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Sample records for 910-kda class-2 pepc

  1. Bacterial-type Phosphoenolpyruvate Carboxylase (PEPC) Functions as a Catalytic and Regulatory Subunit of the Novel Class-2 PEPC Complex of Vascular Plants*

    PubMed Central

    O'Leary, Brendan; Rao, Srinath K.; Kim, Julia; Plaxton, William C.

    2009-01-01

    Phosphoenolpyruvate carboxylase (PEPC) is a tightly regulated anaplerotic enzyme situated at a major branch point of the plant C metabolism. Two distinct oligomeric classes of PEPC occur in the triglyceride-rich endosperm of developing castor oil seeds (COS). Class-1 PEPC is a typical homotetramer composed of identical 107-kDa plant-type PEPC (PTPC) subunits (encoded by RcPpc3), whereas the novel Class-2 PEPC 910-kDa hetero-octameric complex arises from a tight interaction between Class-1 PEPC and distantly related 118-kDa bacterial-type PEPC (BTPC) polypeptides (encoded by RcPpc4). Here, COS BTPC was expressed from full-length RcPpc4 cDNA in Escherichia coli as an active PEPC that exhibited unusual properties relative to PTPCs, including a tendency to form large aggregates, enhanced thermal stability, a high Km(PEP), and insensitivity to metabolite effectors. A chimeric 900-kDa Class-2 PEPC hetero-octamer having a 1:1 stoichiometry of BTPC:PTPC subunits was isolated from a mixture of clarified extracts containing recombinant RcPPC4 and an Arabidopsis thaliana Class-1 PEPC (the PTPC, AtPPC3). The purified Class-2 PEPC exhibited biphasic PEP saturation kinetics with high and low affinity sites attributed to its AtPPC3 and RcPPC4 subunits, respectively. The RcPPC4 subunits: (i) catalyzed the majority of the Class-2 PEPC Vmax, particularly in the presence of the inhibitor l-malate, and (ii) also functioned as Class-2 PEPC regulatory subunits by modulating PEP binding and catalytic potential of its AtPPC3 subunits. BTPCs appear to associate with PTPCs to form stable Class-2 PEPC complexes in vivo that are hypothesized to maintain high flux from PEP under physiological conditions that would otherwise inhibit Class-1 PEPCs. PMID:19605358

  2. Bacterial-type phosphoenolpyruvate carboxylase (PEPC) functions as a catalytic and regulatory subunit of the novel class-2 PEPC complex of vascular plants.

    PubMed

    O'Leary, Brendan; Rao, Srinath K; Kim, Julia; Plaxton, William C

    2009-09-11

    Phosphoenolpyruvate carboxylase (PEPC) is a tightly regulated anaplerotic enzyme situated at a major branch point of the plant C metabolism. Two distinct oligomeric classes of PEPC occur in the triglyceride-rich endosperm of developing castor oil seeds (COS). Class-1 PEPC is a typical homotetramer composed of identical 107-kDa plant-type PEPC (PTPC) subunits (encoded by RcPpc3), whereas the novel Class-2 PEPC 910-kDa hetero-octameric complex arises from a tight interaction between Class-1 PEPC and distantly related 118-kDa bacterial-type PEPC (BTPC) polypeptides (encoded by RcPpc4). Here, COS BTPC was expressed from full-length RcPpc4 cDNA in Escherichia coli as an active PEPC that exhibited unusual properties relative to PTPCs, including a tendency to form large aggregates, enhanced thermal stability, a high K(m)((PEP)), and insensitivity to metabolite effectors. A chimeric 900-kDa Class-2 PEPC hetero-octamer having a 1:1 stoichiometry of BTPC:PTPC subunits was isolated from a mixture of clarified extracts containing recombinant RcPPC4 and an Arabidopsis thaliana Class-1 PEPC (the PTPC, AtPPC3). The purified Class-2 PEPC exhibited biphasic PEP saturation kinetics with high and low affinity sites attributed to its AtPPC3 and RcPPC4 subunits, respectively. The RcPPC4 subunits: (i) catalyzed the majority of the Class-2 PEPC V(max), particularly in the presence of the inhibitor l-malate, and (ii) also functioned as Class-2 PEPC regulatory subunits by modulating PEP binding and catalytic potential of its AtPPC3 subunits. BTPCs appear to associate with PTPCs to form stable Class-2 PEPC complexes in vivo that are hypothesized to maintain high flux from PEP under physiological conditions that would otherwise inhibit Class-1 PEPCs.

  3. PEPC LRU: Ball Support Assembly

    SciTech Connect

    Alger, T

    1999-05-14

    The PEPC LRU upper ball support assembly consists of a ball and a pneumatic air cylinder/conical seat latching mechanism to be attached to the optics support frame,and a ball attached to the PEPC LRU. Both components are designed to allow manual positioning in three axes. Upon insertion of the PEPC LRU into the structure, the upper pneumatic cylinder is actuated to latch the two assemblies together through the conical seat device to grab the lower ball to support the LRU weight. To be conservative, the design load for the assembly is 1500 pounds (the prototype PEPC LRU weight was measured to be near 1380 pounds).

  4. The impact of PEPC phosphorylation on growth and development of Arabidopsis thaliana: molecular and physiological characterization of PEPC kinase mutants.

    PubMed

    Meimoun, Patrice; Gousset-Dupont, Aurélie; Lebouteiller, Bénédicte; Ambard-Bretteville, Françoise; Besin, Evelyne; Lelarge, Caroline; Mauve, Caroline; Hodges, Michael; Vidal, Jean

    2009-05-19

    Two phosphoenolpyruvate carboxylase (PEPC) kinase genes (PPCk1 and PPCk2) are present in the Arabidopsis genome; only PPCk1 is expressed in rosette leaves. Homozygous lines of two independent PPCk1 T-DNA-insertional mutants showed very little (dln1), or no (csi8) light-induced PEPC phosphorylation and a clear retard in growth under our greenhouse conditions. A mass-spectrometry-based analysis revealed significant changes in metabolite profiles. However, the anaplerotic pathway initiated by PEPC was only moderately altered. These data establish the PPCk1 gene product as responsible for leaf PEPC phosphorylation in planta and show that the absence of PEPC phosphorylation has pleiotropic consequences on plant metabolism.

  5. Hydrogen peroxide regulated photosynthesis in C4-pepc transgenic rice.

    PubMed

    Ren, C G; Li, X; Liu, X L; Wei, X D; Dai, C C

    2014-01-01

    In this study, we investigated the photosynthetic physiological basis in 'PC' transgenic rice (Oryza sativa L.), showing high-level expression of the gene encoding C4 phosphoenolpyruvate carboxylase (pepc), by hydrogen peroxide (H2O2). The C4-PEPC gene (pepc) from maize in the transgenic rice plants was checked by PCR. Comparison of yield components and photosynthetic indices between PC and untransformed wild-type (WT) plants indicated that increased yield in PC was associated with higher net photosynthetic rate and higher activities of phosphoenolpyruvate carboxylase (PEPC). Both PC and WT plants were treated with 1 mmol L(-1) abscisic acid (ABA), 0.04% 1-butanol (BA), 2 mmol L(-1) neomycin (NS), or 2 mmol L(-1) diphenyleneiodonium chloride (DPI) to investigate the relationship between photosynthesis and levels of H2O2 and phosphatidic acid. In both PC and WT, ABA induced H2O2 generation and simultaneous decrease in stomatal conductance (g(s)). PC plants treated with BA showed decreased H2O2 content and strongly increased g(s) within 2 h of treatment. Similar results were observed in response to DPI treatment in PC. However, WT did not observe the decrease of H2O2 during the treatments of BA and DPI. The reduced H2O2 content in PC caused by BA treatment differed to that induced by DPI because BA did not inhibit NADPH oxidase activities. While BA induced a larger PEPC activity in PC, and higher catalase activity as well. These results indicated that the regulation of endogenous H2O2 metabolism of PC could be helpful for enhancing photosynthetic capability.

  6. Evolutionary history of PEPC genes in green plants: Implications for the evolution of CAM in orchids.

    PubMed

    Deng, Hua; Zhang, Liang-Sheng; Zhang, Guo-Qiang; Zheng, Bao-Qiang; Liu, Zhong-Jian; Wang, Yan

    2016-01-01

    The phosphoenolpyruvate carboxylase (PEPC) gene is the key enzyme in CAM and C4 photosynthesis. A detailed phylogenetic analysis of the PEPC family was performed using sequences from 60 available published plant genomes, the Phalaenopsis equestris genome and RNA-Seq of 15 additional orchid species. The PEPC family consists of three distinct subfamilies, PPC-1, PPC-2, and PPC-3, all of which share a recent common ancestor in chlorophyte algae. The eudicot PPC-1 lineage separated into two clades due to whole genome duplication (WGD). Similarly, the monocot PPC-1 lineage also divided into PPC-1M1 and PPC-1M2 through an ancient duplication event. The monocot CAM- or C4-related PEPC originated from the clade PPC-1M1. WGD may not be the major driver for the performance of CAM function by PEPC, although it increased the number of copies of the PEPC gene. CAM may have evolved early in monocots, as the CAM-related PEPC of orchids originated from the monocot ancient duplication, and the earliest CAM-related PEPC may have evolved immediately after the diversification of monocots, with CAM developing prior to C4. Our results represent the most complete evolutionary history of PEPC genes in green plants to date and particularly elucidate the origin of PEPC in orchids.

  7. Light-regulated and cell-specific methylation of the maize PEPC promoter

    PubMed Central

    Tolley, Ben J.; Woodfield, Helen; Wanchana, Samart; Bruskiewich, Richard; Hibberd, Julian M.

    2012-01-01

    The molecular mechanisms governing PEPC expression in maize remain to be fully defined. Differential methylation of a region in the PEPC promoter has been shown to correlate with transcript accumulation, however, to date, investigations into the role of DNA methylation in maize PEPC expression have relied on the use of methylation-sensitive restriction enzymes. Bisulphite sequencing was used here to provide a single-base resolution methylation map of the maize PEPC promoter. It is shown that four cytosine residues in the PEPC promoter are heavily methylated in maize root tissue. In leaves, de-methylation of these cytosines is dependent on illumination and is coincident with elevated PEPC expression. Furthermore, light-regulated de-methylation of these cytosines occurs only in mesophyll cells. No methylation was discovered in the 0.6 kb promoter required for mesophyll-specific expression indicating that cytosine methylation is not required to direct the cell-specificity of PEPC expression. This raises interesting questions regarding the function of the cell-specific cytosine de-methylation observed in the upstream region of the PEPC promoter. PMID:22143916

  8. Cloning of PEPC-1 from a C4 halophyte Suaeda aralocaspica without Kranz anatomy and its recombinant enzymatic activity in responses to abiotic stresses.

    PubMed

    Cheng, Gang; Wang, Lu; Lan, Haiyan

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) is a key enzyme of C4 photosynthetic pathway and plays an important biochemical role in higher plants and micro organisms. To gain understanding of the role of PEPC in stress adaptation in plant, we cloned PEPC gene from Suaeda aralocaspica, a C4 species without Kranz anatomy, and performed a series of experiments with PEPC gene expressed in Escherichia coli under various abiotic stresses. Results showed that, based on the homology cloning and 5'-RACE technique, the full-length cDNA sequence of PEPC (2901 bp) from S. aralocaspica was obtained, which shares the typical conserved domains to documented PEPCs and was identified as PEPC-1 in accord to the reported partial sequence (ppc-1) in S. aralocaspica. qRT-PCR analysis revealed the expression patterns of PEPC-1 and PEPC-2 (known as ppc-2, another plant type of PEPC) in S. aralocaspica, suggesting that PEPC-1 was up-regulated during seed germination and under NaCl stress, and presented higher level in chlorenchyma than other tissues, which were significantly different with PEPC-2. Afterwards, PEPC-1 was recombinant in E. coli (pET-28a-PEPC) and expressed as an approximate 110 kDa protein. Under various abiotic stresses, the recombinant E. coli strain harboring with PEPC-1 showed significant advantage in growth at 400-800 mmol L(-1) NaCl, 10-20% PEG6000, 25 and 30 °C lower temperature, 50-200 μmol L(-1) methyl viologen, and pH 5.0 and 9.0 condition, compared to control. Further analysis of the enzymatic characteristics of the recombinant PEPC-1 suggests that it was the higher enzyme activity of PEPC-1 which might confer the stress tolerance to E. coli. We speculate that over expression of PEPC-1 is probably related to regulation of oxaloacetate (OAA) in tricarboxylic acid (TCA) cycle in E. coli, which may contribute to further understanding of the physiological function of PEPC in S. aralocaspica.

  9. Expression and knockdown of the PEPC1 gene affect carbon flux in the biosynthesis of triacylglycerols by the green alga Chlamydomonas reinhardtii.

    PubMed

    Deng, Xiaodong; Cai, Jiajia; Li, Yajun; Fei, Xiaowen

    2014-11-01

    The regulation of lipid biosynthesis is important in photosynthetic eukaryotic cells. This regulation is facilitated by the direct synthesis of fatty acids and triacylglycerol (TAG), and by other controls of the main carbon metabolic pathway. In this study, knockdown of the mRNA expression of the Chlamydomonas phosphoenolpyruvate carboxylase isoform 1 (CrPEPC1) gene by RNA interference increased TAG level by 20 % but decreased PEPC activities in the corresponding transgenic algae by 39-50 %. The decrease in CrPEPC1 expression increased the expression of TAG biosynthesis-related genes, such as acyl-CoA:diacylglycerol acyltransferase and phosphatidate phosphatase. Conversely, CrPEPC1 over-expression decreased TAG level by 37 % and increased PEPC activities by 157-184 %. These observations suggest that the lipid content of algal cells can be controlled by regulating the CrPEPC1 gene.

  10. Cryptococcal osteomyelitis and meningitis in a patient with non-hodgkin's lymphoma treated with PEP-C.

    PubMed

    To, Christina A; Hsieh, Robert W; McClellan, James Scott; Howard, Walter; Fischbein, Nancy J; Brown, Janice M Y; Felsher, Dean W; Fan, Alice C

    2012-09-07

    The authors present the first case report of a patient with lymphoma who developed disseminated cryptococcal osteomyelitis and meningitis while being treated with the PEP-C (prednisone, etoposide, procarbazine and cyclophosphamide) chemotherapy regimen. During investigation of fever and new bony lesions, fungal culture from a rib biopsy revealed that the patient had cryptococcal osteomyelitis. Further evaluation demonstrated concurrent cryptococcal meningitis. The patient's disseminated cryptococcal infections completely resolved after a full course of antifungal treatment. Cryptococcal osteomyelitis is itself an extremely rare diagnosis, and the unique presentation with concurrent cryptococcal meningitis in our patient with lymphoma was likely due to his PEP-C treatment. It is well recognised that prolonged intensive chemotherapeutic regimens place patients at risk for atypical infections; yet physicians should recognise that even chronic low-dose therapies can put patients at risk for fungal infections. Physicians should consider fungal infections as part of the infectious investigation of a lymphopaenic patient on PEP-C.

  11. Cryptococcal osteomyelitis and meningitis in a patient with non-hodgkin’s lymphoma treated with PEP-C

    PubMed Central

    To, Christina A; Hsieh, Robert W; McClellan, James Scott; Howard, Walter; Fischbein, Nancy J; Brown, Janice M Y; Felsher, Dean W; Fan, Alice C

    2012-01-01

    The authors present the first case report of a patient with lymphoma who developed disseminated cryptococcal osteomyelitis and meningitis while being treated with the PEP-C (prednisone, etoposide, procarbazine and cyclophosphamide) chemotherapy regimen. During investigation of fever and new bony lesions, fungal culture from a rib biopsy revealed that the patient had cryptococcal osteomyelitis. Further evaluation demonstrated concurrent cryptococcal meningitis. The patient’s disseminated cryptococcal infections completely resolved after a full course of antifungal treatment. Cryptococcal osteomyelitis is itself an extremely rare diagnosis, and the unique presentation with concurrent cryptococcal meningitis in our patient with lymphoma was likely due to his PEP-C treatment. It is well recognised that prolonged intensive chemotherapeutic regimens place patients at risk for atypical infections; yet physicians should recognise that even chronic low-dose therapies can put patients at risk for fungal infections. Physicians should consider fungal infections as part of the infectious investigation of a lymphopaenic patient on PEP-C. PMID:22962380

  12. Phosphoenolpyruvate carboxylase regulation in C4-PEPC-expressing transgenic rice during early responses to drought stress.

    PubMed

    Liu, Xiaolong; Li, Xia; Zhang, Chen; Dai, Chuanchao; Zhou, Jiayu; Ren, Chenggang; Zhang, Jinfei

    2017-02-01

    Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) has important functions in C4 photosynthesis and biosynthesis of intermediate metabolites. In this study, the drought resistance of C4-PEPC-expressing transgenic rice (Oryza sativa, line PC) plants was assessed using simulated drought conditions [i.e. polyethylene glycol (PEG)-6000 treatment]. The dry weight of PC plants was higher than that of wild-type (WT) plants following treatment with 15% PEG-6000 for 16 days. Furthermore, the water use efficiency, relative water content and proline content in PC plants were higher than those of WT plants, as were C4-PEPC activity and transcript levels following treatment with 5% PEG-6000 for 2 h. The protein kinase activities and transcript levels of sucrose non-fermenting-1-related protein kinases (SnRKs) genes, such as SnRK1a, OsK24 and OsK35 were also higher in PC plants than in WT plants following treatment with 5% PEG-6000 for 2 h. Additionally, phosphoenolpyruvate carboxylase kinase (PPCK, EC 4.1.1.32) activities and transcript levels (e.g. PPCK1 and PPCK2) increased following drought treatment. These changes were regulated by signaling molecules, such as calcium, nitric oxide and hydrogen peroxide. Furthermore, the -1095 to -416 region of the C4-PEPC promoter in PC plants was demethylated following exposure to drought conditions for 1 h. The demethylation coincided with an increase in C4-PEPC expression. Our data suggest that the demethylation of the C4-PEPC promoter and the phosphorylation catalyzed by PPCK have key roles in conferring drought tolerance to the transgenic rice plants.

  13. Investigation of Class 2b Trucks

    SciTech Connect

    Davis, S.C.

    2002-04-03

    The popularity of trucks in the class 2 category--that is, those with a 6,000 to 10,000 pounds (lbs) gross vehicle weight rating (GVWR)--has increased since the late 1970s/early 1980s. The purpose of this research is to identify and examine vehicles in the upper portion of the class 2 weight range (designated as vehicle class 2b) and to assess their impact. Vehicles in class 2b (8,500-10,000 lbs GVWR) include pickup trucks, sport utility vehicles (SUVs), and large vans (i.e., not minivans). Oak Ridge National Laboratory researched each individual truck model to determine which models were class 2b trucks and arrived at four methodologies to derive sales volumes. Two methods--one for calendar year and one for model year sales--were recommended for producing believable and reliable results. The study indicates that 521,000 class 2b trucks were sold in calendar year 1999--6.4% of sales of all trucks under 10,000 lbs. Eighty-two percent of class 2b trucks sold in 1999 were pickups; one third of class 2b trucks sold in 1999 were diesel. There were 5.8 million class 2b trucks on the road in 2000, which amounts to 7.8% of all trucks under 10,000 lbs. Twenty-four percent of the class 2b truck population is diesel. Estimates show that class 2b trucks account for 8% of annual miles traveled by trucks under 10,000 lbs and 9% of fuel use. Data on class 2b trucks are scarce. As the Tier 2 standards, which apply to passenger vehicles in the 8,500-10,000 lb GVWR category, become effective, additional data on class 2b trucks may become available--not only emissions data, but data in all areas. At the moment, distinguishing class 2b trucks from class 2 trucks in general is a substantial task requiring data on an individual model level.

  14. Durable Responses with the Metronomic Regimen RT-PEPC in Elderly Patients with Recurrent Mantle Cell Lymphoma

    PubMed Central

    Ruan, Jia; Martin, Peter; Coleman, Morton; Furman, Richard R.; Cheung, Ken; Faye, Adam; Elstrom, Rebecca; Lachs, Mark; Hajjar, Katherine A.; Leonard, John P.

    2010-01-01

    BACKGROUND Targeting the tumor microenvironment and angiogenesis is a novel lymphoma therapeutic strategy. We report safety, activity and angiogenic profiling with the RT-PEPC regimen (rituximab with thalidomide, and prednisone, etoposide, procarbazine and cyclophosphamide) in recurrent mantle cell lymphoma (MCL). METHODS RT-PEPC includes induction (months 1–3) of weekly rituximab × 4, daily thalidomide (50 mg) and PEPC, then maintenance thalidomide (100 mg), oral PEPC titrated to neutrophil count, and rituximab every 4 months. Endpoints included safety, efficacy, quality of life (QoL), and translational studies including tumor angiogenic phenotyping, plasma VEGF and circulating endothelial cells. RESULTS Twenty-five pts were enrolled (22 evaluable) with median age 68 yrs (range 52–81), 24 (96%) stage III/IV, 18 (72%) IPI 3–5, 20 (80%) high risk MIPI, median 2 prior therapies (range 1–7), and 15 (60%) bortezomib progressors. At a median follow-up of 38 months, ORR was 73% (32% CR/CRu, 41% PR, n=22) and median PFS 10 months. Four CRs are ongoing (6+, 31+, 48+ and 50+ months). Toxicities included grade 1–2 fatigue, rash, neuropathy and cytopenias including grade 1–2 thrombocytopenia (64%) and grade 3–4 neutropenia (64%). Two thromboses and 5 grade 3–4 infections occurred. QoL was maintained or improved. Correlative studies demonstrated tumor autocrine angiogenic loop (expression of VEGFA and VEGFR1) and heightened angiogenesis and lymphangiogenesis in stroma. Plasma VEGF and circulating endothelial cells trended down with treatment. CONCLUSIONS RT-PEPC has significant and durable activity in MCL, with manageable toxicity and maintained QoL. Novel low-intensity approaches warrant further evaluation, potentially as initial therapy in elderly patients. PMID:20235190

  15. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  16. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  17. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  18. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  19. 49 CFR 174.201 - Class 2 (gases) material cylinders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Class 2 (gases) material cylinders. 174.201... RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.201 Class 2 (gases) material cylinders. (a) Except as provided in paragraphs (b) and (c) of this section, cylinders containing Class 2...

  20. Physiological characteristics and metabolomics of transgenic wheat containing the maize C4 phosphoenolpyruvate carboxylase (PEPC) gene under high temperature stress.

    PubMed

    Qi, Xueli; Xu, Weigang; Zhang, Jianzhou; Guo, Rui; Zhao, Mingzhong; Hu, Lin; Wang, Huiwei; Dong, Haibin; Li, Yan

    2017-03-01

    In this paper, two transgenic wheat lines, PC27 and PC51, containing the maize PEPC gene and its wild-type (WT) were used as experimental material to study the effects of high temperature on their photosynthetic physiological characteristics and metabolome. The results showed that transgenic wheat lines had higher photosynthetic rate (P n) than WT under non-stress treatment (NT) and high temperature stress treatment (HT), and more significantly under HT. The change trends of F v/F m, Ф PSII, and q P were similar to P n, whereas that of non-photochemical quenching (NPQ) was the opposite. Compared with WT, no differences in chlorophyll content between the transgenic wheat and WT were observed under NT, but two transgenic lines had relatively higher contents than WT under HT. The change trends of Chlorophyll a/b radio, the decreased values of F m, Wk, and Vj, and the activity of the antioxidant enzyme were consistent with the chlorophyll content. Compared with WT, transgenic wheat lines exhibited lower rate of superoxide anion production, H2O2 and malondialdehyde content under HT, and no significant differences were observed under NT. The expression pattern of the ZmPEPC gene and wheat endogenous photosynthesis-related genes were in agreement with that of P n. Compared with WT, about 13 different metabolites including one organic acid, six amino acids, four sugars, and two polyols were identified under NT; 25 different metabolites including six organic acids, 12 amino acids, four sugars, and three polyols were identified under HT. Collectively, our results indicate that ZmPEPC gene can enhance photochemical and antioxidant enzyme activity, upregulate the expression of photosynthesis-related genes, delay degradation of chlorophyll, change contents of proline and other metabolites in wheat, and ultimately improves its heat tolerance.

  1. Technology and optical characterization of luminophore coordination compounds Eu(o-MBA)3Phen and NC PEPC/Eu(o-MBA)3Phen

    NASA Astrophysics Data System (ADS)

    Bordian, Olga; Verlan, Victor; Culeac, Ion; Iovu, Mihail; Zubareva, Vera

    2016-12-01

    Were obtained a new nanocomposite (NC) based on poly N-epoxy prolyl carbazol (PEPC) and the coordination compound luminophore Eu(o-MBA)3Phen, where o-MBA is o- methylbenzoic acid and Phen - phenanthroline. Nanocrystals of Eu(o-MBA)3Phen with the dimensions 50 nm were uniformly incorporated into the PEPC polymer matrix with various concentrations. The absorption spectra of coordination compounds and thin layers of NC PEPC/Eu(o-MBA)3Phen revealed 1 intensive absorption bands at 2.02 eV. Photoluminescence (PL) spectra showed an intense red luminescence at 578 - 699 nm, which is assigned to the transitions 4D0->7Fi (i= 0,1,2 3 4) in the 4f-shell of the Eu3+ ion.

  2. Pyramiding expression of maize genes encoding phosphoenolpyruvate carboxylase (PEPC) and pyruvate orthophosphate dikinase (PPDK) synergistically improve the photosynthetic characteristics of transgenic wheat.

    PubMed

    Zhang, HuiFang; Xu, WeiGang; Wang, HuiWei; Hu, Lin; Li, Yan; Qi, XueLi; Zhang, Lei; Li, ChunXin; Hua, Xia

    2014-09-01

    Using particle bombardment transformation, we introduced maize pepc cDNA encoding phosphoenolpyruvate carboxylase (PEPC) and ppdk cDNA encoding pyruvate orthophosphate dikinase (PPDK) into the C3 crop wheat to generate transgenic wheat lines carrying cDNA of pepc (PC lines), ppdk (PK lines) or both (PKC lines). The integration, transcription, and expression of the foreign genes were confirmed by Southern blot, Real-time quantitative reverse transcription PCR (Q-RT-PCR), and Western blot analysis. Q-RT-PCR results indicated that the average relative expression levels of pepc and ppdk in the PKC lines reached 10 and 4.6, respectively, compared to their expressions in untransformed plants (set to 1). The enzyme activities of PEPC and PPDK in the PKC lines were 4.3- and 2.1-fold higher, respectively, than in the untransformed control. The maximum daily net photosynthetic rates of the PKC, PC, and PK lines were enhanced by 26.4, 13.3, and 4.5%, respectively, whereas the diurnal accumulations of photosynthesis were 21.3, 13.9, and 6.9%, respectively, higher than in the control. The Fv/Fm of the transgenic plants decreased less than in the control under high temperature and high light conditions (2 weeks after anthesis), suggesting that the transgenic wheat transports more absorbed light energy into a photochemical reaction. The exogenous maize C4-specific pepc gene was more effective than ppdk at improving the photosynthetic performance and yield characteristics of transgenic wheat, while the two genes showed a synergistic effect when they were transformed into the same genetic background, because the PKC lines exhibited improved photosynthetic and physiological traits.

  3. 46 CFR 170.260 - Class 2 doors; permissible locations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Class 2 doors; permissible locations. 170.260 Section... STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Watertight Bulkhead Doors § 170.260 Class 2 doors; permissible locations. (a) Except as provided in paragraphs (b) and (c) of this section, a Class 2 door...

  4. 46 CFR 170.260 - Class 2 doors; permissible locations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Class 2 doors; permissible locations. 170.260 Section... STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Watertight Bulkhead Doors § 170.260 Class 2 doors; permissible locations. (a) Except as provided in paragraphs (b) and (c) of this section, a Class 2 door...

  5. Kranz and single-cell forms of C4 plants in the subfamily Suaedoideae show kinetic C4 convergence for PEPC and Rubisco with divergent amino acid substitutions

    PubMed Central

    Rosnow, Josh J.; Evans, Marc A.; Kapralov, Maxim V.; Cousins, Asaph B.; Edwards, Gerald E.; Roalson, Eric H.

    2015-01-01

    The two carboxylation reactions performed by phosphoenolpyruvate carboxylase (PEPC) and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) are vital in the fixation of inorganic carbon for C4 plants. The abundance of PEPC is substantially elevated in C4 leaves, while the location of Rubisco is restricted to one of two chloroplast types. These differences compared with C3 leaves have been shown to result in convergent enzyme optimization in some C4 species. Investigation into the kinetic properties of PEPC and Rubisco from Kranz C4, single cell C4, and C3 species in Chenopodiaceae s. s. subfamily Suaedoideae showed that these major carboxylases in C4 Suaedoideae species lack the same mutations found in other C4 systems which have been examined; but still have similar convergent kinetic properties. Positive selection analysis on the N-terminus of PEPC identified residues 364 and 368 to be under positive selection with a posterior probability >0.99 using Bayes empirical Bayes. Compared with previous analyses on other C4 species, PEPC from C4 Suaedoideae species have different convergent amino acids that result in a higher K m for PEP and malate tolerance compared with C3 species. Kinetic analysis of Rubisco showed that C4 species have a higher catalytic efficiency of Rubisco (k catc in mol CO2 mol–1 Rubisco active sites s–1), despite lacking convergent substitutions in the rbcL gene. The importance of kinetic changes to the two-carboxylation reactions in C4 leaves related to amino acid selection is discussed. PMID:26417023

  6. Diversity and evolution of class 2 CRISPR-Cas systems.

    PubMed

    Shmakov, Sergey; Smargon, Aaron; Scott, David; Cox, David; Pyzocha, Neena; Yan, Winston; Abudayyeh, Omar O; Gootenberg, Jonathan S; Makarova, Kira S; Wolf, Yuri I; Severinov, Konstantin; Zhang, Feng; Koonin, Eugene V

    2017-03-01

    Class 2 CRISPR-Cas systems are characterized by effector modules that consist of a single multidomain protein, such as Cas9 or Cpf1. We designed a computational pipeline for the discovery of novel class 2 variants and used it to identify six new CRISPR-Cas subtypes. The diverse properties of these new systems provide potential for the development of versatile tools for genome editing and regulation. In this Analysis article, we present a comprehensive census of class 2 types and class 2 subtypes in complete and draft bacterial and archaeal genomes, outline evolutionary scenarios for the independent origin of different class 2 CRISPR-Cas systems from mobile genetic elements, and propose an amended classification and nomenclature of CRISPR-Cas.

  7. Green-tissue-specific, C(4)-PEPC-promoter-driven expression of Cry1Ab makes transgenic potato plants resistant to tuber moth (Phthorimaea operculella, Zeller).

    PubMed

    Ghasimi Hagh, Ziba; Rahnama, Hassan; Panahandeh, Jaber; Baghban Kohneh Rouz, Bahram; Arab Jafari, Khoda Morad; Mahna, Nasser; Mahna, Naser

    2009-12-01

    An important strategy for obtaining a safer transgenic plant may be the use of a spatial- or tissue-specific promoter, instead of a constitutive one. In this study, we have used a light-inducible maize PEPC promoter to regulate the cry1Ab gene, aiming to produce transgenic potatoes that are resistant to potato tuber moth (PTM) (Phthorimaea operculella, Zeller). Out of 60 regenerated lines having normal phenotypes, 55 lines were PCR-positive for both the cry1Ab and nptII genes. Southern analysis on three selected putative transgenic lines revealed that they have only a single intact copy of the cry1Ab gene. An investigation of the Cry1Ab protein in the leaves and light-exposed (LE) tubers of the transgenic lines demonstrated the presence of the protein in the foliage and green tubers but not in the light-not exposed (LNE) tubers. A bioassay analysis of excised leaves of nine randomly selected lines showed that eight lines had 100% PTM larval mortality. Confirming results were obtained in six selected lines using the whole plant bioassay in the greenhouse. LE transgenic tubers also exhibited 100% larval mortality; however, the levels of damage to the LNE transgenic tubers were high and statistically the same as those incurred by the non-transgenic ones. Based on the results, we believe that this spatial expression of Cry1Ab using the light-inducible PEPC promoter can control PTM infestation in the field and significantly reduce pollution transmission to storage potatoes.

  8. Class 2 design update for the family of commuter airplanes

    NASA Technical Reports Server (NTRS)

    Creighton, Thomas R.; Hendrich, Louis J.

    1987-01-01

    This is the final report of seven on the design of a family of commuter airplanes. This design effort was performed in fulfillment of NASA/USRA grant NGT-8001. Its contents are as follows: (1) the class 1 baseline designs for the commuter airplane family; (2) a study of takeoff weight penalties imposed on the commuter family due to implementing commonality objectives; (3) component structural designs common to the commuter family; (4) details of the acquisition and operating economics of the commuter family, i.e., savings due to production commonality and handling qualities commonality are determined; (5) discussion of the selection of an advanced turboprop propulsion system for the family of commuter airplanes, and (6) a proposed design for an SSSA controller design to achieve similar handling for all airplanes. Final class 2 commuter airplane designs are also presented.

  9. Gas production from oceanic Class 2 hydrate accumulations

    SciTech Connect

    Moridis, G.J.; Reagan, M.T.

    2007-02-01

    Gas hydrates are solid crystalline compounds in which gasmolecules are lodged within the lattices of ice crystals. The vastamounts of hydrocarbon gases that are trapped in hydrate deposits in thepermafrost and in deep ocean sediments may constitute a promising energysource. Class 2 hydrate deposits are characterized by a Hydrate-BearingLayer (HBL) that is underlain by a saturated zone of mobile water. Inthis study we investigated three methods of gas production via verticalwell designs. A long perforated interval (covering the hydrate layer andextending into the underlying water zone) yields the highest gasproduction rates (up to 20 MMSCFD), but is not recommended for long-termproduction because of severe flow blockage caused by secondary hydrateand ice. A short perforated interval entirely within the water zoneallows long-term production, but only at rates of 4.5 7 MMSCFD. A newwell design involving localized heating appears to be the most promising,alleviating possible blockage by secondary hydrate and/or ice near thewellbore) and delivering sustainably large, long-term rates (10-15MMSCFD).The production strategy involves a cyclical process. During eachcycle, gas production continuously increases, while the correspondingwater production continuously decreases. Each cycle is concluded by acavitation event (marked by a precipitous pressure drop at the well),brought about by the inability of thesystem to satisfy the constant massproduction rate QM imposed at the well. This is caused by the increasinggas contribution to the production stream, and/or flow inhibition causedby secondary hydrate and/or ice. In the latter case, short-term thermalstimulation removes the blockage. The results show that gas productionincreases (and the corresponding water-to-gas ratio RWGC decreases) withan increasing(a) QM, (b) hydrate temperature (which defines its stabilityfor a given pressure), and (c) intrinsic permeability. Lower initialhydrate saturations lead initially to higher gas

  10. Topologies, structures and parameter files for lipid simulations in GROMACS with the OPLS-aa force field: DPPC, POPC, DOPC, PEPC, and cholesterol.

    PubMed

    Kulig, Waldemar; Pasenkiewicz-Gierula, Marta; Róg, Tomasz

    2015-12-01

    In this data article we provide topologies and force field parameters files for molecular dynamics simulations of lipids in the OPLS-aa force field using the GROMACS package. This is the first systematic parameterization of lipid molecules in this force field. Topologies are provided for four phosphatidylcholines: saturated DPPC, mono-cis unsaturated POPC and DOPC, and mono-trans unsaturated PEPC. Parameterization of the phosphatidylcholines was achieved in two steps: first, we supplemented the OPLS force field parameters for DPPC with new parameters for torsion angles and van der Waals parameters for the carbon and hydrogen atoms in the acyl chains, as well as new partial atomic charges and parameters for torsion angles in the phosphatidylcholine and glycerol moieties [1]. Next, we derived parameters for the cis and trans double bonds and the neighboring them single bonds [2]. Additionally, we provide GROMACS input files with parameters describing simulation conditions (md.mdp), which are strongly recommended to be used with these lipids models. The data are associated with the research article "Cis and trans unsaturated phosphatidylcholine bilayers: a molecular dynamics simulation study" [2] and provided as supporting materials.

  11. Topologies, structures and parameter files for lipid simulations in GROMACS with the OPLS-aa force field: DPPC, POPC, DOPC, PEPC, and cholesterol

    PubMed Central

    Kulig, Waldemar; Pasenkiewicz-Gierula, Marta; Róg, Tomasz

    2015-01-01

    In this data article we provide topologies and force field parameters files for molecular dynamics simulations of lipids in the OPLS-aa force field using the GROMACS package. This is the first systematic parameterization of lipid molecules in this force field. Topologies are provided for four phosphatidylcholines: saturated DPPC, mono-cis unsaturated POPC and DOPC, and mono-trans unsaturated PEPC. Parameterization of the phosphatidylcholines was achieved in two steps: first, we supplemented the OPLS force field parameters for DPPC with new parameters for torsion angles and van der Waals parameters for the carbon and hydrogen atoms in the acyl chains, as well as new partial atomic charges and parameters for torsion angles in the phosphatidylcholine and glycerol moieties [1]. Next, we derived parameters for the cis and trans double bonds and the neighboring them single bonds [2]. Additionally, we provide GROMACS input files with parameters describing simulation conditions (md.mdp), which are strongly recommended to be used with these lipids models. The data are associated with the research article “Cis and trans unsaturated phosphatidylcholine bilayers: a molecular dynamics simulation study” [2] and provided as supporting materials. PMID:26568975

  12. 49 CFR 173.116 - Class 2-Assignment of hazard zone.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Class 2-Assignment of hazard zone. 173.116 Section... REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Definitions Classification, Packing Group Assignments and Exceptions for Hazardous Materials Other Than Class 1 and Class 7 § 173.116 Class 2—Assignment of hazard zone....

  13. 49 CFR 173.116 - Class 2-Assignment of hazard zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Class 2-Assignment of hazard zone. 173.116 Section... REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Definitions Classification, Packing Group Assignments and Exceptions for Hazardous Materials Other Than Class 1 and Class 7 § 173.116 Class 2—Assignment of hazard zone....

  14. Class 2 Integrons Dissemination Among Multidrug Resistance (MDR) Clones of Acinetobacter baumannii

    PubMed Central

    Ramírez, María Soledad; Morales, Amanda; Vilacoba, Elisabet; Márquez, Carolina

    2014-01-01

    Acinetobacter baumannii has emerged as a serious problem in the hospital environment at a global scale. Previous results from our laboratory showed a high frequency of class 2 integrons in A. baumannii strains from Argentina regarding the low rate of this element in A. baumannii isolates from the rest of the world. To reveal the current epidemiology of class 2 integrons, a molecular surveillance analyzing 78 multidrug resistant (MDR) A. baumannii isolates from Argentina and Uruguay was performed, exposing the presence of class 2 integron in the 36.61% of the isolates. Class 2 integron characterization showed that the typical Tn7::In2-7 array was present in 26 out of 27 intI2 positive isolates. All intI2 positive isolates contained at least one of the Tn7 transposition genes. In addition, we identified that 18 intI2 positive isolates possessed the Tn7::In2-7 within the attTn7 site. The molecular typing evidenced that clones I and IV that do not belong to widespread European clones I and II were found among the intI2 positive isolates. Our results exposed the widely dissemination of class 2 integron among MDR A. baumannii isolates from Argentina and Uruguay, also showing the persistence of two novel clones in our region, which could explain in part the high frequency of class 2 integron found in our region. PMID:22198473

  15. Novel Insights about Class 2 Integrons from Experimental and Genomic Epidemiology▿

    PubMed Central

    Ramírez, María Soledad; Piñeiro, Silvia; Centrón, Daniela

    2010-01-01

    In order to contribute to the knowledge of the architecture and epidemiology of class 2 integrons, we performed a class 2 integron molecular survey in which we analyzed 726 isolates in two bacterial populations from environmental and nonepidemiologically related clinical samples, respectively, collected from 1982 to 2007. We recovered the intI2 gene from 130 of 726 isolates, most of which were clinical isolates, and only 1 (a psychrophilic Pseudomonas sp.) was from a water sample. Unlike the widespread distribution of class 1 integrons within Gram-negative bacilli, only Acinetobacter baumannii and Enterobacter cloacae harbored class 2 integrons at a high frequency in our collection. Class 2 integrons with six novel cassette arrays were documented. Characterization of the transposition module of Tn7, the genetic platform in which class 2 integrons have always been reported, showed tns modules with a mosaic genetic structure. A bioinformatic analysis performed with the tns genes present in sequence databases, the finding of intI2 not associated with tns genes, and the genetic examination of novel tns-like genes found in three isolates indicated the possibility of the independent evolution of the two components related to horizontal gene transfer, the class 2 integrons and the Tn7 transposons. PMID:19917745

  16. 32 CFR 1639.6 - Considerations relevant to granting or denying claims for Class 2-D.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... registrant, having completed theological or divinity school, is satisfactorily pursuing a full-time graduate... 32 National Defense 6 2014-07-01 2014-07-01 false Considerations relevant to granting or denying... Considerations relevant to granting or denying claims for Class 2-D. (a) The registrant's claim for Class...

  17. 32 CFR 1639.6 - Considerations relevant to granting or denying claims for Class 2-D.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... registrant, having completed theological or divinity school, is satisfactorily pursuing a full-time graduate... 32 National Defense 6 2013-07-01 2013-07-01 false Considerations relevant to granting or denying... Considerations relevant to granting or denying claims for Class 2-D. (a) The registrant's claim for Class...

  18. 32 CFR 1639.6 - Considerations relevant to granting or denying claims for Class 2-D.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... registrant, having completed theological or divinity school, is satisfactorily pursuing a full-time graduate... 32 National Defense 6 2012-07-01 2012-07-01 false Considerations relevant to granting or denying... Considerations relevant to granting or denying claims for Class 2-D. (a) The registrant's claim for Class...

  19. 32 CFR 1639.6 - Considerations relevant to granting or denying claims for Class 2-D.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... registrant, having completed theological or divinity school, is satisfactorily pursuing a full-time graduate... 32 National Defense 6 2011-07-01 2011-07-01 false Considerations relevant to granting or denying... Considerations relevant to granting or denying claims for Class 2-D. (a) The registrant's claim for Class...

  20. CLASS2: accurate and efficient splice variant annotation from RNA-seq reads

    PubMed Central

    Song, Li; Sabunciyan, Sarven; Florea, Liliana

    2016-01-01

    Next generation sequencing of cellular RNA is making it possible to characterize genes and alternative splicing in unprecedented detail. However, designing bioinformatics tools to accurately capture splicing variation has proven difficult. Current programs can find major isoforms of a gene but miss lower abundance variants, or are sensitive but imprecise. CLASS2 is a novel open source tool for accurate genome-guided transcriptome assembly from RNA-seq reads based on the model of splice graph. An extension of our program CLASS, CLASS2 jointly optimizes read patterns and the number of supporting reads to score and prioritize transcripts, implemented in a novel, scalable and efficient dynamic programming algorithm. When compared against reference programs, CLASS2 had the best overall accuracy and could detect up to twice as many splicing events with precision similar to the best reference program. Notably, it was the only tool to produce consistently reliable transcript models for a wide range of applications and sequencing strategies, including ribosomal RNA-depleted samples. Lightweight and multi-threaded, CLASS2 requires <3GB RAM and can analyze a 350 million read set within hours, and can be widely applied to transcriptomics studies ranging from clinical RNA sequencing, to alternative splicing analyses, and to the annotation of new genomes. PMID:26975657

  1. Depressurization-induced gas production from Class 1 and Class 2hydrate deposits

    SciTech Connect

    Moridis, George J.; Kowalsky, Michael

    2006-05-12

    Class 1 hydrate deposits are characterized by a Hydrate-Bearing Layer (HBL) underlain by a two-phase zone involving mobile gas. Such deposits are further divided to Class 1W (involving water and hydrate in the HBL) and Class 1G (involving gas and hydrate in the HBL). In Class 2 deposits, a mobile water zone underlies the hydrate zone. Methane is the main hydrate-forming gas in natural accumulations. Using TOUGH-FX/HYDRATE to study the depressurization-induced gas production from such deposits, we determine that large volumes of gas could be readily produced at high rates for long times using conventional technology. Dissociation in Class 1W deposits proceeds in distinct stages, but is continuous in Class 1G deposits. Hydrates are shown to contribute significantly to the production rate (up to 65 percent and 75 percent in Class 1W and 1G, respectively) and to the cumulative volume of produced gas (up to 45 percent and 54 percent in Class 1W and 1G, respectively). Large volumes of hydrate-originating CH4 could be produced from Class 2 hydrates, but a relatively long lead time would be needed before gas production (which continuously increases over time) attains a substantial level. The permeability of the confining boundaries plays a significant role in gas production from Class 2 deposits. In general, long-term production is needed to realize the full potential of the very promising Class 1 and Class 2 hydrate deposits.

  2. Nematode and Arthropod Genomes Provide New Insights into the Evolution of Class 2 B1 GPCRs

    PubMed Central

    Cardoso, João C. R.; Félix, Rute C.; Power, Deborah M.

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes. PMID:24651821

  3. Nematode and arthropod genomes provide new insights into the evolution of class 2 B1 GPCRs.

    PubMed

    Cardoso, João C R; Félix, Rute C; Power, Deborah M

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes.

  4. Bottle feeding, increased overjet and Class 2 primary canine relationship: is there any association?

    PubMed

    Jabbar, Nadia Salem Abdel; Bueno, Ana Beatriz Miguel; Silva, Patrícia Elaine da; Scavone-Junior, Helio; Inês Ferreira, Rívea

    2011-01-01

    The aim of this study was to investigate the association between bottle feeding and prevalence rates of increased overjet and Class 2 primary canine relationship. The sample consisted of 911 children (461 boys, 450 girls) aged 3 (13.9%), 4 (40.8%), 5 (34%) and 6 (11.3%) years, with complete primary dentition. Information about nutritive and nonnutritive (pacifier and/or digit) sucking habits was collected through questionnaires. Three calibrated dentists (κ: 0.9-1.0 and Rs > 0.90) performed the clinical assessments. The children were divided into four groups: G1 - not bottle-fed; G2 - exclusively bottle-fed; G3 - breast- and bottle-fed, bottle feeding ceased before 3 years of age; and G4 - breast- and bottle-fed, bottle feeding ceased between 3 and 4 years of age. Associations between nutritive and nonnutritive sucking behaviors and the malocclusions studied were analyzed by multiple binary logistic regression (α= 0.05). The frequencies of increased overjet were: 25.3% (G1), 38.8% (G2), 39.2% (G3) and 47.8% (G4). The percentages of Class 2 canine relationship were: 27.9% (G1), 48.8% (G2), 43.4% (G3) and 43% (G4). No significant effect of bottle feeding was found. The chances of diagnosing increased overjet (O.R. = 4.42, p < 0.001) and Class 2 canine relationship (O.R. = 4.02, p < 0.001) were greater for children with pacifier and/or digit-sucking habits, compared to those without a history of nonnutritive sucking behavior. It may be suggested that bottle feeding alone is not directly associated with higher prevalence rates of increased overjet and Class 2 canine relationship in the primary dentition.

  5. Sensitivity Analysis of Gas Production from Class 2 and Class 3 Hydrate Deposits

    SciTech Connect

    Reagan, Matthew; Moridis, George; Zhang, Keni

    2008-05-01

    Gas hydrates are solid crystalline compounds in which gas molecules are lodged within the lattices of an ice-like crystalline solid. The vast quantities of hydrocarbon gases trapped in hydrate formations in the permafrost and in deep ocean sediments may constitute a new and promising energy source. Class 2 hydrate deposits are characterized by a Hydrate-Bearing Layer (HBL) that is underlain by a saturated zone of mobile water. Class 3 hydrate deposits are characterized by an isolated Hydrate-Bearing Layer (HBL) that is not in contact with any hydrate-free zone of mobile fluids. Both classes of deposits have been shown to be good candidates for exploitation in earlier studies of gas production via vertical well designs - in this study we extend the analysis to include systems with varying porosity, anisotropy, well spacing, and the presence of permeable boundaries. For Class 2 deposits, the results show that production rate and efficiency depend strongly on formation porosity, have a mild dependence on formation anisotropy, and that tighter well spacing produces gas at higher rates over shorter time periods. For Class 3 deposits, production rates and efficiency also depend significantly on formation porosity, are impacted negatively by anisotropy, and production rates may be larger, over longer times, for well configurations that use a greater well spacing. Finally, we performed preliminary calculations to assess a worst-case scenario for permeable system boundaries, and found that the efficiency of depressurization-based production strategies are compromised by migration of fluids from outside the system.

  6. Comparison of enterotoxic activities of heat-stable enterotoxins from class 1 and class 2 Escherichia coli of swine origin.

    PubMed Central

    Whipp, S C; Moon, H W; Argenzio, R A

    1981-01-01

    Pig small intestine develops age-dependent resistance to some (class 2 strains) enterotoxigenic Escherichia coli while remaining susceptible to others (class 1 strains). This study tested the hypothesis that class 1 and class 2 strains produce different subtypes of heat-stable enterotoxin (ST). The dose-response curves of small intestine to crude ST preparations from a class 1 and a class 2 strain were compared in several species. In infant mice, the class 1 ST preparation was less active than the class 2 ST preparation, whereas in rabbits the preparations were equally potent. However, in 1-, 7-, and 14-week-old pigs, the class 1 ST preparation was more active than the class 2 preparation. At low doses, both preparations caused reduced absorption in pigs of all three age groups, and at high doses the class 1 preparation caused secretion in all three age groups. In contrast, at high doses the class 2 preparation caused secretion in 1-week-old pigs but only reduced absorption in older pigs. when class 1 and class 2 ST preparations were fractionated by methanol extraction, in both cases the mouse-negative, pig-positive activity was associated with the methanol-insoluble fraction and mouse-positive, pig-positive activity was associated with the methanol-soluble fraction. The results are consistent with a hypothesis that class 1 and class 2 strains of enterotoxigenic E. coli produce different subtypes of ST and that the response of pig intestine to ST varies with both age and toxin subtype. PMID:7011991

  7. Measurement and analysis of magnetic field variation during a class 2b flare

    NASA Technical Reports Server (NTRS)

    Tanaka, K.

    1978-01-01

    A digital analysis of high-time-resolution videomagnetograms taken during a class 2b flare that occurred at 60 deg east is reported. The data were obtained at the Big Bear Observatory and calibrated by a Mt. Wilson magnetogram. Changes of weak magnetic fields (less than 100 G) with an amplitude of 30% to 100% have been detected over 55% of the optical flare region, apparently taking place at the initial phase of the flare. Statistical considerations suggest a real flare association with most of these changes. H-alpha observations show that large changes took place over the footpoints of heavily inclined structures like penumbral fibrils, while smaller changes took place over the plage region. An apparent polarity reversal was found at the feet of erupted fibrils. Based on force-free field calculations these changes can be reasonably explained as a transformation of the current-carrying fields to potential fields which produced large changes in the field-line inclination and rotation.

  8. Complex structure of a bacterial class 2 histone deacetylase homologue with a trifluoromethylketone inhibitor

    SciTech Connect

    Nielsen, Tine Kragh; Hildmann, Christian; Riester, Daniel; Wegener, Dennis; Schwienhorst, Andreas; Ficner, Ralf

    2007-04-01

    The crystal structure of HDAH FB188 in complex with a trifluoromethylketone at 2.2 Å resolution is reported and compared to a previously determined inhibitor complex. Histone deacetylases (HDACs) have emerged as attractive targets in anticancer drug development. To date, a number of HDAC inhibitors have been developed and most of them are hydroxamic acid derivatives, typified by suberoylanilide hydroxamic acid (SAHA). Not surprisingly, structural information that can greatly enhance the design of novel HDAC inhibitors is so far only available for hydroxamic acids in complex with HDAC or HDAC-like enzymes. Here, the first structure of an enzyme complex with a nonhydroxamate HDAC inhibitor is presented. The structure of the trifluoromethyl ketone inhibitor 9,9,9-trifluoro-8-oxo-N-phenylnonanamide in complex with bacterial FB188 HDAH (histone deacetylase-like amidohydrolase from Bordetella/Alcaligenes strain FB188) has been determined. HDAH reveals high sequential and functional homology to human class 2 HDACs and a high structural homology to human class 1 HDACs. Comparison with the structure of HDAH in complex with SAHA reveals that the two inhibitors superimpose well. However, significant differences in binding to the active site of HDAH were observed. In the presented structure the O atom of the trifluoromethyl ketone moiety is within binding distance of the Zn atom of the enzyme and the F atoms participate in interactions with the enzyme, thereby involving more amino acids in enzyme–inhibitor binding.

  9. Improved Oil Recovery in Mississippian Carbonate Reservoirs of Kansas -- Near-Term -- Class 2

    SciTech Connect

    Carr, Timothy R.; Green, Don W.; Willhite, G. Paul

    1999-07-08

    This report describes progress during the third year of the project entitled ''Improved Oil Recovery in Mississippian Carbonate Reservoirs in Kansas''. This project funded under the Department of Energy's Class 2 program targets improving the reservoir performance of mature oil fields located in shallow shelf carbonate reservoirs. The focus of this project is development and demonstration of cost-effective reservoir description and management technologies to extend the economic life of mature reservoirs in Kansas and mid-continent. The project introduced a number of potentially useful technologies, and demonstrated these technologies in actual oil field operations. Advanced technology was tailored specifically to the scale appropriate to the operations of Kansas producers. An extensive technology transfer effort is ongoing. Traditional technology transfer methods (e.g., publications and workshops) are supplemented with a public domain relational database and an online package of project results that is available through the Internet. The goal is to provide the independent complete access to project data, project results and project technology on their desktop. Included in this report is a summary of significant project results at the demonstration site (Schaben Field, Ness County, Kansas). The value of cost-effective techniques for reservoir characterization and simulation at Schaben Field were demonstrated to independent operators. All major operators at Schaben have used results of the reservoir management strategy to locate and drill additional infill locations. At the Schaben Demonstration Site, the additional locations resulted in incremental production increases of 200 BOPD from a smaller number of wells.

  10. IMPROVED OIL RECOVERY IN MISSISSIPPIAN CARBONATE RESERVOIRS OF KANSAS--NEAR TERM--CLASS 2

    SciTech Connect

    Timothy R. Carr; Don W. Green; G. Paul Willhite

    1999-06-01

    This annual report describes progress during the third year of the project entitled ''Improved Oil Recovery in Mississippian Carbonate Reservoirs in Kansas''. This project funded under the Department of Energy's Class 2 program targets improving the reservoir performance of mature oil fields located in shallow shelf carbonate reservoirs. The focus of this project is development and demonstration of cost-effective reservoir description and management technologies to extend the economic life of mature reservoirs in Kansas and the mid-continent. The project introduced a number of potentially useful technologies, and demonstrated these technologies in actual oil field operations. Advanced technology was tailored specifically to the scale appropriate to the operations of Kansas producers. An extensive technology transfer effort is ongoing. Traditional technology transfer methods (e.g., publications and workshops) are supplemented with a public domain relational database and an online package of project results that is available through the Internet. The goal is to provide the independent complete access to project data, project results and project technology on their desktop. Included in this report is a summary of significant project results at the demonstration site (Schaben Field, Ness County, Kansas). The value of cost-effective techniques for reservoir characterization and simulation at Schaben Field were demonstrated to independent operators. All major operators at Schaben have used results of the reservoir management strategy to locate and drill additional infill locations. At the Schaben Demonstration Site, the additional locations resulted in incremental production increases of 200 BOPD from a smaller number of wells.

  11. Genetic relatedness among isolates of Shigella sonnei carrying class 2 integrons in Tehran, Iran, 2002–2003

    PubMed Central

    Ranjbar, Reza; Aleo, Aurora; Giammanco, Giovanni M; Dionisi, Anna Maria; Sadeghifard, Nourkhoda; Mammina, Caterina

    2007-01-01

    Background Shigella spp. are major cause of diarrhoeal disease in both developing and developed countries. Shigella sonnei is the serogroup of Shigella most frequently responsible for sporadic and epidemic enteritis in developed countries. In recent years the emergence and spread of S. sonnei biotype g carrying class 2 integron have been frequently reported in many countries. Recently, S. sonnei has been reported as the prevalent serogroup of Shigella in Iran. The present study was carried out to investigate phenotypic and genetic characteristics of Shigella sonnei isolates identified in the years 2002 and 2003 in Tehran, Iran. Methods Biotyping, drug susceptibility testing, pulsed field gel electrophoresis (PFGE) and analysis of class 2 integrons have been carried out on 60 S. sonnei isolates, including 57 sporadic isolates from paediatric cases of shigellosis occurring in 2002 and 2003, two sporadic isolates recovered in 1984 and the ATCC 9290 strain. Results Biotype g and resistance to streptomycin, sulfamethoxazole-trimethoprim and tetracycline were exhibited by 54 of the 57 recent isolates. Of the 54 biotype g isolates, 28 exhibited a class 2 integron of 2161 bp, and 24 a class 2 integron of 1371 bp, respectively. Class 2 integrons were not detected in four isolates only, including the two endemic isolates recovered in 1984 and two strains from recent sporadic cases. PFGE divided the strains into eight pulsotypes labeled A to H, three major pulsotypes – A to C – including the large majority of the recent sporadic S. sonnei isolates. Pulsotypes A and C were the most prevalent groups, accounting for 41.6% and 35.0%, respectively, of the isolates under study. Conclusion The results suggest that biotype g, class 2 integron carrying S. sonnei are prevalent in our geographic area. S. sonnei isolated in the years 2002 and 2003 could be attributed to a few predominant clusters including, respectively, strains with pulsotypes B and C carrying a 2161 bp class 2

  12. IMPROVED OIL RECOVERY IN MISSISSIPPIAN CARBONATE RESERVOIRS OF KANSAS - NEAR TERM - CLASS 2

    SciTech Connect

    Timothy R. Carr; Don W. Green; G. Paul Willhite

    2000-04-30

    This annual report describes progress during the final year of the project entitled ''Improved Oil Recovery in Mississippian Carbonate Reservoirs in Kansas''. This project funded under the Department of Energy's Class 2 program targets improving the reservoir performance of mature oil fields located in shallow shelf carbonate reservoirs. The focus of the project was development and demonstration of cost-effective reservoir description and management technologies to extend the economic life of mature reservoirs in Kansas and the mid-continent. As part of the project, tools and techniques for reservoir description and management were developed, modified and demonstrated, including PfEFFER spreadsheet log analysis software. The world-wide-web was used to provide rapid and flexible dissemination of the project results through the Internet. A summary of demonstration phase at the Schaben and Ness City North sites demonstrates the effectiveness of the proposed reservoir management strategies and technologies. At the Schaben Field, a total of 22 additional locations were evaluated based on the reservoir characterization and simulation studies and resulted in a significant incremental production increase. At Ness City North Field, a horizontal infill well (Mull Ummel No.4H) was planned and drilled based on the results of reservoir characterization and simulation studies to optimize the location and length. The well produced excellent and predicted oil rates for the first two months. Unexpected presence of vertical shale intervals in the lateral resulted in loss of the hole. While the horizontal well was not economically successful, the technology was demonstrated to have potential to recover significant additional reserves in Kansas and the Midcontinent. Several low-cost approaches were developed to evaluate candidate reservoirs for potential horizontal well applications at the field scale, lease level, and well level, and enable the small independent producer to identify

  13. 14 CFR 101.25 - Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Power Rockets and Class 3-Advanced High Power Rockets. 101.25 Section 101.25 Aeronautics and Space... OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.25 Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets. When...

  14. 14 CFR 101.25 - Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Power Rockets and Class 3-Advanced High Power Rockets. 101.25 Section 101.25 Aeronautics and Space... OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.25 Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets. When...

  15. 14 CFR 101.25 - Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Power Rockets and Class 3-Advanced High Power Rockets. 101.25 Section 101.25 Aeronautics and Space... OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.25 Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets. When...

  16. 14 CFR 101.25 - Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Power Rockets and Class 3-Advanced High Power Rockets. 101.25 Section 101.25 Aeronautics and Space... OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.25 Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets. When...

  17. 14 CFR 101.25 - Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Power Rockets and Class 3-Advanced High Power Rockets. 101.25 Section 101.25 Aeronautics and Space... OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.25 Operating limitations for Class 2-High Power Rockets and Class 3-Advanced High Power Rockets. When...

  18. Class 2 aldehyde dehydrogenase. Characterization of the hamster enzyme, sensitive to daidzin and conserved within the family of multiple forms.

    PubMed

    Hjelmqvist, L; Lundgren, R; Norin, A; Jörnvall, H; Vallee, B; Klyosov, A; Keung, W M

    1997-10-13

    Mitochondrial (class 2) hamster aldehyde dehydrogenase has been purified and characterized. Its primary structure has been determined and correlated with the tertiary structure recently established for this class from another species. The protein is found to represent a constant class within a complex family of multiple forms. Variable segments that occur in different species correlate with non-functional segments, in the same manner as in the case of the constant class of alcohol dehydrogenases (class III type) of another protein family, but distinct from the pattern of the corresponding variable enzymes. Hence, in both these protein families, overall variability and segment architectures behave similarly, with at least one 'constant' form in each case, class III in the case of alcohol dehydrogenases, and at least class 2 in the case of aldehyde dehydrogenases.

  19. Molecular diversity of class 2 integrons in antibiotic-resistant gram-negative bacteria found in wastewater environments in China.

    PubMed

    Xia, Ruirui; Ren, Ye; Guo, Xianhu; Xu, Hai

    2013-03-01

    The molecular architecture of class 2 integrons among gram-negative bacteria from wastewater environments was investigated in Jinan, China. Out of the 391 antibiotic-resistant bacteria found, 38 isolates harboring class 2 integrons encoding potentially transferrable genes that could confer antibiotic resistance were found. These isolates were classified into 19 REP-PCR types. These strains were identified using 16S rRNA gene sequencing and found to be as follows: Proteus mirabilis (16), Escherichia coli (7), Providencia spp. (7), Proteus spp. (2), P. vulgaris (3), Shigella sp. (1), Citrobacter freundii (1), and Acinetobacter sp. (1). Their class 2 integron cassette arrays were amplified and then either analyzed using PCR-RFLP or sequenced. The typical array dfrA1-sat2-aadA1 was detected in 27 isolates. Six atypical arrays were observed, including three kinds of novel arrangements (linF2(∆attC1)-dfrA1(∆attC2)-aadA1-orf441 or linF2(∆attC1)-dfrA1(∆attC2)-aadA1, dfrA1-catB2-sat2-aadA1, and estX(Vr)-sat2-aadA1) and a hybrid with the 3'CS of class 1 integrons (dfrA1-sat2-aadA1-qacH), and dfrA1-sat1. Twenty-four isolates were also found to carry class 1 integrons with 10 types of gene cassette arrays. Several non-integron-associated antibiotic resistance genes were found, and their transferability was investigated. Results showed that water sources in the Jinan region harbored a diverse community of both typical and atypical class 2 integrons, raising concerns about the overuse of antibiotics and their careless disposal into the environment.

  20. Randomised controlled trial comparing European standard class 1 to class 2 compression stockings for ulcer recurrence and patient compliance.

    PubMed

    Clarke-Moloney, Mary; Keane, Niamh; O'Connor, Veronica; Ryan, Mary Anna; Meagher, Helen; Grace, Pierce A; Kavanagh, Eamon; Walsh, Stewart R; Burke, Paul E

    2014-08-01

    The aim of this study was to determine the rate of venous ulcer recurrence and the level of compliance in patients wearing European class 1 or class 2 compression stockings. A total of 100 patients with healed venous leg ulcers were recruited, and were randomised to either class 1 (n = 50) or class 2 (n = 50) compression stockings. Follow-up was at 1 week, 3, 6, 9 and 12 months to monitor ulcer recurrence and compliance. Patients had a duplex scan to identify the source of venous incompetence. The rate of ulcer recurrence after 12 months was 16·1%, and the difference in recurrence rate between classes was not statistically significant (P = 0·287) although greater numbers in class 1 developed a recurrence. Participants (88·9%) were compliant; non-compliant patients were at a significantly greater risk of recurrence (P≤ 0·0001). Thirteen patients had both superficial and deep incompetence; those randomised to class 1 stockings (n = 4) developed ulcer recurrence. Patients with a history of multiple episodes of ulceration were more likely to develop a recurrence (P = 0·001). The lowest venous ulcer recurrence rates were seen in patients who were compliant with hosiery regardless of the compression level. Patients with both superficial and deep incompetence had a lower rate of recurrence with class 2 compression.

  1. Development and Implementation of a Battery-Electric Light-Duty Class 2a Truck including Hybrid Energy Storage

    NASA Astrophysics Data System (ADS)

    Kollmeyer, Phillip J.

    This dissertation addresses two major related research topics: 1) the design, fabrication, modeling, and experimental testing of a battery-electric light-duty Class 2a truck; and 2) the design and evaluation of a hybrid energy storage system (HESS) for this and other vehicles. The work begins with the determination of the truck's peak power and wheel torque requirements (135kW/4900Nm). An electric traction system is then designed that consists of an interior permanent magnet synchronous machine, two-speed gearbox, three-phase motor drive, and LiFePO4 battery pack. The battery pack capacity is selected to achieve a driving range similar to the 2011 Nissan Leaf electric vehicle (73 miles). Next, the demonstrator electric traction system is built and installed in the vehicle, a Ford F150 pickup truck, and an extensive set of sensors and data acquisition equipment is installed. Detailed loss models of the battery pack, electric traction machine, and motor drive are developed and experimentally verified using the driving data. Many aspects of the truck's performance are investigated, including efficiency differences between the two-gear configuration and the optimal gear selection. The remainder focuses on the application of battery/ultracapacitor hybrid energy storage systems (HESS) to electric vehicles. First, the electric truck is modeled with the addition of an ultracapacitor pack and a dc/dc converter. Rule-based and optimal battery/ultracapacitor power-split control algorithms are then developed, and the performance improvements achieved for both algorithms are evaluated for operation at 25°C. The HESS modeling is then extended to low temperatures, where battery resistance increases substantially. To verify the accuracy of the model-predicted results, a scaled hybrid energy storage system is built and the system is tested for several drive cycles and for two temperatures. The HESS performance is then modeled for three variants of the vehicle design, including the

  2. Epigenetic reprogramming and aberrant expression of PRAME are associated with increased metastatic risk in Class 1 and Class 2 uveal melanomas

    PubMed Central

    Field, Matthew G.; Durante, Michael A.; Decatur, Christina L.; Tarlan, Bercin; Oelschlager, Kristen M.; Stone, John F.; Kuznetsov, Jeffim; Bowcock, Anne M.; Kurtenbach, Stefan; Harbour, J. William

    2016-01-01

    Background We previously identified PRAME as a biomarker for metastatic risk in Class 1 uveal melanomas. In this study, we sought to define a threshold value for positive PRAME expression (PRAME+) in a large dataset, identify factors associated with PRAME expression, evaluate the prognostic value of PRAME in Class 2 uveal melanomas, and determine whether PRAME expression is associated with aberrant hypomethylation of the PRAME promoter. Results Among 678 samples analyzed by qPCR, 498 (73.5%) were PRAME- and 180 (26.5%) were PRAME+. Class 1 tumors were more likely to be PRAME-, whereas Class 2 tumors were more likely to be PRAME+ (P < 0.0001). PRAME expression was associated with shorter time to metastasis and melanoma specific mortality in Class 2 tumors (P = 0.01 and P = 0.02, respectively). In Class 1 tumors, PRAME expression was directly associated with SF3B1 mutations (P < 0.0001) and inversely associated with EIF1AX mutations (P = 0.004). PRAME expression was strongly associated with hypomethylation at 12 CpG sites near the PRAME promoter. MATERIALS AND METHODS Analyses included PRAME mRNA expression, Class 1 versus Class 2 status, chromosomal copy number, mutation status of BAP1, EIF1AX, GNA11, GNAQ and SF3B1, and genomic DNA methylation status. Analyses were performed on 555 de-identified samples from Castle Biosciences, 123 samples from our center, and 80 samples from the TCGA. Conclusions PRAME is aberrantly hypomethylated and activated in Class 1 and Class 2 uveal melanomas and is associated with increased metastatic risk in both classes. Since PRAME has been successfully targeted for immunotherapy, it may prove to be a companion prognostic biomarker. PMID:27486988

  3. The bacterial-type phosphoenolpyruvate carboxylase isozyme from developing castor oil seeds is subject to in vivo regulatory phosphorylation at serine-451.

    PubMed

    Dalziel, Katie J; O'Leary, Brendan; Brikis, Carolyne; Rao, Srinath K; She, Yi-Min; Cyr, Terry; Plaxton, William C

    2012-04-05

    Phosphoenolpyruvate carboxylase (PEPC) is a tightly controlled anaplerotic enzyme situated at a pivotal branch point of plant carbohydrate-metabolism. In developing castor oil seeds (COS) a novel allosterically-densensitized 910-kDa Class-2 PEPC hetero-octameric complex arises from a tight interaction between 107-kDa plant-type PEPC and 118-kDa bacterial-type PEPC (BTPC) subunits. Mass spectrometry and immunoblotting with anti-phosphoSer451 specific antibodies established that COS BTPC is in vivo phosphorylated at Ser451, a highly conserved target residue that occurs within an intrinsically disordered region. This phosphorylation was enhanced during COS development or in response to depodding. Kinetic characterization of a phosphomimetic (S451D) mutant indicated that Ser451 phosphorylation inhibits the catalytic activity of BTPC subunits within the Class-2 PEPC complex.

  4. Randomized Phase II Trial of High-Dose Melatonin and Radiation Therapy for RPA Class 2 Patients With Brain Metastases (RTOG 0119)

    SciTech Connect

    Berk, Lawrence . E-mail: Berklb@moffitt.usf.edu; Berkey, Brian; Rich, Tyvin; Hrushesky, William; Gallagher, Michael; Kudrimoti, Mahesh; McGarry, Ronald C.; Suh, John; Mehta, Minesh

    2007-07-01

    Purpose: To determine if high-dose melatonin for Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) Class 2 patients with brain metastases improved survival over historical controls, and to determine if the time of day melatonin was given affected its toxicity or efficacy. RTOG 0119 was a phase II randomized trial for this group of patients. Methods and Materials: RTOG RPA Class 2 patients with brain metastases were randomized to 20 mg of melatonin, given either in the morning (8-9 AM) or in the evening (8-9 PM). All patients received radiation therapy (30 Gy in 10 fractions) in the afternoon. Melatonin was continued until neurologic deterioration or death. The primary endpoint was overall survival time. Neurologic deterioration, as reflected by the Mini-Mental Status Examination, was also measured. Results: Neither of the randomized groups had survival distributions that differed significantly from the historic controls of patients treated with whole-brain radiotherapy. The median survivals of the morning and evening melatonin treatments were 3.4 and 2.8 months, while the RTOG historical control survival was 4.1 months. Conclusions: High-dose melatonin did not show any beneficial effect in this group of patients.

  5. Dissemination of Trimethoprim-Sulfamethoxazole Drug Resistance Genes Associated with Class 1 and Class 2 Integrons Among Gram-Negative Bacteria from HIV Patients in South India.

    PubMed

    Ramesh Kumar, Marimuthu Ragavan; Arunagirinathan, Narasingam; Srivani, Seetharaman; Dhanasezhian, Aridoss; Vijaykanth, Nallusamy; Manikandan, Natesan; Balakrishnan, Sethuramalingam; Vignesh, Ramachandran; Balakrishnan, Pachamuthu; Solomon, Suniti; Solomon, Sunil S

    2016-11-17

    The antibiotic, trimethoprim-sulfamethoxazole (TMP-SMX), is generally used for prophylaxis in HIV individuals to protect them from Pneumocystis jiroveci infection. Long-term use of TMP-SMX develops drug resistance among bacteria in HIV patients. The study was aimed to detect the TMP-SMX resistance genes among gram-negative bacteria from HIV patients. TMP-SMX-resistant isolates were detected by the Kirby-Bauer disc diffusion method. While TMP resistance genes such as dfrA1, dfrA5, dfrA7, and dfrA17 and SMX resistance genes such as sul1 and sul2 were detected by multiplex PCR, class 1 and class 2 integrons were detected by standard monoplex PCR. Of the 151 TMP-SMX-resistant bacterial isolates, 3 were positive for sul1 alone, 48 for sul2 alone, 11 for dfrA7 alone, 21 for sul1 and sul2, 1 for sul1 and dfrA7, 23 for sul2 and dfrA7, 2 for sul2 and dfrA5, 41 for sul1, sul2, and dfrA7, and 1 for sul2, dfrA5, and dfrA7. Of 60 TMP-SMX-resistant isolates positive for integrons, 44 had class 1 and 16 had class 2 integrons. It was found that the prevalence of sul genes (n = 202; p < 0.001) was higher compared with dfr genes (n = 80; p < 0.001), and 87.4% (n = 132; p < 0.001) of TMP-SMX-resistant isolates also were positive for β-lactamase production. This type of study is reported for the first time from HIV patients in India. Therefore, this study indicates that dissemination of TMP-SMX resistance genes and class 1 and class 2 integrons along with β-lactamase production among gram-negative bacteria in HIV patients will certainly make their treatment to bacterial infections more complicated in clinical settings.

  6. Bacterial- and plant-type phosphoenolpyruvate carboxylase isozymes from developing castor oil seeds interact in vivo and associate with the surface of mitochondria.

    PubMed

    Park, Joonho; Khuu, Nicholas; Howard, Alexander S M; Mullen, Robert T; Plaxton, William C

    2012-07-01

    Phosphoenolpyruvate carboxylase (PEPC) from developing castor oil seeds (COS) exists as two distinct oligomeric isoforms. The typical class-1 PEPC homotetramer consists of 107-kDa plant-type PEPC (PTPC) subunits, whereas the allosterically desensitized 910-kDa class-2 PEPC hetero-octamer arises from the association of class-1 PEPC with 118-kDa bacterial-type PEPC (BTPC) subunits. The in vivo interaction and subcellular location of COS BTPC and PTPC were assessed by imaging fluorescent protein (FP)-tagged PEPCs in tobacco suspension-cultured cells. The BTPC-FP mainly localized to cytoplasmic punctate/globular structures, identified as mitochondria by co-immunostaining of endogenous cytochrome oxidase. Inhibition of respiration with KCN resulted in proportional decreases and increases in mitochondrial versus cytosolic BTPC-FP, respectively. The FP-PTPC and NLS-FP-PTPC (containing an appended nuclear localization signal, NLS) localized to the cytosol and nucleus, respectively, but both co-localized with mitochondrial-associated BTPC when co-expressed with BTPC-FP. Transmission electron microscopy of immunogold-labeled developing COS revealed that BTPC and PTPC are localized at the mitochondrial (outer) envelope, as well as the cytosol. Moreover, thermolysin-sensitive BTPC and PTPC polypeptides were detected on immunoblots of purified COS mitochondria. Overall, our results demonstrate that: (i) COS BTPC and PTPC interact in vivo as a class-2 PEPC complex that associates with the surface of mitochondria, (ii) BTPC's unique and divergent intrinsically disordered region mediates its interaction with PTPC, whereas (iii) the PTPC-containing class-1 PEPC is entirely cytosolic. We hypothesize that mitochondrial-associated class-2 PEPC facilitates rapid refixation of respiratory CO(2) while sustaining a large anaplerotic flux to replenish tricarboxylic acid cycle C-skeletons withdrawn for biosynthesis.

  7. Phosphorylation of bacterial-type phosphoenolpyruvate carboxylase at Ser425 provides a further tier of enzyme control in developing castor oil seeds.

    PubMed

    O'Leary, Brendan; Rao, Srinath K; Plaxton, William C

    2011-01-01

    PEPC [PEP (phosphoenolpyruvate) carboxylase] is a tightly controlled anaplerotic enzyme situated at a pivotal branch point of plant carbohydrate metabolism. Two distinct oligomeric PEPC classes were discovered in developing COS (castor oil seeds). Class-1 PEPC is a typical homotetramer of 107 kDa PTPC (plant-type PEPC) subunits, whereas the novel 910-kDa Class-2 PEPC hetero-octamer arises from a tight interaction between Class-1 PEPC and 118 kDa BTPC (bacterial-type PEPC) subunits. Mass spectrometric analysis of immunopurified COS BTPC indicated that it is subject to in vivo proline-directed phosphorylation at Ser425. We show that immunoblots probed with phosphorylation site-specific antibodies demonstrated that Ser425 phosphorylation is promoted during COS development, becoming maximal at stage IX (maturation phase) or in response to depodding. Kinetic analyses of a recombinant, chimaeric Class-2 PEPC containing phosphomimetic BTPC mutant subunits (S425D) indicated that Ser425 phosphorylation results in significant BTPC inhibition by: (i) increasing its Km(PEP) 3-fold, (ii) reducing its I50 (L-malate and L-aspartate) values by 4.5- and 2.5-fold respectively, while (iii) decreasing its activity within the physiological pH range. The developmental pattern and kinetic influence of Ser425 BTPC phosphorylation is very distinct from the in vivo phosphorylation/activation of COS Class-1 PEPC's PTPC subunits at Ser11. Collectively, the results establish that BTPC's phospho-Ser425 content depends upon COS developmental and physiological status and that Ser425 phosphorylation attenuates the catalytic activity of BTPC subunits within a Class-2 PEPC complex. To the best of our knowledge, this study provides the first evidence for protein phosphorylation as a mechanism for the in vivo control of vascular plant BTPC activity.

  8. Improved oil recovery in Mississippian carbonate reservoirs of Kansas: Near term, Class 2. [Annual report], September 18, 1994--October 1, 1995. Draft.

    SciTech Connect

    Carr, T.R.; Green, D.W.; Willhite, G.P.

    1996-01-01

    This report represents a summary of the progress during the first year of Budget period 1 of the near term Class 2 project entitled ``Improved Oil Recovery in Mississippian Carbonate Reservoirs of Kansas``. Two examples of advanced technologies developed as part of this project are highlighted along with the use of the Internet to transfer these technologies. The two advanced technologies are a spread-sheet petrophysical analysis and reservoir evaluation (PfEFFER), and a petrophysical/seismic approach to well logs (pseudoseismic). Work continues on multi-disciplinary reservoir characterization at the demonstration site. The potential for incremental primary recovery is being evaluated using the improved reservoir characterization to target infill drilling and evaluate the potential of a horizontal well. The impact of successful incremental primary recovery from sub-Pennsylvanian unconformity Mississippian reservoirs such as are present at the Schaben demonstration site would be significant for Kansas and the US.

  9. [Characterization of class 1 and class 2 integron gene cassettes in Escherichia coli strains isolated from urine cultures: a multicenter study].

    PubMed

    Çopur Çiçek, Ayşegül; Sandallı, Cemal; Budak, Emine Esra; Yağmur, Gülhan; Çizmeci, Zeynep; Ak, Sibel; Balcı, Pervin Özlem; Şay Coşkun, Safiye Umut; Ay Altıntop, Yasemin; Fırat, Mehmet; Sarı, Fatma; Çalışkan, Ahmet; Yıldız, Nazan; Sancaktar, Metin; Özgümüş, Osman Birol

    2016-04-01

    Escherichia coli is the most common pathogen isolated from both nosocomial and community acquired urinary tract infections. Although there are many studies from different centers concerning the antibiotic susceptibility of E.coli isolates in Turkey, the studies are quite few about class 1 and class 2 integron cassettes in clinical E.coli isolates from urinary samples. The aim of the study was to investigate the antibiotic susceptibility and the carriage of integron gene cassettes in E.coli strains isolated from urinary samples. A total of 626 E.coli strains isolated from urine cultures in microbiology laboratories located at 10 provinces from different regions of Turkey (Denizli, Ankara, Kayseri, Niğde, Şanlıurfa, Kahramanmaras, Tokat, Malatya, Konya and Trabzon) between June 2011-June 2012 were included in the study. The identification and antibiotic susceptibility testing of the isolates were studied by conventional methods as well as Vitek® 2 Compact (bioMérieux, France) and BD Phoenix™ 100 (Becton Dickinson, USA) systems. The antibiotic susceptibilities of all the isolates were retested by Kirby-Bauer disk diffusion method according to CLSI recommendations in the main center of the study in order to achive the standardization. The presence of integrons was detected with polymerase chain reaction (PCR) method by using specific primers targeting class 1 (intI1) and class 2 (intI2) integrase gene regions. After integron amplification the samples were cloned and subjected to DNA sequencing. When the antibiotic susceptibility of the isolates were evaluated, the highest resistance was observed against most commonly used empirical antibiotics namely ampicillin and trimethoprim-sulfamethoxazole (SXT) with the mean rate of 58.6% (range: 43.8%-73.2%) and 41.2% (range: 35.4%-45.8%), respectively. The most effective antibiotics detected against the isolates were imipenem and amikacin with the lowest resistance rates of 0.2% (range: 0%-1.1%) and 0.6% (range: 0

  10. M2/M1 Ratio of Tumor Associated Macrophages and PPAR-gamma Expression in Uveal Melanomas with Class 1 and Class 2 Molecular Profiles

    PubMed Central

    Herwig, Martina C.; Bergstrom, Chris; Wells, Jill R.; Höller, Tobias; Grossniklaus, Hans E.

    2012-01-01

    Macrophages have been found to be negative predictors of outcome in patients with uveal melanoma. In particular, recent studies point towards a disease-progressing role of proangiogenic M2 macrophages in melanomas with monosomy 3. Although most studies implicate a protective effect of PPAR-gamma activation in tumors, PPAR-gamma has also been shown to promote the polarization of M1 macrophages towards the M2 phenotype. The purpose of this investigation was first, to characterize the phenotype of tumor infiltrating macrophages and second, to study PPAR-gamma expression in uveal melanomas with molecular gene expression profile as prognostic predictors for patients’ outcome. Twenty specimens from patients with uveal melanoma were analyzed for clinical and histologic tumor characteristics. The molecular RNA profile (class 1 or class 2) was commercially determined. Using immunohistochemical techniques, the specimens were dual labeled for CD68 and CD163. CD68+CD163− M1 macrophages and CD68+CD163+ M2 macrophages were analyzed in ten high power fields sparing macrophage-poor areas and a mean value was calculated for each tumor. The tumors were immunostained for von Willebrand factor and the mean vascular density (MVD) was analyzed according to Foss. To assess the proliferative rate of each tumor, Ki67 expression was evaluated in ten high power fields followed by calculation of a mean value. Expression of PPAR-gamma was evaluated using a score from 0 (no staining) to 3 (tumor entirely stained). Statistical analysis and a respective correlation was made between histologic characteristics, molecular profile, type of tumor infiltrating macrophages (M1 versus M2), MVD, proliferative rate, and PPAR-gamma expression. Our results showed a correlation between the ratio of M2/M1 macrophages and the molecular profile with a ratio of approximately 1 corresponding to molecular class 1 and a ratio of approximately 2 corresponding to molecular class 2 (p=0.01). The ratio of M2/M1

  11. An introduction to the design and fabrication progress of a megawatt class 2G HTS motor for the ship propulsion application

    NASA Astrophysics Data System (ADS)

    Moon, Heejong; Kim, Yeong-Chun; Park, Heui-Joo; Yu, In-Keun; Park, Minwon

    2016-03-01

    This paper introduces the design and fabrication progress of a megawatt class 2G high temperature superconductor (HTS) motor for the ship propulsion application at Doosan Heavy Industries and Construction. The purpose of this 2G HTS propulsion motor is to launch the business area for marine applications such as surface ship, submarine, merchant ship etc. The principles and interpretation of the magnetic field for 2G HTS motor and permanent magnet type motors are similar on the basis of 3D design and production. The most important component of an HTS motor is the rotor, which is composed of HTS coil, non-ferrous metal, torque disk, damper, and hollow shaft. A HTS rotor using hastelloy-based 2G HTS coils was designed and built. Open-circuit and short-circuit characteristics of the superconducting motor were investigated and compared with the analysis results at reduced excitation to verify the design. Preliminary testing of a 2G HTS motor has been conducted at a few hundred kilowatts as per the design. Through these results, we anticipate that most of the design criteria can be satisfied. However, we have faced several issues during the testing of the motor and these issues need to be resolved in order to take the design further.

  12. Assistance to state underground injection control programs and the oil and gas industry with class 2 injection well data management and technology transfer. Final technical report

    SciTech Connect

    Paque, M.J.

    1995-11-23

    The Underground Injection Practices Research Foundation (UIPRF) administered a grant project funded by the US Department of Energy relating to Class 2 injection well operations in various primacy and direct implementation states throughout the country. This effort provided substantial benefits to state regulatory agencies and oil and gas producing companies. It enhanced the protection of the environment through the protection of ground water resources and improved oil and gas production operations within affected states. This project involved the following accomplishment: (1) Completed the design and installation of the only comprehensive, fully relational PC-Based Oil and Gas regulatory data management system (the Risk Based Data Management System) in the country. Additionally, training and data conversion was conduced and the RBDMS User`s Guide and the RBDMS Administrator`s Guide were completed. (2) State wide Area-Of-Review (AOR) workshop were held in California and Oklahoma and a national three-day workshop was held in Kansas City, Missouri where 24 state oil and gas agencies were represented.

  13. Class 1 and class 2 integrons in multidrug-resistant gram-negative bacteria isolated from the Salmon River, British Columbia.

    PubMed

    Xu, Hai; Broersma, Klaas; Miao, Vivian; Davies, Julian

    2011-06-01

    Using an enrichment protocol, we isolated 16 gram-negative, multidrug-resistant strains of known or opportunistic bacterial pathogens from the Salmon River in south-central British Columbia from 2005 to 2009, and investigated the genetic basis of their resistance to a variety of antibiotics. Of the 16 strains, 13 carried class 1 integrons and three carried class 2 integrons. Genes found in cassettes associated with the integrons included those for dihydrofolate reductases (dfrA1, dfrA12, dfrA17, and dfrB7), aminoglycoside adenyltransferases (aadA1, aadA2, aadA5, and aadB), streptothricin acetyltransferase (sat), and hypothetical proteins (orfF and orfC). A new gene cassette of unknown function, orf1, was discovered between dfrA1 and aadA5 in Escherichia sp. Other genes for resistance to tetracycline, chloramphenicol, streptomycin, and kanamycin (tetA, tetB, tetD; catA; strA-strB; and aphA1-Iab, respectively) were outside the integrons. Several of these resistance determinants were transferable by conjugation. The detection of organisms and resistance determinants normally associated with clinical settings attest to their widespread dispersal and suggest that regular monitoring of their presence in aquatic habitats should become a part of the overall effort to understand the epidemiology of antibiotic resistance genes in bacteria.

  14. Improved oil recovery in Mississippian carbonate reservoirs of Kansas near term Class 2. Annual report, September 18, 1994--March 15, 1997

    SciTech Connect

    Carr, T.R.; Green, D.W.; Willhite, G.P.

    1998-04-01

    This annual report describes progress during the second year of the project entitled {open_quotes}Improved Oil Recovery in Mississippian Carbonate Reservoirs in Kansas{close_quotes}. This project funded under the Department of Energy`s Class 2 program targets improving the reservoir performance of mature oil fields located in shallow shelf carbonate reservoirs. The focus of this project is development and demonstration of cost-effective reservoir description and management technologies to extend the economic life of mature reservoirs in Kansas and the mid-continent. As part of the project, several tools and techniques for reservoir description and management were developed, modified and demonstrated. These include: (1) a new approach to subsurface visualization using electric logs ({open_quotes}Pseudoseismic{open_quotes}); (2) a low-cost easy-to-use spreadsheet log analysis software (PfEFFER); and (3) an extension of the BOAST-3 computer program for full field reservoir simulation. The world-wide-web was used to provide rapid and flexible dissemination of the project results through the Internet. Included in this report is a summary of significant project results at the demonstration site (Schaben Field, Ness County, Kansas). These results include an outline of the reservoir description based on available and newly acquired data and reservoir simulation results. Detailed information is available on-line through the Internet. Based on the reservoir simulation, three infill wells will be drilled to validate the reservoir description and demonstrate the effectiveness of the proposed reservoir management strategies. The demonstration phase of the project has just begun and will be presented in the next annual report.

  15. Coimmunopurification of phosphorylated bacterial- and plant-type phosphoenolpyruvate carboxylases with the plastidial pyruvate dehydrogenase complex from developing castor oil seeds.

    PubMed

    Uhrig, R Glen; O'Leary, Brendan; Spang, H Elizabeth; MacDonald, Justin A; She, Yi-Min; Plaxton, William C

    2008-03-01

    The phosphoenolpyruvate carboxylase (PEPC) interactome of developing castor oil seed (COS; Ricinus communis) endosperm was assessed using coimmunopurification (co-IP) followed by proteomic analysis. Earlier studies suggested that immunologically unrelated 107-kD plant-type PEPCs (p107/PTPC) and 118-kD bacterial-type PEPCs (p118/BTPC) are subunits of an unusual 910-kD hetero-octameric class 2 PEPC complex of developing COS. The current results confirm that a tight physical interaction occurs between p118 and p107 because p118 quantitatively coimmunopurified with p107 following elution of COS extracts through an anti-p107-IgG immunoaffinity column. No PEPC activity or immunoreactive PEPC polypeptides were detected in the corresponding flow-through fractions. Although BTPCs lack the N-terminal phosphorylation motif characteristic of PTPCs, Pro-Q Diamond phosphoprotein staining, immunoblotting with phospho-serine (Ser)/threonine Akt substrate IgG, and phosphate-affinity PAGE established that coimmunopurified p118 was multiphosphorylated at unique Ser and/or threonine residues. Tandem mass spectrometric analysis of an endoproteinase Lys-C p118 peptide digest demonstrated that Ser-425 is subject to in vivo proline-directed phosphorylation. The co-IP of p118 with p107 did not appear to be influenced by their phosphorylation status. Because p118 phosphorylation was unchanged 48 h following elimination of photosynthate supply due to COS depodding, the signaling mechanisms responsible for photosynthate-dependent p107 phosphorylation differ from those controlling p118's in vivo phosphorylation. A 110-kD PTPC coimmunopurified with p118 and p107 when depodded COS was used. The plastidial pyruvate dehydrogenase complex (PDC(pl)) was identified as a novel PEPC interactor. Thus, a putative metabolon involving PEPC and PDC(pl) could function to channel carbon from phosphoenolpyruvate to acetyl-coenzyme A and/or to recycle CO(2) from PDC(pl) to PEPC.

  16. The peach (Prunus persica [L.] Batsch) homeobox gene KNOPE3, which encodes a class 2 knotted-like transcription factor, is regulated during leaf development and triggered by sugars.

    PubMed

    Testone, Giulio; Condello, Emiliano; Verde, Ignazio; Caboni, Emilia; Iannelli, Maria Adelaide; Bruno, Leonardo; Mariotti, Domenico; Bitonti, Maria Beatrice; Giannino, Donato

    2009-07-01

    Class 1 KNOTTED1-like transcription factors (KNOX) are known to regulate plant development, whereas information on class 2 KNOX has been limited. The peach KNOPE3 gene was cloned, belonged to a family of few class 2 members and was located at 66 cM in the Prunus spp. G1 linkage-group. The mRNA localization was diversified in leaf, stem, flower and drupe, but recurred in all organ sieves, suggesting a role in sap nutrient transport. During leaf development, the mRNA earliest localized to primordia sieves and subsequently to mesophyll cells of growing leaves. Consistently, its abundance augmented with leaf expansion. The transcription was monitored in leaves responding to darkening, supply and transport block of sugars. It peaked at 4 h after darkness and dropped under prolonged obscurity, showing a similar kinetic to that of sucrose content variation. Feeding leaflets via the transpiration stream caused KNOPE3 up-regulation at 3 h after fructose, glucose and sucrose absorption and at 12 h after sorbitol. In girdling experiments, leaf KNOPE3 was triggered from 6 h onwards along with sucrose and sorbitol raise. Both the phloem-associated expression and sugar-specific gene modulation suggest that KNOPE3 may play a role in sugar translocation during the development of agro-relevant organs such as drupe.

  17. Possible Domain Formation In PE/PC Bilayers Containing High Cholesterol

    NASA Astrophysics Data System (ADS)

    Hein, Matthew; Hussain, Fazle; Huang, Juyang

    2015-03-01

    Cholesterol is a significant component of animal cell membranes, and its presence has the effects of not only adding rigidity to the lipid bilayer, but also leading to the formation of lipid domains. Two other lipids of interest are phosphatidylethanolamine (PE), which constitutes about 45 percent of the phospholipids found in human nervous tissues, and phosphatidylcholine (PC), which is found in every cell of the human body. The maximum solubility of cholesterol is the highest mole fraction of cholesterol that the lipid bilayer can retain, at which point cholesterol begins to precipitate out to form cholesterol monohydrate crystals. We have measured the maximum solubility of cholesterol in mixtures of 16:0-18:1PE and 16:0-18:1PC using a new light scattering technique, which utilizes the anisotropic nature of light scattering by cholesterol crystals. This new method is highly accurate and reproducible. Our results show that the maximum solubility of cholesterol increases linearly as a function of the molar ratio POPC/(POPE+POPC), which suggests possible domain formation in mixtures of PE and PC containing maximum amount of cholesterol.

  18. Evaluation of materials proposed for the construction of the Plasma Electrode Pockels Cell (PEPC) on beamlet

    NASA Astrophysics Data System (ADS)

    Roberts, D.; Robb, C.; Deyoreo, J.; Atherton, J.

    1992-11-01

    The proposed upgrade of the NOVA laser system at Lawrence Livermore National Laboratory employs a multipass architecture that requires an optical switch to emit the laser light at the appropriate fluence. This Pockels cell-based optical switch does not use traditional ring or thin-film electrodes because of the large aperture and high fluence of the laser system. Rather, it uses a plasma electrode Pockels cell with a KD*P crystal as the electro-optical medium. A discharge plasma is formed on each side of the electro-optic crystal and high voltage is applied across the crystal through the plasma electrode to initiate optical switching. In October 1991 we began evaluating materials suggested for the large aperture plasma electrode optical switch. Previous experiments suggested that switching performance could be significantly affected by the deterioration of cell materials. The final prototype switch tested used polyethylene for the switch body, Mykroy for the mid-plane and a silicone vulcanite to encapsulate the KD*P crystal. The encapsulant easily compensated for the effect of assembling the optical switch and no strain-induced birefringence in the crystal after encapsulation was measured. Oxygen was eventually added to the plasma to react with the sputtered carbon from the cathode and produce a gaseous effluent. As an added benefit, the production of ozone absorbed most of the ultraviolet radiation affecting the encapsulant. All the materials tested decomposed and produced volatiles, although no change in the damage threshold of exposed optical surfaces tested to date was seen. An evaluation of the recommended materials for major cell components using published manufacturers data, experimental results from our Material Evaluation Apparatus, and outgassing performance and sputtering data produced at the Laboratory's Vacuum Process Lab is presented.

  19. Tissue-specific expression and post-translational modifications of plant- and bacterial-type phosphoenolpyruvate carboxylase isozymes of the castor oil plant, Ricinus communis L.

    PubMed

    O'Leary, Brendan; Fedosejevs, Eric T; Hill, Allyson T; Bettridge, James; Park, Joonho; Rao, Srinath K; Leach, Craig A; Plaxton, William C

    2011-11-01

    This study employs transcript profiling together with immunoblotting and co-immunopurification to assess the tissue-specific expression, protein:protein interactions, and post-translational modifications (PTMs) of plant- and bacterial-type phosphoenolpyruvate carboxylase (PEPC) isozymes (PTPC and BTPC, respectively) in the castor plant, Ricinus communis. Previous studies established that the Class-1 PEPC (PTPC homotetramer) of castor oil seeds (COS) is activated by phosphorylation at Ser-11 and inhibited by monoubiquitination at Lys-628 during endosperm development and germination, respectively. Elimination of photosynthate supply to developing COS by depodding caused the PTPC of the endosperm and cotyledon to be dephosphorylated, and then subsequently monoubiquitinated in vivo. PTPC monoubiquitination rather than phosphorylation is widespread throughout the castor plant and appears to be the predominant PTM of Class-1 PEPC that occurs in planta. The distinctive developmental patterns of PTPC phosphorylation versus monoubiquitination indicates that these two PTMs are mutually exclusive. By contrast, the BTPC: (i) is abundant in the inner integument, cotyledon, and endosperm of developing COS, but occurs at low levels in roots and cotyledons of germinated COS, (ii) shows a unique developmental pattern in leaves such that it is present in leaf buds and young expanding leaves, but undetectable in fully expanded leaves, and (iii) tightly interacts with co-expressed PTPC to form the novel and allosterically-desensitized Class-2 PEPC heteromeric complex. BTPC and thus Class-2 PEPC up-regulation appears to be a distinctive feature of rapidly growing and/or biosynthetically active tissues that require a large anaplerotic flux from phosphoenolpyruvate to replenish tricarboxylic acid cycle C-skeletons being withdrawn for anabolism.

  20. Metabolic engineering of Rhizopus oryzae: Effects of overexpressing pyc and pepc genes on fumaric acid biosynthesis from glucose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumaric acid, a dicarboxylic acid used as a food acidulant and in manufacturing synthetic resins, can be produced from glucose in fermentation by Rhizopus oryzae. However, the fumaric acid yield is limited by the co-production of ethanol and other byproducts. To increase fumaric acid production, ove...

  1. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... surrounded with explosive mixtures of Pittsburgh natural gas 1 and air. A sufficient number of tests of each... for practical purposes Pittsburgh natural gas (containing a high percentage of methane) is a... adequate, may be used to obtain a firm seat for the glass but not elsewhere. Rubber, putty, and plaster...

  2. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... surrounded with explosive mixtures of Pittsburgh natural gas 1 and air. A sufficient number of tests of each... for practical purposes Pittsburgh natural gas (containing a high percentage of methane) is a... adequate, may be used to obtain a firm seat for the glass but not elsewhere. Rubber, putty, and plaster...

  3. 49 CFR 177.840 - Class 2 (gases) materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... limited to private and contract carriage and to direct movement from point of origin to destination. (b..., the qualified person attending the unloading operation must remain within 45.72 meters (150 feet) of the cargo tank and 7.62 meters (25 feet) of the delivery hose and must observe both the cargo tank...

  4. Building the Class 2 CRISPR-Cas Arsenal.

    PubMed

    Lewis, Kevin M; Ke, Ailong

    2017-02-02

    Adaptation of CRISPR-Cas9 for genome-editing applications has revolutionized biomedical research. New single-component effector CRISPR systems are emerging from the bioinformatics pipeline. How can we best harness their power? Three new studies will no doubt facilitate this transition by generating the C2c1 and C2c2 structure snapshots in different functional states.

  5. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... surrounded with explosive mixtures of Pittsburgh natural gas 1 and air. A sufficient number of tests of each... for practical purposes Pittsburgh natural gas (containing a high percentage of methane) is a... adequate, may be used to obtain a firm seat for the glass but not elsewhere. Rubber, putty, and plaster...

  6. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... surrounded with explosive mixtures of Pittsburgh natural gas 1 and air. A sufficient number of tests of each... for practical purposes Pittsburgh natural gas (containing a high percentage of methane) is a satisfactory substitute for pure methane. (3) Glass-enclosed parts of such compartments must be guarded and...

  7. 49 CFR 177.840 - Class 2 (gases) materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... record of the cargo tank pressure and ambient (outside) temperature: (1) At the start of each trip, (2... temperature and pressure of the liquid must be reduced by a manually controlled release of vapor; and (2) The... unloading to assure that they are of sound quality, without obvious defects detectable through...

  8. 49 CFR 177.840 - Class 2 (gases) materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... record of the cargo tank pressure and ambient (outside) temperature: (1) At the start of each trip, (2... temperature and pressure of the liquid must be reduced by a manually controlled release of vapor; and (2) The... unloading to assure that they are of sound quality, without obvious defects detectable through...

  9. 49 CFR 177.840 - Class 2 (gases) materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... record of the cargo tank pressure and ambient (outside) temperature: (1) At the start of each trip, (2... temperature and pressure of the liquid must be reduced by a manually controlled release of vapor; and (2) The... unloading to assure that they are of sound quality, without obvious defects detectable through...

  10. 49 CFR 177.840 - Class 2 (gases) materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., the driver shall make a written record of the cargo tank pressure and ambient (outside) temperature... performed and verified as follows: (1) The temperature and pressure of the liquid must be reduced by a... sound quality, without obvious defects detectable through visual observation and audio awareness,...

  11. Water Mist Fire Tests For Class 2 & 3 Engine Rooms

    DTIC Science & Technology

    2007-11-02

    system, the fire-test-procedure working group at FP39 focused on water mist systems. Only limited data(3) were available to the working group on water...sources described in Table 2. The working group initially felt that, given the limited testing experience, a protocol was appropriate for spaces 10 m x 10...greater than 5 m, no data were available to the working group at FP39. (Note that Class II engine rooms are between 500 m3 and 3000 M3 in volume, while

  12. 30 CFR 20.9 - Class 2 lamps.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... prevent unauthorized and unsafe opening of the compartments in a mine. (c) Locks or seals (battery). The battery shall be enclosed in a locked or sealed container that will prevent exposure of live terminals. (d) Temperature of lamp. The temperature of the lamp under conditions of use shall not be such that a person...

  13. Aviation Structural Mechanic, Second Class, 2-13. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This self-paced, individualized course, adapted from military curriculum materials for use in vocational and technical education, teaches students the skills needed to become aviation structural mechanics (second class). The course materials consist of five pamphlets covering the structural maintenance and repair of aircraft. The first pamphlet…

  14. The Association of HLA Class 1 and Class 2 Antigens with Multiple Myeloma in Iranian Patients.

    PubMed

    Sayad, Arezou; Akbari, Mohammad Taghi; Mehdizadeh, Mahshid; Roshandel, Elham; Abedinpour, Soheila; Hajifathali, Abbas

    2014-12-05

    Amaç: Multiple myeloma (MM), malign plazma hürelerinin klonal çoğalması ile karakterize bir B hücre neoplazisidir. Çeşitli çalışmaların sonuçlarına göre, bazı sınıf 1 ve 2 HLA genlerinin hastalığa yatkınlık sağladığına dair görüşler ortaya atılmıştır. Farklı popülasyonlarda yapılan çalışmalarda, farklı HLA sınıf 1 ve 2 allellerinin MM üzerine etkisi olduğu bildirilmiştir. Bu çalışmada, İranlı MM hastalarında HLA sınıf 1 ve sınıf 2 antijenlerinin birlikteliğini değerlendirdik. Gereç ve Yöntemler: HLA-Ready Gene ABDR kitleriyle tekli spesifik primer polimeraz zincir reaksiyonu yönteminin kullanıldığı bu olgu-kontrol genetiplendirme çalışmasında, hasta grubuna Taleghani Hastanesi kemik iliği nakli bölümünden seçilen 105 İranlı MM hastası ve 150 de kontrol olgusu dahil edilmiştir.Bulgular: Çalışma sonucunda, HLA-A*03 hasta grubunda %21 ve kontrol grubunda %12 bulunurken, HLA-B*18 ise hasta grubunda %11 ve kontrol grubunda %3 olarak saptanmıştır. MM hastalarının HLA-A*03 ve HLA-B*18 allele sahip olma oranı kontrol olgularıyla karşılaştırıldığında istatistiki olarak anlamlı olacak şekilde yüksek bulunmuştur (p=0,039, OR=2,057 ve p=0,013, OR=3,567, sırasıyla). Sonuç: Bizim bulgularımız, İran toplumunda HLA-A*03 ve HLA-B*18 allel varlığının istatistiki olarak anlamlı olacak şekilde MM’ye yatkınlık yarattığını ortaya koymaktadır. Bununla birlikte, diğer toplumlara bakıldığında adı geçen allellerin aynı sonucu doğurmadıkları görülmektedir. Farklı etnik gruplar arasındaki bu birlikteliği değerlendiren fazla sayıda çalışma olmadığı için, gelecek dönemlerde MM’li hastalarda HLA genlerinin birlikteliğinin sonuçlarını izah edebilecek daha ayrıntılı çalışmalara gereksinim vardır.

  15. Aviation Structural Mechanic, First Class, 2-12. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This self-paced, individualized course, adapted from military curriculum materials for use in vocational and technical education, teaches students the skills needed to become aviation structural mechanics (first class). The course materials consist of three pamphlets. The first pamphlet covers aircraft maintenance management, records, and reports…

  16. Treatment of class 2 division 1 malocclusion with severe short roots of upper central incisors

    PubMed Central

    Chandrasekar, Ramaswamy; Sridevi, Kondety Sambamoorthy

    2013-01-01

    The average amount of resorption per root of examined maxillary incisors or anterior teeth is < 1.5 mm during comprehensive orthodontic treatment. About 5% of adults and 2% of adolescents are likely to have at least one tooth with resorption of more than 5 mm during active treatment. Although resorption stops once the active appliances are removed, fortunately, truly severe resorption that threatens the longevity of the tooth or forces a halt to treatment is rare. The fact is, however that orthodontic tooth movement does directly cause irreversible resorption of the root. As the movers of the teeth, it is incumbent for us to know as much as possible about the causes, effects and prevention of this phenomenon. PMID:23956601

  17. Genome-wide Analysis of Phosphoenolpyruvate Carboxylase Gene Family and Their Response to Abiotic Stresses in Soybean

    PubMed Central

    Wang, Ning; Zhong, Xiujuan; Cong, Yahui; Wang, Tingting; Yang, Songnan; Li, Yan; Gai, Junyi

    2016-01-01

    Phosphoenolpyruvate carboxylase (PEPC) plays an important role in assimilating atmospheric CO2 during C4 and crassulacean acid metabolism photosynthesis, and also participates in various non-photosynthetic processes, including fruit ripening, stomatal opening, supporting carbon–nitrogen interactions, seed formation and germination, and regulation of plant tolerance to stresses. However, a comprehensive analysis of PEPC family in Glycine max has not been reported. Here, a total of ten PEPC genes were identified in soybean and denominated as GmPEPC1-GmPEPC10. Based on the phylogenetic analysis of the PEPC proteins from 13 higher plant species including soybean, PEPC family could be classified into two subfamilies, which was further supported by analyses of their conserved motifs and gene structures. Nineteen cis-regulatory elements related to phytohormones, abiotic and biotic stresses were identified in the promoter regions of GmPEPC genes, indicating their roles in soybean development and stress responses. GmPEPC genes were expressed in various soybean tissues and most of them responded to the exogenously applied phytohormones. GmPEPC6, GmPEPC8 and GmPEPC9 were significantly induced by aluminum toxicity, cold, osmotic and salt stresses. In addition, the enzyme activities of soybean PEPCs were also up-regulated by these treatments, suggesting their potential roles in soybean response to abiotic stresses. PMID:27924923

  18. Improved oil recovery in Mississippian carbonate reservoirs of Kansas -- near term -- Class 2. Quarterly report, April 1--June 30, 1995

    SciTech Connect

    Carr, T.; Green, D.W.; Willhite, G.P.; Schoeling, L.; Reynolds, R.

    1995-07-01

    The objective of this project is to demonstrate incremental reserves from Osagian and Meramecian (Mississippian) dolomite reservoirs in western Kansas through application of reservoir characterization to identify areas of unrecovered mobile oil. The project addresses producibility problems in two fields: specific reservoirs target the Schaben Field in Ness County, Kansas, and the Bindley Field in Hodgeman County, Kansas. The producibility problems to be addressed include inadequate reservoir characterization, drilling and completion design problems, non-optimum recovery efficiency. The results of this project will be disseminated through various technology transfer activities. General overview--progress is reported for the period from 1 April 1995 to 30 June 1995. Work in this quarter has concentrated on reservoir characterization with the initiation of technology transfer. Difficulties still remain in the drilling of the final two wells. Some preliminary work on reservoir characterization has been completed, and related technology transfer has been initiated.

  19. In vitro-in vivo correlation of the effect of supersaturation on the intestinal absorption of BCS Class 2 drugs.

    PubMed

    Higashino, Haruki; Hasegawa, Tsubasa; Yamamoto, Mari; Matsui, Rie; Masaoka, Yoshie; Kataoka, Makoto; Sakuma, Shinji; Yamashita, Shinji

    2014-03-03

    The aim of this study was to establish an in vitro method for evaluating the effect of supersaturation on oral absorption of poorly water-soluble drugs in vivo. Albendazole, dipyridamole, gefitinib, and ketoconazole were used as model drugs. Supersaturation of each drug was induced by diluting its stock solution by fasted state simulated intestinal fluid (FaSSIF) (solvent-shift method), then dissolution and precipitation profile of the drug was observed in vitro. The crystalline form of the precipitate was checked by differential scanning calorimetry (DSC). For comparison, control suspension was prepared by suspending a drug powder directly into FaSSIF (powder-suspending method). In vivo intestinal absorption of the drug was observed in rats by determined the plasma concentration after intraduodenal administration of drug suspensions. For all drugs, suspensions prepared by solvent-shift method showed significantly higher dissolved concentration in vitro than that prepared by powder-suspending method, clearly indicated the induction of supersaturation. DSC analysis revealed that crystalline form of the precipitate profoundly affects the extent and the duration of supersaturation. A rat in vivo study confirmed that the supersaturation of these drugs increased the fraction absorbed from the intestine, which corresponded well to the in vitro dissolution and precipitation profile of drugs except for ketoconazole. For ketoconazole, an in vivo absorption study was performed in rats pretreated with 1-aminobenzotriazole, a potent inhibitor of CYP mediated metabolism. CYP inhibition study suggested that the high luminal concentration of ketoconazole caused by supersaturation saturated the metabolic enzymes and further increased the systemic exposure of the absorbed drug. The additional effects of supersaturation on the absorption of ketoconazole are consistent with previous studies in humans under differing gastric pH conditions. In conclusion, effects of supersaturation on the intestinal absorption of poorly water-soluble drugs could be predicted from in vitro dissolution and a precipitation study. However if supersaturation affects the pharmacokinetic profiles of drugs, such as a first-pass metabolism, a combination with in vivo study should be required to evaluate its impact on oral bioavailability.

  20. Jasmonic acid is a downstream component in the modulation of somatic embryogenesis by Arabidopsis Class 2 phytoglobin

    PubMed Central

    Mira, Mohamed M.; Wally, Owen S. D.; Elhiti, Mohamed; El-Shanshory, Adel; Reddy, Dhadi S.; Hill, Robert D.; Stasolla, Claudio

    2016-01-01

    Previous studies have shown that the beneficial effect of suppression of the Arabidopsis phytoglobin 2 gene, PGB2, on somatic embryogenesis occurs through the accumulation of nitric oxide (NO) within the embryogenic cells originating from the cultured explant. NO activates the expression of Allene oxide synthase (AOS) and Lipoxygenase 2 (LOX2), genes encoding two key enzymes of the jasmonic acid (JA) biosynthetic pathway, elevating JA content within the embryogenic tissue. The number of embryos in the single aos1-1 mutant and pgb2-aos1-1 double mutant declined, and was not rescued by increasing levels of NO stimulating embryogenesis in wild-type tissue. NO also influenced JA responses by up-regulating PLANT DEFENSIN 1 (PDF1) and JASMONATE-ZIM-PROTEIN (JAZ1), as well as down-regulating MYC2. The NO and JA modulation of MYC2 and JAZ1 controlled embryogenesis. Ectopic expression of JAZ1 or suppression of MYC2 promoted the formation of somatic embryos, while repression of JAZ1 and up-regulation of MYC2 reduced the embryogenic performance. Sustained expression of JAZ1 induced the transcription of several indole acetic acid (IAA) biosynthetic genes, resulting in higher IAA levels in the embryogenic cells. Collectively these data fit a model integrating JA in the PGB2 regulation of Arabidopsis embryogenesis. Suppression of PGB2 increases JA through NO. Elevated levels of JA repress MYC2 and induce JAZ1, favoring the accumulation of IAA in the explants and the subsequent production of somatic embryos. PMID:26962208

  1. 49 CFR 173.115 - Class 2, Divisions 2.1, 2.2, and 2.3-Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... kPa (14.7 psia)) which— (1) Is ignitable at 101.3 kPa (14.7 psia) when in a mixture of 13 percent or... cryogenic gas, compressed gas in solution, asphyxiant gas and oxidizing gas). For the purpose of this subchapter, a non-flammable, nonpoisonous compressed gas (Division 2.2) means any material (or mixture)...

  2. 49 CFR 173.115 - Class 2, Divisions 2.1, 2.2, and 2.3-Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... kPa (14.7 psia)) which— (1) Is ignitable at 101.3 kPa (14.7 psia) when in a mixture of 13 percent or... cryogenic gas, compressed gas in solution, asphyxiant gas and oxidizing gas). For the purpose of this subchapter, a non-flammable, nonpoisonous compressed gas (Division 2.2) means any material (or mixture)...

  3. 49 CFR 173.115 - Class 2, Divisions 2.1, 2.2, and 2.3-Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... kPa (14.7 psia) of pressure (a material which has a boiling point of 20 °C (68 °F) or less at 101.3... pressure of 101.3 kPa (14.7 psia) (a material which has a boiling point of 20 °C (68 °F) or less at 101.3 k... gas having a boiling point colder than -−90 °C (−130 °F) at 101.3 kPa (14.7 psia) absolute. A...

  4. 49 CFR 173.115 - Class 2, Divisions 2.1, 2.2, and 2.3-Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... kPa (14.7 psia) of pressure (a material which has a boiling point of 20 °C (68 °F) or less at 101.3... pressure of 101.3 kPa (14.7 psia) (a material which has a boiling point of 20 °C (68 °F) or less at 101.3 k... gas having a boiling point colder than -−90 °C (−130 °F) at 101.3 kPa (14.7 psia) absolute. A...

  5. 49 CFR 173.115 - Class 2, Divisions 2.1, 2.2, and 2.3-Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... kPa (14.7 psia) of pressure (a material which has a boiling point of 20 °C (68 °F) or less at 101.3... pressure of 101.3 kPa (14.7 psia) (a material which has a boiling point of 20 °C (68 °F) or less at 101.3 k... gas having a boiling point colder than -−90 °C (−130 °F) at 101.3 kPa (14.7 psia) absolute. A...

  6. A Comparison of Arch Width with Angle Classification and Wits Appraisal in Class 2 Division 1 and Class 1 Individuals.

    DTIC Science & Technology

    1983-05-01

    Statistical analysis of the mandibular plane angle, a cephalometric skeletal measure of vertical relationships, revealed no significant differences among the... cephalometrically . 5) to determine, by correlation, what associations may exist among the sagittal, vertical and width measurements. 6) to determine sex differences...mechanism helped guide the teeth into occlusion. No measurements were made to determine if anteroposterior or vertical dimensions were correlated to

  7. [Functions of plant phosphoenolpyruvate carboxylase and its applications for genetic engineering].

    PubMed

    Wei, Shaowei; Li, Yin

    2011-12-01

    Phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) is an important ubiquitous cytosol enzyme that fixes HCO3 together with phosphoenolpyruvate (PEP) and yields oxaloacetate that can be converted to intermediates of the citric acid cycle. In plant cells, PEPC participates in CO2 assimilation and other important metabolic pathways, and it has broad functions in different plant tissues. PEPC is also involved in the regulation of storage product synthesis and metabolism in seeds, such as affecting the metabolic fluxes from sugars/starch towards the synthesis of fatty acids or amino acids and proteins. In this review, we introduced the progress in classification, structure and regulation of PEPC in plant tissues. We discussed the potential applications of plant PEPCs in genetic engineering. The researches in functions and regulation mechanism of plant PEPCs will provide beneficial approaches to applications of plant PEPCs in high-yield crops breeding, energy crop and microbe genetic engineering.

  8. Nitrogen-Dependent Carbon Fixation by Picoplankton In Culture and in the Mississippi River

    SciTech Connect

    Aubrey Smith; Marguerite W. Coomes; Thomas E. Smith

    2005-04-30

    The pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC), of the marine cyanobacterium Synechococcus PCC 7002, was isolated and sequenced. PEPC is an anaplerotic enzyme, but it may also contribute to overall CO2 fixation through β-carboxylation reactions. A consensus sequence generated by aligning the pepc genes of Anabaena variabilis, Anacystis nidulans and Synechocystis PCC 6803 was used to design two sets of primers that were used to amplify segments of Synechococcus PCC 7002 pepc. In order to isolate the gene, the sequence of the PCR product was used to search for the pepc nucleotide sequence from the publicly available genome of Synechococcus PCC 7002. At the time, the genome for this organism had not been completed although sequences of a significant number of its fragments are available in public databases. Thus, the major challenge was to find the pepc gene among those fragments and to complete gaps as necessary. Even though the search did not yield the complete gene, PCR primers were designed to amplify a DNA fragment using a high fidelity thermostable DNA polymerase. An open reading frame (ORF) consisting of 2988 base pairs coding for 995 amino acids was found in the 3066 bp PCR product. The pepc gene had a GC content of 52% and the deduced protein had a calculated molecular mass of 114,049 Da. The amino acid sequence was closely related to that of PEPC from other cyanobacteria, exhibiting 59-61% identity. The sequence differed significantly from plant and E. coli PEPC with only 30% homology. However, comparing the Synechococcus PCC 7002 sequence to the recently resolved E. coli PEPC revealed that most of the essential domains and amino acids involved in PEPC activity were shared by both proteins. The recombinant Synechococcus PCC 7002 PEPC was expressed in E. coli.

  9. Direct and selective small-molecule inhibition of photosynthetic PEP carboxylase: New approach to combat C4 weeds in arable crops.

    PubMed

    Paulus, Judith Katharina; Förster, Kerstin; Groth, Georg

    2014-06-05

    Phosphoenolpyruvate carboxylase (PEPC) is a key enzyme of C4 photosynthesis. Besides, non-photosynthetic isoforms of PEPC are found in bacteria and all types of plants, although not in animals or fungi. A single residue in the allosteric feedback inhibitor site of PEPC was shown to adjust the affinity of the photosynthetic and non-photosynthetic isoforms for feedback inhibition by metabolites of the C4 pathway. Here, we applied computational screening and biochemical analyses to identify molecules that selectively inhibit C4 PEPC, but have no effect on the activity of non-photosynthetic PEPCs. We found two types of selective inhibitors, catechins and quinoxalines. Binding constants in the lower μM range and a strong preference for C4 PEPC qualify the quinoxaline compounds as potential selective herbicides to combat C4 weeds.

  10. Characterization of lysine acetylation of a phosphoenolpyruvate carboxylase involved in glutamate overproduction in Corynebacterium glutamicum.

    PubMed

    Nagano-Shoji, Megumi; Hamamoto, Yuma; Mizuno, Yuta; Yamada, Ayuka; Kikuchi, Masaki; Shirouzu, Mikako; Umehara, Takashi; Yoshida, Minoru; Nishiyama, Makoto; Kosono, Saori

    2017-03-03

    Protein Nε-acylation is emerging as a ubiquitous post-translational modification. In Corynebacterium glutamicum, which is utilized for industrial production of L-glutamate, the levels of protein acetylation and succinylation change drastically under the conditions that induce glutamate overproduction. Here, we characterized the acylation of phosphoenolpyruvate carboxylase (PEPC), an anaplerotic enzyme that supplies oxaloacetate for glutamate overproduction. We showed that acetylation of PEPC at lysine 653 decreased enzymatic activity, leading to reduced glutamate production. An acetylation-mimic (KQ) mutant of K653 showed severely reduced glutamate production, while the corresponding KR mutant showed normal production levels. Using an acetyllysine-incorporated PEPC protein, we verified that K653-acetylation negatively regulates PEPC activity. In addition, NCgl0616, a sirtuin-type deacetylase, deacetylated K653-acetylated PEPC in vitro. Interestingly, the specific activity of PEPC was increased during glutamate overproduction, which was blocked by the K653R mutation or deletion of sirtuin-type deacetylase homologues. These findings suggested that deacetylation of K653 by NCgl0616 likely plays a role in the activation of PEPC, which maintains carbon flux under glutamate-producing conditions. PEPC deletion increased protein acetylation levels in cells under glutamate-producing conditions, supporting our hypothesis that PEPC is responsible for a large carbon flux change under glutamate-producing conditions. This article is protected by copyright. All rights reserved.

  11. Allosteric Inhibition of Phosphoenolpyruvate Carboxylases is Determined by a Single Amino Acid Residue in Cyanobacteria

    PubMed Central

    Takeya, Masahiro; Hirai, Masami Yokota; Osanai, Takashi

    2017-01-01

    Phosphoenolpyruvate carboxylase (PEPC) is an important enzyme for CO2 fixation and primary metabolism in photosynthetic organisms including cyanobacteria. The kinetics and allosteric regulation of PEPCs have been studied in many organisms, but the biochemical properties of PEPC in the unicellular, non-nitrogen-fixing cyanobacterium Synechocystis sp. PCC 6803 have not been clarified. In this study, biochemical analysis revealed that the optimum pH and temperature of Synechocystis 6803 PEPC proteins were 7.3 and 30 °C, respectively. Synechocystis 6803 PEPC was found to be tolerant to allosteric inhibition by several metabolic effectors such as malate, aspartate, and fumarate compared with other cyanobacterial PEPCs. Comparative sequence and biochemical analysis showed that substitution of the glutamate residue at position 954 with lysine altered the enzyme so that it was inhibited by malate, aspartate, and fumarate. PEPC of the nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120 was purified, and its activity was inhibited in the presence of malate. Substitution of the lysine at position 946 (equivalent to position 954 in Synechocystis 6803) with glutamate made Anabaena 7120 PEPC tolerant to malate. These results demonstrate that the allosteric regulation of PEPC in cyanobacteria is determined by a single amino acid residue, a characteristic that is conserved in different orders. PMID:28117365

  12. Phytochrome-controlled phototropism of protonemata of the moss ceratodon purpureus: physiology of the wild type and class 2 ptr-mutants

    PubMed

    Esch; Hartmann; Cove; Wada; Lamparter

    1999-09-01

    Phototropism and polarotropism in protonemata of the moss Ceratodon purpureus are controlled by the photoreceptor phytochrome. One class of phototropism mutants is characterised by growing randomly when kept for a prolonged time (5 d or longer) in unilateral red light. It was found that a subclass of these mutants grows faster than the wild type, the rate of cell division and the length of the cells being increased. This difference is found for light-grown and dark-grown filaments. It is therefore suggested that the mutant phenotype neither results from a defect in phytochrome photoconversion nor from a defect in phytochrome-gradient formation. Instead, it is possible that a factor which is involved in both signal transduction of phototropism and regulation of cell size and cell division is deregulated. If dark-grown mutant filaments are phototropically stimulated for 24 h, they show a weak phototropic response. Phototropism and polarotropism fluence-rate effect curves for mutants were flattened and shifted to higher fluence rates compared with those for the wild type. With wild-type filaments, a previously unreported response was observed. At a low fluence rate, half of the filaments grew positively phototropically, while the other half grew negatively phototropically. It seems that under these conditions, a phytochrome gradient with two maxima for the far-red-absorbing form of phytochrome (Pfr) within the cross-section of the cell is displayed by the response of the filaments. At higher fluence rates, all filaments of the wild type grew towards the light. These data and results from microbeam irradiation experiments and from phototropism studies with filaments growing within agar, indicate that light refraction plays an important role in the formation of the Pfr gradient in phototropism of Ceratodon.

  13. Estimating the upper limit of gas production from Class 2 hydrate accumulations in the permafrost: 2. Alternative well designs and sensitivity analysis

    SciTech Connect

    Moridis, G.; Reagan, M.T.

    2011-01-15

    In the second paper of this series, we evaluate two additional well designs for production from permafrost-associated (PA) hydrate deposits. Both designs are within the capabilities of conventional technology. We determine that large volumes of gas can be produced at high rates (several MMSCFD) for long times using either well design. The production approach involves initial fluid withdrawal from the water zone underneath the hydrate-bearing layer (HBL). The production process follows a cyclical pattern, with each cycle composed of two stages: a long stage (months to years) of increasing gas production and decreasing water production, and a short stage (days to weeks) that involves destruction of the secondary hydrate (mainly through warm water injection) that evolves during the first stage, and is followed by a reduction in the fluid withdrawal rate. A well configuration with completion throughout the HBL leads to high production rates, but also the creation of a secondary hydrate barrier around the well that needs to be destroyed regularly by water injection. However, a configuration that initially involves heating of the outer surface of the wellbore and later continuous injection of warm water at low rates (Case C) appears to deliver optimum performance over the period it takes for the exhaustion of the hydrate deposit. Using Case C as the standard, we determine that gas production from PA hydrate deposits increases with the fluid withdrawal rate, the initial hydrate saturation and temperature, and with the formation permeability.

  14. Improved oil recovery in Mississippian carbonate reservoirs of Kansas -- Near term -- Class 2. Annual report, September 18, 1994--October 1, 1995

    SciTech Connect

    Carr, T.R.; Green, D.W.; Willhite, G.P.

    1996-08-01

    This report represents a summary of the progress during the first year of Budget period 1 of the project. Two examples of advanced technologies developed as part of this project are highlighted along with the use of the Internet to transfer these technologies. The two advanced technologies are a spread-sheet petrophysical analysis and reservoir evaluation (PfEFFER), and a petrophysical/seismic approach to well logs (pseudoseismic). Work continues on multi-disciplinary reservoir characterization at the demonstration site. The potential for incremental primary recovery is being evaluated using the improved reservoir characterization to target infill drilling and evaluate the potential of a horizontal well. The impact of demonstrating additional incremental primary recovery from sub-Pennsylvanian unconformity Mississippian reservoirs would be significant for Kansas and the US.

  15. Improved oil recovery in Mississippian carbonate reservoirs of Kansas - near term -- Class 2. Quarterly progress report, July 1, 1995--September 30, 1995

    SciTech Connect

    Carr, T.; Green, D.W.; Willhite, G.P.

    1995-11-01

    The objective of this project is to demonstrate incremental reserves from Osagian and Meramecian dolomite reservoirs in western Kansas through application of reservoir characterization to identify areas of unrecovered mobile petroleum. Specific reservoirs targeted are the Schaben Field in Ness County and the Bindley Field in Hodgeman County.

  16. Transgene silencing of sucrose synthase in alfalfa (Medicago sativa L.) stem vascular tissue suggests a role for invertase in cell wall cellulose synthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) plants were transformed with two constructs: (1) a truncated phosphoenolpyruvate carboxylase promoter isolated from alfalfa nodules (PEPC-4) fused to GUS; and (2) PEPC-4 fused with sucrose synthase (SUS) isolated from alfalfa nodules. Histochemical staining for GUS in st...

  17. In vivo phosphorylation of phosphoenolpyruvate carboxylase in Egeria densa, a submersed aquatic species.

    PubMed

    Lara, M V; Casati, P; Andreo, C S

    2001-04-01

    In vivo phosphorylation of PEPC in Egeria densa was studied using plants at high temperature and in light, and plants kept at low temperature and in light. The isoform induced by high temperature and light was more phosphorylated in the light. Changes in kinetic and regulatory properties correlated with changes in the phosphorylation state of PEPC.

  18. (Guard cell biochemistry: Response to environmental stimuli causing changes in gas exchange): Progress report and introduction to experimental rationale and methodology

    SciTech Connect

    Not Available

    1987-01-01

    Procedures are described for microbiochemistry of individual guard cells. Specifically, studies are described for the determination of phosphoenolpyruvate carboxylase (PEPC) in single cells, electrophoresis of the protein complement of small number of cells, the cellular location of abscisic acid, measurement of the photosynthetically driven electron transport in guard cells, and the role of malate in regulation of PEPC. 19 figs., 1 tab. (DT)

  19. Induction of a C(4)-like mechanism of CO(2) fixation in Egeria densa, a submersed aquatic species.

    PubMed

    Casati, P; Lara, M V; Andreo, C S

    2000-08-01

    The expression of phosphoenolpyruvate carboxylase (PEPC) and NADP-malic enzyme (NADP-ME) in Egeria densa leaves was studied under low temperature and light (LTL) following incubation under high temperature and light (HTL), conditions previously shown to induce high and low CO(2) compensation points, respectively. Transfer from LTL to HTL conditions induced increases in the activities and amounts of both enzymes. One NADP-ME isoform was observed in induced and uninduced samples. Two isoforms of PEPC were expressed, with the lower M(r) isoform being induced by HTL. NADP-ME showed properties similar to those of the isoform in C(3) species. The inducible PEPC isoform has a low K(m) for both substrates. PEPC kinetic and regulatory properties (V(max) and K(m) for phosphoenolpyruvate, and I(50) for L-malate) are different in samples taken in the dark from those in the light, indicating that some modification of PEPC may be occurring during the day. Finally, abscisic acid induced the expression of PEPC and NADP-ME in a manner similar to temperature induction, except that the activities of both PEPC isoforms were increased. A different signaling system may exist in this species in response to high temperature or abscisic acid, both of which induce changes in photosynthetic metabolism.

  20. Induction of a C4-Like Mechanism of CO2 Fixation in Egeria densa, a Submersed Aquatic Species1

    PubMed Central

    Casati, Paula; Lara, María V.; Andreo, Carlos S.

    2000-01-01

    The expression of phosphoenolpyruvate carboxylase (PEPC) and NADP-malic enzyme (NADP-ME) in Egeria densa leaves was studied under low temperature and light (LTL) following incubation under high temperature and light (HTL), conditions previously shown to induce high and low CO2 compensation points, respectively. Transfer from LTL to HTL conditions induced increases in the activities and amounts of both enzymes. One NADP-ME isoform was observed in induced and uninduced samples. Two isoforms of PEPC were expressed, with the lower Mr isoform being induced by HTL. NADP-ME showed properties similar to those of the isoform in C3 species. The inducible PEPC isoform has a low Km for both substrates. PEPC kinetic and regulatory properties (Vmax and Km for phosphoenolpyruvate, and I50 for l-malate) are different in samples taken in the dark from those in the light, indicating that some modification of PEPC may be occurring during the day. Finally, abscisic acid induced the expression of PEPC and NADP-ME in a manner similar to temperature induction, except that the activities of both PEPC isoforms were increased. A different signaling system may exist in this species in response to high temperature or abscisic acid, both of which induce changes in photosynthetic metabolism. PMID:10938377

  1. 78 FR 19733 - Draft General Management Plan and Draft Environmental Impact Statement, Fort Raleigh National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ..., Environment, and Public Comment (PEPC) Web site: http://parkplanning.nps.gov/FORA and media outlets. ADDRESSES... our research on the site's history, archeology, inhabitants and events with emphasis on...

  2. In vivo monoubiquitination of anaplerotic phosphoenolpyruvate carboxylase occurs at Lys624 in germinating sorghum seeds

    PubMed Central

    Echevarría, Cristina

    2014-01-01

    Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) is an important cytosolic regulatory enzyme that plays a pivotal role in numerous physiological processes in plants, including seed development and germination. Previous studies demonstrated the occurrence of immunoreactive PEPC polypeptides of ~110kDa and 107kDa (p110 and p107, respectively) on immunoblots of clarified extracts of germinating sorghum (Sorghum bicolor) seeds. In order to establish the biochemical basis for this observation, a 460kDa PEPC heterotetramer composed of an equivalent ratio of p110 and p107 subunits was purified to near homogeneity from the germinated seeds. Mass spectrometry established that p110 and p107 are both encoded by the same plant-type PEPC gene (CP21), but that p107 was in vivo monoubiquitinated at Lys624 to form p110. This residue is absolutely conserved in vascular plant PEPCs and is proximal to a PEP-binding/catalytic domain. Anti-ubiquitin IgG immunodetected p110 but not p107, whereas incubation with a deubiquitinating enzyme (USP-2 core) efficiently converted p110 into p107, while relieving the enzyme’s feedback inhibition by l-malate. Partial PEPC monoubiquitination was also detected during sorghum seed development. It is apparent that monoubiquitination at Lys624 is opposed to phosphorylation at Ser7 in terms of regulating the catalytic activity of sorghum seed PEPC. PEPC monoubiquitination is hypothesized to fine-tune anaplerotic carbon flux according to the cell’s immediate physiological requirements for tricarboxylic acid cycle intermediates needed in support of biosynthesis and carbon–nitrogen interactions. PMID:24288181

  3. Light Modulation of Maize Leaf Phosphoenolpyruvate Carboxylase 1

    PubMed Central

    Huber, Steven C.; Sugiyama, Tatsuo; Akazawa, Takashi

    1986-01-01

    Phosphoenolpyruvate carboxylase (PEPC) was extracted from maize (Zea mays L. cv Golden Cross Bantam T51) leaves harvested in the dark or light and was partially purified by (NH4)2SO4 fractionation and gel filtration to yield preparations that were 80% homogeneous. Malate sensitivity, PEPC activity, and PEPC protein (measured immunochemically) were monitored during purification. As reported previously, PEPC from dark leaves was more sensitive to malate inhibition compared to enzyme extracted from light leaves. Extraction and purification in the presence of malate stabilized the characteristics of the two forms. During gel filtration on Sephacryl S-300, all of the PEPC activity and PEPC protein emerged in a single high molecular weight peak, indicating that no inactive dissociated forms (dimers, monomers) were present. However, there was a slight difference between the light and dark enzymes in elution volume during gel filtration. In addition, specific activity (units at pH 7/milligram PEPC protein) decreased through the peak for both enzyme samples; because the dark enzyme emerged at a slightly higher elution volume, it contained enzyme with a relatively lower specific activity. The variation in specific activity of the dark enzyme corresponded with changes in malate sensitivity. Immunoblotting of samples with different specific activity and malate sensitivity, obtained from gel filtration, revealed only a single polypeptide with a relative molecular mass of 100,000. When the enzyme was extracted and purified in the absence of malate, characteristic differences of the light and dark enzymes were lost, the enzymes eluted at the same volume during gel filtration, and specific activity was constant through the peak. We conclude that maize leaf PEPC exists in situ as a tetramer of a single polypeptide and that subtle conformation changes can affect both enzymic activity and sensitivity to malate inhibition. Images Fig. 6 PMID:16665065

  4. Pulsed Power Aspects of the NIF Plasma Electrode Pockels Cell

    SciTech Connect

    Arnold, P A; Ollis, C W; Hinz, A F; Barbosa, F; Fulkerson, E S

    2005-06-09

    The Plasma Electrode Pockels Cell (PEPC) embodies technology essential to the National Ignition Facility (NIF). Together with a thin-film polarizer, PEPC functions as an optical switch for the main amplifier cavity, allowing optical pulses to be trapped, and then released, and enabling NIF to take advantage of the attendant gain and cost-savings. Details of the genesis, development, and prototyping of the PEPC are well documented. After moving from its laboratory setting to the NIF facility, PEPC--via its performance during the two-year NIF Early Light (NEL) campaign and its ongoing operation during facility build-out--has proven to be a fully functional system. When complete, NIF will accommodate 192 beams, capable of delivering 1.8 MJ to a fusion target. Forty-eight Plasma Electrode Pockels--driven by nearly 300 high-power, high-voltage pulse generators--will support this complement of beams. As deployed, PEPC is a complex association of state-of-the-art optics; low-voltage and high-voltage electronics; and mechanical, gas, and vacuum subsystems--all under computer control. In this paper, we briefly describe each of these elements, but focus on the pulse power aspects of the PEPC system.

  5. Photosynthetic and Other Phosphoenolpyruvate Carboxylase Isoforms in the Single-Cell, Facultative C4 System of Hydrilla verticillata1

    PubMed Central

    Rao, Srinath K.; Magnin, Noël C.; Reiskind, Julia B.; Bowes, George

    2002-01-01

    The submersed monocot Hydrilla verticillata (L.f.) Royle is a facultative C4 plant. It typically exhibits C3 photosynthetic characteristics, but exposure to low [CO2] induces a C4 system in which the C4 and Calvin cycles co-exist in the same cell and the initial fixation in the light is catalyzed by phosphoenolpyruvate carboxylase (PEPC). Three full-length cDNAs encoding PEPC were isolated from H. verticillata, two from leaves and one from root. The sequences were 95% to 99% identical and shared a 75% to 85% similarity with other plant PEPCs. Transcript studies revealed that one isoform, Hvpepc4, was exclusively expressed in leaves during C4 induction. This and enzyme kinetic data were consistent with it being the C4 photosynthesis isoform. However, the C4 signature serine of terrestrial plant C4 isoforms was absent in this and the other H. verticillata sequences. Instead, alanine, typical of C3 sequences, was present. Western analyses of C3 and C4 leaf extracts after anion-exchange chromatography showed similar dominant PEPC-specific bands at 110 kD. In phylogenetic analyses, the sequences grouped with C3, non-graminaceous C4, and Crassulacean acid metabolism PEPCs but not with the graminaceous C4, and formed a clade with a gymnosperm, which is consistent with H. verticillata PEPC predating that of other C4 angiosperms. PMID:12376652

  6. Fractographic and Microstructural Analysis of Stress Corrosion Cracking of A533 Grade B Class 1 Plate and A508 Class 2 Forging in Pressurized Reactor-Grade Water at 93 C.

    DTIC Science & Technology

    1980-01-25

    N UMBER Z.GOVT ACCESSION NO: 3. RECIPIENT’S CATALOG NUMBER NUREG /CR 11277 NRL Memorandum Report 4121 4. TITLE (and Subtitle) S. TYPE OF REPORT...13, No. 2, 1978, pp. 75-78. (81 Cullen, W.H., et al., "Fatigue Crack Growth of A508 Steel in High Temperature, Pressurized, Reactor Grade Water," NUREG

  7. Plasma electrode pockels cell for the National Ignition Facility

    SciTech Connect

    Alger, T.; Biltoft, P.; Boley, C. D.; Fochs, S.; Funkhouser, B.; Rhodes, M. A.

    1998-07-28

    The National Ignition Facility (NIF), now under construction at Lawrence Livermore National Laboratory, will be the largest laser fusion facility ever built. The NIF laser architecture is based on a multi-pass power amplifier to reduce cost and maximize performance. A key component in this laser design is an optical switch that closes to trap the optical pulse in the cavity for four gain passes and then opens to divert the optical pulse out of the amplifier cavity. The switch is comprised of a Pockels cell and a polarizer and is unique because it handles a beam that is 40 cm x 40 cm square and allows close horizontal and vertical beam spacing. Conventional Pockels cells do not scale to such large apertures or the square shape required for close packing. Our switch is based on a Plasma-Electrode Pockels Cell (PEPC). In a PEPC, low-pressure helium discharges (1-2 kA) are formed on both sides of a thin slab of electro-optic material. Typically, we use KH{sub 2}PO{sub 4 } crystals (KDP). The discharges form highly conductive, transparent sheets that allow uniform application of a high-voltage pulse (17 kV) across the crystal. A 37 cm x 37 cm PEPC has been in routine operation for two years on the 6 k.J Beamlet laser at LLNL. For the NIF, a module four apertures high by one wide (4x1) is required. However, this 4x1 mechanical module will be comprised electrically of a pair of 2x1 sub-modules. Last year (FY 97), we demonstrated full operation of a prototype 2x1 PEPC. In this PEPC, the plasma spans two KDP crystals. A major advance in the 2x1 PEPC over the Beamlet PEPC is the use of anodized aluminum construction that still provides sufficient insulation to allow formation of the planar plasmas.

  8. Design and performance of the beamlet optical switch

    SciTech Connect

    Rhodes, M.A.; Woods, B.W.; DeYoreo, J.J.

    1996-06-01

    High-energy lasers for Inertial Confinement Fusion (ICF) experiments are typically designed with large apertures (>30 cm) to keep the fluence below the damage threshold of the various optical components. Until recently, no optical switch technology could be scaled to the aperture size, aperture shape (square), and switching speed required for the next generation of ICF drivers. This step is critical: The Beamlet multipass amplifier cavity uses a full-aperture optical switch to trap the laser pulse within the cavity and to divert the pulse out of the cavity when it reaches the required energy. By rotating the polarization of the beam, a Pockels cell in the switch controls whether the beam is transmitted through, or reflected from, the polarizer. In this article the authors describe an optical switch technology that does scale to the required aperture size and shape for Beamlet and the porposed National Ignition Facility (NIF) laser, and can employ a thin crystal. This switch consists of a thin-film polarizer and a plasma-electrode Pockels cell (PEPC), the latter originally invented at Lawrence Livermore National Laboratory (LLNL) in the 1980s and under further development since 1991. After discussing the PEPC concept, they present the design and optical performance of a 32 x 32 cm{sup 2} prototype PEPC, including discussions of the crystals, the PEPC assembly, the vacuum and gas system, and the high-voltage pulsers. Then they describe the performance of the 37 x 37 cm{sup 2} PEPC construced specifically for the Beamlet laser. Finally, they discuss important technology issues that arose during PEPC development: cathode sputtering, cathode heating, nonuniformities in the switching profile, switch-pulse leakage current, and an estimate of the plasma density and temperature produced during PEPC operation.

  9. Effects of phosphoenolpyruvate carboxylase desensitization on glutamic acid production in Corynebacterium glutamicum ATCC 13032.

    PubMed

    Wada, Masaru; Sawada, Kazunori; Ogura, Kotaro; Shimono, Yuta; Hagiwara, Takuya; Sugimoto, Masakazu; Onuki, Akiko; Yokota, Atsushi

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) in Corynebacterium glutamicum ATCC13032, a glutamic-acid producing actinobacterium, is subject to feedback inhibition by metabolic intermediates such as aspartic acid and 2-oxoglutaric acid, which implies the importance of PEPC in replenishing oxaloacetic acid into the TCA cycle. Here, we investigated the effects of feedback-insensitive PEPC on glutamic acid production. A single amino-acid substitution in PEPC, D299N, was found to relieve the feedback control by aspartic acid, but not by 2-oxoglutaric acid. A simple mutant, strain R1, having the D299N substitution in PEPC was constructed from ATCC 13032 using the double-crossover chromosome replacement technique. Strain R1 produced glutamic acid at a concentration of 31.0 g/L from 100 g/L glucose in a jar fermentor culture under biotin-limited conditions, which was significantly higher than that of the parent, 26.0 g/L (1.19-fold), indicative of the positive effect of desensitized PEPC on glutamic acid production. Another mutant, strain DR1, having both desensitized PEPC and PYK-gene deleted mutations, was constructed in a similar manner using strain D1 with a PYK-gene deleted mutation as the parent. This mutation had been shown to enhance glutamic acid production in our previous study. Although marginal, strain D1 produced higher glutamic acid, 28.8 g/L, than ATCC13032 (1.11-fold). In contrast, glutamic acid production by strain DR-1 was elevated up to 36.9 g/L, which was 1.42-fold higher than ATCC13032 and significantly higher than the other three strains. The results showed a synergistic effect of these two mutations on glutamic acid production in C. glutamicum.

  10. Allele frequencies and genetic diversity in two groups of wild tufted capuchin monkeys (Cebus apella nigritus) living in an urban forest fragment.

    PubMed

    Amaral, Jeanne Margareth Jimenes; Simões, Aguinaldo Luiz; De Jong, David

    2005-12-30

    There have been numerous studies genetically characterizing Old World Primates using microsatellites. However, few studies have been made of New World species and none on free-ranging Cebus apella, even though it is probably the most widely distributed species of monkey in the New World. The paucity of studies is due, in part, to the lack of polymorphisms described for this species. We studied two groups of wild tufted capuchins, Cebus apella nigritus, which inhabit Mata Santa Teresa, the Ecological Reserve of Ribeirão Preto, a 158-ha forest fragment in a semi-urban zone of Ribeirão Preto, SP, Brazil. Group 1 had about 60 animals, 35 of which were sampled, and group 2 had about 40 animals, 20 of which were sampled. These group sizes are much larger than the published reports of 6-30 for this species, despite, or perhaps due to the isolation and the size of the forest fragment. Allele PEPC59*1 was the most frequent of all alleles at all loci in both groups (55.7 and 55%), allele PEPC8*1 was the most common allele in group 2 (46.9%) and PEPC8*4 in group 1 (41.1%), allele PEPC3*2 was the most common in group 1 (35.7%) and allele PEPC3*4 in group 2 (31.6%). The genetic diversity, considering each locus in each group, varied from 61.9% at locus PEPC59 to 78.6% at locus PEPC3, both in group 1. The mean genetic diversity (H(S)), considering both groups for all of the loci, was 71.1%. The inter-group diversity (F(ST)) was 1.9%, indicating that these groups belong to the same population. These groups apparently have a high genetic diversity, despite their isolation in a limited forest fragment, although more data are needed to adequately characterize this population.

  11. Interplay of light and temperature during the in planta modulation of C4 phosphoenolpyruvate carboxylase from the leaves of Amaranthus hypochondriacus L.: diurnal and seasonal effects manifested at molecular levels.

    PubMed

    Avasthi, Uday K; Izui, Katsura; Raghavendra, Agepati S

    2011-01-01

    The interactive effects of light and temperature on C(4) phosphoenolpyruvate carboxylase (PEPC) were examined both in vivo and in situ using the leaves of Amaranthus hypochondriacus collected at different times during a day and in each month during the year. The maximum activity of PEPC, least inhibition by malate, and highest activation by glucose-6-phosphate were at 15.00 h during a typical day, in all the months. This peak was preceded by maximum ambient light but coincided with high temperature in the field. The highest magnitude in such responses was in the summer (e.g. May) and least in the winter (e.g. December). Light appeared to dominate in modulating the PEPC catalytic activity, whereas temperature had a strong influence on the regulatory properties, suggesting interesting molecular interactions. The molecular mechanisms involved in such interactive effects were determined by examining the PEPC protein/phosphorylation/mRNA levels. A marked diurnal rhythm could be seen in the PEPC protein levels and phosphorylation status during May (summer month). In contrast, only the phosphorylation status increased during the day in December (winter month). The mRNA peaks were not as strong as those of phosphorylation. Thus, the phosphorylation status and the protein levels of PEPC were crucial in modulating the daily and seasonal patterns in C(4) leaves in situ. This is the first detailed study on the diurnal as well as seasonal patterns in PEPC activity, its regulatory properties, protein levels, phosphorylation status, and mRNA levels, in relation to light and temperature intensities in the field.

  12. Reciprocal Control of Anaplerotic Phosphoenolpyruvate Carboxylase by in Vivo Monoubiquitination and Phosphorylation in Developing Proteoid Roots of Phosphate-Deficient Harsh Hakea1[W][OA

    PubMed Central

    Shane, Michael W.; Fedosejevs, Eric T.; Plaxton, William C.

    2013-01-01

    Accumulating evidence indicates important functions for phosphoenolpyruvate (PEP) carboxylase (PEPC) in inorganic phosphate (Pi)-starved plants. This includes controlling the production of organic acid anions (malate, citrate) that are excreted in copious amounts by proteoid roots of nonmycorrhizal species such as harsh hakea (Hakea prostrata). This, in turn, enhances the bioavailability of mineral-bound Pi by solubilizing Al3+, Fe3+, and Ca2+ phosphates in the rhizosphere. Harsh hakea thrives in the nutrient-impoverished, ancient soils of southwestern Australia. Proteoid roots from Pi-starved harsh hakea were analyzed over 20 d of development to correlate changes in malate and citrate exudation with PEPC activity, posttranslational modifications (inhibitory monoubiquitination versus activatory phosphorylation), and kinetic/allosteric properties. Immature proteoid roots contained an equivalent ratio of monoubiquitinated 110-kD and phosphorylated 107-kD PEPC polypeptides (p110 and p107, respectively). PEPC purification, immunoblotting, and mass spectrometry indicated that p110 and p107 are subunits of a 430-kD heterotetramer and that they both originate from the same plant-type PEPC gene. Incubation with a deubiquitinating enzyme converted the p110:p107 PEPC heterotetramer of immature proteoid roots into a p107 homotetramer while significantly increasing the enzyme’s activity under suboptimal but physiologically relevant assay conditions. Proteoid root maturation was paralleled by PEPC activation (e.g. reduced Km [PEP] coupled with elevated I50 [malate and Asp] values) via in vivo deubiquitination of p110 to p107, and subsequent phosphorylation of the deubiquitinated subunits. This novel mechanism of posttranslational control is hypothesized to contribute to the massive synthesis and excretion of organic acid anions that dominates the carbon metabolism of the mature proteoid roots. PMID:23407057

  13. Species having C4 single-cell-type photosynthesis in the Chenopodiaceae family evolved a photosynthetic phosphoenolpyruvate carboxylase like that of Kranz-type C4 species.

    PubMed

    Lara, María Valeria; Chuong, Simon D X; Akhani, Hossein; Andreo, Carlos Santiago; Edwards, Gerald E

    2006-10-01

    Spatial and temporal regulation of phosphoenolpyruvate carboxylase (PEPC) is critical to the function of C(4) photosynthesis. The photosynthetic isoform of PEPC in the cytosol of mesophyll cells in Kranz-type C(4) photosynthesis has distinctive kinetic and regulatory properties. Some species in the Chenopodiaceae family perform C(4) photosynthesis without Kranz anatomy by spatial separation of initial fixation of atmospheric CO(2) via PEPC from C(4) acid decarboxylation and CO(2) donation to Rubisco within individual chlorenchyma cells. We studied molecular and functional features of PEPC in two single-cell functioning C(4) species (Bienertia sinuspersici, Suaeda aralocaspica) as compared to Kranz type (Haloxylon persicum, Salsola richteri, Suaeda eltonica) and C(3) (Suaeda linifolia) chenopods. It was found that PEPC from both types of C(4) chenopods displays higher specific activity than that of the C(3) species and shows kinetic and regulatory characteristics similar to those of C(4) species in other families in that they are subject to light/dark regulation by phosphorylation and display differential malate sensitivity. Also, the deduced amino acid sequence from leaf cDNA indicates that the single-cell functioning C(4) species possesses a Kranz-type C(4) isoform with a Ser in the amino terminal. A phylogeny of PEPC shows that isoforms in the two single-cell functioning C(4) species are in a clade with the C(3) and Kranz C(4) Suaeda spp. with high sequence homology. Overall, this study indicates that B. sinuspersici and S. aralocaspica have a C(4)-type PEPC similar to that in Kranz C(4) plants, which likely is required for effective function of C(4) photosynthesis.

  14. Shared origins of a key enzyme during the evolution of C4 and CAM metabolism

    PubMed Central

    Christin, Pascal-Antoine; Arakaki, Monica; Osborne, Colin P.; Bräutigam, Andrea; Sage, Rowan F.; Hibberd, Julian M.; Kelly, Steven; Covshoff, Sarah; Wong, Gane Ka-Shu; Hancock, Lillian; Edwards, Erika J.

    2014-01-01

    CAM and C4 photosynthesis are two key plant adaptations that have evolved independently multiple times, and are especially prevalent in particular groups of plants, including the Caryophyllales. We investigate the origin of photosynthetic PEPC, a key enzyme of both the CAM and C4 pathways. We combine phylogenetic analyses of genes encoding PEPC with analyses of RNA sequence data of Portulaca, the only plants known to perform both CAM and C4 photosynthesis. Three distinct gene lineages encoding PEPC exist in eudicots (namely ppc-1E1, ppc-1E2 and ppc-2), one of which (ppc-1E1) was recurrently recruited for use in both CAM and C4 photosynthesis within the Caryophyllales. This gene is present in multiple copies in the cacti and relatives, including Portulaca. The PEPC involved in the CAM and C4 cycles of Portulaca are encoded by closely related yet distinct genes. The CAM-specific gene is similar to genes from related CAM taxa, suggesting that CAM has evolved before C4 in these species. The similar origin of PEPC and other genes involved in the CAM and C4 cycles highlights the shared early steps of evolutionary trajectories towards CAM and C4, which probably diverged irreversibly only during the optimization of CAM and C4 phenotypes. PMID:24638902

  15. Temperature Responses of C4 Photosynthesis: Biochemical Analysis of Rubisco, Phosphoenolpyruvate Carboxylase, and Carbonic Anhydrase in Setaria viridis1[OPEN

    PubMed Central

    Boyd, Ryan A.; Gandin, Anthony; Cousins, Asaph B.

    2015-01-01

    The photosynthetic assimilation of CO2 in C4 plants is potentially limited by the enzymatic rates of Rubisco, phosphoenolpyruvate carboxylase (PEPc), and carbonic anhydrase (CA). Therefore, the activity and kinetic properties of these enzymes are needed to accurately parameterize C4 biochemical models of leaf CO2 exchange in response to changes in CO2 availability and temperature. There are currently no published temperature responses of both Rubisco carboxylation and oxygenation kinetics from a C4 plant, nor are there known measurements of the temperature dependency of the PEPc Michaelis-Menten constant for its substrate HCO3−, and there is little information on the temperature response of plant CA activity. Here, we used membrane inlet mass spectrometry to measure the temperature responses of Rubisco carboxylation and oxygenation kinetics, PEPc carboxylation kinetics, and the activity and first-order rate constant for the CA hydration reaction from 10°C to 40°C using crude leaf extracts from the C4 plant Setaria viridis. The temperature dependencies of Rubisco, PEPc, and CA kinetic parameters are provided. These findings describe a new method for the investigation of PEPc kinetics, suggest an HCO3− limitation imposed by CA, and show similarities between the Rubisco temperature responses of previously measured C3 species and the C4 plant S. viridis. PMID:26373659

  16. Promotion of photosynthesis in transgenic rice over-expressing of maize C4 phosphoenolpyruvate carboxylase gene by nitric oxide donors.

    PubMed

    Chen, Pingbo; Li, Xia; Huo, Kai; Wei, Xiaodong; Dai, Chuanchao; Lv, Chuangen

    2014-03-15

    We determined the effects of exogenous nitric oxide on photosynthesis and gene expression in transgenic rice plants (PC) over-expressing the maize C4pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC). Seedlings were subjected to treatments with NO donors, an NO scavenger, phospholipase inhibitors, a Ca(2+) chelator, a Ca(2+) channel inhibitor, and a hydrogen peroxide (H2O2) inhibitor, individually and in various combinations. The NO donors significantly increased the net photosynthetic rate (PN) of PC and wild-type (WT), especially that of PC. Treatment with an NO scavenger did inhibit the PN of rice plants. The treatments with phospholipase inhibitors and a Ca(2+) chelator decreased the PN of WT and PC, and photosynthesis was more strongly inhibited in WT than in PC. Further analyses showed that the NO donors increased endogenous levels of NO and PLD activity, but decreased endogenous levels of Ca(2+) both WT and PC. However, there was a greater increase in NO in WT and a greater increase in PLD activity and Ca(2+) level in PC. The NO donors also increased both PEPC activity and pepc gene expression in PC. PEPC activity can be increased by SNP alone. But the expression of its encoding gene in PC might be regulated by SNP, together with PA and Ca(2+).

  17. Metabolic engineering of cottonseed oil biosynthesis pathway via RNA interference

    PubMed Central

    Xu, Zhongping; Li, Jingwen; Guo, Xiaoping; Jin, Shuangxia; Zhang, Xianlong

    2016-01-01

    Cottonseed oil is recognized as an important oil in food industry for its unique characters: low flavor reversion and the high level of antioxidants (VitaminE) as well as unsaturated fatty acid. However, the cottonseed oil content of cultivated cotton (Gossypium hirsutum) is only around 20%. In this study, we modified the accumulation of oils by the down-regulation of phosphoenolpyruvate carboxylase 1 (GhPEPC1) via RNA interference in transgenic cotton plants. The qRT-PCR and enzyme activity assay revealed that the transcription and expression of GhPEPC1 was dramatically down-regulated in transgenic lines. Consequently, the cottonseed oil content in several transgenic lines showed a significant (P < 0.01) increase (up to 16.7%) without obvious phenotypic changes under filed condition when compared to the control plants. In order to elucidate the molecular mechanism of GhPEPC1 in the regulation of seed oil content, we quantified the expression of the carbon metabolism related genes of transgenic GhPEPC1 RNAi lines by transcriptome analysis. This analysis revealed the decrease of GhPEPC1 expression led to the increase expression of triacylglycerol biosynthesis-related genes, which eventually contributed to the lipid biosynthesis in cotton. This result provides a valuable information for cottonseed oil biosynthesis pathway and shows the potential of creating high cottonseed oil germplasm by RNAi strategy for cotton breeding. PMID:27620452

  18. Low CO2 results in a rearrangement of carbon metabolism to support C4 photosynthetic carbon assimilation in Thalassiosira pseudonana.

    PubMed

    Kustka, Adam B; Milligan, Allen J; Zheng, Haiyan; New, Ashley M; Gates, Colin; Bidle, Kay D; Reinfelder, John R

    2014-11-01

    The mechanisms of carbon concentration in marine diatoms are controversial. At low CO2 , decreases in O2 evolution after inhibition of phosphoenolpyruvate carboxylases (PEPCs), and increases in PEPC transcript abundances, have been interpreted as evidence for a C4 mechanism in Thalassiosira pseudonana, but the ascertainment of which proteins are responsible for the subsequent decarboxylation and PEP regeneration steps has been elusive. We evaluated the responses of T. pseudonana to steady-state differences in CO2 availability, as well as to transient shifts to low CO2 , by integrated measurements of photosynthetic parameters, transcript abundances and quantitative proteomics. On shifts to low CO2 , two PEPC transcript abundances increased and then declined on timescales consistent with recoveries of Fv /Fm , non-photochemical quenching (NPQ) and maximum chlorophyll a-specific carbon fixation (Pmax ), but transcripts for archetypical decarboxylation enzymes phosphoenolpyruvate carboxykinase (PEPCK) and malic enzyme (ME) did not change. Of 3688 protein abundances measured, 39 were up-regulated under low CO2 , including both PEPCs and pyruvate carboxylase (PYC), whereas ME abundance did not change and PEPCK abundance declined. We propose a closed-loop biochemical model, whereby T. pseudonana produces and subsequently decarboxylates a C4 acid via PEPC2 and PYC, respectively, regenerates phosphoenolpyruvate (PEP) from pyruvate in a pyruvate phosphate dikinase-independent (but glycine decarboxylase (GDC)-dependent) manner, and recuperates photorespiratory CO2 as oxaloacetate (OAA).

  19. ppc, the gene for phosphoenolpyruvate carboxylase from an extremely thermophilic bacterium, Rhodothermus obamensis: cloning, sequencing and overexpression in Escherichia coli.

    PubMed

    Takai, K; Sako, Y; Uchida, A

    1998-05-01

    The ppc gene, which encodes phosphoenolpyruvate carboxylase (PEPC) of an extremely thermophilic bacterium, Rhodothermus obamensis, was directly sequenced by the thermal asymmetric interlaced (TAIL) PCR method. An ORF for a 937 amino acid polypeptide was found in the gene. The ppc gene had a high G+C content (66.2 mol%) and the third position of the codon exhibited strong preference for G or C usage (85.0 mol%). The calculated molecular mass was 107,848 Da, which was consistent with the molecular mass of the enzyme as determined by SDS-PAGE (100 kDa). The amino acid sequence of R. obamensis PEPC was closely related to that of PEPC from another thermophile, a Thermus sp., and from a mesophile, Corynebacterium glutamicum, exhibiting 45.3% or 37.7% identity and 61.5% or 56.5% similarity, respectively. By Southern analysis, the ppc gene was found to be present in a single copy in the genomic DNA of this organism. The cloned gene was expressed in Escherichia coli using a pET expression vector system and a thermostable recombinant PEPC was obtained. Comparison of the deduced amino acid sequences of the thermophilic and mesophilic PEPCs revealed distinct or common preferences for specific amino acid composition and substitutions in the two thermophilic enzymes.

  20. CO2 reduction and organic compounds production by photosynthetic bacteria with surface displayed carbonic anhydrase and inducible expression of phosphoenolpyruvate carboxylase.

    PubMed

    Park, Ju-Yong; Kim, Yang-Hoon; Min, Jiho

    2017-01-01

    In Rhodobacter sphaeroides, carbonic anhydrase (CA; EC 4.2.1.1) is a zinc-containing metalloenzyme that catalyzes the reversible hydration of CO2 to HCO3(-) while phosphoenolpyruvate carboxylase (PEPC; 4.1.1.31), an enzyme involved in the carbon metabolism that catalyzed the fixation of CO2 to PEP, is a key factor for biological fixation of CO2 and enhances the production of organic compounds. In this study, the recombinant R. sphaeroides with highly-expressed CA was developed based on a surface displayed system of CA (pJY-OmpCA) on the outer membrane of R. sphaeroides using outer membrane protein (Omp) in R. sphaeroides, Finally, two more different recombinant R. sphaeroides were developed, which transformed with a two-vector system harboring cytosolic expressed CA (pJY-OmpCA-CA)or PEPC (pJY-OMPCA-PEPC) in R. sphaeroides with surface displayed CA on the outer membrane. In case of recombinant R. sphaeroides with the pJY-OmpCA-PEPC, it has shown the highest CO2 reduction efficiency and the production of several organic compounds (carotenoids, polyhydroxybutyrate, malic acid, succinic acid). It means that the surface displayed CA on the R. sphaeroides would accelerate the CO2-bicabonate conversion on the bacterial outer membrane. Moreover, inducible over-expression of PEPC with surface-displayed CA was successfully used to facilitate a rapider CO2 reduction and quicker production of organic compounds.

  1. Metabolic interplay between cytosolic phosphoenolpyruvate carboxylase and mitochondrial alternative oxidase in thermogenic skunk cabbage, Symplocarpus renifolius

    PubMed Central

    Sayed, Md. Abu; Umekawa, Yui; Ito, Kikukatsu

    2016-01-01

    ABSTRACT Skunk cabbage (Symplocarpus renifolius) blooms in early spring and its inflorescence, referred to as the spadix, can produce enough heat to melt snow. Here, we investigated glycolytic carbon flow at the PEP branch-point in thermogenic spadices. Our analyses revealed that petals and pistils in thermogenic florets exhibited higher expression of SrPEPC and SrAOX transcripts than those of SrPK, SrPEPCK, and SrPEPtase. Moreover, enzymatic analyses showed high activities of PEPC in the extracts from thermogenic florets. Finally, mitochondria from thermogenic florets showed low respiratory activities when pyruvate was used as a substrate, although a significant malate-mediated cyanide-insensitive respiration was observed. Collectively, these results suggest that PEP metabolism, primarily catabolized by PEPC, plays a critical role in thermogenesis in S. renifolius. PMID:27739913

  2. Metabolic interplay between cytosolic phosphoenolpyruvate carboxylase and mitochondrial alternative oxidase in thermogenic skunk cabbage, Symplocarpus renifolius.

    PubMed

    Sayed, Md Abu; Umekawa, Yui; Ito, Kikukatsu

    2016-11-01

    Skunk cabbage (Symplocarpus renifolius) blooms in early spring and its inflorescence, referred to as the spadix, can produce enough heat to melt snow. Here, we investigated glycolytic carbon flow at the PEP branch-point in thermogenic spadices. Our analyses revealed that petals and pistils in thermogenic florets exhibited higher expression of SrPEPC and SrAOX transcripts than those of SrPK, SrPEPCK, and SrPEPtase. Moreover, enzymatic analyses showed high activities of PEPC in the extracts from thermogenic florets. Finally, mitochondria from thermogenic florets showed low respiratory activities when pyruvate was used as a substrate, although a significant malate-mediated cyanide-insensitive respiration was observed. Collectively, these results suggest that PEP metabolism, primarily catabolized by PEPC, plays a critical role in thermogenesis in S. renifolius.

  3. Enhanced drought tolerance in transgenic rice over-expressing of maize C4 phosphoenolpyruvate carboxylase gene via NO and Ca(2+).

    PubMed

    Qian, Baoyun; Li, Xia; Liu, Xiaolong; Chen, Pingbo; Ren, Chengang; Dai, Chuanchao

    2015-03-01

    We determined the effects of endogenous nitric oxide and Ca(2+) on photosynthesis and gene expression in transgenic rice plants (PC) over-expressing the maize C4pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC) under drought. In this study, seedlings were subjected to PEG 6000 treatments using PC and wild type (WT; Kitaake). The results showed that, compared with WT, PC had higher relative water content (RWC) and net photosynthetic rate (Pn) under drought. During a 2-day re-watering treatment, Pn recovered faster in PC than in WT. Further analyses showed that, under the drought treatment, the amount of endogenous hydrogen peroxide (H2O2) increased in WT mainly via NADPH oxidase. While in PC, the endogenous nitric oxide (NO) content increased via nitrate reductase and nitric oxide synthase on day 2 of the drought treatment and day 1 of the re-watering treatment. After 2 days of drought treatment, PC also showed higher PEPC activity, calcium content, phospholipase D (PLD) activity, C4-pepc and NAC6 transcript levels, and protein kinase activity as compared with PC without treatment. These changes did not occur in WT. Correlation analysis also proved NO associated with these indicators in PC. Based on these results, there was a particular molecular mechanism of drought tolerance in PC. The mechanism is related to the signaling processes via NO and Ca(2+) involving the protein kinase and the transcription factor, resulted in up-regulation of PEPC activity and its gene expression, such as C4pepc. Some genes encode antioxidant system, cu/zn-sod as well, which promote antioxidant system to clear MDA and superoxide anion radical, thereby conferring drought tolerance.

  4. Improved oxidative tolerance in suspension-cultured cells of C4-pepctransgenic rice by H2O2 and Ca(2+) under PEG-6000.

    PubMed

    Qian, Baoyun; Li, Xia; Liu, Xiaolong; Wang, Man

    2015-06-01

    To understand the molecular responses of PC (Overexpressing the maize C4-pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC)), to drought stress at cell level, we analyzed changes in the levels of signaling molecules (hydrogen peroxide (H2O2), calcium ion (Ca(2+)), and nitric oxide (NO)) in suspension-cultured PC and wild-type (WT) rice (Oryza sativa L.) cell under drought stress induced by 20% polyethylene glycol 6000 (PEG-6000). Results demonstrated that PC improved drought tolerance by enhancing antioxidant defense, retaining higher relative water content, survival percentages, and dry weight of cells. In addition, PEPC activity in PC under PEG treatment was strengthened by addition of H2O2 inhibitor, dimethylthiourea (DMTU) and NO synthesis inhibitor, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), respectively, while that in PC was weakened by addition of free calcium chelator, ethylene glycol-bis(b-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) + calcium channel outflow inhibitor, ruthenium red (RR) + plasma membrane channel blocker La(NO3)3, but EGTA + RR did not. Results also showed that NO and Ca(2+) was lying downstream of H2O2 in drought-induced signaling. Calcium ion was also involved in the expression of C4-pepc in PC. These results suggested that PC could improve oxidative tolerance in suspension-cultured cells and the acquisition of this tolerance required downregulation of H2O2 and the entry of extracellular Ca(2+) into cells across the plasma membrane for regulation of PEPC activity and C4-pepc expression.

  5. Towards efficient photosynthesis: overexpression of Zea mays phosphoenolpyruvate carboxylase in Arabidopsis thaliana.

    PubMed

    Kandoi, Deepika; Mohanty, Sasmita; Govindjee; Tripathy, Baishnab C

    2016-12-01

    Plants with C4 photosynthesis are efficient in carbon assimilation and have an advantage over C3 photosynthesis. In C4 photosynthesis, the primary CO2 fixation is catalyzed by phosphoenolpyruvate carboxylase (PEPC). Here, we show that overexpression of Zea mays PEPC cDNA, under the control of (35)S promoter, in Arabidopsis thaliana resulted in ~7-10 fold higher protein abundance and ~7-10 fold increase in PEPC activity in the transgenic lines than that in the vector control. We suggest that overexpression of PEPC played an anaplerotic role to increase the supply of 4-carbon carboxylic acids, which provided carbon skeletons for increased amino acid and protein synthesis. Higher protein content must have been responsible for increased metabolic processes including chlorophyll biosynthesis, photosynthesis, and respiration. Consequently, the PEPC-overexpressed transgenic plants had higher chlorophyll content, enhanced electron transport rate (ETR), lower non-photochemical quenching (NPQ) of chlorophyll a fluorescence, and a higher performance index (PI) than the vector control. Consistent with these observations, the rate of CO2 assimilation, the starch content, and the dry weight of PEPC-overexpressed plants increased by 14-18 %, 10-18 %, and 6.5-16 %, respectively. Significantly, transgenics were tolerant to salt stress as they had increased ability to synthesize amino acids, including the osmolyte proline. NaCl (150 mM)-treated transgenic plants had higher variable to maximum Chl a fluorescence (F v/F m) ratio, higher PI, higher ETR, and lower NPQ than the salt-treated vector controls. These results suggest that expression of C4 photosynthesis enzyme(s) in a C3 plant can improve its photosynthetic capacity with enhanced tolerance to salinity stress.

  6. Identification and expression of a soybean nodule-enhanced PEP-carboxylase kinase gene (NE-PpcK) that shows striking up-/down-regulation in vivo.

    PubMed

    Xu, Wenxin; Zhou, You; Chollet, Raymond

    2003-05-01

    Various isoforms of plant phosphoenolpyruvate carboxylase (PEPC (Ppc)) are controlled post-translationally by an intricate interaction between allosteric regulation and reversible protein phosphorylation. In leaves and root nodules of legumes, these changes in PEPC phosphorylation state are governed primarily by PEPC-kinase (PpcK), a novel, 'minimal but functional' Ser/Thr kinase. To date, this plant-specific kinase has been investigated in molecular terms exclusively in non-leguminous plants, such as Crassulacean-acid-metabolism (CAM) species and Arabidopsis. As an important extension of our earlier biochemical studies on this dedicated kinase and PEPC phosphorylation in soybean (Glycine max) nodules, we now report the molecular cloning of the first legume PpcK from a soybean nodule cDNA library, which encodes a functional, 31.0 kDa PpcK polypeptide. Besides displaying organ, developmental, and spatial expression properties that are strikingly up-regulated in mature nodules, the expression pattern of this transcript is distinct from that of a second soybean PpcK isogene (GmPpcK). The steady-state abundance of this former, nodule-enhanced transcript (NE-PpcK) is markedly influenced by photosynthate supply from the shoots. This latter up-/down-regulation of NE-PpcK transcript level occurs in vivo in concert with the corresponding changes in the nodule PpcK activity, the phosphorylation-state of PEPC, and the abundance of a previously identified, nodule-enhanced transcript (GmPEPC7) that encodes the target enzyme (NE-Ppc). Furthermore, genomic Southern analysis and inspection of the public database indicate that there are at least three distinct PpcK and Ppc isogenes in soybean. Collectively, these and recent findings with Arabidopsis implicate the existence of multiple PpcK-Ppc'expression-partners' in plants, exemplified by NE-PpcK and NE-Ppc in the soybean nodule.

  7. Phosphoenolpyruvate carboxylase protein kinase from developing castor oil seeds: partial purification, characterization, and reversible control by photosynthate supply.

    PubMed

    Murmu, Jhadeswar; Plaxton, William C

    2007-10-01

    Phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) protein kinase (PPCK) was purified approximately 1,500-fold from developing castor oil seeds (COS). Gel filtration and immunoblotting with anti-(rice PPCK2)-immune serum indicated that this Ca2+-insensitive PPCK exists as a 31-kDa monomer. COS PPCK-mediated rephosphorylation of the 107-kDa subunit (p107) of COS PEPC1 (Km = 2.2 microM) activated PEPC1 by approximately 80% when assayed under suboptimal conditions (pH 7.3, 0.2 mM PEP, and 0.125 mM malate). COS PPCK displayed remarkable selectivity for phosphorylating COS PEPC1 (relative to tobacco, sorghum, or maize PEPCs), exhibited a broad pH-activity optima of approximately pH 8.5, and at pH 7.3 was activated 40-65% by 1 mM PEP, or 10 mM Gln or Asn, but inhibited 65% by 10 mM L-malate. The possible control of COS PPCK by disulfide-dithiol interconversion was suggested by its rapid inactivation and subsequent reactivation when incubated with oxidized glutathione and then dithiothreitol. In vitro PPCK activity correlated with in vivo p107 phosphorylation status, with both peaking in mid-cotyledon to full-cotyledon developing COS. Notably, PPCK activity and p107 phosphorylation of developing COS were eliminated following pod excision or prolonged darkness of intact plants. Both effects were fully reversed 12 h following reillumination of darkened plants. These results implicate a direct relationship between the up-regulation of COS PPCK and p107 phosphorylation during the recommencement of photosynthate delivery from illuminated leaves to the non-photosynthetic COS. Overall, the results support the hypothesis that PEPC and PPCK participate in the control of photosynthate partitioning into C-skeletons needed as precursors for key biosynthetic pathways of developing COS.

  8. Deployment, commissioning, and operation of plasma electrode Pockels cells in the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Arnold, Phillip A.; Ollis, Craig W.; Hinz, Andrew F.; Robb, Calvin L.; Primdahl, Keith A.; Watson, Jayson J.; O'Brien, Michael D.; Funkhouser, William G.; Biltoft, Peter J.; Shelton, Randy T.; Tapley, William C.; DeHope, William J.

    2004-05-01

    Large aperture Plasma Electrode Pockels Cells (PEPCs) are an enabling technology in the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. The Pockels cells allow the NIF laser to take advantage of multipass main amplifier architecture, thus reducing costs and physical size of the facility. Each Pockels cell comprises four 40-cm x 40-cm apertures arranged in a 4x1 array. The combination of the Pockels cell and a thin-film polarizer, also configured in a 4x1 array, forms an optical switch that is key to achieving the required multi-pass operation. The operation of the PEPC is a follows: Before the arrival of the laser pulse, optically transparent, low-density helium plasmas are initiated to serve as electrodes for the KDP crystals mounted in the Pockels cell. During beam propagation through the main laser cavity a longitudinal electric field is impressed on the electro-optic crystals. The polarization of the propagating beams is rotated by 90° on each of two passes, thereby allowing the beam to be trapped in the main laser amplifier cavity for a total of four passes before being switched out into the cavity spatial filter. The physics aspects of the PEPC are well documented. Consequently, this paper will emphasize the PEPC subsystem in the context of its role and relevance within the broader NIF laser system, provide a view of the complexity of the subsystem and give an overview of PEPC's interactions with other elements of NIF, including interfaces to the Beamline Infrastructure, the NIF Timing Subsystem, and the Integrated Computer Control System (ICCS); along with dependence on the Optics Production, Transport and Handling (T&H), and Assembly, Integration and Refurbishment (AIR) and Operations organizations. Further, we will discuss implementation details related to the functional blocks and individual components that comprise PEPC, with particular emphasis on the unique constraints placed on the elements and the attendant

  9. Multiple isoforms of phosphoenolpyruvate carboxylase in the Orchidaceae (subtribe Oncidiinae): implications for the evolution of crassulacean acid metabolism.

    PubMed

    Silvera, Katia; Winter, Klaus; Rodriguez, B Leticia; Albion, Rebecca L; Cushman, John C

    2014-07-01

    Phosphoenolpyruvate carboxylase (PEPC) catalyses the initial fixation of atmospheric CO2 into oxaloacetate and subsequently malate. Nocturnal accumulation of malic acid within the vacuole of photosynthetic cells is a typical feature of plants that perform crassulacean acid metabolism (CAM). PEPC is a ubiquitous plant enzyme encoded by a small gene family, and each member encodes an isoform with specialized function. CAM-specific PEPC isoforms probably evolved from ancestral non-photosynthetic isoforms by gene duplication events and subsequent acquisition of transcriptional control elements that mediate increased leaf-specific or photosynthetic-tissue-specific mRNA expression. To understand the patterns of functional diversification related to the expression of CAM, ppc gene families and photosynthetic patterns were characterized in 11 closely related orchid species from the subtribe Oncidiinae with a range of photosynthetic pathways from C3 photosynthesis (Oncidium cheirophorum, Oncidium maduroi, Rossioglossum krameri, and Oncidium sotoanum) to weak CAM (Oncidium panamense, Oncidium sphacelatum, Gomesa flexuosa and Rossioglossum insleayi) and strong CAM (Rossioglossum ampliatum, Trichocentrum nanum, and Trichocentrum carthagenense). Phylogenetic analysis revealed the existence of two main ppc lineages in flowering plants, two main ppc lineages within the eudicots, and three ppc lineages within the Orchidaceae. Our results indicate that ppc gene family expansion within the Orchidaceae is likely to be the result of gene duplication events followed by adaptive sequence divergence. CAM-associated PEPC isoforms in the Orchidaceae probably evolved from several independent origins.

  10. 76 FR 28453 - Cesar Chavez Special Resource Study-Alameda, Fresno, Imperial, Kern, Los Angeles, Monterey...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-17

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  11. Chalcone-based Selective Inhibitors of a C4 Plant Key Enzyme as Novel Potential Herbicides

    NASA Astrophysics Data System (ADS)

    Nguyen, G. T. T.; Erlenkamp, G.; Jäck, O.; Küberl, A.; Bott, M.; Fiorani, F.; Gohlke, H.; Groth, G.

    2016-06-01

    Weeds are a challenge for global food production due to their rapidly evolving resistance against herbicides. We have identified chalcones as selective inhibitors of phosphoenolpyruvate carboxylase (PEPC), a key enzyme for carbon fixation and biomass increase in the C4 photosynthetic pathway of many of the world’s most damaging weeds. In contrast, many of the most important crop plants use C3 photosynthesis. Here, we show that 2‧,3‧,4‧,3,4-Pentahydroxychalcone (IC50 = 600 nM) and 2‧,3‧,4‧-Trihydroxychalcone (IC50 = 4.2 μM) are potent inhibitors of C4 PEPC but do not affect C3 PEPC at a same concentration range (selectivity factor: 15–45). Binding and modeling studies indicate that the active compounds bind at the same site as malate/aspartate, the natural feedback inhibitors of the C4 pathway. At the whole plant level, both substances showed pronounced growth-inhibitory effects on the C4 weed Amaranthus retroflexus, while there were no measurable effects on oilseed rape, a C3 plant. Growth of selected soil bacteria was not affected by these substances. Our chalcone compounds are the most potent and selective C4 PEPC inhibitors known to date. They offer a novel approach to combat C4 weeds based on a hitherto unexplored mode of allosteric inhibition of a C4 plant key enzyme.

  12. Constitutive and dark-induced expression of Solanum tuberosum phosphoenolpyruvate carboxylase enhances stomatal opening and photosynthetic performance of Arabidopsis thaliana.

    PubMed

    Kebeish, Rashad; Niessen, Markus; Oksaksin, Mehtap; Blume, Christian; Peterhaensel, Christoph

    2012-02-01

    The effect of constitutive and dark-induced expression of Solanum tuberosum phosphoenolpyruvate carboxylase (PEPC) on the opening state of stomata and photosynthetic performance in Arabidopsis thaliana plants was studied. Transcript accumulation analyses of the A. thaliana dark-induced (Din10 and Din6) and the Pisum sativum asparagine synthetase 2 promoters (Asn2) in transiently transformed tobacco leaves showed that Din10 promoter induced more DsRed accumulation in the dark compared to the other din genes. Overexpression of PEPC under the control of the constitutive enhanced CaMV 35S (p35SS) and dark-induced Din10 promoter in stably transformed A. thaliana plants increased the number of opened stomata in dark adapted leaves. Gas exchange measurements using A. thaliana plants transgenic for p35SS-PEPC and Din10-PEPC revealed a marked increase in stomatal conductance, transpiration, and dark respiration rates measured in the dark compared to wild-type plants. Moreover, measurement of CO(2) assimilation rates at different external CO(2) concentrations (C(a) ) and different light intensities shows an increase in the CO(2) assimilation rates in transgenic Arabidopsis lines compared to wild-type plants. This is considered as first step towards transferring the aspects of Crassulacean acid metabolism-like photosynthetic mechanism into C3 plants.

  13. Chalcone-based Selective Inhibitors of a C4 Plant Key Enzyme as Novel Potential Herbicides

    PubMed Central

    Nguyen, G. T. T.; Erlenkamp, G.; Jäck, O.; Küberl, A.; Bott, M.; Fiorani, F.; Gohlke, H.; Groth, G.

    2016-01-01

    Weeds are a challenge for global food production due to their rapidly evolving resistance against herbicides. We have identified chalcones as selective inhibitors of phosphoenolpyruvate carboxylase (PEPC), a key enzyme for carbon fixation and biomass increase in the C4 photosynthetic pathway of many of the world’s most damaging weeds. In contrast, many of the most important crop plants use C3 photosynthesis. Here, we show that 2′,3′,4′,3,4-Pentahydroxychalcone (IC50 = 600 nM) and 2′,3′,4′-Trihydroxychalcone (IC50 = 4.2 μM) are potent inhibitors of C4 PEPC but do not affect C3 PEPC at a same concentration range (selectivity factor: 15–45). Binding and modeling studies indicate that the active compounds bind at the same site as malate/aspartate, the natural feedback inhibitors of the C4 pathway. At the whole plant level, both substances showed pronounced growth-inhibitory effects on the C4 weed Amaranthus retroflexus, while there were no measurable effects on oilseed rape, a C3 plant. Growth of selected soil bacteria was not affected by these substances. Our chalcone compounds are the most potent and selective C4 PEPC inhibitors known to date. They offer a novel approach to combat C4 weeds based on a hitherto unexplored mode of allosteric inhibition of a C4 plant key enzyme. PMID:27263468

  14. Overproduction of C4 photosynthetic enzymes in transgenic rice plants: an approach to introduce the C4-like photosynthetic pathway into rice.

    PubMed

    Taniguchi, Yojiro; Ohkawa, Hiroshi; Masumoto, Chisato; Fukuda, Takuya; Tamai, Tesshu; Lee, Kwanghong; Sudoh, Sizue; Tsuchida, Hiroko; Sasaki, Haruto; Fukayama, Hiroshi; Miyao, Mitsue

    2008-01-01

    Four enzymes, namely, the maize C(4)-specific phosphoenolpyruvate carboxylase (PEPC), the maize C(4)-specific pyruvate, orthophosphate dikinase (PPDK), the sorghum NADP-malate dehydrogenase (MDH), and the rice C(3)-specific NADP-malic enzyme (ME), were overproduced in the mesophyll cells of rice plants independently or in combination. Overproduction individually of PPDK, MDH or ME did not affect the rate of photosynthetic CO(2) assimilation, while in the case of PEPC it was slightly reduced. The reduction in CO(2) assimilation in PEPC overproduction lines remained unaffected by overproduction of PPDK, ME or a combination of both, however it was significantly restored by the combined overproduction of PPDK, ME, and MDH to reach levels comparable to or slightly higher than that of non-transgenic rice. The extent of the restoration of CO(2) assimilation, however, was more marked at higher CO(2) concentrations, an indication that overproduction of the four enzymes in combination did not act to concentrate CO(2) inside the chloroplast. Transgenic rice plants overproducing the four enzymes showed slight stunting. Comparison of transformants overproducing different combinations of enzymes indicated that overproduction of PEPC together with ME was responsible for stunting, and that overproduction of MDH had some mitigating effects. Possible mechanisms underlying these phenotypic effects, as well as possibilities and limitations of introducing the C(4)-like photosynthetic pathway into C(3) plants, are discussed.

  15. CO(2)-fixing enzymes during moulting from third larval to fourth larval stage of Anisakis simplex and Hysterothylacium aduncum (Nematoda: Anisakidae).

    PubMed

    Iglesias, Luis; Malagón, David; Valero, Adela; Benítez, Rocío; Adroher, F J; Javier Adroher, F

    2005-06-01

    The fixing of CO(2) is an important metabolic process for many organisms. In the anisakid nematodes, CO(2) has been shown to be necessary for their development, at least in vitro. The presence of CO(2) stimulates the moulting (M3) of the larvae from the third (L3) to the fourth (L4) stage and prolongs the survival, at least, in vitro. We determined the activity of CO(2)-fixing enzymes, common to many organisms, in two anisakids: Anisakis simplex, a parasite of cetaceans, and Hysterothylacium aduncum, a parasite of fish. Although no activity was detected for pyruvate carboxylase or carboxylating-malic enzyme, we detected phosphoenolpyruvate carboxykinase (PEPCK) and phosphoenolpyruvate carboxylase (PEPC) activity. In A. simplex, PEPCK was clearly higher than that of PEPC throughout the moulting process studied. In H. aduncum, although the activity of both enzymes was of similar magnitude, they showed different behaviour; PEPCK activity decreased after the moulting to L4, PEPC activity increased so that the ratio PEPCK/PEPC activity decreased from 1.90 before moulting to 0.59 after.

  16. Multiple isoforms of phosphoenolpyruvate carboxylase in the Orchidaceae (subtribe Oncidiinae): implications for the evolution of crassulacean acid metabolism

    PubMed Central

    Silvera, Katia; Winter, Klaus; Rodriguez, B. Leticia; Albion, Rebecca L.; Cushman, John C.

    2014-01-01

    Phosphoenolpyruvate carboxylase (PEPC) catalyses the initial fixation of atmospheric CO2 into oxaloacetate and subsequently malate. Nocturnal accumulation of malic acid within the vacuole of photosynthetic cells is a typical feature of plants that perform crassulacean acid metabolism (CAM). PEPC is a ubiquitous plant enzyme encoded by a small gene family, and each member encodes an isoform with specialized function. CAM-specific PEPC isoforms probably evolved from ancestral non-photosynthetic isoforms by gene duplication events and subsequent acquisition of transcriptional control elements that mediate increased leaf-specific or photosynthetic-tissue-specific mRNA expression. To understand the patterns of functional diversification related to the expression of CAM, ppc gene families and photosynthetic patterns were characterized in 11 closely related orchid species from the subtribe Oncidiinae with a range of photosynthetic pathways from C3 photosynthesis (Oncidium cheirophorum, Oncidium maduroi, Rossioglossum krameri, and Oncidium sotoanum) to weak CAM (Oncidium panamense, Oncidium sphacelatum, Gomesa flexuosa and Rossioglossum insleayi) and strong CAM (Rossioglossum ampliatum, Trichocentrum nanum, and Trichocentrum carthagenense). Phylogenetic analysis revealed the existence of two main ppc lineages in flowering plants, two main ppc lineages within the eudicots, and three ppc lineages within the Orchidaceae. Our results indicate that ppc gene family expansion within the Orchidaceae is likely to be the result of gene duplication events followed by adaptive sequence divergence. CAM-associated PEPC isoforms in the Orchidaceae probably evolved from several independent origins. PMID:24913627

  17. The Importance of the Strictly Conserved, C-terminal Glycine Residue in Phosphoenolpyruvate Carboxylase for Overall Catalysis: Mutagenesis and Truncation of GLY-961 in the Sorghum C4 Leaf Isoform

    SciTech Connect

    Xu,W.; Ahmed, S.; Moriyama, H.; Chollet, R.

    2006-01-01

    Phosphoenolpyruvate carboxylase (PEPC) is a 'multifaceted', allosteric enzyme involved in C4 acid metabolism in green plants/microalgae and prokaryotes. Before the elucidation of the three-dimensional structures of maize C4 leaf and Escherichia coli PEPC, our truncation analysis of the sorghum C4 homologue revealed important roles for the enzyme's C-terminal {alpha}-helix and its appended QNTG{sup 961} tetrapeptide in polypeptide stability and overall catalysis, respectively. Collectively, these functional and structural observations implicate the importance of the PEPC C-terminal tetrapeptide for both catalysis and negative allosteric regulation. We have now more finely dissected this element of PEPC structure-function by modification of the absolutely conserved C-terminal glycine of the sorghum C4 isoform by site-specific mutagenesis (G961(A/V/D)) and truncation ({Delta}C1/C4). Although the C4 polypeptide failed to accumulate in a PEPC{sup -} strain (XH11) of E. coli transformed with the Asp mutant, the other variants were produced at wild-type levels. Although neither of these four mutants displayed an apparent destabilization of the purified PEPC homotetramer, all were compromised catalytically in vivo and in vitro. Functional complementation of XH11 cells under selective growth conditions was restricted progressively by the Ala, {Delta}C1 and Val, and {Delta}C4 modifications. Likewise, steady-state kinetic analysis of the purified mutant enzymes revealed corresponding negative trends in k{sub cat} and k{sub cat}/K0.5 (phosphoenolpyruvate) but not in K{sub 0.5} or the Hill coefficient. Homology modeling of these sorghum C-terminal variants against the structure of the closely related maize C4 isoform predicted perturbations in active-site molecular cavities and/or ion-pairing with essential, invariant Arg-638. These collective observations reveal that even a modest, neutral alteration of the PEPC C-terminal hydrogen atom side chain is detrimental to enzyme

  18. Photosynthetic carbon assimilation in the coccolithophorid Emiliania huxleyi (Haptophyta): Evidence for the predominant operation of the c3 cycle and the contribution of {beta}-carboxylases to the active anaplerotic reaction.

    PubMed

    Tsuji, Yoshinori; Suzuki, Iwane; Shiraiwa, Yoshihiro

    2009-02-01

    The coccolithophorid Emiliania huxleyi (Haptophyta) is a representative and unique marine phytoplankton species that fixes inorganic carbon by photosynthesis and calci-fication. We examined the initial process of photosynthetic carbon assimilation by analyses of metabolites, enzymes and genes. When the cells were incubated with a radioactive substrate (2.3 mM NaH(14)CO(3)) for 10 s under illumination, 70% of the (14)C was incorporated into the 80% methanol-soluble fraction. Eighty-five and 15% of (14)C in the soluble fraction was incorporated into phosphate esters (P-esters), including the C(3) cycle intermediates and a C(4) compound, aspartate, respectively. A pulse-chase experiment showed that (14)C in P-esters was mainly transferred into lipids, while [(14)C]aspartate, [(14)C]alanine and [(14)C]glutamate levels remained almost constant. These results indicate that the C(3) cycle functions as the initial pathway of carbon assimilation and that beta-carboxylation contributes to the production of amino acids in subsequent metabolism. Transcriptional analysis of beta-carboxylases such as pyruvate carboxylase (PYC), phosphoenolpyruvate carboxylase (PEPC) and phosphoenolpyruvate carboxykinase (PEPCK) revealed that PYC and PEPC transcripts were greatly increased under illumination, whereas the PEPCK transcript decreased remarkably. PEPC activity was higher in light-grown cells than in dark-adapted cells. PYC activity was detected in isolated chloroplasts of light-grown cells. According to analysis of their deduced N-terminal sequence, PYC and PEPC are predicted to be located in the chloroplasts and mitochondria, respectively. These results suggest that E. huxleyi possesses unique carbon assimila-tion mechanisms in which beta-carboxylation by both PYC and PEPC plays important roles in different organelles.

  19. Regulation and Localization of Key Enzymes during the Induction of Kranz-Less, C4-Type Photosynthesis in Hydrilla verticillata.

    PubMed Central

    Magnin, N. C.; Cooley, B. A.; Reiskind, J. B.; Bowes, G.

    1997-01-01

    Kranz-less, C4-type photosynthesis was induced in the submersed monocot Hydrilla verticillata (L.f.) Royle. During a 12-d induction period the CO2 compensation point and O2 inhibition of photosynthesis declined linearly. Phosphoenolpyruvate carboxylase (PEPC) activity increased 16-fold, with the major increase occurring within 3 d. Asparagine and alanine aminotransferases were also induced rapidly. Pyruvate orthophosphate dikinase (PPDK) and NADP-malic enzyme (ME) activities increased 10-fold but slowly over 15 d. Total ribulose-1,5-bisphosphate carboxylase/oxygenase activity did not increase, and its activation declined from 82 to 50%. Western blots for PEPC, PPDK, and NADP-ME indicated that increased protein levels were involved in their induction. The H. verticillata NADP-ME polypeptide was larger (90 kD) than the maize C4 enzyme (62 kD). PEPC and PPDK exhibited up-regulation in the light. Subcellular fractionation of C4-type leaves showed that PEPC was cytosolic, whereas PPDK and NADP-ME were located in the chloroplasts. The O2 inhibition of photosynthesis was doubled when C4-type but not C3-type leaves were exposed to diethyl oxalacetate, a PEPC inhibitor. The data are consistent with a C4-cycle concentrating CO2 in H. verticillata chloroplasts and indicate that Kranz anatomy is not obligatory for C4-type photosynthesis. H. verticillata predates modern terrestrial C4 monocots; therefore, this inducible CO2-concentrating mechanism may represent an ancient form of C4 photosynthesis. PMID:12223888

  20. A graphical approach to tracking and reporting target status in structural genomics.

    PubMed

    Pan, Xiaokang; Wesenberg, Gary E; Markley, John L; Fox, Brian G; Phillips, George N; Bingman, Craig A

    2007-12-01

    Determination of a protein structure requires a series of decisions and processes, starting with target selection, through cloning, expression, purification, and finally structure determination. Structural genomics projects may distribute these steps among several different groups of researchers. Although this division may achieve a lower cost per solved structure, it creates a unique set of challenges for integrating and passing information on the progress of a given target across several functional divisions. Laboratory information management systems (LIMS) are essential for gathering this information, but may not display the progress of a given target in an intuitive way. In addition, structural genomics projects funded by the Protein Structure Initiative (PSI) are obliged to disseminate data regularly to the TargetDB and PepcDB data repositories, and this requires the creation of specialized views of the data. We report here how the flow of a target through a structural genomics pipeline and reports to TargetDB and PepcDB can be abstracted as directed acyclic graphs or trees. To implement this kind of display, we created software that tracks the flow of activity leading toward protein structure determination and prepares XML reports as input to TargetDB and PepcDB. The target tracing software consists of a set of Perl CGI scripts that integrate with the Graphviz visualization system to provide a graphical, user-friendly Web interface. The database reporting software, also coded in Perl, transfers large-scale genomics data from our LIMS into a PepcDB reportable XML file. This software package has facilitated inter-group communication, improved the quality and accuracy of information in our LIMS, and increased the efficiency and accuracy of our reports to PepcDB.

  1. Evolution of the Phosphoenolpyruvate Carboxylase Protein Kinase Family in C3 and C4 Flaveria spp.1[W][OPEN

    PubMed Central

    Aldous, Sophia H.; Weise, Sean E.; Sharkey, Thomas D.; Waldera-Lupa, Daniel M.; Stühler, Kai; Mallmann, Julia; Groth, Georg; Gowik, Udo; Westhoff, Peter; Arsova, Borjana

    2014-01-01

    The key enzyme for C4 photosynthesis, Phosphoenolpyruvate Carboxylase (PEPC), evolved from nonphotosynthetic PEPC found in C3 ancestors. In all plants, PEPC is phosphorylated by Phosphoenolpyruvate Carboxylase Protein Kinase (PPCK). However, differences in the phosphorylation pattern exist among plants with these photosynthetic types, and it is still not clear if they are due to interspecies differences or depend on photosynthetic type. The genus Flaveria contains closely related C3, C3-C4 intermediate, and C4 species, which are evolutionarily young and thus well suited for comparative analysis. To characterize the evolutionary differences in PPCK between plants with C3 and C4 photosynthesis, transcriptome libraries from nine Flaveria spp. were used, and a two-member PPCK family (PPCKA and PPCKB) was identified. Sequence analysis identified a number of C3- and C4-specific residues with various occurrences in the intermediates. Quantitative analysis of transcriptome data revealed that PPCKA and PPCKB exhibit inverse diel expression patterns and that C3 and C4 Flaveria spp. differ in the expression levels of these genes. PPCKA has maximal expression levels during the day, whereas PPCKB has maximal expression during the night. Phosphorylation patterns of PEPC varied among C3 and C4 Flaveria spp. too, with PEPC from the C4 species being predominantly phosphorylated throughout the day, while in the C3 species the phosphorylation level was maintained during the entire 24 h. Since C4 Flaveria spp. evolved from C3 ancestors, this work links the evolutionary changes in sequence, PPCK expression, and phosphorylation pattern to an evolutionary phase shift of kinase activity from a C3 to a C4 mode. PMID:24850859

  2. Identification of peptide sequences that target to the brain using in vivo phage display.

    PubMed

    Li, Jingwei; Zhang, Qizhi; Pang, Zhiqing; Wang, Yuchen; Liu, Qingfeng; Guo, Liangran; Jiang, Xinguo

    2012-06-01

    Phage display technology could provide a rapid means for the discovery of novel peptides. To find peptide ligands specific for the brain vascular receptors, we performed a modified phage display method. Phages were recovered from mice brain parenchyma after administrated with a random 7-mer peptide library intravenously. A longer circulation time was arranged according to the biodistributive brain/blood ratios of phage particles. Following sequential rounds of isolation, a number of phages were sequenced and a peptide sequence (CTSTSAPYC, denoted as PepC7) was identified. Clone 7-1, which encodes PepC7, exhibited translocation efficiency about 41-fold higher than the random library phage. Immunofluorescence analysis revealed that Clone 7-1 had a significant superiority on transport efficiency into the brain compared with native M13 phage. Clone 7-1 was inhibited from homing to the brain in a dose-dependent fashion when cyclic peptides of the same sequence were present in a competition assay. Interestingly, the linear peptide (ATSTSAPYA, Pep7) and a scrambled control peptide PepSC7 (CSPATSYTC) did not compete with the phage at the same tested concentration (0.2-200 pg). Labeled by Cy5.5, PepC7 exhibited significant brain-targeting capability in in vivo optical imaging analysis. The cyclic conformation of PepC7 formed by disulfide bond, and the correct structure itself play a critical role in maintaining the selectivity and affinity for the brain. In conclusion, PepC7 is a promising brain-target motif never been reported before and it could be applied to targeted drug delivery into the brain.

  3. Was low CO2 a driving force of C4 evolution: Arabidopsis responses to long-term low CO2 stress.

    PubMed

    Li, Yuanyuan; Xu, Jiajia; Haq, Noor Ul; Zhang, Hui; Zhu, Xin-Guang

    2014-07-01

    The responses of long-term growth of plants under elevated CO2 have been studied extensively. Comparatively, the responses of plants to subambient CO2 concentrations have not been well studied. This study aims to investigate the responses of the model C3 plant, Arabidopsis thaliana, to low CO2 at the molecular level. Results showed that low CO2 dramatically decreased biomass productivity, together with delayed flowering and increased stomatal density. Furthermore, alteration of thylakoid stacking in both bundle sheath and mesophyll cells, upregulation of PEPC and PEPC-K together with altered expression of a number of regulators known involved in photosynthesis development were observed. These responses to low CO2 are discussed with regard to the fitness of C3 plants under low CO2. This work also briefly discusses the relevance of the data to C4 photosynthesis evolution.

  4. Optical transmission in thin films of vanadium compounds

    NASA Astrophysics Data System (ADS)

    Karimov, Kh. S.; Mahroof-Tahir, M.; Saleem, M.; Ahmad, N.; Rashid, A.

    2014-07-01

    Thin films of five vanadium compounds/composite: (1) VO2(3-fl) (3-fl = 3-Hydroxyflavone), (2) VO(pbd)2 (pbd = 1-Phenyl-1, 3-butadione), (3) VO(dbm)2 (dbm = Dibenzoylmethane), (4) VPc (Vanadyl Phthalocyanine) and (5) V2O5-PEPC (V2O5- poly-N-epoxypropylcarbazole composite), were deposited by the drop-casting method from the solution in benzene. The transmittance—irradiance relationships were investigated and the transmission in the visible spectrum and optical images were obtained as well. It was found that the transmittance of the VO2(3-fl), VO(pbd)2, VO(dbm)2 and VPc, was practically independent of the irradiance; whereas the transmittance of V2O5-PEPC decreased by 4% for thin and 9% for thick films with an increase of the irradiance.

  5. Effects of granulation on organic acid metabolism and its relation to mineral elements in Citrus grandis juice sacs.

    PubMed

    Wang, Xian-You; Wang, Ping; Qi, Yi-Ping; Zhou, Chen-Ping; Yang, Lin-Tong; Liao, Xin-Yan; Wang, Liu-Qing; Zhu, Dong-Huang; Chen, Li-Song

    2014-02-15

    We investigated the effects of granulation on organic acid metabolism and its relation to mineral elements in 'Guanximiyou' pummelo (Citrus grandis) juice sacs. Granulated juice sacs had decreased concentrations of citrate and isocitrate, thus lowering juice sac acidity. By contrast, malate concentration was higher in granulated juice sacs than in normal ones. The reduction in citrate concentration might be caused by increased degradation, as indicated by enhanced aconitase activity, whilst the increase in malate concentration might be caused by increased biosynthesis, as indicated by enhanced phosphoenolpyruvate carboxylase (PEPC). Real time quantitative reverse transcription PCR (qRT-PCR) analysis showed that the activities of most acid-metabolizing enzymes were regulated at the transcriptional level, whilst post-translational modifications might influence the PEPC activity. Granulation led to increased accumulation of mineral elements (especially phosphorus, magnesium, sulphur, zinc and copper) in juice sacs, which might be involved in the incidence of granulation in pummelo fruits.

  6. Regulation of enzymes involved in C(4) photosynthesis and the antioxidant metabolism by UV-B radiation in Egeria densa, a submersed aquatic species.

    PubMed

    Casati, Paula; Lara, María V; Andreo, Carlos S

    2002-01-01

    Egeria densa, a submersed aquatic species, was exposed to different treatments under UV-B radiation, and the response of phosphoenolpyruvate carboxylase (PEPC) and NADP-malic enzyme (NADP-ME) was determined. Exposure to UV-B radiation for 4 h per day over 7-16 days caused an increase in both enzymes, together with an increase in the activity of some isoforms of several enzymes involved in the antioxidant metabolism, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD). The content of chlorophylls and carotenoids was considerably decreased, suggesting that degradation or repression of the synthesis of these molecules may be occurring after UV-B exposure. Reactive oxygen species (ROS) were also required for UV-B induction of PEPC and NADP-ME, as the addition of ascorbic acid before UV-B treatment prevented the induction of these enzymes, while salicylic acid was not effective in inducing NADP-ME but increased the expression of the lower molecular mass isoform of PEPC. On the other hand, damage to the photosynthetic machinery may be occurring after exposure to UV-B radiation for 8 per day over 1-2 days, as indicated by a decrease in the levels of Rubisco, PEPC and NADP-ME. Some of the enzymes involved in the antioxidant metabolism, such as CAT and APX, were also sensitive to continuous exposure, evidenced by a decrease in their activity. In this way, in E. densa, several enzymes involved in different metabolic pathways showed a distinct response, depending on the UV-B treatment.

  7. Phylogenomics of C(4) photosynthesis in sedges (Cyperaceae): multiple appearances and genetic convergence.

    PubMed

    Besnard, Guillaume; Muasya, A Muthama; Russier, Flavien; Roalson, Eric H; Salamin, Nicolas; Christin, Pascal-Antoine

    2009-08-01

    C(4) photosynthesis is an adaptive trait conferring an advantage in warm and open habitats. It originated multiple times and is currently reported in 18 plant families. It has been recently shown that phosphoenolpyruvate carboxylase (PEPC), a key enzyme of the C(4) pathway, evolved through numerous independent but convergent genetic changes in grasses (Poaceae). To compare the genetics of multiple C(4) origins on a broader scale, we reconstructed the evolutionary history of the C(4) pathway in sedges (Cyperaceae), the second most species-rich C(4) family. A sedge phylogeny based on two plastome genes (rbcL and ndhF) has previously identified six fully C(4) clades. Here, a relaxed molecular clock was used to calibrate this tree and showed that the first C(4) acquisition occurred in this family between 19.6 and 10.1 Ma. According to analyses of PEPC-encoding genes (ppc), at least five distinct C(4) origins are present in sedges. Two C(4) Eleocharis species, which were unrelated in the plastid phylogeny, acquired their C(4)-specific PEPC genes from a single source, probably through reticulate evolution or a horizontal transfer event. Acquisitions of C(4) PEPC in sedges have been driven by positive selection on at least 16 codons (3.5% of the studied gene segment). These sites underwent parallel genetic changes across the five sedge C(4) origins. Five of these sites underwent identical changes also in grass and eudicot C(4) lineages, indicating that genetic convergence is most important within families but that identical genetic changes occurred even among distantly related taxa. These lines of evidence give new insights into the constraints that govern molecular evolution.

  8. Ectopic expression of GsPPCK3 and SCMRP in Medicago sativa enhances plant alkaline stress tolerance and methionine content.

    PubMed

    Sun, Mingzhe; Sun, Xiaoli; Zhao, Yang; Zhao, Chaoyue; Duanmu, Huizi; Yu, Yang; Ji, Wei; Zhu, Yanming

    2014-01-01

    So far, it has been suggested that phosphoenolpyruvate carboxylases (PEPCs) and PEPC kinases (PPCKs) fulfill several important non-photosynthetic functions. However, the biological functions of soybean PPCKs, especially in alkali stress response, are not yet well known. In previous studies, we constructed a Glycine soja transcriptional profile, and identified three PPCK genes (GsPPCK1, GsPPCK2 and GsPPCK3) as potential alkali stress responsive genes. In this study, we confirmed the induced expression of GsPPCK3 under alkali stress and investigated its tissue expression specificity by using quantitative real-time PCR analysis. Then we ectopically expressed GsPPCK3 in Medicago sativa and found that GsPPCK3 overexpression improved plant alkali tolerance, as evidenced by lower levels of relative ion leakage and MDA content and higher levels of chlorophyll content and root activity. In this respect, we further co-transformed the GsPPCK3 and SCMRP genes into alfalfa, and demonstrated the increased alkali tolerance of GsPPCK3-SCMRP transgenic lines. Further investigation revealed that GsPPCK3-SCMRP co-overexpression promoted the PEPC activity, net photosynthetic rate and citric acid content of transgenic alfalfa under alkali stress. Moreover, we also observed the up-regulated expression of PEPC, CS (citrate synthase), H(+)-ATPase and NADP-ME genes in GsPPCK3-SCMRP transgenic alfalfa under alkali stress. As expected, we demonstrated that GsPPCK3-SCMRP transgenic lines displayed higher methionine content than wild type alfalfa. Taken together, results presented in this study supported the positive role of GsPPCK3 in plant response to alkali stress, and provided an effective way to simultaneously improve plant alkaline tolerance and methionine content, at least in legume crops.

  9. A possible role for C4 photosynthetic enzymes in tolerance of Zea mays to NaCl.

    PubMed

    Alla, Mamdouh M Nemat; Hassan, Nemat M

    2012-10-01

    Treatment of 14-day-old maize cultivars (Hybrid351 and Giza2) with 250 mM NaCl significantly reduced shoot fresh and dry weights and protein content during the subsequent 12 days. The magnitude of reduction was more pronounced in Giza than Hybrid. Both cultivars contained converging levels of protein for the enzymes phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), pyruvate phosphate dikinase (PPDK) and ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) under normal conditions; however, NaCl led to increase these levels in Hybrid and decrease them in Giza. Moreover, NaCl significantly inhibited the activities of PEPC, MDH and PPDK in both cultivars during the first 2 days, thereafter the inhibition nullified only in Hybrid; nonetheless, Rubisco was the least affected enzyme in both cultivars. In addition, NaCl slightly increased V (max) of PEPC, MDH and PPDK in Hybrid with no change in K (m); nevertheless V (max) dropped in Giza with an increase in K (m) of only PEPC and MDH. Also K (cat), K (cat)/K (m) and V (max)/K (m) of all enzymes were lower in treated Giza than in treated Hybrid. The increased V (max) of all enzymes in only Hybrid by NaCl confirms that they were synthesised more in Hybrid than in Giza. However, the decreased V (max) in Giza concomitant with the increased K (m) points to an interference of salinity with synthesis of enzymes and their structural integrity. This would lead to a noncompetitive inhibition for the enzymes. These findings declare that maize tolerance to NaCl was larger in Hybrid compared to Giza due to a role for C4 enzymes.

  10. Balanced allocation of organic acids and biomass for phosphorus and nitrogen demand in the fynbos legume Podalyria calyptrata.

    PubMed

    Maistry, Pravin M; Muasya, A Muthama; Valentine, Alex J; Chimphango, Samson B M

    2015-02-01

    Podalyria calyptrata is from fynbos soils with low availability of phosphorus (P) and nitrogen (N). We investigated the physiological basis for tolerance of low P supply in nodulated P. calyptrata and examined responses to increased supply of combined-N as Ca(NO3)2 and P. It was hypothesized that increasing supply of combined-N would stimulate P-acquisition mechanisms and enhance plant growth with high P supply. Biomass, leaf [N] and [P], organic acid and phosphatase root exudates, and phosphoenolpyruvate carboxylase (PEPC) and malate dehydrogenase (MDH) activity in nodules and roots were examined in two N×P experiments. Low P supply decreased leaf [P] and limited growth, decreasing the nodule:root ratio but increasing nodular PEPC and MDH activity for enhanced P-acquisition or P-utilization. At low P supply, a N-induced demand for P increased root exudation of citrate and PEPC and MDH activity in roots. Greater combined-N supply inhibited nodulation more at low P supply than at high P supply. With a P-induced demand for N the plants nodulated prolifically and increased combined-N supply did not enhance plant growth. The physiological basis for N2-fixing P. calyptrata tolerating growth at low P supply and responding to greater P supply is through balanced acquisition of P and N for plant demand.

  11. Plant, cell, and molecular mechanisms of abscisic-acid regulation of stomatal apertures. In vivo phosphorylation of phosphoenolpyruvate carboxylase in guard cells of Vicia faba L. is enhanced by fusicoccin and suppressed by abscisic acid

    SciTech Connect

    Du, Z.; Aghoram, K.; Outlaw, W.H. Jr.

    1996-12-31

    Plants regulate water loss and CO{sub 2} gain by modulating the aperture sizes of stomata that penetrate the epidermis. Aperture size itself is increased by osmolyte accumulation and consequent turgor increase in the pair of guard cells that flank each stoma. Guard-cell phosphoenolpyruvate carboxylase, which catalyzes the regulated step leading to malate synthesis, is crucial for charge and pH maintenance during osmolyte accumulation. Regulation of this cytosolic enzyme by effectors is well documented, but additional regulation by posttranslational modification is predicted by the alteration of PEPC kinetics during stomatal opening. In this study, the authors have investigated whether this alteration is associated with the phosphorylation status of this enzyme. Using sonicated epidermal peels (isolated guard cells) pre-loaded with {sub 32}PO{sub 4}, the authors induced stomatal opening and guard-cell malate accumulation by incubation with 5 {micro}M fusicoccin (FC). In corroboratory experiments, guard cells were incubated with 5 {micro}M fusicoccin (FC). In corroboratory experiments, guard cells were incubated with the FC antagonist, 10 {micro}M abscisic acid (ABA). The phosphorylation status of PEPC was assessed by immunoprecipitation, electrophoresis, immunoblotting, and autoradiography. PEPC was phosphorylated when stomata were stimulated to open, and phosphorylation was lessened by incubation with ABA.

  12. Anisakis simplex: CO(2)-fixing enzymes and development throughout the in vitro cultivation from third larval stage to adult.

    PubMed

    Dávila, Cristina; Malagón, David; Valero, Adela; Benítez, Rocío; Adroher, Francisco Javier

    2006-09-01

    We studied the effect of CO(2) on the in vitro cultivation of Anisakis simplex, an aquatic parasitic nematode of cetaceans (final hosts) and fish, squid, crustaceans and other invertebrates (intermediate/paratenic hosts), and, occasionally, of man (accidental host). The results showed that a high pCO(2), at a suitable temperature, is vital for the optimum development of these nematodes, at least from the third larval stage (L3) to adult. After 30 days cultivation in air, molting to L4 (fourth larval stage) was reduced to 1/3, while survival was about 1/3 of that when cultivated in air + 5% CO(2). The activity of the CO(2)-fixing enzymes, PEPCK and PEPC, was also studied. Throughout the development of the worms studied, PEPCK activity was much higher than that of PEPC (e.g., 305 vs. 6.8 nmol/min.mg protein, respectively, in L3 collected from the host fish). The activity of these enzymes in the worms cultivated in air + 5% CO(2) was highest during M3, and was also generally higher than that of those cultivated in air only, especially during molting from L3 to L4 (e.g., in recently molted L4, PEPCK activity was 3.7 times greater than that of PEPC 2.9 times greater than when cultivated in air).

  13. CO2-fixing enzymes and phosphoenolpyruvate metabolism in the fish parasite Hysterothylacium aduncum (Ascaridoidea, Anisakidae).

    PubMed

    Malagón, David; Benítez, Rocio; Valero, Adela; Adroher, Francisco Javier

    2009-07-23

    CO2 stimulates the development of many of the intestinal helminths that are able to fix CO2 by means of phosphoenolpyruvate carboxykinase (PEPCK), such as Hysterothylacium aduncum. We determined the activity of CO2-fixing enzymes such as PEPCK and phosphoenolpyruvate carboxylase (PEPC), although no significant activity was detected for pyruvate carboxylase or carboxylating-malic enzyme. The former act on phosphoenolpyruvate (PEP) to yield oxalacetate. In the helminths studied, PEP has a vital role in glucidic metabolism. Consequently, we determined the activity of other enzymes involved in the crossroad of PEP, such as pyruvate kinase (PK), lactate dehydrogenase and malate dehydrogenase. All enzymes detected showed significant variations in activity during the in vitro development of the parasite from the third larval stage to mature adult. Fixing of CO2 by PEPCK decreased during development (from 228 to 115 nmol min(-1) mg(-1) protein), while that by PEPC increased (from 19 to 46 nmol min(-1) mg(-1) protein). This enzyme, which is rare in animals, could play a part in detecting levels of free phosphate, releasing it from PEP when required for processes such as glycogenolysis, glycolysis and adenosine 5'-triphosphate (ATP) synthesis. PK, which showed increasing activity during development up to immature adult (from 56 to 82 nmol min(-1) mg(-1) protein), could act in combination with PEPC to obtain energy in the cytosol (in the form of ATP) and in the mitochondria (possible destination of the pyruvate formed), compensating for the decrease in activity of PEPCK.

  14. Research on 2x1 plasma electrode electro-optical switch with large aperture

    NASA Astrophysics Data System (ADS)

    Zhang, Xiong Jun; Zheng, Kui Xing; Feng, B.; Wu, D. S.; Lu, J. P.; Tian, X. L.; Jin, F.; Sui, Zhan; Wei, Xiaofeng; Zhang, Xiaomin

    2005-01-01

    In conceptual design of the prototype for SG-III facility, a full aperture electro-optical switch was placed between the cavity mirror and the main amplifier to isolate the reflected beams. The beam on the cavity mirror is 240mm×240mm square. Pockells cells of conversional design with coaxial ring electrodes can not scale to such large square aperture. In the 1980s, a plasma electrode Pockels cell (PEPC) concept was invented at LLNL. It uses transparent plasma electrode formed through gas discharge as the electrodes to apply the voltage across switching crystal to rotate the polarization of a transmitted laser beam. And it can be scaled to large aperture with thin crystal. So the switch which would be used in SG-III is based on this technology. The technical integration line as a prototype of SG-III laser is actually a 4×2 beam bundle. And the full aperture optical switch is mechanically designed four apertures as a removable unit, and electrically two 2×1 PEPC putting together. So we built a 2×1 PEPC to develop the technology first. The 2×1 PEPC is a sandwich structure made of an insulating mid plane between a pair of plasma chambers. The frame of both plasma chambers are machining in duralumin. Each chamber is installed with a planar magnetic cathode and four segments spherical anodes made from stainless steel. The cathode and anode are insulated from the housing with a special shell made from plastic, and plasma is insulated from the housing by an 80-μm-thick anodic coating on the duralumin. The two plasma chambers are separated by a mid plane of glass frame with two square holes. The two holes are filled by two electro-optical crystals with a 240-mm square aperture. With the optimized operating pressure and the electrical parameters, a very good homogeneity and low resistivity plasma electrode is obtained. Finally we tested its switching performance to simulate the case that it will be used in the SG-III prototype facility. It works with a quarter wave

  15. Thermal adaptation of cellular membranes in natural populations of Drosophila melanogaster.

    PubMed

    Cooper, Brandon S; Hammad, Loubna A; Montooth, Kristi L

    2014-08-01

    Changes in temperature disrupt the fluidity of cellular membranes, which can negatively impact membrane integrity and cellular processes. Many ectotherms, including Drosophila melanogaster (Meigen), adjust the glycerophospholipid composition of their membranes to restore optimal fluidity when temperatures change, a type of trait plasticity termed homeoviscous adaptation.Existing data suggest that plasticity in the relative abundances of the glycerophospholipids phosphatidylethanolamine (PE) and phosphatidylcholine (PC) underlies cellular adaptation to temporal variability in the thermal environment. For example, laboratory populations of D. melanogaster evolved in the presence of temporally variable temperatures have greater developmental plasticity of the ratio of PE to PC (PE/PC) and greater fecundity than do populations evolved at constant temperatures.Here, we extend this work to natural populations of D. melanogaster by evaluating thermal plasticity of glycerophospholipid composition at different life stages, in genotypes isolated from Vermont, Indiana and North Carolina, USA. We also quantify the covariance between developmental and adult (reversible) plasticity, and between adult responses of the membrane to cool and warm thermal shifts.As predicted by physiological models of homeoviscous adaptation, flies from all populations decrease PE/PC and the degree of lipid unsaturation in response to warm temperatures. Furthermore, these populations have diverged in their degree of membrane plasticity. Flies from the most variable thermal environment (Vermont, USA) decrease PE/PC to a greater extent than do other populations when developed at a warm temperature, a pattern that matches our previous observation in laboratory-evolved populations. We also find that developmental plasticity and adult plasticity of PE/PC covary across genotypes, but that adult responses to cool and warm thermal shifts do not.When combined with our previous observations of laboratory

  16. Discrimination in the dark. Resolving the interplay between metabolic and physical constraints to phosphoenolpyruvate carboxylase activity during the crassulacean acid metabolism cycle.

    PubMed

    Griffiths, Howard; Cousins, Asaph B; Badger, Murray R; von Caemmerer, Susanne

    2007-02-01

    A model defining carbon isotope discrimination (delta13C) for crassulacean acid metabolism (CAM) plants was experimentally validated using Kalanchoe daigremontiana. Simultaneous measurements of gas exchange and instantaneous CO2 discrimination (for 13C and 18O) were made from late photoperiod (phase IV of CAM), throughout the dark period (phase I), and into the light (phase II). Measurements of CO2 response curves throughout the dark period revealed changing phosphoenolpyruvate carboxylase (PEPC) capacity. These systematic changes in PEPC capacity were tracked by net CO2 uptake, stomatal conductance, and online delta13C signal; all declined at the start of the dark period, then increased to a maximum 2 h before dawn. Measurements of delta13C were higher than predicted from the ratio of intercellular to external CO2 (p(i)/p(a)) and fractionation associated with CO2 hydration and PEPC carboxylations alone, such that the dark period mesophyll conductance, g(i), was 0.044 mol m(-2) s(-1) bar(-1). A higher estimate of g(i) (0.085 mol m(-2) s(-1) bar(-1)) was needed to account for the modeled and measured delta18O discrimination throughout the dark period. The differences in estimates of g(i) from the two isotope measurements, and an offset of -5.5 per thousand between the 18O content of source and transpired water, suggest spatial variations in either CO2 diffusion path length and/or carbonic anhydrase activity, either within individual cells or across a succulent leaf. Our measurements support the model predictions to show that internal CO2 diffusion limitations within CAM leaves increase delta13C discrimination during nighttime CO2 fixation while reducing delta13C during phase IV. When evaluating the phylogenetic distribution of CAM, carbon isotope composition will reflect these diffusive limitations as well as relative contributions from C3 and C4 biochemistry.

  17. Photodarkening effect and optical properties of a nanocomposite material polymer/Fe3O4 magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Laikhtman, A.; Harea, D.; Axelevitch, A.; Meshalkin, A.

    2016-02-01

    Materials with combined ferroelectric and ferromagnetic properties or magneto-electric coupling effects are promising candidates for information technology, photosensoring, and device fabrication. Preparation and characterization of multiferroic materials in which ferroelectricity and ferromagnetism coexist attracted much interest in research for functionalized materials and devices. They present a possibility to electrically control magnetic memory devices and, conversely, magnetically manipulate electric devices. In this work we considered Fe3O4 magnetic nanoparticles with and without a protective SiO2/TiO2 double-layer coating embedded into the carbazole-based, namely, polyepoxypropylcarbazole (PEPC) thin (500 nm) film. Optical characterization of the PEPC films was performed using light irradiation in the UV/VIS and NIR ranges. A shift in the optical absorption edge toward a higher wavelength region of the spectrum took place for all irradiated samples: the polymer film, as well as for the samples with Fe3O4 and Fe3O4/SiO2/TiO2 nanoparticles inside of the polymer matrix. We suggest that changes in the UV/VIS/NIR spectra took place as a function of the degree of structural changes and stabilizing of the atomic matrix, as well as due to change in the values of the refractive index following irradiation, calculated from the spectral data. In such a way photo-structural modifications induced by the UV irradiation and the implantation of the magnetic nanoparticles make these materials perspective for optical recording media. We conclude, therefore, that Fe3O4 and Fe3O4/SiO2/TiO2 nanoparticles considerably affect the optical properties of the PEPC thin film, and result in the enhancement of the photodarkening effect following the UV irradiation.

  18. Photosynthetic pathway diversity in a seasonal pool community

    USGS Publications Warehouse

    Keeley, Jon E.

    1999-01-01

    1. Photosynthetic pathway diversity was evaluated for the dominant species in a seasonally aquatic community in the south-western USA using 14C pulse-chase techniques.2. Under submerged conditions, only about half of the species were clearly C3, three of the 15 dominants were CAM, one species was C4 and three were potentially assimilating carbon with both C3 and C4 fixation.3. During the brief terrestrial stage in the life history of these amphibious plants, both the CAM and the C3 + C4 species switched to C3, whereas the C4 species did not switch.4. Numerous variations were apparent; for example, the C4 species, while exhibiting a biochemical pathway indistinguishable from terrestrial C4 plants, lacked Kranz anatomy in the aquatic foliage. Also, despite well-developed CAM in several species, others exhibited low-level diel changes in acidity, apparently not indicative of CAM.5. Species with C4 or CAM CO2 concentrating mechanisms lacked the capacity for bicarbonate uptake, an alternative CO2 concentrating mechanism found in certain C3 species in this community.6. Rubisco/PEPC in aquatic foliage was higher in C3 species than in C4, CAM or putative C3 + C4species. In the terrestrial phase, as expected, the switch from CAM or C3 + C4 to strictly C3assimilation was associated with a substantial increase in Rubisco/PEPC. Quite unexpected, however, was the substantial increase in this ratio in terrestrial C3 foliage. It is hypothesized that submerged C3 plants utilize PEPC for recycling of respiratory CO2 and/or C4 phototrophism under field conditions of limited CO2 and O2 saturation, and this is lost in the terrestrial foliage.

  19. Vacuum Brazing of Beryllium Copper Components for the National Ignition Facility

    SciTech Connect

    Tyhurst, C.C.; Cunningham, M.A.

    2002-06-04

    A process for vacuum brazing beryllium copper anode assemblies was required for the Plasma Electrode Pockels Cell System, or PEPC, a component for the National Ignition Facility (NIF). Initial problems with the joint design and wettability of the beryllium copper drove some minor design changes. Brazing was facilitated by plating the joint surface of the beryllium copper rod with silver 0.0006 inch thick. Individual air sampling during processing and swipe tests of the furnace interior after brazing revealed no traceable levels of beryllium.

  20. Primers for phylogeny reconstruction in Bignonieae (Bignoniaceae) using herbarium samples1

    PubMed Central

    Zuntini, Alexandre R.; Fonseca, Luiz Henrique M.; Lohmann, Lúcia G.

    2013-01-01

    • Premise of the study: New primers were developed for Bignonieae to enable phylogenetic studies within this clade using herbarium samples. • Methods and Results: Internal primers were designed based on available sequences of the plastid ndhF gene and the rpl32-trnL intergenic spacer region, and the nuclear gene PepC. The resulting primers were used to amplify DNA extracted from herbarium materials. High-quality data were obtained from herbarium samples up to 53 yr old. • Conclusions: The standardized methodology allows the inclusion of herbarium materials as alternative sources of DNA for phylogenetic studies in Bignonieae. PMID:25202586

  1. NIF Periscope Wall Modal Study Comparison of Results for 2 FEA Models with 2 Modal Tests

    SciTech Connect

    Eli, M W; Gerhard, M A; Lee, C L; Sommer, S C; Woehrle, T G

    2000-10-26

    This report summarizes experimentally and numerically determined modal properties for one of the reinforced concrete end walls of the NIF Periscope Support Structure in Laser Bay 1. Two methods were used to determine these modal properties: (1) Computational finite-element analyses (modal extraction process); and (2) Experimental modal analysis based on measured test data. This report also includes experimentally determined modal properties for a prototype LM3/Polarizer line-replaceable unit (LRU) and a prototype PEPC LRU. Two important parameters, used during the design phase, are validated through testing [ref 1]. These parameters are the natural frequencies and modal damping (of the system in question) for the first several global modes of vibration. Experimental modal testing provides these modal values, along with the corresponding mode shapes. Another important parameter, the input excitation (expected during normal operation of the NIF laser system) [ref 1], can be verified by performing a series of ambient vibration measurements in the vicinity of the particular system (or subsystem) of interest. The topic of ambient input excitation will be covered in a separate report. Due to the large mass of the Periscope Pedestal, it is difficult to excite the entire series of Periscope Pedestal Walls all at once. It was decided that the experimental modal tests would be performed on just one Periscope End Wall in Laser Bay 1. Experimental modal properties for the Periscope End Wall have been used to validate and update the FE analyses. Results from the analyses and modal tests support the conclusion that the Periscope Pedestal will not exceed the stability budget, which is described in reference 1. The results of the modal tests for the Periscope End Wall in Laser Bay 1 have provided examples of modal properties that can be derived from future modal tests of the entire Periscope Assembly (excluding the LRU's). This next series of larger modal tests can be performed

  2. A humidity sensing organic-inorganic composite for environmental monitoring.

    PubMed

    Ahmad, Zubair; Zafar, Qayyum; Sulaiman, Khaulah; Akram, Rizwan; Karimov, Khasan S

    2013-03-14

    In this paper, we present the effect of varying humidity levels on the electrical parameters and the multi frequency response of the electrical parameters of an organic-inorganic composite (PEPC+NiPc+Cu2O)-based humidity sensor. Silver thin films (thickness ~200 nm) were primarily deposited on plasma cleaned glass substrates by the physical vapor deposition (PVD) technique. A pair of rectangular silver electrodes was formed by patterning silver film through standard optical lithography technique. An active layer of organic-inorganic composite for humidity sensing was later spun coated to cover the separation between the silver electrodes. The electrical characterization of the sensor was performed as a function of relative humidity levels and frequency of the AC input signal. The sensor showed reversible changes in its capacitance with variations in humidity level. The maximum sensitivity ~31.6 pF/%RH at 100 Hz in capacitive mode of operation has been attained. The aim of this study was to increase the sensitivity of the previously reported humidity sensors using PEPC and NiPc, which has been successfully achieved.

  3. A Humidity Sensing Organic-Inorganic Composite for Environmental Monitoring

    PubMed Central

    Ahmad, Zubair; Zafar, Qayyum; Sulaiman, Khaulah; Akram, Rizwan; Karimov, Khasan S.

    2013-01-01

    In this paper, we present the effect of varying humidity levels on the electrical parameters and the multi frequency response of the electrical parameters of an organic-inorganic composite (PEPC+NiPc+Cu2O)-based humidity sensor. Silver thin films (thickness ∼200 nm) were primarily deposited on plasma cleaned glass substrates by the physical vapor deposition (PVD) technique. A pair of rectangular silver electrodes was formed by patterning silver film through standard optical lithography technique. An active layer of organic-inorganic composite for humidity sensing was later spun coated to cover the separation between the silver electrodes. The electrical characterization of the sensor was performed as a function of relative humidity levels and frequency of the AC input signal. The sensor showed reversible changes in its capacitance with variations in humidity level. The maximum sensitivity ∼31.6 pF/%RH at 100 Hz in capacitive mode of operation has been attained. The aim of this study was to increase the sensitivity of the previously reported humidity sensors using PEPC and NiPc, which has been successfully achieved. PMID:23493124

  4. Synergic effect of salinity and CO2 enrichment on growth and photosynthetic responses of the invasive cordgrass Spartina densiflora

    PubMed Central

    Mateos-Naranjo, Enrique; Redondo-Gómez, Susana; Álvarez, Rosario; Cambrollé, Jesús; Gandullo, Jacinto; Figueroa, M. Enrique

    2010-01-01

    Spartina densiflora is a C4 halophytic species that has proved to have a high invasive potential which derives from its clonal growth and its physiological plasticity to environmental factors, such as salinity. A greenhouse experiment was designed to investigate the synergic effect of 380 and 700 ppm CO2 at 0, 171, and 510 mM NaCl on the growth and the photosynthetic apparatus of S. densiflora by measuring chlorophyll fluorescence parameters, gas exchange and photosynthetic pigment concentrations. PEPC activity and total ash, sodium, potassium, calcium, magnesium, and zinc concentrations were determined, as well as the C/N ratio. Elevated CO2 stimulated growth of S. densiflora at 0 and 171 mM NaCl external salinity after 90 d of treatment. This growth enhancement was associated with a greater leaf area and improved leaf water relations rather than with variations in net photosynthetic rate (A). Despite the fact that stomatal conductance decreased in response to 700 ppm CO2 after 30 d of treatment, A was not affected. This response of A to elevated CO2 concentration might be explained by an enhanced PEPC carboxylation capacity. On the whole, plant nutrient concentrations declined under elevated CO2, which can be ascribed to the dilution effect caused by an increase in biomass and the higher water content found at 700 ppm CO2. Finally, CO2 and salinity had a marked overall effect on the photochemical (PSII) apparatus and the synthesis of photosynthetic pigments. PMID:20194923

  5. Acclimation of Biochemical and Diffusive Components of Photosynthesis in Rice, Wheat, and Maize to Heat and Water Deficit: Implications for Modeling Photosynthesis

    PubMed Central

    Perdomo, Juan A.; Carmo-Silva, Elizabete; Hermida-Carrera, Carmen; Flexas, Jaume; Galmés, Jeroni

    2016-01-01

    The impact of the combined effects of heat stress, increased vapor pressure deficit (VPD) and water deficit on the physiology of major crops needs to be better understood to help identifying the expected negative consequences of climate change and heat waves on global agricultural productivity. To address this issue, rice, wheat, and maize plants were grown under control temperature (CT, 25°C, VPD 1.8 kPa), and a high temperature (HT, 38°C, VPD 3.5 kPa), both under well-watered (WW) and water deficit (WD) conditions. Gas-exchange measurements showed that, in general, WD conditions affected the leaf conductance to CO2, while growth at HT had a more marked effect on the biochemistry of photosynthesis. When combined, HT and WD had an additive effect in limiting photosynthesis. The negative impacts of the imposed treatments on the processes governing leaf gas-exchange were species-dependent. Wheat presented a higher sensitivity while rice and maize showed a higher acclimation potential to increased temperature. Rubisco and PEPC kinetic constants determined in vitro at 25°C and 38°C were used to estimate Vcmax, Jmax, and Vpmax in the modeling of C3 and C4 photosynthesis. The results here obtained reiterate the need to use species-specific and temperature-specific values for Rubisco and PEPC kinetic constants for a precise parameterization of the photosynthetic response to changing environmental conditions in different crop species. PMID:27920782

  6. Different Growth and Physiological Responses to Cadmium of the Three Miscanthus Species

    PubMed Central

    Guo, Haipeng; Hong, Chuntao; Chen, Xiaomin; Xu, Yanxia; Liu, Yan; Jiang, Dean; Zheng, Bingsong

    2016-01-01

    Miscanthus has been proposed as a promising crop for phytoremediation due to its high biomass yield and remarkable adaptability to different environments. However, little is known about the resistance of Miscanthus spp. to cadmium (Cd). To determine any differences in resistance of Miscanthus to Cd, we examined plant growth, net photosynthetic rate (Pn), activities of anti-oxidant and C4 photosynthetic enzymes, concentrations of Cd in leaves and roots, and observed the chloroplast structure in three Miscanthus species treated with 0, 10, 50, 100 or 200 μM Cd in solutions. Miscanthus sinensis showed more sensitivity to Cd, including sharp decreases in growth, Pn, PEPC activity and damage to chloroplast structure, and the highest H2O2 and Cd concentrations in leaves and roots after Cd treatments. Miscanthus sacchariflorus showed higher resistance to Cd and better growth, had the highest Pn and phosphoenolpyruvate carboxylase (PEPC) activities and integrative chloroplast structure and the lowest hydrogen peroxide (H2O2) and leaf and root Cd concentrations. The results could play an important role in understanding the mechanisms of Cd tolerance in plants and in application of phytoremediation. PMID:27070918

  7. Invasion percolation between two sites in two, three, and four dimensions

    NASA Astrophysics Data System (ADS)

    Lee, Sang Bub

    2009-06-01

    The mass distribution of invaded clusters in non-trapping invasion percolation between an injection site and an extraction site has been studied, in two, three, and four dimensions. This study is an extension of the recent study focused on two dimensions by Araújo et al. [A.D. Araújo, T.F. Vasconcelos, A.A. Moreira, L.S. Lucena, J.S. Andrade Jr., Phys. Rev. E 72 (2005) 041404] with respect to higher dimensions. The mass distribution exhibits a power-law behavior, P(m)∝m. It has been found that the index α for pe, pc being the percolation threshold of a regular percolation, appears to be independent of the value of pe and is also independent of the lattice dimensionality. When pe=pc, α appears to depend marginally on the lattice dimensionality, and the relation α=τ-1, τ being the exponent associated with cluster size distribution of a regular percolation via ns∝s, appears to be valid.

  8. DEVELOPMENT OF SOLID-STATE DRIVERS FOR THE NIF PLASMA ELECTRODE POCKELS CELL

    SciTech Connect

    Barbosa, F; Arnold, P A; McHale, G B; James, G; Brown, G; Cook, E G; Hickman, B C

    2008-05-14

    Large aperture Plasma Electrode Pockels Cells (PEPC) are an enabling technology in the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. The Pockels cell allows the NIF laser to take advantage of multipass amplifier architecture, thus reducing costs and physical size of the facility. Each Pockels cell comprises four 40-cm x 40-cm apertures arranged in a 4 x 1 array. The combination of the Pockels cell and a thin-film polarizer, configured in a 4 x 1 array, form an optical switch that is key to achieving multi-pass operation. Solid-state Plasma Pulse Generators (PPGs) and high current high voltage solid-state Switch Pulse Generators (SPGs) have been developed for use in the PEPC. The solid-state plasma pulse generators initiate and maintain plasma within the cells; each pulser is capable of delivering 60J of energy to each plasma channel. Deployment of the solid-state PPGs has been completed in NIF. The MOSFET-switched SPG is capable of delivering a requisite fast rise time, 17kV flattop pulse to the cells nonlinear crystals. A complete software and hardware control system has been developed and is currently being tested for use on the solid-state SPGs. Also a transmission line modeling, development, and testing effort is in process, in support of NIFs Advanced Radiographic Capabilities (ARC). Work is scheduled for completion by the end of the calendar year.

  9. Occurrence of a number of enzymes involved in either gluconeogenesis or other processes in the pericarp of three cultivars of grape (Vitis vinifera L.) during development.

    PubMed

    Famiani, Franco; Moscatello, Stefano; Ferradini, Nicoletta; Gardi, Tiziano; Battistelli, Alberto; Walker, Robert P

    2014-11-01

    It is uncertain whether the enzymes pyruvate orthophosphate dikinase (PPDK) or isocitrate lyase (ICL) are present in the pericarp of grape, in which they could function in gluconeogenesis. The occurrence of these and other enzymes was investigated in the pericarp of three cultivars of grape (Vitis vinifera L.). In particular, the abundance of the enzymes aldolase, glutamine synthase (GS), acid invertase, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEPC), PPDK and ICL were determined during the development of the pericarp of the cultivars Cabernet Sauvignon, Chardonnay and Zibibbo. PPDK and ICL were not detected at any stage of development. Each of the other enzymes showed different changes in abundance during development. However, for a given enzyme its changes in abundance were similar in each cultivar. In the ripe pericarp of Cabernet Sauvignon, PEPC, cytosolic GS and aldolase were equally distributed between the vasculature and parenchyma cells of the flesh and skin. The absence or very low abundance of PPDK provides strong evidence that any gluconeogenesis from malate utilises phosphoenolpyruvate carboxykinase (PEPCK). The absence or very low abundance of ICL in the pericarp precludes any gluconeogenesis from ethanol.

  10. Production of marker-free transgenic Jatropha curcas expressing hybrid Bacillus thuringiensis δ-endotoxin Cry1Ab/1Ac for resistance to larvae of tortrix moth (Archips micaceanus)

    PubMed Central

    2014-01-01

    Background The potential biofuel plant Jatropha curcas L. is affected by larvae of Archips micaceanus (Walker), a moth of the family Tortricidae. The hybrid Bacillus thuringiensis (Bt) δ-endotoxin protein Cry1Ab/1Ac confers resistance to lepidopteran insects in transgenic rice. Results Here, we report the production of a marker-free transgenic line of J. curcas (L10) expressing Cry1Ab/1Ac using Agrobacterium-mediated transformation and a chemically regulated, Cre/loxP-mediated DNA recombination system. L10 carries a single copy of marker-free T-DNA that contains the Cry1Ab/1Ac gene under the control of a maize phosphoenolpyruvate carboxylase gene promoter (P Pepc :Cry1Ab/1Ac:T Nos ). The P Pepc :Cry1Ab/1Ac:T Nos gene was highly expressed in leaves of L10 plants. Insecticidal bioassays using leaf explants of L10 resulted in 80-100% mortality of larvae of A. micaceanus at 4 days after infestation. Conclusion The results demonstrate that the hybrid Bt δ-endotoxin protein Cry1Ab/1Ac expressed in Jatropha curcas displays strong insecticidal activity to A. micaceanus. The marker-free transgenic J. curcas line L10 can be used for breeding of insect resistance to A. micaceanus. PMID:24808924

  11. Synergic effect of salinity and CO2 enrichment on growth and photosynthetic responses of the invasive cordgrass Spartina densiflora.

    PubMed

    Mateos-Naranjo, Enrique; Redondo-Gómez, Susana; Alvarez, Rosario; Cambrollé, Jesús; Gandullo, Jacinto; Figueroa, M Enrique

    2010-06-01

    Spartina densiflora is a C(4) halophytic species that has proved to have a high invasive potential which derives from its clonal growth and its physiological plasticity to environmental factors, such as salinity. A greenhouse experiment was designed to investigate the synergic effect of 380 and 700 ppm CO(2) at 0, 171, and 510 mM NaCl on the growth and the photosynthetic apparatus of S. densiflora by measuring chlorophyll fluorescence parameters, gas exchange and photosynthetic pigment concentrations. PEPC activity and total ash, sodium, potassium, calcium, magnesium, and zinc concentrations were determined, as well as the C/N ratio. Elevated CO(2) stimulated growth of S. densiflora at 0 and 171 mM NaCl external salinity after 90 d of treatment. This growth enhancement was associated with a greater leaf area and improved leaf water relations rather than with variations in net photosynthetic rate (A). Despite the fact that stomatal conductance decreased in response to 700 ppm CO(2) after 30 d of treatment, A was not affected. This response of A to elevated CO(2) concentration might be explained by an enhanced PEPC carboxylation capacity. On the whole, plant nutrient concentrations declined under elevated CO(2), which can be ascribed to the dilution effect caused by an increase in biomass and the higher water content found at 700 ppm CO(2). Finally, CO(2) and salinity had a marked overall effect on the photochemical (PSII) apparatus and the synthesis of photosynthetic pigments.

  12. Proline synthesis in barley under iron deficiency and salinity.

    PubMed

    Arias-Baldrich, Cirenia; Bosch, Nadja; Begines, Digna; Feria, Ana B; Monreal, José A; García-Mauriño, Sofía

    2015-07-01

    This work investigates proline synthesis in six barley varieties subjected to iron deficiency, salinity or both stresses. The highest growth under Fe sufficiency corresponded to Belgrano and Shakira. A moderate augment of leaf phosphoenolpyruvate carboxylase (PEPC) activity was observed in all six varieties in response to Fe deficiency, consistently in leaves and sporadically in roots. All six varieties accumulated proline under Fe deficiency, to a higher extent in leaves than in roots. The decrease of Fe supply from 100 μM NaFe(III)-EDTA to 0.5 μM NaFe(III)-EDTA reduced growth and photosynthetic pigments similarly in the six barley varieties. On the contrary, differences between varieties could be observed with respect to increased or, conversely, decreased proline content as a function of the amount of NaFe(III)-EDTA supplied. These two opposite types were represented by Belgrano (higher proline under Fe deficiency) and Shakira (higher proline under Fe sufficiency). Time-course experiments suggested that leaf PEPC activity was not directly responsible for supplying C for proline synthesis under Fe deficiency. High proline levels in the leaves of Fe-deficient Belgrano plants in salinity were associated to a better performance of this variety under these combined stresses.

  13. The nature of the CO2 -concentrating mechanisms in a marine diatom, Thalassiosira pseudonana.

    PubMed

    Clement, Romain; Dimnet, Laura; Maberly, Stephen C; Gontero, Brigitte

    2016-03-01

    Diatoms are widespread in aquatic ecosystems where they may be limited by the supply of inorganic carbon. Their carbon dioxide-concentrating mechanisms (CCMs) involving transporters and carbonic anhydrases (CAs) are well known, but the contribution of a biochemical CCM involving C4 metabolism is contentious. The CCM(s) present in the marine-centric diatom, Thalassiosira pseudonana, were studied in cells exposed to high or low concentrations of CO2 , using a range of approaches. At low CO2 , cells possessed a CCM based on active uptake of CO2 (70% contribution) and bicarbonate, while at high CO2 , cells were restricted to CO2 . CA was highly and rapidly activated on transfer to low CO2 and played a key role because inhibition of external CA produced uptake kinetics similar to cells grown at high CO2 . The activities of phosphoenolpyruvate (PEP) carboxylase (PEPC) and the PEP-regenerating enzyme, pyruvate phosphate dikinase (PPDK), were lower in cells grown at low than at high CO2 . The ratios of PEPC and PPDK to ribulose bisphosphate carboxylase were substantially lower than 1, even at low CO2 . Our data suggest that the kinetic properties of this species results from a biophysical CCM and not from C4 type metabolism.

  14. 30 CFR 20.7 - Specific requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... lamps, inspection lamps, flashlights, and animal lamps which are operated by small storage batteries or dry cells. (b) Class 2. Class 2 includes lamps such as the pneumatic-electric types and large...

  15. 30 CFR 20.7 - Specific requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... lamps, inspection lamps, flashlights, and animal lamps which are operated by small storage batteries or dry cells. (b) Class 2. Class 2 includes lamps such as the pneumatic-electric types and large...

  16. 30 CFR 20.7 - Specific requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... lamps, inspection lamps, flashlights, and animal lamps which are operated by small storage batteries or dry cells. (b) Class 2. Class 2 includes lamps such as the pneumatic-electric types and large...

  17. A kinetic study of the effects of phosphate and organic phosphates on the activity of phosphoenolpyruvate carboxylase from Crassula argentea.

    PubMed

    Meyer, C R; Rustin, P; Wedding, R T

    1989-05-15

    The effects of phosphate and several phosphate-containing compounds on the activity of purified phosphoenolpyruvate carboxylase (PEPC) from the crassulacean acid metabolism plant, Crassula argentea, were investigated. When assayed at subsaturating phosphoenolpyruvate (PEP) concentrations, low concentrations of most of the compounds tested were found to stimulate PEPC activity. This activation, variable in extent, was found in all cases to be competitive with glucose 6-phosphate (Glc-6-P) stimulation, suggesting that these effectors bind to the Glc-6-P site. At higher concentrations, depending upon the effector molecule studied, deactivation, inhibition, or no response was observed. More detailed studies were performed with Glc-6-P, AMP, phosphoglycolate, and phosphate. AMP had previously been shown to be a specific ligand for the Glc-6-P site. The main effect of Glc-6-P and AMP on the kinetic parameters was to decrease the apparent Km and increase Vmax/Km. AMP also caused a decrease in the Vmax of the reaction. In contrast, phosphoglycolate acted essentially as a competitive inhibitor increasing the apparent Km for PEP and decreasing Vmax/Km. Inorganic phosphate had a biphasic effect on the kinetic parameters, resulting in a transient decrease in Km followed by an increase of the apparent Km for PEP with increasing concentration of phosphate. The Vmax also was decreased with increasing phosphate concentrations. Further, the enzyme appeared to respond to the complex of phosphate with magnesium. In the presence of a saturating concentration of AMP, no activation but rather inhibition was observed with increasing phosphate concentration. This is consistent with the binding of phosphate to two separate sites--the Glc-6-P activation site and an inhibitory site, a phenomenon that may be occurring with other phosphate containing compounds. High concentrations of phosphate with magnesium were found to protect enzyme activity when PEPC, previously shown to contain an

  18. Changes in gravity affect gene expression, protein modulation and metabolite pools of arabidopsis

    NASA Astrophysics Data System (ADS)

    Hampp, R.; Martzivanou, M.; Maier, R. M.; Magel, E.

    Callus cultures of Arabidopsis thaliana (cv. Columbia) in Petri dishes / suspension cultures were exposed to altered g-forces by centrifugation (1 to 10 g), klinorotation, and μ g (sounding rocket flights). Using semi-quantitative RT-PCR, transcripts of genes coding for metabolic key enzymes (ADP-glucose pyrophosphorylase, ADPG-PP; ß-amylase, fructose-1,6-bisphosphatase, FBPase; glyceraldehyde-P dehydrogenase, GAPDH; hydroxymethylglutaryl-CoA reductase, HMG; phenylalanine-ammonium-lyase, PAL; PEP carboxylase, PEPC) were used to monitor threshold conditions for g-number (all) and time of exposure (ß-amylase) which led to altered amounts of the gene product. Exposure to approx. 5 g and higher for 1h resulted in altered transcript levels: transcripts of ß-amylase, PAL, and PEPC were increased, those of ADPG-PP decreased, while those of FBPase, GAPDH, and HMG were not affected. This probably indicates a shift from starch synthesis to starch degradation and increased rates of anaplerosis (PEPC: supply of ketoacids for amino acid synthesis). In order to get more information about g-related effects on gene expression, we used a 1h-exposure to 7 g for a microarray analysis. Transcripts of more than 200 genes were significantly increased in amount (ratio 7g / 1g control; 21.6 and larger). They fall into several categories. Transcripts coding for enzymes of major pathways form the largest group (25%), followed by gene products involved in cellular organisation and cell wall formation / rearrangement (17%), signalling, phosphorylation/dephosphorylation (12%), proteolysis and transport (10% each), hormone synthesis plus related events (8%), defense (4%), stress-response (2%), and gravisensing (2%). Many of the alterations are part of a general stress response, but some changes related to the synthesis / rearrangement of cell wall components could be more hyper-g-specific. Using macroarrays with selected genes according to our hypergravity study (metabolism / signalling

  19. Photosynthetic flexibility in maize exposed to salinity and shade

    PubMed Central

    Sharwood, Robert E.; Sonawane, Balasaheb V.; Ghannoum, Oula

    2014-01-01

    C4 photosynthesis involves a close collaboration of the C3 and C4 metabolic cycles across the mesophyll and bundle-sheath cells. This study investigated the coordination of C4 photosynthesis in maize plants subjected to two salinity (50 and 100mM NaCl) treatments and one shade (20% of full sunlight) treatment. Photosynthetic efficiency was probed by combining leaf gas-exchange measurements with carbon isotope discrimination and assaying the key carboxylases [ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [nicotinamide adenine dinucleotide phosphate malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] operating in maize leaves. Generally, salinity inhibited plant growth and photosynthesis to a lesser extent than shade. Salinity reduced photosynthesis primarily by reducing stomatal conductance and secondarily by equally reducing Rubisco and PEPC activities; the decarboxylases were inhibited more than the carboxylases. Salinity increased photosynthetic carbon isotope discrimination (Δp) and reduced leaf dry-matter carbon isotope composition (13δ) due to changes in p i/p a (intercellular to ambient CO2 partial pressure), while CO2 leakiness out of the bundle sheath (ϕ) was similar to that in control plants. Acclimation to shade was underpinned by a greater downregulation of PEPC relative to Rubisco activity, and a lesser inhibition of NADP-ME (primary decarboxylase) relative to PEP-CK (secondary decarboxylase). Shade reduced Δp and ɸ without significantly affecting leaf 13δ or p i/p a relative to control plants. Accordingly, shade perturbed the balance between the C3 and C4 cycles during photosynthesis in maize, and demonstrated the flexible partitioning of C4 acid decarboxylation activity between NADP-ME and PEP-CK in response to the environment. This study highlights the need to improve our understanding of the links between leaf 13δ and photosynthetic Δp, and the role

  20. Re-examination of the roles of PEP and Mg2+ in the reaction catalysed by the phosphorylated and non-phosphorylated forms of phosphoenolpyruvate carboxylase from leaves of Zea mays. Effects of the activators glucose 6-phosphate and glycine.

    PubMed Central

    Tovar-Méndez, A; Rodríguez-Sotres, R; López-Valentín, D M; Muñoz-Clares, R A

    1998-01-01

    To study the effects of phosphoenolpyruvate (PEP) and Mg2+ on the activity of the non-phosphorylated and phosphorylated forms of phosphoenolpyruvate carboxylase (PEPC) from Zea mays leaves, steady-state measurements have been carried out with the free forms of PEP (fPEP) and Mg2+ (fMg2+), both in a near-physiological concentration range. At pH 7.3, in the absence of activators, the initial velocity data obtained with both forms of the enzyme are consistent with the exclusive binding of MgPEP to the active site and of fPEP to an activating allosteric site. At pH 8.3, and in the presence of saturating concentrations of glucose 6-phosphate (Glc6P) or Gly, the free species also combined with the active site in the free enzyme, but with dissociation constants at least 35-fold that estimated for MgPEP. The latter dissociation constant was lowered to the same extent by saturating Glc6P and Gly, to approx. one-tenth and one-sixteenth in the non-phosphorylated and phosphorylated enzymes respectively. When Glc6P is present, fPEP binds to the active site in the free enzyme better than fMg2+, whereas the metal ion binds better in the presence of Gly. Saturation of the enzyme with Glc6P abolished the activation by fPEP, consistent with a common binding site, whereas saturation with Gly increased the affinity of the allosteric site for fPEP. Under all the conditions tested, our results suggest that fPEP is not able to combine with the allosteric site in the free enzyme, i.e. it cannot combine until after MgPEP, fPEP or fMg2+ are bound at the active site. The physiological role of Mg2+ in the regulation of the enzyme is only that of a substrate, mainly as part of the MgPEP complex. The kinetic properties of maize leaf PEPC reported here are consistent with the enzyme being well below saturation under the physiological concentrations of fMg2+ and PEP, particularly during the dark period; it is therefore suggested that the basal PEPC activity in vivo is very low, but highly

  1. Activities of principal photosynthetic enzymes in green macroalga Ulva linza: functional implication of C₄ pathway in CO₂ assimilation.

    PubMed

    Xu, Jianfang; Zhang, Xiaowen; Ye, Naihao; Zheng, Zhou; Mou, Shanli; Dong, Meitao; Xu, Dong; Miao, Jinlai

    2013-06-01

    The green-tide-forming macroalga Ulva linza was profiled by transcriptome sequencing to ascertain whether the alga carries both C3 and C4 photosynthesis genes. The key enzymes involved in C4 metabolism including pyruvate orthophosphate dikinase (PPDK), phosphoenolpyruvate carboxylase (PEPC), and phosphoenolpyruvate carboxykinase (PCK) were found. When measured under normal and different stress conditions, expression of rbcL was higher under normal conditions and lower under the adverse conditions, whereas that of PPDK was higher under some adverse conditions, namely desiccation, high salinity, and low salinity. Both ribulose-1, 5-biphosphate carboxylase (RuBPCase) and PPDK were found to play a role in carbon fixation, with significantly higher PPDK activity across the stress conditions. These results suggest that elevated PPDK activity alters carbon metabolism in U. linza leading to partial operation of the C4 carbon metabolism, a pathway that, under stress conditions, probably contributes to the hardy character of U. linza and thus to its wide distribution.

  2. A HIGH CURRENT, HIGH VOLTAGE SOLID-STATE PULSE GENERATOR FOR THE NIF PLASMA ELECTRODE POCKELS CELL

    SciTech Connect

    Arnold, P A; Barbosa, F; Cook, E G; Hickman, B C; Akana, G L; Brooksby, C A

    2007-07-27

    A high current, high voltage, all solid-state pulse modulator has been developed for use in the Plasma Electrode Pockels Cell (PEPC) subsystem in the National Ignition Facility. The MOSFET-switched pulse generator, designed to be a more capable plug-in replacement for the thyratron-switched units currently deployed in NIF, offers unprecedented capabilities including burst-mode operation, pulse width agility and a steady-state pulse repetition frequency exceeding 1 Hz. Capable of delivering requisite fast risetime, 17 kV flattop pulses into a 6 {Omega} load, the pulser employs a modular architecture characteristic of the inductive adder technology, pioneered at LLNL for use in acceleration applications, which keeps primary voltages low (and well within the capabilities of existing FET technology), reduces fabrication costs and is amenable to rapid assembly and quick field repairs.

  3. Problems of rapid digitalization in severe congestive heart failure.

    PubMed

    Haustein, K O; Assmann, I; Fiehring, H

    1980-02-01

    The pharmacodynamic effects (changes of systolic time intervals, STI, reaction of pulmonary arterial pressure) of digitoxin were studied in 7 patients with severe congestive heart failure in comparison with the corresponding plasma level. STI indicated glycoside-dependent changes, i.e. shortening of LVETc and QS2c and normalization of prolonged PEPc, while ICT shortening was less observed. In 2 patients with cor pulmonale a pulmonary oedema occurred accompanied with prolonged LVETc. During the early period of glycoside-dependent recompensation no significant correlation between STI shortening and glycoside plasma level was observed. Because of the retarded normalization of the haemodynamics of the pulmonary circulation and because of possible side-effects, rapid digitalization has to be reconsidered.

  4. Application of a novel and automated branched DNA in situ hybridization method for the rapid and sensitive localization of mRNA molecules in plant tissues1

    PubMed Central

    Bowling, Andrew J.; Pence, Heather E.; Church, Jeffrey B.

    2014-01-01

    • Premise of the study: A novel branched DNA detection technology, RNAscope in situ hybridization (ISH), originally developed for use on human clinical and animal tissues, was adapted for use in plant tissue in an attempt to overcome some of the limitations associated with traditional ISH assays. • Methods and Results: Zea mays leaf tissue was formaldehyde fixed and paraffin embedded (FFPE) and then probed with the RNAscope ISH assay for two endogenous genes, phosphoenolpyruvate carboxylase (PEPC) and phosphoenolpyruvate carboxykinase (PEPCK). Results from both manual and automated methods showed tissue- and cell-specific mRNA localization patterns expected from these well-studied genes. • Conclusions: RNAscope ISH is a sensitive method that generates high-quality, easily interpretable results from FFPE plant tissues. Automation of the RNAscope method on the Ventana Discovery Ultra platform allows significant advantages for repeatability, reduction in variability, and flexibility of workflow processes. PMID:25202621

  5. Phosphoenolpyruvate carboxykinase in cherry (Prunus avium L.) fruit during development.

    PubMed

    Walker, Robert P; Battistelli, Alberto; Moscatello, Stefano; Chen, Zhi-Hui; Leegood, Richard C; Famiani, Franco

    2011-11-01

    In this study the abundance and location of phosphoenolpyruvate carboxykinase (PEPCK) was determined in the flesh and skin of the sweet cherry (Prunus avium L.) cultivar Durone Nero II during development. PEPCK was not present in young fruit but appeared in both tissues as the fruit increased in size. In these there was no net dissimilation of malic acid, which accounts for the bulk of their organic acid contents when PEPCK was present. To assist in understanding the function of PEPCK, the abundance of a number of other enzymes was determined. These enzymes were aspartate aminotransferase (AspAT), glutamine synthetase (GS), phosphoenolpyruvate carboxylase (PEPC), pyruvate, orthophosphate dikinase (PPDK), and ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco). A potential role for PEPCK in the regulation of pH and the utilization of malate in gluconeogenesis in the flesh and skin of cherries is presented.

  6. AN UPDATE ON NIF PULSED POWER

    SciTech Connect

    Arnold, P A; James, G F; Petersen, D E; Pendleton, D L; McHale, G B; Barbosa, F; Runtal, A S; Stratton, P L

    2009-06-22

    The National Ignition Facility (NIF) is a 192-beam laser fusion driver operating at Lawrence Livermore National Laboratory. NIF relies on three large-scale pulsed power systems to achieve its goals: the Power Conditioning Unit (PCU), which provides flashlamp excitation for the laser's injection system; the Power Conditioning System (PCS), which provides the multi-megajoule pulsed excitation required to drive flashlamps in the laser's optical amplifiers; and the Plasma Electrode Pockels Cell (PEPC), which enables NIF to take advantage of a fourpass main amplifier. Years of production, installation, and commissioning of the three NIF pulsed power systems are now complete. Seven-day-per-week operation of the laser has commenced, with the three pulsed power systems providing routine support of laser operations. We present the details of the status and operational experience associated with the three systems along with a projection of the future for NIF pulsed power.

  7. Effects of different dwarfing interstocks on key enzyme activities and the expression of genes related to malic acid metabolism in Red Fuji apples.

    PubMed

    Shi, J; Li, F F; Ma, H; Li, Z Y; Xu, J Z

    2015-12-22

    In this experiment, the test materials were 'Red Fuji' apple trees grafted onto three interstocks (No. 53, No. 111, and No. 236), which were chosen from SH40 seeding interstocks. The content of malic acid, the enzyme activities, and the expression of genes related to malic acid metabolism were determined during fruit development.The results showed that malic acid content in the ripe fruit on interstock No. 53 was higher than that in the interstock No. 111 fruit. The malate dehydrogenase (NAD-MDH) activity in apples on interstock No. 53 was highest on Day 30, Day 100, and Day 160 after bloom, and the malic enzyme (NADP-ME) activity in apples on interstock No. 111 was higher than in the interstock No. 53 fruit from Day 70 to Day 100 after bloom. The relative expression of NAD-MDH genes in interstock No. 53 fruit was higher than in No. 236 fruit on Day 100 after bloom, but the relative expression of NADP-ME in No. 236 interstock fruit was lower than in No. 53 fruit. The relative expression of NAD-MDH genes in No. 53 interstock fruit was highest on Day 160 after bloom. This might have been the main reason for the difference in the accumulation of malic acid in the ripe apples.There was a positive correlation between the relative expression of phosphoenolpyruvate carboxylase (PEPC) and the malic acid content of the fruit, and the content of malic acid in the apples was affected by the PEPC activity during the early developmental stage.

  8. Plasticity of crassulacean acid metabolism at subtropical latitudes: a pineapple case study.

    PubMed

    Rainha, Nuno; Medeiros, Violante P; Câmara, Mariana; Faustino, Hélder; Leite, João P; Barreto, Maria do Carmo; Cruz, Cristina; Pacheco, Carlos A; Ponte, Duarte; Bernardes da Silva, Anabela

    2016-01-01

    Plants with the crassulacean acid metabolism (CAM) express high-metabolic plasticity, to adjust to environmental stresses. This article hypothesizes that irradiance and nocturnal temperatures are the major limitations for CAM at higher latitudes such as the Azores (37°45'N). Circadian CAM expression in Ananas comosus L. Merr. (pineapple) was assessed by the diurnal pattern of leaf carbon fixation into l-malate at the solstices and equinoxes, and confirmed by determining maximal phosphoenolpyruvate carboxylase (PEPC) activity in plant material. Metabolic adjustments to environmental conditions were confirmed by gas exchange measurements, and integrated with environmental data to determine CAM's limiting factors: light and temperature. CAM plasticity was observed at the equinoxes, under similar photoperiods, but different environmental conditions. In spring, CAM expression was similar between vegetative and flowering plants, while in autumn, flowering (before anthesis) and fructifying (with fully developed fruit before ripening) plants accumulated more l-malate. Below 100 µmol m(-2) s(-1) , CAM phase I was extended, reducing CAM phase III during the day. Carbon fixation inhibition may occur by two major pathways: nocturnal temperature (<15°C) inhibiting PEPC activity and l-malate accumulation; and low irradiance influencing the interplay between CAM phase I and III, affecting carboxylation and decarboxylation. Both have important consequences for plant development in autumn and winter. Observations were confirmed by flowering time prediction using environmental data, emphasizing that CAM expression had a strong seasonal regulation due to a complex network response to light and temperature, allowing pineapple to survive in environments not suitable for high productivity.

  9. Hydrogen sulphide improves adaptation of Zea mays seedlings to iron deficiency.

    PubMed

    Chen, Juan; Wu, Fei-Hua; Shang, Yu-Ting; Wang, Wen-Hua; Hu, Wen-Jun; Simon, Martin; Liu, Xiang; Shangguan, Zhou-Ping; Zheng, Hai-Lei

    2015-11-01

    Hydrogen sulphide (H2S) is emerging as a potential molecule involved in physiological regulation in plants. However, whether H2S regulates iron-shortage responses in plants is largely unknown. Here, the role of H2S in modulating iron availability in maize (Zea mays L. cv Canner) seedlings grown in iron-deficient culture solution is reported. The main results are as follows: Firstly, NaHS, a donor of H2S, completely prevented leaf interveinal chlorosis in maize seedlings grown in iron-deficient culture solution. Secondly, electron micrographs of mesophyll cells from iron-deficient maize seedlings revealed plastids with few photosynthetic lamellae and rudimentary grana. On the contrary, mesophyll chloroplasts appeared completely developed in H2S-treated maize seedlings. Thirdly, H2S treatment increased iron accumulation in maize seedlings by changing the expression levels of iron homeostasis- and sulphur metabolism-related genes. Fourthly, phytosiderophore (PS) accumulation and secretion were enhanced by H2S treatment in seedlings grown in iron-deficient solution. Indeed, the gene expression of ferric-phytosiderophore transporter (ZmYS1) was specifically induced by iron deficiency in maize leaves and roots, whereas their abundance was decreased by NaHS treatment. Lastly, H2S significantly enhanced photosynthesis through promoting the protein expression of ribulose-1,5-bisphosphate carboxylase large subunit (RuBISCO LSU) and phosphoenolpyruvate carboxylase (PEPC) and the expression of genes encoding RuBISCO large subunit (RBCL), small subunit (RBCS), D1 protein (psbA), and PEPC in maize seedlings grown in iron-deficient solution. These results indicate that H2S is closely related to iron uptake, transport, and accumulation, and consequently increases chlorophyll biosynthesis, chloroplast development, and photosynthesis in plants.

  10. Leaf anatomical traits which accommodate the facultative engagement of crassulacean acid metabolism in tropical trees of the genus Clusia.

    PubMed

    Barrera Zambrano, V Andrea; Lawson, Tracy; Olmos, Enrique; Fernández-García, Nieves; Borland, Anne M

    2014-07-01

    Succulence and leaf thickness are important anatomical traits in CAM plants, resulting from the presence of large vacuoles to store organic acids accumulated overnight. A higher degree of succulence can result in a reduction in intercellular air space which constrains internal conductance to CO2. Thus, succulence presents a trade-off between the optimal anatomy for CAM and the internal structure ideal for direct C3 photosynthesis. This study examined how plasticity for the reversible engagement of CAM in the genus Clusia could be accommodated by leaf anatomical traits that could facilitate high nocturnal PEPC activity without compromising the direct day-time uptake of CO2 via Rubisco. Nine species of Clusia ranging from constitutive C3 through C3/CAM intermediates to constitutive CAM were compared in terms of leaf gas exchange, succulence, specific leaf area, and a range of leaf anatomical traits (% intercellular air space (IAS), length of mesophyll surface exposed to IAS per unit area, cell size, stomatal density/size). Relative abundances of PEPC and Rubisco proteins in different leaf tissues of a C3 and a CAM-performing species of Clusia were determined using immunogold labelling. The results indicate that the relatively well-aerated spongy mesophyll of Clusia helps to optimize direct C3-mediated CO2 fixation, whilst enlarged palisade cells accommodate the potential for C4 carboxylation and nocturnal storage of organic acids. The findings provide insight on the optimal leaf anatomy that could accommodate the bioengineering of inducible CAM into C3 crops as a means of improving water use efficiency without incurring detrimental consequences for direct C3-mediated photosynthesis.

  11. Rubisco and PEP carboxylase responses to changing irradiance in a Brazilian Cerrado tree species, Qualea grandiflora Mart. (Vochysiaceae).

    PubMed

    Paulilo, M T; Besford, R T; Wilkins, D

    1994-02-01

    The activities of ribulose-1,5-bisphosphate carboxylase-oxygenase, Rubisco (E.C. 4.1.1.39) and phosphoenolpyruvate carboxylase, PEPc (E.C. 4.1.1.31), and concentrations of protein and chlorophyll were measured in extracts from cotyledons and first leaves of Qualea grandiflora Mart. (Vochysiaceae) seedlings after transfer from high-light (20 days at 320 micro mol m(-2) s(-1), PAR) to low-light (35 days at 120 micro mol m(-2) s(-1), PAR) conditions. When Tween 20 and glycerol were added to the extraction medium, Rubisco activities obtained for Qualea grandiflora were comparable to published values for several coniferous species and the broad-leaved species, Prunus avium L. Stella, grown in a similar light environment. Rubisco activity in cotyledons of Q. grandiflora grown in high light for 20 days and then transferred to low light for a further 35 days was similar to the activity in cotyledons of plants grown continuously in high light. However, the first leaf above the cotyledons showed a greater response to the change in irradiance; in high light, Rubisco activity of the first leaf was 1.8 times higher on a fresh weight basis and 2.7 times higher on an area basis than that of leaves transferred from high to low light. Fresh weight and chlorophyll concentration expressed on a unit leaf area basis were also higher in the high-light treatment. These responses to irradiance are indicative of a species adapted to growth in an unshaded habitat. The PEPc activity in leaves was 15% of Rubisco activity, which is typical of species with a C(3) photosynthetic pathway. The relatively slow growth rate of Q. grandiflora observed in these experiments could not be attributed to a low carboxylation capacity per unit leaf area.

  12. CO2-concentrating mechanisms in Egeria densa, a submersed aquatic plant.

    PubMed

    Lara, María V; Casati, Paula; Andreo, Carlos S

    2002-08-01

    Egeria densa is an aquatic higher plant which has developed different mechanisms to deal with photosynthesis under conditions of low CO2 availability. On the one hand it shows leaf pH-polarity, which has been proposed to be used for bicarbonate utilization. In this way, at high light intensities and low dissolved carbon concentration, this species generates a low pH at the adaxial leaf surface. This acidification shifts the equilibrium HCO3-/CO2 towards CO2, which enters the cell by passive diffusion. By this means, E. densa increases the concentration of CO2 available for photosynthesis inside the cells, when this gas is limiting. On the other hand, under stress conditions resulting from high temperature and high light intensities, it shows a biochemical adaptation with the induction of a C4-like mechanism but without Kranz anatomy. Transfer from low to high temperature and light conditions induces increased levels of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) and NADP-malic enzyme (NADP-ME, EC 1.1.1.40), both key enzymes participating in the Hatch-Slack cycle in plants with C4 metabolism. Moreover, one PEPC isoform, whose synthesis is induced by high temperature and light, is phosphorylated in the light, and changes in kinetic and regulatory properties are correlated with changes in the phosphorylation state of this enzyme. In the present review, we describe these two processes in this submersed angiosperm that appear to help it perform photosynthesis under conditions of extreme temperatures and high light intensities.

  13. Spatial division of phosphoenolpyruvate carboxylase and nitrate reductase activity and its regulation by cytokinins in CAM-induced leaves of Guzmania monostachia (Bromeliaceae).

    PubMed

    Pereira, Paula Natália; Purgatto, Eduardo; Mercier, Helenice

    2013-08-15

    Crassulacean acid metabolism (CAM) is a physiological adaptation of plants that live in stress environment conditions. A good model of CAM modulation is the epiphytic bromeliad, Guzmania monostachia, which switches between two photosynthetic pathways (C3-CAM) in response to different environmental conditions, such as light stress and water availability. Along the leaf length a gradient of acidity can be observed when G. monostachia plants are kept under water deficiency. Previous studies showed that the apical portions of the leaves present higher expression of CAM, while the basal regions exhibit lower expression of this photosynthetic pathway. The present study has demonstrated that it is possible to induce the CAM pathway in detached leaves of G. monostachia kept under water deficit for 7 d. Also, it was evaluated whether CAM expression can be modulated in detached leaves of Guzmania and whether some spatial separation between NO3(-) reduction and CO2 fixation occurs in basal and apical portions of the leaf. In addition, we analyzed the involvement of endogenous cytokinins (free and ribosylated forms) as possible signal modulating both NO3(-) reduction and CO2 fixation along the leaf blade of this bromeliad. Besides demonstrating a clear spatial and functional separation of carbon and nitrogen metabolism along G. monostachia leaves, the results obtained also indicated a probable negative correlation between endogenous free cytokinins - zeatin (Z) and isopentenyladenine (iP) - concentration and PEPC activity in the apical portions of G. monostachia leaves kept under water deficit. On the other hand, a possible positive correlation between endogenous Z and iP levels and NR activity in basal portions of drought-exposed and control leaves was verified. Together with the observations presented above, results obtained with exogenous cytokinins treatments, strongly suggest that free cytokinins might act as a stimulatory signal involved in NR activity regulation and as

  14. Pulse power requirements for large aperture optical switches based on plasma electrode Pockels cells

    SciTech Connect

    Rhodes, M.A.; Taylor, J.

    1992-06-01

    We discuss very large-aperture optical switches (greater than 30 [times] 30 cm) as an enabling technology for inertial confinement fusion drivers based on multipass laser amplifiers. Large-scale laser fusion drivers such as the Nova laser have been based on single-pass amplifier designs in part because of the unavailability of a suitable large-aperture switch. We are developing an optical switch based on a Pockels cell employing plasma-electrodes. A plasma-electrode Pockels cell (PEPC) is a longitudinal-mode Pockels cell in which a plasma discharge is formed on each side of an electro-optic crystal (typically KDP or deuterated KDP, often designated KD*P). The plasmas formed on either side of the crystal act as transparent electrodes for a switching-pulse and are intended to allow uniform charging of the entire crystal. The switching-pulse is a nominally rectangular high-voltage pulse equal to the half-wave voltage V[sub x] ( 8 kV for KD*P or 17 kV for KDP) and is applied across the crystal via the plasma-electrodes. When the crystal is charged to V[sub x], the polarization of an incoming, linearly polarized, laser beam is rotated by 90[degree]. When used in conjunction with an appropriate, passive polarizer, an optical switch is thus realized. A switch with a clear aperture of 37 [times] 37 cm is now in construction for the Beamlet laser which will serve as a test bed for this switch as well as other technologies required for an advanced NOVA laser design. In this paper, we discuss the unique power electronics requirements of PEPC optical switches.

  15. Pulse power requirements for large aperture optical switches based on plasma electrode Pockels cells

    SciTech Connect

    Rhodes, M.A.; Taylor, J.

    1992-06-01

    We discuss very large-aperture optical switches (greater than 30 {times} 30 cm) as an enabling technology for inertial confinement fusion drivers based on multipass laser amplifiers. Large-scale laser fusion drivers such as the Nova laser have been based on single-pass amplifier designs in part because of the unavailability of a suitable large-aperture switch. We are developing an optical switch based on a Pockels cell employing plasma-electrodes. A plasma-electrode Pockels cell (PEPC) is a longitudinal-mode Pockels cell in which a plasma discharge is formed on each side of an electro-optic crystal (typically KDP or deuterated KDP, often designated KD*P). The plasmas formed on either side of the crystal act as transparent electrodes for a switching-pulse and are intended to allow uniform charging of the entire crystal. The switching-pulse is a nominally rectangular high-voltage pulse equal to the half-wave voltage V{sub x} ( 8 kV for KD*P or 17 kV for KDP) and is applied across the crystal via the plasma-electrodes. When the crystal is charged to V{sub x}, the polarization of an incoming, linearly polarized, laser beam is rotated by 90{degree}. When used in conjunction with an appropriate, passive polarizer, an optical switch is thus realized. A switch with a clear aperture of 37 {times} 37 cm is now in construction for the Beamlet laser which will serve as a test bed for this switch as well as other technologies required for an advanced NOVA laser design. In this paper, we discuss the unique power electronics requirements of PEPC optical switches.

  16. Metabolic responses to iron deficiency in roots of Carrizo citrange [Citrus sinensis (L.) Osbeck. x Poncirus trifoliata (L.) Raf].

    PubMed

    Martínez-Cuenca, Mary-Rus; Iglesias, Domingo J; Talón, Manuel; Abadía, Javier; López-Millán, Ana-Flor; Primo-Millo, Eduardo; Legaz, Francisco

    2013-03-01

    The effects of iron (Fe) deficiency on the low-molecular-weight organic acid (LMWOA) metabolism have been investigated in Carrizo citrange (CC) [Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf.] roots. Major LMWOAs found in roots, xylem sap and root exudates were citrate and malate and their concentrations increased with Fe deficiency. The activities of several enzymes involved in the LMWOA metabolism were also assessed in roots. In the cytosolic fraction, the activities of malate dehydrogenase (cMDH) and phosphoenolpyruvate carboxylase (PEPC) enzymes were 132 and 100% higher in Fe-deficient conditions, whereas the activity of pyruvate kinase was 31% lower and the activity of malic enzyme (ME) did not change. In the mitochondrial fraction, the activities of fumarase, MDH and citrate synthase enzymes were 158, 117 and 53% higher, respectively, in Fe-deficient extracts when compared with Fe-sufficient controls, whereas no significant differences between treatments were found for aconitase (ACO) activity. The expression of their corresponding genes in roots of Fe-deficient plants was higher than that measured in Fe-sufficient controls, except for ACO and ME. Also, dicarboxylate-tricarboxylate carrier (DTC) expression was significantly increased in Fe-deficient roots. In conclusion, Fe deficiency in CC seedlings causes a reprogramming of the carbon metabolism that involves an increase of anaplerotic fixation of carbon via PEPC and MDH activities in the cytosol and a shift of the Krebs cycle in the mitochondria towards a non-cyclic mode, as previously described in herbaceous species. In this scheme, DTC could play an important role shuttling both malate and reducing equivalents between the cytosol and the mitochondria. As a result of this metabolic switch malate and citrate concentrations in roots, xylem sap and root exudates increase.

  17. Conserved and Divergent Rhythms of Crassulacean Acid Metabolism-Related and Core Clock Gene Expression in the Cactus Opuntia ficus-indica1[C][W

    PubMed Central

    Mallona, Izaskun; Egea-Cortines, Marcos; Weiss, Julia

    2011-01-01

    The cactus Opuntia ficus-indica is a constitutive Crassulacean acid metabolism (CAM) species. Current knowledge of CAM metabolism suggests that the enzyme phosphoenolpyruvate carboxylase kinase (PPCK) is circadian regulated at the transcriptional level, whereas phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), NADP-malic enzyme (NADP-ME), and pyruvate phosphate dikinase (PPDK) are posttranslationally controlled. As little transcriptomic data are available from obligate CAM plants, we created an expressed sequence tag database derived from different organs and developmental stages. Sequences were assembled, compared with sequences in the National Center for Biotechnology Information nonredundant database for identification of putative orthologs, and mapped using Kyoto Encyclopedia of Genes and Genomes Orthology and Gene Ontology. We identified genes involved in circadian regulation and CAM metabolism for transcriptomic analysis in plants grown in long days. We identified stable reference genes for quantitative polymerase chain reaction and found that OfiSAND, like its counterpart in Arabidopsis (Arabidopsis thaliana), and OfiTUB are generally appropriate standards for use in the quantification of gene expression in O. ficus-indica. Three kinds of expression profiles were found: transcripts of OfiPPCK oscillated with a 24-h periodicity; transcripts of the light-active OfiNADP-ME and OfiPPDK genes adapted to 12-h cycles, while transcript accumulation patterns of OfiPEPC and OfiMDH were arrhythmic. Expression of the circadian clock gene OfiTOC1, similar to Arabidopsis, oscillated with a 24-h periodicity, peaking at night. Expression of OfiCCA1 and OfiPRR9, unlike in Arabidopsis, adapted best to a 12-h rhythm, suggesting that circadian clock gene interactions differ from those of Arabidopsis. Our results indicate that the evolution of CAM metabolism could be the result of modified circadian regulation at both the transcriptional and posttranscriptional

  18. Conserved and divergent rhythms of crassulacean acid metabolism-related and core clock gene expression in the cactus Opuntia ficus-indica.

    PubMed

    Mallona, Izaskun; Egea-Cortines, Marcos; Weiss, Julia

    2011-08-01

    The cactus Opuntia ficus-indica is a constitutive Crassulacean acid metabolism (CAM) species. Current knowledge of CAM metabolism suggests that the enzyme phosphoenolpyruvate carboxylase kinase (PPCK) is circadian regulated at the transcriptional level, whereas phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), NADP-malic enzyme (NADP-ME), and pyruvate phosphate dikinase (PPDK) are posttranslationally controlled. As little transcriptomic data are available from obligate CAM plants, we created an expressed sequence tag database derived from different organs and developmental stages. Sequences were assembled, compared with sequences in the National Center for Biotechnology Information nonredundant database for identification of putative orthologs, and mapped using Kyoto Encyclopedia of Genes and Genomes Orthology and Gene Ontology. We identified genes involved in circadian regulation and CAM metabolism for transcriptomic analysis in plants grown in long days. We identified stable reference genes for quantitative polymerase chain reaction and found that OfiSAND, like its counterpart in Arabidopsis (Arabidopsis thaliana), and OfiTUB are generally appropriate standards for use in the quantification of gene expression in O. ficus-indica. Three kinds of expression profiles were found: transcripts of OfiPPCK oscillated with a 24-h periodicity; transcripts of the light-active OfiNADP-ME and OfiPPDK genes adapted to 12-h cycles, while transcript accumulation patterns of OfiPEPC and OfiMDH were arrhythmic. Expression of the circadian clock gene OfiTOC1, similar to Arabidopsis, oscillated with a 24-h periodicity, peaking at night. Expression of OfiCCA1 and OfiPRR9, unlike in Arabidopsis, adapted best to a 12-h rhythm, suggesting that circadian clock gene interactions differ from those of Arabidopsis. Our results indicate that the evolution of CAM metabolism could be the result of modified circadian regulation at both the transcriptional and posttranscriptional

  19. Low Temperature Induced Changes in Citrate Metabolism in Ponkan (Citrus reticulata Blanco cv. Ponkan) Fruit during Maturation

    PubMed Central

    Lin, Qiong; Qian, Jing; Zhao, Chenning; Wang, Dengliang; Liu, Chunrong; Wang, Zhidong; Sun, Chongde; Chen, Kunsong

    2016-01-01

    Citrate is the most important organic acid in citrus fruit, and its concentration in fruit cells is regulated mainly by the balance between synthesis and degradation. Ponkan (Citrus reticulate Blanco cv. Ponkan) is one of the major citrus cultivars grew in China, and the fruit are picked before fully mature to avoid bad weather. Greenhouse production is widely used to prolong the maturation period and improve the quality of Ponkan fruit by maintaining adequate temperature and providing protection from adverse weather. In this research, Ponkan fruit cultivated in either a greenhouse or open field were used to investigate differences in the expression of genes related to citrate metabolism during maturation in the two environments. The citrate contents were higher in open field fruit, and were mainly correlated with expressions of CitPEPCs, CitCSs, CitAco3 and CitGAD4, which were significantly increased. In addition, the impacts of low temperature (LT) and water stress (WS) on citrate metabolism in Ponkan were investigated during fruit maturation. The citrate contents in LT fruit were significantly increased, by between 1.4–1.9 fold, compared to the control; it showed no significant difference in fruit with water stress treatment compared to the control fruit. Furthermore, the expressions of CitPEPCs, CitCSs, CitAco3 and CitGAD4 were significantly increased in response to LT treatment, but showed no significant difference in WS compared to the control fruit. Thus, it can be concluded that low temperature may be the main factor influencing citrate metabolism during maturation in Ponkan fruit. PMID:27249065

  20. A field-grown transgenic tomato line expressing higher levels of polyamines reveals legume cover crop mulch-specific perturbations in fruit phenotype at the levels of metabolite profiles, gene expression, and agronomic characteristics.

    PubMed

    Neelam, Anil; Cassol, Tatiana; Mehta, Roshni A; Abdul-Baki, Aref A; Sobolev, Anatoli P; Goyal, Ravinder K; Abbott, Judith; Segre, Anna L; Handa, Avtar K; Mattoo, Autar K

    2008-01-01

    Genetic modification of crop plants to introduce desirable traits such as nutritional enhancement, disease and pest resistance, and enhanced crop productivity is increasingly seen as a promising technology for sustainable agriculture and boosting food production in the world. Independently, cultural practices that utilize alternative agriculture strategies including organic cultivation subscribe to sustainable agriculture by limiting chemical usage and reduced tillage. How the two together affect fruit metabolism or plant growth in the field or whether they are compatible has not yet been tested. Fruit-specific yeast S-adenosylmethionine decarboxylase (ySAMdc) line 579HO, and a control line 556AZ were grown in leguminous hairy vetch (Vicia villosa Roth) (HV) mulch and conventional black polyethylene (BP) mulch, and their fruit analysed. Significant genotypexmulch-dependent interactions on fruit phenotype were exemplified by differential profiles of 20 fruit metabolites such as amino acids, sugars, and organic acids. Expression patterns of the ySAMdc transgene, and tomato SAMdc, E8, PEPC, and ICDHc genes were compared between the two lines as a function of growth on either BP or HV mulch. HV mulch significantly stimulated the accumulation of asparagine, glutamate, glutamine, choline, and citrate concomitant with a decrease in glucose in the 556AZ fruits during ripening as compared to BP. It enables a metabolic system in tomato somewhat akin to the one in higher polyamine-accumulating transgenic fruit that have higher phytonutrient content. Finally, synergism was found between HV mulch and transgenic tomato in up-regulating N:C indicator genes PEPC and ICDHc in the fruit.

  1. Influence of light and nitrogen on the photosynthetic efficiency in the C4 plant Miscanthus × giganteus.

    PubMed

    Ma, Jian-Ying; Sun, Wei; Koteyeva, Nuria K; Voznesenskaya, Elena; Stutz, Samantha S; Gandin, Anthony; Smith-Moritz, Andreia M; Heazlewood, Joshua L; Cousins, Asaph B

    2017-01-01

    There are numerous studies describing how growth conditions influence the efficiency of C4 photosynthesis. However, it remains unclear how changes in the biochemical capacity versus leaf anatomy drives this acclimation. Therefore, the aim of this study was to determine how growth light and nitrogen availability influence leaf anatomy, biochemistry and the efficiency of the CO2 concentrating mechanism in Miscanthus × giganteus. There was an increase in the mesophyll cell wall surface area but not cell well thickness in the high-light (HL) compared to the low-light (LL) grown plants suggesting a higher mesophyll conductance in the HL plants, which also had greater photosynthetic capacity. Additionally, the HL plants had greater surface area and thickness of bundle-sheath cell walls compared to LL plants, suggesting limited differences in bundle-sheath CO2 conductance because the increased area was offset by thicker cell walls. The gas exchange estimates of phosphoenolpyruvate carboxylase (PEPc) activity were significantly less than the in vitro PEPc activity, suggesting limited substrate availability in the leaf due to low mesophyll CO2 conductance. Finally, leakiness was similar across all growth conditions and generally did not change under the different measurement light conditions. However, differences in the stable isotope composition of leaf material did not correlate with leakiness indicating that dry matter isotope measurements are not a good proxy for leakiness. Taken together, these data suggest that the CO2 concentrating mechanism in Miscanthus is robust under low-light and limited nitrogen growth conditions, and that the observed changes in leaf anatomy and biochemistry likely help to maintain this efficiency.

  2. Development of structural and biochemical characteristics of C(4) photosynthesis in two types of Kranz anatomy in genus Suaeda (family Chenopodiaceae).

    PubMed

    Koteyeva, Nuria K; Voznesenskaya, Elena V; Berry, James O; Chuong, Simon D X; Franceschi, Vincent R; Edwards, Gerald E

    2011-05-01

    Genus Suaeda (family Chenopodiaceae, subfamily Suaedoideae) has two structural types of Kranz anatomy consisting of a single compound Kranz unit enclosing vascular tissue. One, represented by Suaeda taxifolia, has mesophyll (M) and bundle sheath (BS) cells distributed around the leaf periphery. The second, represented by Suaeda eltonica, has M and BS surrounding vascular bundles in the central plane. In both, structural and biochemical development of C(4) occurs basipetally, as observed by analysis of the maturation gradient on longitudinal leaf sections. This progression in development was also observed in mid-sections of young, intermediate, and mature leaves in both species, with three clear stages: (i) monomorphic chloroplasts in the two cell types in younger tissue with immunolocalization and in situ hybridization showing ribulose bisphosphate carboxylase oxygenase (Rubisco) preferentially localized in BS chloroplasts, and increasing in parallel with the establishment of Kranz anatomy; (ii) vacuolization and selective organelle positioning in BS cells, with occurrence of phosphoenolpyruvate carboxylase (PEPC) and immunolocalization showing that it is preferentially in M cells; (iii) establishment of chloroplast dimorphism and mitochondrial differentiation in mature tissue and full expression of C(4) biochemistry including pyruvate, Pi dikinase (PPDK) and NAD-malic enzyme (NAD-ME). Accumulation of rbcL mRNA preceded its peptide expression, occurring prior to organelle positioning and differentiation. During development there was sequential expression and increase in levels of Rubisco and PEPC followed by NAD-ME and PPDK, and an increase in the (13)C/(12)C isotope composition of leaves to values characteristic of C(4) photosynthesis. The findings indicate that these two forms of NAD-ME type C(4) photosynthesis evolved in parallel within the subfamily with similar ontogenetic programmes.

  3. Outer Surface Protein C Peptide Derived from Borrelia burgdorferi Sensu Stricto as a Target for Serodiagnosis of Early Lyme Disease

    PubMed Central

    Arnaboldi, Paul M.; Seedarnee, Rudra; Sambir, Mariya; Callister, Steven M.; Imparato, Josephine A.

    2013-01-01

    Current serodiagnostic assays for Lyme disease are inadequate at detecting early infection due to poor sensitivity and nonspecificity that arise from the use of whole bacteria or bacterial proteins as assay targets; both targets contain epitopes that are cross-reactive with epitopes found in antigens of other bacterial species. Tests utilizing peptides that contain individual epitopes highly specific for Borrelia burgdorferi as diagnostic targets are an attractive alternative to current assays. Using an overlapping peptide library, we mapped linear epitopes in OspC, a critical virulence factor of B. burgdorferi required for mammalian infection, and confirmed the results by enzyme-linked immunosorbent assay (ELISA). We identified a highly conserved 20-amino-acid peptide epitope, OspC1. Via ELISA, OspC1 detected specific IgM and/or IgG in 60 of 98 serum samples (62.1%) obtained from patients with erythema migrans (early Lyme disease) at the time of their initial presentation. By comparison, the commercially available OspC peptide PepC10 detected antibody in only 48 of 98 serum samples (49.0%). In addition, OspC1 generated fewer false-positive results among negative healthy and diseased (rheumatoid arthritis and positive Rapid Plasma Reagin [RPR+] test result) control populations than did PepC10. Both highly specific and more sensitive than currently available OspC peptides, OspC1 could have value as a component of a multipeptide Lyme disease serological assay with significantly improved capabilities for the diagnosis of early infection. PMID:23365204

  4. Hydrogen sulphide improves adaptation of Zea mays seedlings to iron deficiency

    PubMed Central

    Chen, Juan; Wu, Fei-Hua; Shang, Yu-Ting; Wang, Wen-Hua; Hu, Wen-Jun; Simon, Martin; Liu, Xiang; Shangguan, Zhou-Ping; Zheng, Hai-Lei

    2015-01-01

    Hydrogen sulphide (H2S) is emerging as a potential molecule involved in physiological regulation in plants. However, whether H2S regulates iron-shortage responses in plants is largely unknown. Here, the role of H2S in modulating iron availability in maize (Zea mays L. cv Canner) seedlings grown in iron-deficient culture solution is reported. The main results are as follows: Firstly, NaHS, a donor of H2S, completely prevented leaf interveinal chlorosis in maize seedlings grown in iron-deficient culture solution. Secondly, electron micrographs of mesophyll cells from iron-deficient maize seedlings revealed plastids with few photosynthetic lamellae and rudimentary grana. On the contrary, mesophyll chloroplasts appeared completely developed in H2S-treated maize seedlings. Thirdly, H2S treatment increased iron accumulation in maize seedlings by changing the expression levels of iron homeostasis- and sulphur metabolism-related genes. Fourthly, phytosiderophore (PS) accumulation and secretion were enhanced by H2S treatment in seedlings grown in iron-deficient solution. Indeed, the gene expression of ferric-phytosiderophore transporter (ZmYS1) was specifically induced by iron deficiency in maize leaves and roots, whereas their abundance was decreased by NaHS treatment. Lastly, H2S significantly enhanced photosynthesis through promoting the protein expression of ribulose-1,5-bisphosphate carboxylase large subunit (RuBISCO LSU) and phosphoenolpyruvate carboxylase (PEPC) and the expression of genes encoding RuBISCO large subunit (RBCL), small subunit (RBCS), D1 protein (psbA), and PEPC in maize seedlings grown in iron-deficient solution. These results indicate that H2S is closely related to iron uptake, transport, and accumulation, and consequently increases chlorophyll biosynthesis, chloroplast development, and photosynthesis in plants. PMID:26208645

  5. Metabolism of the seed and endocarp of cherry (Prunus avium L.) during development.

    PubMed

    Walker, Robert P; Battistelli, Alberto; Moscatello, Stefano; Chen, Zhi-Hui; Leegood, Richard C; Famiani, Franco

    2011-08-01

    In this study some aspects of organic and amino acid metabolism in cherry endocarp and seed were investigated during their development. The abundance and location of a number of enzymes involved in these processes were investigated. These enzymes were aspartate aminotransferase (AspAT; EC:2.6.1.1), glutamine synthetase (GS; EC:6.3.1.2), phosphoenolpyruvate carboxylase (PEPC; EC:4.1.1.31), phosphoenolpyruvate carboxykinase (PEPCK; EC:4.1.1.49), and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC:4.1.1.39). There was a transient and massive accumulation of vegetative storage proteins in the endocarp. These proteins were remobilised as the endocarp lignified and at the same time that proteins were accumulated in the seed. This raised the possibility that a proportion of imported amino acids were temporarily stored in the endocarp as protein, and that these were later utilised by the seed when it started to accumulate storage proteins. Rubisco was present in the embryo and integuments of the seed although no chlorophyll was present. This is the first time that Rubisco has been detected in non-green seeds. The maximum abundance of Rubisco in the seed coincided with the deposition of seed storage proteins. A possible function for Rubisco in cherry seed is discussed. PEPCK was located in the integuments and appeared when seed storage proteins were being accumulated. In the integuments and embryo AspAT, GS, PEPC and Rubisco also appeared, or greatly increased in abundance, when seed storage proteins were being deposited.

  6. 24 CFR 3280.715 - Circulating air systems.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Circulating air systems. 3280.715... Systems § 3280.715 Circulating air systems. (a) Supply system. (1) Supply ducts and any dampers contained..., Class 1, or Class 2 air ducts. Class 2 air ducts shall be located at least 3 feet from the...

  7. 49 CFR 192.903 - What definitions apply to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or (iv) Any area in a Class 1 or Class 2 location where the potential...

  8. 37 CFR 2.86 - Application may include multiple classes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... multiple classes. 2.86 Section 2.86 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Classification § 2.86 Application may... or services in each class; (2) Submit an application filing fee for each class, as set forth in §...

  9. Nonbright spot AVO: Two examples

    SciTech Connect

    Ross, C.P.; Kinman, D.L.

    1994-12-31

    Utilization of amplitude-versus-offset (AVO) attribute sections such as the product of the normal incidence trace and gradient trace have been used extensively in bright spot (Class 3) AVO analysis and interpretation. However, while these sections have often worked well with Class 3 responses they are not reliable indicators of non-bright spot (Class 2) seismic anomalies. Analyzing Class 2 seismic data with AVO products will: (1) not detect the gas-charged reservoir because of near-zero acoustic impedance contrast between the sands and encasing shales, or (2) yield an incorrect (negative) AVO product if the normal incidence and gradient values are opposite in sign. Class 2 offset responses are divided into two sub-categories: those with phase reversals (Class 2p) and those without phase reversals (Class 2). An AVO procedure for these types of Class 2 anomalies is presented through two examples. The technique better exploits the nature of the prestack response, yielding a more definitive AVO attribute section, and the technique is adaptive to both Class 2 and Class 2p responses. When compared to a conventionally processed relative amplitude seismic section with characteristically low amplitude responses for near-zero acoustic impedance sands, this procedure clearly denotes the presence of gas-charged pore fluids within the reservoir.

  10. 49 CFR 174.204 - Tank car delivery of gases, including cryogenic liquids.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Tank car delivery of gases, including cryogenic... CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.204 Tank car delivery of gases, including cryogenic liquids. (a) A tank car containing Class 2 (gases) material may not be unloaded...

  11. 49 CFR 192.903 - What definitions apply to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or (iv) Any area in a Class 1 or Class 2 location where the potential...

  12. 49 CFR 192.903 - What definitions apply to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ....5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or (iv) Any area in a Class 1 or Class 2 location where the potential...

  13. 14 CFR 101.29 - Information requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.29 Information requirements. (a) Class 2—High-Power Rockets. When a Class 2—High-Power Rocket requires a certificate of waiver or authorization, the person planning the...

  14. 14 CFR 101.29 - Information requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.29 Information requirements. (a) Class 2—High-Power Rockets. When a Class 2—High-Power Rocket requires a certificate of waiver or authorization, the person planning the...

  15. 14 CFR 101.29 - Information requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... BALLOONS Amateur Rockets § 101.29 Information requirements. (a) Class 2—High-Power Rockets. When a Class 2—High-Power Rocket requires a certificate of waiver or authorization, the person planning the operation.... (b) Class 3—Advanced High-Power Rockets. When a Class 3—Advanced High-Power Rocket requires...

  16. 14 CFR 101.29 - Information requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... BALLOONS Amateur Rockets § 101.29 Information requirements. (a) Class 2—High-Power Rockets. When a Class 2—High-Power Rocket requires a certificate of waiver or authorization, the person planning the operation.... (b) Class 3—Advanced High-Power Rockets. When a Class 3—Advanced High-Power Rocket requires...

  17. 49 CFR 174.204 - Tank car delivery of gases, including cryogenic liquids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tank car delivery of gases, including cryogenic... CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.204 Tank car delivery of gases, including cryogenic liquids. (a) A tank car containing Class 2 (gases) material may not be unloaded...

  18. 49 CFR 174.204 - Tank car delivery of gases, including cryogenic liquids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Tank car delivery of gases, including cryogenic... CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.204 Tank car delivery of gases, including cryogenic liquids. (a) A tank car containing Class 2 (gases) material may not be unloaded...

  19. 49 CFR 174.204 - Tank car delivery of gases, including cryogenic liquids.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Tank car delivery of gases, including cryogenic... CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.204 Tank car delivery of gases, including cryogenic liquids. (a) A tank car containing Class 2 (gases) material may not be unloaded...

  20. 49 CFR 174.204 - Tank car delivery of gases, including cryogenic liquids.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Tank car delivery of gases, including cryogenic... CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases) Materials § 174.204 Tank car delivery of gases, including cryogenic liquids. (a) A tank car containing Class 2 (gases) material may not be unloaded...

  1. 49 CFR 192.903 - What definitions apply to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or (iv) Any area in a Class 1 or Class 2 location where the potential...

  2. 24 CFR 3280.715 - Circulating air systems.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... steel, tin-plated steel, or aluminum, or shall be listed Class 0, Class 1, or Class 2 air ducts. Class 2... with the structure shall be of durable construction that can be demonstrated to be equally resistant to fire and deterioration. Ducts constructed from sheet metal shall be in accordance with the...

  3. Stem juice production of the C4 sugarcane (Saccharum officinarum) is enhanced by growth at double-ambient CO2 and high temperature.

    PubMed

    Vu, Joseph C V; Allen, Leon H

    2009-07-15

    Two cultivars of sugarcane (Saccharum officinarum cv. CP73-1547 and CP88-1508) were grown for 3 months in paired-companion, temperature-gradient, sunlit greenhouses under daytime [CO2] of 360 (ambient) and 720 (double ambient) micromol mol(-1) and at temperatures of 1.5 degrees C (near ambient) and 6.0 degrees C higher than outside ambient temperature. Leaf area and biomass, stem biomass and juice and CO2 exchange rate (CER) and activities of ribulose bisphosphate carboxylase-oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC) of fully developed leaves were measured at harvest. On a main stem basis, leaf area, leaf dry weight, stem dry weight and stem juice volume were increased by growth at doubled [CO2] or high temperature. Such increases were even greater under combination of doubled [CO2]/high temperature. Plants grown at doubled [CO2]/high temperature combination averaged 50%, 26%, 84% and 124% greater in leaf area, leaf dry weight, stem dry weight and stem juice volume, respectively, compared with plants grown at ambient [CO2]/near-ambient temperature combination. In addition, plants grown at doubled [CO2]/high temperature combination were 2-3-fold higher in stem soluble solids than those at ambient [CO2]/near-ambient temperature combination. Although midday CER of fully developed leaves was not affected by doubled [CO2] or high temperature, plants grown at doubled [CO2] were 41-43% less in leaf stomatal conductance and 69-79% greater in leaf water-use efficiency, compared with plants grown at ambient [CO2]. Activity of PEPC was down-regulated 23-32% at doubled [CO2], while high temperature did not have a significant impact on this enzyme. Activity of Rubisco was not affected by growth at doubled [CO2], but was reduced 15-28% at high temperature. The increases in stem juice production and stem juice soluble solids concentration for sugarcane grown at doubled [CO2] or high temperature, or at doubled [CO2]/high temperature combination, were partially

  4. Breeding response of transcript profiling in developing seeds of Brassica napus

    PubMed Central

    Hu, Yaping; Wu, Gang; Cao, Yinglong; Wu, Yuhua; Xiao, Ling; Li, Xiaodan; Lu, Changming

    2009-01-01

    Background The upgrading of rapeseed cultivars has resulted in a substantial improvement in yield and quality in China over the past 30 years. With the selective pressure against fatty acid composition and oil content, high erucic acid- and low oil-content cultivars have been replaced by low erucic acid- and high oil-content cultivars. The high erucic acid cultivar Zhongyou 821 and its descendent, low erucic acid cultivar Zhongshuang 9, are representatives of two generations of the most outstanding Chinese rapeseed cultivars (B. napus) developed the past 2 decades. This paper compares the transcriptional profiles of Zhongshuang 9 and Zhongyou 821 for 32 genes that are principally involved in lipid biosynthesis during seed development in order to elucidate how the transcriptional profiles of these genes responded to quality improvement over the past 20 years. Results Comparison of the cultivar Zhongyou 821 with its descendent, Zhongshuang 9, shows that the transcriptional levels of seven of the 32 genes were upregulated by 30% to 109%, including FAD3, ACCase, FAE1, GKTP, Caleosin, GAPDH, and PEPC. Of the 32 genes, 10 (KAS3, β-CT, BcRK6, P450, FatA, Oleosin, FAD6, FatB, α-CT and SUC1) were downregulated by at least 20% and most by 50%. The Napin gene alone accounted for over 75% of total transcription from all 32 genes assessed in both cultivars. Most of the genes showed significant correlation with fatty acid accumulation, but the correlation in ZS9 was significantly different from that in ZY821. Higher KCR2 activity is associated with higher C16:0, C18:0, and C18:2 in both cultivars, lower C22:1 and total fatty acid content in ZY821, and lower 18:1 in ZS9. Conclusion This paper illustrates the response of the transcription levels of 32 genes to breeding in developing rapeseed seeds. Both cultivars showed similar transcription profiles, with the Napin gene predominantly transcribed. Selective pressure for zero erucic acid, low glucosinolate, high oleic acid and

  5. Photosynthesis of C3, C3–C4, and C4 grasses at glacial CO2

    PubMed Central

    Pinto, Harshini; Sharwood, Robert E.; Tissue, David T.; Ghannoum, Oula

    2014-01-01

    Most physiology comparisons of C3 and C4 plants are made under current or elevated concentrations of atmospheric CO2 which do not reflect the low CO2 environment under which C4 photosynthesis has evolved. Accordingly, photosynthetic nitrogen (PNUE) and water (PWUE) use efficiency, and the activity of the photosynthetic carboxylases [Rubisco and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [NADP-malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] were compared in eight C4 grasses with NAD-ME, PCK, and NADP-ME subtypes, one C3 grass, and one C3–C4 grass grown under ambient (400 μl l–1) and glacial (180 μl l–1) CO2. Glacial CO2 caused a smaller reduction of photosynthesis and a greater increase of stomatal conductance in C4 relative to C3 and C3–C4 species. Panicum bisulcatum (C3) acclimated to glacial [CO2] by doubling Rubisco activity, while Rubisco was unchanged in Panicum milioides (C3–C4), possibly due to its high leaf N and Rubisco contents. Glacial CO2 up-regulated Rubisco and PEPC activities in concert for several C4 grasses, while NADP-ME and PEP-CK activities were unchanged, reflecting the high control exerted by the carboxylases relative to the decarboxylases on the efficiency of C4 metabolism. Despite having larger stomatal conductance at glacial CO2, C4 species maintained greater PWUE and PNUE relative to C3–C4 and C3 species due to higher photosynthetic rates. Relative to other C4 subtypes, NAD-ME and PEP-CK grasses had the highest PWUE and PNUE, respectively; relative to C3, the C3–C4 grass had higher PWUE and similar PNUE at glacial CO2. Biomass accumulation was reduced by glacial CO2 in the C3 grass relative to the C3–C4 grass, while biomass was less reduced in NAD-ME grasses compared with NADP-ME and PCK grasses. Under glacial CO2, high resource use efficiency offers a key evolutionary advantage for the transition from C3 to C4 photosynthesis in water- and nutrient-limited environments. PMID:24723409

  6. Diversity in forms of C4 in the genus Cleome (Cleomaceae)

    PubMed Central

    Koteyeva, Nuria K.; Voznesenskaya, Elena V.; Roalson, Eric H.; Edwards, Gerald E.

    2011-01-01

    Background and Aims Cleomaceae is one of 19 angiosperm families in which C4 photosynthesis has been reported. The aim of the study was to determine the type, and diversity, of structural and functional forms of C4 in genus Cleome. Methods Plants of Cleome species were grown from seeds, and leaves were subjected to carbon isotope analysis, light and scanning electron microscopy, western blot analysis of proteins, and in situ immunolocalization for ribulose bisphosphate carboxylase oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC). Key Results Three species with C4-type carbon isotope values occurring in separate lineages in the genus (Cleome angustifolia, C. gynandra and C. oxalidea) were shown to have features of C4 photosynthesis in leaves and cotyledons. Immunolocalization studies show that PEPC is localized in mesophyll (M) cells and Rubisco is selectively localized in bundle sheath (BS) cells in leaves and cotyledons, characteristic of species with Kranz anatomy. Analyses of leaves for key photosynthetic enzymes show they have high expression of markers for the C4 cycle (compared with the C3–C4 intermediate C. paradoxa and the C3 species C. africana). All three are biochemically NAD-malic enzyme sub-type, with higher granal development in BS than in M chloroplasts, characteristic of this biochemical sub-type. Cleome gynandra and C. oxalidea have atriplicoid-type Kranz anatomy with multiple simple Kranz units around individual veins. However, C. angustifolia anatomy is represented by a double layer of concentric chlorenchyma forming a single compound Kranz unit by surrounding all the vascular bundles and water storage cells. Conclusions NAD-malic enzyme-type C4 photosynthesis evolved multiple times in the family Cleomaceae, twice with atriplicoid-type anatomy in compound leaves having flat, broad leaflets in the pantropical species C. gynandra and the Australian species C. oxalidea, and once by forming a single Kranz unit in compound leaves with

  7. Return current and proton emission from wire targets interacting with an intense short pulse laser

    NASA Astrophysics Data System (ADS)

    Beg, Farhat

    2004-05-01

    emission was also observed from an additional wire or foil. Simulations with the 3D tree code PEPC [1] and the 2-1/2 D PIC code OSIRIS [2] will be presented. [1] P. Gibbon, PEPC: Pretty Efficient Parallel Coulomb Solver, ZAM Technical Report FZJ-ZAM-IB-2003-05(2003), available online at http://www.fz-juelich.de /zam/ docs /autoren2003 /gibbon.html [2] R. Hemker, Ph.D. Thesis, UCLA, 2000.

  8. Effects of boron deficiency on major metabolites, key enzymes and gas exchange in leaves and roots of Citrus sinensis seedlings.

    PubMed

    Lu, Yi-Bin; Yang, Lin-Tong; Li, Yan; Xu, Jing; Liao, Tian-Tai; Chen, Yan-Bin; Chen, Li-Song

    2014-06-01

    Boron (B) deficiency is a widespread problem in many crops, including Citrus. The effects of B-deficiency on gas exchange, carbohydrates, organic acids, amino acids, total soluble proteins and phenolics, and the activities of key enzymes involved in organic acid and amino acid metabolism in 'Xuegan' [Citrus sinensis (L.) Osbeck] leaves and roots were investigated. Boron-deficient leaves displayed excessive accumulation of nonstructural carbohydrates and much lower CO2 assimilation, demonstrating feedback inhibition of photosynthesis. Dark respiration, concentrations of most organic acids [i.e., malate, citrate, oxaloacetate (OAA), pyruvate and phosphoenolpyruvate] and activities of enzymes [i.e., phosphoenolpyruvate carboxylase (PEPC), NAD-malate dehydrogenase, NAD-malic enzyme (NAD-ME), NADP-ME, pyruvate kinase (PK), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS), aconitase (ACO), NADP-isocitrate dehydrogenase (NADP-IDH) and hexokinase] involved in glycolysis, the tricarboxylic acid (TCA) cycle and the anapleurotic reaction were higher in B-deficient leaves than in controls. Also, total free amino acid (TFAA) concentration and related enzyme [i.e., NADH-dependent glutamate 2-oxoglutarate aminotransferase (NADH-GOGAT) and glutamate OAA transaminase (GOT)] activities were enhanced in B-deficient leaves. By contrast, respiration, concentrations of nonstructural carbohydrates and three organic acids (malate, citrate and pyruvate), and activities of most enzymes [i.e., PEPC, NADP-ME, PK, PEPP, CS, ACO, NAD-isocitrate dehydrogenase, NADP-IDH and hexokinase] involved in glycolysis, the TCA cycle and the anapleurotic reaction, as well as concentration of TFAA and activities of related enzymes (i.e., nitrate reductase, NADH-GOGAT, glutamate pyruvate transaminase and glutamine synthetase) were lower in B-deficient roots than in controls. Interestingly, leaf and root concentration of total phenolics increased, whereas that of total soluble protein decreased

  9. Comparing photosynthetic characteristics of Isoetes sinensis Palmer under submerged and terrestrial conditions

    PubMed Central

    Yang, Tao; Liu, Xing

    2015-01-01

    Crassulacean acid metabolism (CAM) is widespread in terrestrial and aquatic species, plastic in response to environmental changes. Isoetes L. is one of the earliest basal vascular plants and CAM is popular in this genus. Isoetes sinensis Palmer is an amphibious species, alternating frequently between terrestrial and aquatic environments. Given this, we investigated and compared photosynthetic characteristics over a diurnal cycle under submerged condition (SC) and terrestrial condition (TC). The results suggest that I. sinensis possesses a stronger CAM capacity under SC. Compared with under TC, titratable acidity levels and organic acid concentrations were more enriched under SC, whereas soluble sugar or starch and protein levels were lower under SC. Transcript analyses for nine photosynthetic genes revealed that CAM-associated genes possessed high transcripts under SC, but C3-related transcripts were highly expressed under TC. In addition, the enzyme activity measurements demonstrated that PEPC activity over a diurnal cycle was slightly higher under SC, whereas Rubisco activity during the daytime was greater under TC. This comprehensive study probably facilitates general understandings about the CAM photosynthetic characteristics of Isoetes in response to the environmental changes. PMID:26634994

  10. Differential response of NADP-dehydrogenases and carbon metabolism in leaves and roots of two durum wheat (Triticum durum Desf.) cultivars (Karim and Azizi) with different sensitivities to salt stress.

    PubMed

    Bouthour, Donia; Kalai, Tawba; Chaffei, Haouari C; Gouia, Houda; Corpas, Francisco J

    2015-05-01

    Wheat (Triticum durum Desf.) is a common Mediterranean species of considerable agronomic importance. Salinity is one of the major threats to sustainable agricultural production mainly because it limits plant productivity. After exposing the Karim and Azizi durum wheat cultivars, which are of agronomic significance in Tunisia, to 100mM NaCl salinity, growth parameters (dry weight and length), proline content and chlorophylls were evaluated in their leaves and roots. In addition, we analyzed glutathione content and key enzymatic activities, including phosphoenolpyruvate carboxylase (PEPC), NADP-isocitrate dehydrogenase (NADP-ICDH), NADP-malic enzyme (NADP-ME), glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH), involved in the carbon metabolism and NADPH-generating system. The sensitivity index indicates that cv Karim was more tolerant to salinity than cv Azizi. This higher tolerance was corroborated at the biochemical level, as cv Karim showed a greater capacity to accumulate proline, especially in leaves, while the enzyme activities studied were differentially regulated in both organs, with NADP-ICDH being the only activity to be unaffected in all organs. In summary, the data indicate that higher levels of proline accumulation and the differential responses of some key enzymes involved in the carbon metabolism and NADPH regeneration contribute to the salinity tolerance mechanism and lead to increased biomass accumulation in cv Karim.

  11. Generation of marker-free Bt transgenic indica rice and evaluation of its yellow stem borer resistance.

    PubMed

    Kumar, S; Arul, L; Talwar, D

    2010-01-01

    We report on generation of marker-free (‘clean DNA’) transgenic rice (Oryza sativa), carrying minimal gene-expression-cassettes of the genes of interest, and evaluation of its resistance to yellow stem borer Scirpophaga incertulas (Lepidoptera: Pyralidae). The transgenic indica rice harbours a translational fusion of 2 different Bacillus thuringiensis (Bt) genes, namely cry1B-1Aa, driven by the green-tissue-specific phosphoenol pyruvate carboxylase (PEPC) promoter. Mature seed-derived calli of an elite indica rice cultivar Pusa Basmati-1 were co-bombarded with gene-expression-cassettes (clean DNA fragments) of the Bt gene and the marker hpt gene, to generate marker-free transgenic rice plants. The clean DNA fragments for bombardment were obtained by restriction digestion and gel extraction. Through biolistic transformation, 67 independent transformants were generated. Transformation frequency reached 3.3%, and 81% of the transgenic plants were co-transformants. Stable integration of the Bt gene was confirmed, and the insert copy number was determined by Southern analysis. Western analysis and ELISA revealed a high level of Bt protein expression in transgenic plants. Progeny analysis confirmed stable inheritance of the Bt gene according to the Mendelian (3:1) ratio. Insect bioassays revealed complete protection of transgenic plants from yellow stem borer infestation. PCR analysis of T2 progeny plants resulted in the recovery of up to 4% marker-free transgenic rice plants.

  12. Advancing oleaginous microorganisms to produce lipid via metabolic engineering technology.

    PubMed

    Liang, Ming-Hua; Jiang, Jian-Guo

    2013-10-01

    With the depletion of global petroleum and its increasing price, biodiesel has been becoming one of the most promising biofuels for global fuels market. Researchers exploit oleaginous microorganisms for biodiesel production due to their short life cycle, less labor required, less affection by venue, and easier to scale up. Many oleaginous microorganisms can accumulate lipids, especially triacylglycerols (TAGs), which are the main materials for biodiesel production. This review is covering the related researches on different oleaginous microorganisms, such as yeast, mold, bacteria and microalgae, which might become the potential oil feedstocks for biodiesel production in the future, showing that biodiesel from oleaginous microorganisms has a great prospect in the development of biomass energy. Microbial oils biosynthesis process includes fatty acid synthesis approach and TAG synthesis approach. In addition, the strategies to increase lipids accumulation via metabolic engineering technology, involving the enhancement of fatty acid synthesis approach, the enhancement of TAG synthesis approach, the regulation of related TAG biosynthesis bypass approaches, the blocking of competing pathways and the multi-gene approach, are discussed in detail. It is suggested that DGAT and ME are the most promising targets for gene transformation, and reducing PEPC activity is observed to be beneficial for lipid production.

  13. Interactions between light intensity and phosphorus nutrition affect the phosphate-mining capacity of white lupin (Lupinus albus L.).

    PubMed

    Cheng, Lingyun; Tang, Xiaoyan; Vance, Carroll P; White, Philip J; Zhang, Fusuo; Shen, Jianbo

    2014-07-01

    Light intensity affects photosynthetic carbon (C) fixation and the supply of carbon to roots. To evaluate interactions between carbon supply and phosphorus (P) supply, effects of light intensity on sucrose accumulation, root growth, cluster root formation, carboxylate exudation, and P uptake capacity were studied in white lupin (Lupinus albus L.) grown hydroponically with either 200 µmol m(-2) s(-1) or 600 µmol m(-2) s(-1) light and a sufficient (50 µM P) or deficient (1 µM P) P supply. Plant biomass and root:shoot ratio increased with increasing light intensity, particularly when plants were supplied with sufficient P. Both low P supply and increasing light intensity increased the production of cluster roots and citrate exudation. Transcripts of a phosphoenol pyruvate carboxylase gene (LaPEPC3) in cluster roots (which is related to the exudation of citrate), transcripts of a phosphate transporter gene (LaPT1), and P uptake all increased with increasing light intensity, under both P-sufficient and P-deficient conditions. Across all four experimental treatments, increased cluster root formation and carboxylate exudation were associated with lower P concentration in the shoot and greater sucrose concentration in the roots. It is suggested that C in excess of shoot growth capabilities is translocated to the roots as sucrose, which serves as both a nutritional signal and a C-substrate for carboxylate exudation and cluster root formation.

  14. Adaxial/abaxial specification in the regulation of photosynthesis and stomatal opening with respect to light orientation and growth with CO2 enrichment in the C4 species Paspalum dilatatum.

    PubMed

    Soares, Ana Sofia; Driscoll, Simon P; Olmos, Enrique; Harbinson, Jeremy; Arrabaça, Maria Celeste; Foyer, Christine H

    2008-01-01

    Whole-plant morphology, leaf structure and composition were studied together with the effects of light orientation on the dorso-ventral regulation of photosynthesis and stomatal conductance in Paspalum dilatatum cv. Raki plants grown for 6 wk at either 350 or 700 microl l(-1) CO(2). Plant biomass was doubled as a result of growth at high CO(2) and the shoot:root ratio was decreased. Stomatal density was increased in the leaves of the high CO(2)-grown plants, which had greater numbers of smaller stomata and more epidermal cells on the abaxial surface. An asymmetric surface-specific regulation of photosynthesis and stomatal conductance was observed with respect to light orientation. This was not caused by dorso-ventral variations in leaf structure, the distribution of phosphoenolpyruvate carboxylase (PEPC) and ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) proteins or light absorptance, transmittance or reflectance. Adaxial/abaxial specification in the regulation of photosynthesis results from differential sensitivity of stomatal opening to light orientation and fixed gradients of enzyme activation across the leaf.

  15. A novel reference plasmid for the qualitative detection of genetically modified rice in food and feed.

    PubMed

    Li, Liang; Dong, Mei; An, Na; Liang, Lixia; Wan, Yusong; Jin, Wujun

    2015-01-01

    Rice is one of the most important food crops in the world. Genetically modified (GM) technology has been used in rice to confer herbicide tolerance and pathogen or insect resistance. China invests heavily in research on GM rice. By the end of 2014, at least 250 transgenic rice lines had been developed in China. To monitor the presence of GM rice in food and feed, we collected information on foreign elements from 250 transgenic rice lines and found 5 elements, including the Agrobacterium tumefaciens nopaline synthase terminator (T-NOS), the cauliflower mosaic virus 35S promoter (CaMV35S), the ubiquitin gene (Ubi), the bar gene, and the hygromycin phosphotransferase gene (Hpt), that are commonly present in GM rice. Therefore, we constructed a novel plasmid (pBJGMM001) that contains fragments of these elements and two endogenous reference genes (the sucrose phosphate synthase gene, SPS, and the phosphoenolpyruvate carboxylase gene, PEPC). pBJGMM001 can serve as a standard for detecting 96% of GM rice lines in China. The primers, amplicons, reaction mixture, and PCR program were developed based on Chinese National Standards. The protocol was validated and determined to be suitable for practical use in monitoring and identifying GM rice.

  16. Evidence of Coexistence of C3 and C4 Photosynthetic Pathways in a Green-Tide-Forming Alga, Ulva prolifera

    PubMed Central

    Zhang, Xiaowen; Xu, Dong; Mou, Shanli; Cao, Shaona; Zheng, Zhou; Miao, Jinlai; Ye, Naihao

    2012-01-01

    Ulva prolifera, a typical green-tide-forming alga, can accumulate a large biomass in a relatively short time period, suggesting that photosynthesis in this organism, particularly its carbon fixation pathway, must be very efficient. Green algae are known to generally perform C3 photosynthesis, but recent metabolic labeling and genome sequencing data suggest that they may also perform C4 photosynthesis, so C4 photosynthesis might be more wide-spread than previously anticipated. Both C3 and C4 photosynthesis genes were found in U. prolifera by transcriptome sequencing. We also discovered the key enzymes of C4 metabolism based on functional analysis, such as pyruvate orthophosphate dikinase (PPDK), phosphoenolpyruvate carboxylase (PEPC), and phosphoenolpyruvate carboxykinase (PCK). To investigate whether the alga operates a C4-like pathway, the expression of rbcL and PPDK and their enzyme activities were measured under various forms and intensities of stress (differing levels of salinity, light intensity, and temperature). The expression of rbcL and PPDK and their enzyme activities were higher under adverse circumstances. However, under conditions of desiccation, the expression of rbcL and ribulose-1, 5-biphosphate carboxylase (RuBPCase) activity was lower, whereas that of PPDK was higher. These results suggest that elevated PPDK activity may alter carbon metabolism and lead to a partial operation of C4-type carbon metabolism in U. prolifera, probably contributing to its wide distribution and massive, repeated blooms in the Yellow Sea. PMID:22616009

  17. Evidence of coexistence of C₃ and C₄ photosynthetic pathways in a green-tide-forming alga, Ulva prolifera.

    PubMed

    Xu, Jianfang; Fan, Xiao; Zhang, Xiaowen; Xu, Dong; Mou, Shanli; Cao, Shaona; Zheng, Zhou; Miao, Jinlai; Ye, Naihao

    2012-01-01

    Ulva prolifera, a typical green-tide-forming alga, can accumulate a large biomass in a relatively short time period, suggesting that photosynthesis in this organism, particularly its carbon fixation pathway, must be very efficient. Green algae are known to generally perform C₃ photosynthesis, but recent metabolic labeling and genome sequencing data suggest that they may also perform C₄ photosynthesis, so C₄ photosynthesis might be more wide-spread than previously anticipated. Both C₃ and C₄ photosynthesis genes were found in U. prolifera by transcriptome sequencing. We also discovered the key enzymes of C₄ metabolism based on functional analysis, such as pyruvate orthophosphate dikinase (PPDK), phosphoenolpyruvate carboxylase (PEPC), and phosphoenolpyruvate carboxykinase (PCK). To investigate whether the alga operates a C₄-like pathway, the expression of rbcL and PPDK and their enzyme activities were measured under various forms and intensities of stress (differing levels of salinity, light intensity, and temperature). The expression of rbcL and PPDK and their enzyme activities were higher under adverse circumstances. However, under conditions of desiccation, the expression of rbcL and ribulose-1, 5-biphosphate carboxylase (RuBPCase) activity was lower, whereas that of PPDK was higher. These results suggest that elevated PPDK activity may alter carbon metabolism and lead to a partial operation of C₄-type carbon metabolism in U. prolifera, probably contributing to its wide distribution and massive, repeated blooms in the Yellow Sea.

  18. Seasonal dynamics in the stable carbon isotope composition δ¹³C from non-leafy branch, trunk and coarse root CO₂ efflux of adult deciduous (Fagus sylvatica) and evergreen (Picea abies) trees.

    PubMed

    Kuptz, Daniel; Matyssek, Rainer; Grams, Thorsten E E

    2011-03-01

    Respiration is a substantial driver of carbon (C) flux in forest ecosystems and stable C isotopes provide an excellent tool for its investigation. We studied seasonal dynamics in δ¹³C of CO₂ efflux (δ¹³C(E)) from non-leafy branches, upper and lower trunks and coarse roots of adult trees, comparing deciduous Fagus sylvatica (European beech) with evergreen Picea abies (Norway spruce). In both species, we observed strong and similar seasonal dynamics in the δ¹³C(E) of above-ground plant components, whereas δ¹³C(E) of coarse roots was rather stable. During summer, δ¹³C(E) of trunks was about -28.2‰ (Beech) and -26.8‰ (Spruce). During winter dormancy, δ¹³C(E) increased by 5.6-9.1‰. The observed dynamics are likely related to a switch from growth to starch accumulation during fall and remobilization of starch, low TCA cycle activity and accumulation of malate by PEPc during winter. The seasonal δ¹³C(E) pattern of branches of Beech and upper trunks of Spruce was less variable, probably because these organs were additionally supplied by winter photosynthesis. In view of our results and pervious studies, we conclude that the pronounced increases in δ¹³C(E) of trunks during the winter results from interrupted access to recent photosynthates.

  19. Intrauterine fetal brain NMR spectroscopy: 1H and 31P studies in rats

    SciTech Connect

    Nakada, T.; Kwee, I.L.; Suzuki, N.; Houkin, K. )

    1989-11-01

    Fetal brain metabolism was investigated in utero noninvasively using multinuclear nuclear magnetic resonance spectroscopy in rats at two representative prenatal stages: early (17-18 days) and late (20-21 days) stages. Phosphorus-31 (31P) spectroscopy revealed that phosphocreatine is significantly lower in the early stage and increases to the level of early neonates by the late prenatal stage. Intracellular pH at the early stage was found to be strikingly high (7.52 +/- 0.21) and decreased to a level similar to that of neonates by the late stage (7.29 +/- 0.07). Phosphomonoester levels at both stages were similar to the values reported for early neonates. Water-suppressed proton (1H) spectroscopy demonstrated a distinctive in vivo fetal brain spectral pattern characterized by low levels of N-acetyl aspartate and high levels of taurine. High-resolution proton spectroscopy and homonuclear chemical-shift correlate spectroscopy of brain perchloric acid extracts confirmed these in vivo findings. In vitro 31P spectroscopy of acidified chloroform methanol extracts showed the characteristic membrane phospholipid profiles of fetal brain. The phosphatidylethanolamine (PE)-to-phosphatidylcholine (PC) ratio (PE/PC) did not show significant changes between the two stages at 0.40 +/- 0.11, a value similar to that of early neonates.

  20. Overexpression of the ascorbate peroxidase gene from eggplant and sponge gourd enhances flood tolerance in transgenic Arabidopsis.

    PubMed

    Chiang, Chih-Ming; Chen, Chiu-Chen; Chen, Shi-Peng; Lin, Kuan-Hung; Chen, Li-Ru; Su, Yu-Huei; Yen, His-Cheng

    2017-03-01

    Previously, we found that the flood resistance of eggplant (Solanum melongena) and sponge gourd (Luffa cylindrica) enhanced ascorbate peroxidase (APX) activity under flooding, and consequently, both the SmAPX and LcAPX genes were cloned. In this study, the SmAPX and LcAPX genes were transferred under a ubiquitin promoter to Arabidopsis (At) via Agrobacterium tumefaciens. The expression and amount of APX and APX activities of the SmAPX and LcAPX transgenic lines were significantly higher than those of non-transgenic (NT) plants under a waterlogged condition. Furthermore, the SmAPX, LcAPX, At-sucrose synthases (SUS)-1, phosphoenolpyruvate carboxylase (PEPC), and lactate dehydrogenase (LDH) genes were overexpressed in all transgenic Arabidopsis lines after flooding treatment. Compared to NT plants, the malondialdehyde (MDA) contents and H2O2 accumulation were significantly lower, but germination rates were significantly higher in all transgenic lines with higher APX activity, indicating that the overexpression of SmAPX and LcAPX in Arabidopsis could enhance flood tolerance by eliminating H2O2. Moreover, Arabidopsis seedlings overexpressing SmAPX and LcAPX also displayed greater resistance to flooding and less oxidative injury than NT plants subjected to flooding condition.

  1. Genetic relationships among Enterococcus faecalis isolates from different sources as revealed by multilocus sequence typing.

    PubMed

    Chen, X; Song, Y Q; Xu, H Y; Menghe, B L G; Zhang, H P; Sun, Z H

    2015-08-01

    Enterococcus faecalis is part of the natural gut flora of humans and other mammals; some isolates are also used in food production. So, it is important to evaluate the genetic diversity and phylogenetic relationships among E. faecalis isolates from different sources. Multilocus sequence typing protocol was used to compare 39 E. faecalis isolates from Chinese traditional food products (including dairy products, acidic gruel) and 4 published E. faecalis isolates from other sources including human-derived isolates employing 5 housekeeping genes (groEL, clpX, recA, rpoB, and pepC). A total of 23 unique sequence types were identified, which were grouped into 5 clonal complexes and 10 singletons. The value of standardized index of association of the alleles (IA(S)=0.1465) and network structure indicated a high frequency of intraspecies recombination across these isolates. Enterococcus faecalis lineages also exhibited clearly source-clustered distributions. The isolates from dairy source were clustered together. However, the relationship between isolates from acidic gruel and one isolate from a human source was close. The MLST scheme presented in this study provides a sharable and continuously growing sequence database enabling global comparison of strains from different sources, and will further advance our understanding of the microbial ecology of this important species.

  2. Metabolic networks to generate pyruvate, PEP and ATP from glycerol in Pseudomonas fluorescens.

    PubMed

    Alhasawi, Azhar; Thomas, Sean C; Appanna, Vasu D

    2016-04-01

    Glycerol is a major by-product of the biodiesel industry. In this study we report on the metabolic networks involved in its transformation into pyruvate, phosphoenolpyruvate (PEP) and ATP. When the nutritionally-versatile Pseudomonas fluorescens was exposed to hydrogen peroxide (H2O2) in a mineral medium with glycerol as the sole carbon source, the microbe reconfigured its metabolism to generate adenosine triphosphate (ATP) primarily via substrate-level phosphorylation (SLP). This alternative ATP-producing stratagem resulted in the synthesis of copious amounts of PEP and pyruvate. The production of these metabolites was mediated via the enhanced activities of such enzymes as pyruvate carboxylase (PC) and phosphoenolpyruvate carboxylase (PEPC). The high energy PEP was subsequently converted into ATP with the aid of pyruvate phosphate dikinase (PPDK), phosphoenolpyruvate synthase (PEPS) and pyruvate kinase (PK) with the concomitant formation of pyruvate. The participation of the phospho-transfer enzymes like adenylate kinase (AK) and acetate kinase (ACK) ensured the efficiency of this O2-independent energy-generating machinery. The increased activity of glycerol dehydrogenase (GDH) in the stressed bacteria provided the necessary precursors to fuel this process. This H2O2-induced anaerobic life-style fortuitously evokes metabolic networks to an effective pathway that can be harnessed into the synthesis of ATP, PEP and pyruvate. The bioconversion of glycerol to pyruvate will offer interesting economic benefit.

  3. A Novel Reference Plasmid for the Qualitative Detection of Genetically Modified Rice in Food and Feed

    PubMed Central

    Li, Liang; Dong, Mei; An, Na; Liang, Lixia; Wan, Yusong; Jin, Wujun

    2015-01-01

    Rice is one of the most important food crops in the world. Genetically modified (GM) technology has been used in rice to confer herbicide tolerance and pathogen or insect resistance. China invests heavily in research on GM rice. By the end of 2014, at least 250 transgenic rice lines had been developed in China. To monitor the presence of GM rice in food and feed, we collected information on foreign elements from 250 transgenic rice lines and found 5 elements, including the Agrobacterium tumefaciens nopaline synthase terminator (T-NOS), the cauliflower mosaic virus 35S promoter (CaMV35S), the ubiquitin gene (Ubi), the bar gene, and the hygromycin phosphotransferase gene (Hpt), that are commonly present in GM rice. Therefore, we constructed a novel plasmid (pBJGMM001) that contains fragments of these elements and two endogenous reference genes (the sucrose phosphate synthase gene, SPS, and the phosphoenolpyruvate carboxylase gene, PEPC). pBJGMM001 can serve as a standard for detecting 96% of GM rice lines in China. The primers, amplicons, reaction mixture, and PCR program were developed based on Chinese National Standards. The protocol was validated and determined to be suitable for practical use in monitoring and identifying GM rice. PMID:26495318

  4. The effect of nutrition pattern alteration on Chlorella pyrenoidosa growth, lipid biosynthesis-related gene transcription.

    PubMed

    Fan, Jianhua; Cui, Yanbin; Zhou, Yang; Wan, Minxi; Wang, Weiliang; Xie, Jingli; Li, Yuanguang

    2014-07-01

    Heterotrophy to photoautotrophy transition leads to the accumulation of lipids in Chlorella, which has potential to produce both healthy food and biofuels. Therefore, it is of key interest to study the metabolism shift and gene expression changes that influenced by the transition. Both total and neutral lipids contents were increased rapidly within 48 h after the switch to light environment, from 24.5% and 18.0% to 35.3% and 27.4%, respectively, along with the sharp decline of starch from 42.3% to 10.4% during 24h photoinduction phase. By analyzing the correlation between lipid content and gene expression, results revealed several genes viz. me g3137, me g6562, pepc g6833, dgat g3280 and dgat g7566, which encode corresponding enzymes in the de novo lipid biosynthesis pathway, are highly related to lipid accumulation and might be exploited as target genes for genetic modification. These results represented the feasibility of lipid production through trophic converting cultivation.

  5. New estimates on the magnitude of fractionation during photorespiration

    NASA Astrophysics Data System (ADS)

    Seibt, U.; Lanigan, G.; Betson, N.; Griffiths, H.

    2008-12-01

    We report new estimates of the carbon isotope fractionation during photorespiration for three Senecio species. We determined the contributions of different processes to net 13C discrimination during photosynthesis by comparing observed discrimination to predictions derived from gas exchange measurements. The rate of photorespiration was manipulated by altering the O2 partial pressure in the air surrounding the leaves. The fractionation factors for photorespiration (f) and net carboxylation by Rubisco and PEPc (b), and mesophyll conductance (gi) were treated as unknowns and determined simultaneously for all measurements. We propose this as alternative approach to analyse measurements under field conditions when mesophyll conductance and fractionation factors are not known, or cannot be determined in separate experiments. Good agreement between predicted and observed discrimination was achieved with f of 11.6 permil, b of 26 permil, and gi between 0.22 and 0.27 mol m-2 s-1. Our result for f is close to recent theoretical estimates. Photorespiratory fractionation decreases net 13C discrimination by about 1.2 permil on average under field conditions, which should be taken into account when partitioning net CO2 exchange of ecosystems into gross fluxes of photosynthesis and respiration.

  6. Compensation processes of Aleppo pine (Pinus halepensis Mill.) to ozone exposure and drought stress.

    PubMed

    Inclán, R; Gimeno, B S; Dizengremel, P; Sanchez, M

    2005-10-01

    A long-term experiment was performed to study the effects of O3 and drought-stress (DS) on Aleppo pine seedlings (Pinus halepensis Mill.) exposed in open-top chambers. Ozone reduced gas exchange rates, ribulose-1,5-biphosphate carboxylase/oxygenase activity (Rubisco), aboveground C and needle N concentrations and C/N ratio and Ca concentrations of the twigs under 3 mm (twigs<3) and the aerial biomass. Also it increased phosphoenolpyruvate carboxylase (PEPc) and N and K concentrations of the twigs<3. Water stress decreased gas exchange rates, predawn needle water potential (PsiPd), C/N ratio, twigs<3 Ca, plant growth, aerial biomass and increased N, twigs with a diameter above 3 mm P and Mg concentrations. The combined exposure to both stresses increased N concentrations of twigs<3 and roots and aboveground biomass K content and decreased root C, maximum daily assimilation rate and instantaneous water use efficiency. The sensitivity of Aleppo pine to both stresses is determined by plant internal resource allocation and compensation mechanisms to cope with stress.

  7. Ozone exposure and flux-based response functions for photosynthetic traits in wheat, maize and poplar.

    PubMed

    Bagard, Matthieu; Jolivet, Yves; Hasenfratz-Sauder, Marie-Paule; Gérard, Joëlle; Dizengremel, Pierre; Le Thiec, Didier

    2015-11-01

    Ozone exposure- and dose-response relationships based on photosynthetic leaf traits (CO2 assimilation, chlorophyll content, Rubisco and PEPc activities) were established for wheat, maize and poplar plants grown in identical controlled conditions, providing a comparison between crop and tree species, as well as between C3 and C4 plants. Intra-specific variability was addressed by comparing two wheat cultivars with contrasting ozone tolerance. Depending on plant models and ozone levels, first-order, second-order and segmented linear regression models were used to derive ozone response functions. Overall, flux-based functions appeared superior to exposure-based functions in describing the data, but the improvement remained modest. The best fit was obtained using the POD0.5 for maize and POD3 for poplar. The POD6 appeared relevant for wheat, although intervarietal differences were found. Our results suggest that taking into account the dynamics of leaf antioxidant capacity could improve current methods for ozone risk assessment for plants.

  8. Error-related event-related potentials in children with Attention-Deficit Hyperactivity Disorder, Oppositional Defiant Disorder, Reading Disorder, and Math Disorder

    PubMed Central

    Burgio-Murphy, Andrea; Klorman, Rafael; Shaywitz, Sally E.; Fletcher, Jack M.; Marchione, Karen E.; Holahan, John; Stuebing, Karla K.; Thatcher, Joan E.; Shaywitz, Bennett A.

    2009-01-01

    We studied Error-Related Negativity (ERN) and Error Positivity (Pe) during a discrimination task in 319 unmedicated children divided into subtypes of ADHD (Not-ADHD/ Inattentive/ Combined), Learning Disorder (Not-LD/Reading/Math/Reading+Math), and Oppositional Defiant Disorder. Response-locked ERPs contained a frontocentral ERN and posterior Pe. Error-related Negativity and Positivity exhibited larger amplitude and later latency than corresponding waves for correct responses matched on reaction time. ADHD did not affect performance on the task. The ADHD/Combined sample exceeded controls in ERN amplitude, perhaps reflecting patients’ adaptive monitoring efforts. Compared with controls, subjects with Reading Disorder and Reading+Math Disorder performed worse on the task and had marginally more negative Correct-Related Negativities. In contrast, Pe/Pc was smaller in children with Reading+Math Disorder than among subjects with Reading Disorder and Not-LD participants; this nonspecific finding is not attributable to error processing. The results reflect anomalies in error processing in these disorders but further research is needed to address inconsistencies in the literature. PMID:17257731

  9. Error-related event-related potentials in children with attention-deficit hyperactivity disorder, oppositional defiant disorder, reading disorder, and math disorder.

    PubMed

    Burgio-Murphy, Andrea; Klorman, Rafael; Shaywitz, Sally E; Fletcher, Jack M; Marchione, Karen E; Holahan, John; Stuebing, Karla K; Thatcher, Joan E; Shaywitz, Bennett A

    2007-04-01

    We studied error-related negativity (ERN) and error positivity (Pe) during a discrimination task in 319 unmedicated children divided into subtypes of ADHD (Not-ADHD/inattentive/combined), learning disorder (Not-LD/reading/math/reading+math), and oppositional defiant disorder. Response-locked ERPs contained a frontocentral ERN and posterior Pe. Error-related negativity and positivity exhibited larger amplitude and later latency than corresponding waves for correct responses matched on reaction time. ADHD did not affect performance on the task. The ADHD/combined sample exceeded controls in ERN amplitude, perhaps reflecting patients' adaptive monitoring efforts. Compared with controls, subjects with reading disorder and reading+math disorder performed worse on the task and had marginally more negative correct-related negativities. In contrast, Pe/Pc was smaller in children with reading+math disorder than among subjects with reading disorder and Not-LD participants; this nonspecific finding is not attributable to error processing. The results reflect anomalies in error processing in these disorders but further research is needed to address inconsistencies in the literature.

  10. Interactive response of photosynthetic characteristics in Haloxylon ammodendron and Hedysarum scoparium exposed to soil water and air vapor pressure deficits.

    PubMed

    Gong, Chunmei; Wang, Jiajia; Hu, Congxia; Wang, Junhui; Ning, Pengbo; Bai, Juan

    2015-08-01

    C4 plants possess better drought tolerance than C3 plants. However, Hedysarum scoparium, a C3 species, is dominant and widely distributed in the desert areas of northwestern China due to its strong drought tolerance. This study compared it with Haloxylon ammodendron, a C4 species, regarding the interactive effects of drought stress and different leaf-air vapor pressure deficits. Variables of interest included gas exchange, the activity levels of key C4 photosynthetic enzymes, and cellular anatomy. In both species, gas exchange parameters were more sensitive to high vapor pressure deficit than to strong water stress, and the net CO2 assimilation rate (An) was enhanced as vapor pressure deficits increased. A close relationship between An and stomatal conductance (gs) suggested that the species shared a similar response mechanism. In H. ammodendron, the activity levels of key C4 enzymes were higher, including those of phosphoenolpyruvate carboxylase (PEPC) and nicotinamide adenine dinucleotide phosphate-malate enzyme (NADP-ME), whereas in H. scoparium, the activity level of nicotinamide adenine dinucleotide-malate enzyme (NAD-ME) was higher. Meanwhile, H. scoparium utilized adaptive structural features, including a larger relative vessel area and a shorter distance from vein to stomata, which facilitated the movement of water. These findings implied that some C4 biochemical pathways were present in H. scoparium to respond to environmental challenges.

  11. Fe deficiency induced changes in rice (Oryza sativa L.) thylakoids.

    PubMed

    Wang, Yuwen; Xu, Chao; Li, Kang; Cai, Xiaojie; Wu, Min; Chen, Guoxiang

    2017-01-01

    Iron deficiency is an important abiotic stress that limits productivity of crops all over the world. We selected a hybrid rice (Oryza sativa L.), LYPJ, which is super high-yield and widely cultured in China, to investigate changes in the components and structure of thylakoid membranes and photosynthetic performance in response to iron deficiency. Our results demonstrated that photosystem I (PSI) is the primary target for iron deficiency, while the changes in photosystem II (PSII) are important for rebuilding a balance in disrupted energy utilization and dissipation caused by differential degradation of photosynthetic components. The result of immunoblot analysis suggested that the core subunit PsaA declined drastically, while PsbA remained relatively stable. Furthermore, several organizational changes of the photosynthetic apparatus were found by BN-PAGE, including a marked decrease in the PSI core complexes, the Cytb 6 /f complex, and the trimeric form of the LHCII antenna, consistent with the observed unstacking grana. The fluorescence induction analysis indicated a descending PSII activity with energy dissipation enhanced markedly. In addition, we proposed that the crippled CO2 assimilation could be compensated by the enhanced of phosphoenolpyruvate carboxylase (PEPC), which is suggested by the decreased ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and photosynthetic efficiency.

  12. Responses of growth, antioxidants and gene expression in smooth cordgrass (Spartina alterniflora) to various levels of salinity.

    PubMed

    Courtney, Abigail J; Xu, Jichen; Xu, Yan

    2016-02-01

    Salinity is a major environmental factor limiting the productivity and quality of crop plants. While most cereal crops are salt-sensitive, several halophytic grasses are able to maintain their growth under saline conditions. Elucidating the mechanisms for salinity responses in halophytic grasses would contribute to the breeding of salt-tolerant cereal and turf species belonging to the Poaceae family. Smooth cordgrass (Spartina alterniflora) is a dominant native halophytic grass in the Hackensack Meadowlands, the coastal salt marshes located in northeastern New Jersey. The goals of this study were to examine the growth pattern of S. alterniflora in a salinity gradient and identify an optimal range of salinity for its maximal growth. The regulation of its antioxidant system and gene expression under supraoptimal salinity conditions was also investigated. Our results showed that a salinity of 4 parts per thousand (ppt) (68 mM) was most favorable for the growth of S. alterniflora, followed by a non-salt environment. S. alterniflora responded to salts in the environment by regulating antioxidant enzyme activities and the expression of stress-induced proteins such as ALDH, HVA22 and PEPC. The plant may tolerate salinity up to the concentration of sea water, but any salinity above 12 ppt retarded its growth and altered the expression of genes encoding critical proteins.

  13. Hybrid Tamarix widespread in U.S. invasion and undetected in native Asian range

    PubMed Central

    Gaskin, John F.; Schaal, Barbara A.

    2002-01-01

    Biological invasions are drastically altering natural habitats and threatening biodiversity on both local and global levels. In one of the United States' worst invasions, Eurasian Tamarix plant species have spread rapidly to dominate over 600,000 riparian and wetland hectares. The largest Tamarix invasion consists of Tamarix chinensis and Tamarix ramosissima, two morphologically similar species. To clarify the identity, origins, and population structuring of this invasion, we analyzed DNA sequence data from an intron of a nuclear gene, phosphoenolpyruvate carboxylase (PepC). This intron proved to be highly variable at the population level, and the 269 native and invasive specimens yielded 58 haplotypes, from which we constructed a gene genealogy. Only four of these haplotypes were common to both the U.S. and Eurasia. Surprisingly, we found that the most common plant in this U.S. invasion is a hybrid combination of two species-specific genotypes that were geographically isolated in their native Eurasian range. Less extensive hybrids exist in the invasion, involving combinations of T. ramosissima and T. chinensis with Tamarix parviflora and Tamarix gallica. The presence of potentially novel hybrids in the U.S. illustrates how importation of exotics can alter population structures of species and contribute to invasions. PMID:12177412

  14. Limits to Open Class Performance?

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    2007-01-01

    This viewgraph presentation describes the limits to open class performance. The contents include: 1) Standard Class; 2) 15m/Racing Class; 3) Open Class; and 4) Design Solutions associated with assumptions, limiting parameters, airfoil performance, current trends, and analysis.

  15. 13 CFR 108.1840 - Computation of NMVC Company's Capital Impairment Percentage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Class 2 Appreciation are pledged or encumbered in any way, you must reduce the Adjusted Unrealized Gain computed in paragraph (d)(5) of this section by the amount of the related borrowing or other obligation,...

  16. 13 CFR 108.1840 - Computation of NMVC Company's Capital Impairment Percentage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Class 2 Appreciation are pledged or encumbered in any way, you must reduce the Adjusted Unrealized Gain computed in paragraph (d)(5) of this section by the amount of the related borrowing or other obligation,...

  17. University of Waterloo at TREC 2008 Blog Track

    DTIC Science & Technology

    2008-11-01

    sources, such as FrameNet [1], Levin’s verb classes [2], Hatzivassilouglou and McKeown’s list of subjective adjectives [3]. The developed methods...Levin’s verb classes [2] Beth Levin has categorized English verbs into semantic classes. Verbs from the following classes were used in our method... Verbs of psychological state (e.g., amaze, fascinate, bother, impress); • Verbs of desire (e.g., crave, yearn, need); • Judgment verbs (e.g

  18. Biophysical studies of cholesterol in unsaturated phospholipid model membranes

    NASA Astrophysics Data System (ADS)

    Williams, Justin Adam

    Cellular membranes contain a staggering diversity of lipids. The lipids are heterogeneously distributed to create regions, or domains, whose physical properties differ from the bulk membrane and play an essential role in modulating the function of resident proteins. Many basic questions pertaining to the formation of these lateral assemblies remain. This research employs model membranes of well-defined composition to focus on the potential role of polyunsaturated fatty acids (PUFAs) and their interaction with cholesterol (chol) in restructuring the membrane environment. Omega-3 (n-3) PUFAs are the main bioactive components of fish oil, whose consumption alleviates a variety of health problems by a molecular mechanism that is unclear. We hypothesize that the incorporation of PUFAs into membrane lipids and the effect they have on molecular organization may be, in part, responsible. Chol is a major constituent in the plasma membrane of mammals. It determines the arrangement and collective properties of neighboring lipids, driving the formation of domains via differential affinity for different lipids. The molecular organization of 1-[2H31]palmitoyl-2-eicosapentaenoylphosphatidylcholine (PEPC-d31) and 1-[2H31]palmitoyl-2-docosahexaenoylphosphatidylcholine (PDPC-d31) in membranes with sphingomyelin (SM) and chol (1:1:1 mol) was compared by solid-state 2H NMR spectroscopy. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids are the two major n-3 PUFAs found in fish oil, while PEPC-d31 and PDPC-d31 are phospholipids containing the respective PUFAs at the sn-2 position and a perdeuterated palmitic acid at the sn-1 position. Analysis of spectra recorded as a function of temperature indicates that in both cases, formation of PUFA-rich (less ordered) and SM-rich (more ordered) domains occurred. A surprisingly substantial proportion of PUFA was found to infiltrate the more ordered domain. There was almost twice as much DHA (65%) as EPA (30%). The implication is that n-3

  19. Clinical Performance and Management Outcomes with the DecisionDx-UM Gene Expression Profile Test in a Prospective Multicenter Study.

    PubMed

    Plasseraud, Kristen Meldi; Cook, Robert W; Tsai, Tony; Shildkrot, Yevgeniy; Middlebrook, Brooke; Maetzold, Derek; Wilkinson, Jeff; Stone, John; Johnson, Clare; Oelschlager, Kristen; Aaberg, Thomas M

    2016-01-01

    Uveal melanoma management is challenging due to its metastatic propensity. DecisionDx-UM is a prospectively validated molecular test that interrogates primary tumor biology to provide objective information about metastatic potential that can be used in determining appropriate patient care. To evaluate the continued clinical validity and utility of DecisionDx-UM, beginning March 2010, 70 patients were enrolled in a prospective, multicenter, IRB-approved study to document patient management differences and clinical outcomes associated with low-risk Class 1 and high-risk Class 2 results indicated by DecisionDx-UM testing. Thirty-seven patients in the prospective study were Class 1 and 33 were Class 2. Class 1 patients had 100% 3-year metastasis-free survival compared to 63% for Class 2 (log rank test p = 0.003) with 27.3 median follow-up months in this interim analysis. Class 2 patients received significantly higher-intensity monitoring and more oncology/clinical trial referrals compared to Class 1 patients (Fisher's exact test p = 2.1 × 10(-13) and p = 0.04, resp.). The results of this study provide additional, prospective evidence in an independent cohort of patients that Class 1 and Class 2 patients are managed according to the differential metastatic risk indicated by DecisionDx-UM. The trial is registered with Clinical Application of DecisionDx-UM Gene Expression Assay Results (NCT02376920).

  20. Genetic divergence and reproductive isolation between Anisakis brevispiculata and Anisakis physeteris (Nematoda: Anisakidae)s.

    PubMed

    Mattiucci, S; Paggi, L; Nascetti, G; Abollo, E; Webb, S C; Pascual, S; Cianchi, R; Bullini, L

    2001-01-01

    In order to assess the taxonomic status of Anisakis brevispiculata Dollfus, 1966 population samples of this taxon from central and south-eastern Atlantic ocean were compared at 22 enzymatic loci with samples belonging to Anisakis physeteris Baylis, 1923 from the Mediterranean sea and central-eastern Atlantic ocean. Very low interpopulational genetic divergence was observed both within A. brevispiculata (average D(Nei) = 0.008) and within A. physeteris (D(Nei) = 0.009) despite the geographic distance among the samples, indicating high levels of gene flow in both taxa. On the other hand, the average genetic distance between A. brevispiculata and A. physeteris was found to be D(Nei) = 0.80, a value generally observed between well differentiated congeneric species. The reproductive isolation between A. brevispiculata and A. physeteris is indicated by the following observations: (1) no F(1) hybrids or recombinant genotypes were until now observed; and (2) the two Anisakis species do not seem to share their definitive hosts. The main definitive host of A. brevispiculata is the pygmy sperm whale (Kogia breviceps), while for A. physeteris it is the sperm whale (Physeter catodon). Only adult males differ slightly in spicule length, while females and larval stages are not differentiated morphologically. Both A. brevispiculata and A.physeteris show a type II larva. The correct recognition of A. brevispiculata from A. physeteris and from other Anisakis species studied, in either sexes and at any life stage, is made easy by allozyme markers (e.g. Icdh, Gapdh, Sod-1, Np, Aat-2, Adk-2, fEst-2, PepB, PepC-2, Mpi). Diagnostic keys, which can be used for routine identification in the field of these Anisakis worms, based on genetic markers, are given.

  1. Spatial patterns of photosynthesis in thin- and thick-leaved epiphytic orchids: unravelling C3–CAM plasticity in an organ-compartmented way

    PubMed Central

    Rodrigues, Maria Aurineide; Matiz, Alejandra; Cruz, Aline Bertinatto; Matsumura, Aline Tiemi; Takahashi, Cassia Ayumi; Hamachi, Leonardo; Félix, Lucas Macedo; Pereira, Paula Natália; Latansio-Aidar, Sabrina Ribeiro; Aidar, Marcos Pereira Marinho; Demarco, Diego; Freschi, Luciano; Mercier, Helenice; Kerbauy, Gilberto Barbante

    2013-01-01

    Background and Aims A positive correlation between tissue thickness and crassulacean acid metabolism (CAM) expression has been frequently suggested. Therefore, this study addressed the question of whether water availability modulates photosynthetic plasticity in different organs of two epiphytic orchids with distinct leaf thickness. Methods Tissue morphology and photosynthetic mode (C3 and/or CAM) were examined in leaves, pseudobulbs and roots of a thick-leaved (Cattleya walkeriana) and a thin-leaved (Oncidium ‘Aloha’) epiphytic orchid. Morphological features were studied comparing the drought-induced physiological responses observed in each organ after 30 d of either drought or well-watered treatments. Key Results Cattleya walkeriana, which is considered a constitutive CAM orchid, displayed a clear drought-induced up-regulation of CAM in its thick leaves but not in its non-leaf organs (pseudobulbs and roots). The set of morphological traits of Cattleya leaves suggested the drought-inducible CAM up-regulation as a possible mechanism of increasing water-use efficiency and carbon economy. Conversely, although belonging to an orchid genus classically considered as performing C3 photosynthesis, Oncidium ‘Aloha’ under drought seemed to express facultative CAM in its roots and pseudobulbs but not in its leaves, indicating that such photosynthetic responses might compensate for the lack of capacity to perform CAM in its thin leaves. Morphological features of Oncidium leaves also indicated lower efficiency in preventing water and CO2 losses, while aerenchyma ducts connecting pseudobulbs and leaves suggested a compartmentalized mechanism of nighttime carboxylation via phosphoenolpyruvate carboxylase (PEPC) (pseudobulbs) and daytime carboxylation via Rubisco (leaves) in drought-exposed Oncidium plants. Conclusions Water availability modulated CAM expression in an organ-compartmented manner in both orchids studied. As distinct regions of the same orchid could perform

  2. Metabolic flux ratio analysis and multi-objective optimization revealed a globally conserved and coordinated metabolic response of E. coli to paraquat-induced oxidative stress.

    PubMed

    Shen, Tie; Rui, Bin; Zhou, Hong; Zhang, Ximing; Yi, Yin; Wen, Han; Zheng, Haoran; Wu, Jihui; Shi, Yunyu

    2013-01-27

    The ability of a microorganism to adapt to changes in the environment, such as in nutrient or oxygen availability, is essential for its competitive fitness and survival. The cellular objective and the strategy of the metabolic response to an extreme environment are therefore of tremendous interest and, thus, have been increasingly explored. However, the cellular objective of the complex regulatory structure of the metabolic changes has not yet been fully elucidated and more details regarding the quantitative behaviour of the metabolic flux redistribution are required to understand the systems-wide biological significance of this response. In this study, the intracellular metabolic flux ratios involved in the central carbon metabolism were determined by fractional (13)C-labeling and metabolic flux ratio analysis (MetaFoR) of the wild-type E. coli strain JM101 at an oxidative environment in a chemostat. We observed a significant increase in the flux through phosphoenolpyruvate carboxykinase (PEPCK), phosphoenolpyruvate carboxylase (PEPC), malic enzyme (MEZ) and serine hydroxymethyltransferase (SHMT). We applied an ε-constraint based multi-objective optimization to investigate the trade-off relationships between the biomass yield and the generation of reductive power using the in silico iJR904 genome-scale model of E. coli K-12. The theoretical metabolic redistribution supports that the trans-hydrogenase pathway should not play a direct role in the defence mounted by E. coli against oxidative stress. The agreement between the measured ratio and the theoretical redistribution established the significance of NADPH synthesis as the goal of the metabolic reprogramming that occurs in response to oxidative stress. Our work presents a framework that combines metabolic flux ratio analysis and multi-objective optimization to investigate the metabolic trade-offs that occur under varied environmental conditions. Our results led to the proposal that the metabolic response of E

  3. Impact of external pneumatic compression target inflation pressure on transcriptome-wide RNA expression in skeletal muscle.

    PubMed

    Martin, Jeffrey S; Kephart, Wesley C; Haun, Cody T; McCloskey, Anna E; Shake, Joshua J; Mobley, Christopher B; Goodlett, Michael D; Kavazis, Andreas; Pascoe, David D; Zhang, Lee; Roberts, Michael D

    2016-11-01

    Next-generation RNA sequencing was employed to determine the acute and subchronic impact of peristaltic pulse external pneumatic compression (PEPC) of different target inflation pressures on global gene expression in human vastus lateralis skeletal muscle biopsy samples. Eighteen (N = 18) male participants were randomly assigned to one of the three groups: (1) sham (n = 6), 2) EPC at 30-40 mmHg (LP-EPC; n = 6), and 3) EPC at 70-80 mmHg (MP-EPC; n = 6). One hour treatment with sham/EPC occurred for seven consecutive days. Vastus lateralis skeletal muscle biopsies were performed at baseline (before first treatment; PRE), 1 h following the first treatment (POST1), and 24 h following the last (7th) treatment (POST2). Changes from PRE in gene expression were analyzed via paired comparisons within each group. Genes were filtered to include only those that had an RPKM ≥ 1.0, a fold-change of ≥1.5 and a paired t-test value of <0.01. For the sham condition, two genes at POST1 and one gene at POST2 were significantly altered. For the LP-EPC condition, nine genes were up-regulated and 0 genes were down-regulated at POST1 while 39 genes were up-regulated and one gene down-regulated at POST2. For the MP-EPC condition, two genes were significantly up-regulated and 21 genes were down-regulated at POST1 and 0 genes were altered at POST2. Both LP-EPC and MP-EPC acutely alter skeletal muscle gene expression, though only LP-EPC appeared to affect gene expression with subchronic application. Moreover, the transcriptome response to EPC demonstrated marked heterogeneity (i.e., genes and directionality) with different target inflation pressures.

  4. Effect of plant age, larval age, and fertilizer treatment on resistance of a cry1Ab-transformed aromatic rice to lepidopterous stem borers and foliage feeders.

    PubMed

    Alinia, F; Ghareyazie, B; Rubia, L; Bennett, J; Cohen, M B

    2000-04-01

    The resistance of vegetative, booting, and flowering stage plants of a variety of an aromatic rice, Oryza sativa L., transformed with a Bacillus thuringiensis Berliner cry1Ab gene under control of the maize phosphoenolpyruvate carboxylase (PEPC) promoter was evaluated against four lepidopterous rice pests--the stem borers Chilo suppressalis (Walker) (Lepidoptera: Crambidae) and Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae), and the foliage feeders Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae) and Naranga aenescens Moore (Lepidoptera: Noctuidae). Plants of the cry1Ab-transformed line (no. 827) were more resistant to young larvae of S. incertulas, C. suppressalis, and C. medinalis than control plants at the vegetative stage but not at the flowering stage. Survival of 10-d-old stem borer larvae did not differ on cry1Ab plants and control plants at either the vegetative or flowering stage, but the development of 10-d-old C. suppressalis larvae was retarded on the vegetative stage cry1Ab plants. Immunological analysis also showed an apparent decline in Cry1Ab titer in leaf blades and leaf sheaths at the reproductive stage. In experiments comparing three fertilizer treatments (NPK, PK, and none), there was a significant interaction between fertilizer treatment and variety on larval survival only in whole-plant assays at booting stage with C. suppressalis. On cry1Ab plants, larval survival did not differ significantly among the three fertilizer levels, whereas on control plants survival was highest with the NPK treatment. cry1Ab plants tested at the sixth and seventh generations after transformation were more resistant than control plants to N. aenescens and C. suppressalis, respectively, suggesting that gene silencing will not occur in line 827. The results of the experiments are discussed in terms of resistance management for B. thuringiensis toxins in rice.

  5. Differential expression of genes involved in alternative glycolytic pathways, phosphorus scavenging and recycling in response to aluminum and phosphorus interactions in Citrus roots.

    PubMed

    Yang, Lin-Tong; Jiang, Huan-Xin; Qi, Yi-Ping; Chen, Li-Song

    2012-05-01

    The objective was to determine the possible links between the expression levels of genes involved in alternative glycolytic pathways, phosphorus (P) scavenging and recycling and Citrus tolerance to aluminum (Al) and/or P-deficiency. 'Xuegan' (Citrus sinensis) and 'Sour pummelo' (Citrus grandis) seedlings were irrigated for 18 weeks with nutrient solution containing 0 and 1.2 mM AlCl(3)·6H(2)O × 0, 50 and 200 μM KH(2)PO(4). C. sinensis displayed more tolerant to Al and P-deficiency than C. grandis. Under Al stress, C. sinensis accumulated more Al in roots and less Al in shoots than C. grandis. P concentration was higher in C. sinensis shoots and roots than in C. grandis ones. C. sinensis roots secreted more malate and citrate than C. grandis ones when exposed to Al. Al-induced-secretion of malate and citrate by excised roots from Al-treated seedlings decreased with increasing P supply. Al-induced-secretion of malate and citrate from roots and Al precipitation by P in roots might be responsible for Al-tolerance of C. sinensis. qRT-PCR analysis showed that Al-activated malate transporter (ALMT1), ATP-dependent phosphofructokinase (ATP-PFK), pyrophosphate-dependent phosphofructokinase (PPi-PFK), tonoplast adenosine-triphosphatase subunit A (V-ATPase A), tonoplast pyrophosphatase (V-PPiase), pyruvate kinase (PK), acid phosphatase (APase), phosphoenolpyruvate carboxylase (PEPC), malic enzyme (ME) and malate dehydrogenase (MDH) genes might contribute to the tolerance of Citrus to Al and/or P-deficiency, but any single gene could not explain the differences between the two species. Citrus tolerance to Al and/or P-deficiency might be caused by the coordinated regulation of gene expression involved in alternative glycolytic pathways, P scavenging and recycling.

  6. Spatial variation in photosynthetic CO(2) carbon and oxygen isotope discrimination along leaves of the monocot triticale (Triticum × Secale) relates to mesophyll conductance and the Péclet effect.

    PubMed

    Kodama, Naomi; Cousins, Asaph; Tu, Kevin P; Barbour, Margaret M

    2011-09-01

    Carbon and oxygen isotope discrimination of CO(2) during photosynthesis (Δ(13)C(obs) and Δ(18)O(obs)) were measured along a monocot leaf, triticale (Triticum × Secale). Both Δ(13)C(obs) and Δ(18)O(obs) increased towards the leaf tip. While this was expected for Δ(18)O(obs) , because of progressive enrichment of leaf water associated with the Péclet effect, the result was surprising for Δ(13) C(obs). To explore parameters determining this pattern, we measured activities of key photosynthetic enzymes [ribulose bis-phosphate carboxylase-oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEPC) and carbonic anhydrase) as well as maximum carboxylation and electron transport rates (V(cmax) and J(max)) along the leaf. Patterns in leaf internal anatomy along the leaf were also quantified. Mesophyll conductance (g(m)) is known to have a strong influence on Δ(13)C(obs) , so we used three commonly used estimation methods to quantify variation in g(m) along the leaf. Variation in Δ(13)C(obs) was correlated with g(m) and chloroplast surface area facing the intercellular air space, but unrelated to photosynthetic enzyme activity. The observed variation could cause errors at higher scales if the appropriate portion of a leaf is not chosen for leaf-level measurements and model parameterization. Our study shows that one-third of the way from the base of the leaf represents the most appropriate portion to enclose in the leaf chamber.

  7. Bicarbonate blocks iron translocation from cotyledons inducing iron stress responses in Citrus roots.

    PubMed

    Martínez-Cuenca, Mary-Rus; Legaz, Francisco; Forner-Giner, M Ángeles; Primo-Millo, Eduardo; Iglesias, Domingo J

    2013-07-01

    The effect of bicarbonate ion (HCO3(-)) on the mobilization of iron (Fe) reserves from cotyledons to roots during early growth of citrus seedlings and its influence on the components of the iron acquisition system were studied. Monoembryonic seeds of Citrus limon (L.) were germinated "in vitro" on two iron-deprived media, supplemented or not with 10mM HCO3(-) (-Fe+Bic and -Fe, respectively). After 21d of culture, Fe concentration in seedling organs was measured, as well as gene expression and enzymatic activities. Finally, the effect of Fe resupply on the above responses was tested in the presence and absence of HCO3(-) (+Fe+Bic or +Fe, respectively). -Fe+Bic seedlings exhibited lower Fe concentration in shoots and roots than -Fe ones but higher in cotyledons, associated to a significative inhibition of NRAMP3 expression. HCO3(-) upregulated Strategy I related genes (FRO1, FRO2, HA1 and IRT1) and FC-R and H(+)-ATPase activities in roots of Fe-starved seedlings. PEPC1 expression and PEPCase activity were also increased. When -Fe+Bic pre-treated seedlings were transferred to Fe-containing media for 15d, Fe content in shoots and roots increased, although to a lower extent in the +Fe+Bic medium. Consequently, the above-described root responses became markedly repressed, however, this effect was less pronounced in +Fe+Bic seedlings. In conclusion, it appears that HCO3(-) prevents Fe translocation from cotyledons to shoot and root, therefore reducing their Fe levels. This triggers Fe-stress responses in the root, enhancing the expression of genes related with Fe uptake and the corresponding enzymatic activities.

  8. Efficient and simple approach to in vitro culture of primary epithelial cancer cells

    PubMed Central

    Janik, Karolina; Popeda, Marta; Peciak, Joanna; Rosiak, Kamila; Smolarz, Maciej; Treda, Cezary; Rieske, Piotr; Stoczynska-Fidelus, Ewelina; Ksiazkiewicz, Magdalena

    2016-01-01

    Primary cancer cells constitute a favourable testing platform for in vitro research in oncology field as they reflect tumour state more accurately than the most commonly employed stable cell lines. Unfortunately, due to limited availability of material and difficulties with protocols validation, primary models are rarely implemented into laboratory practice. We have compared protocols for primary cultures, differing in media components and plate coatings. In terms of culture establishment, application of Geltrex® coating demonstrated equal efficiency to feeder layer (83% compared with 72% successfully established breast and 80% compared with 80% prostate tumour specimens), yet it was substantially less complicated and easier to validate. Both Geltrex® coating and tissue-specific primary cell medium were permanently required to successfully maintain primary epithelial prostate cancer cells (PEPCs) in culture. In case of primary epithelial breast cancer cells (PEBCs), collagen I coating enabled to obtain comparable number of passages to Geltrex® coating (P=0.438). Commercial primary cell media demonstrated lower efficiency than tissue-specific ones (PEPCs–5 compared with 8 and PEBCs–6 compared with 9 passages). Interestingly, both analysed tumour types were unsusceptible to induction of culture lifespan extension when transduced with SV40LT, BMI-1 or hEST2 genes, commonly applied as potential immortalizing agents. In conclusion, the approach based on extracellular matrix reconstitution and tissue-specific primary cell media is easy to validate and provides in vitro expansion sufficient for analytical purposes (approximately 8 passages). Therefore, it may facilitate implementation of hardly available experimental models for a variety of analyses. PMID:27803125

  9. New insights into the post-translational modification of multiple phosphoenolpyruvate carboxylase isoenzymes by phosphorylation and monoubiquitination during sorghum seed development and germination

    PubMed Central

    Ruiz-Ballesta, Isabel; Baena, Guillermo; Gandullo, Jacinto; Wang, Liqun; She, Yi-Min; Plaxton, William Charles; Echevarría, Cristina

    2016-01-01

    Phosphoenolpyruvate carboxylase (PEPC; E.C. 4.1.1.31) was characterized in developing and germinating sorghum seeds, focusing on the transcript and polypeptide abundance of multiple plant-type phosphoenolpyruvate carboxylase (PTPC) genes, and the post-translational modification of each isoenzyme by phosphorylation versus monoubiquitination during germination. We observed high levels of SbPPC4 (Sb07g014960) transcripts during early development (stage I), and extensive transcript abundance of SbPPC2 (Sb02g021090) and SbPPC3 (Sb04g008720) throughout the entire life cycle of the seed. Although tandem mass spectrometry (MS) analysis of immunopurified PTPC indicated that four different PTPC isoenzymes were expressed in the developing and germinating seeds, SbPPC3 was the most abundant isozyme of the developing seed, and of the embryo and the aleurone layer of germinating seeds. In vivo phosphorylation of the different PTPC isoenzymes at their conserved N-terminal seryl phosphorylation site during germination was also established by MS/MS analysis. Furthermore, three of the four isoenzymes were partially monoubiquitinated, with MS/MS pinpointing SbPPC2 and SbPPC3 monoubiquitination at the conserved Lys-630 and Lys-624 residues, respectively. Our results demonstrate that monoubiquitination and phosphorylation simultaneously occur in vivo with different PTPC isozymes during seed germination. In addition, we show that PTPC monoubiquitination in germinating sorghum seeds always increases at stage II (emergence of the radicle), is maintained during the aerobic period of rapid cell division and reserve mobilization, and remains relatively constant until stage IV–V when coleoptiles initiate the formation of the photosynthetic tissues. PMID:27194739

  10. Positive selection of Kranz and non-Kranz C4 phosphoenolpyruvate carboxylase amino acids in Suaedoideae (Chenopodiaceae).

    PubMed

    Rosnow, Josh J; Edwards, Gerald E; Roalson, Eric H

    2014-07-01

    In subfamily Suaedoideae, four independent gains of C4 photosynthesis are proposed, which includes two parallel origins of Kranz anatomy (sections Salsina and Schoberia) and two independent origins of single-cell C4 anatomy (Bienertia and Suaeda aralocaspica). Additional phylogenetic support for this hypothesis was generated from sequence data of the C-terminal portion of the phosphoenolpyruvate carboxylase (PEPC) gene used in C4 photosynthesis (ppc-1) in combination with previous sequence data. ppc-1 sequence was generated for 20 species in Suaedoideae and two outgroup Salsola species that included all types of C4 anatomies as well as two types of C3 anatomies. A branch-site test for positively selected codons was performed using the software package PAML. From labelling of the four branches where C4 is hypothesized to have developed (foreground branches), residue 733 (maize numbering) was identified to be under positive selection with a posterior probability >0.99 and residue 868 at the >0.95 interval using Bayes empirical Bayes (BEB). When labelling all the branches within C4 clades, the branch-site test identified 13 codons to be under selection with a posterior probability >0.95 by BEB; this is discussed considering current information on functional residues. The signature C4 substitution of an alanine for a serine at position 780 in the C-terminal end (which is considered a major determinant of affinity for PEP) was only found in four of the C4 species sampled, while eight of the C4 species and all the C3 species have an alanine residue; indicating that this substitution is not a requirement for C4 function.

  11. Elevated CO2 concentration around alfalfa nodules increases N2 fixation.

    PubMed

    Fischinger, Stephanie A; Hristozkova, Marieta; Mainassara, Zaman-Allah; Schulze, Joachim

    2010-01-01

    Nodule CO2 fixation via PEPC provides malate for bacteroids and oxaloacetate for N assimilation. The process is therefore of central importance for efficient nitrogen fixation. Nodule CO2 fixation is known to depend on external CO2 concentration. The hypothesis of the present paper was that nitrogen fixation in alfalfa plants is enhanced when the nodules are exposed to elevated CO2 concentrations. Therefore nodulated plants of alfalfa were grown in a hydroponic system that allowed separate aeration of the root/nodule compartment that avoided any gas leakage to the shoots. The root/nodule compartments were aerated either with a 2500 microl l(-1) (+CO2) or zero microl l(-1) (-CO2) CO2-containing N2/O2 gas flow (80/20, v/v). Nodule CO2 fixation, nitrogen fixation, and growth were strongly increased in the +CO2 treatment in a 3-week experimental period. More intensive CO2 and nitrogen fixation coincided with higher per plant amounts of amino acids and organic acids in the nodules. Moreover, the concentration of asparagine was increased in both the nodules and the xylem sap. Plants in the +CO2 treatment tended to develop nodules with higher %N concentration and individual activity. In a parallel experiment on plants with inefficient nodules (fix-) the +CO2 treatment remained without effect. Our data support the thesis that nodule CO2 fixation is pivotal for efficient nitrogen fixation. It is concluded that strategies which enhance nodule CO2 fixation will improve nitrogen fixation and nodule formation. Moreover, sufficient CO2 application to roots and nodules is necessary for growth and efficient nitrogen fixation in hydroponic and aeroponic growth systems.

  12. Phylogenetic Insights into Chinese Rubus (Rosaceae) from Multiple Chloroplast and Nuclear DNAs

    PubMed Central

    Wang, Yan; Chen, Qing; Chen, Tao; Tang, Haoru; Liu, Lin; Wang, Xiaorong

    2016-01-01

    Rubus L. is a large and taxonomically complex genus, species of which exhibit apomixis, polyploidy, and frequent hybridization. Most of Chinese Rubus are assigned in two major sections, Idaeobatus and Malachobatus. To explore the phylogenetic relationships within Chinese Rubus, inferences upon three chloroplast DNA (rbcL, rpl20-rps12, and trnG-trnS), nuclear ribosomal ITS, and two low-copy nuclear markers (GBSSI-2 and PEPC) were deduced in 142 Rubus taxa from 17 subsections in 6 sections. nrITS and GBSSI-2 were the most informative among the six DNA regions assessed. Phylogenetic relationships within Rubus were well-resolved by combined nuclear datasets rather than chloroplast markers. The phylogenetic inferences strongly supported that section Idaeobatus was a polyphyletic group with four distant clades. All samples of sect. Malachobatus formed a monophyletic clade, in which R. tsangorum and R. amphidasys of sect. Dalibardastrum, and R. peltatus from subsection Peltati of sect. Idaeobatus were always nested. Rubus pentagonus (2n = 2x = 14) from subsect. Alpestres of sect. Idaeobatus was a sister group to the polyploid sect. Malachobatus, as well as the polytomy of three sect. Cyalctis members. This suggests that some polyploids of Malachobatus might originate from common ancestors, via polyploidization of hybrids between R. pentagonus and sect. Cylactis species. They had experienced species explosion in a short time. Section Dalibardastrum species have potential parental lineages from subsects. Moluccani and Stipulosi of sect. Malachobatus. Based on molecular phylogenies, we also provided recommendations for the taxonomic treatments of four taxa. In addition, our results showed certain incongruence between chloroplast and nuclear markers, which might be due to hybridization and introgression. PMID:27446191

  13. Genotypic variability within Tunisian grapevine varieties (Vitis vinifera L.) facing bicarbonate-induced iron deficiency.

    PubMed

    Ksouri, Riadh; Debez, Ahmed; Mahmoudi, Henda; Ouerghi, Zeineb; Gharsalli, Mohamed; Lachaâl, Mokhtar

    2007-05-01

    Morpho-physiological responses to bicarbonate-induced Fe deficiency were investigated in five Vitis vinifera L. Tunisian varieties (Khamri, Blanc3, Arich Dressé, Beldi, and Balta4). One-month-old woody cuttings were cultivated for 85days on a free calcareous soil irrigated with tap water containing increasing bicarbonate levels (0, 4, 8, 12, and 16mM NaHCO(3)). After this screening, a second experiment compared root biochemical responses of two contrasting genotypes (tolerant-sensitive) dealing with bicarbonate-induced iron deprivation (20microM Fe+/-10mM HCO(3)(-)) for 75days. Using morpho-physiological criteria, grapevine tolerance to HCO(3)(-)-induced Fe shortage appeared to be genotype-dependent: Balta4 and Beldi varieties showed the highest leaf-chlorosis score (especially at the extreme HCO(3)(-) levels), in contrast to Khamri variety. Growth parameters (shoot height, total leaf area, leaf number, and biomass production) as well as juvenile leaf chlorophyll content were also differently affected depending on both genotype and bicarbonate dose. At 16mM HCO(3)(-), Khamri was the less sensitive variety, contrasting with Balta4. On the other hand, chlorophyll content correlated positively with HCl-extractible Fe content of the juvenile leaves, suggesting that the grapevine response to iron deficiency may partly depend on to the plant ability to adequately supply young leaves with this element. Root biochemical responses revealed a relatively higher root acidification capacity in Khamri (tolerant) under Fe-deficiency while no significant changes occurred in Balta4 (sensitive). In addition, Fe(III)-reductase and phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) activities were strongly stimulated by Fe-deficiency in Khamri, while remaining constant in Balta4. These findings suggest that biochemical parameters may constitute reliable criteria for the selection of tolerant grapevine genotypes to iron chlorosis.

  14. Evolution in African tropical trees displaying ploidy-habitat association: The genus Afzelia (Leguminosae).

    PubMed

    Donkpegan, Armel S L; Doucet, Jean-Louis; Migliore, Jérémy; Duminil, Jérôme; Dainou, Kasso; Piñeiro, Rosalía; Wieringa, Jan J; Champluvier, Dominique; Hardy, Olivier J

    2017-02-01

    Polyploidy has rarely been documented in rain forest trees but it has recently been found in African species of the genus Afzelia (Leguminosae), which is composed of four tetraploid rain forest species and two diploid dry forest species. The genus Afzelia thus provides an opportunity to examine how and when polyploidy and habitat shift occurred in Africa, and whether they are associated. In this study, we combined three plastid markers (psbA, trnL, ndhF), two nuclear markers (ribosomal ITS and the single-copy PEPC E7 gene), plastomes (obtained by High Throughput Sequencing) and morphological traits, with an extensive taxonomic and geographic sampling to explore the evolutionary history of Afzelia. Both nuclear DNA and morphological vegetative characters separated diploid from tetraploid lineages. Although the two African diploid species were well differentiated genetically and morphologically, the relationships among the tetraploid species were not resolved. In contrast to the nuclear markers, plastid markers revealed that one of the diploid species forms a well-supported clade with the tetraploids, suggesting historical hybridisation, possibly in relation with genome duplication (polyploidization) and habitat shift from dry to rain forests. Molecular dating based on fossil-anchored gene phylogenies indicates that extant Afzelia started diverging c. 14.5 or 20Ma while extant tetraploid species started diverging c. 7.0 or 9.4Ma according to plastid and nuclear DNA, respectively. Additional studies of tropical polyploid plants are needed to assess whether the ploidy-habitat association observed in African Afzelia would reflect a role of polyploidization in niche divergence in the tropics.

  15. The efficiency of nitrogen fixation of the model legume Medicago truncatula (Jemalong A17) is low compared to Medicago sativa.

    PubMed

    Sulieman, Saad; Schulze, Joachim

    2010-06-15

    Medicago truncatula (Gaertn.) (barrel medic) serves as a model legume in plant biology. Numerous studies have addressed molecular aspects of the biology of M. truncatula, while comparatively little is known about the efficiency of N(2) fixation at the whole plant level. The objective of the present study was to compare the efficiency of N(2) fixation of M. truncatula to the genetically closely related Medicago sativa (L.) (alfalfa). The relative growth of both species relying exclusively on N(2) fixation versus nitrate nutrition, H(2) evolution, nitrogen assimilation, the concentration of amino acids and organic acids in nodules, and (15)N(2) uptake and distribution were studied. M. truncatula showed much lower efficiency of N(2) fixation. Nodule-specific activity was several-fold lower when compared to M. sativa, partially as a result of a lower electron allocation to N(2) versus H(+). M. truncatula or M. sativa plants grown solely on N(2) fixation as a nitrogen source reached about 30% or 80% of growth, respectively, when compared to plants supplied with sufficient nitrate. Moreover, M. truncatula had low %N in shoots and a lower allocation of (15)N to shoots during 1h (15)N(2) labeling period. Amino acid concentration was about 20% higher in M. sativa nodules, largely as a result of more asparagine, while the organic acid concentration was about double in M. sativa, coinciding with a six-fold higher concentration of malate. Total soluble protein in nodules was about three times lower in M. truncatula and the pattern of enzyme activity in that fraction was strongly different. Sucrose cleaving enzymes displayed higher activity in M. truncatula nodules, while the activity of phosphoenolpyruvate carboxylase (PEPC) was much lower. It is concluded that the low efficiency of the M. truncatula symbiotic system is related to a low capacity of organic acid formation and limited nitrogen export from nodules.

  16. Mesophyll Chloroplast Investment in C3, C4 and C2 Species of the Genus Flaveria.

    PubMed

    Stata, Matt; Sage, Tammy L; Hoffmann, Natalie; Covshoff, Sarah; Ka-Shu Wong, Gane; Sage, Rowan F

    2016-05-01

    The mesophyll (M) cells of C4 plants contain fewer chloroplasts than observed in related C3 plants; however, it is uncertain where along the evolutionary transition from C3 to C4 that the reduction in M chloroplast number occurs. Using 18 species in the genus Flaveria, which contains C3, C4 and a range of C3-C4 intermediate species, we examined changes in chloroplast number and size per M cell, and positioning of chloroplasts relative to the M cell periphery. Chloroplast number and coverage of the M cell periphery declined in proportion to increasing strength of C4 metabolism in Flaveria, while chloroplast size increased with increasing C4 cycle strength. These changes increase cytosolic exposure to the cell periphery which could enhance diffusion of inorganic carbon to phosphenolpyruvate carboxylase (PEPC), a cytosolic enzyme. Analysis of the transcriptome from juvenile leaves of nine Flaveria species showed that the transcript abundance of four genes involved in plastid biogenesis-FtsZ1, FtsZ2, DRP5B and PARC6-was negatively correlated with variation in C4 cycle strength and positively correlated with M chloroplast number per planar cell area. Chloroplast size was negatively correlated with abundance of FtsZ1, FtsZ2 and PARC6 transcripts. These results indicate that natural selection targeted the proteins of the contractile ring assembly to effect the reduction in chloroplast numbers in the M cells of C4 Flaveria species. If so, efforts to engineer the C4 pathway into C3 plants might evaluate whether inducing transcriptome changes similar to those observed in Flaveria could reduce M chloroplast numbers, and thus introduce a trait that appears essential for efficient C4 function.

  17. Phylogeny and biogeography of Tynanthus Miers (Bignonieae, Bignoniaceae).

    PubMed

    M P de Medeiros, Maria Cláudia; Lohmann, Lúcia G

    2015-04-01

    The origin of Neotropical biodiversity represents a key question in evolutionary biology. Despite the attempts to decipher the role of ecological and historical factors to present-day distribution patterns, robust phylogenetic studies of Neotropical clades are still needed before a comprehensive picture of the origin of Neotropical biodiversity can be achieved. Tynanthus Miers (Bignonieae, Bignoniaceae) is a well-circumscribed genus of Neotropical lianas with species that are narrowly distributed, except from a few taxa. The genus is characterized by a clove odor, small bilabiate flowers with the two upper lobes almost fused, and fruits with raised margins, all of which represent morphological synapomorphies for this clade. Other distinctive characters are the thecae reflexed forward, the densely pubescent ovaries and the poorly-developed nectariferous disk. The circumscription of the genus has remained constant over the years, despite the problematic limits of most genera of tribe Bignonieae. In this study, we reconstruct the phylogeny of Tynanthus based on two plastid (ndhF and rpl32-trnL) and one nuclear (pepC) markers and use this phylogenetic framework to investigate the biogeographical history of the genus. Our phylogenetic hypothesis provides further support for the monophyly of Tynanthus, and strongly supports a series of infra-generic clades. Most species are reconstructed as monophyletic, while T. cognatus and T. polyanthus are paraphyletic. Biogeographic reconstructions suggest that Tynanthus originated between 9.4 and 21.5Mya, most likely at approximately 15.3Mya. The MRCA of the genus was likely broadly distributed through lowland Amazonia, Western South America and Central America and diversified in the Neotropics during the Miocene. Closely related species are generally distributed within the same biogeographic area, suggesting that niche conservatism has played an important role in the diversification history of the group.

  18. Association of class 1 and 2 integrons with multidrug-resistant Acinetobacter baumannii international clones and Acinetobacter nosocomialis isolates.

    PubMed

    Martins, Natacha; Picão, Renata Cristina; Adams-Sapper, Sheila; Riley, Lee W; Moreira, Beatriz Meurer

    2015-01-01

    The Acinetobacter baumannii clonal complex 113/79 (CC113/79) and class 2 integrons predominate in Latin America; a relationship between these characteristics was explored. The presence of integrases was determined in successive hospital Acinetobacter isolates (163 A. baumannii isolates and 72 Acinetobacter nosocomialis isolates). Most isolates had integrons, but class 1 and 2 integrons were present significantly more often in CC109/1 and CC113/79, respectively. The high prevalence of CC113/79 in Latin America may account for the predominance of class 2 integrons.

  19. 49 CFR 176.220 - Smoking or open flame and posting of warning signs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Smoking or open flame and posting of warning signs... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.220 Smoking or open flame and posting of warning signs. (a) Smoking or the use of open flame is prohibited in any hold...

  20. 49 CFR 176.220 - Smoking or open flame and posting of warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Smoking or open flame and posting of warning signs... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.220 Smoking or open flame and posting of warning signs. (a) Smoking or the use of open flame is prohibited in any hold...

  1. 49 CFR 176.220 - Smoking or open flame and posting of warning signs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Smoking or open flame and posting of warning signs... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.220 Smoking or open flame and posting of warning signs. (a) Smoking or the use of open flame is prohibited in any hold...

  2. 49 CFR 176.220 - Smoking or open flame and posting of warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Smoking or open flame and posting of warning signs... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.220 Smoking or open flame and posting of warning signs. (a) Smoking or the use of open flame is prohibited in any hold...

  3. 49 CFR 176.220 - Smoking or open flame and posting of warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Smoking or open flame and posting of warning signs... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.220 Smoking or open flame and posting of warning signs. (a) Smoking or the use of open flame is prohibited in any hold...

  4. 49 CFR 213.63 - Track surface.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... less than 62 feet apart may not be more than* 1,2 3 21/4 2 13/4 11/2 * Where determined by engineering....) 2 However, to control harmonics on Class 2 through 5 jointed track with staggered joints,...

  5. 49 CFR 173.5 - Agricultural operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS General § 173.5 Agricultural operations. (a) For other than a Class 2 material,...

  6. 49 CFR 173.5 - Agricultural operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS General § 173.5 Agricultural operations. (a) For other than a Class 2 material,...

  7. 49 CFR 173.5 - Agricultural operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS General § 173.5 Agricultural operations. (a) For other than a Class 2 material,...

  8. Attention Deficit Disorder in College: Faculty and Students. Partners in Education.

    ERIC Educational Resources Information Center

    Latham, Patricia H.; Latham, Peter S.

    This publication provides an overview of attention deficit disorders (ADD) and the legal rights of college students with ADD. Possible accommodations that schools can make for students with ADD are provided and include: (1) provide structure and reduce distraction in class; (2) simplify and repeat instructions, as necessary, both orally and in…

  9. Using Simulation to Involve Students: Instructor's Guide and Participant's Manual. Teaching Procedures for the New Social Studies.

    ERIC Educational Resources Information Center

    Kurfman, Dana G.; Phillips, Ina M.

    Using simulations developed by the High School Geography Project and films recording the use of the simulations, teachers learn to: (1) use simulation exercises in class; (2) provide a classroom atmosphere conducive to free interaction and expression among students; (3) analyze simulation in terms of problems considered, alternative choices,…

  10. 49 CFR 176.92 - Cylinders laden in vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which is... 49 Transportation 2 2014-10-01 2014-10-01 false Cylinders laden in vehicles. 176.92 Section...

  11. 49 CFR 176.92 - Cylinders laden in vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which is... 49 Transportation 2 2012-10-01 2012-10-01 false Cylinders laden in vehicles. 176.92 Section...

  12. 49 CFR 176.92 - Cylinders laden in vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which is... 49 Transportation 2 2011-10-01 2011-10-01 false Cylinders laden in vehicles. 176.92 Section...

  13. 49 CFR 176.92 - Cylinders laden in vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which is... 49 Transportation 2 2013-10-01 2013-10-01 false Cylinders laden in vehicles. 176.92 Section...

  14. 49 CFR 176.92 - Cylinders laden in vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.92 Cylinders laden in vehicles. Any cylinder of Class 2 (compressed gas) material which is... 49 Transportation 2 2010-10-01 2010-10-01 false Cylinders laden in vehicles. 176.92 Section...

  15. Survey of the Nutrition Knowledge Of Practicing Male and Female Physical Educator/Coaches.

    ERIC Educational Resources Information Center

    Webb, James L.; And Others

    An assessment was made of the extent of nutrition knowledge of physical education teachers and coaches. The investigation addressed three primary questions: (1) Do practicing physical educator/coaches possess nutritional knowledge comparable to that of college students enrolled in a university basic nutrition class?; (2) Do male and female…

  16. 49 CFR 174.290 - Materials extremely poisonous by inhalation shipped by, for, or to the Department of Defense.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases... specification metal drums, by boxcar, gondola car (flat bottom), or stock car in carload lots. See §§ 174.55 and... and 179.301 of this subchapter), mounted on or secured to a multi-unit car or gondola car (flat...

  17. 49 CFR 174.290 - Materials extremely poisonous by inhalation shipped by, for, or to the Department of Defense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases... specification metal drums, by boxcar, gondola car (flat bottom), or stock car in carload lots. See §§ 174.55 and... and 179.301 of this subchapter), mounted on or secured to a multi-unit car or gondola car (flat...

  18. 49 CFR 176.230 - Stowage of Division 2.1 (flammable gas) materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Stowage of Division 2.1 (flammable gas) materials... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.230 Stowage of Division 2.1 (flammable gas) materials. Division 2.1 (flammable gas) materials transported in...

  19. 49 CFR 174.290 - Materials extremely poisonous by inhalation shipped by, for, or to the Department of Defense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases... specification metal drums, by boxcar, gondola car (flat bottom), or stock car in carload lots. See §§ 174.55 and... and 179.301 of this subchapter), mounted on or secured to a multi-unit car or gondola car (flat...

  20. 49 CFR 174.290 - Materials extremely poisonous by inhalation shipped by, for, or to the Department of Defense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases... specification metal drums, by boxcar, gondola car (flat bottom), or stock car in carload lots. See §§ 174.55 and... and 179.301 of this subchapter), mounted on or secured to a multi-unit car or gondola car (flat...

  1. 49 CFR 174.200 - Special handling requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Detailed Requirements for Class 2 (Gases) Materials § 174.200 Special handling requirements. (a) Division 2.1 (flammable gas) materials may not be loaded, transported, or stored in a rail car equipped with any type of lighted heater or open-flame device, or in a rail car equipped with any apparatus...

  2. 49 CFR 176.230 - Stowage of Division 2.1 (flammable gas) materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Stowage of Division 2.1 (flammable gas) materials... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.230 Stowage of Division 2.1 (flammable gas) materials. Division 2.1 (flammable gas) materials transported in...

  3. 49 CFR 174.290 - Materials extremely poisonous by inhalation shipped by, for, or to the Department of Defense.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY RAIL Detailed Requirements for Class 2 (Gases... specification metal drums, by boxcar, gondola car (flat bottom), or stock car in carload lots. See §§ 174.55 and... and 179.301 of this subchapter), mounted on or secured to a multi-unit car or gondola car (flat...

  4. 49 CFR 176.230 - Stowage of Division 2.1 (flammable gas) materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Stowage of Division 2.1 (flammable gas) materials... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.230 Stowage of Division 2.1 (flammable gas) materials. Division 2.1 (flammable gas) materials transported in...

  5. 49 CFR 179.101-1 - Individual specification requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120... thickness of plates shall be not less than 1/2 inch. 4 Tank cars not equipped with a thermal protection or an insulation system used for the transportation of a Class 2 (compressed gas) material must have...

  6. 49 CFR 176.230 - Stowage of Division 2.1 (flammable gas) materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Stowage of Division 2.1 (flammable gas) materials... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.230 Stowage of Division 2.1 (flammable gas) materials. Division 2.1 (flammable gas) materials transported in...

  7. 49 CFR 176.230 - Stowage of Division 2.1 (flammable gas) materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Stowage of Division 2.1 (flammable gas) materials... CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed Gas) Materials § 176.230 Stowage of Division 2.1 (flammable gas) materials. Division 2.1 (flammable gas) materials transported in...

  8. 77 FR 25375 - United States Standards for Wheat

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ...-AB12 United States Standards for Wheat Correction PART 810 In proposed rule document 2012-9182... 4.0 8.0 12.0 20.0 Total \\1\\ 3.0 5.0 8.0 12.0 20.0 Wheat of other classes: \\2\\ Contrasting classes...

  9. 77 FR 19412 - Petition for Waiver of Compliance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... blocks of 10 cars, while up to 20 inbound empties could be moved as they arrive (without unnecessary... inbound empties at the Elk City bottleneck between Class 2 and excepted track, where longer strings must..., Farmrail states that a rail shipper in Sayre receives inbound loaded tank cars of methanol at a rate...

  10. 49 CFR 192.611 - Change in class location: Confirmation or revision of maximum allowable operating pressure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of maximum allowable operating pressure. (a) If the hoop stress corresponding to the established... locations. The corresponding hoop stress may not exceed 72 percent of the SMYS of the pipe in Class 2... pressure per § 192.620, the corresponding hoop stress may not exceed 80 percent of the SMYS of the pipe...

  11. 27 CFR 5.22 - The standards of identity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... materials, as to be without distinctive character, aroma, taste, or color. (2) “Grain spirits” are neutral spirits distilled from a fermented mash of grain and stored in oak containers. (b) Class 2; whisky... includes mixtures of such whisky. (iii) Whiskies conforming to the standards prescribed in paragraphs...

  12. 27 CFR 5.22 - The standards of identity.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... materials, as to be without distinctive character, aroma, taste, or color. (2) “Grain spirits” are neutral spirits distilled from a fermented mash of grain and stored in oak containers. (b) Class 2; whisky... includes mixtures of such whisky. (iii) Whiskies conforming to the standards prescribed in paragraphs...

  13. 27 CFR 5.22 - The standards of identity.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... materials, as to be without distinctive character, aroma, taste, or color. (2) “Grain spirits” are neutral spirits distilled from a fermented mash of grain and stored in oak containers. (b) Class 2; whisky... includes mixtures of such whisky. (iii) Whiskies conforming to the standards prescribed in paragraphs...

  14. 27 CFR 5.22 - The standards of identity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... materials, as to be without distinctive character, aroma, taste, or color. (2) “Grain spirits” are neutral spirits distilled from a fermented mash of grain and stored in oak containers. (b) Class 2; whisky... includes mixtures of such whisky. (iii) Whiskies conforming to the standards prescribed in paragraphs...

  15. 27 CFR 5.22 - The standards of identity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... materials, as to be without distinctive character, aroma, taste, or color. (2) “Grain spirits” are neutral spirits distilled from a fermented mash of grain and stored in oak containers. (b) Class 2; whisky... includes mixtures of such whisky. (iii) Whiskies conforming to the standards prescribed in paragraphs...

  16. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...—Surrogate Parameters for Direct Dischargers Regulated parameters Treatability class Amyl alcohol Alcohols... Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters in the same treatability class. 2 Surrogates have not been identified for the “Miscellaneous” treatability class. Table...

  17. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Table 1—Surrogate Parameters for Direct Dischargers Regulated parameters Treatability class Amyl alcohol... Cellosolve Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters in the same treatability class. 2 Surrogates have not been identified for the...

  18. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...—Surrogate Parameters for Direct Dischargers Regulated parameters Treatability class Amyl alcohol Alcohols... Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters in the same treatability class. 2 Surrogates have not been identified for the “Miscellaneous” treatability class. Table...

  19. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Table 1—Surrogate Parameters for Direct Dischargers Regulated parameters Treatability class Amyl alcohol... Cellosolve Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters in the same treatability class. 2 Surrogates have not been identified for the...

  20. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Table 1—Surrogate Parameters for Direct Dischargers Regulated parameters Treatability class Amyl alcohol... Cellosolve Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters in the same treatability class. 2 Surrogates have not been identified for the...

  1. [The validation of the maximum permissible concentration of pyromellitic dianhydride in the atmosphere].

    PubMed

    Sokolov, S M; Filonov, V P; Amvros'ev, P A; Drobenia, V V

    1997-01-01

    The maximum allowable concentration (MAC) of pyromellitic acid dianhydride (PMAD) in the ambient air was substabtiated by physiological, hematological, and physiological methods. The inhalation of this substance by animals reduced their body weight, erythrocytic osmotic resistance, enhanced animals' sensitization. The mean daily MAC of PMAD was found to be 0.01 mg/m3. PMAD was considered to be Hazard Class 2.

  2. Big Business Invests in Catholic Education.

    ERIC Educational Resources Information Center

    Rivera, Richard

    2003-01-01

    Recognizes the unused potential of inner city kids and describes how The Institute for Leadership, Excellence and Academic Development (I-Lead) program has helped prepare these students for admittance to universities and colleges. I-Lead offers four core courses: (1) test prep class; (2) constitutional law class; (3) writing class; and (4)…

  3. Making Sense of Time as Context: Theoretical Affordances of Chronotopes in the Study of Schooling and Student Success. WCER Working Paper No. 2010-11

    ERIC Educational Resources Information Center

    Compton-Lilly, Catherine

    2010-01-01

    Time regulates the lives of educators. Time on task, 45-minute classes, 2-hour literacy blocks, 10-week marking periods, and 40-week school years are central to teachers' lives and to the operation of schools. In contemporary schools, benchmarks, standards, promotion, retention, graduation, and ultimately school success are all intricately…

  4. Effect of welding conditions on transformation and properties of heat-affected zones in LWR (light-water reactor) vessel steels

    SciTech Connect

    Lundin, C.D.; Mohammed, S. . Welding Research and Engineering)

    1990-11-01

    The continuous cooling transformation behavior (CCT) and isothermal transformation (IT) behavior were determined for SA-508 and SA-533 materials for conditions pertaining to standard heat treatment and for the coarse-grained region of the heat-affected zone (HAZ). The resulting diagrams help to select welding conditions that produce the most favorable microconstituent for the development of optimum postweld heat treatment (PWHT) toughness levels. In the case of SA-508 and SA-533, martensite responds more favorably to PWHT than does bainite. Bainite is to be avoided for the optimum toughness characteristics of the HAZ. The reheat cracking tendency for both steels was evaluated by metallographic studies of simulated HAZ structures subjected to PWHT cycles and simultaneous restraint. Both SA-533, Grade B, Class 1, and SA-508, Class 2, cracked intergranularly. The stress rupture parameter (the product of the stress for a rupture life of 10 min and the corresponding reduction of area) calculated for both steels showed that SA-508, Class 2, was more susceptible to reheat cracking than SA-533, Grade B, Class 1. Cold cracking tests (Battelle Test and University of Tennessee modified hydrogen susceptibility test) indicated that a higher preheat temperature is required for SA-508, Class 2, to avoid cracking than is required for SA-533, Grade B, Class 1. Further, the Hydrogen Susceptibility Test showed that SA-508, Class 2, is more susceptible to hydrogen embrittlement than is SA-533, Grade B, Class 1.

  5. 27 CFR 5.35 - Class and type.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of whiskies in mixtures. In the case of any of the types of whisky defined in § 5.22(b), Class 2, which contains any whisky or whiskies produced in a country other than that indicated by the type designation, there shall be stated on the brand label the percentage of such whisky and the country or...

  6. 27 CFR 5.35 - Class and type.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of whiskies in mixtures. In the case of any of the types of whisky defined in § 5.22(b), Class 2, which contains any whisky or whiskies produced in a country other than that indicated by the type designation, there shall be stated on the brand label the percentage of such whisky and the country or...

  7. 27 CFR 5.35 - Class and type.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of whiskies in mixtures. In the case of any of the types of whisky defined in § 5.22(b), Class 2, which contains any whisky or whiskies produced in a country other than that indicated by the type designation, there shall be stated on the brand label the percentage of such whisky and the country or...

  8. 27 CFR 5.35 - Class and type.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of whiskies in mixtures. In the case of any of the types of whisky defined in § 5.22(b), Class 2, which contains any whisky or whiskies produced in a country other than that indicated by the type designation, there shall be stated on the brand label the percentage of such whisky and the country or...

  9. Social Class and Ethnic Differences in College Students' Career Maturity: A Quantitative and Qualitative Analysis.

    ERIC Educational Resources Information Center

    Luzzo, Darrell Anthony

    Social class and ethnic group differences in college students' career maturity were investigated. Participants were 401 undergraduates (250 females, 151 males) attending California State Univesity, Long Beach. Quantitative measurements included: (1) the Duncan Index of social class; (2) Career Maturity Inventory-Attitude Scale; (3) the Vocational…

  10. Defense Transportation: DOD Needs to Take Actions to Improve the Transportation of Hazardous Material Shipments

    DTIC Science & Technology

    2014-05-01

    report of a bottled oxygen (nonflammable gas, class 2.2 HAZMAT) shipment that arrived via highway improperly packaged for air shipment. According to the...Waste, and Abuse in Federal Programs Congressional Relations Public Affairs Please Print on Recycled Paper.

  11. 49 CFR 192.903 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater... under paragraph (1)(iii) of this definition or paragraph (2)(i) of this definition, the radius of the... of an area with a radius of 660 feet (200 meters) to the area of the potential impact circle...

  12. Gender Fictions.

    ERIC Educational Resources Information Center

    Lee, Lesley

    1992-01-01

    Reviews and compares "Gender and Mathematics" edited by Leone Burton and Valerie Walkerdine's book "Schoolgirl Fictions" on proposed truths related to gender issues in mathematics. Issues include (1) attention given to boys and girls in mathematics class; (2) the effects of noncompetitive classroom environments; and (3) sex differences in…

  13. 49 CFR 176.225 - Stowage of chlorine.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Stowage of chlorine. 176.225 Section 176.225 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Requirements for Class 2 (Compressed Gas) Materials § 176.225 Stowage of chlorine. Chlorine (UN 1017) must...

  14. 49 CFR 176.225 - Stowage of chlorine.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Stowage of chlorine. 176.225 Section 176.225 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Requirements for Class 2 (Compressed Gas) Materials § 176.225 Stowage of chlorine. Chlorine (UN 1017) must...

  15. 49 CFR 176.225 - Stowage of chlorine.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Stowage of chlorine. 176.225 Section 176.225 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Requirements for Class 2 (Compressed Gas) Materials § 176.225 Stowage of chlorine. Chlorine (UN 1017) must...

  16. 49 CFR 176.225 - Stowage of chlorine.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Stowage of chlorine. 176.225 Section 176.225 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Requirements for Class 2 (Compressed Gas) Materials § 176.225 Stowage of chlorine. Chlorine (UN 1017) must...

  17. 49 CFR 176.225 - Stowage of chlorine.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Stowage of chlorine. 176.225 Section 176.225 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Requirements for Class 2 (Compressed Gas) Materials § 176.225 Stowage of chlorine. Chlorine (UN 1017) must...

  18. 49 CFR 213.109 - Crossties.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.109 Crossties. (a) Crossties shall be made of a material to which rail can be securely fastened. (b) Each 39 foot segment of track shall have— (1) A...) Each 39 foot segment of: Class 1 track shall have five crossties; Classes 2 and 3 track shall...

  19. Assisting the Elementary School Student in the Transition to a Middle Level School.

    ERIC Educational Resources Information Center

    Odegaard, Sandra L.; Heath, Jay A.

    1992-01-01

    Through a review of the transition literature and a survey of 225 students about to enter middle school, the most significant anxieties identified were the following: (1) space concerns about a new and larger building, especially getting lost and being late to class; (2) contact with older and possibly rougher students; and (3) heavy homework…

  20. 32 CFR 1633.6 - Consideration of classes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... considered the lowest class, according to the following table: Class 1-A-O: Conscientious Objector Available for Noncombatant Military Service Only. Class 1-O: Conscientious Objector to all Military Service. Class 1-O-S: Conscientious Objector to all Military Service (Separated). Class 2-D: Registrant...

  1. Using Stimulus Equivalence-Based Instruction to Teach Graduate Students in Applied Behavior Analysis to Interpret Operant Functions of Behavior

    ERIC Educational Resources Information Center

    Albright, Leif; Schnell, Lauren; Reeve, Kenneth F.; Sidener, Tina M.

    2016-01-01

    Stimulus equivalence-based instruction (EBI) was used to teach four, 4-member classes representing functions of behavior to ten graduate students. The classes represented behavior maintained by attention (Class 1), escape (Class 2), access to tangibles (Class 3), and automatic reinforcement (Class 4). Stimuli within each class consisted of a…

  2. 46 CFR 147.40 - Materials requiring Commandant (CG-522) approval.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... HAZARDOUS SHIPS' STORES Stowage and Other Special Requirements for Particular Materials § 147.40 Materials... hazardous materials may be on board a vessel as ships' stores: (1) Poison gases of Class 2, Division 2.3 and... 46 Shipping 5 2010-10-01 2010-10-01 false Materials requiring Commandant (CG-522) approval....

  3. 19 CFR 151.45 - Storage tanks bonded as warehouses.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Storage tanks bonded as warehouses. 151.45 Section... Products § 151.45 Storage tanks bonded as warehouses. (a) Application. Tanks for the storage of imported petroleum or petroleum products in bulk may be bonded as warehouses of class 2 if to be used exclusively...

  4. 49 CFR 192.611 - Change in class location: Confirmation or revision of maximum allowable operating pressure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of maximum allowable operating pressure. (a) If the hoop stress corresponding to the established... locations. The corresponding hoop stress may not exceed 72 percent of the SMYS of the pipe in Class 2... pressure per § 192.620, the corresponding hoop stress may not exceed 80 percent of the SMYS of the pipe...

  5. The Question as a Technique in Foreign-Language Teaching. ERIC Focus Reports on the Teaching of Foreign Languages, Number 26.

    ERIC Educational Resources Information Center

    Harrell, Dolly D.

    This report focuses on the nature and structure of the question and its use as an educational technique enabling the language teacher to involve his students in the use of the target language. Discussion concentrates on: (1) the question in the basic level class, (2) the question as a testing technique, (3) the question as a vocabulary activator…

  6. 19 CFR 151.45 - Storage tanks bonded as warehouses.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Products § 151.45 Storage tanks bonded as warehouses. (a) Application. Tanks for the storage of imported petroleum or petroleum products in bulk may be bonded as warehouses of class 2 if to be used exclusively for the storage of petroleum or petroleum products belonging or consigned to the owner or lessee of...

  7. 19 CFR 151.45 - Storage tanks bonded as warehouses.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Products § 151.45 Storage tanks bonded as warehouses. (a) Application. Tanks for the storage of imported petroleum or petroleum products in bulk may be bonded as warehouses of class 2 if to be used exclusively for the storage of petroleum or petroleum products belonging or consigned to the owner or lessee of...

  8. A Comparison of Selected Transfer Students with a Matched Population of Native Students.

    ERIC Educational Resources Information Center

    Hartman, Eugene L.

    At the end of their junior year, in three colleges of the University of Missouri, junior college transfers were compared with native students, using as criteria (1) size of high school graduating class, (2) high school rank, (3) sex, (4) age at college entrance, and (5) the college of the University chosen for the junior year. The colleges were…

  9. 23 CFR 750.105 - Signs that may be permitted in protected areas.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... specific interest of the traveling public. Signs authorized to be erected or maintained by State law which... which are designed to give information in the specific interest of the traveling public. (b) A Class 2... phenomena, historic sites, areas of natural scenic beauty or naturally suited for outdoor recreation...

  10. 40 CFR 720.45 - Information that must be included in the notice form.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... rules and conventions). In addition, for a Class 2 substance, the notice must identify the immediate... reactant actually charged to the reaction vessel, or (B) the minimum weight of monomer or other reactant... chemical identity of the reported substance and its proprietary reactant. In addition, the...

  11. 40 CFR 720.45 - Information that must be included in the notice form.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... rules and conventions). In addition, for a Class 2 substance, the notice must identify the immediate... reactant actually charged to the reaction vessel, or (B) the minimum weight of monomer or other reactant... chemical identity of the reported substance and its proprietary reactant. In addition, the...

  12. 40 CFR 720.45 - Information that must be included in the notice form.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... rules and conventions). In addition, for a Class 2 substance, the notice must identify the immediate... reactant actually charged to the reaction vessel, or (B) the minimum weight of monomer or other reactant... chemical identity of the reported substance and its proprietary reactant. In addition, the...

  13. 46 CFR 170.250 - Types and classes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REQUIREMENTS FOR ALL INSPECTED VESSELS Watertight Bulkhead Doors § 170.250 Types and classes. (a) Watertight doors, except doors between cargo spaces, are classed as follows: (1) Class 1—Hinged door. (2) Class 2—Sliding door, operated by hand gear only. (3) Class 3—Sliding door, operated by power and by hand gear....

  14. Teaching Anthropogenic Climate Change through Interdisciplinary Collaboration: Helping Students Think Critically about Science and Ethics in Dialogue

    ERIC Educational Resources Information Center

    Todd, Claire; O'Brien, Kevin J.

    2016-01-01

    Anthropogenic climate change is a complicated issue involving scientific data and analyses as well as political, economic, and ethical issues. In order to capture this complexity, we developed an interdisciplinary student and faculty collaboration by (1) offering introductory lectures on scientific and ethical methods to two classes, (2) assigning…

  15. 49 CFR 229.129 - Locomotive horn.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Electrotechnical Commission (IEC) Standard 61672-1 (2002-05) for a Class 2 instrument. (2) An acoustic calibrator... ambient air temperature is between 32 degrees and 104 degrees Fahrenheit inclusively; relative humidity is... with the acoustic calibrator immediately before and after compliance tests. Any change in the...

  16. 49 CFR 229.129 - Locomotive horn.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Electrotechnical Commission (IEC) Standard 61672-1 (2002-05) for a Class 2 instrument. (2) An acoustic calibrator... ambient air temperature is between 32 degrees and 104 degrees Fahrenheit inclusively; relative humidity is... with the acoustic calibrator immediately before and after compliance tests. Any change in the...

  17. The Case-Tone Factor in Igbo Nouns, with Special Reference to the Igbo Associative Construction.

    ERIC Educational Resources Information Center

    Echeruo, Michael J. C.

    Tone-based classification rules for Igbo nouns need modification because: (1) class 1 nouns (monosyllables with high tones) do not, as claimed, operate differently from other terminal high-tone nouns; and (2) class 6 nouns (di-syllabic with downstep tones) can be accounted for within class 2 and class 3 nouns known as HH and LH nouns). The proper…

  18. In-Service Training Model for TESOL/ABE Teacher-Aides. Vol. 2.

    ERIC Educational Resources Information Center

    Southwestern Cooperative Educational Lab., Albuquerque, NM.

    This document contains discussion of each of the 10 objectives of the inservice program to prepare teachers and aides for the TESOL/ABE (Teaching English as a Second Language/Adult Basic Education) class. The objectives are to instruct participants in 1) the component parts of an ABE/TESOL class; 2) construction and design of visual aides such as…

  19. A Progress Report: The Relationship Between Mother-Infant Interaction and Sensory-Motor Development According to Age, Sex and Social Class Background.

    ERIC Educational Resources Information Center

    Curcio, Frank; And Others

    This paper describes the purposes and procedures of a longitudinal study designed to: (1) relate mother-infant interaction patterns to infant age, sex, and social class; (2) relate mother-infant interaction patterns to infant sensory-motor development; and (3) to examine the relationship between infant sensory-motor development and infant sex and…

  20. A Handbook on Latin America for Teachers: Methodology and Annotated Bibliography.

    ERIC Educational Resources Information Center

    Seelye, H. Ned, Ed.

    A product of a 1968 Title III National Defense Education Act Pilot Workshop on Teaching Latin American Cultural Themes, this booklet is designed to (1) further the cause of Latin American understanding in Spanish, social studies, and elementary school classes, (2) to be used in future workshops, and (3) serve as a model for similar handbooks…

  1. 49 CFR 176.210 - On deck stowage requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false On deck stowage requirements. 176.210 Section 176.210 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY VESSEL Detailed Requirements for Class 2 (Compressed...

  2. Drug Cartels and Gangs in Mexico and Central America: A View through the Lens of Counterinsurgency

    DTIC Science & Technology

    2010-06-04

    crime in today’s Central America. First, the institution of an Encomienda system of land ownership, which granted Spanish Conquistadors and upper class...2 Britannica on line, http://www.britannica.com/EBchecked/topic/186567/ encomienda (accessed October 15, 2009). 3 Net Industries, http

  3. 17 CFR 230.418 - Supplemental information.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the number of copies distributed to each such class; (2) In the case of a registration statement... offer or similar transaction, any feasibility studies, management analyses, fairness opinions or similar... transaction; (3) Except in the case of a registrant eligible to use Form S-3 (§ 239.13 of this chapter),...

  4. HEAVY-DUTY GREENHOUSE GAS EMISSIONS MODEL (GEM)

    EPA Science Inventory

    Class 2b-8 vocational truck manufacturers and Class 7/8 tractor manufacturers would be subject to vehicle-based fuel economy and emission standards that would use a truck simulation model to evaluate the impact of the truck tires and/or tractor cab design on vehicle compliance wi...

  5. 49 CFR 192.505 - Strength test requirements for steel pipeline to operate at a hoop stress of 30 percent or more...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... pressure. In addition, in a Class 1 or Class 2 location, if there is a building intended for human... (91 meters) of such a building, but in no event may the test section be less than 600 feet (183...

  6. 49 CFR 192.505 - Strength test requirements for steel pipeline to operate at a hoop stress of 30 percent or more...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION... pressure. In addition, in a Class 1 or Class 2 location, if there is a building intended for human... (91 meters) of such a building, but in no event may the test section be less than 600 feet (183...

  7. Emotional Psychological and Related Problems among Truant Youths: An Exploratory Latent Class Analysis

    ERIC Educational Resources Information Center

    Dembo, Richard; Briones-Robinson, Rhissa; Ungaro, Rocio Aracelis; Gulledge, Laura M.; Karas, Lora M.; Winters, Ken C.; Belenko, Steven; Greenbaum, Paul E.

    2012-01-01

    Intervention Project. Results identified two classes of youths: Class 1(n=9) - youths with low levels of delinquency, mental health and substance abuse issues; and Class 2(n=37) - youths with high levels of these problems. Comparison of these two classes on their urine analysis test results and parent/guardian reports of traumatic events found…

  8. Integrating Literature in Content Areas: Professional's Guide.

    ERIC Educational Resources Information Center

    Walley, Carl W.; Walley, Kate

    Based on the premise that viewing the curriculum holistically enriches the instructional practices of teachers and adds depth and meaning to children's school experiences, this guide is intended to: (1) encourage teachers who have doubts about using literature in their content area classes; (2) support those presently using literature to teach;…

  9. Determination of BROMATE AT PARTS-PER-TRILLION LEVELS BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY WITH NEGATIVE CHEMICAL IONIZATION

    EPA Science Inventory

    The ozonation of bromide-containing source waters produces bromate as a class 2B carcinogenic disinfection by-product. The present work describes the determination of bromate by gas chromatography-negative chemical ionization mass spectrometry (GC-NCIMS) following a bromate react...

  10. Eight-Year Trends in Federal Graduation Rates and Graduation Success Rates at NCAA Division I Institutions

    ERIC Educational Resources Information Center

    National Collegiate Athletic Association (NJ1), 2009

    2009-01-01

    Data is presented on: (1) Comparison of GSR and Federal Graduation Rate Cohorts (1999-2002 Entering Classes); (2) Average GSRs for Division I Student-Athletes in 1998-01 Cohorts Vs. 1999-2002 Cohorts; (3) Graduation Success Rate Trends for Division I Men's Sports: Four-Class Averages for 1998-01 Cohorts vs. 1999-02 Cohorts; (4) Graduation Success…

  11. Learning and Teaching in Large Classes: A Bibliography. Project Report No.1.

    ERIC Educational Resources Information Center

    Coleman, Hywel

    This bibliography has four major sections, including: (1) the learning and teaching of English in large classes; (2) the learning and teaching of other subjects in large classes; (3) class size and achievement; and (4) cultural background and large classes. Both published and unpublished materials are contained in the bibliography. The…

  12. Endocardial Lead Extraction in the Polish Registry – clinical practice versus current Heart Rhythm Society consensus

    PubMed Central

    Kutarski, Andrzej; Mitkowski, Przemysław; Przybylski, Andrzej; Lewek, Joanna; Małecka, Barbara; Smukowski, Tomasz; Maciąg, Aleksander; Śmigielski, Janusz

    2013-01-01

    Introduction Over the last 10 years, there has been an increasing number of patients with pacemaker (PM) and cardioverter-defibrillator (ICD). This study is a retrospective analysis of indications for endocardial pacemaker and ICD lead extractions between 2003 and 2009 based on the experience of three Polish Referral Lead Extraction Centers. Material and methods Since 2003, the authors have consecutively retrospectively collected all cases and entered the information in the database. All patients which had indication for lead extraction according to Heart Rhythm Society Guidelines were included to final analyze. Between 2003 and 2005, the data were analyzed together. Since 2006, data have been collected and analyzed annually. Results In each year, a significant increase in lead extraction was observed. The main indications for LE were infections in 52.4% of patients. Nonfunctioning lead extraction constituted the second group of indications for LE in 29.7% of patients. During the registry period, the percentage of class I indications decreased from 80% in 2006 to only 47% in 2009. On the other hand, increasingly more leads were removed because of class 2, especially class 2b. In 2009, 40% of leads were extracted due to class 2b. Conclusions Polish Registry of Endocardial Lead Extraction 2003-2009, shows an increasing frequency of lead extraction. The main indication for LE is infection: systemic and pocket. An increase in class 2, especially 2b, LE indication in every center during the study period was found. PMID:24904658

  13. Assessing College Student Use of Anti-Citizenship Classroom Behavior: Types, Reasons, and Association with Learning Outcomes

    ERIC Educational Resources Information Center

    Myers, Scott A.; Goldman, Zachary W.; Ball, Hannah; Carton, Shannon T.; Atkinson, Jordan; Tindage, Melissa F.; Anderson, Amena O.

    2015-01-01

    This assessment examined the presence of anti-citizenship behavior (ACB) in the college classroom by (1) identifying the types of ACB college students use in their classes, (2) identifying the reasons why students use ACB, and (3) exploring the link between ACB and student learning outcomes. The results indicated that (1) participants report four…

  14. The Effect of Glycolytic Modulation on Prostate Cancer

    DTIC Science & Technology

    2010-07-01

    NYHA Class 2, 3, or 4; New York Heart Association Criteria) within the last 6 months, particularly coronary artery disease , arrhyth- mias, or...Medicine and Dentistry of NJ New Brunswick, NJ 08901 REPORT DATE: July 2010 TYPE OF REPORT: Final PREPARED FOR: U.S...ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER University of Medicine and Dentistry of NJ New Brunswick, NJ 08901

  15. 33 CFR 183.540 - Hoses: Standards and markings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 1 hose has a permeation rating of 100 grams or less fuel loss per square meter of interior surface in 24 hours. SAE Class 2 hose has a permeation rating of 300 grams or less fuel loss per square meter.... (g) Each character must be block capital letters and numerals that are at least one eighth-inch...

  16. A critical review on the improvement of photosynthetic carbon assimilation in C3 plants using genetic engineering.

    PubMed

    Ruan, Cheng-Jiang; Shao, Hong-Bo; Teixeira da Silva, Jaime A

    2012-03-01

    Global warming is one of the most serious challenges facing us today. It may be linked to the increase in atmospheric CO2 and other greenhouse gases (GHGs), leading to a rise in sea level, notable shifts in ecosystems, and in the frequency and intensity of wild fires. There is a strong interest in stabilizing the atmospheric concentration of CO2 and other GHGs by decreasing carbon emission and/or increasing carbon sequestration. Biotic sequestration is an important and effective strategy to mitigate the effects of rising atmospheric CO2 concentrations by increasing carbon sequestration and storage capacity of ecosystems using plant photosynthesis and by decreasing carbon emission using biofuel rather than fossil fuel. Improvement of photosynthetic carbon assimilation, using transgenic engineering, potentially provides a set of available and effective tools for enhancing plant carbon sequestration. In this review, firstly different biological methods of CO2 assimilation in C3, C4 and CAM plants are introduced and three types of C4 pathways which have high photosynthetic performance and have evolved as CO2 pumps are briefly summarized. Then (i) the improvement of photosynthetic carbon assimilation of C3 plants by transgenic engineering using non-C4 genes, and (ii) the overexpression of individual or multiple C4 cycle photosynthetic genes (PEPC, PPDK, PCK, NADP-ME and NADP-MDH) in transgenic C3 plants (e.g. tobacco, potato, rice and Arabidopsis) are highlighted. Some transgenic C3 plants (e.g. tobacco, rice and Arabidopsis) overexpressing the FBP/SBPase, ictB and cytochrome c6 genes showed positive effects on photosynthetic efficiency and growth characteristics. However, over the last 28 years, efforts to overexpress individual, double or multiple C4 enzymes in C3 plants like tobacco, potato, rice, and Arabidopsis have produced mixed results that do not confirm or eliminate the possibility of improving photosynthesis of C3 plants by this approach. Finally, a prospect

  17. Seasonal influences on carbohydrate metabolism in the CAM bromeliad Aechmea ‘Maya’: consequences for carbohydrate partitioning and growth

    PubMed Central

    Ceusters, Johan; Borland, Anne M.; Ceusters, Nathalie; Verdoodt, Veerle; Godts, Christof; De Proft, Maurice P.

    2010-01-01

    Background and Aims Photosynthetic plasticity in response to a range of environmental factors that include [CO2], water availability, light intensity and temperature, is ubiquitous among plants with crassulacean acid metabolism (CAM). The present study examined how seasonal changes in light availability, as experienced by greenhouse CAM crops in northern latitude regions, influence diel carboxylation patterns and impact on carbon gain and seasonal accumulation of biomass. Methods In the CAM bromeliad Aechmea ‘Maya’ integrated measurements of leaf gas exchange, diel metabolite dynamics (e.g. malate, soluble sugars and starch) and biomass accumulation were made four times a year, i.e. in winter, spring, summer and autumn. Key Results During the brighter seasons (spring and summer) daytime Phases II and IV were dominated by C4 carboxylation, whilst the higher diurnal uptake in the autumn and winter was characterized by equal contributions of both Rubisco and PEPC. As a consequence, net CO2 uptake showed a significant depression at the end of the day in the darker months when supplementary illumination was turned off. Remarkable seasonal consistency was found in the amount of storage reserves available for nocturnal carboxylation, a consequence of predominantly daytime export of carbohydrate in spring and summer whilst nocturnal export was the major sink for carbohydrate in autumn and winter. Conclusions Throughout the different seasons Aechmea ‘Maya’ showed considerable plasticity in the timing and magnitude of C3 and C4 carboxylation processes over the diel cycle. Under low PPFD (i.e. winter and autumn) it appears that there was a constraint on the amount of carbohydrate exported during the day in order to maintain a consistent pool of transient carbohydrate reserves. This gave remarkable seasonal consistency in the amount of storage reserves available at night, thereby optimizing biomass gain throughout the year. The data have important practical

  18. Milk phospholipids: Organic milk and milk rich in conjugated linoleic acid compared with conventional milk.

    PubMed

    Ferreiro, T; Gayoso, L; Rodríguez-Otero, J L

    2015-01-01

    CLA-rich milk production included linseed supplement and contained less maize meal than conventional rations and a greater proportion of unsaturated fatty acids and salts. The relative proportions of the phospholipids studied were similar in all 3 types of milk, descending in the order PE>(PC, SM)>PS>PI, with PC being slightly more abundant than SM in organic milk and vice versa in CLA-rich milk.

  19. Parallel Eclipse Project Checkout

    NASA Technical Reports Server (NTRS)

    Crockett, Thomas M.; Joswig, Joseph C.; Shams, Khawaja S.; Powell, Mark W.; Bachmann, Andrew G.

    2011-01-01

    Parallel Eclipse Project Checkout (PEPC) is a program written to leverage parallelism and to automate the checkout process of plug-ins created in Eclipse RCP (Rich Client Platform). Eclipse plug-ins can be aggregated in a feature project. This innovation digests a feature description (xml file) and automatically checks out all of the plug-ins listed in the feature. This resolves the issue of manually checking out each plug-in required to work on the project. To minimize the amount of time necessary to checkout the plug-ins, this program makes the plug-in checkouts parallel. After parsing the feature, a request to checkout for each plug-in in the feature has been inserted. These requests are handled by a thread pool with a configurable number of threads. By checking out the plug-ins in parallel, the checkout process is streamlined before getting started on the project. For instance, projects that took 30 minutes to checkout now take less than 5 minutes. The effect is especially clear on a Mac, which has a network monitor displaying the bandwidth use. When running the client from a developer s home, the checkout process now saturates the bandwidth in order to get all the plug-ins checked out as fast as possible. For comparison, a checkout process that ranged from 8-200 Kbps from a developer s home is now able to saturate a pipe of 1.3 Mbps, resulting in significantly faster checkouts. Eclipse IDE (integrated development environment) tries to build a project as soon as it is downloaded. As part of another optimization, this innovation programmatically tells Eclipse to stop building while checkouts are happening, which dramatically reduces lock contention and enables plug-ins to continue downloading until all of them finish. Furthermore, the software re-enables automatic building, and forces Eclipse to do a clean build once it finishes checking out all of the plug-ins. This software is fully generic and does not contain any NASA-specific code. It can be applied to any

  20. Radiation-induced hemopoietic and immune dysfunction. Technical report, 16 Aug 86-31 Mar 90

    SciTech Connect

    Storb, R.; Schuening, F.

    1991-06-01

    This work was aimed at investigating radiation-induced hemopoietic and immune dysfunction in the dog model. One project was to produce monoclonal antibodies directed against canine hemopoietic precursor cells and specific for pluripotent stem cells. Antibodies obtained reacted with different myeloid and erythroid precursor cells; unfortunately, none of the antibodies were specific for pluripotent hemopoietic stem cells. Positive selections for these cells were performed using magnetic beads and an antibody against class 2-antigen. Transplantation of class 2 positive marrow cells into otherwise lethally irradiated dogs led to sustained recovery in only 1 of 5 dogs. A second project established and investigated long-term marrow cultures in the dog. Culture conditions were studied and optimized, and marrow cells were transplanted into otherwise lethally irradiated dogs to investigate stem cell survival in long-term cultures. Engraftment was observed only with short-term marrow cultures.

  1. Plant hemoglobins: important players at the crossroads between oxygen and nitric oxide.

    PubMed

    Gupta, Kapuganti J; Hebelstrup, Kim H; Mur, Luis A J; Igamberdiev, Abir U

    2011-12-15

    Plant hemoglobins constitute a diverse group of hemeproteins and evolutionarily belong to three different classes. Class 1 hemoglobins possess an extremely high affinity to oxygen and their main function consists in scavenging of nitric oxide (NO) at very low oxygen levels. Class 2 hemoglobins have a lower oxygen affinity and they facilitate oxygen supply to developing tissues. Symbiotic hemoglobins in nodules have mostly evolved from class 2 hemoglobins. Class 3 hemoglobins are truncated and represent a clade with a very low similarity to class 1 and 2 hemoglobins. They may regulate oxygen delivery at high O(2) concentrations. Depending on their physical properties, hemoglobins belong either to hexacoordinate non-symbiotic or pentacoordinate symbiotic groups. Plant hemoglobins are plausible targets for improving resistance to multiple stresses.

  2. Preliminary safety evaluation (PSE) for Sodium Storage Facility at the Fast Flux Test Facility

    SciTech Connect

    Bowman, B.R.

    1994-09-30

    This evaluation was performed for the Sodium Storage Facility (SSF) which will be constructed at the Fast Flux Test Facility (FFTF) in the area adjacent to the South and West Dump Heat Exchanger (DHX) pits. The purpose of the facility is to allow unloading the sodium from the FFTF plant tanks and piping. The significant conclusion of this Preliminary Safety Evaluation (PSE) is that the only Safety Class 2 components are the four sodium storage tanks and their foundations. The building, because of its imminent risk to the tanks under an earthquake or high winds, will be Safety Class 3/2, which means the building has a Safety Class 3 function with the Safety Class 2 loads of seismic and wind factored into the design.

  3. [Three wavelengths factor model of chlorophyll concentrations inversion based on different spectral dominating factors for inland lake].

    PubMed

    Shi, Kun; Li, Yun-Mei; Liu, Zhong-Hua; Xu, Yi-Fan; Xu, Xini; Wu, Chuan-Qing; Zhu, Li

    2010-12-01

    A hierarchical cluster analysis is applied to the data set of R(rs) spectra. Combing the inherent optical and measured water color characteristics, we determine factors of the variability for each class of R(rs) spectra. The R(rs) measured from Lake Taihu, Chaohu, Dianchi and Three Gorges Reservoir can be divided into three spectrally distinct classes: class 1, class 2 and class 3. Class 1 is associated with water optical property dominated by total suspended matter and phytoplankton. Class 2 is associated with water optical property dominated by phytoplankton. And Class 3 is associated with water optical property dominated by total suspended matter. The three wavelengths factor Chlorophyll a concentration inversion models were developed according to different class water optical characteristics, which means relative error and RMSE are 23.8% and 8.5 mg/m3, and have higher accuracy than the model developed without classification.

  4. 27 CFR 4.21 - The standards of identity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... characteristics generally attributed to angelica, madeira, muscatel and port and an alcoholic content, derived in... “angelica,” “madeira,” “muscatel,” or “port” respectively. Dessert wines having the taste, aroma, and...,” “light angelica,” “light madeira,” “light muscatel” or “light port,” respectively. (b) Class 2;...

  5. 27 CFR 4.21 - The standards of identity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... characteristics generally attributed to angelica, madeira, muscatel and port and an alcoholic content, derived in... “angelica,” “madeira,” “muscatel,” or “port” respectively. Dessert wines having the taste, aroma, and...,” “light angelica,” “light madeira,” “light muscatel” or “light port,” respectively. (b) Class 2;...

  6. 27 CFR 4.21 - The standards of identity.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... characteristics generally attributed to angelica, madeira, muscatel and port and an alcoholic content, derived in... “angelica,” “madeira,” “muscatel,” or “port” respectively. Dessert wines having the taste, aroma, and...,” “light angelica,” “light madeira,” “light muscatel” or “light port,” respectively. (b) Class 2;...

  7. 27 CFR 4.21 - The standards of identity.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... characteristics generally attributed to angelica, madeira, muscatel and port and an alcoholic content, derived in... “angelica,” “madeira,” “muscatel,” or “port” respectively. Dessert wines having the taste, aroma, and...,” “light angelica,” “light madeira,” “light muscatel” or “light port,” respectively. (b) Class 2;...

  8. System 80+{trademark} Standard Design: CESSAR design certification. Volume 7

    SciTech Connect

    1997-12-31

    This report has been prepared in support of the industry effort to standardize nuclear plant designs. This document describes the Combustion Engineering, Inc. System 80+{trademark} Standard Design. This volume contains sections 4 thru 8 of Chapter 6 -- Engineered Safety Features. Topics covered include: habitability systems; containment spray systems; inservice inspection of class 2 and 3 components; safety depressurization system; and in-containment water storage system. Also included are Appendices 6A, 6B, and 6C.

  9. Survey of Munitions Response Technologies

    DTIC Science & Technology

    2006-06-01

    Va.). Table 2-1. Site difficulty levels used in vegetation removal. Class Vegetation Terrain Obstacles Class 1 (easy) Light grass and vegetation up...to 2 feet high. Fairly level terrain. Minimal debris and obstacles . Class 2 (moderate) Moderate vegetation with sparse brush 2 to 4 feet high...Level to light rolling terrain with some ruts. Some debris and obstacles . Class 3 (difficult) Moderate vegetation with brush, saplings, and

  10. Nested Fork-Join Queuing Networks and Their Application to Mobility Airfield Operations Analysis.

    DTIC Science & Technology

    1997-03-01

    Method. The accuracy of this approximation is similar to that of its single-class counterpart. A similar approach is used by Di Mascolo, Frein , Baynat and...customer causes n 2 class 2 departures, and stays at station] The states with which (0, n 2) communicates , as well as the appropriate transition rates...In this case, states exist where both nl and n2 are nonzero. The states with which (nj, n2) communicates , together with the appropriate transition

  11. Expression and evolution of functionally distinct haemoglobin genes in plants.

    PubMed

    Hunt, P W; Watts, R A; Trevaskis, B; Llewelyn, D J; Burnell, J; Dennis, E S; Peacock, W J

    2001-11-01

    Haemoglobin genes have been found in a number of plant species, but the number of genes known has been too small to allow effective evolutionary inferences. We present nine new non-symbiotic haemoglobin sequences from a range of plants, including class 1 haemoglobins from cotton, Citrus and tomato, class 2 haemoglobins from cotton, tomato, sugar beet and canola and two haemoglobins from the non-vascular plants, Marchantia polymorpha (a liverwort) and Physcomitrella patens (a moss). Our molecular phylogenetic analysis of all currently known non-symbiotic haemoglobin genes and a selection of symbiotic haemoglobins have confirmed the existence of two distinct classes of haemoglobin genes in the dicots. It is likely that all dicots have both class 1 and class 2 non-symbiotic haemoglobin genes whereas in monocots we have detected only class 1 genes. The symbiotic haemoglobins from legumes and Casuarina are related to the class 2 non-symbiotic haemoglobins, whilst the symbiotic haemoglobin from Parasponia groups with the class 1 non-symbiotic genes. Probably, there have been two independent recruitments of symbiotic haemoglobins. Although the functions of the two non-symbiotic haemoglobins remain unknown, their patterns of expression within plants suggest different functions. We examined the expression in transgenic plants of the two non-symbiotic haemoglobins from Arabidopsis using promoter fusions to a GUS reporter gene. The Arabidopsis GLB1 and GLB2 genes are likely to be functionally distinct. The class 2 haemoglobin gene (GLB2) is expressed in the roots, leaves and inflorescence and can be induced in young plants by cytokinin treatment in contrast to the class 1 gene (GLB1) which is active in germinating seedlings and can be induced by hypoxia and increased sucrose supply, but not by cytokinin treatment.

  12. 33 CFR 183.540 - Hoses: Standards and markings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) SAE Standard J1527DEC85, Class 1 and the fire test in § 183.590; or (2) Underwriters' Laboratories... SAE Standard J1527DEC85, Class 2 and the fire test in § 183.590; (c) “USCG Type B1” hose means hose that meets the performance requirements of SAE Standard J1527DEC85, Class 1. (d) “USCG Type B2”...

  13. 33 CFR 183.540 - Hoses: Standards and markings.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) SAE Standard J1527DEC85, Class 1 and the fire test in § 183.590; or (2) Underwriters' Laboratories... SAE Standard J1527DEC85, Class 2 and the fire test in § 183.590; (c) “USCG Type B1” hose means hose that meets the performance requirements of SAE Standard J1527DEC85, Class 1. (d) “USCG Type B2”...

  14. 33 CFR 126.27 - General permit for handling dangerous cargo.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... waterfront facility solely for transfer to or from a railroad-car ferry, highway-vehicle ferry, or carfloat... excess of 36,400 kg (40 net tons) at any one time. (2) Class 2, Division 2.1 (Flammable Gas) materials in bulk packaging; or Division 2.3 (Poison Gas) materials in excess of 72,800 kg (80 net tons) at any...

  15. 33 CFR 126.27 - General permit for handling dangerous cargo.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... waterfront facility solely for transfer to or from a railroad-car ferry, highway-vehicle ferry, or carfloat... excess of 36,400 kg (40 net tons) at any one time. (2) Class 2, Division 2.1 (Flammable Gas) materials in bulk packaging; or Division 2.3 (Poison Gas) materials in excess of 72,800 kg (80 net tons) at any...

  16. Symposium on Toxic Substance Control: Decontamination, April 22 - 24, 1980, Columbus, Ohio.

    DTIC Science & Technology

    1981-06-01

    Slask. Inz. and Sanit., 13, 95-112 (1969). (6) Netzer, A., Bowers, A., and Norman, J. D., "Removal of Trace Metals from Wastewater by Lime and...Rubber and Elastomers Materials NR Natural Rubber IR Synthetic Isoprene, MIL-R-6855, Class 2 IIR Isobutene-Isoprene BR Polybutadiene SBR Styrene...problem areas in a battlefield hospital were also discussed. In regard to detection, the medical community really does not know how to assess the

  17. A Privacy-Protecting Authentication Scheme for Roaming Services with Smart Cards

    NASA Astrophysics Data System (ADS)

    Son, Kyungho; Han, Dong-Guk; Won, Dongho

    In this work we propose a novel smart card based privacy-protecting authentication scheme for roaming services. Our proposal achieves so-called Class 2 privacy protection, i.e., no information identifying a roaming user and also linking the user's behaviors is not revealed in a visited network. It can be used to overcome the inherent structural flaws of smart card based anonymous authentication schemes issued recently. As shown in our analysis, our scheme is computationally efficient for a mobile user.

  18. The Social Development of Two Year Old Children in Residential Nurseries.

    ERIC Educational Resources Information Center

    Tizard, Jack; Tizard, Barbara

    This study focuses upon some aspects of the social behavior of 2-year-old children being reared in long-stay residential nurseries. These children are compared with working class 2-year-old children being raised in two-parent homes in which the mother is not working full-time and there are no older siblings of preschool age. All children were…

  19. Tests of a Prior Marksmanship Knowledge Predictor Test

    DTIC Science & Technology

    2014-01-01

    Christopher L. Vowels, U.S. Army Research Institute Peter S. Schaefer, U.S. Army Research Institute NOTICES DISTRIBUTION: Primary...Duty 95 Active Guard Reserve ( AGR ) 6 * - One student left the service status blank. Note: PV2 = Private E-2; SFC = Sergeant First Class...2. Branch of Service (n = 102) Air Force Army 0 102 3. Current Service Status (n = 101) Active Duty Active Guard Reserve ( AGR ) 95 6

  20. A Note on Twin Primes and the Modular Ring Z[subscript 6

    ERIC Educational Resources Information Center

    Leyendekkers, J. V.; Shannon, A. G.

    2002-01-01

    The modular ring Z[subscript 6] defines integers via ( 6r[subscript i] + ( i - 3)) where i is the class and r[subscript i] the row when tabulated in an array. Since only Classes 2[subscipt 6] and 4[subscript 6] contain odd primes, this modular ring is ideally suited to the analysis of twin primes. The calculations are facilitated by the use of the…

  1. Subtypes of Adolescent Sedative/Anxiolytic Misusers: A Latent Profile Analysis

    PubMed Central

    Hall, Martin T.; Howard, Matthew O.; McCabe, Sean Esteban

    2010-01-01

    Background Few empirically-based taxonomies of nonmedical prescription drug misusers have been published. This study used latent profile analysis (LPA) to identify classes of adolescent sedative/anxiolytic misusers. Methods Interviews assessing substance use, psychiatric symptoms, antisocial traits/behavior, and traumatic life experiences were conducted with 723 Missouri youth in residential care for antisocial behavior. Sedative/anxiolytic misusers (N = 247) averaged 15.8 (S.D. = 1.1) years of age; a majority were male (83.8%), White (70.0%), and resided in rural/small town areas (53.8%). Results LPA yielded a three-class solution. Class 1 (59.1%) was comprised of youth with significantly lower levels of currently distressing psychiatric symptoms, fewer lifetime traumatic experiences, less problematic substance use histories, less frequent antisocial behavior, and less impulsivity than youth in Classes 2 and 3. Class 2 (11.3%) youth had high levels of currently distressing psychiatric symptoms and more frequent antisocial behavior compared to youth in Classes 1 and 3. Class 3 (29.5%) youth evidenced levels of psychiatric and behavioral problems that were intermediate to those of Class 1 and 2 youth. Frequency of sedative/anxiolytic misuse was significantly higher in Classes 2 and 3 compared to Class 1. Members of Class 2 and Class 3 also had the highest levels of psychiatric symptoms for which sedatives/anxiolytics are commonly prescribed. Significant differences between classes were observed across a range of health, mental health, personality, and behavioral variables. Conclusions Adolescents who misused prescription sedatives/anxiolytics evidenced significant heterogeneity across measures of psychiatric and behavioral dysfunction. Youth with comparatively high levels of anxiety and depression reported significantly more intensive sedative/anxiolytic misuse than their counterparts and may be at high risk for sedative/anxiolytic abuse and dependence. PMID

  2. Active Contours for Multispectral Images With Non-Homogeneous Sub-Regions

    DTIC Science & Technology

    2005-09-16

    green , and blue. Hyperspectral images, used in remote sensing, are other examples of multispectral im- ages. A set of images, measured by physically...method 1, (b) method 2, (c) proposed method The green solid line of all three graphs presents the same statistics measured within class 2 in the...segmentation result. As the green solid line exists closer to the blue solid line, it presents better result. In figure 8.7(a), the dotted green line with

  3. All States Guide to Consumer Laws.

    DTIC Science & Technology

    1986-09-01

    2-18 c. Treatment of classified claims ............. 2-18 2. Plan Variations ............................. 2-18 a. Designation of...provide for the same treatment of such claim within a particular class. 2. The Plan may: a. Designate a class or classes of unsecured claims, but may not... treatment is specifically permitted under the BAFJA amendments. (2) Treat returned checks as a separate class and provide for them to be paid early

  4. Demonstration of the Berkeley UXO Discrimination at Live Sites

    DTIC Science & Technology

    2010-02-01

    class( j )class( j )class( 2/))class(extrapfeatn( feat)n()vv()C()vv(1 1K)v(f (2) with γ = 0.2986/(nfeat + ) (3a) )class( extrap ...2. )class( extrap 19 Equation (2) is a generalization of a Cauchy distribution. As approaches infinity the distribution approaches a Gaussian...for very heavy tailed distributions. Empirical probability densities were estimated separately for UXO and scrap classes. )class( extrap )class

  5. Dating Violence Perpetration and Victimization among US Adolescents: Prevalence, Patterns, and Associations with Health Complaints and Substance Use

    PubMed Central

    Farhat, Tilda; Brooks-Russell, Ashley; Wang, Jing; Barbieri, Brittney; Iannotti, Ronald J.

    2013-01-01

    Purpose This research identified conceptually cohesive latent classes of youth dating violence (DV) and examined associations between covariates and classes by gender. Methods A nationally representative sample of 2,203 tenth-grade students completed assessments of physical and verbal DV victimization and perpetration, depressive symptoms, health complaints, and substance use. A Factor Mixture Model was used to identify patterns of DV. Gender differences among classes were examined for depressive symptoms, health complaints, and substance use. Results Prevalence of DV victimization was 35% and perpetration was 31%. A three-class model fit adequately and provided conceptual cohesion: Class 1) non-involved (65%); Class 2) victims/perpetrators of verbal DV (30%); and Class 3) victims/perpetrators of verbal and physical DV (5%). Compared to Class 1 adolescents, those in Classes 2 and 3 were more likely to report depressive symptoms, psychological complaints, and alcohol use. Females in Classes 2 and 3 were also more likely to report physical complaints, cigarette use, and marijuana use. Among females involved in DV, those in Class 3 compared to Class 2 reported more depressive symptoms, physical and psychological complaints, and cigarette and marijuana use. Conclusions The three-class model distinguished involvement in verbal acts from involvement in verbal and physical acts. Adolescents involved in DV had similar probabilities of reporting perpetration and victimization suggesting violence within relationships may be mutual. Involvement in DV was associated with more health issues and concurrent problem behaviors. For females in particular, the increased involvement in DV was associated with other health indicators. PMID:23664626

  6. Matter-wave exact periodic solutions in optical lattices with periodic potential

    NASA Astrophysics Data System (ADS)

    Liu, Changfu; Zhu, Aijun

    2013-10-01

    Some special matter-wave periodic solutions for the Gross-Pitaevskii equation with periodic potential in the multidimensional optical lattices, are obtained through restricting parameters and some balance conditions between the optical potentials and interaction energies. The results show that the same type of periodic solutions in the same dimension possesses the same norm but different phases and they are all bounded. Especially, the numerics shows that two class (2+1)-dimensional periodic solutions are stable.

  7. Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf Carbonate Reservoir, Class II

    SciTech Connect

    Hickman, T. Scott; Justice, James J.; Egg, Rebecca

    2001-08-07

    The Oxy operated Class 2 Project at West Welch Project is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO2 injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir demonstration characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO2 flood design based on the reservoir characterization.

  8. More improvement than progression of liver fibrosis following antiretroviral therapy in a longitudinal cohort of HIV-infected patients with or without HBV and HCV co-infections.

    PubMed

    Ding, Y; Duan, S; Ye, R; Yang, Y; Yao, S; Wang, J; Cao, D; Liu, X; Lu, L; Jia, M; Wu, Z; He, N

    2016-12-07

    We examined the effect of combination antiretroviral therapy (cART) on liver fibrosis among HIV-infected patients with or without hepatitis B (HBV) or C virus (HCV) co-infection. This was a retrospective cohort study of HIV-infected patients receiving cART during 2004-2016. Liver fibrosis was assessed using Fibrosis-4 (FIB-4) score with three classifications: Class 1, <1.45; Class 2, 1.45-3.25; Class 3, >3.25. Of 3900 participants, 68.6% were HIV mono-infected, 5.3% were HIV/HBV co-infected, 23.8% were HIV/HCV co-infected and 2.3% were HIV/HBV/HCV co-infected. Participants received follow-up treatment (median was 3.3 years). Improvement to a lower class was observed in Class 2 (52.6%) and Class 3 (74.2%), respectively. Progression to a higher class was observed in 12.8% and 5.0% in Class 1 and Class 2, respectively, and with a median time of 5.7 months. For improvement to lower classes, older age, male, Dai ethnicity, injection drug use, HCV co-infection and tenofovir for treatment were negative predictors, but in Class 3 of FIB-4 and time-updated increases in CD4 count from baseline were positive predictors. For progression to higher classes, older age, male, Jingpo ethnicity and HCV co-infection were positive predictors, while baseline CD4 count and in Class 2 of FIB-4 were negative predictors. Improvement to lower class linked with decreased mortality risk among patients in Class 3. Early cART initiation for HIV-infected patients with and without hepatitis co-infections may mitigate or slow down some of liver fibrosis, but special attention should be given to those who are older, male, co-infected with HCV.

  9. Evaluations of 1997 Fuel Consumption Patterns of Heavy Duty Trucks

    SciTech Connect

    Santini, Danilo

    2001-08-05

    The proposed 21st Century Truck program selected three truck classes for focused analysis. On the basis of gross vehicle weight (GVW) classification, these were Class 8 (representing heavy), Class 6 (representing medium), and Class 2b (representing light). To develop and verify these selections, an evaluation of fuel use of commercial trucks was conducted, using data from the 1997 Vehicle Inventory and Use Survey (VIUS). Truck fuel use was analyzed by registered GVW class, and by body type.

  10. Is Tyre Macula an ice cauldron?

    NASA Astrophysics Data System (ADS)

    Thomas, Constantine

    1997-03-01

    Tyre Macula is a large, dark circular feature on Europa, classified first by Lucchita and Soderblom (1982) as a 'Class 2' impact feature similar in nature to the crater palimpsests on Ganymede. It lies near the junction of several dark lineaments, and exhibits several features that throw doubt on an impact origin. Here I propose that Tyre Macula is actually a large ice cauldron, a feature created by local ice subsidence as a result of subsurface geothermal heating on Europa.

  11. A non-synonymous polymorphism in IRS1 modifies risk of developing breast and ovarian cancers in BRCA1 and ovarian cancer in BRCA2 mutation carriers

    PubMed Central

    Ding, Yuan C.; McGuffog, Lesley; Healey, Sue; Friedman, Eitan; Laitman, Yael; Shani-Shimon–Paluch; Kaufman, Bella; Liljegren, Annelie; Lindblom, Annika; Olsson, Håkan; Kristoffersson, Ulf; Stenmark-Askmalm, Marie; Melin, Beatrice; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Gronwald, Jacek; Huzarski, Tomasz; Cybulski, Cezary; Byrski, Tomasz; Osorio, Ana; Cajal, Teresa Ramóny; Stavropoulou, Alexandra V; Benítez, Javier; Hamann, Ute; Rookus, Matti; Aalfs, Cora M.; de Lange, Judith L.; Meijers-Heijboer, Hanne E.J.; Oosterwijk, Jan C.; van Asperen, Christi J.; García, Encarna B. Gómez; Hoogerbrugge, Nicoline; Jager, Agnes; van der Luijt, Rob B.; Easton, Douglas F.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Lalloo, Fiona; Izatt, Louise; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Brewer, Carole; Tischkowitz, Marc; Godwin, Andrew K.; Pathak, Harsh; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M.; Mazoyer, Sylvie; Barjhoux, Laure; Léoné, Mélanie; Gauthier-Villars, Marion; Caux-Moncoutier, Virginie; de Pauw, Antoine; Hardouin, Agnès; Berthet, Pascaline; Dreyfus, Hélène; Ferrer, Sandra Fert; Collonge-Rame, Marie-Agnès; Sokolowska, Johanna; Buys, Saundra; Daly, Mary; Miron, Alex; Terry, Mary Beth; Chung, Wendy; John, Esther M; Southey, Melissa; Goldgar, David; Singer, Christian F; Maria, Muy-Kheng Tea; Gschwantler-Kaulich, Daphne; Fink-Retter, Anneliese; Hansen, Thomas v. O.; Ejlertsen, Bent; Johannsson, Oskar Th.; Offit, Kenneth; Sarrel, Kara; Gaudet, Mia M.; Vijai, Joseph; Robson, Mark; Piedmonte, Marion R; Andrews, Lesley; Cohn, David; DeMars, Leslie R.; DiSilvestro, Paul; Rodriguez, Gustavo; Toland, Amanda Ewart; Montagna, Marco; Agata, Simona; Imyanitov, Evgeny; Isaacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Ramus, Susan J; Sucheston, Lara; Karlan, Beth Y.; Gross, Jenny; Ganz, Patricia A.; Beattie, Mary S.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Meindl, Alfons; Arnold, Norbert; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorotehea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Nevanlinna, Heli; Aittomäki, Kristiina; Simard, Jacques; Spurdle, Amanda B.; Beesley, Jonathan; Chen, Xiaoqing; Tomlinson, Gail E.; Weitzel, Jeffrey; Garber, Judy E.; Olopade, Olufunmilayo I.; Rubinstein, Wendy S.; Tung, Nadine; Blum, Joanne L.; Narod, Steven A.; Brummel, Sean; Gillen, Daniel L.; Lindor, Noralane; Fredericksen, Zachary; Pankratz, Vernon S.; Couch, Fergus J.; Radice, Paolo; Peterlongo, Paolo; Greene, Mark H.; Loud, Jennifer T.; Mai, Phuong L.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Gerdes, Anne-Marie; Thomassen, Mads; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A.; Lee, Andrew; Chenevix-Trench, Georgia; Antoniou, Antonis C; Neuhausen, Susan L.

    2012-01-01

    Background We previously reported significant associations between genetic variants in insulin receptor substrate 1 (IRS1) and breast cancer risk in women carrying BRCA1 mutations. The objectives of this study were to investigate whether the IRS1 variants modified ovarian cancer risk and were associated with breast cancer risk in a larger cohort of BRCA1 and BRCA2 mutation carriers. Methods IRS1 rs1801123, rs1330645, and rs1801278 were genotyped in samples from 36 centers in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analyzed by a retrospective cohort approach modeling the associations with breast and ovarian cancer risks simultaneously. Analyses were stratified by BRCA1 and BRCA2 status and mutation class in BRCA1 carriers. Results Rs1801278 (Gly972Arg) was associated with ovarian cancer risk for both BRCA1 [Hazard ratio (HR) = 1.43; 95% CI: 1.06–1.92; p = 0.019] and BRCA2 mutation carriers (HR=2.21; 95% CI: 1.39–3.52, p=0.0008). For BRCA1 mutation carriers, the breast cancer risk was higher in carriers with class 2 mutations than class 1 (mutations (class 2 HR=1.86, 95% CI: 1.28–2.70; class 1 HR=0.86, 95%CI:0.69–1.09; p-for difference=0.0006). Rs13306465 was associated with ovarian cancer risk in BRCA1 class 2 mutation carriers (HR = 2.42; p = 0.03). Conclusion The IRS1 Gly972Arg SNP, which affects insulin-like growth factor and insulin signaling, modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers and breast cancer risk in BRCA1 class 2 mutation carriers. Impact These findings may prove useful for risk prediction for breast and ovarian cancers in BRCA1 and BRCA2 mutation carriers. PMID:22729394

  12. 40 CFR 86.1816-18 - Emission standards for heavy-duty vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards for NMOG+NOX Model Year Class 2b Class 3 2016 1 0.333 0.548 2017 1 0.310 0.508 2018 0.278 0.451... for 2016 and 2017 for purposes of voluntary early compliance as described in paragraph (b)(11) of this... voluntarily certify your vehicles under this section in model years 2016 and 2017. If you do this, the...

  13. Latent Class Analysis of Differential Item Functioning on the Peabody Picture Vocabulary Test-III

    ERIC Educational Resources Information Center

    Webb, Mi-young Lee; Cohen, Allan S.; Schwanenflugel, Paula J.

    2008-01-01

    This study investigated the use of latent class analysis for the detection of differences in item functioning on the Peabody Picture Vocabulary Test-Third Edition (PPVT-III). A two-class solution for a latent class model appeared to be defined in part by ability because Class 1 was lower in ability than Class 2 on both the PPVT-III and the…

  14. Molecular evolution of plant haemoglobin: two haemoglobin genes in Nymphaeaceae Euryale ferox.

    PubMed

    Guldner, E; Desmarais, E; Galtier, N; Godelle, B

    2004-01-01

    We isolated and sequenced two haemoglobin genes from the early-branching angiosperm Euryale ferox (Nymphaeaceae). The two genes belong to the two known classes of plant haemoglobin. Their existence in Nymphaeaceae supports the theory that class 1 haemoglobin was ancestrally present in all angiosperms, and is evidence for class 2 haemoglobin being widely distributed. These sequences allowed us to unambiguously root the angiosperm haemoglobin phylogeny, and to corroborate the hypothesis that the class 1/class 2 duplication event occurred before the divergence between monocots and eudicots. We addressed the molecular evolution of plant haemoglobin by comparing the synonymous and nonsynonymous substitution rates in various groups of genes. Class 2 haemoglobin genes of legumes (functionally involved in a symbiosis with nitrogen-fixing bacteria) show a higher nonsynonymous substitution rate than class 1 (nonsymbiotic) haemoglobin genes. This suggests that a change in the selective forces applying to plant haemoglobins has occurred during the evolutionary history of this gene family, potentially in relation with the evolution of symbiosis.

  15. Rate of promoter class turn-over in yeast evolution

    PubMed Central

    Bazykin, Georgii A; Kondrashov, Alexey S

    2006-01-01

    Background Phylogenetic conservation at the DNA level is routinely used as evidence of molecular function, under the assumption that locations and sequences of functional DNA segments remain invariant in evolution. In particular, short DNA segments participating in initiation and regulation of transcription are often conserved between related species. However, transcription of a gene can evolve, and this evolution may involve changes of even such conservative DNA segments. Genes of yeast Saccharomyces have promoters of two classes, class 1 (TATA-containing) and class 2 (non-TATA-containing). Results Comparison of upstream non-coding regions of orthologous genes from the five species of Saccharomyces sensu stricto group shows that among 212 genes which very likely have class 1 promoters in S. cerevisiae, 17 probably have class 2 promoters in one or more other species. Conversely, among 322 genes which very likely have class 2 promoters in S. cerevisiae, 44 probably have class 1 promoters in one or more other species. Also, for at least 2 genes from the set of 212 S. cerevisiae genes with class 1 promoters, the locations of the TATA consensus sequences are substantially different between the species. Conclusion Our results indicate that, in the course of yeast evolution, a promoter switches its class with the probability at least ~0.1 per time required for the accumulation of one nucleotide substitution at a non-coding site. Thus, key sequences involved in initiation of transcription evolve with substantial rates in yeast. PMID:16472383

  16. Diversity of Food Allergy.

    PubMed

    Moriyama, Tatsuya

    2015-01-01

    Food allergy is defined as an immune system-mediated adverse reaction to food components. Food allergic reactions are mostly IgE mediated and also known as immediate type hypersensitivity (type I reaction). There are several characteristic clinical types of food allergy, such as Anaphylaxis, Food-dependent exercise-induced anaphylaxis (FDEIA), and Oral allergy syndrome (OAS). In addition, food allergy is also classified into two types (class 1 and class 2) based on the pathophysiological mechanism. In the class 2 food allergy, pollen allergy causes plant food allergy; therefore this type of allergy is sometimes called Pollen-food allergy syndrome (PFAS). The risk of food allergy (allergenicity) may vary with the treatment of the food allergens. The formation or status of the causative food affects its allergenicity. Class 1 food allergens are generally heat-, enzyme-, and low pH-resistant glycoproteins ranging in size from 10 to 70 kD. Class 1 food allergens induce allergic sensitization via the gastrointestinal tract and are responsible for systemic reactions. Class 2 food allergens are generally heat-labile, susceptible to digestion, and highly homologous with pollen allergens. Taken together, it may be important to consider the diversity of food allergy in order to fight against food allergy.

  17. Influence of Horse and Rider on Stress during Horse-riding Lesson Program

    PubMed Central

    Kang, Ok-Deuk; Yun, Young-Min

    2016-01-01

    The present study aims to confirm the influence of a horse-riding lesson program (HRLP) on the stress level of horses and riders by respectively analyzing their salivary cortisol concentration. Twenty-four healthy horses and 23 riders participated in this study. The horses were randomly classified into two groups for the horse riding lesson program: Class 1 (for the beginner lesson) and Class 2 (for the intermediate lesson). The Class 1 group consisted of 12 horses and 12 riders, while the Class 2 group consisted of 12 horses and 11 riders. Salivettes cotton wool swabs were used for saliva collection and the saliva analyses were conducted using a two-way analysis of variance for repeated measures with SAS version 8. As for the results, the average salivary cortisol concentration of all horses before HRLP significantly increased compared to the baseline (p<0.001) while it decreased after the HRLP. The results of the salivary cortisol concentration of the riders were similar to the horses’ results. However, there was no difference during the HRLP between Class 1 and Class 2 in the horse or rider groups. The results suggest that the HRLP did not influence the stress level of the horses or riders. Thus, this study provides the necessary information and guidelines for future studies on stress in horses during riding and gives insight into better horse welfare and management options. PMID:27004819

  18. Line formation in Be star envelopes. II. Disk oscillations.

    NASA Astrophysics Data System (ADS)

    Hummel, W.; Hanuschik, R. W.

    1997-04-01

    We present numerical model calculations for an especially interesting class of Hα emission line profiles from Be star disks, those with asymmetric shape and long-term variability (so-called class 2 profiles). As an underlying model for the disk we investigate the hypothesis of Okazaki (1997A&A...318..548O) that these profiles are caused by a distortion of a quasi-Keplerian disk. The distortion has the form of a one-armed global disk oscillation (density and velocity wave). The radiation transfer in the disk is calculated with an improved version of the spatially implicit 3D radiative transfer code of Hummel (1994). The resulting sets of Hα emission line profiles reproduce well the observed structures of fully-resolved class 2 Hα emission lines, like double peaks and winebottle-type shoulders. For high inclinations, shell-type profiles result. It is shown that the full variety of observed profile shapes is caused by the interaction of kinematical and non-coherent scattering broadening. While this result has already been found by Hummel (1994) for the symmetric (class 1) Hα profiles, it is proven here for the second major profile class as well. The comparison between observed and theoretical emission shows that the model of global disk oscillations is in full agreement with the observed shapes and the cyclic long-term variability of class 2 profiles.

  19. Advanced powder metallurgy aluminum alloys via rapid solidification technology, phase 2

    NASA Technical Reports Server (NTRS)

    Ray, Ranjan; Jha, Sunil C.

    1987-01-01

    Marko's rapid solidification technology was applied to processing high strength aluminum alloys. Four classes of alloys, namely, Al-Li based (class 1), 2124 type (class 2), high temperature Al-Fe-Mo (class 3), and PM X7091 type (class 4) alloy, were produced as melt-spun ribbons. The ribbons were pulverized, cold compacted, hot-degassed, and consolidated through single or double stage extrusion. The mechanical properties of all four classes of alloys were measured at room and elevated temperatures and their microstructures were investigated optically and through electron microscopy. The microstructure of class 1 Al-Li-Mg alloy was predominantly unrecrystallized due to Zr addition. Yield strengths to the order of 50 Ksi were obtained, but tensile elongation in most cases remained below 2 percent. The class 2 alloys were modified composition of 2124 aluminum alloy, through addition of 0.6 weight percent Zr and 1 weight percent Ni. Nickel addition gave rise to a fine dispersion of intermetallic particles resisting coarsening during elevated temperature exposure. The class 2 alloy showed good combination of tensile strength and ductility and retained high strength after 1000 hour exposure at 177 C. The class 3 Al-Fe-Mo alloy showed high strength and good ductility both at room and high temperatures. The yield and tensile strength of class 4 alloy exceeded those of the commercial 7075 aluminum alloy.

  20. The Effects of Cumulative Victimization on Mental Health Among Lesbian, Gay, Bisexual, and Transgender Adolescents and Young Adults

    PubMed Central

    Andrews, Rebecca; Puckett, Jae A.

    2016-01-01

    Objectives. To examine the effects of the cumulative victimization experienced by lesbian, gay, bisexual, and transgender youths on mental disorders. Methods. We recruited 248 participants from the Chicago, Illinois, area in 7 waves of data collected over 4 years, beginning in 2007 (83.1% retention rate). Mean age at enrollment was 18.7 years, and 54.7% were Black. We measured depression and posttraumatic stress disorder using structured psychiatric interviews. Results. Latent class analyses of victimization over time identified a 4-class solution. Class 1 (65.4%) had low, decreasing victimization. Class 2 (10.3%) had moderate, increasing victimization. Class 3 (5.1%) had high, steady victimization. Class 4 (19.2%) had high, decreasing victimization. Controlling for baseline diagnoses and birth sex, lesbian, gay, bisexual, and transgender youths in classes 2 and 3 were at higher risk for depression than were those in class 1; youths in classes 2, 3, and 4 were at elevated risk for posttraumatic stress disorder. Conclusions. Lesbian, gay, bisexual, and transgender youths with steadily high or increasing levels of victimization from adolescence to early adulthood are at higher risk for depression and posttraumatic stress disorder. PMID:26794175

  1. Technical criteria for an Area-Of-Review variance methodology. Appendix B

    SciTech Connect

    1994-01-01

    This guidance was developed by the Underground Injection Practices Research Foundation to assist Underground Injection Control Directors in implementing proposed changes to EPA`s Class 2 Injection Well Regulations that will apply the Area-Of-Review (AOR) requirement to previously exempt wells. EPA plans to propose amendments this year consistent with the recommendations in the March 23, 1992, Final Document developed by the Class 2 Injection Well Advisory Committee, that will require AORs to be performed on all Class 2 injection wells except those covered by previously conducted AORs and those located in areas that have been granted a variance. Variances may be granted if the Director determines that there is a sufficiently low risk of upward fluid movement from the injection zone that could endanger underground sources of drinking water. This guidance contains suggested technical criteria for identifying areas eligible for an AOR variance. The suggested criteria were developed in consultation with interested States and representatives from EPA, industry and the academic community. Directors will have six months from the promulgation of the new regulations to provide EPA with either a schedule for performing AOR`s within five years on all wells not covered by previously conducted AORs, or notice of their intent to establish a variance program. It is believed this document will provide valuable assistance to Directors who are considering whether to establish a variance program or have begun early preparations to develop such a program.

  2. Integrons, β-lactamase and qnr genes in multidrug resistant clinical isolates of Proteus mirabilis and P. vulgaris.

    PubMed

    Mokracka, Joanna; Gruszczyńska, Beata; Kaznowski, Adam

    2012-12-01

    Thirty-three isolates of Proteus mirabilis and two P. vulgaris were examined for their antimicrobial resistance, the presence of integrons with regard to gene cassette content, and genetic determinants of β-lactam and low-level quinolone resistance. Integrons were detected in 23 (69.7%) P. mirabilis isolates; six (18.2%) of them had class 1 integrons, 11 (33.3%) possessed class 2 integrons and six (18.2%) carried integrons of both classes. One P. vulgaris strain possessed class 1 and class 2 integrons. The presence of integrons was associated with increased frequency of resistance to gentamicin, ciprofloxacin, sulfamethoxazole and co-trimoxazole. Moreover, integron presence was associated with increased resistance range in terms of both the number of antimicrobials and the number of classes of antimicrobials to which a strain was resistant. Class 1 integrons contained aadA1, aadB-aadA1, dfrA1-aadA1, bla(PSE-1) -aadA1 and aacA4-orfA-orfB-aadA1 gene cassette arrays, whereas all class 2 integrons had a dfrA1-sat2-aada1 array. β-lactamase genes not associated with integrons comprised bla(TEM-2) , bla(DHA-1) and bla(CMY-15) . Plasmid-mediated fluoroquinolone resistance was determined by qnrD and qnrS1 genes. This is the first report of P. vulgaris strains harbouring qnrD genes in Europe.

  3. Prognostic Implications of Tumor Diameter in Association With Gene Expression Profile for Uveal Melanoma

    PubMed Central

    Walter, Scott D.; Chao, Daniel L.; Feuer, William; Schiffman, Joyce; Char, Devron H.; Harbour, J. William

    2016-01-01

    IMPORTANCE Uveal melanoma (UM) can be divided into prognostically significant subgroups based on a prospectively validated and widely used 15-gene expression profile (GEP) test. Class 1 UMs have a low risk and class 2 UMs have a high risk for metastasis. OBJECTIVE To determine whether any clinicopathologic factors provide independent prognostic information that may enhance the accuracy of the GEP classification. DESIGN, SETTING, AND PARTICIPANTS This retrospective observational study performed at 2 ocular oncology referral centers included 339 patients in a primary cohort and 241 patients in a validation cohort. Both cohorts had a diagnosis of UM arising from the ciliary body and/or choroid. All patients underwent tumor biopsy for GEP prognostic testing. Clinicopathologic variables included patient age and sex, tumor thickness, largest basal tumor diameter (LBD), ciliary body involvement, and pathologic cell type. Patients from the primary cohort were enrolled from November 1, 1998, to March 16, 2012; from the validation cohort, from November 4, 1996, to November 7, 2013. Follow-up for the primary cohort was completed on August 18, 2013; for the validation cohort, December 10, 2013. Data were analyzed from November 12, 2013, to November 25, 2015. MAIN OUTCOME AND MEASURES Progression-free survival (PFS). The secondary outcome was overall survival. RESULTS The primary cohort included 339 patients (175 women [51.6%]; mean [SD] age, 61.8 [13.6] years). The most significant prognostic factor was GEP classification (exp[b], 10.33; 95% CI, 4.30–24.84; P < .001). The only other variable that provided independent prognostic information was LBD (exp[b], 1.13; 95% CI, 1.02–1.26; P = .02). Among class 2 UMs, LBD showed a modest but significant association with PFS (exp[b], 1.13; 95% CI, 1.04–1.24; P = .005). The 5-year actuarial metastasis-free survival estimates (SE) were 97% (3%) for class 1 UMs with LBD of less than 12 mm, 90% (4%) for class 1 UMs with LBD of at

  4. [Mode of splitting of the second heart sound in patients with hypertrophic cardiomyopathy].

    PubMed

    Fukuda, N; Oki, T; Sakai, H; Asai, M; Ohshima, C; Kusaka, Y; Tominaga, T; Murao, A; Niki, T; Mori, H

    1983-06-01

    pts with resting type of HOCM showed a long (Q-IIA)c due to the prolongation of LVETc, but latent type showed the same change as in HCM. c) The pts with HT showed a tendency of prolongation of (Q-IIA)c due to slightly short LVETc and long corrected pre-ejection period (PEPc). Fractional shortening of the left ventricle (%FS) and mean velocity of circumferential fiber shortening (mean VCF) calculated from echocardiograms were significantly greater in both types of HCM than those in normals and HT (p less than 0.05). Left ventricular end-diastolic dimension was significantly decreased in the pts with septal hypertrophic type of HCM than in others.(ABSTRACT TRUNCATED AT 400 WORDS)

  5. Latent Classes of Course in Alzheimer’s Disease and Predictors: The Cache County Dementia ProgressionStudy

    PubMed Central

    Leoutsakos, J.S.; Forrester, S.N.; Corcoran, C.D.; Norton, M.C.; Rabins, Peter V.; Steinberg, Martin I.; Tschanz, J.T.; Lyketsos, C.G.

    2015-01-01

    Objective Several longitudinal studies of Alzheimer Disease (AD) report heterogeneity in progression. We sought to identify groups (classes) of progression-trajectories in the population-based Cache County Dementia Progression Study (N=328), and to identify baseline predictors of membership for each group. Methods We used parallel-process growth mixture models (GMM) to identify latent classes of trajectories based on MMSE and CDR-sb scores over time. We then used bias-corrected multinomial logistic regression to model baseline predictors of latent class membership. We constructed ROC curves to demonstrate relative predictive utility of successive sets of predictors. Results We fit 4 latent classes; class 1 was the largest (72%), and had the slowest progression. Classes 2 (8%) ,3 (11%), and 4 (8%) had more rapid worsening. In univariate analyses, longer dementia duration, presence of psychosis, and worse baseline MMSE and CDR-sb were associated with membership in class 2, relative to class 1. Lower education was associated with membership in class 3. In the multivariate model, only MMSE remained a statistically significant predictor of class membership. ROC AUCs were 0.98, 0.88, and 0.67, for classes 2,3, and 4 relative to class 1. Conclusions Heterogeneity in AD course can be usefully characterized using GMM. The majority belonged to a class characterized by slower decline than is typically reported in clinical samples. Class membership could be predicted using baseline covariates. Further study may advance our prediction of AD course at the population level, and in turn shed light on the pathophysiology of progression. PMID:25363393

  6. Patterns of Violence Against Women: A Latent Class Analysis

    PubMed Central

    Cavanaugh, Courtenay E.; Messing, Jill T.; Petras, Hanno; Fowler, Barbara; La Flair, Lareina; Kub, Joan; Agnew, Jacqueline; Fitzgerald, Sheila; Bolyard, Richelle; Campbell, Jacquelyn C.

    2012-01-01

    This study examined patterns of nine types of violence against women (VAW) and associated mental health problems. The following self-reported, lifetime violence victimization was examined among 1424 employed women: (1) childhood physical abuse, (2) childhood sexual abuse, (3) physical abuse between parents/guardians during childhood, (4) psychological intimate partner violence (IPV), (5) physical IPV, (6) sexual IPV, (7) adult physical or sexual assault by a non-intimate partner, (8) physical workplace violence, and (9) psychological workplace violence. Latent class analysis was used to identify homogenous patterns, called “classes,” of women's “yes/no” responses to experiencing these types of violence. The best model consisted of 4-classes characterized by the following probabilities: low violence (class 1: 63.1%), high psychological and physical IPV (class 2: 15.6%), high physical and psychological workplace violence (class 3: 12.4%), and moderate to high childhood abuse (class 4: 9.0%). When compared to class 1 (low violence), membership in classes 2 (IPV) and 4 (childhood abuse) was associated with screening positive for depression in the past week at baseline after controlling for the influence of demographic characteristics on class membership. Also, when compared to class 1 (low all), membership in class 2 (IPV) was associated with greater odds of screening positive for posttraumatic stress disorder in the past month at the six month follow-up assessment. Findings document distinct patterns of VAW and associated proximal and distal mental health outcomes. Implications for interventions aimed to improve employed women's health are discussed. PMID:22662284

  7. Gender roles and binge drinking among Latino emerging adults: a latent class regression analysis.

    PubMed

    Vaughan, Ellen L; Wong, Y Joel; Middendorf, Katharine G

    2014-09-01

    Gender roles are often cited as a culturally specific predictor of drinking among Latino populations. This study used latent class regression to test the relationships between gender roles and binge drinking in a sample of Latino emerging adults. Participants were Latino emerging adults who participated in Wave III of the National Longitudinal Study of Adolescent Health (N = 2,442). A subsample of these participants (n = 660) completed the Bem Sex Role Inventory--Short. We conducted latent class regression using 3 dimensions of gender roles (femininity, social masculinity, and personal masculinity) to predict binge drinking. Results indicated a 3-class solution. In Class 1, the protective personal masculinity class, personal masculinity (e.g., being a leader, defending one's own beliefs) was associated with a reduction in the odds of binge drinking. In Class 2, the nonsignificant class, gender roles were not related to binge drinking. In Class 3, the mixed masculinity class, personal masculinity was associated with a reduction in the odds of binge drinking, whereas social masculinity (e.g., forceful, dominant) was associated with an increase in the odds of binge drinking. Post hoc analyses found that females, those born outside the United States, and those with greater English language usage were at greater odds of being in Class 1 (vs. Class 2). Males, those born outside the United States, and those with greater Spanish language usage were at greater odds of being in Class 3 (vs. Class 2). Directions for future research and implications for practice with Latino emerging adults are discussed.

  8. The Effect of ACP₁-ADA₁ Genetic Interaction on Human Life Span.

    PubMed

    Lucarini, Nazzareno; Napolioni, Valerio; Magrini, Andrea; Gloria, Fulvia

    2012-12-01

    Acid phosphatase (ACP₁) is a polymorphic enzyme that catalyzes the conversion of flavin-mononucleotide (FMN) to riboflavin and regulates the cellular concentration of flavin-adenine-dinucleotide (FAD) and, consequently, energy metabolism. Its activity is modulated by adenosine deaminase locus 1 (ADA₁) genotype. The aim of our work is to verify whether individuals with a high proportion of ACP₁ f-isozyme and carrying the ADA₁*2 allele, displaying the highest phosphatase activity, may have a higher life expectancy. Genomic DNA was extracted from the peripheral blood of 569 females and 509 males (18 to 106 years of age) randomly recruited from Central Italy. These samples were subdivided into three sex-specific age groups (the ages of women are in square bracket): Class 1: age <66 [<73]; Class 2: ages 66 to 88 [73 to 91]; Class 3: age >88 [>91]. ACP₁and ADA₁ singlenucleotide polymorphisms (SNPs) were genotyped by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods and statistical analyses were performed with SPSS 14.0. The results showed a larger proportion of Class 3 individuals displaying high ACP₁ f-isozyme concentration and carrying the ADA₁*2 allele than those individuals of Class 2 and Class 2 plus Class 1. Thus, we postulate that in Class 3 individuals the high phosphatase activity, resulting from the combined presence of high ACP₁ f-isozyme concentration and the ADA₁*2 allele, lowers the rate of glycolysis that may reduce the amount of metabolic calories and, in turn, activate Sirtuin genes that protect cells against age-related diseases.

  9. Forest health status in the Carpathian Mountains over the period 1997-2001.

    PubMed

    Badea, Ovidiu; Tanase, Mihai; Georgeta, Jianu; Anisoara, Lazar; Peiov, Agata; Uhlirova, Hana; Pajtik, Josef; Wawrzoniak, Jerzy; Shparyk, Yuri

    2004-07-01

    The results of forest health status assessments in the Carpathian Mountains from the monitoring networks developed by the European Union Scheme on the Protection of Forest Against Atmospheric Pollution (EU Scheme) and International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP-Forests), have led to a better understanding of the impact of air pollution and other stressors on forests at the regional scale. During the period 1997-2001, forests in the Carpathian Mountains were severely affected by air pollution and natural stresses with 29.7-34.9% of the trees included in defoliation classes 2-4. The broadleaves were slightly healthier than the conifers, and European beech (Fagus sylvatica) was the least affected species. Norway spruce (Picea abies) has poor health status, with 42.9-46.6% of the trees damaged (2-4% defoliation classes). Silver fir (Abies alba) damage was also high, with 46.0-50.9% in defoliation classes 2-4. Pines (primarily Pinus sylvestris) were the least affected of the conifers, with 24.9-33.8% in defoliation classes 2-4. The results from the transnational networks (16 x 16 km) show that the Carpathian forests are slightly more damaged than the average for the entire Europe. The correlative studies performed in individual European countries show the relationships between air pollution stressors with trends in defoliation and a possible effect of natural stresses at each site. More specific, effects of tree age, drought, ozone and acid deposition critical level exceedances were demonstrated to affect crown condition.

  10. Healing ulcers and preventing their recurrences in the diabetic foot

    PubMed Central

    Sabapathy, S. Raja; Periasamy, Madhu

    2016-01-01

    Fifteen percent of people with diabetes develop an ulcer in the course of their lifetime. Eighty-five percent of the major amputations in diabetes mellitus are preceded by an ulcer. Management of ulcers and preventing their recurrence is important for the quality of life of the individual and reducing the cost of care of treatment. The main causative factors of ulceration are neuropathy, vasculopathy and limited joint mobility. Altered bio-mechanics due to the deformities secondary to neuropathy and limited joint mobility leads to focal points of increased pressure, which compromises circulation leading to ulcers. Ulcer management must not only address the healing of ulcers but also should correct the altered bio-mechanics to reduce the focal pressure points and prevent recurrence. An analysis of 700 patients presenting with foot problems to the Diabetic Clinic of Ganga Hospital led to the stratification of these patients into four classes of incremental severity. Class 1 – the foot at risk, Class 2 – superficial ulcers without infection, Class 3 – the crippled foot and Class 4 – the critical foot. Almost 77.5% presented in either Class 3 or 4 with complicated foot ulcers requiring major reconstruction or amputation. Class 1 foot can be managed conservatively with foot care and appropriate foot wear. Class 2 in addition to measures for ulcer healing would need surgery to correct the altered bio-mechanics to prevent the recurrence. The procedures called surgical offloading would depend on the site of the ulcer and would need an in-depth clinical study of the foot. Class 3 would need major reconstructive procedures and Class 4 would need amputation since it may be life-threatening. As clinicians, our main efforts must be focused towards identifying patients in Class 1 and offer advice on foot care and Class 2 where appropriate surgical offloading procedure would help preserve the foot. PMID:28216809

  11. Isolation and molecular characterization of multidrug-resistant strains of Escherichia coli and Salmonella from retail chicken meat in Japan.

    PubMed

    Ahmed, Ashraf M; Shimabukuro, Hirofumi; Shimamoto, Tadashi

    2009-09-01

    Sixty-nine Escherichia coli and 10 Salmonella isolates, recovered from retail chicken meat in Hiroshima prefecture, Japan, were assayed for antimicrobial susceptibility, the presence of integrons and antimicrobial resistance genes. Twenty-eight out of 69 (40.6%) of E. coli and all 10 Salmonella isolates were exhibited multidrug resistance phenotypes. The most commonly reported resistance phenotypes were against ampicillin, streptomycin, spectinomycin, kanamycin, tetracycline, and trimethoprim/sulfamethoxazole. PCR screening for integrons showed that 8 (11.6%) of the E. coli isolates were positive for the class 1 integrons and 1 isolate (1.4%) was positive for the class 2 integrons. Among the 10 Salmonella isolates, 9 were positive for class 1 integrons and none was positive for class 2 integrons. The identified antibiotic resistance gene cassettes within the class 1 integrons were dfrA1, dfrA7, aadA1, aadB, and catB3, while dfrA1, sat2, and aadA1 were identified within class 2 integron. The beta-lactamase resistance gene bla(TEM-1) was identified in 12 (17.3%) of E. coli isolates and in only one of the Salmonella isolates. The bla(CMY-2) gene, encoding AmpC beta-lactamase, was detected in 16 (23.2%) of the E. coli isolates only. Conjugation experiments demonstrated that there was plasmid-mediated transfer of bla(CMY-2) and bla(TEM-1). These results highlighted the role of retail chicken meat as a potential source for multidrug-resistant strains of E. coli and Salmonella. To the best of our knowledge, this is the 1st report of isolation and molecular characterization of multidrug-resistant strains of E. coli from retail chicken meat in Japan.

  12. The solar wind structures associated with cosmic ray decreases and particle acceleration in 1978-1982

    NASA Technical Reports Server (NTRS)

    Cane, H. V.; Richardson, I. G.; Vonrosenvinge, T. T.

    1992-01-01

    The time histories of particles in the energy range 1 MeV to 1 GeV at times of all greater than 3 percent cosmic ray decreases in the years 1978 to 1982 are studied. Essentially all 59 of the decreases commenced at or before the passages of interplanetary shocks, the majority of which accelerated energetic particles. We use the intensity-time profiles of the energetic particles to separate the cosmic ray decreases into four classes which we subsequently associate with four types of solar wind structures. Decreases in class 1 (15 events) and class 2 (26 events) can be associated with shocks which are driven by energetic coronal mass ejections. For class 1 events the ejecta is detected at 1 AU whereas this is not the case for class 2 events. The shock must therefore play a dominant role in producing the depression of cosmic rays in class 2 events. In all class 1 and 2 events (which comprise 69 percent of the total) the departure time of the ejection from the sun (and hence the location) can be determined from the rapid onset of energetic particles several days before the shock passage at Earth. The class 1 events originate from within 50 deg of central meridian. Class 3 events (10 decreases) can be attributed to less energetic ejections which are directed towards the Earth. In these events the ejecta is more important than the shock in causing a depression in the cosmic ray intensity. The remaining events (14 percent of the total) can be attributed to corotating streams which have ejecta material embedded in them.

  13. Evaluation of the Gas Production Potential of Marine HydrateDeposits in the Ulleung Basin of the Korean East Sea

    SciTech Connect

    Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol,Yongkoo; Zhang, Keni

    2007-11-16

    Although significant hydrate deposits are known to exist in the Ulleung Basin of the Korean East Sea, their survey and evaluation as a possible energy resource has not yet been completed. However, it is possible to develop preliminary estimates of their production potential based on the limited data that are currently available. These include the elevation and thickness of the Hydrate-Bearing Layer (HBL), the water depth, and the water temperature at the sea floor. Based on this information, we developed estimates of the local geothermal gradient that bracket its true value. Reasonable estimates of the initial pressure distribution in the HBL can be obtained because it follows closely the hydrostatic. Other critical information needs include the hydrate saturation, and the intrinsic permeabilities of the system formations. These are treated as variables, and sensitivity analysis provides an estimate of their effect on production. Based on the geology of similar deposits, it is unlikely that Ulleung Basin accumulations belong to Class 1 (involving a HBL underlain by a mobile gas zone). If Class 4 (disperse, low saturation accumulations) deposits are involved, they are not likely to have production potential. The most likely scenarios include Class 2 (HBL underlain by a zone of mobile water) or Class 3 (involving only an HBL) accumulations. Assuming nearly impermeable confining boundaries, this numerical study indicates that large production rates (several MMSCFD) are attainable from both Class 2 and Class 3 deposits using conventional technology. The sensitivity analysis demonstrates the dependence of production on the well design, the production rate, the intrinsic permeability of the HBL, the initial pressure, temperature and hydrate saturation, as well as on the thickness of the water zone (Class 2). The study also demonstrates that the presence of confining boundaries is indispensable for the commercially viable production of gas from these deposits.

  14. Urinary excretion of the acrylonitrile metabolite 2-cyanoethylmercapturic acid is correlated with a variety of biomarkers of tobacco smoke exposure and consumption.

    PubMed

    Minet, Emmanuel; Cheung, Francis; Errington, Graham; Sterz, Katharina; Scherer, Gerhard

    2011-02-01

    Acrylonitrile is an IARC class 2B carcinogen present in cigarette smoke. Urinary 2-cyanoethylmercapturic acid (CEMA) is an acrylonitrile metabolite and a potential biomarker for acrylonitrile exposure. The objective of this work was to study the dose response of CEMA in urine of non-smokers and smokers of different ISO tar yield cigarettes. We observed that smokers excreted >100-fold higher amounts of urinary CEMA than non-smokers. The CEMA levels in smokers were significantly correlated with ISO tar yield, daily cigarette consumption, and urinary biomarkers of smoke exposure. In conclusion, urinary CEMA is a suitable biomarker for assessing smoking-related exposure to acrylonitrile.

  15. Maskelynite formation via solid-state transformation: Evidence of infrared and x-ray anisotropy

    SciTech Connect

    Jaret, Steven J.; Ehm, Lars; Woerner, William R.; Phillips, Brian L.; Nekvasil, Hanna; Wright, Shawn P.; Glotch, Timothy D.

    2015-03-24

    We present optical microscopy, micro-Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, high-energy X-ray total scattering experiments, and micro-Fourier transform infrared (micro-FTIR) spectroscopy on shocked labradorite from the Lonar Crater, India. We show that maskelynite of shock class 2 is structurally more similar to fused glass than to crystalline plagioclase. However, there are slight but significant differences – preservation of original pre-impact igneous zoning, anisotropy at Infrared wavelengths, X-ray anisotropy, and preservation of some intermediate range order – which are all consistent with a solid-state transformation formation of maskelynite.

  16. Unusual mixed valent FeIIIFeII complex (St = 3/2) stabilised by a reduced bulky 1,2-diketone.

    PubMed

    Spikes, Geoffrey H; Bill, Eckhard; Weyhermüller, Thomas; Wieghardt, Karl

    2007-11-14

    The reduction of the bulky 1,2-diketone bis(2,6-diisopropylphenyl)glyoxal () and FeBr(2) with 1.5 equivalents of Na results in a Class 2 mixed valent H.S. Fe(II) L.S. Fe(III) complex (2) with two five-coordinate Fe centres which are antiferromagnetically exchange-coupled to give a total spin S(t) = 3/2 ground state and an S(t) = 5/2 excited state that are separated by about 25 cm(-1) (for Delta(J) approximately 5J).

  17. Fuel comsumption of heavy-duty trucks : potential effect of future technologies for improving energy efficiency and emission.

    SciTech Connect

    Saricks, C. L.; Vyas, A. D.; Stodolsky, F.; Maples, J. D.; Energy Systems; USDOE

    2003-01-01

    The results of an analysis of heavy-duty truck (Classes 2b through 8) technologies conducted to support the Energy Information Administration's long-term projections for energy use are summarized. Several technology options that have the potential to improve the fuel economy and emissions characteristics of heavy-duty trucks are included in the analysis. The technologies are grouped as those that enhance fuel economy and those that improve emissions. Each technology's potential impact on the fuel economy of heavy-duty trucks is estimated. A rough cost projection is also presented. The extent of technology penetration is estimated on the basis of truck data analyses and technical judgment.

  18. The Enlisted Survival Tracking File (STF): A Revision.

    DTIC Science & Technology

    1982-09-01

    37 Rate/Special Program Code 3 38 Branch/Class 2 43 RADO Months 3 45 Enlisted Designator 1 48 Present Rate Code. 4 49 Present Pay Grade 1 .3 PNEC 4 54...262 RADO Months 3 45 155 305 Enlisted Designator 1 48 104 234 Present Rate Code 4 49 56 97 Present Pay Grade 1 53 60 101 PNEC 4 54 86 150 SNEC 4 58 90...data fields have been changed for this individual (e.g., PNEC (positions 54-57), soft EAOS (positions 82-45), onboard UIC (positions 87-91), onboard ACC

  19. Symbiotic lifestyle expression by fungal endophytes and the adaptation of plants to stress: unraveling the complexities of intimacy

    USGS Publications Warehouse

    Redman, Regina S.; Henson, Joan M.; Rodriguez, Russell J.

    2005-01-01

    The fossil record indicates that fungal symbionts have been associated with plants since the Ordovician period (approximately 400 million years ago), when plants first became established on land (Pirozynski and Malloch, 1975; Redecker et al., 2000; Remy et al., 1994; Simon et al., 1993). Transitioning from aquatic to terrestrial habitats likely presented plants with new stresses, including periods of desiccation. Since symbiotic fungi are known to confer drought tolerance to plants (Bacon, 1993; Read and Camp, 1986), it has been suggested that fungal symbiosis was involved with or responsible for the establishment of land plants (Pirozynski and Malloch, 1975). Symbiosis was first defined by De Bary in 1879, and since that time, all plants in natural ecosystems have been found to be colonized with fungal and bacterial symbionts. It is clear that individual plants represent symbiotic communities with microorganisms associated in or on tissues below- and aboveground.There are two major classes of fungal symbionts associated with internal plant tissues: fungal endophytes that reside entirely within plants and may be associated with roots, stems leaves, or flowers; and mycorrhizal fungi that reside only in roots but extend out into the rhizosphere. In addition, fungal endophytes may be divided into two classes: (1) a relatively small number of fastidious species that are limited to a few monocot hosts (Clay and Schardl, 2002), and (2) a large number of tractable species with broad host ranges, including both monocots and eudicots (Stone et al., 2000). While significant resources and research have been invested in mycorrhizae and class 1 endophytes, comparatively little is known about class 2 endophytes, which may represent the largest group of fungal symbionts. This is partially because the symbiotic functionalities of class 2 endophytes have only recently been elucidated and shown to be responsible for the adaptation of some plants to high-stress environments (Redman

  20. Land use studies with Skylab data, August 1974. [Baltimore, Maryland and Washington, D.C.

    NASA Technical Reports Server (NTRS)

    Simonett, D. S. (Principal Investigator); Rohde, W. G.

    1974-01-01

    The author has identified the following significant results. Capabilities of Skylab photographic data suggest significant applications for: (1) identification and mapping of all primary, most secondary, and many tertiary land use classes; (2) stratification of the landscape for more detailed sampling; and (3) rapid updating of existing land use and vegetation maps subscaled at 1:25,000 and smaller with manual interpretation techniques. Automated thematic mapping of land use categories with electronic data processing techniques is feasible with the S-192 multispectral scanner, despite the high noise levels in many channels.

  1. Medical Device Recalls: Examination of Selected Cases

    DTIC Science & Technology

    1989-10-01

    accelerator Device class: 2 Medical specialty: Radiology Brand: Therac - 25 Linear Accelerator Use: Used in clinical (cancer) radiotherapy Premarketing...design recalls.- As wouldl Ne exp~ected, becaulse all (lass 8 (high-risk) dev.ices require prenmarket ap)1O1lmtSt PNMA-dCSigfl r-ecalls ( 25 , or 89...Table 11.4 PMA-Design Recalls by Device Class, Fiscal Years 1983-88 No. oi Device class recalls Percent 2 (medium risk) 3 1 100 3 (high risk) 25 89

  2. Patterns and predictors of violence against children in Uganda: a latent class analysis

    PubMed Central

    Clarke, Kelly; Patalay, Praveetha; Allen, Elizabeth; Knight, Louise; Naker, Dipak; Devries, Karen

    2016-01-01

    Objective To explore patterns of physical, emotional and sexual violence against Ugandan children. Design Latent class and multinomial logistic regression analysis of cross-sectional data. Setting Luwero District, Uganda. Participants In all, 3706 primary 5, 6 and 7 students attending 42 primary schools. Main outcome and measure To measure violence, we used the International Society for the Prevention of Child Abuse and Neglect Child Abuse Screening Tool—Child Institutional. We used the Strengths and Difficulties Questionnaire to assess mental health and administered reading, spelling and maths tests. Results We identified three violence classes. Class 1 (N=696 18.8%) was characterised by emotional and physical violence by parents and relatives, and sexual and emotional abuse by boyfriends, girlfriends and unrelated adults outside school. Class 2 (N=975 26.3%) was characterised by physical, emotional and sexual violence by peers (male and female students). Children in Classes 1 and 2 also had a high probability of exposure to emotional and physical violence by school staff. Class 3 (N=2035 54.9%) was characterised by physical violence by school staff and a lower probability of all other forms of violence compared to Classes 1 and 2. Children in Classes 1 and 2 were more likely to have worked for money (Class 1 Relative Risk Ratio 1.97, 95% CI 1.54 to 2.51; Class 2 1.55, 1.29 to 1.86), been absent from school in the previous week (Class 1 1.31, 1.02 to 1.67; Class 2 1.34, 1.10 to 1.63) and to have more mental health difficulties (Class 1 1.09, 1.07 to 1.11; Class 2 1.11, 1.09 to 1.13) compared to children in Class 3. Female sex (3.44, 2.48 to 4.78) and number of children sharing a sleeping area predicted being in Class 1. Conclusions Childhood violence in Uganda forms distinct patterns, clustered by perpetrator and setting. Research is needed to understand experiences of victimised children, and to develop mental health interventions for those with severe violence

  3. A system approach to archival storage

    NASA Technical Reports Server (NTRS)

    Corcoran, John W.

    1991-01-01

    The introduction and viewgraphs of a discussion on a system approach to archival storage presented at the National Space Science Data Center (NSSDC) Mass Storage Workshop is included. The use of D-2 iron particles for archival storage is discussed along with how acceleration factors relating short-term tests to archival life times can be justified. Ampex Recording Systems is transferring D-2 video technology to data storage applications, and encountering concerns about corrosion. To protect the D-2 standard, Battelle tests were done on all four tapes in the Class 2 environment. Error rates were measured before and after the test on both exposed and control groups.

  4. Urinary excretion of the acrylonitrile metabolite 2-cyanoethylmercapturic acid is correlated with a variety of biomarkers of tobacco smoke exposure and consumption

    PubMed Central

    Minet, Emmanuel; Cheung, Francis; Errington, Graham; Sterz, Katharina; Scherer, Gerhard

    2011-01-01

    Acrylonitrile is an IARC class 2B carcinogen present in cigarette smoke. Urinary 2-cyanoethylmercapturic acid (CEMA) is an acrylonitrile metabolite and a potential biomarker for acrylonitrile exposure. The objective of this work was to study the dose response of CEMA in urine of non-smokers and smokers of different ISO tar yield cigarettes. We observed that smokers excreted >100-fold higher amounts of urinary CEMA than non-smokers. The CEMA levels in smokers were significantly correlated with ISO tar yield, daily cigarette consumption, and urinary biomarkers of smoke exposure. In conclusion, urinary CEMA is a suitable biomarker for assessing smoking-related exposure to acrylonitrile. PMID:21108560

  5. Project W-320, 241-C-106 sluicing: Piping calculations. Volume 2

    SciTech Connect

    Bailey, J.W.

    1998-07-25

    This supporting document has been prepared to make the FDNW calculations for Project W-320 readily retrievable. The objectives of this calculation are (1) To perform static and Safety Class 2 dynamic stress analysis of the Slurry and Supernate Process (inner) piping connecting Tanks 241-C-106 and 241-AY-102 in order to be in compliance with the Code requirements; (2) To assure the thermal expansion of the process pipe not be strained by the outer encasement pipe; and (3) To furnish process pipe support to the Civil Engineering group.

  6. Tropical Cyclone Wind Probability Forecasting for the Eastern North Pacific (EPWINDP).

    DTIC Science & Technology

    1982-04-01

    1 2 3 1 2 3 1 2 3 24 hr 99 130 148 94 97 132 81 99 160 48 hr 204 251 286 176 188 154 200 236 325 72 hr 324 378 407 275 297 393 362 394 477 If we...differences between Classes 1 and 2 ( 24 , 48 and 72 hr ) and then between Classes 2 and 3 for each basin, we obtain the following: Differences: WP diff...4 ~~~ . .... . 4 4. . . . . . 4 . .. .. . . 4 4 . . 4. . .. . 4 . . . . 4 . .. . U.. .: .~: .2.4 . .... . . . . . . . . ..0. . .-1 50 KT 24 Hr 48

  7. Multivariate screening in food adulteration: untargeted versus targeted modelling.

    PubMed

    López, M Isabel; Trullols, Esther; Callao, M Pilar; Ruisánchez, Itziar

    2014-03-15

    Two multivariate screening strategies (untargeted and targeted modelling) have been developed to compare their ability to detect food fraud. As a case study, possible adulteration of hazelnut paste is considered. Two different adulterants were studied, almond paste and chickpea flour. The models were developed from near-infrared (NIR) data coupled with soft independent modelling of class analogy (SIMCA) as a classification technique. Regarding the untargeted strategy, only unadulterated samples were modelled, obtaining 96.3% of correct classification. The prediction of adulterated samples gave errors between 5.5% and 2%. Regarding targeted modelling, two classes were modelled: Class 1 (unadulterated samples) and Class 2 (almond adulterated samples). Samples adulterated with chickpea were predicted to prove its ability to deal with non-modelled adulterants. The results show that samples adulterated with almond were mainly classified in their own class (90.9%) and samples with chickpea were classified in Class 2 (67.3%) or not in any class (30.9%), but no one only as unadulterated.

  8. Profiling Physical Activity, Diet, Screen and Sleep Habits in Portuguese Children

    PubMed Central

    Pereira, Sara; Katzmarzyk, Peter T.; Gomes, Thayse Natacha; Borges, Alessandra; Santos, Daniel; Souza, Michele; dos Santos, Fernanda K.; Chaves, Raquel N.; Champagne, Catherine M.; Barreira, Tiago V.; Maia, José A.R.

    2015-01-01

    Obesity in children is partly due to unhealthy lifestyle behaviours, e.g., sedentary activity and poor dietary choices. This trend has been seen globally. To determine the extent of these behaviours in a Portuguese population of children, 686 children 9.5 to 10.5 years of age were studied. Our aims were to: (1) describe profiles of children’s lifestyle behaviours; (2) identify behaviour pattern classes; and (3) estimate combined effects of individual/socio-demographic characteristics in predicting class membership. Physical activity and sleep time were estimated by 24-h accelerometry. Nutritional habits, screen time and socio-demographics were obtained. Latent Class Analysis was used to determine unhealthy lifestyle behaviours. Logistic regression analysis predicted class membership. About 78% of children had three or more unhealthy lifestyle behaviours, while 0.2% presented no risk. Two classes were identified: Class 1-Sedentary, poorer diet quality; and Class 2-Insufficiently active, better diet quality, 35% and 65% of the population, respectively. More mature children (Odds Ratio (OR) = 6.75; 95%CI = 4.74–10.41), and boys (OR = 3.06; 95% CI = 1.98–4.72) were more likely to be overweight/obese. However, those belonging to Class 2 were less likely to be overweight/obese (OR = 0.60; 95% CI = 0.43–0.84). Maternal education level and household income did not significantly predict weight status (p ≥ 0.05). PMID:26043034

  9. Achromobacter xylosoxidans: an emerging pathogen carrying different elements involved in horizontal genetic transfer.

    PubMed

    Traglia, German Matías; Almuzara, Marisa; Merkier, Andrea Karina; Adams, Christina; Galanternik, Laura; Vay, Carlos; Centrón, Daniela; Ramírez, María Soledad

    2012-12-01

    In the last few years, numerous cases of multidrug-resistant Achromobacter xylosoxidans infections have been documented in immunocompromised and cystic fibrosis patients. To gain insights into the molecular mechanisms and mobile elements related to multidrug resistance in this bacterium, we studied 24 non-epidemiological A. xylosoxidans clinical isolates from Argentina. Specific primers for plasmids, transposons, insertion sequences, bla(ampC), intI1, and intI2 genes were used in PCR reactions. The obtained results showed the presence of wide host range IncP plasmids in ten isolates and a high dispersion of class 1 integrons (n = 10) and class 2 integrons (n = 3). Four arrays in the variable region (vr) of class 1 integrons were identified carrying different gene cassettes as the aminoglycoside resistance aac(6')-Ib and aadA1, the trimethoprim resistance dfrA1 and dfrA16, and the β-lactamase bla(OXA-2). In only one of the class 2 integrons, a vr was amplified that includes sat2-aadA1. The bla(ampC) gene was found in all isolates, confirming its ubiquitous nature. Our results show that A. xylosoxidans clinical isolates contain a rich variety of genetic elements commonly associated with resistance genes and their dissemination. This supports the hypothesis that A. xylosoxidans is becoming a reservoir of horizontal genetic transfer elements commonly involved in spreading antibiotic resistance.

  10. Increased fitness of rice plants to abiotic stress via habitat adapted symbiosis: a strategy for mitigating impacts of climate change.

    PubMed

    Redman, Regina S; Kim, Yong Ok; Woodward, Claire J D A; Greer, Chris; Espino, Luis; Doty, Sharon L; Rodriguez, Rusty J

    2011-01-01

    Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing across moisture and salinity gradients.Plant growth and development, water usage, ROS sensitivity and osmolytes were measured with and without stress under controlled conditions.The endophytes conferred salt, drought and cold tolerance to growth chamber and greenhouse grown plants. Endophytes reduced water consumption by 20-30% and increased growth rate, reproductive yield, and biomass of greenhouse grown plants. In the absence of stress, there was no apparent cost of the endophytes to plants, however, endophyte colonization decreased from 100% at planting to 65% compared to greenhouse plants grown under continual stress (maintained 100% colonization).These findings indicate that rice plants can exhibit enhanced stress tolerance via symbiosis with Class 2 endophytes, and suggest that symbiotic technology may be useful in mitigating impacts of climate change on other crops and expanding agricultural production onto marginal lands.

  11. RF3:GTP promotes rapid dissociation of the class 1 termination factor.

    PubMed

    Koutmou, Kristin S; McDonald, Megan E; Brunelle, Julie L; Green, Rachel

    2014-05-01

    Translation termination is promoted by class 1 and class 2 release factors in all domains of life. While the role of the bacterial class 1 factors, RF1 and RF2, in translation termination is well understood, the precise contribution of the bacterial class 2 release factor, RF3, to this process remains less clear. Here, we use a combination of binding assays and pre-steady state kinetics to provide a kinetic and thermodynamic framework for understanding the role of the translational GTPase RF3 in bacterial translation termination. First, we find that GDP and GTP have similar affinities for RF3 and that, on average, the t1/2 for nucleotide dissociation from the protein is 1-2 min. We further show that RF3:GDPNP, but not RF3:GDP, tightly associates with the ribosome pre- and post-termination complexes. Finally, we use stopped-flow fluorescence to demonstrate that RF3:GTP enhances RF1 dissociation rates by over 500-fold, providing the first direct observation of this step. Importantly, catalytically inactive variants of RF1 are not rapidly dissociated from the ribosome by RF3:GTP, arguing that a rotated state of the ribosome must be sampled for this step to efficiently occur. Together, these data define a more precise role for RF3 in translation termination and provide insights into the function of this family of translational GTPases.

  12. Classification of ulnar triangular fibrocartilage complex tears. A treatment algorithm for Palmer type IB tears.

    PubMed

    Atzei, A; Luchetti, R; Garagnani, L

    2017-01-01

    The classical definition of 'Palmer Type IB' triangular fibrocartilage complex tear, includes a spectrum of clinical conditions. This review highlights the clinical and arthroscopic criteria that enable us to categorize five classes on a treatment-oriented classification system of triangular fibrocartilage complex peripheral tears. Class 1 lesions represent isolated tears of the distal triangular fibrocartilage complex without distal radio-ulnar joint instability and are amenable to arthroscopic suture. Class 2 tears include rupture of both the distal triangular fibrocartilage complex and proximal attachments of the triangular fibrocartilage complex to the fovea. Class 3 tears constitute isolated ruptures of the proximal attachment of the triangular fibrocartilage complex to the fovea; they are not visible at radio-carpal arthroscopy. Both Class 2 and Class 3 tears are diagnosed with a positive hook test and are typically associated with distal radio-ulnar joint instability. If required, treatment is through reattachment of the distal radio-ulnar ligament insertions to the fovea. Class 4 lesions are irreparable tears due to the size of the defect or to poor tissue quality and, if required, treatment is through distal radio-ulnar ligament reconstruction with tendon graft. Class 5 tears are associated with distal radio-ulnar joint arthritis and can only be treated with salvage procedures. This subdivision of type IB triangular fibrocartilage complex tear provides more insights in the pathomechanics and treatment strategies.

  13. Profiling physical activity, diet, screen and sleep habits in Portuguese children.

    PubMed

    Pereira, Sara; Katzmarzyk, Peter T; Gomes, Thayse Natacha; Borges, Alessandra; Santos, Daniel; Souza, Michele; dos Santos, Fernanda K; Chaves, Raquel N; Champagne, Catherine M; Barreira, Tiago V; Maia, José A R

    2015-06-02

    Obesity in children is partly due to unhealthy lifestyle behaviours, e.g., sedentary activity and poor dietary choices. This trend has been seen globally. To determine the extent of these behaviours in a Portuguese population of children, 686 children 9.5 to 10.5 years of age were studied. Our aims were to: (1) describe profiles of children's lifestyle behaviours; (2) identify behaviour pattern classes; and (3) estimate combined effects of individual/ socio-demographic characteristics in predicting class membership. Physical activity and sleep time were estimated by 24-h accelerometry. Nutritional habits, screen time and socio-demographics were obtained. Latent Class Analysis was used to determine unhealthy lifestyle behaviours. Logistic regression analysis predicted class membership. About 78% of children had three or more unhealthy lifestyle behaviours, while 0.2% presented no risk. Two classes were identified: Class 1-Sedentary, poorer diet quality; and Class 2-Insufficiently active, better diet quality, 35% and 65% of the population, respectively. More mature children (Odds Ratio (OR) = 6.75; 95%CI = 4.74-10.41), and boys (OR = 3.06; 95% CI = 1.98-4.72) were more likely to be overweight/obese. However, those belonging to Class 2 were less likely to be overweight/obese (OR = 0.60; 95% CI = 0.43-0.84). Maternal education level and household income did not significantly predict weight status (p ≥ 0.05).

  14. A latent class regression analysis of men's conformity to masculine norms and psychological distress.

    PubMed

    Wong, Y Joel; Owen, Jesse; Shea, Munyi

    2012-01-01

    How are specific dimensions of masculinity related to psychological distress in specific groups of men? To address this question, the authors used latent class regression to assess the optimal number of latent classes that explained differential relationships between conformity to masculine norms and psychological distress in a racially diverse sample of 223 men. The authors identified a 2-class solution. Both latent classes demonstrated very different associations between conformity to masculine norms and psychological distress. In Class 1 (labeled risk avoiders; n = 133), conformity to the masculine norm of risk-taking was negatively related to psychological distress. In Class 2 (labeled detached risk-takers; n = 90), conformity to the masculine norms of playboy, self-reliance, and risk-taking was positively related to psychological distress, whereas conformity to the masculine norm of violence was negatively related to psychological distress. A post hoc analysis revealed that younger men and Asian American men (compared with Latino and White American men) had significantly greater odds of being in Class 2 versus Class 1. The implications of these findings for future research and clinical practice are examined.

  15. Risk factor profiles among intravenous drug using young adults: a latent class analysis (LCA) approach.

    PubMed

    James, Sigrid; McField, Edward S; Montgomery, Susanne B

    2013-03-01

    Using data from a cross-sectional study that examined health risk behaviors among urban intravenous drug-using (IDU) adolescents and young adults, this study investigated risk profiles among a high-risk sample (n=274). Risk profiles were empirically derived through latent class analysis based on indicators of engagement in health-risking behaviors, experience of abuse and violence as well as individual and family risk factors. The best fitting model was a 3-class model. Class 1 (n=95) captured participants with the lowest risk across all indicators. Compared to Class 1, Class 2 (n=128) and Class 3 (n=51) had elevated rates of engagement in health-risking behaviors as well as individual and family risk factors; however, Class 3 had the highest rate of engagement in sexual risk behavior, and backgrounds of substantial abuse and violence as well as familial psychopathology. Class 2 was the group most socioeconomically disadvantaged, with the highest percentage of participants coming from poor backgrounds, spending the longest time homeless and working the fewest months. Identifying subgroups of IDU has the potential to guide the development of more targeted and effective strategies for prevention and treatment of this high-risk population.

  16. Latent profile analyses of posttraumatic stress disorder, depression and generalized anxiety disorder symptoms in trauma-exposed soldiers.

    PubMed

    Contractor, Ateka A; Elhai, Jon D; Fine, Thomas H; Tamburrino, Marijo B; Cohen, Gregory; Shirley, Edwin; Chan, Philip K; Liberzon, Israel; Galea, Sandro; Calabrese, Joseph R

    2015-09-01

    Posttraumatic stress disorder (PTSD) is comorbid with major depressive disorder (MDD; Kessler et al., 1995) and generalized anxiety disorder (GAD; Brown et al., 2001). We aimed to (1) assess discrete patterns of post-trauma PTSD-depression-GAD symptoms using latent profile analyses (LPAs), and (2) assess covariates (gender, income, education, age) in defining the best fitting class solution. The PTSD Checklist (assessing PTSD symptoms), GAD-7 scale (assessing GAD symptoms), and Patient Health Questionnaire-9 (assessing depression) were administered to 1266 trauma-exposed Ohio National Guard soldiers. Results indicated three discrete subgroups based on symptom patterns with mild (class 1), moderate (class 2) and severe (class 3) levels of symptomatology. Classes differed in symptom severity rather than symptom type. Income and education significantly predicted class 1 versus class 3 membership, and class 2 versus class 3. In conclusion, there is heterogeneity regarding severity of PTSD-depression-GAD symptomatology among trauma-exposed soldiers, with income and education predictive of class membership.

  17. RBDMS user`s guide which includes the RBDMS administrative guide, Version 4.0. Appendix A

    SciTech Connect

    1995-03-01

    RBDMS (Risk Based Data Management System) is an oil and gas electronic data management system which stems from the idea developed from four previous projects conducted by the American Petroleum Institute (API) and the Ground Water Protection Council (GWPC). The first study studied oil and gas industry injection well corrosion. It included a methodology for assessing the probability of contaminating underground sources of drinking water (USDWs) via Class 2 injection well operations. A feasibility study was conducted to investigate if an electronic data management system could incorporate the methodology. A second feasibility study was conducted to test the methodology on a much small basis. The RBDMS effort then continued through a grant from DOE with a multi-task project consisting of an inventory and needs assessment of 25 oil and gas producing states pertaining to oil and gas production/regulatory activities, state geological/hydrogeological considerations, Class 2 underground injection activities, electronic data management needs and functional requirements, environmental risk assessment and management objectives, resultant benefit of a RBDMS, and various information and data required for the design and development of a RBDMS in individual states. This appendix contains the documentation for the use of the RBDMS.

  18. Quantification of ZP1, ZP2 and ZP3 mRNA of marmoset monkey (Callithrix jacchus) oocytes from periantral and antral follicles.

    PubMed

    Konrad, L; Kuhnert, S; Nayudu, P L; Einspanier, R; Hinsch, K D; Hinsch, E

    2012-05-01

    In mammals, the oocyte and preimplantation embryo are protected by the zona pellucida (ZP) consisting mainly of ZP glycoproteins, which are responsible for sperm binding, induction of the acrosome reaction and zona pellucida hardening to prevent polyspermia. The ZP proteins become increasingly important as possible predictors for in vitro cultured oocytes competence. As little is known about the stage-dependent expression of ZP1, ZP2 and ZP3 in marmoset monkey (Callithrix jacchus) oocytes, mRNA expression was investigated with real-time RT-PCR. Total-RNA was isolated from three different classes of marmoset oocytes; Class 1 oocytes from periantral follicles (<600 μm, n = 10), Class 2 oocytes from small antral follicles (600-1000 μm, n = 10) and Class 3 oocytes from large antral follicles (>1000 μm, n = 9). Compared with Class 1 oocytes mRNA expression of ZP1, ZP2 and ZP3 in Class 2 oocytes was significantly decreased. In Class 3 oocytes, the transcription of ZP1, ZP2 and ZP3 genes showed also a significant decrease compared with Class 1 oocytes. In this study a differently regulated expression of the ZP genes during late folliculogenesis with an obvious downregulation of ZP1, ZP2 and ZP3 could be demonstrated for the first time in the marmoset monkey.

  19. Retrieval study at 623 human mesh explants made of polypropylene--impact of mesh class and indication for mesh removal on tissue reaction.

    PubMed

    Klosterhalfen, B; Klinge, U

    2013-11-01

    Textile meshes frequently are implanted in the abdominal wall to reinforce a hernia repair. However, revisions for mesh associated complications confirm that these devices are not completely free of risk. Explanted devices offer an opportunity to define the impact of mesh structure on tissue response. This retrieval study analyses the tissue reaction to 623 polypropylene mesh samples (170 class 1 with large pores, and 453 class 2 with small pores) explanted for pain, infection, or recurrence. Histopathological assessment included morphometry of inflammatory infiltrate (IF) and connective tissue (CT), and of collagen 1/3 ratio. Half of the meshes were removed after more than 23 month. Despite large inter-individual differences removal for infection showed more IF than for pain or recurrence with significant correlation of IF with CT. Class 1 meshes with large pores showed less IF, CT, fistula formation, calcification, and bridging than class 2 meshes with small pores. Meshes removed for recurrence showed a lowered collagen 1/3 ratio in 70%. Large pore class 1 meshes showed an improved tissue response and may be considered as favorable to prevent inflammatory side effects. The presence of lowered collagen 1/3 ratio in most of the samples with recurrences stresses the relevance of an intact healing process. Late manifestation of complications demands long-lasting follow-up.

  20. Retrieval study at 623 human mesh explants made of polypropylene - impact of mesh class and indication for mesh removal on tissue reaction.

    PubMed

    Klosterhalfen, B; Klinge, U

    2013-05-19

    Textile meshes frequently are implanted in the abdominal wall to reinforce a hernia repair. However, revisions for mesh associated complications confirm that these devices are not completely free of risk. Explanted devices offer an opportunity to define the impact of mesh structure on tissue response. This retrieval study analyses the tissue reaction to 623 polypropylene mesh samples (170 class 1 with large pores, and 453 class 2 with small pores) explanted for pain, infection, or recurrence. Histopathological assessment included morphometry of inflammatory infiltrate (IF) and connective tissue (CT), and of collagen 1/3 ratio. Half of the meshes were removed after more than 23 month. Despite large inter-individual differences removal for infection showed more IF than for pain or recurrence with significant correlation of IF with CT. Class 1 meshes with large pores showed less IF, CT, fistula formation, calcification, and bridging than class 2 meshes with small pores. Meshes removed for recurrence showed a lowered collagen 1/3 ratio in 70%. Large pore class 1 meshes showed an improved tissue response and may be considered as favorable to prevent inflammatory side effects. The presence of lowered collagen 1/3 ratio in most of the samples with recurrences stresses the relevance of an intact healing process. Late manifestation of complications demands long-lasting follow-up. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.

  1. Organization of genes necessary for growth of the hydrogen methanol autotroph Xanthobacter sp. strain H4-14 on hydrogen and carbon dioxide

    SciTech Connect

    Lehmicke, L.G.; Lidstrom, M.E.

    1985-06-01

    Mutants unable to grow on H/sub 2/ and CO/sub 2/ were isolated in the hydrogen-methanol autotroph Xanthobacter sp. strain H4-14 and complemented with a clone bank constructed in a broad-host-range cosmid vector. The mutants fell into two classes. Class 1 mutants (Cfx/sup -/) cannot grow on hydrogen or methanol and are deficient in one or more of the key enzymes of the Calvin Cycle. Class 2 mutants (Hox/sup -/) can grow on methanol but not on hydrogen and lack hydrogenase activity. Restriction maps of the complementing clones show that each class is not linked to the other. Subcloning and Tn5 mutagenesis have localized the regions of DNA complementing these mutants. The region complementing a class 1 mutant which is deficient in ribulosebisphosphate carboxylase activity is approximately 3.2 kilobase pairs in size. Expression of this enzyme activity from cloned DNA gave evidence for the orientation of an operon containing the structural genes for this enzyme. The region complementing most of the class 2 mutants is 3 to 4.5 kilobase pairs in size.

  2. Crystal structure of human interferon-γ receptor 2 reveals the structural basis for receptor specificity

    PubMed Central

    Mikulecký, Pavel; Zahradník, Jirí; Kolenko, Petr; Černý, Jiří; Charnavets, Tatsiana; Kolářová, Lucie; Nečasová, Iva; Pham, Phuong Ngoc; Schneider, Bohdan

    2016-01-01

    Interferon-γ receptor 2 is a cell-surface receptor that is required for interferon-γ signalling and therefore plays a critical immunoregulatory role in innate and adaptive immunity against viral and also bacterial and protozoal infections. A crystal structure of the extracellular part of human interferon-γ receptor 2 (IFNγR2) was solved by molecular replacement at 1.8 Å resolution. Similar to other class 2 receptors, IFNγR2 has two fibronectin type III domains. The characteristic structural features of IFNγR2 are concentrated in its N-terminal domain: an extensive π–cation motif of stacked residues KWRWRH, a NAG–W–NAG sandwich (where NAG stands for N-acetyl-d-glucosamine) and finally a helix formed by residues 78–85, which is unique among class 2 receptors. Mass spectrometry and mutational analyses showed the importance of N-linked glycosylation to the stability of the protein and confirmed the presence of two disulfide bonds. Structure-based bioinformatic analysis revealed independent evolutionary behaviour of both receptor domains and, together with multiple sequence alignment, identified putative binding sites for interferon-γ and receptor 1, the ligands of IFNγR2. PMID:27599734

  3. Relationship between somatic mosaicism of Pax6 mutation and variable developmental eye abnormalities-an analysis of CRISPR genome-edited mouse embryos.

    PubMed

    Yasue, Akihiro; Kono, Hitomi; Habuta, Munenori; Bando, Tetsuya; Sato, Keita; Inoue, Junji; Oyadomari, Seiichi; Noji, Sumihare; Tanaka, Eiji; Ohuchi, Hideyo

    2017-12-01

    The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system is a rapid gene-targeting technology that does not require embryonic stem cells. To demonstrate dosage effects of the Pax6 gene on eye formation, we generated Pax6-deficient mice with the CRISPR/Cas system. Eyes of founder embryos at embryonic day (E) 16.5 were examined and categorized according to macroscopic phenotype as class 1 (small eye with distinct pigmentation), class 2 (pigmentation without eye globes), or class 3 (no pigmentation and no eyes). Histologically, class 1 eyes were abnormally small in size with lens still attached to the cornea at E16.5. Class 2 eyes had no lens and distorted convoluted retinas. Class 3 eyes had only rudimentary optic vesicle-like tissues or histological anophthalmia. Genotyping of neck tissue cells from the founder embryos revealed somatic mosaicism and allelic complexity for Pax6. Relationships between eye phenotype and genotype were developed. The present results demonstrated that development of the lens from the surface ectoderm requires a higher gene dose of Pax6 than development of the retina from the optic vesicle. We further anticipate that mice with somatic mosaicism in a targeted gene generated by CRISPR/Cas-mediated genome editing will give some insights for understanding the complexity in human congenital diseases that occur in mosaic form.

  4. Therapeutic drugs in early pregnancy and congenital defects.

    PubMed

    McDonald, A D

    1994-01-01

    In a study of occupation and pregnancy outcome, information was collected on certain non-occupational factors including therapeutic drugs taken in the first trimester, reported by some 17% of women. A case-referent analysis was made of data from pregnancies leading to 787 major (class 1) and 2386 miscellaneous minor (class 2) congenital defects compared with pregnancies without defects, matched for hospital, maternal age and educational level. In pairs discordant for one of seven drug groups, ratios of positive pairs (case with drug) to negative pairs (referent with drug) were for class 1 defects 164:148, relative risk (RR) 1.11 and for class 2 defects 433:383, RR 1.13. Only anti-infective drugs showed an increased RR: 1.70 (p = 0.06). This was mainly with nervous/sensory defects (10:2; RR 5.0, p = 0.04) but no one type of defect or type of drug was identified; the infections for which the drugs were given might have been responsible. For class 1 defects two pairs were positive for anti-convulsant drugs and two negative; no increase in risk was found for any specific drugs including doxylamine succinate (Bendectin).

  5. Evaluation of injection well risk management potential in the Williston Basin

    SciTech Connect

    1989-09-01

    The UIC regulations promulgated by the EPA under the Safe Drinking Water Act (SDWA) provide the EPA, or an EPA approved state agency, with authority to regulate subsurface injection of fluids to protect USDWs. Oil and gas producing industry interests are concerned primarily with Class 2 wells whose uses as defined by UIC regulations are: disposal of fluids brought to the surface and liquids generated in connection with oil and gas production (SWD); injection of fluids for enhanced oil recovery (EOR); and storage of liquid hydrocarbons. The Williston Basin was chosen for the pilot study of the feasibility of using the risk approach in managing Class 2 injection operations for the following reasons: it is one of the nine geologic basins which was classified as having a significant potential for external casing corrosion, which permitted an evaluation of the effectiveness of the injection well corrosion control measures used by industry; there are 731 active, 22 shut in and 203 temporarily abandoned SWD and water injection wells in the basin; and the basin covers three states. The broad objective of the Williston Basin study is to define requirements and to investigate the feasibility of incorporating risk management into administration of the UIC program. The study does not address the reporting aspects of UIC regulatory and compliance activities but the data base does contain essentially all the information required to develop the reports needed to monitor those activities. 16 refs., 10 figs., 11 tabs.

  6. Molecular characterization of multiresistant Escherichia coli producing or not extended-spectrum β-lactamases

    PubMed Central

    2013-01-01

    Background The prevalence and type of plasmids, resistance genes and integrons carried by two collections of multiresistant E. coli producing or not extended-spectrum β-lactamases have been compared. Rep-PCR was used to determine the clonal relationship of the organisms. Plasmids were classified according to their incompatibility. Class 1 and Class 2 integrons and antibiotic resistance genes were analysed by PCR and sequencing. Results Both collections of organisms contained a large diversity of unrelated strains with some clones distributed in both groups of isolates. Large plasmids were identified in the two groups of organisms. Plasmids with replicons repK and repColE were more frequent among ESBL-producing isolates, while repFIA, repFII and repA/C replicons were more frequent in isolates lacking ESBL. Conjugative plasmids with repK and repA/C replicons coded for CTX-M-14 and CMY-2 β-lactamases, respectively. No significant differences were observed in the distribution of class 1 and class 2 integrons among multiresistant E. coli producing or not ESBL, and dfrA17-ant(3″)-Ie was the cassette arrangement most commonly found. Conclusions In the concrete temporal and geographical context of this study, multiresistant E. coli producing ESBL or other mechanisms of resistance were largely clonally diverse and present some differences in the types of harboured plasmids. Still, some clones were found in both ESBL-producing and –lacking isolates. PMID:23586437

  7. Increased fitness of rice plants to abiotic stress via habitat adapted symbiosis: A strategy for mitigating impacts of climate change

    USGS Publications Warehouse

    Redman, R.S.; Kim, Y.-O.; Woodward, C.J.D.A.; Greer, C.; Espino, L.; Doty, S.L.; Rodriguez, R.J.

    2011-01-01

    Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing across moisture and salinity gradients. Plant growth and development, water usage, ROS sensitivity and osmolytes were measured with and without stress under controlled conditions. The endophytes conferred salt, drought and cold tolerance to growth chamber and greenhouse grown plants. Endophytes reduced water consumption by 20–30% and increased growth rate, reproductive yield, and biomass of greenhouse grown plants. In the absence of stress, there was no apparent cost of the endophytes to plants, however, endophyte colonization decreased from 100% at planting to 65% compared to greenhouse plants grown under continual stress (maintained 100% colonization). These findings indicate that rice plants can exhibit enhanced stress tolerance via symbiosis with Class 2 endophytes, and suggest that symbiotic technology may be useful in mitigating impacts of climate change on other crops and expanding agricultural production onto marginal lands.

  8. Comparison of oral health status between children with cerebral palsy and normal children in India: A case–control study

    PubMed Central

    Sinha, Nidhi; Singh, Bijay; Chhabra, Kumar Gaurav; Patil, Santosh

    2015-01-01

    Background: The aim of the present research was to describe and compare the oral health of children with cerebral palsy (CP) with the normal children in India. Materials and Methods: Fifty children with CP of the age range 7-17 years and fifty normal children were selected for the study. An oral examination was carried out and decayed, missing, and filled teeth (dmft/DMFT) index, oral hygiene index-simplified (OHI-S) index, Angles malocclusion were charted along with other significant dental findings. Data were analyzed using Student's t-test and Kruskal–Wallis one-way ANOVA test. Results: The mean dmft/DMFT of the CP group was 4.11 ± 2.62, while that of controls was 2.95 ± 2.75, which showed higher caries prevalence in the CP group. There was a significant association between the dmft/DMFT (P = 0.03), OHI-S (P = 0.001), and Angles Class 2 malocclusion and CP. Conclusions: Cerebral palsy group had higher caries, poor oral hygiene and Class 2 malocclusion when compared to controls primarily because of their compromised general health condition and also less dental awareness. Effort should be made for better organization of preventive dental care and promoting dental health of this challenged population. PMID:25810598

  9. Genetic diversity in clinical isolates of the dimorphic fungus Blastomyces dermatitidis detected by a PCR-based random amplified polymorphic DNA assay.

    PubMed

    Yates-Siilata, K E; Sander, D M; Keath, E J

    1995-08-01

    Blastomyces dermatitidis is a dimorphic fungus causing localized or systemic infection in areas where the organism is endemic in the central and southeastern United States. In this study, 19 independent isolates of B. dermatitidis from Little Rock, Ark., were grouped into three classes based on restriction fragment length polymorphism patterns in mitochondrial DNA with a heterologous probe from Histoplasma capsulatum. One large class of 15 isolates and two smaller classes (classes 2 and 3), each consisting of two isolates, were observed in BglII digests. Strain-specific arrays of PCR-amplified DNA products were obtained with arbitrarily selected primers (18 to 29 nucleotides long; G+C contents, 33 to 56%). In the large class 1 group, 13 isolates could be differentiated by the random amplified polymorphic DNA (RAPD) method with various primers. The two remaining class 1 isolates were obtained from the same patients and produced identical RAPD arrays. Dissimilar RAPD patterns were obtained from the smaller class 2 group but not from the class 3 isolates. Significant genetic diversity in clinical isolates of B. dermatitidis was observed; this may underscore a similar environmental diversification. Further application of the typing techniques may provide significant insight into the epidemiology of blastomycosis and aid in the assessment of specific virulence phenotypes.

  10. Reconnaissance amplitude versus offset techniques in the Niger Delta

    SciTech Connect

    Barton, J.; Gullette, K.

    1996-08-01

    Reconnaissance AVO (amplitude vs. offset) techniques have been invaluable in allowing the analyses and mapping of AVO on large-volume data sets in the Nigerian Niger Delta. Forward modelling of rock properties derived from well data on the shelf and regional ties of common depth point gathers to well control show that a shale on hydrocarbon bearing sand typically generates increasing amplitude with offset [Class 2 and Class 3 type anomalies of the Rutherford and Williams (1989) classification]. Consequently, processing and display techniques have been developed that distinguish the increasing amplitude with offset response associated with hydrocarbon bearing sands from the flatter AVO response of background water wet sands and shales. Attributes are created from angle stacks rather than by analyses of individual common depth point gathers over an entire data set. We show examples of a new AVO attribute which we call the Enhanced Restricted Gradient that highlights Class 2 and Class 3 type AVO anomalies more clearly than some of the standard AVO attributes used in the industry. The techniques described here provide a cost-effective and practical way of evaluating AVO character on large volume 2D and 3D data sets and should also be useful in other areas worldwide where hydrocarbon bearing reservoirs generate increasing amplitude with offset.

  11. Opportunities for Low Cost Titanium in Reduced Fuel Consumption, Improved Emissions, and Enhanced Durability Heavy Duty Vehicles

    SciTech Connect

    Kraft, E.H.

    2002-07-22

    The purpose of this study was to determine which components of heavy-duty highway vehicles are candidates for the substitution of titanium materials for current materials if the cost of those Ti components is very significantly reduced from current levels. The processes which could be used to produce those low cost components were also investigated. Heavy-duty highway vehicles are defined as all trucks and busses included in Classes 2C through 8. These include heavy pickups and vans above 8,500 lbs. GVWR, through highway tractor trailers. Class 8 is characterized as being a very cyclic market, with ''normal'' year volume, such as in 2000, of approximately 240,000 new vehicles. Classes 3-7 are less cyclic, with ''normal'' i.e., year 2000, volume totaling approximately 325,000 new vehicles. Classes 3-8 are powered about 88.5% by diesel engines, and Class 2C at very roughly 83% diesel. The engine portion of the study therefore focused on diesels. Vehicle production volumes were used in estimates of the market size for candidate components.

  12. Comparison of ubiquitous antibiotic-resistant Enterobacteriaceae populations isolated from wastewaters, surface waters and drinking waters.

    PubMed

    Figueira, Vânia; Serra, Elizabete A; Vaz-Moreira, Ivone; Brandão, Teresa R S; Manaia, Célia M

    2012-03-01

    This study aimed at assessing the role of ubiquitous (non-Escherichia coli) Enterobacteriaceae in the dissemination of antimicrobial resistance through the urban water cycle. Enterobacteriaceae isolated from a municipal wastewater treatment plant (111 isolates), urban water streams (33 isolates) and drinking water (123 isolates) were compared in terms of: (i) genera distribution, (ii) resistance to 12 antibiotics, and (iii) class 1 and class 2 integrons. The predominant bacterial genera were the same in the different types of water, although with a distinct pattern of species. The most prevalent resistance phenotypes were observed for amoxicillin, ticarcillin, cephalothin and sulphamethoxazole (24-59% in the three types of water). No resistance against ceftazidime or meropenem was observed. Resistance to cephalothin, amoxicillin and sulphamethoxazole was significantly more prevalent in drinking water, water streams and wastewater, respectively, than in the other types of water. It was possible to recognize antibiotic-resistance associations, namely for the pairs streptomycin-tetracycline (positive) and ticarcillin-cephalotin (negative). Class 1 and/or class 2 integrons with similar gene cassettes were detected in the three types of water. This study demonstrated that Enterobacteriaceae are important vehicles of antibiotic resistance, namely in drinking water.

  13. Trajectories of Television Watching from Childhood to Early Adulthood and Their Association with Body Composition and Mental Health Outcomes in Young Adults

    PubMed Central

    McVeigh, Joanne; Smith, Anne; Howie, Erin; Straker, Leon

    2016-01-01

    Introduction Prior studies examining longitudinal patterns of television (TV) watching have tended to use analytical approaches which do not allow for heterogeneity in the variation of TV watching over time. In the current study, we used latent class analysis (LCA) to examine the relationships between television watching (from childhood to early adulthood) and body fat percentage (%) and mental health. Methods Data were collected from 2411 participants (50% female) from the Raine Study, a prospective birth cohort study in Australia. Participants were followed up over 15 years and answered questions about hours of TV watching per week at six time-points (5, 8, 10, 14, 17 and 20yrs). Trajectories of television watching were estimated using LCA and appropriate regression models used to test the association of television watching class with percentage body fat (measured by DXA) and mental health (DASS-21) at age 20. Physical activity was used as a covariate. Results Three distinct trajectories of TV watching were identified. Class 1 (47.4%) had consistently high (>14 hrs/wk) levels of TV watching, Class 2 (37.9%) was characterised by an increase in TV watching over adolescence and Class 3 (14.7%) had consistently lower (<14 hrs/wk) TV watching over 15 years. Sex was used as an active covariate in the latent class model and was significantly associated with class membership (p<0.001), with females comprising 45%, 47% and 59% of Class 1, 2 and 3 respectively. In females, membership in Class 2 or 3 was associated with lower body fat % at age 20, compared to Class 1 (p<0.001). For males, membership in Class 2 was associated with lower body fat % compared with males in Class 1 (p = 0.026). Membership of TV watching class and mental health were not related (p>0.05). Conclusions TV watching from childhood to young adulthood appears to be a relatively stable behavior for around two thirds of participants, but not everyone tracks consistently. This study identified a subset of

  14. GaN Microwave DC-DC Converters

    NASA Astrophysics Data System (ADS)

    Ramos Franco, Ignacio

    Increasing the operating frequency of switching converters can have a direct impact in the miniaturization and integration of power converters. The size of energy-storage passive components and the difficulty to integrate them with the rest of the circuitry is a major challenge in the development of a fully integrated power supply on a chip. The work presented in this thesis attempts to address some of the difficulties encountered in the design of high-frequency converters by applying concepts and techniques usually used in the design of high-efficiency power amplifiers and high-efficiency rectifiers at microwave frequencies. The main focus is in the analysis, design, and characterization of dc-dc converters operating at microwave frequencies in the low gigahertz range. The concept of PA-rectifier duality, where a high-efficiency power amplifier operates as a high-efficiency rectifier is investigated through non-linear simulations and experimentally validated. Additionally, the concept of a self-synchronous rectifier, where a transistor rectifier operates synchronously without the need of a RF source or driver is demonstrated. A theoretical analysis of a class-E self-synchronous rectifier is presented and validated through non-linear simulations and experiments. Two GaN class-E2 dc-dc converters operating at a switching frequency of 1 and 1.2 GHz are demonstrated. The converters achieve 80 % and 75 % dc-dc efficiency respectively and are among the highest-frequency and highest-efficiency reported in the literature. The application of the concepts established in the analysis of a self-synchronous rectifier to a power amplifier culminated in the development of an oscillating, self-synchronous class-E 2 dc-dc converter. Finally, a proof-of-concept fully integrated GaN MMIC class-E 2 dc-dc converter switching at 4.6 GHz is demonstrated for the first time to the best of our knowledge. The 3.8 mm x 2.6 mm chip contains distributed inductors and does not require any external components. The maximum measured dc-dc efficiency is approximately 45%.

  15. Korean coastal water depth/sediment and land cover mapping (1:25,000) by computer analysis of LANDSAT imagery

    NASA Technical Reports Server (NTRS)

    Park, K. Y.; Miller, L. D.

    1978-01-01

    Computer analysis was applied to single date LANDSAT MSS imagery of a sample coastal area near Seoul, Korea equivalent to a 1:50,000 topographic map. Supervised image processing yielded a test classification map from this sample image containing 12 classes: 5 water depth/sediment classes, 2 shoreline/tidal classes, and 5 coastal land cover classes at a scale of 1:25,000 and with a training set accuracy of 76%. Unsupervised image classification was applied to a subportion of the site analyzed and produced classification maps comparable in results in a spatial sense. The results of this test indicated that it is feasible to produce such quantitative maps for detailed study of dynamic coastal processes given a LANDSAT image data base at sufficiently frequent time intervals.

  16. Instant and supersaturated dissolution of naproxen and sesamin (poorly water-soluble drugs and supplements) nanoparticles prepared by continuous expansion of liquid carbon dioxide solution through long dielectric nozzle

    NASA Astrophysics Data System (ADS)

    Arita, Toshihiko; Manabe, Noriyoshi; Nakahara, Koichi

    2012-11-01

    Nanoparticles (NPs) of naproxen (a nonsteroidal anti-inflammatory drug, BCS Class 2) and sesamin (a poorly water-soluble lignan) were investigated. By applying a newly developed rapid expansion system of liquid carbon dioxide solutions equipped with a dielectric nozzle, well-separated and fine both naproxen NPs (averaged particle size (APS) = 46.9 nm) and sesamin NPs (APS = 60.2 nm) were obtained without heating, surfactants, and co-solvents. Obtained naproxen and sesamin NPs had large surface/weight ratio, therefore, they showed instant dissolution to water until about ten percent higher than the saturated concentrations. In addition, the technique developed in the study has big advantage on producing especially drug NPs because the NPs produced by the method never includes neither poisonous additives (especially co-solvents and detergents) nor thermally denatured compounds.

  17. Materials Compatibility in High Test Hydrogen Peroxide

    NASA Technical Reports Server (NTRS)

    Gostowski, Rudy

    1999-01-01

    Previous ratings of the compatibility of high test hydrogen peroxide (HTP) with materials are not adequate for current needs. The goal of this work was to develop a new scheme of evaluation of compatibility of HTP with various materials. Procedures were developed to enrich commercially available hydrogen peroxide to 90% concentration and to assay the product. Reactivity testing, accelerated aging of materials and calorimetry studies were done on HTP with representative metallic and non-metallic materials. It was found that accelerated aging followed by concentration determination using refractive index effectively discriminated between different Class 2 metallic materials. Preliminary experiments using Differential Scanning Calorimetry (DSC) suggest that a calorimetry experiment is the most sensitive means to assay the compatibility of HTP with materials.

  18. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    SciTech Connect

    Raj Kumar; Keith Brown; T. Scott Hickman; James J. Justice

    2000-04-27

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents.

  19. Shock metamorphism of lunar and terrestrial basalts

    NASA Technical Reports Server (NTRS)

    Schaal, R. B.; Hoerz, F.

    1977-01-01

    Lonar Crater (India) basalt and lunar basalt 75035 were shock loaded under controlled laboratory conditions up to 1000 kbar, generally in a CO/CO2 (1:1) environment evacuated to 10 to the minus seventh power torr. The Kieffer et al. (1976) classification scheme of progressive shock metamorphism is found to apply to lunar basalts. The major shock features of the five classes that span the range 0 to 1000 kbar are described. Only three out of 152 basalt specimens show shock effects in their natural state as severe as Class 2 features. The scarcity of shocked basalt hand samples in contrast to the abundance of shock-produced agglutinates and homogeneous glass spheres in the lunar regolith indicates the dominant role of micrometeorite impact in the evolution of the lunar regolith. The overall glass content in asteroidal and Mercurian regoliths is considered.

  20. Origin of the Outer Solar System

    NASA Technical Reports Server (NTRS)

    Holman, Matthew J. (Principal Investigator); Boyce, Joseph (Technical Monitor)

    2003-01-01

    Our ongoing research program combines extensive deep and wide-field observations using a variety of observational platforms with numerical studies of the dynamics of small bodies in the outer solar system in order to advance the main scientific goals of the community studying the Kuiper belt and the outer solar system. These include: (1) determining the relative populations of the known classes of KBOs as well as other possible classes; (2) determining the size distributions or luminosity function of the individual populations or the Kuiper belt as a whole; (3) determining the inclinations distributions of these populations; (4) establishing the radial extent of the Kuiper belt; (5) measuring and relating the physical properties of different types of KBOs to those of other solar system bodies; and, (6) completing our systematic inventory of the satellites of the outer planets.