Since the discovery of frozen megafauna carcasses in Northern Siberia and Alaska early 1800s, Yedoma phenomenon has attracted many Arctic explorers scientists. Exposed along coastal riverbank bluffs, often appears as large masses ice with some inclusions sediment. The ground particularly mystified geologists geographers, they considered sediment within exposures to be a secondary unimportant co...

Irregular body contour and tumor volumes necessitate beam modi iers such as physical wedges to achieve a better uniformity of dose distribution (1‐3). With the increasing interest in intensity modulated radiation therapy (IMRT), using of physical wedges has been reduced for ield shaping. On the other hand, IMRT includes a small fraction of the overall treatment techniques for several reasons su...

Dose inhomogeneity in treatment planning can be compensated using physical wedges. Enhanced dynamic wedges (EDW) were introduced by Varian to overcome some of the shortcomings of physical wedges. The objectives of this study were to measure EDW output factors for 6 MV and 20 MV photon energies for a Varian 2300CD. Secondly, to review the literature in terms of published enhanced dynamic wedge o...

INTRODUCTION The mechanical environment of the knee during walking can influence both the health and breakdown of the knee cartilage. With walking being the most common activity of daily living as well as producing a cyclically reproducible pattern of loading a close link to the maintenance of healthy knee cartilage is indicated.(1) Normally 60–80% of the total intrinsic compressive load transm...

BACKGROUND Opening wedge high tibial osteotomy often requires bone grafting to improve the union rate and avoid instability at the osteotomy site. Autograft and allograft have both been associated with complications and the use of bone substitute wedges has been advocated to improve the outcome. This study investigated the clinical, radiological and histological outcomes of using biphasic calci...

The Radiological Physics Center, through its dosimetry review visits to participating institutions, is aware that many institutions ignore the field-size and depth dependence of wedge transmission values. Reference wedge transmission values are normally measured by the Radiological Physics Center for a 10 cm x 10 cm field at the calibration depth of 5 or 7 cm. Recently, additional measurements ...

OBJECTIVES To present a simplified calculation for the measurement of osteotomy wedges used for the correction of angular uniplanar deformities of long bones and to compare the simplified calculation proposed (circumferential calculation) with the classical trigonometric calculations, as well as with the exact calculation performed by computer software AutoCADtm. METHODS The software AutoCADt...

Radiation therapy treatment planning for many clinical situations requires wedgeshaped isodose distributions. The wedged dose distributions can be generated through the use of physical wedges (PWs), motorized wedges and the synchronization of jaw or multileaf collimator dynamic motion with accelerator dose output. Modern medical accelerators are usually equipped with a dynamic wedge (DW) option...

We present a polarization shaping technique for few-cycle terahertz (THz) waves. For this, N femtosecond laser pulses are generated from a devised diffractive optical system made of as-many glass wedges, which then simultaneously illuminate on various angular positions of a sub-wavelength circular pattern of an indium arsenide thin film, to produce a THz wave of tailor-made polarization state g...

A bifield stimulation method for rapidly obtaining retinotopic maps in human occipital cortex using functional MRI was compared to conventional unifield stimulation. While maintaining central fixation, each participant viewed the conventional display, consisting of a single rotating checkerboard wedge and, in a separate run, the bifield display, consisting of two symmetrically placed rotating c...