345 research outputs found

    Community Informatics: A bibliometric study of scholarly influence

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    Community Informatics is both a study and a practice that seeks to facilitate socioeconomic empowerment through the use of Information and Communication Technologies, such as the Internet. As a developing area of interdisciplinary scholarship, Community Informatics has not yet been defined in academic terms. Using a bibliometric method, the intention of this study is to reveal the scholarly influences for this emerging area of academic scholarship. In order to examine the foundations of this scholarly community, this study evaluated citation patterns from the first year of publication of The Journal of Community Informatics, the sole and seminal peerreviewed serial publication in this research area. The results of this study make an important and necessary contribution that will help to more accurately characterize the intellectual home for Community Informatics

    Structural studies of Perfluoroaryldiselenadiazolyl Radicals: Insights into Dithiadiazolyl Chemistry

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    Synopsis Diselenadiazolyls exhibit a stronger tendency to dimerize in the solid state than their corresponding dithiadiazolyl (DTDA) radicals, reflected in a range of dimerization modes for (p-XC6F4CNSeSeN)2, which contrast with those of the monomeric DTDA radicals, p-XC6F4CNSSN. The structure of (p-NCC6F4CNSeSeN)2 reflects a buildup of molecular strain in order to accommodate both dimerization and structure-directing CN···Se contacts, whereas the suppression of dimerization releases molecular strain yet retains structure-directing CN···S contacts for the corresponding DTDA radical

    Accelerated and increased joint damage in young mice with global inactivation of mitogen-inducible gene 6 after ligament and meniscus injury

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    Abstract Introduction Ligament and meniscal damage can cause joint disease. Arthritic joints contain increased amounts of epidermal growth factor receptor (EGFR) protein, and polymorphisms in EGFR are associated with arthritis risk. The role of endogenous EGFR regulation during joint disease due to ligament and meniscal trauma is unknown. Mitogen-inducible gene 6 (MIG-6) can reduce EGFR phosphorylation and downstream signaling. We examined the effect of EGFR modulation by MIG-6 on joint disease development after ligament and meniscus injury. Methods Knee ligament transection and meniscus removal were performed surgically on mice homozygous for a global inactivating mutation in MIG-6 (Mig-6 −/− ) and in wild-type (WT) animals. Results Two weeks after surgery, Mig-6 −/− mice had bone erosion as well as greater fibrous tissue area and serum RANKL concentration than WT mice. Four weeks after surgery, Mig-6 −/− mice had less cartilage and increased cell proliferation relative to contralateral control and WT knees. Increased apoptotic cells and growth outside the articulating region occurred in Mig-6 −/− mice. Tibia trabecular bone mineral density (BMD) and the number of trabeculae were lower in surgically treated knees relative to the respective control knees for both groups. BMD, as well as trabecular thickness and number, were lower in surgically treated knees from Mig-6 −/− mice relative to WT surgically treated knees. Phosphorylated EGFR staining in surgically treated knees decreased for WT mice and increased for Mig-6 −/− mice. Fewer inflammatory cells were present in the knees of WT mice. Conclusion Mig-6 −/− mice have rapid and increased joint damage after ligament and meniscal trauma. Mig-6 modification could lessen degenerative disease development after this type of injury.http://deepblue.lib.umich.edu/bitstream/2027.42/109507/1/13075_2013_Article_4169.pd

    CFD Investigation on Fluid Flow Analysis in Fluid Separator

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    The analysis of fully developed flow in the two fluid separators is an important issue in the industry such as production, processing, and petrochemical. The role of the two fluid separator is to separate two different fluid by using an appropriate mechanism without changing the quality. In this study, we have reviewed different mechanisms of two fluid separations such as gravity sedimentation, centrifugation, and electro kinetics, etc. The current work focuses on the design aspect of a fluid separator with respect to geometry and thermal design. CFD has been used to simulate flow in a fluid separator and its results have been verified experimentally. Flow rates used in the simulation have different values in interval 0.1 LPM. The study shows the best performance of fluid separator with respect to shape and flow rates. The given work helps to co-relate various design of separator in the industry with laboratory separators

    Tumor Invasion of Salmonella enterica Serovar Typhimurium Is Accompanied by Strong Hemorrhage Promoted by TNF-α

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    BACKGROUND:Several facultative anaerobic bacteria with potential therapeutic abilities are known to preferentially colonize solid tumors after systemic administration. How they efficiently find and invade the tumors is still unclear. However, this is an important issue to be clarified when bacteria should be tailored for application in cancer therapy. METHODOLOGY/PRINCIPAL FINDINGS:We describe the initial events of colonization of an ectopic transplantable tumor by Salmonella enterica serovar Typhimurium. Initially, after intravenous administration, bacteria were found in blood, spleen, and liver. Low numbers were also detected in tumors associated with blood vessels as could be observed by immunohistochemistry. A rapid increase of TNF-alpha in blood was observed at that time, in addition to other pro-inflammatory cytokines. This induced a tremendous influx of blood into the tumors by vascular disruption that could be visualized in H&E stainings and quantified by hemoglobin measurements of tumor homogenate. Most likely, together with the blood, bacteria were flushed into the tumor. In addition, blood influx was followed by necrosis formation, bacterial growth, and infiltration of neutrophilic granulocytes. Depletion of TNF-alpha retarded blood influx and delayed bacterial tumor-colonization. CONCLUSION:Our findings emphasize similarities between Gram-negative tumor-colonizing bacteria and tumor vascular disrupting agents and show the involvement of TNF-alpha in the initial phase of tumor-colonization by bacteria

    High Interstitial Fluid Pressure Is Associated with Tumor-Line Specific Vascular Abnormalities in Human Melanoma Xenografts

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    PURPOSE: Interstitial fluid pressure (IFP) is highly elevated in many solid tumors. High IFP has been associated with low radiocurability and high metastatic frequency in human melanoma xenografts and with poor survival after radiation therapy in cervical cancer patients. Abnormalities in tumor vascular networks have been identified as an important cause of elevated tumor IFP. The aim of this study was to investigate the relationship between tumor IFP and the functional and morphological properties of tumor vascular networks. MATERIALS AND METHODS: A-07-GFP and R-18-GFP human melanomas growing in dorsal window chambers in BALB/c nu/nu mice were used as preclinical tumor models. Functional and morphological parameters of the vascular network were assessed from first-pass imaging movies and vascular maps recorded after intravenous bolus injection of 155-kDa tetramethylrhodamine isothiocyanate-labeled dextran. IFP was measured in the center of the tumors using a Millar catheter. Angiogenic profiles of A-07-GFP and R-18-GFP cells were obtained with a quantitative PCR array. RESULTS: High IFP was associated with low growth rate and low vascular density in A-07-GFP tumors, and with high growth rate and high vascular density in R-18-GFP tumors. A-07-GFP tumors showed chaotic and highly disorganized vascular networks, while R-18-GFP tumors showed more organized vascular networks with supplying arterioles in the tumor center and draining venules in the tumor periphery. Furthermore, A-07-GFP and R-18-GFP cells differed substantially in angiogenic profiles. A-07-GFP tumors with high IFP showed high geometric resistance to blood flow due to high vessel tortuosity. R-18-GFP tumors with high IFP showed high geometric resistance to blood flow due to a large number of narrow tumor capillaries. CONCLUSIONS: High IFP in A-07-GFP and R-18-GFP human melanoma xenografts was primarily a consequence of high blood flow resistance caused by tumor-line specific vascular abnormalities

    Application of prolonged microdialysis sampling in carboplatin-treated cancer patients

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    Purpose: To better understand the mechanisms underlying (in)sensitivity of tumors to anticancer drugs, assessing intra-tumor drug pharmacokinetics (PKs) could be important. We explored the feasibility of microdialysis in tumor tissue for multiple days in a clinical setting, using carboplatin as model drug. Methods: Plasma and microdialysate samples from tumor and adipose normal tissues were collected up to 47 h after dosing in eight carboplatin-treated patients with an accessible (sub)cutaneous tumor. Results: Pharmacokinetics were evaluable in tumor tissue in 6/8 patients and in adipose normal tissue in 3/8 patients. Concentration-time curves of unbound platinum in both the tissues followed the pattern of the curves in plasma, with exposure ratios of tissue versus plasma ranging from 0.64 to 1.46. Conclusions: Microdialysis can be successfully employed in ambulant patients for multiple days, which enables one to study tissue PK of anticancer drugs in normal and malignant tissues in more detail

    Spin density studies on p-O2NC6F4CNSSN: A heavy p-block organic ferromagnet

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    A complete picture of the spin density distribution in the organic radical p-O2NC6F4CNSSN has been obtained by a combination of polarized neutron diffraction, electron paramagnetic resonance (EPR), and electron-nuclear double resonance (ENDOR) spectroscopies, and ab initio density-functional theory (DFT) calculations. Polarized neutron diffraction revealed that the spin distribution is predominantly localized on the N and S atoms (+0.25μB and +0.28μB, respectively) of the heterocyclic ring with a small negative spin density on the heterocyclic C atom (−0.06μB). These spin populations are in excellent agreement with both ab initio DFT calculations (spin populations on the C, N, and S sites of −0.07, 0.22 and 0.31, respectively) and cw-EPR studies which estimated the spin population on the N site as 0.24. The DFT calculated spin density revealed less than 1% spin delocalization onto the perfluoroaryl ring, several orders of magnitude lower than the density on the heterocyclic ring. cw-ENDOR studies at both X-band (9 GHz) and Q-band (34 GHz) frequencies probed the spin populations on the two chemically distinct F atoms. These spin populations on the F atoms ortho and meta to the dithiadiazolyl ring are of magnitude 10−3 and 10−4, respectively
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