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Kuang Y, Pratx G, Meng B, Qian J, Bazalova M, Xing L. TH-A-213CD-02: BEST IN PHYSICS (IMAGING) - The Feasibility of Multiplexed Biomarker Detection Using X-Ray Stimulated Fluorescence Imaging. Med Phys 2012. [DOI: 10.1118/1.4736264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Bar-Natan M, Nelson EA, Walker SR, Kuang Y, Distel RJ, Frank DA. Dual inhibition of Jak2 and STAT5 enhances killing of myeloproliferative neoplasia cells. Leukemia 2011; 26:1407-10. [DOI: 10.1038/leu.2011.338] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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78
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Kuang Y, Weng X, Liu X, Zhu H, Chen Z, Chen H. Effects of 4-1BB signaling on the biological function of murine dendritic cells. Oncol Lett 2011; 3:477-481. [PMID: 22740935 DOI: 10.3892/ol.2011.506] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 11/14/2011] [Indexed: 11/06/2022] Open
Abstract
4-1BB signaling has profound effects on the T cell-induced cell immune response, but its biological function in dendritic cells (DCs) has remained largely uncharacterized. In this study, we investigated the function of 4-1BB in murine DCs with an agonistic mAb to 4-1BB. Interleukin (IL)-6 and IL-12 production was assessed by an enzyme-linked immunosorbent assay (ELISA). Co-stimulatory molecules (CD80 and CD86) in DCs were analyzed by flow cytometry. The results showed that 4-1BB was strongly expressed in DCs during the maturation process. Triggering 4-1BB increased the secretion of IL-6 and IL-12 and the upregulation of co-stimulatory molecules (CD80 and CD86) from DCs, indicating that agonistic mAb to 4-1BB directly improves the activation of DCs. Moreover, triggering 4-1BB induced a higher survival rate of DCs compared to that of hamster IgG isotype control, due to the upregulated expression of Bcl-2 and Bcl-xL. To further assess the role of 4-1BB on DCs stimulating T-cell proliferation, allogeneic mixed lymphocyte reactions were analyzed. The agonistic anti-4-1BB mAb induced a higher T-cell proliferation. These results suggest that 4-1BB affects the duration, DC-T interaction and immunogenicity of DCs.
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Zhang LL, Wang JJ, Liu Y, Lu XB, Kuang Y, Wan YH, Chen Y, Yan HM, Fei J, Wang ZG. GPR26-deficient mice display increased anxiety- and depression-like behaviors accompanied by reduced phosphorylated cyclic AMP responsive element-binding protein level in central amygdala. Neuroscience 2011; 196:203-14. [DOI: 10.1016/j.neuroscience.2011.08.069] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Revised: 08/21/2011] [Accepted: 08/31/2011] [Indexed: 01/27/2023]
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Kuang Y, Pratx G, Sun C, Carpenter C, Xing L. TU-A-301-08: X-Ray Stimulated Fluorescence for Breast Imaging. Med Phys 2011. [DOI: 10.1118/1.3613098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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81
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Weng X, Kuang Y, Liu X, Chen Z, Zhu H, Chen H, Jiang B, Shen H. Construction of a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen and mouse 4-1BBL genes and its effect on dendritic cells. Braz J Med Biol Res 2011; 44:186-92. [PMID: 21243315 DOI: 10.1590/s0100-879x2011007500002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 12/17/2010] [Indexed: 11/21/2022] Open
Abstract
Our aim was to construct a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen (tPSMA) and mouse 4-1BBL genes and to determine its effect on dendritic cells (DCs) generated from bone marrow suspensions harvested from C57BL/6 mice for which the effect of 4-1BBL on DCs is not clear, especially during DCs processing tumor-associated antigen. Replication deficient adenovirus AdMax™ Expression System was used to construct recombinant adenovirus Ad-tPSMA-internal ribosome entry site-mouse 4-1BBL (Ad-tPSMA-IRES-m4-1BBL) and Ad-enhanced green fluorescent protein. Day 7 proliferating DC aggregates generated from C57BL/6 mice were collected as immature DCs and further mature DCs were obtained by lipopolysaccharide activated immature DCs. After DCs were exposed to the recombinant adenovirus with 250 multiplicity of infection, the expression of tPSMA and m4-1BBL proteins were detected by Western blot, and the apoptosis and phenotype of DCs were analyzed by flow cytometry. Cytokines (IL-6 and IL-12) in the supernatant were detected by enzyme-linked immunosorbent assay (ELISA). Proliferation of T cells was detected by allogeneic mixed lymphocyte reactions. The tPSMA and m4-1BBL proteins were expressed correctly. The apoptosis rate of DCs transfected with Ad-tPSMA-IRES-m4-1BBL was 14.6%, lower than that of control DCs. The expression of co-stimulatory molecules [CD80 (81.6 ± 5.4%) and CD86 (80.13 ± 2.81%)] up-regulated in Ad-tPSMA-IRES-m4-1BBL-pulsed DCs, and the level of IL-6 (3960.2 ± 50.54 pg/mL) and IL-12 (249.57 ± 12.51 pg/mL) production in Ad-tPSMA-IRES-m4-1BBL-transduced DCs were significantly higher (P < 0.05) than those in control DCs. Ad-tPSMA-IRES-m4-1BBL induced higher T-cell proliferation (OD(450) = 0.614 ± 0.018), indicating that this recombinant adenovirus can effectively enhance the activity of DCs.
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Xue S, Lyu Q, Peng Q, Cao S, Zhou Y, Kuang Y. Vitrification yields superior efficiency of human cleavage-stage embryo cryopreservation versus slow-freezing. Fertil Steril 2010. [DOI: 10.1016/j.fertnstert.2010.07.486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Zamiri P, Kuang Y, Sharma U, Ng TF, Busold RH, Rago AP, Core LA, Palasis M. The biocompatibility of rapidly degrading polymeric stents in porcine carotid arteries. Biomaterials 2010; 31:7847-55. [PMID: 20696471 DOI: 10.1016/j.biomaterials.2010.06.057] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Accepted: 06/28/2010] [Indexed: 11/19/2022]
Abstract
The goal of this study was to evaluate the biocompatibility of materials for use in fully bioabsorbable vascular stents. 10:90 poly(L-lactic-co-glycolic acid) (10:90 L-PLGA), 85:15 poly(L-lactic-co-glycolic acid) (85:15 L-PLGA), polydioxanone (PDO), and poly-L-lactic acid (L-PLA) polymers were chosen as materials. Polymeric fibers were woven into a braided structure with a mass equivalent to or greater than that expected for a vascular stent, secured to balloon-expandable bare metal stents and implanted into porcine carotid arteries. The in vivo response was analyzed at 30 and 90 days by angiography, histopathology, and histomorphometry. All vessels were patent at 30 and 90 days. Injury score and neointima formation was mild for all samples. The faster-degrading 10:90 L-PLGA had the highest inflammatory response at 30 days, but was completely absorbed with minimal inflammation and neointimal formation at 90 days. PDO showed signs of partial absorption at 90 days, while 85:15 L-PLGA and L-PLA demonstrated minimal absorption at 30 and 90 days. The inflammatory response to these three groups was similar over the experimental period. Using a robust materials-testing platform, we demonstrated long-term patency and intravascular biocompatibility of bioabsorbable polymers with varying rates of resorption. The data point to biocompatibility of a polymeric stent in the vascular space that is fully absorbable in less than a year.
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Gu J, Yang W, Cheng J, Yang T, Qu Y, Kuang Y, Huang H, Yang L, He W, Min L. Temporal and spatial characteristics and treatment strategies of traumatic brain injury in Wenchuan earthquake. Emerg Med J 2010; 27:216-9. [DOI: 10.1136/emj.2008.065342] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kuang Y, Weng X, Liu X, Zhu H, Chen Z, Jiang B, Chen H. Anti-tumor immune response induced by dendritic cells transduced with truncated PSMA IRES 4-1BBL recombinant adenoviruses. Cancer Lett 2010; 293:254-62. [PMID: 20149524 DOI: 10.1016/j.canlet.2010.01.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 12/28/2009] [Accepted: 01/17/2010] [Indexed: 10/19/2022]
Abstract
Up-regulation of receptor-ligand pairs during interaction of a peptide-bound MHC complex on dendritic cells (DCs) with cognate TCR may amplify, sustain, and drive diversity in the ensuing T cell immune response. Members of the TNF ligand superfamily and the TNFR superfamily contribute to this costimulatory molecule signaling. In the present study, we used replication deficient adenoviruses to introduce a tumor-associated Ag (a truncated human prostate-specific membrane antigen (tPSMA)) and the T cell costimulatory molecule 4-1BBL into murine DCs, and observed the ability of these recombinant DCs to elicit tPSMA-directed T-cell responses in vitro and anti-tumor immunity to RM-1-tPSMA in a murine tumor model. Infection of DCs with Ad-tPSMA-IRES-m4-1BBL induced tPSMA-specific proliferative responses and up-regulated CD80 and CD86 s signaling molecules. The cytotoxic T lymphocytes activated by the Ad-tPSMA-IRES-m4-1BBL-transfected DCs showed significantly higher IFN-gamma production and cytotoxicity against the RM-1 cells transfected with tPSMA. Moreover, vaccination of mice with Ad-tPSMA-IRES-m4-1BBL-transfected DCs induced a potent protective and therapeutic anti-tumor immunity to RM-1-tPSMA in a tumor model. These results demonstrated that development of DCs engineered to express tPSMA and 4-1BBL by recombinant adenovirus-mediated gene transfer may offer a new strategy for prostate cancer immunotherapy.
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Kuang Y, Ma C, Dong C, Zeng Z. UP-1.147: Clinical Report of 45 Living Related Donor Kidneys Transplantation. Urology 2009. [DOI: 10.1016/j.urology.2009.07.594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Eikenberry SE, Sankar T, Preul MC, Kostelich EJ, Thalhauser CJ, Kuang Y. Virtual glioblastoma: growth, migration and treatment in a three-dimensional mathematical model. Cell Prolif 2009; 42:511-28. [PMID: 19489983 DOI: 10.1111/j.1365-2184.2009.00613.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES Glioblastomas are aggressive primary brain cancers that are characterized by extensive infiltration into the brain and are highly resistant to treatment. Through mathematical modelling, we model the process of invasion and predict the relative importance of mechanisms contributing to malignant invasion. Clinically, we predict patterns of tumour recurrence following various modes of therapeutic intervention. MATERIALS AND METHODS Our mathematical model uses a realistic three-dimensional brain geometry and considers migrating and proliferating cells as separate classes. Several mechanisms for infiltrative migration are considered. Methods are developed for simulating surgical resection, radiotherapy and chemotherapy. RESULTS The model provides clinically realistic predictions of tumour growth and recurrence following therapeutic intervention. Specific results include (i) invasiveness is governed largely by the ability of glioblastoma cells to degrade and migrate through the extracellular matrix and the ability of single migrating cells to form colonies; (ii) tumours originating deeper in the brain generally grow more quickly than those of superficial origin; (iii) upon surgery, the margins and geometry of resection significantly determine the extent and pattern of postoperative recurrence; (iv) radiotherapy works synergistically with greater resection margins to reduce recurrence; (v) simulations in both two- and three-dimensional geometries give qualitatively similar results; and (vi) in an actual clinical case comprising several surgical interventions, the model provides good qualitative agreement between the simulated and observed course of the disease. CONCLUSIONS The model provides a useful initial framework by which biological mechanisms of invasion and efficacy of potential treatment regimens may be assessed.
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Salem N, Kuang Y, Wang F, Maclennan GT, Lee Z. PET imaging of hepatocellular carcinoma with 2-deoxy-2[18F]fluoro-D-glucose, 6-deoxy-6[18F] fluoro-D-glucose, [1-11C]-acetate and [N-methyl-11C]-choline. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2009; 53:144-156. [PMID: 19039303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
AIM This study was designed to investigate the performance of positron emission tomography (PET) imaging for hepatocellular carcinoma (HCC) on a hepatitis viral infection-induced woodchuck model using existing tracers such as 2-deoxy-2[(18)F]fluoro-D-glucose (2FDG), 6-deoxy-6[(18)F]fluoro-D-glucose (6FDG), [1(-11)C]acetate (acetate) and [N-methyl(-11)C]choline (choline). METHODS Fourteen woodchucks with HCC were imaged with different radiotracers: 13 (10 with HCC and 3 controls) with 2FDG; 4 (3 with HCC and 1 control) with 6FDG; 13 (10 with HCC and 3 controls) with acetate; 4 (2 with HCC and 2 controls) with choline. The woodchucks were euthanized after imaging experiments and liver tissues were harvested for histology, for enzymatic activities including hexokinase (HK), glucose-6-phosphatase, acetyl-CoA synthetase (ACAS) and choline kinase (CK), and for differential gene expressions between the HCCs and the surrounding hepatic tissues. RESULTS 2FDG detected 7/13 tumors with a tumor-to-liver uptake ratio (T/L) of 1.36+/-0.13. Five of these HCCs were moderately- or poorly-differentiated. The HK/glucose-6-phosphatase ratio was significantly higher in HCCs compared to the surrounding liver tissues (P=0.05). None of the HCCs imaged with 6FDG were detected by PET (T/L=1.01+/-0.11). Acetate detected 16/17 HCCs (T/L=2.02+/-0.7). ACAS activity was significantly higher in HCCs (P=0.01) and lipids-related genes were found up-regulated. Choline imaging detected all HCCs (T/L=1.63+/-0.34). CK activity was significantly higher in HCCs (P=0.001). CONCLUSIONS Well-differentiated and some moderately-differentiated HCCs do not uptake 2FDG more than the surrounding liver tissues, but display increased acetate uptake. There is no contrast between HCCs and the surrounding liver tissues on the 6FDG PET images. Despite elevated background signal from the liver, choline uptake seems to be detectable in the HCCs scanned in this study.
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Holmes A, Joshi VA, Kuang Y, Rogers A, Jänne PA. Comparison of genotyping with direct sequencing as a method to detect EGFR mutations in NSCLC. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.22013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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90
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Borras AM, Rogers A, Kuang Y, Flores L, Distel R, Krop IE. Identification of novel HER2 splice variants in breast cancer. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.22010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Kuang Y, Rogers A, Wang L, Makrigiorgos M, Vetrand K, Thiede S, Distel R, Janne PA. Non-invasive detection of EGFR T790M in gefitinib/erlotinib resistant NSCLC. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.8075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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92
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Borras AM, Kuang Y, Rogers AM, Holmes AJ, Gallegos Ruiz M, Joshi VA, Distel RJ, Giaccone G, Taron M, Janne PA. Detection of clinically significant mutations in the epidermal growth factor receptor missed by direct sequencing using a highly sensitive DNA endonuclease. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.10054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
10054 Background: Mutations in the epidermal growth factor receptor (EGFR) are associated with sensitivity and resistance to EGFR inhibitors gefitinib and erlotinib in patients with non-small cell lung carcinoma (NSCLC). Direct sequencing is currently used for mutation detection but sensitivity is limited and requires dissection to obtain a relatively pure population of tumor cells. We examined a DNA endonuclease, SURVEYOR, which cleaves mismatched heteroduplexed DNA, as a more sensitive method for EGFR mutation screening and compared it to direct sequencing. Methods: EGFR exons 18–21 from tumor DNA were amplified using PCR, digested with SURVEYOR, and the products analyzed by HPLC. Specimens that produced digestion products were re-analyzed by size separation or by denaturing HPLC followed by fractionation and sequencing. Tumor specimens from 191 NSCLC patients were analyzed: 61 frozen tumors specimens; 91 dissected formalin fixed paraffin embedded (FFPE) and 39 un-dissected FFPE tumor specimens from patients treated with gefitinib or erlotinib in whom clinical outcome was available. 173 specimens were independently analyzed by direct sequencing. Results: We detected 48 EGFR mutations by sequencing and 61 using SURVEYOR. All EGFR mutations identified by sequencing, including those using un-dissected tumor specimens, were detected by SURVEYOR and none were missed (sensitivity: 100%, negative predictive value: 100%). 13 mutations were detected by SURVEYOR not detected by sequencing. This included 5 mutations (4 exon 19 deletions; 1 L858R) in 7 (71%) patients who clinically had a PR to gefitinib or erlotinib but who were wild type by sequencing. In 4 patients, 2 with clinical acquired resistance to gefitinib, a T790M mutation was found which was undetected by sequencing. Conclusions: SURVEYOR analysis is a more sensitive method for EGFR mutation detection than direct sequencing. It can be used to detect EGFR mutations from un-dissected tumor specimens and can detect clinically significant activating or resistance associated EGFR mutations not detected by direct sequencing. [Table: see text]
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Nair S, Kuang Y, Pullammanappallil P. Enhanced degradation of waste grass clippings in one and two stage anaerobic systems. ENVIRONMENTAL TECHNOLOGY 2005; 26:1003-11. [PMID: 16196409 DOI: 10.1080/09593332608618488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The present work investigated the use of a simple rumen-fluid-inoculated anaerobic treatment system for the degradation of organic waste. Fresh rumen fluid collected from a fistulated sheep was used as the inoculum and fresh grass clippings were used as the waste material for treatment. Studies were carried out on both a one-stage system where the ligno-cellulosic fraction breaks down into a mixture of soluble products including volatile fatty acids and a two- stage system where these products are subsequently mineralised to biogas. In the one stage system about 70% of the organic waste was solubilized and in the two stage system about 60% waste material was solubilized in a week. About 50% of the degradation was achieved in a 4 day period, showing that a 4 day solids retention time would be a suitable operating regime. The maximum volatile fatty acid production rate was 327 mg COD l(-1) h(-1). A higher loading rate of 30 g l(-1) d(-1) was achieved in these systems compared to anaerobic digesters. Microbiological studies showed an increase in the number of fungal spores as well as a decrease in the number of protozoa in the treatment system. These numbers attained stable values over the duration of the experiments. The system developed is superior to conventional composting or anaerobic digestion and can be applied for the treatment of ligno-cellulosic agricultural residues.
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Niyazov RA, Weinstein LB, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Cetina C, Chen S, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Dashyan N, DeVita R, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CIO, Gothe RW, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Holtrop M, Hu J, Hyde-Wright CE, Ilieva Y, Ingram W, Ito MM, Jenkins D, Joo K, Juengst HG, Kelley JH, Kellie J, Khandaker M, Kim DH, Kim KY, Kim K, Kim MS, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Li J, Livingston K, Lukashin K, Manak JJ, Marchand C, McAleer S, McLauchlan S, McNabb JWC, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Nozar M, O'Rielly GV, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B. Two-nucleon momentum distributions measured in 3He(e,e'pp)n. PHYSICAL REVIEW LETTERS 2004; 92:052303. [PMID: 14995301 DOI: 10.1103/physrevlett.92.052303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Indexed: 05/24/2023]
Abstract
We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic range. The kinetic energy distribution for "fast" nucleons (p>250 MeV/c) peaks where two nucleons each have 20% or less, and the third nucleon has most of the transferred energy. These fast pp and pn pairs are back to back with little momentum along the three-momentum transfer, indicating that they are spectators. Calculations by Sargsian and by Laget also indicate that we have measured distorted two-nucleon momentum distributions by striking one nucleon and detecting the spectator correlated pair.
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Stepanyan S, Hicks K, Carman DS, Pasyuk E, Schumacher RA, Smith ES, Tedeschi DJ, Todor L, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Avakian H, Bagdasaryan H, Ball JP, Barrow SP, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carnahan B, Chen S, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, De Vita R, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Gordon CIO, Gothe R, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ito MM, Jenkins D, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kubarovsky V, Kuhn SE, Kuhn J, Lachniet J, Lawrence D, Li J, Lima A, Livingston K, Lukashin K, Manak JJ, McAleer S, McNabb JWC, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow S, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien J, O'Rielly GV, Opper AK, Osipenko M, Park K, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin P, Sabatié F, Salgado C, Santoro J, Sapunenko V, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith LC, Sober DI, Strakovsky II, Stavinsky A, Stoler P, Suleiman R, Taiuti M, Taylor S, Thoma U, Thompson R, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J. Observation of an exotic S = +1 baryon in exclusive photoproduction from the deuteron. PHYSICAL REVIEW LETTERS 2003; 91:252001. [PMID: 14754107 DOI: 10.1103/physrevlett.91.252001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2003] [Indexed: 05/24/2023]
Abstract
In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups.
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Fatemi R, Skabelin AV, Burkert VD, Crabb D, De Vita R, Kuhn SE, Minehart R, Adams G, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bosted PE, Bouchigny S, Bradford R, Branford D, Brooks WK, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Cetina C, Ciciani L, Clark R, Cole PL, Coleman A, Connelly J, Cords D, Corvisiero P, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Farhi L, Feuerbach RJ, Freyberger A, Ficenec J, Forest TA, Frolov V, Funsten H, Gaff SJ, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CIO, Griffioen KA, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ilieva Y, Ito MM, Jenkins D, Joo K, Keith C, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Koubarovski V, Kramer LH, Kuang Y, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Major W, Manak JJ, Marchand C, McAleer S, McNabb JWC, Mecking BA, Mehrabyan S, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, O'Rielly GV, Osipenko M, Park K, Pasyuk E, Peterson G, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rock SE, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Sargsyan M, Schumacher RA, Seely M, Serov VS, Sharabian YG, Shaw J, Simionatto S, Smith ES, Smith T, Smith LC, Sober DI, Sorrel L, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, Zhou Z. Measurement of the proton spin structure function g1(x,Q2) for Q2 from 0.15 to 1.6 GeV2 with CLAS. PHYSICAL REVIEW LETTERS 2003; 91:222002. [PMID: 14683231 DOI: 10.1103/physrevlett.91.222002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Indexed: 05/24/2023]
Abstract
Double-polarization asymmetries for inclusive ep scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a longitudinally polarized NH3 target in the CLAS detector. The polarized structure function g(1)(x,Q2) was extracted throughout the nucleon resonance region and into the deep inelastic regime, for Q(2)=0.15-1.64 GeV2. The contributions to the first moment Gamma(1)(Q2)= integral g(1)(x,Q2) dx were determined up to Q(2)=1.2 GeV2. Using a parametrization for g(1) in the unmeasured low x regions, the complete first moment was estimated over this Q2 region. A rapid change in Gamma(1) is observed for Q2<1 GeV2, with a sign change near Q(2)=0.3 GeV2, indicating dominant contributions from the resonance region. At Q(2)=1.2 GeV2 our data are below the perturbative QCD evolved scaling value.
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97
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Ripani M, Burkert VD, Mokeev V, Battaglieri M, De Vita R, Golovach E, Taiuti M, Adams G, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Beard K, Bektasoglu M, Bellis M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Calarco JR, Carman DS, Carnahan B, Cazes A, Cetina C, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gaff SJ, Gai M, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ishkhanov B, Ito MM, Jenkins D, Joo K, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JWC, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Opper AK, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Quinn B, Raue BA, Riccardi G, Ricco G, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, Zhou Z. Measurement of ep-->e' ppi+ pi- and baryon resonance analysis. PHYSICAL REVIEW LETTERS 2003; 91:022002. [PMID: 12906472 DOI: 10.1103/physrevlett.91.022002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2002] [Indexed: 05/24/2023]
Abstract
The cross section for the reaction ep-->e(')ppi(+)pi(-) was measured in the resonance region for 1.4<W<2.1 GeV and 0.5<Q2<1.5 GeV(2)/c(2) using the CLAS detector at Jefferson Laboratory. The data show resonant structures not visible in previous experiments. The comparison of our data to a phenomenological prediction using available information on N(*) and Delta states shows an evident discrepancy. A better description of the data is obtained either by a sizable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses.
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98
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Carman DS, Joo K, Mestayer MD, Raue BA, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Armstrong DS, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow SP, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Bennhold C, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carnahan B, Cazes A, Cetina C, Ciciani L, Clark R, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, Degtyarenko PV, Denizli H, Dennis L, DeVita R, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gaff SJ, Gai M, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Golovach E, Gordon CIO, Griffioen K, Grimes S, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ishkhanov B, Ito MM, Jenkins D, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Manak JJ, Marchand C, Mart T, McAleer S, McCarthy J, McNabb JWC, Mecking BA, Mehrabyan S, Melone JJ, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Opper AK, Osipenko M, Park K, Paschke K, Pasyuk E, Peterson G, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin P, Sabatié F, Sabourov K, Salgado C, Santoro J, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, Zhou Z. First measurement of transferred polarization in the exclusive ep-->e'K+Lambda--> reaction. PHYSICAL REVIEW LETTERS 2003; 90:131804. [PMID: 12689277 DOI: 10.1103/physrevlett.90.131804] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2002] [Indexed: 05/24/2023]
Abstract
The first measurements of the transferred polarization for the exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using the CLAS spectrometer. A 2.567 GeV beam was used to measure the hyperon polarization over Q2 from 0.3 to 1.5 (GeV/c)(2), W from 1.6 to 2.15 GeV, and over the full K+ center-of-mass angular range. Comparison with predictions of hadrodynamic models indicates strong sensitivity to the underlying resonance contributions. A nonrelativistic quark-model interpretation of our data suggests that the ssmacr; quark pair is produced with spins predominantly antialigned. Implications for the validity of the most widely used quark-pair creation operator are discussed.
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Battaglieri M, Brunoldi M, De Vita R, Laget JM, Osipenko M, Ripani M, Taiuti M, Adams G, Amaryan MJ, Anciant E, Anghinolfi M, Armstrong DS, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Barrow S, Beard K, Bektasoglu M, Berman BL, Bersani A, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cazes A, Cetina C, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, Degtyarenko PV, Demirchyan R, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Farhi L, Feuerbach RJ, Ficenec J, Forest TA, Freyberger AP, Frolov V, Funsten H, Gaff SJ, Gai M, Garcon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Golovach E, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Joo K, Kelley JH, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Lachniet J, Lawrence D, Lucas M, Lukashin K, Major RW, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JWC, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Morrow S, Mozer MU, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nelson SO, Niccolai S, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, Opper AK, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Preedom BM, Price JW, Protopopescu D, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabourov K, Salgado C, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Taylor S, Tedeschi DJ, Todor L, Thoma U, Thompson R, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood M, Yegneswaran A, Yun J, Zhang B, Zhao J, Zhou Z. Photoproduction of the omega meson on the proton at large momentum transfer. PHYSICAL REVIEW LETTERS 2003; 90:022002. [PMID: 12570539 DOI: 10.1103/physrevlett.90.022002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2002] [Indexed: 05/24/2023]
Abstract
The differential cross section, dsigma/dt, for omega meson exclusive photoproduction on the proton above the resonance region (2.6<W<2.9 GeV) was measured up to a momentum transfer -t=5 GeV2 using the CLAS detector at Jefferson Laboratory. The omega channel was identified by detecting a proton and pi(+) in the final state and using the missing mass technique. While the low momentum transfer region shows the typical diffractive pattern expected from Pomeron and Reggeon exchange, at large -t the differential cross section has a flat behavior. This feature can be explained by introducing quark interchange processes in addition to the QCD-inspired two-gluon exchange.
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100
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Kuang Y, Lepesteur M, Pullammanappallil P, Ho GE. Influence of co-substrates on structure of microbial aggregates in long-chain fatty acid-fed anaerobic digesters. Lett Appl Microbiol 2002; 35:190-4. [PMID: 12180939 DOI: 10.1046/j.1472-765x.2002.01163.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS The purpose of this study was to investigate the influence of co-substrates, such as glucose and cysteine, on the structure of microbial aggregates in anaerobic digesters treating oleate, a long-chain fatty acid (LCFA). METHODS AND RESULTS Transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM) were used to examine the structure of microbial aggregates. Fluorescence in situ hybridization (FISH) techniques were also used to characterize and localize the different trophic groups present in the aggregates. Oleate was found to inhibit the methanogenic activity and formation of granular biomass in digesters. The addition of co-substrates, such as glucose and cysteine either singly or in combination, increased the methanogenic activity and formation of granular biomass. Glucose was more effective than cysteine in reducing the inhibition by oleate on the methanogenic bacteria and in enhancing the formation of granules. CONCLUSIONS The addition of nutrient substrate, such as glucose and cysteine could decrease the toxicity of LCFA on anaerobic granulation. SIGNIFICANCE AND IMPACT OF THE STUDY The results suggest that the addition of other substrates might decrease the toxicity of LCFA on the granulation of biomass in anaerobic digesters and enhance methanogenic activity. A combination of TEM, CLSM and FISH techniques provides a better tool for visualizing microbial aggregates and for differentiating and localizing different microbial groups within these aggregates.
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