Off-iso Winston-Lutz test on seven linear accelerators.

Purpose: The aim of this study is to find optimal gantry, collimator, and couch angles for performing single isocenter, multiple target stereotactic radiosurgery (SIMT-SRS). Nineteen angle sets were tested across seven linear accelerators for radiation-isocenter coincidence and off-isocenter coincidence. The off-isocenter Winston-Lutz test was performed to evaluate the accuracy of isocenter alignment for each angle set, and optimal angle sets as well as maximum off-isocenter distance to target for each angle set was determined.

Thermoresponsive Amphiphilic Block Copolymer-Stablilized Gold Nanoparticles: Synthesis and High Catalytic Properties.

A series of novel well-defined 8-hydroxyquinoline (HQ)-containing thermoresponsive amphiphilic diblock copolymers {poly(styrene- co-5-(2-methacryloylethyloxy-methyl)-8-quinolinol)- b-poly( N-isopropylacrylamide) P(St- co-MQ)- b-PNIPAm (P1,2), P(NIPAm- co-MQ)- b-PSt (P3,4)} and triblock copolymer poly( N-isopropylacrylamide)- b-poly(methyl-methacrylate- co-5-(2-methacryloylethyloxymethyl)-8-quinolinol)- b-polystyrene PNIPAm- b-P(MMA- co-MQ)- b-PSt (P5) were prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization, and their self-assembly behaviors were studied. Block copolymer P1-P5-stabilized gold nanoparticles (Au@P1-Au@P5) with a small size and a narrow distribution were obtained through the in situ reduction of gold precursors in an aqueous solution of polymer micelles with HQ as the coordination groups. The resulting Au@P nanohybrids possessed excellent catalytic activity for the reduction of nitrophenols using NaBH.

The clinical application of in-house double lower limb auxiliary device in treating pelvic tumors.

Objective: Patient positioning accuracy is critical in radiotherapy. To improve the patient positioning accuracy, a double lower limb auxiliary device has been developed to fix pelvis patients to treatment couch. A clinical study for comparing new device to conventional devices has been performed.

Measurements of lateral penumbra for uniform scanning proton beams under various beam delivery conditions and comparison to the XiO treatment planning system.

Purpose: The main purposes of this study were to (1) investigate the dependency of lateral penumbra (80%-20% distance) of uniform scanning proton beams on various factors such as air gap, proton range, modulation width, compensator thickness, and depth, and (2) compare the lateral penumbra calculated by a treatment planning system (TPS) with measurements.

Methods: First, lateral penumbra was measured using solid-water phantom and radiographic films for (a) air gap, ranged from 0 to 35 cm, (b) proton range, ranged from 8 to 30 cm, (c) modulation, ranged from 2 to 10 cm, (d) compensator thickness, ranged from 0 to 20 cm, and (e) depth, ranged from 7 to 15 cm. Second, dose calculations were computed in a virtual water phantom using the XiO TPS with pencil beam algorithm for identical beam conditions and geometrical configurations that were used for the measurements.

Misdiagnosis of left supraclavicular lymph node metastasis of hepatocellular carcinoma: a case report.

Left supraclavicular lymph node metastasis is a rare presentation of hepatocellular carcinoma (HCC). This phenomenon is easily neglected in the clinic. A 56-year-old man presented with HCC.

Quantifying tumor-selective radiation dose enhancements using gold nanoparticles: a monte carlo simulation study.

Gold nanoparticles can enhance the biological effective dose of radiation delivered to tumors, but few data exist to quantify this effect. The purpose of this project was to build a Monte Carlo simulation model to study the degree of dose enhancement achievable with gold nanoparticles. A Monte Carlo simulation model was first built using Geant4 code.

Expression pattern of connexins in the corneal and limbal epithelium of a primate.

Purpose: To detect the expression pattern of connexins in epithelial cells of the central cornea and limbus of the macaque.

Methods: Total RNA was extracted from the central corneal and limbal epithelia of Macaca fascicularis and processed by reverse transcriptase-polymerase chain reaction with isoform primers to detect the expression of 16 connexin (Cx). Immunofluorescent staining of frozen sections of corneal tissue confirmed and localized connexin proteins expression.

Numerical and structural variations of the X chromosomes and no. 2 autosomes in mandarin vole, Microtus mandarinus (Rodentia).

Here we describe our studies on Microtus mandarinus faeceus of Jiangyan in Jiangsu province of China. By karyotype and G-banding analysis we have found variation in chromosome number and polymorphisms of the X chromosome and the second pair of autosomes of the subspecies. Chromosome number of the subspecies is 2n=47-50.

Young-type interference in (e, 2e) ionization of H(2).

We have investigated the electron impact single ionization of the hydrogen molecule, with fully determined kinematics. The experimental and theoretical results are compared with He ionization under the same conditions. The results indicate that the ejected electron angular distribution for H(2) is modified due to Young-type interference between ionization amplitudes for scattering from the two centers in the hydrogen molecule.

Experimental and theoretical (e,2e) ionization cross sections for a hydrogen target at 75.3 eV incident energy in a coplanar asymmetric geometry.

Very recently it was shown that the molecular three-body distorted wave (M3DW) approach gives good agreement with the shape of the experimental data for electron-impact ionization of H(2) in a coplanar symmetric geometry, providing the incident electrons have an energy of 35 eV or greater. One of the weaknesses of these studies was that only the shape of the cross section could be compared to experiment, since there was no absolute or relative normalization of the data. Here we report a joint experimental/theoretical study of electron-impact ionization of H(2) in a coplanar asymmetric geometry where the energy of the incident electron was fixed, and different pairs of final state electron energies were used.

Distorted wave Born and three-body distorted wave Born approximation calculations of the fully differential cross section for electron-impact ionization of nitrogen molecules.

Currently there are no reliable theoretical approaches for calculating fully differential cross sections (FDCSs) for low-energy electron-impact ionization of large molecules. We have recently proposed the orientation-averaged molecular orbital (OAMO) for calculating cross sections averaged over molecular orientations. In this paper, we use the OAMO to calculate distorted wave Born approximation (DWBA) and molecular three-body distorted wave (M3DW) Born approximation FDCS for electron-impact ionization of the nitrogen molecule.

An elementary method for calculating orientation-averaged fully differential electron-impact ionization cross sections for molecules.

Currently there are no reliable theoretical approaches for calculating fully differential cross sections (FDCS) for low-energy electron-impact ionization of large molecules. We have recently introduced the distorted-wave impulse approximation as a first step in developing improved theoretical approaches. One significant obstacle to evaluating improved theoretical approaches which require significant computer resources lies in the fact that the existing experimental data require taking averages over all molecular orientations.

[A family history of vitiligo with autosomal dominant inheritance].

A family history of vitiligo was reported in this paper,and the reason causing disease was discussed. We think that the vitiligo in the family history is caused by autosomal dominant inheritance.

[Detection of Y chromosome in human and Microtus mandarinus with FISH].

The purpose of the investigation was to detect the Y chromosome of human and Microtus mandarinus with the satellite DNA probe in human's Yq by fluorescence in situ hybridization(FISH). We hybridizied the probe with the metaphase chromosome and interphase nucleus specimens of humanbeing and Microtus mandarinus respectively. The results showed that there was hybridization signal on metaphase chromosome and interphase nucleus of human, but no signal on metaphase chromosome and interphase nucleus of Microtus mandarinus.

The origin of the genetical diversity of Microtus mandarinus chromosomes.

Here we describe our comparative studies on two types of X chromosomes, namely X(M) and X(SM,) of the mandarin vole (Microtus mandarinus). By chromosome G- and C-banding analysis, we have found that two different types of X chromosomes exist in mandarin voles. The two types of X chromosomes present two different G- and C-banding patterns: the X(M) chromosome is a longer metacentric X chromosome which is C-band negative; and the X(SM) is a shorter submetacentric X chromosome which has one C-band at the centromere and another one at the middle part of the short arm.