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An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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Molecular imaging refers to a class of noninvasive biomedical imaging techniques with the sensitivity and specificity to image biochemical variations in-vivo. An ideal molecular imaging technique visualizes a biochemical target according to a range of criteria, including high spatial and temporal resolution, high contrast relative to non-targeted tissues, depth-independent penetration into tissue, lack of harm to the organism under study, and low cost. Because no existing molecular imaging modality is ideal for all purposes, new imaging approaches are needed. Here we demonstrate a novel molecular imaging approach, called nanodiamond imaging, that uses nanodiamonds containing nitrogen-vacancy (NV) color centers as an imaging agent, and image nanodiamond targets in pieces of chicken breast. Nanodiamonds can be tagged with biologically active molecules so they bind to specific receptors; their distribution can then be quantified in-vivo via optically-detected magnetic resonance of the NVs. In effect, we are demonstrating Optically-Detected Functional-Electron-Spin-Resonance-Imaging, OD-f-ESRI. By combining optical detection with magnetic resonance, nanodiamond imaging achieves high sensitivity and high spatial resolution. It is absent of the complications of ionizing radiation, and the cost should be similar to all-optical imaging. Because nanodiamond imaging is limited by the depth of optical penetration into tissue to depths of a few cm, nanodiamond imaging should open up new avenues of investigation for applications where high depth penetration is not required, such as in small-animal imaging, tumor margin imaging, sentinel lymph node mapping, and perhaps mammography.
A Kramers‐Kronig transform that is useful for validating electrochemical and corrosion impedance data is employed to calculate the polarization resistance from the frequency‐dependent imaginary component. Applications of the transform in the analysis of experimental impedance data for carbon steel in solution at ambient temperature and for aluminum and Al‐0.1P‐0.1In‐0.2‐Ga‐0.01Tl alloy in solution at 25°C are discussed.
Absorbed sunlight in a solar cell produces electrons and holes. But, at the\nopen circuit condition, the carriers have no place to go. They build up in\ndensity and, ideally, they emit external fluorescence that exactly balances the\nincoming sunlight. Any additional non-radiative recombination impairs the\ncarrier density buildup, limiting the open-circuit voltage. At open-circuit,\nefficient external fluorescence is an indicator of low internal optical losses.\nThus efficient external fluorescence is, counter-intuitively, a necessity for\napproaching the Shockley-Queisser efficiency limit. A great Solar Cell also\nneeds to be a great Light Emitting Diode. Owing to the narrow escape cone for\nlight, efficient external emission requires repeated attempts, and demands an\ninternal luminescence efficiency >>90%.\n
Doppelbegabung: Als Säure- und Desoxydehydratisierungs(DODH)-Katalysatoren wandeln Oxorheniumverbindungen aus Biomasse erzeugte Diolsubstrate in nützliche Chemikalien um. Die Leistungsfähigkeit dieses Ansatzes belegen ein Tandemprozess aus [1,3]-OH-Verschiebung und DODH von 2-En-1,4-diolen und 2,4-Dien-1,6-diolen sowie eine DODH-Veresterungs-Sequenz, die Zuckersäuren in ungesättigte Ester als Ausgangsstoffe für Polymere und Weichmacher überführt. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Data centers deploy a variety of middleboxes (e.g., firewalls, load balancers and SSL offloaders) to protect, manage and improve the performance of applications and services they run. Since existing networks provide limited support for middleboxes, administrators typically overload path selection mechanisms to coerce traffic through the desired sequences of middleboxes placed on the network path. These ad-hoc practices result in a data center network that is hard to configure and maintain, wastes middlebox resources, and cannot guarantee middlebox traversal under network churn. To address these issues, we propose the policy-aware switching layer or PLayer, a new layer-2 for data centers consisting of inter-connected policy-aware switches or pswitches. Unmodified middleboxes are placed off the network path by plugging them into pswitches. Based on policies specified by administrators, pswitches explicitly forward different types of traffic through different sequences of middleboxes. Experiments using our prototype software pswitches suggest that the PLayer is flexible, uses middleboxes efficiently, and guarantees correct middlebox traversal under churn.
ABSTRACT Metabolic engineering and multisubunit protein production necessitate the expression of multiple genes at coordinated levels. In bacteria, genes for multisubunit proteins or metabolic pathways are often expressed in operons under the control of a single promoter; expression of the genes is coordinated by varying transcript stability and the rate of translation initiation. We have developed a system to place multiple genes under the control of a single promoter and produce proteins encoded in that novel operon in different ratios over a range of inducer concentrations. RNase E sites identified in the Rhodobacter capsulatus puf operon and Escherichia coli pap operon were separately placed between the coding regions of two reporter genes, and novel secondary structures were engineered into the 5′ and 3′ ends of the coding regions. The introduced RNase E site directed cleavage between the coding regions to produce two secondary transcripts, each containing a single coding region. The secondary transcripts were protected from exonuclease cleavage by engineered 3′ secondary structures, and one of the secondary transcripts was protected from RNase E cleavage by secondary structures at the 5′ end. The relative expression levels of two reporter genes could be varied up to fourfold, depending on inducer concentration, by controlling RNase cleavage of the primary and secondary transcripts. Coupled with the ability to vary translation initiation by changing the ribosome binding site, this technology should allow one to create new operons and coordinate, yet separately control, the expression levels of genes expressed in that operon.
