostatic force, and shear strengths were considered to explain the observed phenomenon.