Read by QxMD icon Read

V beam

Alexey P Porfirev, Andrey V Ustinov, Svetlana N Khonina
Currently, cylindrical beams with radial or azimuthal polarization are being used successfully for the optical manipulation of micro- and nano-particles as well as in microscopy, lithography, nonlinear optics, materials processing, and telecommunication applications. The creation of these laser beams is carried out using segmented polarizing plates, subwavelength gratings, interference, or light modulators. Here, we demonstrate the conversion of cylindrically polarized laser beams from a radial to an azimuthal polarization, or vice versa, by introducing a higher-order vortex phase singularity...
December 5, 2016: Scientific Reports
Fang Lian, Fan Zhang, Lin Yang, Leilei Ma, Yadi Li
A heterostructural LiNi0.35Mn1.65O4-δ-LiNi0.5Mn1.5O4 was achieved via constructing the concentration-gradient material with an average composition of LiNi0.4Mn1.6O4-δ. The as-obtained samples have been characterized by the cross sectional scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS) that the core material LiNi0.35Mn1.65O4-δ is encapsulated completely by a concentration-gradient shell with the outmost layer of LiNi0.5Mn1.5O4. Demonstrated by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) analysis with low-energy Ar neutral beam etching method, the structurally stable P4332 phase on the surface coordinates the high conductive Fd-3m phase in the bulk without any detectable interface...
April 25, 2017: ACS Applied Materials & Interfaces
Nikhil V Jain, Affaf A Gharatkar, Bandish A Parekh, Smita I Musani, Umang Deepak Shah
AIM: Placement of implants in the maxillary anterior region needs to be preceded by careful analysis of the area as in addition to the functional aspect the esthetic outcome is of prime importance. This descriptive study evaluated anatomical characteristics and dimensions of the nasopalatine canal (NC) from coronal, sagittal and axial aspects using cone beam computed tomography (CBCT) giving it a three dimensional analytical approach. Also the dimensions of the corresponding buccal bone plate (BBP) of the alveolar process were evaluated...
June 2017: Journal of Maxillofacial and Oral Surgery
G Q V Oliveira, M A Rossi, T V Vasconcelos, F S Neves, I Crusoé-Rebello
The aim of this study was to evaluate the anatomical linear measurements of the descending palatine canal and the pterygomaxillary fissure for Le Fort I preoperative planning. Seventy-five patients, comprising 46 females (61.3%) and 29 males (39.7%), underwent multi-slice computed tomography examinations performed for preoperative orthognathic surgical planning. The images were categorized according to sex, craniofacial side, and skeletal and craniofacial patterns. The anterior length between the descending palatine canal and the lateral wall of the piriform rim showed a higher mean value for males compared to females (P=0...
April 21, 2017: International Journal of Oral and Maxillofacial Surgery
Angelia Tran, Kaley Woods, Dan Nguyen, Victoria Y Yu, Tianye Niu, Minsong Cao, Percy Lee, Ke Sheng
BACKGROUND: It is useful to predict planned dosimetry and determine the eligibility of a liver cancer patient for SBRT treatment using knowledge based planning (KBP). We compare the predictive accuracy using the overlap volume histogram (OVH) and statistical voxel dose learning (SVDL) KBP prediction models for coplanar VMAT to non-coplanar 4π radiotherapy plans. METHODS: In this study, 21 liver SBRT cases were selected, which were initially treated using coplanar VMAT plans...
April 24, 2017: Radiation Oncology
Chiu-Yen Wang, Yu-Chen Hong, Zong-Jie Ko, Ya-Wen Su, Jin-Hua Huang
In this study, defect-free zinc blende GaAs nanowires on Si (111) by molecular beam epitaxy (MBE) growth are systematically studied through Au-assisted vapor-liquid-solid (VLS) method. The morphology, density, and crystal structure of GaAs nanowires were investigated as a function of substrate temperature, growth time, and As/Ga flux ratio during MBE growth, as well as the thickness, annealing time, and annealing temperature of Au film using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), cathodoluminescence (CL), and Raman spectroscopy...
December 2017: Nanoscale Research Letters
V A Schanz, F Wagner, M Roth, V Bagnoud
We report on a novel technique to reduce the noise level in scanning third order cross-correlation. Large angles between the interacting beams combined with adapted crystal parameters lead to a significant decrease of noise photon generation while maintaining efficient generation of the third order signal. An enhanced scanning cross-correlator was developed based on the new technique proposed. In tests at the PHELIX laser facility this novel correlator performed within a dynamic range of 12.5 orders of magnitude...
April 17, 2017: Optics Express
Jasmine A Oliver, Omar A Zeidan, Sanford L Meeks, Amish P Shah, Jason Pukala, Patrick Kelly, Naren R Ramakrishna, Twyla R Willoughby
PURPOSE: The purpose of this study was to characterize the Mobius AIRO Mobile CT System for localization and image-guided proton therapy. This is the first known application of the AIRO for proton therapy. METHODS: Five CT images of a Catphan(®) 504 phantom were acquired on the AIRO Mobile CT System, Varian EDGE radiosurgery system cone beam CT (CBCT), Philips Brilliance Big Bore 16 slice CT simulator, and Siemens SOMATOM Definition AS 20 slice CT simulator. DoseLAB software v...
April 24, 2017: Journal of Applied Clinical Medical Physics
Tae Wan Kim, Euncheol Choi, Jeonghoon Park, Dong-Ho Shin, Su Kyung Jung, Susie Seok, Kwan Ho Cho, Joo-Young Kim, Dae Yong Kim, Tae Hyun Kim, Yang Kwon Suh, Yeon Joo Kim, Sung Ho Moon
Purpose: This study retrospectively evaluated the clinical outcomes and complications of proton beam therapy (PBT) in a single institution in Korea and quantitatively analyzed the change in tumor volume after PBT using magnetic resonance imaging (MRI). Materials and Methods: Twenty-four treatment-naïve patients who underwent PBT for choroidal melanoma between 2009 and 2015 were reviewed. Dose fractionation was 60-70 CGE over 5 fractions. Orbital MRIs were taken at baseline and 3, 6, and 12 months after PBT and annually thereafter...
April 19, 2017: Cancer Research and Treatment: Official Journal of Korean Cancer Association
Yunsong Yan, Tommaso Santaniello, Luca Giacomo Bettini, Chloé Minnai, Andrea Bellacicca, Riccardo Porotti, Ilaria Denti, Gabriele Faraone, Marco Merlini, Cristina Lenardi, Paolo Milani
Electroactive ionic gel/metal nanocomposites are produced by implanting supersonically accelerated neutral gold nanoparticles into a novel chemically crosslinked ion conductive soft polymer. The ionic gel consists of chemically crosslinked poly(acrylic acid) and polyacrylonitrile networks, blended with halloysite nanoclays and imidazolium-based ionic liquid. The material exhibits mechanical properties similar to that of elastomers (Young's modulus ≈ 0.35 MPa) together with high ionic conductivity. The fabrication of thin (≈100 nm thick) nanostructured compliant electrodes by means of supersonic cluster beam implantation (SCBI) does not significantly alter the mechanical properties of the soft polymer and provides controlled electrical properties and large surface area for ions storage...
April 18, 2017: Advanced Materials
Felix Tabbert, Christian Schelte, Mustapha Tlidi, Svetlana V Gurevich
We report on the dynamics of localized structures in an inhomogeneous Swift-Hohenberg model describing pattern formation in the transverse plane of an optical cavity. This real order parameter equation is valid close to the second-order critical point associated with bistability. The optical cavity is illuminated by an inhomogeneous spatial Gaussian pumping beam and subjected to time-delayed feedback. The Gaussian injection beam breaks the translational symmetry of the system by exerting an attracting force on the localized structure...
March 2017: Physical Review. E
Vladimir V Kesaev, Alexei D Kiselev, Evgeny P Pozhidaev
We study the electro-optic properties of subwavelength-pitch deformed-helix ferroelectric liquid crystals (DHFLC) illuminated with unpolarized light. In the experimental setup based on the Mach-Zehnder interferometer, it was observed that the reference and the sample beams being both unpolarized produce the interference pattern which is insensitive to rotation of in-plane optical axes of the DHFLC cell. We find that the field-induced shift of the interference fringes can be described in terms of the electrically dependent Pancharatnam relative phase determined by the averaged phase shift, whereas the visibility of the fringes is solely dictated by the phase retardation...
March 2017: Physical Review. E
Alexey P Porfirev, Mikhail S Kirilenko, Svetlana N Khonina, Roman V Skidanov, Victor A Soifer
A theoretical and experimental study of the propagation of vortex laser beams in a random aerosol medium is presented. The theoretical study is based on the extended Huygens-Fresnel principle with the generation of a random field, using the fast Fourier transform. The simulation shows that the stability of vortex beams to fluctuations of an optical medium falls with rising order of optical vortices. Moreover, a coherence length (radius) of the random medium is of great importance. The coherence radius extension affects adversely the conservation of a beam structure in the random medium...
April 10, 2017: Applied Optics
R C Shah, B M Haines, F J Wysocki, J F Benage, J A Fooks, V Glebov, P Hakel, M Hoppe, I V Igumenshchev, G Kagan, R C Mancini, F J Marshall, D T Michel, T J Murphy, M E Schoff, K Silverstein, C Stoeckl, B Yaakobi
We present narrow-band self-emission x-ray images from a titanium tracer layer placed at the fuel-shell interface in 60-laser-beam implosion experiments at the OMEGA facility. The images are acquired during deceleration with inferred convergences of ∼9-14. Novel here is that a systematically observed asymmetry of the emission is linked, using full sphere 3D implosion modeling, to performance-limiting low mode asymmetry of the drive.
March 31, 2017: Physical Review Letters
Kazuhide Nishihara, Shin-Ichiro Yoshimine, Takahiro Goto, Kiyohide Ishihata, Ken-Ichi Kume, Takuya Yoshimura, Norifumi Nakamura, Akira Arasaki
OBJECTIVE: The purpose of the present study was to elucidate the anatomic characteristics of the maxillary premolars for the planning of dental treatment using cone beam computed tomography (CBCT). STUDY DESIGN: CBCT images were obtained for 150 maxillary premolars in 68 patients. The internal angle formed by the long axis of the maxillary premolars and the long axis of the alveolar bone was evaluated on the cross-sectional images. The vertical relationships between the maxillary premolars and the maxillary sinus were classified into 5 categories...
May 2017: Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Lingli Zhang, Ling Wang, Uma S Hiremath, Hari Krishna Bisoyi, Geetha G Nair, Channabasaveshwar V Yelamaggad, Augustine M Urbas, Timothy J Bunning, Quan Li
Controllable manipulation of self-organized dynamic superstructures of functional molecular materials by external stimuli is an enabling enterprise. Herein, we have developed a thermally driven, self-organized helical superstructure, i.e., thermoresponsive cholesteric liquid crystal (CLC), by integrating a judiciously chosen thermoresponsive chiral molecular switch into an achiral liquid crystalline medium. The CLC in lying state, in both planar and twisted nematic cells, exhibits reversible in-plane orthogonal switching of its helical axis in response to the combined effect of temperature and electric field...
April 12, 2017: Advanced Materials
S N Mantsevich, V Ya Molchanov, K B Yushkov, V S Khorkin, M I Kupreychik
Ultrasound wave reflection from one of the crystal faces is the convenient way to arouse the acoustic beam with a desired propagation direction in acousto-optic cells with collinear and quasi-collinear interaction geometries. The reflection process effects on the ultrasound field amplitude and phase structure. The method to simulate the reflected finite ultrasound beam structure in the case of acoustically anisotropic media is presented in this paper. The investigation is carried on the example of two quasi-collinear acousto-optic cells fabricated on the base of tellurium dioxide crystal...
April 2, 2017: Ultrasonics
M S Vasco, L C Alves, V Corregidor, A Bettiol, F Watt, T Pinheiro
In this work, a new tool was developed, the MORIA program that readily translates Rutherford backscattering spectrometry (RBS) output data into visual information, creating a display of the distribution of elements in a true three-dimensional (3D) environment. The program methodology is illustrated with the analysis of yeast Saccharomyces cerevisiae cells, exposed to copper oxide nanoparticles (CuO-NP) and HeLa cells in the presence of gold nanoparticles (Au-NP), using different beam species, energies and nuclear microscopy systems...
April 10, 2017: Journal of Microscopy
Ezekiel A Anyebe, I Sandall, Z M Jin, Ana M Sanchez, Mohana K Rajpalke, Timothy D Veal, Y C Cao, H D Li, R Harvey, Q D Zhuang
The recent discovery of flexible graphene monolayers has triggered extensive research interest for the development of III-V/graphene functional hybrid heterostructures. In order to fully exploit their enormous potential in device applications, it is essential to optimize epitaxial growth for the precise control of nanowire geometry and density. Herein, we present a comprehensive growth study of InAs nanowires on graphitic substrates by molecular beam epitaxy. Vertically well-aligned and thin InAs nanowires with high yield were obtained in a narrow growth temperature window of 420-450 °C within a restricted domain of growth rate and V/III flux ratio...
April 10, 2017: Scientific Reports
Roger Harrison
Out-of-field doses in radiotherapy have been increasingly studied in recent years because of the generally improved survival of patients who have received radiotherapy as part of their treatment for cancer and their subsequent risk of a second malignancy. This short article attempts to identify some current problems, challenges and opportunities for dosimetry developments in this field. Out-of-field doses and derived risk estimates contribute to general knowledge about radiation effects on humans as well as contributing to risk-benefit considerations for the individual patient...
April 6, 2017: Physica Medica: PM
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"