Eukaryotic cells have found a nifty way of compacting this long strand into a more manageable size so that a cell can easily contain it. By wrapping portions of the DNA around histone octamers, the primary level of compactness is reached, which forms the basic building block of chromatin. Access to any portion of the DNA strand is ensured by continual remodeling of the chromatin structure, whereby small access sites are created and closed shortly after – just long enough for the cell to read that portion of the genetic code.

Spin coating is a standard technique, commonly used to prepare organic thin films from a solution. In order to achieve high-performance optoelectronic devices, such as solar cells based on spin-coated organic semiconductors, there is a need to control the structure, the morphology and the degree of phase separation of the organic semiconductor.

Printers, cassette recorders, and DVD players are chock full of parts—motors, lights, gears, switches, buttons, pulleys, belts, liquid crystal displays, and speakers—that employ standards-worthy concepts of physics, mathematics, and engineering. It’s undeniably captivating to examine the design of these intricate systems, it’s exciting to bring the components back to life, and it’s fun to get creative building something new.

WebsEdge is an international company specializing in providing educational TV channels at technical conferences. A production crew visited CHESS on January 14, conducting interviews and recording activities here. Through highly skilled editing, the resulting several hours of “footage” was distilled down into a 5-minute video presenting the essence of MacCHESS to the public. We retain the raw recordings for use in future presentations.

Full spatial coherence is highly sought after because as a light source approaches that level of perfection, new x-ray probes and techniques become possible such as coherent diffraction imaging (CDI), x-ray photon correlation spectroscopy (XPCS), as well as enabling efficient focusing by Fresnel lenses to create diffraction limited beam-waists. One of the simplest ways to start thinking about coherence is to realize that the x-ray beam produced by a single electron passing through an undulator is completely coherent.

Ellipsoid shaped single-bounce glass capillaries fabricated at CHESS have been used as achromatic X-ray focusing optics for various applications at synchrotron beamlines, such as microbeam X-ray fluorescence and tomography, confocal X-ray microscopy, microbeam small-angle X-ray scattering (µSAXS), microbeam high-resolution X-ray diffraction and standing wave technique, high pressure studies with diamond anvil cells, microbeam grazing-incidence wide-angle X-ray scattering (µGIWAXS), full-field transmission X-ray microscopy (TXM), X-ray emission spectroscopy and microcrystallography.

The first workshop of its kind was hosted by the American Association for the Advancement of Science, aimed at helping science educators understand how these national science standards will impact K-12 education. NGSS encompass an ongoing science education reform initiative launched in the late 1980's aimed at improving the quality, relevance and availability of STEM. NGSS represent a set of goals for our nation, outlining what educators expect students to be able to do and understand after completing secondary school, building a foundation for their post-secondary education in STEM.

The crews are currently working in concert with each other, moving from east to west through the L-0 experimental hall.  When a new magnet assembly goes in, the crews place a new portion of shielding wall, then a new front end assembly, followed by utilities and more portions of shielding wall - creating a dance that requires strict planning while donning steel-toed boots. 

The extraordinary properties of diamond, such as radiation hardness and high thermal conductivity, make it an ideal material for synchrotron X-ray radiation detectors. The heart of the detector is based on a high purity single crystal diamond in the shape of a small square wafer approximately 0.1 - 0.5 mm thick.