The availability of well-characterized neuroimaging data with large numbers of subjects, especially for clinical populations, is critical to advancing our understanding of the healthy and diseased brain. Such data enables questions to be answered in a much more generalizable manner and also has the potential to yield solutions derived from novel methods that were conceived after the original studies’ implementation. Though there is currently growing interest in data sharing, the neuroimaging community has been struggling for years with how to best encourage sharing data across brain imaging studies. With the advent of studies that are much more consistent across sites (e.g., resting functional magnetic resonance imaging, diffusion tensor imaging, and structural imaging) the potential of pooling data across studies continues to gain momentum. At the mind research network, we have developed the collaborative informatics and neuroimaging suite (COINS; ) to provide researchers with an information system based on an open-source model that includes web-based tools to manage studies, subjects, imaging, clinical data, and other assessments. The system currently hosts data from nine institutions, over 300 studies, over 14,000 subjects, and over 19,000 MRI, MEG, and EEG scan sessions in addition to more than 180,000 clinical assessments. In this paper we provide a description of COINS with comparison to a valuable and popular system known as XNAT. Although there are many similarities between COINS and other electronic data management systems, the differences that may concern researchers in the context of multi-site, multi-organizational data sharing environments with intuitive ease of use and PHI security are emphasized as important attributes.

Purpose:To evaluate the feasibility of using a commercially available clinical dual-energy computed tomographic (CT) scanner to differentiate the in vivo enhancement due to two simultaneously administered contrast media with complementary x-ray attenuation ratios. Materials and Methods:Approval from the institutional animal care and use committee was obtained, and National Institutes of Health guidelines for the care and use of laboratory animals were observed. Dual-energy CT was performed in a set of iodine and tungsten solution phantoms and in a rabbit in which iodinated intravenous and bismuth subsalicylate oral contrast media were administered. In addition, a second rabbit was studied after intravenous administration of iodinated and tungsten cluster contrast media. Images were processed to produce virtual monochromatic images that simulated the appearance of conventional single-energy scans, as well as material decomposition images that separate the attenuation due to each contrast medium. Results:Clear separation of each of the contrast media pairs was seen in the phantom and in both in vivo animal models. Separation of bowel lumen from vascular contrast medium allowed visualization of bowel wall enhancement that was obscured by intraluminal bowel contrast medium on conventional CT scans. Separation of two vascular contrast media in different vascular phases enabled acquisition of a perfectly coregistered CT angiogram and venous phaseenhanced CT scan simultaneously in a single examination. Conclusion:Commercially available clinical dual-energy CT scanners can help differentiate the enhancement of selected pairs of complementary contrast media in vivo.

Dispersions of carbon nanotube salts prepared by treating single-walled carbon nanotubes (SWNTs) with lithium in liquid ammonia react with aryl and alkyl sulfides by single electron transfer (SET) to yield transient radical anions that dissociate into carbon-centered free radicals and mercaptide. The free radicals add to the sidewalls of the nanotubes or recombine with SWNT radical anions. AFM images indicate that the derivatized SWNTs are partially debundled. Disulfides react with carbon nanotube salts to yield SWNTs functionalized by sulfur-centered radicals.

Neuroimaging data collection is inherently expensive. Maximizing the return on investment in neuroimaging studies requires that neuroimaging data be re-used whenever possible. In an effort to further scientific knowledge, the COINS Data Exchange (DX) (http://coins.mrn.org/dx) aims to make data sharing seamless and commonplace. DX takes a three-pronged approach towards improving the overall state of data sharing within the neuroscience community. The first prong is compiling data into one location that has been collected from all over the world in many different formats. The second prong is curating the data so that it can be stored in one consistent format and so that data QA/QC measures can be assured. The third prong is disseminating the data so that it is easy to consume and straightforward to interpret. This paper explains the concepts behind each prong and describes some challenges and successes that the Data Exchange has experienced.

Single-walled carbon nanotubes (SWNTs) induce the decomposition of four diacyl peroxides by single electron transfer (SET). Phthaloyl peroxide functionalizes SWNTs to the greatest extent of the four. It was also found that t-butoxy radicals add to SWNTs but that SWNTs fail to inhibit cumene autoxidation. Thus, SWNTs are reactive to alkoxy radicals but not to alkylperoxy radicals.The great potential value of functionalizing single-walled nanotubes (SWNTs) has led a number of workers to explore free radical attack on the sidewalls of these unique nanometersized objects. 1,2 The most common radical precursors are diazonium salts 3 and peroxides, 4-8 but other approaches are based on Fenton's reagent, 6 perfluoroalkyl iodides, 9,10 perfluoro azo compounds, 11,12 microwave discharge of ammonia, 13 and attack of growing polymer chains. 14 Presently, we report the kinetics of diacyl peroxide thermolysis in the presence of SWNTs, which reveal moderate to large rate accelerations attributed to induced decomposition. We further report the attack of t-butoxy radicals on SWNTs and the failure of SWNTs to inhibit the autoxidation of cumene.While studying the thermolysis of benzoyl peroxide (BP) with SWNTs, we noticed that the rate of gas evolution, as monitored by a pressure transducer, was accelerated by inclusion of purified, pristine HiPco SWNTs. 15 Thus, a solution of 75 mg BP in 10 mL ortho-dichlorobenzene (o-DCB) exhibited a 67% greater pressure rise over the course of 2 h at 80°C when SWNTs (5 mg) were included than a control experiment without SWNTs. This rate enhancement was confirmed by iodometric titration 16 of the BP remaining after thermolysis. All titration studies discussed below were performed in non-degassed o-DCB using purified HiPCo SWNTs batch no. 164-2 produced in the Rice University Carbon Nanotechnology Laboratory. 17 Comparison of non-degassed with degassed o-DCB gave essentially the same percent peroxide decomposition whether SWNTs were present or not. Figure 1 shows the percent BP consumed in 1 h at 80°C and 90°C in 50 mL o-DCB as the initial weight of SWNTs was increased from 0 to 5 mg. Although the rate enhancement due to SWNTs is apparent, a number of control experiments were required. The thermolysis of 0.006 M BP in o-DCB at 80°C is slow enough that hardly any decomposition (∼1%/hr) was detectable. We ran the thermolysis in benzene as a control and obtained about 6%/hr decomposition, corresponding to the rate reported in the literature. 18,19 Therefore o-DCB does not induce BP thermolysis as much as benzene does and no correction was needed for residual thermolysis at 80°C. (cf. Figure 1). However, at 90°C BP in o-DCB thermolyzes at a moderate rate, as evidenced by the 17% decomposed in 1 h even without added SWNTs. The steep rise in % BP consumed at low [SWNT] is seen in most runs where normal peroxide thermolysis was important. After this initial jump, BP consumption rises more or less linearly with increasing amounts of SWNTs.The same effect was observed in p-methoxybenzoyl peroxide (p-MeO-...